diff options
Diffstat (limited to 'kernel')
178 files changed, 16833 insertions, 7671 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 0b5ff083fa2..e9cf19155b4 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -21,7 +21,6 @@ CFLAGS_REMOVE_mutex-debug.o = -pg CFLAGS_REMOVE_rtmutex-debug.o = -pg CFLAGS_REMOVE_cgroup-debug.o = -pg CFLAGS_REMOVE_sched_clock.o = -pg -CFLAGS_REMOVE_perf_event.o = -pg CFLAGS_REMOVE_irq_work.o = -pg endif @@ -43,7 +42,7 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o -obj-$(CONFIG_USE_GENERIC_SMP_HELPERS) += smp.o +obj-$(CONFIG_SMP) += smp.o ifneq ($(CONFIG_SMP),y) obj-y += up.o endif @@ -100,12 +99,15 @@ obj-$(CONFIG_FUNCTION_TRACER) += trace/ obj-$(CONFIG_TRACING) += trace/ obj-$(CONFIG_X86_DS) += trace/ obj-$(CONFIG_RING_BUFFER) += trace/ +obj-$(CONFIG_TRACEPOINTS) += trace/ obj-$(CONFIG_SMP) += sched_cpupri.o obj-$(CONFIG_IRQ_WORK) += irq_work.o -obj-$(CONFIG_PERF_EVENTS) += perf_event.o -obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o + +obj-$(CONFIG_PERF_EVENTS) += events/ + obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o obj-$(CONFIG_PADATA) += padata.o +obj-$(CONFIG_CRASH_DUMP) += crash_dump.o ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is @@ -121,7 +123,7 @@ $(obj)/configs.o: $(obj)/config_data.h # config_data.h contains the same information as ikconfig.h but gzipped. # Info from config_data can be extracted from /proc/config* targets += config_data.gz -$(obj)/config_data.gz: .config FORCE +$(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(call if_changed,gzip) quiet_cmd_ikconfiggz = IKCFG $@ diff --git a/kernel/audit.c b/kernel/audit.c index 77770a034d5..93950031706 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -74,6 +74,8 @@ static int audit_initialized; int audit_enabled; int audit_ever_enabled; +EXPORT_SYMBOL_GPL(audit_enabled); + /* Default state when kernel boots without any parameters. */ static int audit_default; @@ -400,7 +402,7 @@ static void kauditd_send_skb(struct sk_buff *skb) if (err < 0) { BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */ printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid); - audit_log_lost("auditd dissapeared\n"); + audit_log_lost("auditd disappeared\n"); audit_pid = 0; /* we might get lucky and get this in the next auditd */ audit_hold_skb(skb); @@ -671,9 +673,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) pid = NETLINK_CREDS(skb)->pid; uid = NETLINK_CREDS(skb)->uid; - loginuid = NETLINK_CB(skb).loginuid; - sessionid = NETLINK_CB(skb).sessionid; - sid = NETLINK_CB(skb).sid; + loginuid = audit_get_loginuid(current); + sessionid = audit_get_sessionid(current); + security_task_getsecid(current, &sid); seq = nlh->nlmsg_seq; data = NLMSG_DATA(nlh); diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 37b2bea170c..e99dda04b12 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -607,7 +607,7 @@ void audit_trim_trees(void) spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) { struct audit_chunk *chunk = find_chunk(node); - /* this could be NULL if the watch is dieing else where... */ + /* this could be NULL if the watch is dying else where... */ struct inode *inode = chunk->mark.i.inode; node->index |= 1U<<31; if (iterate_mounts(compare_root, inode, root_mnt)) diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index d2e3c786646..e683869365d 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -144,9 +144,9 @@ int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev) } /* Initialize a parent watch entry. */ -static struct audit_parent *audit_init_parent(struct nameidata *ndp) +static struct audit_parent *audit_init_parent(struct path *path) { - struct inode *inode = ndp->path.dentry->d_inode; + struct inode *inode = path->dentry->d_inode; struct audit_parent *parent; int ret; @@ -353,53 +353,40 @@ static void audit_remove_parent_watches(struct audit_parent *parent) } /* Get path information necessary for adding watches. */ -static int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw) +static int audit_get_nd(struct audit_watch *watch, struct path *parent) { - struct nameidata *ndparent, *ndwatch; + struct nameidata nd; + struct dentry *d; int err; - ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); - if (unlikely(!ndparent)) - return -ENOMEM; + err = kern_path_parent(watch->path, &nd); + if (err) + return err; - ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); - if (unlikely(!ndwatch)) { - kfree(ndparent); - return -ENOMEM; + if (nd.last_type != LAST_NORM) { + path_put(&nd.path); + return -EINVAL; } - err = path_lookup(path, LOOKUP_PARENT, ndparent); - if (err) { - kfree(ndparent); - kfree(ndwatch); - return err; + mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); + d = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len); + if (IS_ERR(d)) { + mutex_unlock(&nd.path.dentry->d_inode->i_mutex); + path_put(&nd.path); + return PTR_ERR(d); } - - err = path_lookup(path, 0, ndwatch); - if (err) { - kfree(ndwatch); - ndwatch = NULL; + if (d->d_inode) { + /* update watch filter fields */ + watch->dev = d->d_inode->i_sb->s_dev; + watch->ino = d->d_inode->i_ino; } + mutex_unlock(&nd.path.dentry->d_inode->i_mutex); - *ndp = ndparent; - *ndw = ndwatch; - + *parent = nd.path; + dput(d); return 0; } -/* Release resources used for watch path information. */ -static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) -{ - if (ndp) { - path_put(&ndp->path); - kfree(ndp); - } - if (ndw) { - path_put(&ndw->path); - kfree(ndw); - } -} - /* Associate the given rule with an existing parent. * Caller must hold audit_filter_mutex. */ static void audit_add_to_parent(struct audit_krule *krule, @@ -440,31 +427,24 @@ int audit_add_watch(struct audit_krule *krule, struct list_head **list) { struct audit_watch *watch = krule->watch; struct audit_parent *parent; - struct nameidata *ndp = NULL, *ndw = NULL; + struct path parent_path; int h, ret = 0; mutex_unlock(&audit_filter_mutex); /* Avoid calling path_lookup under audit_filter_mutex. */ - ret = audit_get_nd(watch->path, &ndp, &ndw); - if (ret) { - /* caller expects mutex locked */ - mutex_lock(&audit_filter_mutex); - goto error; - } + ret = audit_get_nd(watch, &parent_path); + /* caller expects mutex locked */ mutex_lock(&audit_filter_mutex); - /* update watch filter fields */ - if (ndw) { - watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; - watch->ino = ndw->path.dentry->d_inode->i_ino; - } + if (ret) + return ret; /* either find an old parent or attach a new one */ - parent = audit_find_parent(ndp->path.dentry->d_inode); + parent = audit_find_parent(parent_path.dentry->d_inode); if (!parent) { - parent = audit_init_parent(ndp); + parent = audit_init_parent(&parent_path); if (IS_ERR(parent)) { ret = PTR_ERR(parent); goto error; @@ -479,9 +459,8 @@ int audit_add_watch(struct audit_krule *krule, struct list_head **list) h = audit_hash_ino((u32)watch->ino); *list = &audit_inode_hash[h]; error: - audit_put_nd(ndp, ndw); /* NULL args OK */ + path_put(&parent_path); return ret; - } void audit_remove_watch_rule(struct audit_krule *krule) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index add2819af71..f8277c80d67 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1238,6 +1238,7 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb, for (i = 0; i < rule->field_count; i++) { struct audit_field *f = &rule->fields[i]; int result = 0; + u32 sid; switch (f->type) { case AUDIT_PID: @@ -1250,19 +1251,22 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb, result = audit_comparator(cb->creds.gid, f->op, f->val); break; case AUDIT_LOGINUID: - result = audit_comparator(cb->loginuid, f->op, f->val); + result = audit_comparator(audit_get_loginuid(current), + f->op, f->val); break; case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: - if (f->lsm_rule) - result = security_audit_rule_match(cb->sid, + if (f->lsm_rule) { + security_task_getsecid(current, &sid); + result = security_audit_rule_match(sid, f->type, f->op, f->lsm_rule, NULL); + } break; } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index f49a0318c2e..b33513a08be 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1011,7 +1011,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid, /* * to_send and len_sent accounting are very loose estimates. We aren't * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being - * within about 500 bytes (next page boundry) + * within about 500 bytes (next page boundary) * * why snprintf? an int is up to 12 digits long. if we just assumed when * logging that a[%d]= was going to be 16 characters long we would be wasting diff --git a/kernel/bounds.c b/kernel/bounds.c index 98a51f26c13..0c9b862292b 100644 --- a/kernel/bounds.c +++ b/kernel/bounds.c @@ -9,11 +9,13 @@ #include <linux/page-flags.h> #include <linux/mmzone.h> #include <linux/kbuild.h> +#include <linux/page_cgroup.h> void foo(void) { /* The enum constants to put into include/generated/bounds.h */ DEFINE(NR_PAGEFLAGS, __NR_PAGEFLAGS); DEFINE(MAX_NR_ZONES, __MAX_NR_ZONES); + DEFINE(NR_PCG_FLAGS, __NR_PCG_FLAGS); /* End of constants */ } diff --git a/kernel/capability.c b/kernel/capability.c index 2f05303715a..32a80e08ff4 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -14,6 +14,7 @@ #include <linux/security.h> #include <linux/syscalls.h> #include <linux/pid_namespace.h> +#include <linux/user_namespace.h> #include <asm/uaccess.h> /* @@ -290,6 +291,60 @@ error: } /** + * has_capability - Does a task have a capability in init_user_ns + * @t: The task in question + * @cap: The capability to be tested for + * + * Return true if the specified task has the given superior capability + * currently in effect to the initial user namespace, false if not. + * + * Note that this does not set PF_SUPERPRIV on the task. + */ +bool has_capability(struct task_struct *t, int cap) +{ + int ret = security_real_capable(t, &init_user_ns, cap); + + return (ret == 0); +} + +/** + * has_capability - Does a task have a capability in a specific user ns + * @t: The task in question + * @ns: target user namespace + * @cap: The capability to be tested for + * + * Return true if the specified task has the given superior capability + * currently in effect to the specified user namespace, false if not. + * + * Note that this does not set PF_SUPERPRIV on the task. + */ +bool has_ns_capability(struct task_struct *t, + struct user_namespace *ns, int cap) +{ + int ret = security_real_capable(t, ns, cap); + + return (ret == 0); +} + +/** + * has_capability_noaudit - Does a task have a capability (unaudited) + * @t: The task in question + * @cap: The capability to be tested for + * + * Return true if the specified task has the given superior capability + * currently in effect to init_user_ns, false if not. Don't write an + * audit message for the check. + * + * Note that this does not set PF_SUPERPRIV on the task. + */ +bool has_capability_noaudit(struct task_struct *t, int cap) +{ + int ret = security_real_capable_noaudit(t, &init_user_ns, cap); + + return (ret == 0); +} + +/** * capable - Determine if the current task has a superior capability in effect * @cap: The capability to be tested for * @@ -299,17 +354,60 @@ error: * This sets PF_SUPERPRIV on the task if the capability is available on the * assumption that it's about to be used. */ -int capable(int cap) +bool capable(int cap) +{ + return ns_capable(&init_user_ns, cap); +} +EXPORT_SYMBOL(capable); + +/** + * ns_capable - Determine if the current task has a superior capability in effect + * @ns: The usernamespace we want the capability in + * @cap: The capability to be tested for + * + * Return true if the current task has the given superior capability currently + * available for use, false if not. + * + * This sets PF_SUPERPRIV on the task if the capability is available on the + * assumption that it's about to be used. + */ +bool ns_capable(struct user_namespace *ns, int cap) { if (unlikely(!cap_valid(cap))) { printk(KERN_CRIT "capable() called with invalid cap=%u\n", cap); BUG(); } - if (security_capable(cap) == 0) { + if (security_capable(ns, current_cred(), cap) == 0) { current->flags |= PF_SUPERPRIV; - return 1; + return true; } - return 0; + return false; +} +EXPORT_SYMBOL(ns_capable); + +/** + * task_ns_capable - Determine whether current task has a superior + * capability targeted at a specific task's user namespace. + * @t: The task whose user namespace is targeted. + * @cap: The capability in question. + * + * Return true if it does, false otherwise. + */ +bool task_ns_capable(struct task_struct *t, int cap) +{ + return ns_capable(task_cred_xxx(t, user)->user_ns, cap); +} +EXPORT_SYMBOL(task_ns_capable); + +/** + * nsown_capable - Check superior capability to one's own user_ns + * @cap: The capability in question + * + * Return true if the current task has the given superior capability + * targeted at its own user namespace. + */ +bool nsown_capable(int cap) +{ + return ns_capable(current_user_ns(), cap); } -EXPORT_SYMBOL(capable); diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 66a416b42c1..909a35510af 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -157,7 +157,7 @@ struct css_id { }; /* - * cgroup_event represents events which userspace want to recieve. + * cgroup_event represents events which userspace want to receive. */ struct cgroup_event { /* @@ -326,12 +326,6 @@ static struct hlist_head *css_set_hash(struct cgroup_subsys_state *css[]) return &css_set_table[index]; } -static void free_css_set_rcu(struct rcu_head *obj) -{ - struct css_set *cg = container_of(obj, struct css_set, rcu_head); - kfree(cg); -} - /* We don't maintain the lists running through each css_set to its * task until after the first call to cgroup_iter_start(). This * reduces the fork()/exit() overhead for people who have cgroups @@ -375,7 +369,7 @@ static void __put_css_set(struct css_set *cg, int taskexit) } write_unlock(&css_set_lock); - call_rcu(&cg->rcu_head, free_css_set_rcu); + kfree_rcu(cg, rcu_head); } /* @@ -764,6 +758,7 @@ EXPORT_SYMBOL_GPL(cgroup_unlock); */ static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode); +static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *); static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry); static int cgroup_populate_dir(struct cgroup *cgrp); static const struct inode_operations cgroup_dir_inode_operations; @@ -811,13 +806,6 @@ static int cgroup_call_pre_destroy(struct cgroup *cgrp) return ret; } -static void free_cgroup_rcu(struct rcu_head *obj) -{ - struct cgroup *cgrp = container_of(obj, struct cgroup, rcu_head); - - kfree(cgrp); -} - static void cgroup_diput(struct dentry *dentry, struct inode *inode) { /* is dentry a directory ? if so, kfree() associated cgroup */ @@ -855,11 +843,16 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) */ BUG_ON(!list_empty(&cgrp->pidlists)); - call_rcu(&cgrp->rcu_head, free_cgroup_rcu); + kfree_rcu(cgrp, rcu_head); } iput(inode); } +static int cgroup_delete(const struct dentry *d) +{ + return 1; +} + static void remove_dir(struct dentry *d) { struct dentry *parent = dget(d->d_parent); @@ -874,25 +867,29 @@ static void cgroup_clear_directory(struct dentry *dentry) struct list_head *node; BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex)); - spin_lock(&dcache_lock); + spin_lock(&dentry->d_lock); node = dentry->d_subdirs.next; while (node != &dentry->d_subdirs) { struct dentry *d = list_entry(node, struct dentry, d_u.d_child); + + spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); list_del_init(node); if (d->d_inode) { /* This should never be called on a cgroup * directory with child cgroups */ BUG_ON(d->d_inode->i_mode & S_IFDIR); - d = dget_locked(d); - spin_unlock(&dcache_lock); + dget_dlock(d); + spin_unlock(&d->d_lock); + spin_unlock(&dentry->d_lock); d_delete(d); simple_unlink(dentry->d_inode, d); dput(d); - spin_lock(&dcache_lock); - } + spin_lock(&dentry->d_lock); + } else + spin_unlock(&d->d_lock); node = dentry->d_subdirs.next; } - spin_unlock(&dcache_lock); + spin_unlock(&dentry->d_lock); } /* @@ -900,11 +897,16 @@ static void cgroup_clear_directory(struct dentry *dentry) */ static void cgroup_d_remove_dir(struct dentry *dentry) { + struct dentry *parent; + cgroup_clear_directory(dentry); - spin_lock(&dcache_lock); + parent = dentry->d_parent; + spin_lock(&parent->d_lock); + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); list_del_init(&dentry->d_u.d_child); - spin_unlock(&dcache_lock); + spin_unlock(&dentry->d_lock); + spin_unlock(&parent->d_lock); remove_dir(dentry); } @@ -1440,6 +1442,11 @@ static int cgroup_set_super(struct super_block *sb, void *data) static int cgroup_get_rootdir(struct super_block *sb) { + static const struct dentry_operations cgroup_dops = { + .d_iput = cgroup_diput, + .d_delete = cgroup_delete, + }; + struct inode *inode = cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb); struct dentry *dentry; @@ -1457,6 +1464,8 @@ static int cgroup_get_rootdir(struct super_block *sb) return -ENOMEM; } sb->s_root = dentry; + /* for everything else we want ->d_op set */ + sb->s_d_op = &cgroup_dops; return 0; } @@ -1791,10 +1800,8 @@ int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk) /* Update the css_set linked lists if we're using them */ write_lock(&css_set_lock); - if (!list_empty(&tsk->cg_list)) { - list_del(&tsk->cg_list); - list_add(&tsk->cg_list, &newcg->tasks); - } + if (!list_empty(&tsk->cg_list)) + list_move(&tsk->cg_list, &newcg->tasks); write_unlock(&css_set_lock); for_each_subsys(root, ss) { @@ -2180,12 +2187,20 @@ static const struct file_operations cgroup_file_operations = { }; static const struct inode_operations cgroup_dir_inode_operations = { - .lookup = simple_lookup, + .lookup = cgroup_lookup, .mkdir = cgroup_mkdir, .rmdir = cgroup_rmdir, .rename = cgroup_rename, }; +static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) +{ + if (dentry->d_name.len > NAME_MAX) + return ERR_PTR(-ENAMETOOLONG); + d_add(dentry, NULL); + return NULL; +} + /* * Check if a file is a control file */ @@ -2199,10 +2214,6 @@ static inline struct cftype *__file_cft(struct file *file) static int cgroup_create_file(struct dentry *dentry, mode_t mode, struct super_block *sb) { - static const struct dentry_operations cgroup_dops = { - .d_iput = cgroup_diput, - }; - struct inode *inode; if (!dentry) @@ -2228,7 +2239,6 @@ static int cgroup_create_file(struct dentry *dentry, mode_t mode, inode->i_size = 0; inode->i_fop = &cgroup_file_operations; } - dentry->d_op = &cgroup_dops; d_instantiate(dentry, inode); dget(dentry); /* Extra count - pin the dentry in core */ return 0; @@ -3630,17 +3640,15 @@ again: spin_lock(&release_list_lock); set_bit(CGRP_REMOVED, &cgrp->flags); if (!list_empty(&cgrp->release_list)) - list_del(&cgrp->release_list); + list_del_init(&cgrp->release_list); spin_unlock(&release_list_lock); cgroup_lock_hierarchy(cgrp->root); /* delete this cgroup from parent->children */ - list_del(&cgrp->sibling); + list_del_init(&cgrp->sibling); cgroup_unlock_hierarchy(cgrp->root); - spin_lock(&cgrp->dentry->d_lock); d = dget(cgrp->dentry); - spin_unlock(&d->d_lock); cgroup_d_remove_dir(d); dput(d); @@ -3856,7 +3864,7 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) subsys[ss->subsys_id] = NULL; /* remove subsystem from rootnode's list of subsystems */ - list_del(&ss->sibling); + list_del_init(&ss->sibling); /* * disentangle the css from all css_sets attached to the dummytop. as @@ -4207,20 +4215,8 @@ void cgroup_post_fork(struct task_struct *child) */ void cgroup_exit(struct task_struct *tsk, int run_callbacks) { - int i; struct css_set *cg; - - if (run_callbacks && need_forkexit_callback) { - /* - * modular subsystems can't use callbacks, so no need to lock - * the subsys array - */ - for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) { - struct cgroup_subsys *ss = subsys[i]; - if (ss->exit) - ss->exit(ss, tsk); - } - } + int i; /* * Unlink from the css_set task list if necessary. @@ -4230,7 +4226,7 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks) if (!list_empty(&tsk->cg_list)) { write_lock(&css_set_lock); if (!list_empty(&tsk->cg_list)) - list_del(&tsk->cg_list); + list_del_init(&tsk->cg_list); write_unlock(&css_set_lock); } @@ -4238,7 +4234,24 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks) task_lock(tsk); cg = tsk->cgroups; tsk->cgroups = &init_css_set; + + if (run_callbacks && need_forkexit_callback) { + /* + * modular subsystems can't use callbacks, so no need to lock + * the subsys array + */ + for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) { + struct cgroup_subsys *ss = subsys[i]; + if (ss->exit) { + struct cgroup *old_cgrp = + rcu_dereference_raw(cg->subsys[i])->cgroup; + struct cgroup *cgrp = task_cgroup(tsk, i); + ss->exit(ss, cgrp, old_cgrp, tsk); + } + } + } task_unlock(tsk); + if (cg) put_css_set_taskexit(cg); } @@ -4597,14 +4610,6 @@ bool css_is_ancestor(struct cgroup_subsys_state *child, return ret; } -static void __free_css_id_cb(struct rcu_head *head) -{ - struct css_id *id; - - id = container_of(head, struct css_id, rcu_head); - kfree(id); -} - void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css) { struct css_id *id = css->id; @@ -4619,7 +4624,7 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css) spin_lock(&ss->id_lock); idr_remove(&ss->idr, id->id); spin_unlock(&ss->id_lock); - call_rcu(&id->rcu_head, __free_css_id_cb); + kfree_rcu(id, rcu_head); } EXPORT_SYMBOL_GPL(free_css_id); @@ -4790,6 +4795,29 @@ css_get_next(struct cgroup_subsys *ss, int id, return ret; } +/* + * get corresponding css from file open on cgroupfs directory + */ +struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id) +{ + struct cgroup *cgrp; + struct inode *inode; + struct cgroup_subsys_state *css; + + inode = f->f_dentry->d_inode; + /* check in cgroup filesystem dir */ + if (inode->i_op != &cgroup_dir_inode_operations) + return ERR_PTR(-EBADF); + + if (id < 0 || id >= CGROUP_SUBSYS_COUNT) + return ERR_PTR(-EINVAL); + + /* get cgroup */ + cgrp = __d_cgrp(f->f_dentry); + css = cgrp->subsys[id]; + return css ? css : ERR_PTR(-ENOENT); +} + #ifdef CONFIG_CGROUP_DEBUG static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss, struct cgroup *cont) diff --git a/kernel/compat.c b/kernel/compat.c index c9e2ec0b34a..38b1d2c1cbe 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -52,6 +52,64 @@ static int compat_put_timeval(struct compat_timeval __user *o, put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0; } +static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp) +{ + memset(txc, 0, sizeof(struct timex)); + + if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) || + __get_user(txc->modes, &utp->modes) || + __get_user(txc->offset, &utp->offset) || + __get_user(txc->freq, &utp->freq) || + __get_user(txc->maxerror, &utp->maxerror) || + __get_user(txc->esterror, &utp->esterror) || + __get_user(txc->status, &utp->status) || + __get_user(txc->constant, &utp->constant) || + __get_user(txc->precision, &utp->precision) || + __get_user(txc->tolerance, &utp->tolerance) || + __get_user(txc->time.tv_sec, &utp->time.tv_sec) || + __get_user(txc->time.tv_usec, &utp->time.tv_usec) || + __get_user(txc->tick, &utp->tick) || + __get_user(txc->ppsfreq, &utp->ppsfreq) || + __get_user(txc->jitter, &utp->jitter) || + __get_user(txc->shift, &utp->shift) || + __get_user(txc->stabil, &utp->stabil) || + __get_user(txc->jitcnt, &utp->jitcnt) || + __get_user(txc->calcnt, &utp->calcnt) || + __get_user(txc->errcnt, &utp->errcnt) || + __get_user(txc->stbcnt, &utp->stbcnt)) + return -EFAULT; + + return 0; +} + +static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc) +{ + if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) || + __put_user(txc->modes, &utp->modes) || + __put_user(txc->offset, &utp->offset) || + __put_user(txc->freq, &utp->freq) || + __put_user(txc->maxerror, &utp->maxerror) || + __put_user(txc->esterror, &utp->esterror) || + __put_user(txc->status, &utp->status) || + __put_user(txc->constant, &utp->constant) || + __put_user(txc->precision, &utp->precision) || + __put_user(txc->tolerance, &utp->tolerance) || + __put_user(txc->time.tv_sec, &utp->time.tv_sec) || + __put_user(txc->time.tv_usec, &utp->time.tv_usec) || + __put_user(txc->tick, &utp->tick) || + __put_user(txc->ppsfreq, &utp->ppsfreq) || + __put_user(txc->jitter, &utp->jitter) || + __put_user(txc->shift, &utp->shift) || + __put_user(txc->stabil, &utp->stabil) || + __put_user(txc->jitcnt, &utp->jitcnt) || + __put_user(txc->calcnt, &utp->calcnt) || + __put_user(txc->errcnt, &utp->errcnt) || + __put_user(txc->stbcnt, &utp->stbcnt) || + __put_user(txc->tai, &utp->tai)) + return -EFAULT; + return 0; +} + asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv, struct timezone __user *tz) { @@ -617,6 +675,29 @@ long compat_sys_clock_gettime(clockid_t which_clock, return err; } +long compat_sys_clock_adjtime(clockid_t which_clock, + struct compat_timex __user *utp) +{ + struct timex txc; + mm_segment_t oldfs; + int err, ret; + + err = compat_get_timex(&txc, utp); + if (err) + return err; + + oldfs = get_fs(); + set_fs(KERNEL_DS); + ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc); + set_fs(oldfs); + + err = compat_put_timex(utp, &txc); + if (err) + return err; + + return ret; +} + long compat_sys_clock_getres(clockid_t which_clock, struct compat_timespec __user *tp) { @@ -951,58 +1032,17 @@ asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp) { struct timex txc; - int ret; - - memset(&txc, 0, sizeof(struct timex)); + int err, ret; - if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) || - __get_user(txc.modes, &utp->modes) || - __get_user(txc.offset, &utp->offset) || - __get_user(txc.freq, &utp->freq) || - __get_user(txc.maxerror, &utp->maxerror) || - __get_user(txc.esterror, &utp->esterror) || - __get_user(txc.status, &utp->status) || - __get_user(txc.constant, &utp->constant) || - __get_user(txc.precision, &utp->precision) || - __get_user(txc.tolerance, &utp->tolerance) || - __get_user(txc.time.tv_sec, &utp->time.tv_sec) || - __get_user(txc.time.tv_usec, &utp->time.tv_usec) || - __get_user(txc.tick, &utp->tick) || - __get_user(txc.ppsfreq, &utp->ppsfreq) || - __get_user(txc.jitter, &utp->jitter) || - __get_user(txc.shift, &utp->shift) || - __get_user(txc.stabil, &utp->stabil) || - __get_user(txc.jitcnt, &utp->jitcnt) || - __get_user(txc.calcnt, &utp->calcnt) || - __get_user(txc.errcnt, &utp->errcnt) || - __get_user(txc.stbcnt, &utp->stbcnt)) - return -EFAULT; + err = compat_get_timex(&txc, utp); + if (err) + return err; ret = do_adjtimex(&txc); - if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) || - __put_user(txc.modes, &utp->modes) || - __put_user(txc.offset, &utp->offset) || - __put_user(txc.freq, &utp->freq) || - __put_user(txc.maxerror, &utp->maxerror) || - __put_user(txc.esterror, &utp->esterror) || - __put_user(txc.status, &utp->status) || - __put_user(txc.constant, &utp->constant) || - __put_user(txc.precision, &utp->precision) || - __put_user(txc.tolerance, &utp->tolerance) || - __put_user(txc.time.tv_sec, &utp->time.tv_sec) || - __put_user(txc.time.tv_usec, &utp->time.tv_usec) || - __put_user(txc.tick, &utp->tick) || - __put_user(txc.ppsfreq, &utp->ppsfreq) || - __put_user(txc.jitter, &utp->jitter) || - __put_user(txc.shift, &utp->shift) || - __put_user(txc.stabil, &utp->stabil) || - __put_user(txc.jitcnt, &utp->jitcnt) || - __put_user(txc.calcnt, &utp->calcnt) || - __put_user(txc.errcnt, &utp->errcnt) || - __put_user(txc.stbcnt, &utp->stbcnt) || - __put_user(txc.tai, &utp->tai)) - ret = -EFAULT; + err = compat_put_timex(utp, &txc); + if (err) + return err; return ret; } diff --git a/kernel/cpu.c b/kernel/cpu.c index f6e726f1849..12b7458f23b 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -126,7 +126,7 @@ static void cpu_hotplug_done(void) #else /* #if CONFIG_HOTPLUG_CPU */ static void cpu_hotplug_begin(void) {} static void cpu_hotplug_done(void) {} -#endif /* #esle #if CONFIG_HOTPLUG_CPU */ +#endif /* #else #if CONFIG_HOTPLUG_CPU */ /* Need to know about CPUs going up/down? */ int __ref register_cpu_notifier(struct notifier_block *nb) @@ -160,7 +160,6 @@ static void cpu_notify_nofail(unsigned long val, void *v) { BUG_ON(cpu_notify(val, v)); } - EXPORT_SYMBOL(register_cpu_notifier); void __ref unregister_cpu_notifier(struct notifier_block *nb) @@ -189,7 +188,6 @@ static inline void check_for_tasks(int cpu) } struct take_cpu_down_param { - struct task_struct *caller; unsigned long mod; void *hcpu; }; @@ -198,7 +196,6 @@ struct take_cpu_down_param { static int __ref take_cpu_down(void *_param) { struct take_cpu_down_param *param = _param; - unsigned int cpu = (unsigned long)param->hcpu; int err; /* Ensure this CPU doesn't handle any more interrupts. */ @@ -207,12 +204,6 @@ static int __ref take_cpu_down(void *_param) return err; cpu_notify(CPU_DYING | param->mod, param->hcpu); - - if (task_cpu(param->caller) == cpu) - move_task_off_dead_cpu(cpu, param->caller); - /* Force idle task to run as soon as we yield: it should - immediately notice cpu is offline and die quickly. */ - sched_idle_next(); return 0; } @@ -223,7 +214,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; struct take_cpu_down_param tcd_param = { - .caller = current, .mod = mod, .hcpu = hcpu, }; @@ -235,6 +225,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) return -EINVAL; cpu_hotplug_begin(); + err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); if (err) { nr_calls--; @@ -253,9 +244,15 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) } BUG_ON(cpu_online(cpu)); - /* Wait for it to sleep (leaving idle task). */ + /* + * The migration_call() CPU_DYING callback will have removed all + * runnable tasks from the cpu, there's only the idle task left now + * that the migration thread is done doing the stop_machine thing. + * + * Wait for the stop thread to go away. + */ while (!idle_cpu(cpu)) - yield(); + cpu_relax(); /* This actually kills the CPU. */ __cpu_die(cpu); @@ -306,7 +303,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); if (ret) { nr_calls--; - printk("%s: attempt to bring up CPU %u failed\n", + printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n", __func__, cpu); goto out_notify; } @@ -386,6 +383,14 @@ out: #ifdef CONFIG_PM_SLEEP_SMP static cpumask_var_t frozen_cpus; +void __weak arch_disable_nonboot_cpus_begin(void) +{ +} + +void __weak arch_disable_nonboot_cpus_end(void) +{ +} + int disable_nonboot_cpus(void) { int cpu, first_cpu, error = 0; @@ -397,6 +402,7 @@ int disable_nonboot_cpus(void) * with the userspace trying to use the CPU hotplug at the same time */ cpumask_clear(frozen_cpus); + arch_disable_nonboot_cpus_begin(); printk("Disabling non-boot CPUs ...\n"); for_each_online_cpu(cpu) { @@ -412,6 +418,8 @@ int disable_nonboot_cpus(void) } } + arch_disable_nonboot_cpus_end(); + if (!error) { BUG_ON(num_online_cpus() > 1); /* Make sure the CPUs won't be enabled by someone else */ @@ -441,14 +449,14 @@ void __ref enable_nonboot_cpus(void) if (cpumask_empty(frozen_cpus)) goto out; - printk("Enabling non-boot CPUs ...\n"); + printk(KERN_INFO "Enabling non-boot CPUs ...\n"); arch_enable_nonboot_cpus_begin(); for_each_cpu(cpu, frozen_cpus) { error = _cpu_up(cpu, 1); if (!error) { - printk("CPU%d is up\n", cpu); + printk(KERN_INFO "CPU%d is up\n", cpu); continue; } printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error); @@ -500,7 +508,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu) */ /* cpu_bit_bitmap[0] is empty - so we can back into it */ -#define MASK_DECLARE_1(x) [x+1][0] = 1UL << (x) +#define MASK_DECLARE_1(x) [x+1][0] = (1UL << (x)) #define MASK_DECLARE_2(x) MASK_DECLARE_1(x), MASK_DECLARE_1(x+1) #define MASK_DECLARE_4(x) MASK_DECLARE_2(x), MASK_DECLARE_2(x+2) #define MASK_DECLARE_8(x) MASK_DECLARE_4(x), MASK_DECLARE_4(x+4) diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 4349935c2ad..2bb8c2e98ff 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1015,17 +1015,12 @@ static void cpuset_change_nodemask(struct task_struct *p, struct cpuset *cs; int migrate; const nodemask_t *oldmem = scan->data; - NODEMASK_ALLOC(nodemask_t, newmems, GFP_KERNEL); - - if (!newmems) - return; + static nodemask_t newmems; /* protected by cgroup_mutex */ cs = cgroup_cs(scan->cg); - guarantee_online_mems(cs, newmems); - - cpuset_change_task_nodemask(p, newmems); + guarantee_online_mems(cs, &newmems); - NODEMASK_FREE(newmems); + cpuset_change_task_nodemask(p, &newmems); mm = get_task_mm(p); if (!mm) @@ -1164,7 +1159,7 @@ int current_cpuset_is_being_rebound(void) static int update_relax_domain_level(struct cpuset *cs, s64 val) { #ifdef CONFIG_SMP - if (val < -1 || val >= SD_LV_MAX) + if (val < -1 || val >= sched_domain_level_max) return -EINVAL; #endif @@ -1438,44 +1433,35 @@ static void cpuset_attach(struct cgroup_subsys *ss, struct cgroup *cont, struct mm_struct *mm; struct cpuset *cs = cgroup_cs(cont); struct cpuset *oldcs = cgroup_cs(oldcont); - NODEMASK_ALLOC(nodemask_t, from, GFP_KERNEL); - NODEMASK_ALLOC(nodemask_t, to, GFP_KERNEL); - - if (from == NULL || to == NULL) - goto alloc_fail; + static nodemask_t to; /* protected by cgroup_mutex */ if (cs == &top_cpuset) { cpumask_copy(cpus_attach, cpu_possible_mask); } else { guarantee_online_cpus(cs, cpus_attach); } - guarantee_online_mems(cs, to); + guarantee_online_mems(cs, &to); /* do per-task migration stuff possibly for each in the threadgroup */ - cpuset_attach_task(tsk, to, cs); + cpuset_attach_task(tsk, &to, cs); if (threadgroup) { struct task_struct *c; rcu_read_lock(); list_for_each_entry_rcu(c, &tsk->thread_group, thread_group) { - cpuset_attach_task(c, to, cs); + cpuset_attach_task(c, &to, cs); } rcu_read_unlock(); } /* change mm; only needs to be done once even if threadgroup */ - *from = oldcs->mems_allowed; - *to = cs->mems_allowed; + to = cs->mems_allowed; mm = get_task_mm(tsk); if (mm) { - mpol_rebind_mm(mm, to); + mpol_rebind_mm(mm, &to); if (is_memory_migrate(cs)) - cpuset_migrate_mm(mm, from, to); + cpuset_migrate_mm(mm, &oldcs->mems_allowed, &to); mmput(mm); } - -alloc_fail: - NODEMASK_FREE(from); - NODEMASK_FREE(to); } /* The various types of files and directories in a cpuset file system */ @@ -1575,8 +1561,10 @@ static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, return -ENODEV; trialcs = alloc_trial_cpuset(cs); - if (!trialcs) - return -ENOMEM; + if (!trialcs) { + retval = -ENOMEM; + goto out; + } switch (cft->private) { case FILE_CPULIST: @@ -1591,6 +1579,7 @@ static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, } free_trial_cpuset(trialcs); +out: cgroup_unlock(); return retval; } @@ -1607,34 +1596,26 @@ static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, * across a page fault. */ -static int cpuset_sprintf_cpulist(char *page, struct cpuset *cs) +static size_t cpuset_sprintf_cpulist(char *page, struct cpuset *cs) { - int ret; + size_t count; mutex_lock(&callback_mutex); - ret = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); + count = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); mutex_unlock(&callback_mutex); - return ret; + return count; } -static int cpuset_sprintf_memlist(char *page, struct cpuset *cs) +static size_t cpuset_sprintf_memlist(char *page, struct cpuset *cs) { - NODEMASK_ALLOC(nodemask_t, mask, GFP_KERNEL); - int retval; - - if (mask == NULL) - return -ENOMEM; + size_t count; mutex_lock(&callback_mutex); - *mask = cs->mems_allowed; + count = nodelist_scnprintf(page, PAGE_SIZE, cs->mems_allowed); mutex_unlock(&callback_mutex); - retval = nodelist_scnprintf(page, PAGE_SIZE, *mask); - - NODEMASK_FREE(mask); - - return retval; + return count; } static ssize_t cpuset_common_file_read(struct cgroup *cont, @@ -1859,8 +1840,10 @@ static void cpuset_post_clone(struct cgroup_subsys *ss, cs = cgroup_cs(cgroup); parent_cs = cgroup_cs(parent); + mutex_lock(&callback_mutex); cs->mems_allowed = parent_cs->mems_allowed; cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed); + mutex_unlock(&callback_mutex); return; } @@ -2063,10 +2046,7 @@ static void scan_for_empty_cpusets(struct cpuset *root) struct cpuset *cp; /* scans cpusets being updated */ struct cpuset *child; /* scans child cpusets of cp */ struct cgroup *cont; - NODEMASK_ALLOC(nodemask_t, oldmems, GFP_KERNEL); - - if (oldmems == NULL) - return; + static nodemask_t oldmems; /* protected by cgroup_mutex */ list_add_tail((struct list_head *)&root->stack_list, &queue); @@ -2083,7 +2063,7 @@ static void scan_for_empty_cpusets(struct cpuset *root) nodes_subset(cp->mems_allowed, node_states[N_HIGH_MEMORY])) continue; - *oldmems = cp->mems_allowed; + oldmems = cp->mems_allowed; /* Remove offline cpus and mems from this cpuset. */ mutex_lock(&callback_mutex); @@ -2099,10 +2079,9 @@ static void scan_for_empty_cpusets(struct cpuset *root) remove_tasks_in_empty_cpuset(cp); else { update_tasks_cpumask(cp, NULL); - update_tasks_nodemask(cp, oldmems, NULL); + update_tasks_nodemask(cp, &oldmems, NULL); } } - NODEMASK_FREE(oldmems); } /* @@ -2144,19 +2123,16 @@ void cpuset_update_active_cpus(void) static int cpuset_track_online_nodes(struct notifier_block *self, unsigned long action, void *arg) { - NODEMASK_ALLOC(nodemask_t, oldmems, GFP_KERNEL); - - if (oldmems == NULL) - return NOTIFY_DONE; + static nodemask_t oldmems; /* protected by cgroup_mutex */ cgroup_lock(); switch (action) { case MEM_ONLINE: - *oldmems = top_cpuset.mems_allowed; + oldmems = top_cpuset.mems_allowed; mutex_lock(&callback_mutex); top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; mutex_unlock(&callback_mutex); - update_tasks_nodemask(&top_cpuset, oldmems, NULL); + update_tasks_nodemask(&top_cpuset, &oldmems, NULL); break; case MEM_OFFLINE: /* @@ -2170,7 +2146,6 @@ static int cpuset_track_online_nodes(struct notifier_block *self, } cgroup_unlock(); - NODEMASK_FREE(oldmems); return NOTIFY_OK; } #endif diff --git a/kernel/crash_dump.c b/kernel/crash_dump.c new file mode 100644 index 00000000000..5f85690285d --- /dev/null +++ b/kernel/crash_dump.c @@ -0,0 +1,34 @@ +#include <linux/kernel.h> +#include <linux/crash_dump.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/module.h> + +/* + * If we have booted due to a crash, max_pfn will be a very low value. We need + * to know the amount of memory that the previous kernel used. + */ +unsigned long saved_max_pfn; + +/* + * stores the physical address of elf header of crash image + * + * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by + * is_kdump_kernel() to determine if we are booting after a panic. Hence put + * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE. + */ +unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; + +/* + * elfcorehdr= specifies the location of elf core header stored by the crashed + * kernel. This option will be passed by kexec loader to the capture kernel. + */ +static int __init setup_elfcorehdr(char *arg) +{ + char *end; + if (!arg) + return -EINVAL; + elfcorehdr_addr = memparse(arg, &end); + return end > arg ? 0 : -EINVAL; +} +early_param("elfcorehdr", setup_elfcorehdr); diff --git a/kernel/cred.c b/kernel/cred.c index 6a1aa004e37..8093c16b84b 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -35,7 +35,7 @@ static struct kmem_cache *cred_jar; static struct thread_group_cred init_tgcred = { .usage = ATOMIC_INIT(2), .tgid = 0, - .lock = SPIN_LOCK_UNLOCKED, + .lock = __SPIN_LOCK_UNLOCKED(init_cred.tgcred.lock), }; #endif @@ -54,6 +54,7 @@ struct cred init_cred = { .cap_effective = CAP_INIT_EFF_SET, .cap_bset = CAP_INIT_BSET, .user = INIT_USER, + .user_ns = &init_user_ns, .group_info = &init_groups, #ifdef CONFIG_KEYS .tgcred = &init_tgcred, @@ -252,13 +253,13 @@ struct cred *cred_alloc_blank(void) #endif atomic_set(&new->usage, 1); +#ifdef CONFIG_DEBUG_CREDENTIALS + new->magic = CRED_MAGIC; +#endif if (security_cred_alloc_blank(new, GFP_KERNEL) < 0) goto error; -#ifdef CONFIG_DEBUG_CREDENTIALS - new->magic = CRED_MAGIC; -#endif return new; error: @@ -410,6 +411,11 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) goto error_put; } + /* cache user_ns in cred. Doesn't need a refcount because it will + * stay pinned by cred->user + */ + new->user_ns = new->user->user_ns; + #ifdef CONFIG_KEYS /* new threads get their own thread keyrings if their parent already * had one */ @@ -657,6 +663,8 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) validate_creds(old); *new = *old; + atomic_set(&new->usage, 1); + set_cred_subscribers(new, 0); get_uid(new->user); get_group_info(new->group_info); @@ -674,8 +682,6 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon) if (security_prepare_creds(new, old, GFP_KERNEL) < 0) goto error; - atomic_set(&new->usage, 1); - set_cred_subscribers(new, 0); put_cred(old); validate_creds(new); return new; @@ -748,7 +754,11 @@ bool creds_are_invalid(const struct cred *cred) if (cred->magic != CRED_MAGIC) return true; #ifdef CONFIG_SECURITY_SELINUX - if (selinux_is_enabled()) { + /* + * cred->security == NULL if security_cred_alloc_blank() or + * security_prepare_creds() returned an error. + */ + if (selinux_is_enabled() && cred->security) { if ((unsigned long) cred->security < PAGE_SIZE) return true; if ((*(u32 *)cred->security & 0xffffff00) == diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index cefd4a11f6d..bad6786dee8 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -538,7 +538,7 @@ return_normal: /* * For single stepping, try to only enter on the processor - * that was single stepping. To gaurd against a deadlock, the + * that was single stepping. To guard against a deadlock, the * kernel will only try for the value of sstep_tries before * giving up and continuing on. */ diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c index 481a7bd2dfe..a11db956dd6 100644 --- a/kernel/debug/gdbstub.c +++ b/kernel/debug/gdbstub.c @@ -1093,3 +1093,33 @@ int gdbstub_state(struct kgdb_state *ks, char *cmd) put_packet(remcom_out_buffer); return 0; } + +/** + * gdbstub_exit - Send an exit message to GDB + * @status: The exit code to report. + */ +void gdbstub_exit(int status) +{ + unsigned char checksum, ch, buffer[3]; + int loop; + + buffer[0] = 'W'; + buffer[1] = hex_asc_hi(status); + buffer[2] = hex_asc_lo(status); + + dbg_io_ops->write_char('$'); + checksum = 0; + + for (loop = 0; loop < 3; loop++) { + ch = buffer[loop]; + checksum += ch; + dbg_io_ops->write_char(ch); + } + + dbg_io_ops->write_char('#'); + dbg_io_ops->write_char(hex_asc_hi(checksum)); + dbg_io_ops->write_char(hex_asc_lo(checksum)); + + /* make sure the output is flushed, lest the bootloader clobber it */ + dbg_io_ops->flush(); +} diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 37755d62192..be14779bcef 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -78,11 +78,11 @@ static unsigned int kdb_continue_catastrophic; static kdbtab_t *kdb_commands; #define KDB_BASE_CMD_MAX 50 static int kdb_max_commands = KDB_BASE_CMD_MAX; -static kdbtab_t kdb_base_commands[50]; +static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX]; #define for_each_kdbcmd(cmd, num) \ for ((cmd) = kdb_base_commands, (num) = 0; \ num < kdb_max_commands; \ - num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++, num++) + num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++) typedef struct _kdbmsg { int km_diag; /* kdb diagnostic */ @@ -441,9 +441,9 @@ static int kdb_check_regs(void) * symbol name, and offset to the caller. * * The argument may consist of a numeric value (decimal or - * hexidecimal), a symbol name, a register name (preceeded by the + * hexidecimal), a symbol name, a register name (preceded by the * percent sign), an environment variable with a numeric value - * (preceeded by a dollar sign) or a simple arithmetic expression + * (preceded by a dollar sign) or a simple arithmetic expression * consisting of a symbol name, +/-, and a numeric constant value * (offset). * Parameters: @@ -646,7 +646,7 @@ static int kdb_defcmd2(const char *cmdstr, const char *argv0) } if (!s->usable) return KDB_NOTIMP; - s->command = kmalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB); + s->command = kzalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB); if (!s->command) { kdb_printf("Could not allocate new kdb_defcmd table for %s\n", cmdstr); @@ -1335,7 +1335,7 @@ void kdb_print_state(const char *text, int value) * error The hardware-defined error code * reason2 kdb's current reason code. * Initially error but can change - * acording to kdb state. + * according to kdb state. * db_result Result code from break or debug point. * regs The exception frame at time of fault/breakpoint. * should always be valid. @@ -2361,7 +2361,7 @@ static int kdb_pid(int argc, const char **argv) */ static int kdb_ll(int argc, const char **argv) { - int diag; + int diag = 0; unsigned long addr; long offset = 0; unsigned long va; @@ -2400,20 +2400,21 @@ static int kdb_ll(int argc, const char **argv) char buf[80]; if (KDB_FLAG(CMD_INTERRUPT)) - return 0; + goto out; sprintf(buf, "%s " kdb_machreg_fmt "\n", command, va); diag = kdb_parse(buf); if (diag) - return diag; + goto out; addr = va + linkoffset; if (kdb_getword(&va, addr, sizeof(va))) - return 0; + goto out; } - kfree(command); - return 0; +out: + kfree(command); + return diag; } static int kdb_kgdb(int argc, const char **argv) @@ -2739,13 +2740,13 @@ int kdb_register_repeat(char *cmd, } if (kdb_commands) { memcpy(new, kdb_commands, - kdb_max_commands * sizeof(*new)); + (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new)); kfree(kdb_commands); } memset(new + kdb_max_commands, 0, kdb_command_extend * sizeof(*new)); kdb_commands = new; - kp = kdb_commands + kdb_max_commands; + kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX; kdb_max_commands += kdb_command_extend; } @@ -2891,7 +2892,7 @@ static void __init kdb_inittab(void) "Send a signal to a process", 0, KDB_REPEAT_NONE); kdb_register_repeat("summary", kdb_summary, "", "Summarize the system", 4, KDB_REPEAT_NONE); - kdb_register_repeat("per_cpu", kdb_per_cpu, "", + kdb_register_repeat("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]", "Display per_cpu variables", 3, KDB_REPEAT_NONE); kdb_register_repeat("grephelp", kdb_grep_help, "", "Display help on | grep", 0, KDB_REPEAT_NONE); @@ -2913,7 +2914,7 @@ static void __init kdb_cmd_init(void) } } -/* Intialize kdb_printf, breakpoint tables and kdb state */ +/* Initialize kdb_printf, breakpoint tables and kdb state */ void __init kdb_init(int lvl) { static int kdb_init_lvl = KDB_NOT_INITIALIZED; diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c index 6b2485dcb05..5532dd37aa8 100644 --- a/kernel/debug/kdb/kdb_support.c +++ b/kernel/debug/kdb/kdb_support.c @@ -545,7 +545,7 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size) * Mask for process state. * Notes: * The mask folds data from several sources into a single long value, so - * be carefull not to overlap the bits. TASK_* bits are in the LSB, + * be careful not to overlap the bits. TASK_* bits are in the LSB, * special cases like UNRUNNABLE are in the MSB. As of 2.6.10-rc1 there * is no overlap between TASK_* and EXIT_* but that may not always be * true, so EXIT_* bits are shifted left 16 bits before being stored in diff --git a/kernel/events/Makefile b/kernel/events/Makefile new file mode 100644 index 00000000000..1ce23d3d839 --- /dev/null +++ b/kernel/events/Makefile @@ -0,0 +1,6 @@ +ifdef CONFIG_FUNCTION_TRACER +CFLAGS_REMOVE_core.o = -pg +endif + +obj-y := core.o +obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o diff --git a/kernel/perf_event.c b/kernel/events/core.c index 517d827f498..c09767f7db3 100644 --- a/kernel/perf_event.c +++ b/kernel/events/core.c @@ -2,8 +2,8 @@ * Performance events core code: * * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> - * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar - * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> + * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar + * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> * * For licensing details see kernel-base/COPYING @@ -13,6 +13,7 @@ #include <linux/mm.h> #include <linux/cpu.h> #include <linux/smp.h> +#include <linux/idr.h> #include <linux/file.h> #include <linux/poll.h> #include <linux/slab.h> @@ -21,7 +22,9 @@ #include <linux/dcache.h> #include <linux/percpu.h> #include <linux/ptrace.h> +#include <linux/reboot.h> #include <linux/vmstat.h> +#include <linux/device.h> #include <linux/vmalloc.h> #include <linux/hardirq.h> #include <linux/rculist.h> @@ -31,10 +34,100 @@ #include <linux/kernel_stat.h> #include <linux/perf_event.h> #include <linux/ftrace_event.h> +#include <linux/hw_breakpoint.h> #include <asm/irq_regs.h> -atomic_t perf_task_events __read_mostly; +struct remote_function_call { + struct task_struct *p; + int (*func)(void *info); + void *info; + int ret; +}; + +static void remote_function(void *data) +{ + struct remote_function_call *tfc = data; + struct task_struct *p = tfc->p; + + if (p) { + tfc->ret = -EAGAIN; + if (task_cpu(p) != smp_processor_id() || !task_curr(p)) + return; + } + + tfc->ret = tfc->func(tfc->info); +} + +/** + * task_function_call - call a function on the cpu on which a task runs + * @p: the task to evaluate + * @func: the function to be called + * @info: the function call argument + * + * Calls the function @func when the task is currently running. This might + * be on the current CPU, which just calls the function directly + * + * returns: @func return value, or + * -ESRCH - when the process isn't running + * -EAGAIN - when the process moved away + */ +static int +task_function_call(struct task_struct *p, int (*func) (void *info), void *info) +{ + struct remote_function_call data = { + .p = p, + .func = func, + .info = info, + .ret = -ESRCH, /* No such (running) process */ + }; + + if (task_curr(p)) + smp_call_function_single(task_cpu(p), remote_function, &data, 1); + + return data.ret; +} + +/** + * cpu_function_call - call a function on the cpu + * @func: the function to be called + * @info: the function call argument + * + * Calls the function @func on the remote cpu. + * + * returns: @func return value or -ENXIO when the cpu is offline + */ +static int cpu_function_call(int cpu, int (*func) (void *info), void *info) +{ + struct remote_function_call data = { + .p = NULL, + .func = func, + .info = info, + .ret = -ENXIO, /* No such CPU */ + }; + + smp_call_function_single(cpu, remote_function, &data, 1); + + return data.ret; +} + +#define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ + PERF_FLAG_FD_OUTPUT |\ + PERF_FLAG_PID_CGROUP) + +enum event_type_t { + EVENT_FLEXIBLE = 0x1, + EVENT_PINNED = 0x2, + EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, +}; + +/* + * perf_sched_events : >0 events exist + * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu + */ +struct jump_label_key perf_sched_events __read_mostly; +static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); + static atomic_t nr_mmap_events __read_mostly; static atomic_t nr_comm_events __read_mostly; static atomic_t nr_task_events __read_mostly; @@ -52,15 +145,43 @@ static struct srcu_struct pmus_srcu; */ int sysctl_perf_event_paranoid __read_mostly = 1; -int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */ +/* Minimum for 512 kiB + 1 user control page */ +int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ /* * max perf event sample rate */ -int sysctl_perf_event_sample_rate __read_mostly = 100000; +#define DEFAULT_MAX_SAMPLE_RATE 100000 +int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; +static int max_samples_per_tick __read_mostly = + DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); + +int perf_proc_update_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + int ret = proc_dointvec(table, write, buffer, lenp, ppos); + + if (ret || !write) + return ret; + + max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); + + return 0; +} static atomic64_t perf_event_id; +static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, + enum event_type_t event_type); + +static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, + enum event_type_t event_type, + struct task_struct *task); + +static void update_context_time(struct perf_event_context *ctx); +static u64 perf_event_time(struct perf_event *event); + void __weak perf_event_print_debug(void) { } extern __weak const char *perf_pmu_name(void) @@ -68,6 +189,366 @@ extern __weak const char *perf_pmu_name(void) return "pmu"; } +static inline u64 perf_clock(void) +{ + return local_clock(); +} + +static inline struct perf_cpu_context * +__get_cpu_context(struct perf_event_context *ctx) +{ + return this_cpu_ptr(ctx->pmu->pmu_cpu_context); +} + +#ifdef CONFIG_CGROUP_PERF + +/* + * Must ensure cgroup is pinned (css_get) before calling + * this function. In other words, we cannot call this function + * if there is no cgroup event for the current CPU context. + */ +static inline struct perf_cgroup * +perf_cgroup_from_task(struct task_struct *task) +{ + return container_of(task_subsys_state(task, perf_subsys_id), + struct perf_cgroup, css); +} + +static inline bool +perf_cgroup_match(struct perf_event *event) +{ + struct perf_event_context *ctx = event->ctx; + struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); + + return !event->cgrp || event->cgrp == cpuctx->cgrp; +} + +static inline void perf_get_cgroup(struct perf_event *event) +{ + css_get(&event->cgrp->css); +} + +static inline void perf_put_cgroup(struct perf_event *event) +{ + css_put(&event->cgrp->css); +} + +static inline void perf_detach_cgroup(struct perf_event *event) +{ + perf_put_cgroup(event); + event->cgrp = NULL; +} + +static inline int is_cgroup_event(struct perf_event *event) +{ + return event->cgrp != NULL; +} + +static inline u64 perf_cgroup_event_time(struct perf_event *event) +{ + struct perf_cgroup_info *t; + + t = per_cpu_ptr(event->cgrp->info, event->cpu); + return t->time; +} + +static inline void __update_cgrp_time(struct perf_cgroup *cgrp) +{ + struct perf_cgroup_info *info; + u64 now; + + now = perf_clock(); + + info = this_cpu_ptr(cgrp->info); + + info->time += now - info->timestamp; + info->timestamp = now; +} + +static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) +{ + struct perf_cgroup *cgrp_out = cpuctx->cgrp; + if (cgrp_out) + __update_cgrp_time(cgrp_out); +} + +static inline void update_cgrp_time_from_event(struct perf_event *event) +{ + struct perf_cgroup *cgrp; + + /* + * ensure we access cgroup data only when needed and + * when we know the cgroup is pinned (css_get) + */ + if (!is_cgroup_event(event)) + return; + + cgrp = perf_cgroup_from_task(current); + /* + * Do not update time when cgroup is not active + */ + if (cgrp == event->cgrp) + __update_cgrp_time(event->cgrp); +} + +static inline void +perf_cgroup_set_timestamp(struct task_struct *task, + struct perf_event_context *ctx) +{ + struct perf_cgroup *cgrp; + struct perf_cgroup_info *info; + + /* + * ctx->lock held by caller + * ensure we do not access cgroup data + * unless we have the cgroup pinned (css_get) + */ + if (!task || !ctx->nr_cgroups) + return; + + cgrp = perf_cgroup_from_task(task); + info = this_cpu_ptr(cgrp->info); + info->timestamp = ctx->timestamp; +} + +#define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ +#define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ + +/* + * reschedule events based on the cgroup constraint of task. + * + * mode SWOUT : schedule out everything + * mode SWIN : schedule in based on cgroup for next + */ +void perf_cgroup_switch(struct task_struct *task, int mode) +{ + struct perf_cpu_context *cpuctx; + struct pmu *pmu; + unsigned long flags; + + /* + * disable interrupts to avoid geting nr_cgroup + * changes via __perf_event_disable(). Also + * avoids preemption. + */ + local_irq_save(flags); + + /* + * we reschedule only in the presence of cgroup + * constrained events. + */ + rcu_read_lock(); + + list_for_each_entry_rcu(pmu, &pmus, entry) { + + cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); + + perf_pmu_disable(cpuctx->ctx.pmu); + + /* + * perf_cgroup_events says at least one + * context on this CPU has cgroup events. + * + * ctx->nr_cgroups reports the number of cgroup + * events for a context. + */ + if (cpuctx->ctx.nr_cgroups > 0) { + + if (mode & PERF_CGROUP_SWOUT) { + cpu_ctx_sched_out(cpuctx, EVENT_ALL); + /* + * must not be done before ctxswout due + * to event_filter_match() in event_sched_out() + */ + cpuctx->cgrp = NULL; + } + + if (mode & PERF_CGROUP_SWIN) { + WARN_ON_ONCE(cpuctx->cgrp); + /* set cgrp before ctxsw in to + * allow event_filter_match() to not + * have to pass task around + */ + cpuctx->cgrp = perf_cgroup_from_task(task); + cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); + } + } + + perf_pmu_enable(cpuctx->ctx.pmu); + } + + rcu_read_unlock(); + + local_irq_restore(flags); +} + +static inline void perf_cgroup_sched_out(struct task_struct *task) +{ + perf_cgroup_switch(task, PERF_CGROUP_SWOUT); +} + +static inline void perf_cgroup_sched_in(struct task_struct *task) +{ + perf_cgroup_switch(task, PERF_CGROUP_SWIN); +} + +static inline int perf_cgroup_connect(int fd, struct perf_event *event, + struct perf_event_attr *attr, + struct perf_event *group_leader) +{ + struct perf_cgroup *cgrp; + struct cgroup_subsys_state *css; + struct file *file; + int ret = 0, fput_needed; + + file = fget_light(fd, &fput_needed); + if (!file) + return -EBADF; + + css = cgroup_css_from_dir(file, perf_subsys_id); + if (IS_ERR(css)) { + ret = PTR_ERR(css); + goto out; + } + + cgrp = container_of(css, struct perf_cgroup, css); + event->cgrp = cgrp; + + /* must be done before we fput() the file */ + perf_get_cgroup(event); + + /* + * all events in a group must monitor + * the same cgroup because a task belongs + * to only one perf cgroup at a time + */ + if (group_leader && group_leader->cgrp != cgrp) { + perf_detach_cgroup(event); + ret = -EINVAL; + } +out: + fput_light(file, fput_needed); + return ret; +} + +static inline void +perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) +{ + struct perf_cgroup_info *t; + t = per_cpu_ptr(event->cgrp->info, event->cpu); + event->shadow_ctx_time = now - t->timestamp; +} + +static inline void +perf_cgroup_defer_enabled(struct perf_event *event) +{ + /* + * when the current task's perf cgroup does not match + * the event's, we need to remember to call the + * perf_mark_enable() function the first time a task with + * a matching perf cgroup is scheduled in. + */ + if (is_cgroup_event(event) && !perf_cgroup_match(event)) + event->cgrp_defer_enabled = 1; +} + +static inline void +perf_cgroup_mark_enabled(struct perf_event *event, + struct perf_event_context *ctx) +{ + struct perf_event *sub; + u64 tstamp = perf_event_time(event); + + if (!event->cgrp_defer_enabled) + return; + + event->cgrp_defer_enabled = 0; + + event->tstamp_enabled = tstamp - event->total_time_enabled; + list_for_each_entry(sub, &event->sibling_list, group_entry) { + if (sub->state >= PERF_EVENT_STATE_INACTIVE) { + sub->tstamp_enabled = tstamp - sub->total_time_enabled; + sub->cgrp_defer_enabled = 0; + } + } +} +#else /* !CONFIG_CGROUP_PERF */ + +static inline bool +perf_cgroup_match(struct perf_event *event) +{ + return true; +} + +static inline void perf_detach_cgroup(struct perf_event *event) +{} + +static inline int is_cgroup_event(struct perf_event *event) +{ + return 0; +} + +static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) +{ + return 0; +} + +static inline void update_cgrp_time_from_event(struct perf_event *event) +{ +} + +static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) +{ +} + +static inline void perf_cgroup_sched_out(struct task_struct *task) +{ +} + +static inline void perf_cgroup_sched_in(struct task_struct *task) +{ +} + +static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, + struct perf_event_attr *attr, + struct perf_event *group_leader) +{ + return -EINVAL; +} + +static inline void +perf_cgroup_set_timestamp(struct task_struct *task, + struct perf_event_context *ctx) +{ +} + +void +perf_cgroup_switch(struct task_struct *task, struct task_struct *next) +{ +} + +static inline void +perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) +{ +} + +static inline u64 perf_cgroup_event_time(struct perf_event *event) +{ + return 0; +} + +static inline void +perf_cgroup_defer_enabled(struct perf_event *event) +{ +} + +static inline void +perf_cgroup_mark_enabled(struct perf_event *event, + struct perf_event_context *ctx) +{ +} +#endif + void perf_pmu_disable(struct pmu *pmu) { int *count = this_cpu_ptr(pmu->pmu_disable_count); @@ -105,14 +586,6 @@ static void get_ctx(struct perf_event_context *ctx) WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); } -static void free_ctx(struct rcu_head *head) -{ - struct perf_event_context *ctx; - - ctx = container_of(head, struct perf_event_context, rcu_head); - kfree(ctx); -} - static void put_ctx(struct perf_event_context *ctx) { if (atomic_dec_and_test(&ctx->refcount)) { @@ -120,7 +593,7 @@ static void put_ctx(struct perf_event_context *ctx) put_ctx(ctx->parent_ctx); if (ctx->task) put_task_struct(ctx->task); - call_rcu(&ctx->rcu_head, free_ctx); + kfree_rcu(ctx, rcu_head); } } @@ -132,6 +605,28 @@ static void unclone_ctx(struct perf_event_context *ctx) } } +static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) +{ + /* + * only top level events have the pid namespace they were created in + */ + if (event->parent) + event = event->parent; + + return task_tgid_nr_ns(p, event->ns); +} + +static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) +{ + /* + * only top level events have the pid namespace they were created in + */ + if (event->parent) + event = event->parent; + + return task_pid_nr_ns(p, event->ns); +} + /* * If we inherit events we want to return the parent event id * to userspace. @@ -211,12 +706,6 @@ static void perf_unpin_context(struct perf_event_context *ctx) raw_spin_lock_irqsave(&ctx->lock, flags); --ctx->pin_count; raw_spin_unlock_irqrestore(&ctx->lock, flags); - put_ctx(ctx); -} - -static inline u64 perf_clock(void) -{ - return local_clock(); } /* @@ -230,6 +719,16 @@ static void update_context_time(struct perf_event_context *ctx) ctx->timestamp = now; } +static u64 perf_event_time(struct perf_event *event) +{ + struct perf_event_context *ctx = event->ctx; + + if (is_cgroup_event(event)) + return perf_cgroup_event_time(event); + + return ctx ? ctx->time : 0; +} + /* * Update the total_time_enabled and total_time_running fields for a event. */ @@ -241,8 +740,19 @@ static void update_event_times(struct perf_event *event) if (event->state < PERF_EVENT_STATE_INACTIVE || event->group_leader->state < PERF_EVENT_STATE_INACTIVE) return; - - if (ctx->is_active) + /* + * in cgroup mode, time_enabled represents + * the time the event was enabled AND active + * tasks were in the monitored cgroup. This is + * independent of the activity of the context as + * there may be a mix of cgroup and non-cgroup events. + * + * That is why we treat cgroup events differently + * here. + */ + if (is_cgroup_event(event)) + run_end = perf_event_time(event); + else if (ctx->is_active) run_end = ctx->time; else run_end = event->tstamp_stopped; @@ -252,9 +762,10 @@ static void update_event_times(struct perf_event *event) if (event->state == PERF_EVENT_STATE_INACTIVE) run_end = event->tstamp_stopped; else - run_end = ctx->time; + run_end = perf_event_time(event); event->total_time_running = run_end - event->tstamp_running; + } /* @@ -303,6 +814,9 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx) list_add_tail(&event->group_entry, list); } + if (is_cgroup_event(event)) + ctx->nr_cgroups++; + list_add_rcu(&event->event_entry, &ctx->event_list); if (!ctx->nr_events) perf_pmu_rotate_start(ctx->pmu); @@ -311,9 +825,84 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx) ctx->nr_stat++; } +/* + * Called at perf_event creation and when events are attached/detached from a + * group. + */ +static void perf_event__read_size(struct perf_event *event) +{ + int entry = sizeof(u64); /* value */ + int size = 0; + int nr = 1; + + if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) + size += sizeof(u64); + + if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) + size += sizeof(u64); + + if (event->attr.read_format & PERF_FORMAT_ID) + entry += sizeof(u64); + + if (event->attr.read_format & PERF_FORMAT_GROUP) { + nr += event->group_leader->nr_siblings; + size += sizeof(u64); + } + + size += entry * nr; + event->read_size = size; +} + +static void perf_event__header_size(struct perf_event *event) +{ + struct perf_sample_data *data; + u64 sample_type = event->attr.sample_type; + u16 size = 0; + + perf_event__read_size(event); + + if (sample_type & PERF_SAMPLE_IP) + size += sizeof(data->ip); + + if (sample_type & PERF_SAMPLE_ADDR) + size += sizeof(data->addr); + + if (sample_type & PERF_SAMPLE_PERIOD) + size += sizeof(data->period); + + if (sample_type & PERF_SAMPLE_READ) + size += event->read_size; + + event->header_size = size; +} + +static void perf_event__id_header_size(struct perf_event *event) +{ + struct perf_sample_data *data; + u64 sample_type = event->attr.sample_type; + u16 size = 0; + + if (sample_type & PERF_SAMPLE_TID) + size += sizeof(data->tid_entry); + + if (sample_type & PERF_SAMPLE_TIME) + size += sizeof(data->time); + + if (sample_type & PERF_SAMPLE_ID) + size += sizeof(data->id); + + if (sample_type & PERF_SAMPLE_STREAM_ID) + size += sizeof(data->stream_id); + + if (sample_type & PERF_SAMPLE_CPU) + size += sizeof(data->cpu_entry); + + event->id_header_size = size; +} + static void perf_group_attach(struct perf_event *event) { - struct perf_event *group_leader = event->group_leader; + struct perf_event *group_leader = event->group_leader, *pos; /* * We can have double attach due to group movement in perf_event_open. @@ -332,6 +921,11 @@ static void perf_group_attach(struct perf_event *event) list_add_tail(&event->group_entry, &group_leader->sibling_list); group_leader->nr_siblings++; + + perf_event__header_size(group_leader); + + list_for_each_entry(pos, &group_leader->sibling_list, group_entry) + perf_event__header_size(pos); } /* @@ -341,6 +935,7 @@ static void perf_group_attach(struct perf_event *event) static void list_del_event(struct perf_event *event, struct perf_event_context *ctx) { + struct perf_cpu_context *cpuctx; /* * We can have double detach due to exit/hot-unplug + close. */ @@ -349,6 +944,18 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx) event->attach_state &= ~PERF_ATTACH_CONTEXT; + if (is_cgroup_event(event)) { + ctx->nr_cgroups--; + cpuctx = __get_cpu_context(ctx); + /* + * if there are no more cgroup events + * then cler cgrp to avoid stale pointer + * in update_cgrp_time_from_cpuctx() + */ + if (!ctx->nr_cgroups) + cpuctx->cgrp = NULL; + } + ctx->nr_events--; if (event->attr.inherit_stat) ctx->nr_stat--; @@ -390,7 +997,7 @@ static void perf_group_detach(struct perf_event *event) if (event->group_leader != event) { list_del_init(&event->group_entry); event->group_leader->nr_siblings--; - return; + goto out; } if (!list_empty(&event->group_entry)) @@ -409,12 +1016,19 @@ static void perf_group_detach(struct perf_event *event) /* Inherit group flags from the previous leader */ sibling->group_flags = event->group_flags; } + +out: + perf_event__header_size(event->group_leader); + + list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) + perf_event__header_size(tmp); } static inline int event_filter_match(struct perf_event *event) { - return event->cpu == -1 || event->cpu == smp_processor_id(); + return (event->cpu == -1 || event->cpu == smp_processor_id()) + && perf_cgroup_match(event); } static void @@ -422,6 +1036,7 @@ event_sched_out(struct perf_event *event, struct perf_cpu_context *cpuctx, struct perf_event_context *ctx) { + u64 tstamp = perf_event_time(event); u64 delta; /* * An event which could not be activated because of @@ -431,9 +1046,9 @@ event_sched_out(struct perf_event *event, */ if (event->state == PERF_EVENT_STATE_INACTIVE && !event_filter_match(event)) { - delta = ctx->time - event->tstamp_stopped; + delta = tstamp - event->tstamp_stopped; event->tstamp_running += delta; - event->tstamp_stopped = ctx->time; + event->tstamp_stopped = tstamp; } if (event->state != PERF_EVENT_STATE_ACTIVE) @@ -444,7 +1059,7 @@ event_sched_out(struct perf_event *event, event->pending_disable = 0; event->state = PERF_EVENT_STATE_OFF; } - event->tstamp_stopped = ctx->time; + event->tstamp_stopped = tstamp; event->pmu->del(event, 0); event->oncpu = -1; @@ -475,47 +1090,30 @@ group_sched_out(struct perf_event *group_event, cpuctx->exclusive = 0; } -static inline struct perf_cpu_context * -__get_cpu_context(struct perf_event_context *ctx) -{ - return this_cpu_ptr(ctx->pmu->pmu_cpu_context); -} - /* * Cross CPU call to remove a performance event * * We disable the event on the hardware level first. After that we * remove it from the context list. */ -static void __perf_event_remove_from_context(void *info) +static int __perf_remove_from_context(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); - /* - * If this is a task context, we need to check whether it is - * the current task context of this cpu. If not it has been - * scheduled out before the smp call arrived. - */ - if (ctx->task && cpuctx->task_ctx != ctx) - return; - raw_spin_lock(&ctx->lock); - event_sched_out(event, cpuctx, ctx); - list_del_event(event, ctx); - raw_spin_unlock(&ctx->lock); + + return 0; } /* * Remove the event from a task's (or a CPU's) list of events. * - * Must be called with ctx->mutex held. - * * CPU events are removed with a smp call. For task events we only * call when the task is on a CPU. * @@ -526,49 +1124,48 @@ static void __perf_event_remove_from_context(void *info) * When called from perf_event_exit_task, it's OK because the * context has been detached from its task. */ -static void perf_event_remove_from_context(struct perf_event *event) +static void perf_remove_from_context(struct perf_event *event) { struct perf_event_context *ctx = event->ctx; struct task_struct *task = ctx->task; + lockdep_assert_held(&ctx->mutex); + if (!task) { /* * Per cpu events are removed via an smp call and * the removal is always successful. */ - smp_call_function_single(event->cpu, - __perf_event_remove_from_context, - event, 1); + cpu_function_call(event->cpu, __perf_remove_from_context, event); return; } retry: - task_oncpu_function_call(task, __perf_event_remove_from_context, - event); + if (!task_function_call(task, __perf_remove_from_context, event)) + return; raw_spin_lock_irq(&ctx->lock); /* - * If the context is active we need to retry the smp call. + * If we failed to find a running task, but find the context active now + * that we've acquired the ctx->lock, retry. */ - if (ctx->nr_active && !list_empty(&event->group_entry)) { + if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); goto retry; } /* - * The lock prevents that this context is scheduled in so we - * can remove the event safely, if the call above did not - * succeed. + * Since the task isn't running, its safe to remove the event, us + * holding the ctx->lock ensures the task won't get scheduled in. */ - if (!list_empty(&event->group_entry)) - list_del_event(event, ctx); + list_del_event(event, ctx); raw_spin_unlock_irq(&ctx->lock); } /* * Cross CPU call to disable a performance event */ -static void __perf_event_disable(void *info) +static int __perf_event_disable(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -577,9 +1174,12 @@ static void __perf_event_disable(void *info) /* * If this is a per-task event, need to check whether this * event's task is the current task on this cpu. + * + * Can trigger due to concurrent perf_event_context_sched_out() + * flipping contexts around. */ if (ctx->task && cpuctx->task_ctx != ctx) - return; + return -EINVAL; raw_spin_lock(&ctx->lock); @@ -589,6 +1189,7 @@ static void __perf_event_disable(void *info) */ if (event->state >= PERF_EVENT_STATE_INACTIVE) { update_context_time(ctx); + update_cgrp_time_from_event(event); update_group_times(event); if (event == event->group_leader) group_sched_out(event, cpuctx, ctx); @@ -598,6 +1199,8 @@ static void __perf_event_disable(void *info) } raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -622,13 +1225,13 @@ void perf_event_disable(struct perf_event *event) /* * Disable the event on the cpu that it's on */ - smp_call_function_single(event->cpu, __perf_event_disable, - event, 1); + cpu_function_call(event->cpu, __perf_event_disable, event); return; } retry: - task_oncpu_function_call(task, __perf_event_disable, event); + if (!task_function_call(task, __perf_event_disable, event)) + return; raw_spin_lock_irq(&ctx->lock); /* @@ -636,6 +1239,11 @@ retry: */ if (event->state == PERF_EVENT_STATE_ACTIVE) { raw_spin_unlock_irq(&ctx->lock); + /* + * Reload the task pointer, it might have been changed by + * a concurrent perf_event_context_sched_out(). + */ + task = ctx->task; goto retry; } @@ -647,20 +1255,71 @@ retry: update_group_times(event); event->state = PERF_EVENT_STATE_OFF; } - raw_spin_unlock_irq(&ctx->lock); } +static void perf_set_shadow_time(struct perf_event *event, + struct perf_event_context *ctx, + u64 tstamp) +{ + /* + * use the correct time source for the time snapshot + * + * We could get by without this by leveraging the + * fact that to get to this function, the caller + * has most likely already called update_context_time() + * and update_cgrp_time_xx() and thus both timestamp + * are identical (or very close). Given that tstamp is, + * already adjusted for cgroup, we could say that: + * tstamp - ctx->timestamp + * is equivalent to + * tstamp - cgrp->timestamp. + * + * Then, in perf_output_read(), the calculation would + * work with no changes because: + * - event is guaranteed scheduled in + * - no scheduled out in between + * - thus the timestamp would be the same + * + * But this is a bit hairy. + * + * So instead, we have an explicit cgroup call to remain + * within the time time source all along. We believe it + * is cleaner and simpler to understand. + */ + if (is_cgroup_event(event)) + perf_cgroup_set_shadow_time(event, tstamp); + else + event->shadow_ctx_time = tstamp - ctx->timestamp; +} + +#define MAX_INTERRUPTS (~0ULL) + +static void perf_log_throttle(struct perf_event *event, int enable); + static int event_sched_in(struct perf_event *event, struct perf_cpu_context *cpuctx, struct perf_event_context *ctx) { + u64 tstamp = perf_event_time(event); + if (event->state <= PERF_EVENT_STATE_OFF) return 0; event->state = PERF_EVENT_STATE_ACTIVE; event->oncpu = smp_processor_id(); + + /* + * Unthrottle events, since we scheduled we might have missed several + * ticks already, also for a heavily scheduling task there is little + * guarantee it'll get a tick in a timely manner. + */ + if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { + perf_log_throttle(event, 1); + event->hw.interrupts = 0; + } + /* * The new state must be visible before we turn it on in the hardware: */ @@ -672,7 +1331,9 @@ event_sched_in(struct perf_event *event, return -EAGAIN; } - event->tstamp_running += ctx->time - event->tstamp_stopped; + event->tstamp_running += tstamp - event->tstamp_stopped; + + perf_set_shadow_time(event, ctx, tstamp); if (!is_software_event(event)) cpuctx->active_oncpu++; @@ -784,19 +1445,24 @@ static int group_can_go_on(struct perf_event *event, static void add_event_to_ctx(struct perf_event *event, struct perf_event_context *ctx) { + u64 tstamp = perf_event_time(event); + list_add_event(event, ctx); perf_group_attach(event); - event->tstamp_enabled = ctx->time; - event->tstamp_running = ctx->time; - event->tstamp_stopped = ctx->time; + event->tstamp_enabled = tstamp; + event->tstamp_running = tstamp; + event->tstamp_stopped = tstamp; } +static void perf_event_context_sched_in(struct perf_event_context *ctx, + struct task_struct *tsk); + /* * Cross CPU call to install and enable a performance event * * Must be called with ctx->mutex held */ -static void __perf_install_in_context(void *info) +static int __perf_install_in_context(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -805,25 +1471,26 @@ static void __perf_install_in_context(void *info) int err; /* - * If this is a task context, we need to check whether it is - * the current task context of this cpu. If not it has been - * scheduled out before the smp call arrived. - * Or possibly this is the right context but it isn't - * on this cpu because it had no events. + * In case we're installing a new context to an already running task, + * could also happen before perf_event_task_sched_in() on architectures + * which do context switches with IRQs enabled. */ - if (ctx->task && cpuctx->task_ctx != ctx) { - if (cpuctx->task_ctx || ctx->task != current) - return; - cpuctx->task_ctx = ctx; - } + if (ctx->task && !cpuctx->task_ctx) + perf_event_context_sched_in(ctx, ctx->task); raw_spin_lock(&ctx->lock); ctx->is_active = 1; update_context_time(ctx); + /* + * update cgrp time only if current cgrp + * matches event->cgrp. Must be done before + * calling add_event_to_ctx() + */ + update_cgrp_time_from_event(event); add_event_to_ctx(event, ctx); - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) goto unlock; /* @@ -860,6 +1527,8 @@ static void __perf_install_in_context(void *info) unlock: raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -871,8 +1540,6 @@ unlock: * If the event is attached to a task which is on a CPU we use a smp * call to enable it in the task context. The task might have been * scheduled away, but we check this in the smp call again. - * - * Must be called with ctx->mutex held. */ static void perf_install_in_context(struct perf_event_context *ctx, @@ -881,6 +1548,8 @@ perf_install_in_context(struct perf_event_context *ctx, { struct task_struct *task = ctx->task; + lockdep_assert_held(&ctx->mutex); + event->ctx = ctx; if (!task) { @@ -888,31 +1557,29 @@ perf_install_in_context(struct perf_event_context *ctx, * Per cpu events are installed via an smp call and * the install is always successful. */ - smp_call_function_single(cpu, __perf_install_in_context, - event, 1); + cpu_function_call(cpu, __perf_install_in_context, event); return; } retry: - task_oncpu_function_call(task, __perf_install_in_context, - event); + if (!task_function_call(task, __perf_install_in_context, event)) + return; raw_spin_lock_irq(&ctx->lock); /* - * we need to retry the smp call. + * If we failed to find a running task, but find the context active now + * that we've acquired the ctx->lock, retry. */ - if (ctx->is_active && list_empty(&event->group_entry)) { + if (ctx->is_active) { raw_spin_unlock_irq(&ctx->lock); goto retry; } /* - * The lock prevents that this context is scheduled in so we - * can add the event safely, if it the call above did not - * succeed. + * Since the task isn't running, its safe to add the event, us holding + * the ctx->lock ensures the task won't get scheduled in. */ - if (list_empty(&event->group_entry)) - add_event_to_ctx(event, ctx); + add_event_to_ctx(event, ctx); raw_spin_unlock_irq(&ctx->lock); } @@ -928,21 +1595,20 @@ static void __perf_event_mark_enabled(struct perf_event *event, struct perf_event_context *ctx) { struct perf_event *sub; + u64 tstamp = perf_event_time(event); event->state = PERF_EVENT_STATE_INACTIVE; - event->tstamp_enabled = ctx->time - event->total_time_enabled; + event->tstamp_enabled = tstamp - event->total_time_enabled; list_for_each_entry(sub, &event->sibling_list, group_entry) { - if (sub->state >= PERF_EVENT_STATE_INACTIVE) { - sub->tstamp_enabled = - ctx->time - sub->total_time_enabled; - } + if (sub->state >= PERF_EVENT_STATE_INACTIVE) + sub->tstamp_enabled = tstamp - sub->total_time_enabled; } } /* * Cross CPU call to enable a performance event */ -static void __perf_event_enable(void *info) +static int __perf_event_enable(void *info) { struct perf_event *event = info; struct perf_event_context *ctx = event->ctx; @@ -950,26 +1616,27 @@ static void __perf_event_enable(void *info) struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); int err; - /* - * If this is a per-task event, need to check whether this - * event's task is the current task on this cpu. - */ - if (ctx->task && cpuctx->task_ctx != ctx) { - if (cpuctx->task_ctx || ctx->task != current) - return; - cpuctx->task_ctx = ctx; - } + if (WARN_ON_ONCE(!ctx->is_active)) + return -EINVAL; raw_spin_lock(&ctx->lock); - ctx->is_active = 1; update_context_time(ctx); if (event->state >= PERF_EVENT_STATE_INACTIVE) goto unlock; + + /* + * set current task's cgroup time reference point + */ + perf_cgroup_set_timestamp(current, ctx); + __perf_event_mark_enabled(event, ctx); - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) { + if (is_cgroup_event(event)) + perf_cgroup_defer_enabled(event); goto unlock; + } /* * If the event is in a group and isn't the group leader, @@ -1002,6 +1669,8 @@ static void __perf_event_enable(void *info) unlock: raw_spin_unlock(&ctx->lock); + + return 0; } /* @@ -1022,8 +1691,7 @@ void perf_event_enable(struct perf_event *event) /* * Enable the event on the cpu that it's on */ - smp_call_function_single(event->cpu, __perf_event_enable, - event, 1); + cpu_function_call(event->cpu, __perf_event_enable, event); return; } @@ -1042,8 +1710,15 @@ void perf_event_enable(struct perf_event *event) event->state = PERF_EVENT_STATE_OFF; retry: + if (!ctx->is_active) { + __perf_event_mark_enabled(event, ctx); + goto out; + } + raw_spin_unlock_irq(&ctx->lock); - task_oncpu_function_call(task, __perf_event_enable, event); + + if (!task_function_call(task, __perf_event_enable, event)) + return; raw_spin_lock_irq(&ctx->lock); @@ -1051,15 +1726,14 @@ retry: * If the context is active and the event is still off, * we need to retry the cross-call. */ - if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) + if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) { + /* + * task could have been flipped by a concurrent + * perf_event_context_sched_out() + */ + task = ctx->task; goto retry; - - /* - * Since we have the lock this context can't be scheduled - * in, so we can change the state safely. - */ - if (event->state == PERF_EVENT_STATE_OFF) - __perf_event_mark_enabled(event, ctx); + } out: raw_spin_unlock_irq(&ctx->lock); @@ -1070,7 +1744,7 @@ static int perf_event_refresh(struct perf_event *event, int refresh) /* * not supported on inherited events */ - if (event->attr.inherit) + if (event->attr.inherit || !is_sampling_event(event)) return -EINVAL; atomic_add(refresh, &event->event_limit); @@ -1079,12 +1753,6 @@ static int perf_event_refresh(struct perf_event *event, int refresh) return 0; } -enum event_type_t { - EVENT_FLEXIBLE = 0x1, - EVENT_PINNED = 0x2, - EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, -}; - static void ctx_sched_out(struct perf_event_context *ctx, struct perf_cpu_context *cpuctx, enum event_type_t event_type) @@ -1097,6 +1765,7 @@ static void ctx_sched_out(struct perf_event_context *ctx, if (likely(!ctx->nr_events)) goto out; update_context_time(ctx); + update_cgrp_time_from_cpuctx(cpuctx); if (!ctx->nr_active) goto out; @@ -1209,8 +1878,8 @@ static void perf_event_sync_stat(struct perf_event_context *ctx, } } -void perf_event_context_sched_out(struct task_struct *task, int ctxn, - struct task_struct *next) +static void perf_event_context_sched_out(struct task_struct *task, int ctxn, + struct task_struct *next) { struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; struct perf_event_context *next_ctx; @@ -1284,10 +1953,16 @@ void __perf_event_task_sched_out(struct task_struct *task, { int ctxn; - perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 1, NULL, 0); - for_each_task_context_nr(ctxn) perf_event_context_sched_out(task, ctxn, next); + + /* + * if cgroup events exist on this CPU, then we need + * to check if we have to switch out PMU state. + * cgroup event are system-wide mode only + */ + if (atomic_read(&__get_cpu_var(perf_cgroup_events))) + perf_cgroup_sched_out(task); } static void task_ctx_sched_out(struct perf_event_context *ctx, @@ -1323,9 +1998,13 @@ ctx_pinned_sched_in(struct perf_event_context *ctx, list_for_each_entry(event, &ctx->pinned_groups, group_entry) { if (event->state <= PERF_EVENT_STATE_OFF) continue; - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) continue; + /* may need to reset tstamp_enabled */ + if (is_cgroup_event(event)) + perf_cgroup_mark_enabled(event, ctx); + if (group_can_go_on(event, cpuctx, 1)) group_sched_in(event, cpuctx, ctx); @@ -1355,9 +2034,13 @@ ctx_flexible_sched_in(struct perf_event_context *ctx, * Listen to the 'cpu' scheduling filter constraint * of events: */ - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) continue; + /* may need to reset tstamp_enabled */ + if (is_cgroup_event(event)) + perf_cgroup_mark_enabled(event, ctx); + if (group_can_go_on(event, cpuctx, can_add_hw)) { if (group_sched_in(event, cpuctx, ctx)) can_add_hw = 0; @@ -1368,15 +2051,19 @@ ctx_flexible_sched_in(struct perf_event_context *ctx, static void ctx_sched_in(struct perf_event_context *ctx, struct perf_cpu_context *cpuctx, - enum event_type_t event_type) + enum event_type_t event_type, + struct task_struct *task) { + u64 now; + raw_spin_lock(&ctx->lock); ctx->is_active = 1; if (likely(!ctx->nr_events)) goto out; - ctx->timestamp = perf_clock(); - + now = perf_clock(); + ctx->timestamp = now; + perf_cgroup_set_timestamp(task, ctx); /* * First go through the list and put on any pinned groups * in order to give them the best chance of going on. @@ -1393,11 +2080,12 @@ out: } static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, - enum event_type_t event_type) + enum event_type_t event_type, + struct task_struct *task) { struct perf_event_context *ctx = &cpuctx->ctx; - ctx_sched_in(ctx, cpuctx, event_type); + ctx_sched_in(ctx, cpuctx, event_type, task); } static void task_ctx_sched_in(struct perf_event_context *ctx, @@ -1405,15 +2093,16 @@ static void task_ctx_sched_in(struct perf_event_context *ctx, { struct perf_cpu_context *cpuctx; - cpuctx = __get_cpu_context(ctx); + cpuctx = __get_cpu_context(ctx); if (cpuctx->task_ctx == ctx) return; - ctx_sched_in(ctx, cpuctx, event_type); + ctx_sched_in(ctx, cpuctx, event_type, NULL); cpuctx->task_ctx = ctx; } -void perf_event_context_sched_in(struct perf_event_context *ctx) +static void perf_event_context_sched_in(struct perf_event_context *ctx, + struct task_struct *task) { struct perf_cpu_context *cpuctx; @@ -1429,9 +2118,9 @@ void perf_event_context_sched_in(struct perf_event_context *ctx) */ cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); - ctx_sched_in(ctx, cpuctx, EVENT_PINNED); - cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE); - ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE); + ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); + cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); + ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); cpuctx->task_ctx = ctx; @@ -1464,14 +2153,17 @@ void __perf_event_task_sched_in(struct task_struct *task) if (likely(!ctx)) continue; - perf_event_context_sched_in(ctx); + perf_event_context_sched_in(ctx, task); } + /* + * if cgroup events exist on this CPU, then we need + * to check if we have to switch in PMU state. + * cgroup event are system-wide mode only + */ + if (atomic_read(&__get_cpu_var(perf_cgroup_events))) + perf_cgroup_sched_in(task); } -#define MAX_INTERRUPTS (~0ULL) - -static void perf_log_throttle(struct perf_event *event, int enable); - static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) { u64 frequency = event->attr.sample_freq; @@ -1499,7 +2191,7 @@ static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) * Reduce accuracy by one bit such that @a and @b converge * to a similar magnitude. */ -#define REDUCE_FLS(a, b) \ +#define REDUCE_FLS(a, b) \ do { \ if (a##_fls > b##_fls) { \ a >>= 1; \ @@ -1582,7 +2274,7 @@ static void perf_ctx_adjust_freq(struct perf_event_context *ctx, u64 period) if (event->state != PERF_EVENT_STATE_ACTIVE) continue; - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) continue; hwc = &event->hw; @@ -1619,8 +2311,12 @@ static void rotate_ctx(struct perf_event_context *ctx) { raw_spin_lock(&ctx->lock); - /* Rotate the first entry last of non-pinned groups */ - list_rotate_left(&ctx->flexible_groups); + /* + * Rotate the first entry last of non-pinned groups. Rotation might be + * disabled by the inheritance code. + */ + if (!ctx->rotate_disable) + list_rotate_left(&ctx->flexible_groups); raw_spin_unlock(&ctx->lock); } @@ -1665,7 +2361,7 @@ static void perf_rotate_context(struct perf_cpu_context *cpuctx) if (ctx) rotate_ctx(ctx); - cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE); + cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, current); if (ctx) task_ctx_sched_in(ctx, EVENT_FLEXIBLE); @@ -1720,6 +2416,14 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx) if (!ctx || !ctx->nr_events) goto out; + /* + * We must ctxsw out cgroup events to avoid conflict + * when invoking perf_task_event_sched_in() later on + * in this function. Otherwise we end up trying to + * ctxswin cgroup events which are already scheduled + * in. + */ + perf_cgroup_sched_out(current); task_ctx_sched_out(ctx, EVENT_ALL); raw_spin_lock(&ctx->lock); @@ -1744,7 +2448,10 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx) raw_spin_unlock(&ctx->lock); - perf_event_context_sched_in(ctx); + /* + * Also calls ctxswin for cgroup events, if any: + */ + perf_event_context_sched_in(ctx, ctx->task); out: local_irq_restore(flags); } @@ -1769,11 +2476,14 @@ static void __perf_event_read(void *info) return; raw_spin_lock(&ctx->lock); - update_context_time(ctx); + if (ctx->is_active) { + update_context_time(ctx); + update_cgrp_time_from_event(event); + } update_event_times(event); + if (event->state == PERF_EVENT_STATE_ACTIVE) + event->pmu->read(event); raw_spin_unlock(&ctx->lock); - - event->pmu->read(event); } static inline u64 perf_event_count(struct perf_event *event) @@ -1800,8 +2510,10 @@ static u64 perf_event_read(struct perf_event *event) * (e.g., thread is blocked), in that case * we cannot update context time */ - if (ctx->is_active) + if (ctx->is_active) { update_context_time(ctx); + update_cgrp_time_from_event(event); + } update_event_times(event); raw_spin_unlock_irqrestore(&ctx->lock, flags); } @@ -1867,8 +2579,7 @@ static int alloc_callchain_buffers(void) * accessed from NMI. Use a temporary manual per cpu allocation * until that gets sorted out. */ - size = sizeof(*entries) + sizeof(struct perf_callchain_entry *) * - num_possible_cpus(); + size = offsetof(struct callchain_cpus_entries, cpu_entries[nr_cpu_ids]); entries = kzalloc(size, GFP_KERNEL); if (!entries) @@ -2069,13 +2780,6 @@ find_lively_task_by_vpid(pid_t vpid) if (!task) return ERR_PTR(-ESRCH); - /* - * Can't attach events to a dying task. - */ - err = -ESRCH; - if (task->flags & PF_EXITING) - goto errout; - /* Reuse ptrace permission checks for now. */ err = -EACCES; if (!ptrace_may_access(task, PTRACE_MODE_READ)) @@ -2088,6 +2792,9 @@ errout: } +/* + * Returns a matching context with refcount and pincount. + */ static struct perf_event_context * find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) { @@ -2096,14 +2803,11 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) unsigned long flags; int ctxn, err; - if (!task && cpu != -1) { + if (!task) { /* Must be root to operate on a CPU event: */ if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); - if (cpu < 0 || cpu >= nr_cpumask_bits) - return ERR_PTR(-EINVAL); - /* * We could be clever and allow to attach a event to an * offline CPU and activate it when the CPU comes up, but @@ -2115,6 +2819,7 @@ find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); ctx = &cpuctx->ctx; get_ctx(ctx); + ++ctx->pin_count; return ctx; } @@ -2128,6 +2833,7 @@ retry: ctx = perf_lock_task_context(task, ctxn, &flags); if (ctx) { unclone_ctx(ctx); + ++ctx->pin_count; raw_spin_unlock_irqrestore(&ctx->lock, flags); } @@ -2139,14 +2845,29 @@ retry: get_ctx(ctx); - if (cmpxchg(&task->perf_event_ctxp[ctxn], NULL, ctx)) { - /* - * We raced with some other task; use - * the context they set. - */ + err = 0; + mutex_lock(&task->perf_event_mutex); + /* + * If it has already passed perf_event_exit_task(). + * we must see PF_EXITING, it takes this mutex too. + */ + if (task->flags & PF_EXITING) + err = -ESRCH; + else if (task->perf_event_ctxp[ctxn]) + err = -EAGAIN; + else { + ++ctx->pin_count; + rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); + } + mutex_unlock(&task->perf_event_mutex); + + if (unlikely(err)) { put_task_struct(task); kfree(ctx); - goto retry; + + if (err == -EAGAIN) + goto retry; + goto errout; } } @@ -2177,7 +2898,7 @@ static void free_event(struct perf_event *event) if (!event->parent) { if (event->attach_state & PERF_ATTACH_TASK) - jump_label_dec(&perf_task_events); + jump_label_dec(&perf_sched_events); if (event->attr.mmap || event->attr.mmap_data) atomic_dec(&nr_mmap_events); if (event->attr.comm) @@ -2186,6 +2907,10 @@ static void free_event(struct perf_event *event) atomic_dec(&nr_task_events); if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) put_callchain_buffers(); + if (is_cgroup_event(event)) { + atomic_dec(&per_cpu(perf_cgroup_events, event->cpu)); + jump_label_dec(&perf_sched_events); + } } if (event->buffer) { @@ -2193,6 +2918,9 @@ static void free_event(struct perf_event *event) event->buffer = NULL; } + if (is_cgroup_event(event)) + perf_detach_cgroup(event); + if (event->destroy) event->destroy(event); @@ -2232,11 +2960,6 @@ int perf_event_release_kernel(struct perf_event *event) raw_spin_unlock_irq(&ctx->lock); mutex_unlock(&ctx->mutex); - mutex_lock(&event->owner->perf_event_mutex); - list_del_init(&event->owner_entry); - mutex_unlock(&event->owner->perf_event_mutex); - put_task_struct(event->owner); - free_event(event); return 0; @@ -2249,35 +2972,44 @@ EXPORT_SYMBOL_GPL(perf_event_release_kernel); static int perf_release(struct inode *inode, struct file *file) { struct perf_event *event = file->private_data; + struct task_struct *owner; file->private_data = NULL; - return perf_event_release_kernel(event); -} - -static int perf_event_read_size(struct perf_event *event) -{ - int entry = sizeof(u64); /* value */ - int size = 0; - int nr = 1; - - if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) - size += sizeof(u64); - - if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) - size += sizeof(u64); - - if (event->attr.read_format & PERF_FORMAT_ID) - entry += sizeof(u64); - - if (event->attr.read_format & PERF_FORMAT_GROUP) { - nr += event->group_leader->nr_siblings; - size += sizeof(u64); + rcu_read_lock(); + owner = ACCESS_ONCE(event->owner); + /* + * Matches the smp_wmb() in perf_event_exit_task(). If we observe + * !owner it means the list deletion is complete and we can indeed + * free this event, otherwise we need to serialize on + * owner->perf_event_mutex. + */ + smp_read_barrier_depends(); + if (owner) { + /* + * Since delayed_put_task_struct() also drops the last + * task reference we can safely take a new reference + * while holding the rcu_read_lock(). + */ + get_task_struct(owner); } + rcu_read_unlock(); - size += entry * nr; + if (owner) { + mutex_lock(&owner->perf_event_mutex); + /* + * We have to re-check the event->owner field, if it is cleared + * we raced with perf_event_exit_task(), acquiring the mutex + * ensured they're done, and we can proceed with freeing the + * event. + */ + if (event->owner) + list_del_init(&event->owner_entry); + mutex_unlock(&owner->perf_event_mutex); + put_task_struct(owner); + } - return size; + return perf_event_release_kernel(event); } u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) @@ -2394,7 +3126,7 @@ perf_read_hw(struct perf_event *event, char __user *buf, size_t count) if (event->state == PERF_EVENT_STATE_ERROR) return 0; - if (count < perf_event_read_size(event)) + if (count < event->read_size) return -ENOSPC; WARN_ON_ONCE(event->ctx->parent_ctx); @@ -2480,7 +3212,7 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) int ret = 0; u64 value; - if (!event->attr.sample_period) + if (!is_sampling_event(event)) return -EINVAL; if (copy_from_user(&value, arg, sizeof(value))) @@ -3271,6 +4003,73 @@ __always_inline void perf_output_copy(struct perf_output_handle *handle, } while (len); } +static void __perf_event_header__init_id(struct perf_event_header *header, + struct perf_sample_data *data, + struct perf_event *event) +{ + u64 sample_type = event->attr.sample_type; + + data->type = sample_type; + header->size += event->id_header_size; + + if (sample_type & PERF_SAMPLE_TID) { + /* namespace issues */ + data->tid_entry.pid = perf_event_pid(event, current); + data->tid_entry.tid = perf_event_tid(event, current); + } + + if (sample_type & PERF_SAMPLE_TIME) + data->time = perf_clock(); + + if (sample_type & PERF_SAMPLE_ID) + data->id = primary_event_id(event); + + if (sample_type & PERF_SAMPLE_STREAM_ID) + data->stream_id = event->id; + + if (sample_type & PERF_SAMPLE_CPU) { + data->cpu_entry.cpu = raw_smp_processor_id(); + data->cpu_entry.reserved = 0; + } +} + +static void perf_event_header__init_id(struct perf_event_header *header, + struct perf_sample_data *data, + struct perf_event *event) +{ + if (event->attr.sample_id_all) + __perf_event_header__init_id(header, data, event); +} + +static void __perf_event__output_id_sample(struct perf_output_handle *handle, + struct perf_sample_data *data) +{ + u64 sample_type = data->type; + + if (sample_type & PERF_SAMPLE_TID) + perf_output_put(handle, data->tid_entry); + + if (sample_type & PERF_SAMPLE_TIME) + perf_output_put(handle, data->time); + + if (sample_type & PERF_SAMPLE_ID) + perf_output_put(handle, data->id); + + if (sample_type & PERF_SAMPLE_STREAM_ID) + perf_output_put(handle, data->stream_id); + + if (sample_type & PERF_SAMPLE_CPU) + perf_output_put(handle, data->cpu_entry); +} + +static void perf_event__output_id_sample(struct perf_event *event, + struct perf_output_handle *handle, + struct perf_sample_data *sample) +{ + if (event->attr.sample_id_all) + __perf_event__output_id_sample(handle, sample); +} + int perf_output_begin(struct perf_output_handle *handle, struct perf_event *event, unsigned int size, int nmi, int sample) @@ -3278,6 +4077,7 @@ int perf_output_begin(struct perf_output_handle *handle, struct perf_buffer *buffer; unsigned long tail, offset, head; int have_lost; + struct perf_sample_data sample_data; struct { struct perf_event_header header; u64 id; @@ -3304,8 +4104,12 @@ int perf_output_begin(struct perf_output_handle *handle, goto out; have_lost = local_read(&buffer->lost); - if (have_lost) - size += sizeof(lost_event); + if (have_lost) { + lost_event.header.size = sizeof(lost_event); + perf_event_header__init_id(&lost_event.header, &sample_data, + event); + size += lost_event.header.size; + } perf_output_get_handle(handle); @@ -3336,11 +4140,11 @@ int perf_output_begin(struct perf_output_handle *handle, if (have_lost) { lost_event.header.type = PERF_RECORD_LOST; lost_event.header.misc = 0; - lost_event.header.size = sizeof(lost_event); lost_event.id = event->id; lost_event.lost = local_xchg(&buffer->lost, 0); perf_output_put(handle, lost_event); + perf_event__output_id_sample(event, handle, &sample_data); } return 0; @@ -3373,30 +4177,9 @@ void perf_output_end(struct perf_output_handle *handle) rcu_read_unlock(); } -static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) -{ - /* - * only top level events have the pid namespace they were created in - */ - if (event->parent) - event = event->parent; - - return task_tgid_nr_ns(p, event->ns); -} - -static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) -{ - /* - * only top level events have the pid namespace they were created in - */ - if (event->parent) - event = event->parent; - - return task_pid_nr_ns(p, event->ns); -} - static void perf_output_read_one(struct perf_output_handle *handle, - struct perf_event *event) + struct perf_event *event, + u64 enabled, u64 running) { u64 read_format = event->attr.read_format; u64 values[4]; @@ -3404,11 +4187,11 @@ static void perf_output_read_one(struct perf_output_handle *handle, values[n++] = perf_event_count(event); if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { - values[n++] = event->total_time_enabled + + values[n++] = enabled + atomic64_read(&event->child_total_time_enabled); } if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { - values[n++] = event->total_time_running + + values[n++] = running + atomic64_read(&event->child_total_time_running); } if (read_format & PERF_FORMAT_ID) @@ -3421,7 +4204,8 @@ static void perf_output_read_one(struct perf_output_handle *handle, * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. */ static void perf_output_read_group(struct perf_output_handle *handle, - struct perf_event *event) + struct perf_event *event, + u64 enabled, u64 running) { struct perf_event *leader = event->group_leader, *sub; u64 read_format = event->attr.read_format; @@ -3431,10 +4215,10 @@ static void perf_output_read_group(struct perf_output_handle *handle, values[n++] = 1 + leader->nr_siblings; if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) - values[n++] = leader->total_time_enabled; + values[n++] = enabled; if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) - values[n++] = leader->total_time_running; + values[n++] = running; if (leader != event) leader->pmu->read(leader); @@ -3459,13 +4243,35 @@ static void perf_output_read_group(struct perf_output_handle *handle, } } +#define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ + PERF_FORMAT_TOTAL_TIME_RUNNING) + static void perf_output_read(struct perf_output_handle *handle, struct perf_event *event) { + u64 enabled = 0, running = 0, now, ctx_time; + u64 read_format = event->attr.read_format; + + /* + * compute total_time_enabled, total_time_running + * based on snapshot values taken when the event + * was last scheduled in. + * + * we cannot simply called update_context_time() + * because of locking issue as we are called in + * NMI context + */ + if (read_format & PERF_FORMAT_TOTAL_TIMES) { + now = perf_clock(); + ctx_time = event->shadow_ctx_time + now; + enabled = ctx_time - event->tstamp_enabled; + running = ctx_time - event->tstamp_running; + } + if (event->attr.read_format & PERF_FORMAT_GROUP) - perf_output_read_group(handle, event); + perf_output_read_group(handle, event, enabled, running); else - perf_output_read_one(handle, event); + perf_output_read_one(handle, event, enabled, running); } void perf_output_sample(struct perf_output_handle *handle, @@ -3545,61 +4351,16 @@ void perf_prepare_sample(struct perf_event_header *header, { u64 sample_type = event->attr.sample_type; - data->type = sample_type; - header->type = PERF_RECORD_SAMPLE; - header->size = sizeof(*header); + header->size = sizeof(*header) + event->header_size; header->misc = 0; header->misc |= perf_misc_flags(regs); - if (sample_type & PERF_SAMPLE_IP) { - data->ip = perf_instruction_pointer(regs); - - header->size += sizeof(data->ip); - } - - if (sample_type & PERF_SAMPLE_TID) { - /* namespace issues */ - data->tid_entry.pid = perf_event_pid(event, current); - data->tid_entry.tid = perf_event_tid(event, current); - - header->size += sizeof(data->tid_entry); - } - - if (sample_type & PERF_SAMPLE_TIME) { - data->time = perf_clock(); - - header->size += sizeof(data->time); - } - - if (sample_type & PERF_SAMPLE_ADDR) - header->size += sizeof(data->addr); - - if (sample_type & PERF_SAMPLE_ID) { - data->id = primary_event_id(event); + __perf_event_header__init_id(header, data, event); - header->size += sizeof(data->id); - } - - if (sample_type & PERF_SAMPLE_STREAM_ID) { - data->stream_id = event->id; - - header->size += sizeof(data->stream_id); - } - - if (sample_type & PERF_SAMPLE_CPU) { - data->cpu_entry.cpu = raw_smp_processor_id(); - data->cpu_entry.reserved = 0; - - header->size += sizeof(data->cpu_entry); - } - - if (sample_type & PERF_SAMPLE_PERIOD) - header->size += sizeof(data->period); - - if (sample_type & PERF_SAMPLE_READ) - header->size += perf_event_read_size(event); + if (sample_type & PERF_SAMPLE_IP) + data->ip = perf_instruction_pointer(regs); if (sample_type & PERF_SAMPLE_CALLCHAIN) { int size = 1; @@ -3664,23 +4425,26 @@ perf_event_read_event(struct perf_event *event, struct task_struct *task) { struct perf_output_handle handle; + struct perf_sample_data sample; struct perf_read_event read_event = { .header = { .type = PERF_RECORD_READ, .misc = 0, - .size = sizeof(read_event) + perf_event_read_size(event), + .size = sizeof(read_event) + event->read_size, }, .pid = perf_event_pid(event, task), .tid = perf_event_tid(event, task), }; int ret; + perf_event_header__init_id(&read_event.header, &sample, event); ret = perf_output_begin(&handle, event, read_event.header.size, 0, 0); if (ret) return; perf_output_put(&handle, read_event); perf_output_read(&handle, event); + perf_event__output_id_sample(event, &handle, &sample); perf_output_end(&handle); } @@ -3710,14 +4474,16 @@ static void perf_event_task_output(struct perf_event *event, struct perf_task_event *task_event) { struct perf_output_handle handle; + struct perf_sample_data sample; struct task_struct *task = task_event->task; - int size, ret; + int ret, size = task_event->event_id.header.size; - size = task_event->event_id.header.size; - ret = perf_output_begin(&handle, event, size, 0, 0); + perf_event_header__init_id(&task_event->event_id.header, &sample, event); + ret = perf_output_begin(&handle, event, + task_event->event_id.header.size, 0, 0); if (ret) - return; + goto out; task_event->event_id.pid = perf_event_pid(event, task); task_event->event_id.ppid = perf_event_pid(event, current); @@ -3727,7 +4493,11 @@ static void perf_event_task_output(struct perf_event *event, perf_output_put(&handle, task_event->event_id); + perf_event__output_id_sample(event, &handle, &sample); + perf_output_end(&handle); +out: + task_event->event_id.header.size = size; } static int perf_event_task_match(struct perf_event *event) @@ -3735,7 +4505,7 @@ static int perf_event_task_match(struct perf_event *event) if (event->state < PERF_EVENT_STATE_INACTIVE) return 0; - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) return 0; if (event->attr.comm || event->attr.mmap || @@ -3766,6 +4536,8 @@ static void perf_event_task_event(struct perf_task_event *task_event) rcu_read_lock(); list_for_each_entry_rcu(pmu, &pmus, entry) { cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); + if (cpuctx->active_pmu != pmu) + goto next; perf_event_task_ctx(&cpuctx->ctx, task_event); ctx = task_event->task_ctx; @@ -3840,11 +4612,16 @@ static void perf_event_comm_output(struct perf_event *event, struct perf_comm_event *comm_event) { struct perf_output_handle handle; + struct perf_sample_data sample; int size = comm_event->event_id.header.size; - int ret = perf_output_begin(&handle, event, size, 0, 0); + int ret; + + perf_event_header__init_id(&comm_event->event_id.header, &sample, event); + ret = perf_output_begin(&handle, event, + comm_event->event_id.header.size, 0, 0); if (ret) - return; + goto out; comm_event->event_id.pid = perf_event_pid(event, comm_event->task); comm_event->event_id.tid = perf_event_tid(event, comm_event->task); @@ -3852,7 +4629,12 @@ static void perf_event_comm_output(struct perf_event *event, perf_output_put(&handle, comm_event->event_id); perf_output_copy(&handle, comm_event->comm, comm_event->comm_size); + + perf_event__output_id_sample(event, &handle, &sample); + perf_output_end(&handle); +out: + comm_event->event_id.header.size = size; } static int perf_event_comm_match(struct perf_event *event) @@ -3860,7 +4642,7 @@ static int perf_event_comm_match(struct perf_event *event) if (event->state < PERF_EVENT_STATE_INACTIVE) return 0; - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) return 0; if (event->attr.comm) @@ -3897,10 +4679,11 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event) comm_event->comm_size = size; comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; - rcu_read_lock(); list_for_each_entry_rcu(pmu, &pmus, entry) { cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); + if (cpuctx->active_pmu != pmu) + goto next; perf_event_comm_ctx(&cpuctx->ctx, comm_event); ctxn = pmu->task_ctx_nr; @@ -3976,11 +4759,15 @@ static void perf_event_mmap_output(struct perf_event *event, struct perf_mmap_event *mmap_event) { struct perf_output_handle handle; + struct perf_sample_data sample; int size = mmap_event->event_id.header.size; - int ret = perf_output_begin(&handle, event, size, 0, 0); + int ret; + perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); + ret = perf_output_begin(&handle, event, + mmap_event->event_id.header.size, 0, 0); if (ret) - return; + goto out; mmap_event->event_id.pid = perf_event_pid(event, current); mmap_event->event_id.tid = perf_event_tid(event, current); @@ -3988,7 +4775,12 @@ static void perf_event_mmap_output(struct perf_event *event, perf_output_put(&handle, mmap_event->event_id); perf_output_copy(&handle, mmap_event->file_name, mmap_event->file_size); + + perf_event__output_id_sample(event, &handle, &sample); + perf_output_end(&handle); +out: + mmap_event->event_id.header.size = size; } static int perf_event_mmap_match(struct perf_event *event, @@ -3998,7 +4790,7 @@ static int perf_event_mmap_match(struct perf_event *event, if (event->state < PERF_EVENT_STATE_INACTIVE) return 0; - if (event->cpu != -1 && event->cpu != smp_processor_id()) + if (!event_filter_match(event)) return 0; if ((!executable && event->attr.mmap_data) || @@ -4086,6 +4878,8 @@ got_name: rcu_read_lock(); list_for_each_entry_rcu(pmu, &pmus, entry) { cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); + if (cpuctx->active_pmu != pmu) + goto next; perf_event_mmap_ctx(&cpuctx->ctx, mmap_event, vma->vm_flags & VM_EXEC); @@ -4141,6 +4935,7 @@ void perf_event_mmap(struct vm_area_struct *vma) static void perf_log_throttle(struct perf_event *event, int enable) { struct perf_output_handle handle; + struct perf_sample_data sample; int ret; struct { @@ -4162,11 +4957,15 @@ static void perf_log_throttle(struct perf_event *event, int enable) if (enable) throttle_event.header.type = PERF_RECORD_UNTHROTTLE; - ret = perf_output_begin(&handle, event, sizeof(throttle_event), 1, 0); + perf_event_header__init_id(&throttle_event.header, &sample, event); + + ret = perf_output_begin(&handle, event, + throttle_event.header.size, 1, 0); if (ret) return; perf_output_put(&handle, throttle_event); + perf_event__output_id_sample(event, &handle, &sample); perf_output_end(&handle); } @@ -4182,26 +4981,21 @@ static int __perf_event_overflow(struct perf_event *event, int nmi, struct hw_perf_event *hwc = &event->hw; int ret = 0; - if (!throttle) { - hwc->interrupts++; - } else { - if (hwc->interrupts != MAX_INTERRUPTS) { - hwc->interrupts++; - if (HZ * hwc->interrupts > - (u64)sysctl_perf_event_sample_rate) { - hwc->interrupts = MAX_INTERRUPTS; - perf_log_throttle(event, 0); - ret = 1; - } - } else { - /* - * Keep re-disabling events even though on the previous - * pass we disabled it - just in case we raced with a - * sched-in and the event got enabled again: - */ + /* + * Non-sampling counters might still use the PMI to fold short + * hardware counters, ignore those. + */ + if (unlikely(!is_sampling_event(event))) + return 0; + + if (unlikely(hwc->interrupts >= max_samples_per_tick)) { + if (throttle) { + hwc->interrupts = MAX_INTERRUPTS; + perf_log_throttle(event, 0); ret = 1; } - } + } else + hwc->interrupts++; if (event->attr.freq) { u64 now = perf_clock(); @@ -4327,7 +5121,7 @@ static void perf_swevent_event(struct perf_event *event, u64 nr, if (!regs) return; - if (!hwc->sample_period) + if (!is_sampling_event(event)) return; if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) @@ -4343,7 +5137,7 @@ static int perf_exclude_event(struct perf_event *event, struct pt_regs *regs) { if (event->hw.state & PERF_HES_STOPPED) - return 0; + return 1; if (regs) { if (event->attr.exclude_user && user_mode(regs)) @@ -4454,7 +5248,7 @@ int perf_swevent_get_recursion_context(void) } EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); -void inline perf_swevent_put_recursion_context(int rctx) +inline void perf_swevent_put_recursion_context(int rctx) { struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); @@ -4490,7 +5284,7 @@ static int perf_swevent_add(struct perf_event *event, int flags) struct hw_perf_event *hwc = &event->hw; struct hlist_head *head; - if (hwc->sample_period) { + if (is_sampling_event(event)) { hwc->last_period = hwc->sample_period; perf_swevent_set_period(event); } @@ -4529,14 +5323,6 @@ swevent_hlist_deref(struct swevent_htable *swhash) lockdep_is_held(&swhash->hlist_mutex)); } -static void swevent_hlist_release_rcu(struct rcu_head *rcu_head) -{ - struct swevent_hlist *hlist; - - hlist = container_of(rcu_head, struct swevent_hlist, rcu_head); - kfree(hlist); -} - static void swevent_hlist_release(struct swevent_htable *swhash) { struct swevent_hlist *hlist = swevent_hlist_deref(swhash); @@ -4545,7 +5331,7 @@ static void swevent_hlist_release(struct swevent_htable *swhash) return; rcu_assign_pointer(swhash->swevent_hlist, NULL); - call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu); + kfree_rcu(hlist, rcu_head); } static void swevent_hlist_put_cpu(struct perf_event *event, int cpu) @@ -4627,7 +5413,7 @@ fail: return err; } -atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX]; +struct jump_label_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; static void sw_perf_event_destroy(struct perf_event *event) { @@ -4655,7 +5441,7 @@ static int perf_swevent_init(struct perf_event *event) break; } - if (event_id > PERF_COUNT_SW_MAX) + if (event_id >= PERF_COUNT_SW_MAX) return -ENOENT; if (!event->parent) { @@ -4699,6 +5485,8 @@ static int perf_tp_event_match(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs) { + if (event->hw.state & PERF_HES_STOPPED) + return 0; /* * All tracepoints are from kernel-space. */ @@ -4747,15 +5535,6 @@ static int perf_tp_event_init(struct perf_event *event) if (event->attr.type != PERF_TYPE_TRACEPOINT) return -ENOENT; - /* - * Raw tracepoint data is a severe data leak, only allow root to - * have these. - */ - if ((event->attr.sample_type & PERF_SAMPLE_RAW) && - perf_paranoid_tracepoint_raw() && - !capable(CAP_SYS_ADMIN)) - return -EPERM; - err = perf_trace_init(event); if (err) return err; @@ -4778,7 +5557,7 @@ static struct pmu perf_tracepoint = { static inline void perf_tp_register(void) { - perf_pmu_register(&perf_tracepoint); + perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); } static int perf_event_set_filter(struct perf_event *event, void __user *arg) @@ -4847,6 +5626,10 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) u64 period; event = container_of(hrtimer, struct perf_event, hw.hrtimer); + + if (event->state != PERF_EVENT_STATE_ACTIVE) + return HRTIMER_NORESTART; + event->pmu->read(event); perf_sample_data_init(&data, 0); @@ -4868,31 +5651,30 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) static void perf_swevent_start_hrtimer(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; + s64 period; - hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - hwc->hrtimer.function = perf_swevent_hrtimer; - if (hwc->sample_period) { - s64 period = local64_read(&hwc->period_left); + if (!is_sampling_event(event)) + return; - if (period) { - if (period < 0) - period = 10000; + period = local64_read(&hwc->period_left); + if (period) { + if (period < 0) + period = 10000; - local64_set(&hwc->period_left, 0); - } else { - period = max_t(u64, 10000, hwc->sample_period); - } - __hrtimer_start_range_ns(&hwc->hrtimer, + local64_set(&hwc->period_left, 0); + } else { + period = max_t(u64, 10000, hwc->sample_period); + } + __hrtimer_start_range_ns(&hwc->hrtimer, ns_to_ktime(period), 0, HRTIMER_MODE_REL_PINNED, 0); - } } static void perf_swevent_cancel_hrtimer(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; - if (hwc->sample_period) { + if (is_sampling_event(event)) { ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); local64_set(&hwc->period_left, ktime_to_ns(remaining)); @@ -4900,6 +5682,30 @@ static void perf_swevent_cancel_hrtimer(struct perf_event *event) } } +static void perf_swevent_init_hrtimer(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + + if (!is_sampling_event(event)) + return; + + hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + hwc->hrtimer.function = perf_swevent_hrtimer; + + /* + * Since hrtimers have a fixed rate, we can do a static freq->period + * mapping and avoid the whole period adjust feedback stuff. + */ + if (event->attr.freq) { + long freq = event->attr.sample_freq; + + event->attr.sample_period = NSEC_PER_SEC / freq; + hwc->sample_period = event->attr.sample_period; + local64_set(&hwc->period_left, hwc->sample_period); + event->attr.freq = 0; + } +} + /* * Software event: cpu wall time clock */ @@ -4952,6 +5758,8 @@ static int cpu_clock_event_init(struct perf_event *event) if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) return -ENOENT; + perf_swevent_init_hrtimer(event); + return 0; } @@ -5007,16 +5815,9 @@ static void task_clock_event_del(struct perf_event *event, int flags) static void task_clock_event_read(struct perf_event *event) { - u64 time; - - if (!in_nmi()) { - update_context_time(event->ctx); - time = event->ctx->time; - } else { - u64 now = perf_clock(); - u64 delta = now - event->ctx->timestamp; - time = event->ctx->time + delta; - } + u64 now = perf_clock(); + u64 delta = now - event->ctx->timestamp; + u64 time = event->ctx->time + delta; task_clock_event_update(event, time); } @@ -5029,6 +5830,8 @@ static int task_clock_event_init(struct perf_event *event) if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) return -ENOENT; + perf_swevent_init_hrtimer(event); + return 0; } @@ -5087,25 +5890,96 @@ static void *find_pmu_context(int ctxn) return NULL; } -static void free_pmu_context(void * __percpu cpu_context) +static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) { - struct pmu *pmu; + int cpu; + + for_each_possible_cpu(cpu) { + struct perf_cpu_context *cpuctx; + + cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); + + if (cpuctx->active_pmu == old_pmu) + cpuctx->active_pmu = pmu; + } +} + +static void free_pmu_context(struct pmu *pmu) +{ + struct pmu *i; mutex_lock(&pmus_lock); /* * Like a real lame refcount. */ - list_for_each_entry(pmu, &pmus, entry) { - if (pmu->pmu_cpu_context == cpu_context) + list_for_each_entry(i, &pmus, entry) { + if (i->pmu_cpu_context == pmu->pmu_cpu_context) { + update_pmu_context(i, pmu); goto out; + } } - free_percpu(cpu_context); + free_percpu(pmu->pmu_cpu_context); out: mutex_unlock(&pmus_lock); } +static struct idr pmu_idr; + +static ssize_t +type_show(struct device *dev, struct device_attribute *attr, char *page) +{ + struct pmu *pmu = dev_get_drvdata(dev); + + return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); +} + +static struct device_attribute pmu_dev_attrs[] = { + __ATTR_RO(type), + __ATTR_NULL, +}; + +static int pmu_bus_running; +static struct bus_type pmu_bus = { + .name = "event_source", + .dev_attrs = pmu_dev_attrs, +}; + +static void pmu_dev_release(struct device *dev) +{ + kfree(dev); +} + +static int pmu_dev_alloc(struct pmu *pmu) +{ + int ret = -ENOMEM; + + pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); + if (!pmu->dev) + goto out; + + device_initialize(pmu->dev); + ret = dev_set_name(pmu->dev, "%s", pmu->name); + if (ret) + goto free_dev; + + dev_set_drvdata(pmu->dev, pmu); + pmu->dev->bus = &pmu_bus; + pmu->dev->release = pmu_dev_release; + ret = device_add(pmu->dev); + if (ret) + goto free_dev; + +out: + return ret; + +free_dev: + put_device(pmu->dev); + goto out; +} -int perf_pmu_register(struct pmu *pmu) +static struct lock_class_key cpuctx_mutex; + +int perf_pmu_register(struct pmu *pmu, char *name, int type) { int cpu, ret; @@ -5115,23 +5989,50 @@ int perf_pmu_register(struct pmu *pmu) if (!pmu->pmu_disable_count) goto unlock; + pmu->type = -1; + if (!name) + goto skip_type; + pmu->name = name; + + if (type < 0) { + int err = idr_pre_get(&pmu_idr, GFP_KERNEL); + if (!err) + goto free_pdc; + + err = idr_get_new_above(&pmu_idr, pmu, PERF_TYPE_MAX, &type); + if (err) { + ret = err; + goto free_pdc; + } + } + pmu->type = type; + + if (pmu_bus_running) { + ret = pmu_dev_alloc(pmu); + if (ret) + goto free_idr; + } + +skip_type: pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); if (pmu->pmu_cpu_context) goto got_cpu_context; pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); if (!pmu->pmu_cpu_context) - goto free_pdc; + goto free_dev; for_each_possible_cpu(cpu) { struct perf_cpu_context *cpuctx; cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); __perf_event_init_context(&cpuctx->ctx); + lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); cpuctx->ctx.type = cpu_context; cpuctx->ctx.pmu = pmu; cpuctx->jiffies_interval = 1; INIT_LIST_HEAD(&cpuctx->rotation_list); + cpuctx->active_pmu = pmu; } got_cpu_context: @@ -5164,6 +6065,14 @@ unlock: return ret; +free_dev: + device_del(pmu->dev); + put_device(pmu->dev); + +free_idr: + if (pmu->type >= PERF_TYPE_MAX) + idr_remove(&pmu_idr, pmu->type); + free_pdc: free_percpu(pmu->pmu_disable_count); goto unlock; @@ -5183,17 +6092,33 @@ void perf_pmu_unregister(struct pmu *pmu) synchronize_rcu(); free_percpu(pmu->pmu_disable_count); - free_pmu_context(pmu->pmu_cpu_context); + if (pmu->type >= PERF_TYPE_MAX) + idr_remove(&pmu_idr, pmu->type); + device_del(pmu->dev); + put_device(pmu->dev); + free_pmu_context(pmu); } struct pmu *perf_init_event(struct perf_event *event) { struct pmu *pmu = NULL; int idx; + int ret; idx = srcu_read_lock(&pmus_srcu); + + rcu_read_lock(); + pmu = idr_find(&pmu_idr, event->attr.type); + rcu_read_unlock(); + if (pmu) { + ret = pmu->event_init(event); + if (ret) + pmu = ERR_PTR(ret); + goto unlock; + } + list_for_each_entry_rcu(pmu, &pmus, entry) { - int ret = pmu->event_init(event); + ret = pmu->event_init(event); if (!ret) goto unlock; @@ -5224,6 +6149,11 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, struct hw_perf_event *hwc; long err; + if ((unsigned)cpu >= nr_cpu_ids) { + if (!task || cpu != -1) + return ERR_PTR(-EINVAL); + } + event = kzalloc(sizeof(*event), GFP_KERNEL); if (!event) return ERR_PTR(-ENOMEM); @@ -5272,7 +6202,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, if (!overflow_handler && parent_event) overflow_handler = parent_event->overflow_handler; - + event->overflow_handler = overflow_handler; if (attr->disabled) @@ -5314,7 +6244,7 @@ done: if (!event->parent) { if (event->attach_state & PERF_ATTACH_TASK) - jump_label_inc(&perf_task_events); + jump_label_inc(&perf_sched_events); if (event->attr.mmap || event->attr.mmap_data) atomic_inc(&nr_mmap_events); if (event->attr.comm) @@ -5489,7 +6419,7 @@ SYSCALL_DEFINE5(perf_event_open, int err; /* for future expandability... */ - if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT)) + if (flags & ~PERF_FLAG_ALL) return -EINVAL; err = perf_copy_attr(attr_uptr, &attr); @@ -5506,6 +6436,15 @@ SYSCALL_DEFINE5(perf_event_open, return -EINVAL; } + /* + * In cgroup mode, the pid argument is used to pass the fd + * opened to the cgroup directory in cgroupfs. The cpu argument + * designates the cpu on which to monitor threads from that + * cgroup. + */ + if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) + return -EINVAL; + event_fd = get_unused_fd_flags(O_RDWR); if (event_fd < 0) return event_fd; @@ -5523,7 +6462,7 @@ SYSCALL_DEFINE5(perf_event_open, group_leader = NULL; } - if (pid != -1) { + if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { task = find_lively_task_by_vpid(pid); if (IS_ERR(task)) { err = PTR_ERR(task); @@ -5537,6 +6476,19 @@ SYSCALL_DEFINE5(perf_event_open, goto err_task; } + if (flags & PERF_FLAG_PID_CGROUP) { + err = perf_cgroup_connect(pid, event, &attr, group_leader); + if (err) + goto err_alloc; + /* + * one more event: + * - that has cgroup constraint on event->cpu + * - that may need work on context switch + */ + atomic_inc(&per_cpu(perf_cgroup_events, event->cpu)); + jump_label_inc(&perf_sched_events); + } + /* * Special case software events and allow them to be part of * any hardware group. @@ -5575,6 +6527,11 @@ SYSCALL_DEFINE5(perf_event_open, goto err_alloc; } + if (task) { + put_task_struct(task); + task = NULL; + } + /* * Look up the group leader (we will attach this event to it): */ @@ -5622,10 +6579,10 @@ SYSCALL_DEFINE5(perf_event_open, struct perf_event_context *gctx = group_leader->ctx; mutex_lock(&gctx->mutex); - perf_event_remove_from_context(group_leader); + perf_remove_from_context(group_leader); list_for_each_entry(sibling, &group_leader->sibling_list, group_entry) { - perf_event_remove_from_context(sibling); + perf_remove_from_context(sibling); put_ctx(gctx); } mutex_unlock(&gctx->mutex); @@ -5648,15 +6605,22 @@ SYSCALL_DEFINE5(perf_event_open, perf_install_in_context(ctx, event, cpu); ++ctx->generation; + perf_unpin_context(ctx); mutex_unlock(&ctx->mutex); event->owner = current; - get_task_struct(current); + mutex_lock(¤t->perf_event_mutex); list_add_tail(&event->owner_entry, ¤t->perf_event_list); mutex_unlock(¤t->perf_event_mutex); /* + * Precalculate sample_data sizes + */ + perf_event__header_size(event); + perf_event__id_header_size(event); + + /* * Drop the reference on the group_event after placing the * new event on the sibling_list. This ensures destruction * of the group leader will find the pointer to itself in @@ -5667,6 +6631,7 @@ SYSCALL_DEFINE5(perf_event_open, return event_fd; err_context: + perf_unpin_context(ctx); put_ctx(ctx); err_alloc: free_event(event); @@ -5717,14 +6682,9 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, mutex_lock(&ctx->mutex); perf_install_in_context(ctx, event, cpu); ++ctx->generation; + perf_unpin_context(ctx); mutex_unlock(&ctx->mutex); - event->owner = current; - get_task_struct(current); - mutex_lock(¤t->perf_event_mutex); - list_add_tail(&event->owner_entry, ¤t->perf_event_list); - mutex_unlock(¤t->perf_event_mutex); - return event; err_free: @@ -5774,17 +6734,20 @@ __perf_event_exit_task(struct perf_event *child_event, struct perf_event_context *child_ctx, struct task_struct *child) { - struct perf_event *parent_event; + if (child_event->parent) { + raw_spin_lock_irq(&child_ctx->lock); + perf_group_detach(child_event); + raw_spin_unlock_irq(&child_ctx->lock); + } - perf_event_remove_from_context(child_event); + perf_remove_from_context(child_event); - parent_event = child_event->parent; /* - * It can happen that parent exits first, and has events + * It can happen that the parent exits first, and has events * that are still around due to the child reference. These - * events need to be zapped - but otherwise linger. + * events need to be zapped. */ - if (parent_event) { + if (child_event->parent) { sync_child_event(child_event, child); free_event(child_event); } @@ -5808,7 +6771,7 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn) * scheduled, so we are now safe from rescheduling changing * our context. */ - child_ctx = child->perf_event_ctxp[ctxn]; + child_ctx = rcu_dereference_raw(child->perf_event_ctxp[ctxn]); task_ctx_sched_out(child_ctx, EVENT_ALL); /* @@ -5875,8 +6838,24 @@ again: */ void perf_event_exit_task(struct task_struct *child) { + struct perf_event *event, *tmp; int ctxn; + mutex_lock(&child->perf_event_mutex); + list_for_each_entry_safe(event, tmp, &child->perf_event_list, + owner_entry) { + list_del_init(&event->owner_entry); + + /* + * Ensure the list deletion is visible before we clear + * the owner, closes a race against perf_release() where + * we need to serialize on the owner->perf_event_mutex. + */ + smp_wmb(); + event->owner = NULL; + } + mutex_unlock(&child->perf_event_mutex); + for_each_task_context_nr(ctxn) perf_event_exit_task_context(child, ctxn); } @@ -5999,6 +6978,12 @@ inherit_event(struct perf_event *parent_event, child_event->overflow_handler = parent_event->overflow_handler; /* + * Precalculate sample_data sizes + */ + perf_event__header_size(child_event); + perf_event__id_header_size(child_event); + + /* * Link it up in the child's context: */ raw_spin_lock_irqsave(&child_ctx->lock, flags); @@ -6061,7 +7046,7 @@ inherit_task_group(struct perf_event *event, struct task_struct *parent, return 0; } - child_ctx = child->perf_event_ctxp[ctxn]; + child_ctx = child->perf_event_ctxp[ctxn]; if (!child_ctx) { /* * This is executed from the parent task context, so @@ -6096,13 +7081,9 @@ int perf_event_init_context(struct task_struct *child, int ctxn) struct perf_event *event; struct task_struct *parent = current; int inherited_all = 1; + unsigned long flags; int ret = 0; - child->perf_event_ctxp[ctxn] = NULL; - - mutex_init(&child->perf_event_mutex); - INIT_LIST_HEAD(&child->perf_event_list); - if (likely(!parent->perf_event_ctxp[ctxn])) return 0; @@ -6136,6 +7117,15 @@ int perf_event_init_context(struct task_struct *child, int ctxn) break; } + /* + * We can't hold ctx->lock when iterating the ->flexible_group list due + * to allocations, but we need to prevent rotation because + * rotate_ctx() will change the list from interrupt context. + */ + raw_spin_lock_irqsave(&parent_ctx->lock, flags); + parent_ctx->rotate_disable = 1; + raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); + list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { ret = inherit_task_group(event, parent, parent_ctx, child, ctxn, &inherited_all); @@ -6143,18 +7133,20 @@ int perf_event_init_context(struct task_struct *child, int ctxn) break; } + raw_spin_lock_irqsave(&parent_ctx->lock, flags); + parent_ctx->rotate_disable = 0; + child_ctx = child->perf_event_ctxp[ctxn]; if (child_ctx && inherited_all) { /* * Mark the child context as a clone of the parent * context, or of whatever the parent is a clone of. - * Note that if the parent is a clone, it could get - * uncloned at any point, but that doesn't matter - * because the list of events and the generation - * count can't have changed since we took the mutex. + * + * Note that if the parent is a clone, the holding of + * parent_ctx->lock avoids it from being uncloned. */ - cloned_ctx = rcu_dereference(parent_ctx->parent_ctx); + cloned_ctx = parent_ctx->parent_ctx; if (cloned_ctx) { child_ctx->parent_ctx = cloned_ctx; child_ctx->parent_gen = parent_ctx->parent_gen; @@ -6165,9 +7157,11 @@ int perf_event_init_context(struct task_struct *child, int ctxn) get_ctx(child_ctx->parent_ctx); } + raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); mutex_unlock(&parent_ctx->mutex); perf_unpin_context(parent_ctx); + put_ctx(parent_ctx); return ret; } @@ -6179,6 +7173,10 @@ int perf_event_init_task(struct task_struct *child) { int ctxn, ret; + memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); + mutex_init(&child->perf_event_mutex); + INIT_LIST_HEAD(&child->perf_event_list); + for_each_task_context_nr(ctxn) { ret = perf_event_init_context(child, ctxn); if (ret) @@ -6215,7 +7213,7 @@ static void __cpuinit perf_event_init_cpu(int cpu) mutex_unlock(&swhash->hlist_mutex); } -#ifdef CONFIG_HOTPLUG_CPU +#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC static void perf_pmu_rotate_stop(struct pmu *pmu) { struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); @@ -6233,9 +7231,9 @@ static void __perf_event_exit_context(void *__info) perf_pmu_rotate_stop(ctx->pmu); list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry) - __perf_event_remove_from_context(event); + __perf_remove_from_context(event); list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry) - __perf_event_remove_from_context(event); + __perf_remove_from_context(event); } static void perf_event_exit_cpu_context(int cpu) @@ -6269,6 +7267,26 @@ static void perf_event_exit_cpu(int cpu) static inline void perf_event_exit_cpu(int cpu) { } #endif +static int +perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) +{ + int cpu; + + for_each_online_cpu(cpu) + perf_event_exit_cpu(cpu); + + return NOTIFY_OK; +} + +/* + * Run the perf reboot notifier at the very last possible moment so that + * the generic watchdog code runs as long as possible. + */ +static struct notifier_block perf_reboot_notifier = { + .notifier_call = perf_reboot, + .priority = INT_MIN, +}; + static int __cpuinit perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { @@ -6295,11 +7313,127 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) void __init perf_event_init(void) { + int ret; + + idr_init(&pmu_idr); + perf_event_init_all_cpus(); init_srcu_struct(&pmus_srcu); - perf_pmu_register(&perf_swevent); - perf_pmu_register(&perf_cpu_clock); - perf_pmu_register(&perf_task_clock); + perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); + perf_pmu_register(&perf_cpu_clock, NULL, -1); + perf_pmu_register(&perf_task_clock, NULL, -1); perf_tp_register(); perf_cpu_notifier(perf_cpu_notify); + register_reboot_notifier(&perf_reboot_notifier); + + ret = init_hw_breakpoint(); + WARN(ret, "hw_breakpoint initialization failed with: %d", ret); +} + +static int __init perf_event_sysfs_init(void) +{ + struct pmu *pmu; + int ret; + + mutex_lock(&pmus_lock); + + ret = bus_register(&pmu_bus); + if (ret) + goto unlock; + + list_for_each_entry(pmu, &pmus, entry) { + if (!pmu->name || pmu->type < 0) + continue; + + ret = pmu_dev_alloc(pmu); + WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); + } + pmu_bus_running = 1; + ret = 0; + +unlock: + mutex_unlock(&pmus_lock); + + return ret; +} +device_initcall(perf_event_sysfs_init); + +#ifdef CONFIG_CGROUP_PERF +static struct cgroup_subsys_state *perf_cgroup_create( + struct cgroup_subsys *ss, struct cgroup *cont) +{ + struct perf_cgroup *jc; + + jc = kzalloc(sizeof(*jc), GFP_KERNEL); + if (!jc) + return ERR_PTR(-ENOMEM); + + jc->info = alloc_percpu(struct perf_cgroup_info); + if (!jc->info) { + kfree(jc); + return ERR_PTR(-ENOMEM); + } + + return &jc->css; +} + +static void perf_cgroup_destroy(struct cgroup_subsys *ss, + struct cgroup *cont) +{ + struct perf_cgroup *jc; + jc = container_of(cgroup_subsys_state(cont, perf_subsys_id), + struct perf_cgroup, css); + free_percpu(jc->info); + kfree(jc); +} + +static int __perf_cgroup_move(void *info) +{ + struct task_struct *task = info; + perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); + return 0; +} + +static void perf_cgroup_move(struct task_struct *task) +{ + task_function_call(task, __perf_cgroup_move, task); } + +static void perf_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup *old_cgrp, struct task_struct *task, + bool threadgroup) +{ + perf_cgroup_move(task); + if (threadgroup) { + struct task_struct *c; + rcu_read_lock(); + list_for_each_entry_rcu(c, &task->thread_group, thread_group) { + perf_cgroup_move(c); + } + rcu_read_unlock(); + } +} + +static void perf_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup *old_cgrp, struct task_struct *task) +{ + /* + * cgroup_exit() is called in the copy_process() failure path. + * Ignore this case since the task hasn't ran yet, this avoids + * trying to poke a half freed task state from generic code. + */ + if (!(task->flags & PF_EXITING)) + return; + + perf_cgroup_move(task); +} + +struct cgroup_subsys perf_subsys = { + .name = "perf_event", + .subsys_id = perf_subsys_id, + .create = perf_cgroup_create, + .destroy = perf_cgroup_destroy, + .exit = perf_cgroup_exit, + .attach = perf_cgroup_attach, +}; +#endif /* CONFIG_CGROUP_PERF */ diff --git a/kernel/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index 2c9120f0afc..086adf25a55 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -620,7 +620,7 @@ static struct pmu perf_breakpoint = { .read = hw_breakpoint_pmu_read, }; -static int __init init_hw_breakpoint(void) +int __init init_hw_breakpoint(void) { unsigned int **task_bp_pinned; int cpu, err_cpu; @@ -641,7 +641,7 @@ static int __init init_hw_breakpoint(void) constraints_initialized = 1; - perf_pmu_register(&perf_breakpoint); + perf_pmu_register(&perf_breakpoint, "breakpoint", PERF_TYPE_BREAKPOINT); return register_die_notifier(&hw_breakpoint_exceptions_nb); @@ -655,6 +655,5 @@ static int __init init_hw_breakpoint(void) return -ENOMEM; } -core_initcall(init_hw_breakpoint); diff --git a/kernel/exit.c b/kernel/exit.c index b194febf579..8dd87418154 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -69,7 +69,7 @@ static void __unhash_process(struct task_struct *p, bool group_dead) list_del_rcu(&p->tasks); list_del_init(&p->sibling); - __get_cpu_var(process_counts)--; + __this_cpu_dec(process_counts); } list_del_rcu(&p->thread_group); } @@ -96,6 +96,14 @@ static void __exit_signal(struct task_struct *tsk) sig->tty = NULL; } else { /* + * This can only happen if the caller is de_thread(). + * FIXME: this is the temporary hack, we should teach + * posix-cpu-timers to handle this case correctly. + */ + if (unlikely(has_group_leader_pid(tsk))) + posix_cpu_timers_exit_group(tsk); + + /* * If there is any task waiting for the group exit * then notify it: */ @@ -833,7 +841,7 @@ static void exit_notify(struct task_struct *tsk, int group_dead) /* Let father know we died * * Thread signals are configurable, but you aren't going to use - * that to send signals to arbitary processes. + * that to send signals to arbitrary processes. * That stops right now. * * If the parent exec id doesn't match the exec id we saved @@ -900,12 +908,22 @@ NORET_TYPE void do_exit(long code) profile_task_exit(tsk); WARN_ON(atomic_read(&tsk->fs_excl)); + WARN_ON(blk_needs_flush_plug(tsk)); if (unlikely(in_interrupt())) panic("Aiee, killing interrupt handler!"); if (unlikely(!tsk->pid)) panic("Attempted to kill the idle task!"); + /* + * If do_exit is called because this processes oopsed, it's possible + * that get_fs() was left as KERNEL_DS, so reset it to USER_DS before + * continuing. Amongst other possible reasons, this is to prevent + * mm_release()->clear_child_tid() from writing to a user-controlled + * kernel address. + */ + set_fs(USER_DS); + tracehook_report_exit(&code); validate_creds_for_do_exit(tsk); @@ -977,6 +995,15 @@ NORET_TYPE void do_exit(long code) exit_fs(tsk); check_stack_usage(); exit_thread(); + + /* + * Flush inherited counters to the parent - before the parent + * gets woken up by child-exit notifications. + * + * because of cgroup mode, must be called before cgroup_exit() + */ + perf_event_exit_task(tsk); + cgroup_exit(tsk, 1); if (group_dead) @@ -989,12 +1016,7 @@ NORET_TYPE void do_exit(long code) /* * FIXME: do that only when needed, using sched_exit tracepoint */ - flush_ptrace_hw_breakpoint(tsk); - /* - * Flush inherited counters to the parent - before the parent - * gets woken up by child-exit notifications. - */ - perf_event_exit_task(tsk); + ptrace_put_breakpoints(tsk); exit_notify(tsk, group_dead); #ifdef CONFIG_NUMA diff --git a/kernel/extable.c b/kernel/extable.c index 7f8f263f852..5339705b824 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -72,6 +72,24 @@ int core_kernel_text(unsigned long addr) return 0; } +/** + * core_kernel_data - tell if addr points to kernel data + * @addr: address to test + * + * Returns true if @addr passed in is from the core kernel data + * section. + * + * Note: On some archs it may return true for core RODATA, and false + * for others. But will always be true for core RW data. + */ +int core_kernel_data(unsigned long addr) +{ + if (addr >= (unsigned long)_sdata && + addr < (unsigned long)_edata) + return 1; + return 0; +} + int __kernel_text_address(unsigned long addr) { if (core_kernel_text(addr)) diff --git a/kernel/fork.c b/kernel/fork.c index 3b159c5991b..2b44d82b823 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -40,6 +40,7 @@ #include <linux/tracehook.h> #include <linux/futex.h> #include <linux/compat.h> +#include <linux/kthread.h> #include <linux/task_io_accounting_ops.h> #include <linux/rcupdate.h> #include <linux/ptrace.h> @@ -66,6 +67,7 @@ #include <linux/posix-timers.h> #include <linux/user-return-notifier.h> #include <linux/oom.h> +#include <linux/khugepaged.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -108,20 +110,25 @@ int nr_processes(void) } #ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR -# define alloc_task_struct() kmem_cache_alloc(task_struct_cachep, GFP_KERNEL) -# define free_task_struct(tsk) kmem_cache_free(task_struct_cachep, (tsk)) +# define alloc_task_struct_node(node) \ + kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node) +# define free_task_struct(tsk) \ + kmem_cache_free(task_struct_cachep, (tsk)) static struct kmem_cache *task_struct_cachep; #endif #ifndef __HAVE_ARCH_THREAD_INFO_ALLOCATOR -static inline struct thread_info *alloc_thread_info(struct task_struct *tsk) +static struct thread_info *alloc_thread_info_node(struct task_struct *tsk, + int node) { #ifdef CONFIG_DEBUG_STACK_USAGE gfp_t mask = GFP_KERNEL | __GFP_ZERO; #else gfp_t mask = GFP_KERNEL; #endif - return (struct thread_info *)__get_free_pages(mask, THREAD_SIZE_ORDER); + struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER); + + return page ? page_address(page) : NULL; } static inline void free_thread_info(struct thread_info *ti) @@ -169,6 +176,7 @@ EXPORT_SYMBOL(free_task); static inline void free_signal_struct(struct signal_struct *sig) { taskstats_tgid_free(sig); + sched_autogroup_exit(sig); kmem_cache_free(signal_cachep, sig); } @@ -191,6 +199,7 @@ void __put_task_struct(struct task_struct *tsk) if (!profile_handoff_task(tsk)) free_task(tsk); } +EXPORT_SYMBOL_GPL(__put_task_struct); /* * macro override instead of weak attribute alias, to workaround @@ -246,16 +255,16 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) struct task_struct *tsk; struct thread_info *ti; unsigned long *stackend; - + int node = tsk_fork_get_node(orig); int err; prepare_to_copy(orig); - tsk = alloc_task_struct(); + tsk = alloc_task_struct_node(node); if (!tsk) return NULL; - ti = alloc_thread_info(tsk); + ti = alloc_thread_info_node(tsk, node); if (!ti) { free_task_struct(tsk); return NULL; @@ -273,6 +282,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) setup_thread_stack(tsk, orig); clear_user_return_notifier(tsk); + clear_tsk_need_resched(tsk); stackend = end_of_stack(tsk); *stackend = STACK_END_MAGIC; /* for overflow detection */ @@ -328,6 +338,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) retval = ksm_fork(mm, oldmm); if (retval) goto out; + retval = khugepaged_fork(mm, oldmm); + if (retval) + goto out; prev = NULL; for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { @@ -527,6 +540,9 @@ void __mmdrop(struct mm_struct *mm) mm_free_pgd(mm); destroy_context(mm); mmu_notifier_mm_destroy(mm); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + VM_BUG_ON(mm->pmd_huge_pte); +#endif free_mm(mm); } EXPORT_SYMBOL_GPL(__mmdrop); @@ -541,6 +557,7 @@ void mmput(struct mm_struct *mm) if (atomic_dec_and_test(&mm->mm_users)) { exit_aio(mm); ksm_exit(mm); + khugepaged_exit(mm); /* must run before exit_mmap */ exit_mmap(mm); set_mm_exe_file(mm, NULL); if (!list_empty(&mm->mmlist)) { @@ -667,6 +684,10 @@ struct mm_struct *dup_mm(struct task_struct *tsk) mm->token_priority = 0; mm->last_interval = 0; +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + mm->pmd_huge_pte = NULL; +#endif + if (!mm_init(mm, tsk)) goto fail_nomem; @@ -904,9 +925,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) posix_cpu_timers_init_group(sig); tty_audit_fork(sig); + sched_autogroup_fork(sig); sig->oom_adj = current->signal->oom_adj; sig->oom_score_adj = current->signal->oom_score_adj; + sig->oom_score_adj_min = current->signal->oom_score_adj_min; mutex_init(&sig->cred_guard_mutex); @@ -1080,7 +1103,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, posix_cpu_timers_init(p); - p->lock_depth = -1; /* -1 = no lock */ do_posix_clock_monotonic_gettime(&p->start_time); p->real_start_time = p->start_time; monotonic_to_bootbased(&p->real_start_time); @@ -1130,7 +1152,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #endif /* Perform scheduler related setup. Assign this task to a CPU. */ - sched_fork(p, clone_flags); + sched_fork(p); retval = perf_event_init_task(p); if (retval) @@ -1164,12 +1186,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, pid = alloc_pid(p->nsproxy->pid_ns); if (!pid) goto bad_fork_cleanup_io; - - if (clone_flags & CLONE_NEWPID) { - retval = pid_ns_prepare_proc(p->nsproxy->pid_ns); - if (retval < 0) - goto bad_fork_free_pid; - } } p->pid = pid_nr(pid); @@ -1188,6 +1204,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, * Clear TID on mm_release()? */ p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL; +#ifdef CONFIG_BLOCK + p->plug = NULL; +#endif #ifdef CONFIG_FUTEX p->robust_list = NULL; #ifdef CONFIG_COMPAT @@ -1273,7 +1292,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, tracehook_finish_clone(p, clone_flags, trace); if (thread_group_leader(p)) { - if (clone_flags & CLONE_NEWPID) + if (is_child_reaper(pid)) p->nsproxy->pid_ns->child_reaper = p; p->signal->leader_pid = pid; @@ -1282,7 +1301,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, attach_pid(p, PIDTYPE_SID, task_session(current)); list_add_tail(&p->sibling, &p->real_parent->children); list_add_tail_rcu(&p->tasks, &init_task.tasks); - __get_cpu_var(process_counts)++; + __this_cpu_inc(process_counts); } attach_pid(p, PIDTYPE_PID, pid); nr_threads++; @@ -1407,23 +1426,6 @@ long do_fork(unsigned long clone_flags, } /* - * We hope to recycle these flags after 2.6.26 - */ - if (unlikely(clone_flags & CLONE_STOPPED)) { - static int __read_mostly count = 100; - - if (count > 0 && printk_ratelimit()) { - char comm[TASK_COMM_LEN]; - - count--; - printk(KERN_INFO "fork(): process `%s' used deprecated " - "clone flags 0x%lx\n", - get_task_comm(comm, current), - clone_flags & CLONE_STOPPED); - } - } - - /* * When called from kernel_thread, don't do user tracing stuff. */ if (likely(user_mode(regs))) @@ -1461,16 +1463,7 @@ long do_fork(unsigned long clone_flags, */ p->flags &= ~PF_STARTING; - if (unlikely(clone_flags & CLONE_STOPPED)) { - /* - * We'll start up with an immediate SIGSTOP. - */ - sigaddset(&p->pending.signal, SIGSTOP); - set_tsk_thread_flag(p, TIF_SIGPENDING); - __set_task_state(p, TASK_STOPPED); - } else { - wake_up_new_task(p, clone_flags); - } + wake_up_new_task(p); tracehook_report_clone_complete(trace, regs, clone_flags, nr, p); @@ -1522,38 +1515,24 @@ void __init proc_caches_init(void) } /* - * Check constraints on flags passed to the unshare system call and - * force unsharing of additional process context as appropriate. + * Check constraints on flags passed to the unshare system call. */ -static void check_unshare_flags(unsigned long *flags_ptr) +static int check_unshare_flags(unsigned long unshare_flags) { + if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND| + CLONE_VM|CLONE_FILES|CLONE_SYSVSEM| + CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET)) + return -EINVAL; /* - * If unsharing a thread from a thread group, must also - * unshare vm. - */ - if (*flags_ptr & CLONE_THREAD) - *flags_ptr |= CLONE_VM; - - /* - * If unsharing vm, must also unshare signal handlers. - */ - if (*flags_ptr & CLONE_VM) - *flags_ptr |= CLONE_SIGHAND; - - /* - * If unsharing namespace, must also unshare filesystem information. + * Not implemented, but pretend it works if there is nothing to + * unshare. Note that unsharing CLONE_THREAD or CLONE_SIGHAND + * needs to unshare vm. */ - if (*flags_ptr & CLONE_NEWNS) - *flags_ptr |= CLONE_FS; -} - -/* - * Unsharing of tasks created with CLONE_THREAD is not supported yet - */ -static int unshare_thread(unsigned long unshare_flags) -{ - if (unshare_flags & CLONE_THREAD) - return -EINVAL; + if (unshare_flags & (CLONE_THREAD | CLONE_SIGHAND | CLONE_VM)) { + /* FIXME: get_task_mm() increments ->mm_users */ + if (atomic_read(¤t->mm->mm_users) > 1) + return -EINVAL; + } return 0; } @@ -1580,34 +1559,6 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp) } /* - * Unsharing of sighand is not supported yet - */ -static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct **new_sighp) -{ - struct sighand_struct *sigh = current->sighand; - - if ((unshare_flags & CLONE_SIGHAND) && atomic_read(&sigh->count) > 1) - return -EINVAL; - else - return 0; -} - -/* - * Unshare vm if it is being shared - */ -static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp) -{ - struct mm_struct *mm = current->mm; - - if ((unshare_flags & CLONE_VM) && - (mm && atomic_read(&mm->mm_users) > 1)) { - return -EINVAL; - } - - return 0; -} - -/* * Unshare file descriptor table if it is being shared */ static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp) @@ -1635,45 +1586,37 @@ static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp */ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags) { - int err = 0; struct fs_struct *fs, *new_fs = NULL; - struct sighand_struct *new_sigh = NULL; - struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL; struct files_struct *fd, *new_fd = NULL; struct nsproxy *new_nsproxy = NULL; int do_sysvsem = 0; + int err; - check_unshare_flags(&unshare_flags); - - /* Return -EINVAL for all unsupported flags */ - err = -EINVAL; - if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND| - CLONE_VM|CLONE_FILES|CLONE_SYSVSEM| - CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET)) + err = check_unshare_flags(unshare_flags); + if (err) goto bad_unshare_out; /* + * If unsharing namespace, must also unshare filesystem information. + */ + if (unshare_flags & CLONE_NEWNS) + unshare_flags |= CLONE_FS; + /* * CLONE_NEWIPC must also detach from the undolist: after switching * to a new ipc namespace, the semaphore arrays from the old * namespace are unreachable. */ if (unshare_flags & (CLONE_NEWIPC|CLONE_SYSVSEM)) do_sysvsem = 1; - if ((err = unshare_thread(unshare_flags))) - goto bad_unshare_out; if ((err = unshare_fs(unshare_flags, &new_fs))) - goto bad_unshare_cleanup_thread; - if ((err = unshare_sighand(unshare_flags, &new_sigh))) - goto bad_unshare_cleanup_fs; - if ((err = unshare_vm(unshare_flags, &new_mm))) - goto bad_unshare_cleanup_sigh; + goto bad_unshare_out; if ((err = unshare_fd(unshare_flags, &new_fd))) - goto bad_unshare_cleanup_vm; + goto bad_unshare_cleanup_fs; if ((err = unshare_nsproxy_namespaces(unshare_flags, &new_nsproxy, new_fs))) goto bad_unshare_cleanup_fd; - if (new_fs || new_mm || new_fd || do_sysvsem || new_nsproxy) { + if (new_fs || new_fd || do_sysvsem || new_nsproxy) { if (do_sysvsem) { /* * CLONE_SYSVSEM is equivalent to sys_exit(). @@ -1699,19 +1642,6 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags) spin_unlock(&fs->lock); } - if (new_mm) { - mm = current->mm; - active_mm = current->active_mm; - current->mm = new_mm; - current->active_mm = new_mm; - if (current->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) { - atomic_dec(&mm->oom_disable_count); - atomic_inc(&new_mm->oom_disable_count); - } - activate_mm(active_mm, new_mm); - new_mm = mm; - } - if (new_fd) { fd = current->files; current->files = new_fd; @@ -1728,20 +1658,10 @@ bad_unshare_cleanup_fd: if (new_fd) put_files_struct(new_fd); -bad_unshare_cleanup_vm: - if (new_mm) - mmput(new_mm); - -bad_unshare_cleanup_sigh: - if (new_sigh) - if (atomic_dec_and_test(&new_sigh->count)) - kmem_cache_free(sighand_cachep, new_sigh); - bad_unshare_cleanup_fs: if (new_fs) free_fs_struct(new_fs); -bad_unshare_cleanup_thread: bad_unshare_out: return err; } diff --git a/kernel/freezer.c b/kernel/freezer.c index bd1d42b17cb..7b01de98bb6 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -17,7 +17,7 @@ static inline void frozen_process(void) { if (!unlikely(current->flags & PF_NOFREEZE)) { current->flags |= PF_FROZEN; - wmb(); + smp_wmb(); } clear_freeze_flag(current); } @@ -93,7 +93,7 @@ bool freeze_task(struct task_struct *p, bool sig_only) * the task as frozen and next clears its TIF_FREEZE. */ if (!freezing(p)) { - rmb(); + smp_rmb(); if (frozen(p)) return false; @@ -104,8 +104,13 @@ bool freeze_task(struct task_struct *p, bool sig_only) } if (should_send_signal(p)) { - if (!signal_pending(p)) - fake_signal_wake_up(p); + fake_signal_wake_up(p); + /* + * fake_signal_wake_up() goes through p's scheduler + * lock and guarantees that TASK_STOPPED/TRACED -> + * TASK_RUNNING transition can't race with task state + * testing in try_to_freeze_tasks(). + */ } else if (sig_only) { return false; } else { diff --git a/kernel/futex.c b/kernel/futex.c index 6c683b37f2c..fe28dc282ea 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -69,6 +69,14 @@ int __read_mostly futex_cmpxchg_enabled; #define FUTEX_HASHBITS (CONFIG_BASE_SMALL ? 4 : 8) /* + * Futex flags used to encode options to functions and preserve them across + * restarts. + */ +#define FLAGS_SHARED 0x01 +#define FLAGS_CLOCKRT 0x02 +#define FLAGS_HAS_TIMEOUT 0x04 + +/* * Priority Inheritance state: */ struct futex_pi_state { @@ -123,6 +131,12 @@ struct futex_q { u32 bitset; }; +static const struct futex_q futex_q_init = { + /* list gets initialized in queue_me()*/ + .key = FUTEX_KEY_INIT, + .bitset = FUTEX_BITSET_MATCH_ANY +}; + /* * Hash buckets are shared by all the futex_keys that hash to the same * location. Each key may have multiple futex_q structures, one for each task @@ -219,7 +233,7 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key) { unsigned long address = (unsigned long)uaddr; struct mm_struct *mm = current->mm; - struct page *page; + struct page *page, *page_head; int err; /* @@ -251,11 +265,46 @@ again: if (err < 0) return err; - page = compound_head(page); - lock_page(page); - if (!page->mapping) { - unlock_page(page); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + page_head = page; + if (unlikely(PageTail(page))) { put_page(page); + /* serialize against __split_huge_page_splitting() */ + local_irq_disable(); + if (likely(__get_user_pages_fast(address, 1, 1, &page) == 1)) { + page_head = compound_head(page); + /* + * page_head is valid pointer but we must pin + * it before taking the PG_lock and/or + * PG_compound_lock. The moment we re-enable + * irqs __split_huge_page_splitting() can + * return and the head page can be freed from + * under us. We can't take the PG_lock and/or + * PG_compound_lock on a page that could be + * freed from under us. + */ + if (page != page_head) { + get_page(page_head); + put_page(page); + } + local_irq_enable(); + } else { + local_irq_enable(); + goto again; + } + } +#else + page_head = compound_head(page); + if (page != page_head) { + get_page(page_head); + put_page(page); + } +#endif + + lock_page(page_head); + if (!page_head->mapping) { + unlock_page(page_head); + put_page(page_head); goto again; } @@ -266,25 +315,24 @@ again: * it's a read-only handle, it's expected that futexes attach to * the object not the particular process. */ - if (PageAnon(page)) { + if (PageAnon(page_head)) { key->both.offset |= FUT_OFF_MMSHARED; /* ref taken on mm */ key->private.mm = mm; key->private.address = address; } else { key->both.offset |= FUT_OFF_INODE; /* inode-based key */ - key->shared.inode = page->mapping->host; - key->shared.pgoff = page->index; + key->shared.inode = page_head->mapping->host; + key->shared.pgoff = page_head->index; } get_futex_key_refs(key); - unlock_page(page); - put_page(page); + unlock_page(page_head); + put_page(page_head); return 0; } -static inline -void put_futex_key(int fshared, union futex_key *key) +static inline void put_futex_key(union futex_key *key) { drop_futex_key_refs(key); } @@ -333,15 +381,16 @@ static struct futex_q *futex_top_waiter(struct futex_hash_bucket *hb, return NULL; } -static u32 cmpxchg_futex_value_locked(u32 __user *uaddr, u32 uval, u32 newval) +static int cmpxchg_futex_value_locked(u32 *curval, u32 __user *uaddr, + u32 uval, u32 newval) { - u32 curval; + int ret; pagefault_disable(); - curval = futex_atomic_cmpxchg_inatomic(uaddr, uval, newval); + ret = futex_atomic_cmpxchg_inatomic(curval, uaddr, uval, newval); pagefault_enable(); - return curval; + return ret; } static int get_futex_value_locked(u32 *dest, u32 __user *from) @@ -626,7 +675,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb, struct task_struct *task, int set_waiters) { int lock_taken, ret, ownerdied = 0; - u32 uval, newval, curval; + u32 uval, newval, curval, vpid = task_pid_vnr(task); retry: ret = lock_taken = 0; @@ -636,19 +685,17 @@ retry: * (by doing a 0 -> TID atomic cmpxchg), while holding all * the locks. It will most likely not succeed. */ - newval = task_pid_vnr(task); + newval = vpid; if (set_waiters) newval |= FUTEX_WAITERS; - curval = cmpxchg_futex_value_locked(uaddr, 0, newval); - - if (unlikely(curval == -EFAULT)) + if (unlikely(cmpxchg_futex_value_locked(&curval, uaddr, 0, newval))) return -EFAULT; /* * Detect deadlocks. */ - if ((unlikely((curval & FUTEX_TID_MASK) == task_pid_vnr(task)))) + if ((unlikely((curval & FUTEX_TID_MASK) == vpid))) return -EDEADLK; /* @@ -675,14 +722,12 @@ retry: */ if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { /* Keep the OWNER_DIED bit */ - newval = (curval & ~FUTEX_TID_MASK) | task_pid_vnr(task); + newval = (curval & ~FUTEX_TID_MASK) | vpid; ownerdied = 0; lock_taken = 1; } - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (unlikely(curval == -EFAULT)) + if (unlikely(cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))) return -EFAULT; if (unlikely(curval != uval)) goto retry; @@ -727,6 +772,24 @@ retry: return ret; } +/** + * __unqueue_futex() - Remove the futex_q from its futex_hash_bucket + * @q: The futex_q to unqueue + * + * The q->lock_ptr must not be NULL and must be held by the caller. + */ +static void __unqueue_futex(struct futex_q *q) +{ + struct futex_hash_bucket *hb; + + if (WARN_ON_SMP(!q->lock_ptr || !spin_is_locked(q->lock_ptr)) + || WARN_ON(plist_node_empty(&q->list))) + return; + + hb = container_of(q->lock_ptr, struct futex_hash_bucket, lock); + plist_del(&q->list, &hb->chain); +} + /* * The hash bucket lock must be held when this is called. * Afterwards, the futex_q must not be accessed. @@ -744,7 +807,7 @@ static void wake_futex(struct futex_q *q) */ get_task_struct(p); - plist_del(&q->list, &q->list.plist); + __unqueue_futex(q); /* * The waiting task can free the futex_q as soon as * q->lock_ptr = NULL is written, without taking any locks. A @@ -778,10 +841,9 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this) new_owner = rt_mutex_next_owner(&pi_state->pi_mutex); /* - * This happens when we have stolen the lock and the original - * pending owner did not enqueue itself back on the rt_mutex. - * Thats not a tragedy. We know that way, that a lock waiter - * is on the fly. We make the futex_q waiter the pending owner. + * It is possible that the next waiter (the one that brought + * this owner to the kernel) timed out and is no longer + * waiting on the lock. */ if (!new_owner) new_owner = this->task; @@ -796,9 +858,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this) newval = FUTEX_WAITERS | task_pid_vnr(new_owner); - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) ret = -EFAULT; else if (curval != uval) ret = -EINVAL; @@ -833,10 +893,8 @@ static int unlock_futex_pi(u32 __user *uaddr, u32 uval) * There is no waiter, so we unlock the futex. The owner died * bit has not to be preserved here. We are the owner: */ - oldval = cmpxchg_futex_value_locked(uaddr, uval, 0); - - if (oldval == -EFAULT) - return oldval; + if (cmpxchg_futex_value_locked(&oldval, uaddr, uval, 0)) + return -EFAULT; if (oldval != uval) return -EAGAIN; @@ -870,7 +928,8 @@ double_unlock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2) /* * Wake up waiters matching bitset queued on this futex (uaddr). */ -static int futex_wake(u32 __user *uaddr, int fshared, int nr_wake, u32 bitset) +static int +futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) { struct futex_hash_bucket *hb; struct futex_q *this, *next; @@ -881,7 +940,7 @@ static int futex_wake(u32 __user *uaddr, int fshared, int nr_wake, u32 bitset) if (!bitset) return -EINVAL; - ret = get_futex_key(uaddr, fshared, &key); + ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key); if (unlikely(ret != 0)) goto out; @@ -907,7 +966,7 @@ static int futex_wake(u32 __user *uaddr, int fshared, int nr_wake, u32 bitset) } spin_unlock(&hb->lock); - put_futex_key(fshared, &key); + put_futex_key(&key); out: return ret; } @@ -917,7 +976,7 @@ out: * to this virtual address: */ static int -futex_wake_op(u32 __user *uaddr1, int fshared, u32 __user *uaddr2, +futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, int nr_wake, int nr_wake2, int op) { union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT; @@ -927,10 +986,10 @@ futex_wake_op(u32 __user *uaddr1, int fshared, u32 __user *uaddr2, int ret, op_ret; retry: - ret = get_futex_key(uaddr1, fshared, &key1); + ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1); if (unlikely(ret != 0)) goto out; - ret = get_futex_key(uaddr2, fshared, &key2); + ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2); if (unlikely(ret != 0)) goto out_put_key1; @@ -962,11 +1021,11 @@ retry_private: if (ret) goto out_put_keys; - if (!fshared) + if (!(flags & FLAGS_SHARED)) goto retry_private; - put_futex_key(fshared, &key2); - put_futex_key(fshared, &key1); + put_futex_key(&key2); + put_futex_key(&key1); goto retry; } @@ -996,9 +1055,9 @@ retry_private: double_unlock_hb(hb1, hb2); out_put_keys: - put_futex_key(fshared, &key2); + put_futex_key(&key2); out_put_key1: - put_futex_key(fshared, &key1); + put_futex_key(&key1); out: return ret; } @@ -1023,9 +1082,6 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1, plist_del(&q->list, &hb1->chain); plist_add(&q->list, &hb2->chain); q->lock_ptr = &hb2->lock; -#ifdef CONFIG_DEBUG_PI_LIST - q->list.plist.spinlock = &hb2->lock; -#endif } get_futex_key_refs(key2); q->key = *key2; @@ -1052,16 +1108,12 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key, get_futex_key_refs(key); q->key = *key; - WARN_ON(plist_node_empty(&q->list)); - plist_del(&q->list, &q->list.plist); + __unqueue_futex(q); WARN_ON(!q->rt_waiter); q->rt_waiter = NULL; q->lock_ptr = &hb->lock; -#ifdef CONFIG_DEBUG_PI_LIST - q->list.plist.spinlock = &hb->lock; -#endif wake_up_state(q->task, TASK_NORMAL); } @@ -1133,13 +1185,13 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex, /** * futex_requeue() - Requeue waiters from uaddr1 to uaddr2 * @uaddr1: source futex user address - * @fshared: 0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED + * @flags: futex flags (FLAGS_SHARED, etc.) * @uaddr2: target futex user address * @nr_wake: number of waiters to wake (must be 1 for requeue_pi) * @nr_requeue: number of waiters to requeue (0-INT_MAX) * @cmpval: @uaddr1 expected value (or %NULL) * @requeue_pi: if we are attempting to requeue from a non-pi futex to a - * pi futex (pi to pi requeue is not supported) + * pi futex (pi to pi requeue is not supported) * * Requeue waiters on uaddr1 to uaddr2. In the requeue_pi case, try to acquire * uaddr2 atomically on behalf of the top waiter. @@ -1148,9 +1200,9 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex, * >=0 - on success, the number of tasks requeued or woken * <0 - on error */ -static int futex_requeue(u32 __user *uaddr1, int fshared, u32 __user *uaddr2, - int nr_wake, int nr_requeue, u32 *cmpval, - int requeue_pi) +static int futex_requeue(u32 __user *uaddr1, unsigned int flags, + u32 __user *uaddr2, int nr_wake, int nr_requeue, + u32 *cmpval, int requeue_pi) { union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT; int drop_count = 0, task_count = 0, ret; @@ -1191,10 +1243,10 @@ retry: pi_state = NULL; } - ret = get_futex_key(uaddr1, fshared, &key1); + ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1); if (unlikely(ret != 0)) goto out; - ret = get_futex_key(uaddr2, fshared, &key2); + ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2); if (unlikely(ret != 0)) goto out_put_key1; @@ -1216,11 +1268,11 @@ retry_private: if (ret) goto out_put_keys; - if (!fshared) + if (!(flags & FLAGS_SHARED)) goto retry_private; - put_futex_key(fshared, &key2); - put_futex_key(fshared, &key1); + put_futex_key(&key2); + put_futex_key(&key1); goto retry; } if (curval != *cmpval) { @@ -1260,8 +1312,8 @@ retry_private: break; case -EFAULT: double_unlock_hb(hb1, hb2); - put_futex_key(fshared, &key2); - put_futex_key(fshared, &key1); + put_futex_key(&key2); + put_futex_key(&key1); ret = fault_in_user_writeable(uaddr2); if (!ret) goto retry; @@ -1269,8 +1321,8 @@ retry_private: case -EAGAIN: /* The owner was exiting, try again. */ double_unlock_hb(hb1, hb2); - put_futex_key(fshared, &key2); - put_futex_key(fshared, &key1); + put_futex_key(&key2); + put_futex_key(&key1); cond_resched(); goto retry; default: @@ -1352,9 +1404,9 @@ out_unlock: drop_futex_key_refs(&key1); out_put_keys: - put_futex_key(fshared, &key2); + put_futex_key(&key2); out_put_key1: - put_futex_key(fshared, &key1); + put_futex_key(&key1); out: if (pi_state != NULL) free_pi_state(pi_state); @@ -1409,9 +1461,6 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb) prio = min(current->normal_prio, MAX_RT_PRIO); plist_node_init(&q->list, prio); -#ifdef CONFIG_DEBUG_PI_LIST - q->list.plist.spinlock = &hb->lock; -#endif plist_add(&q->list, &hb->chain); q->task = current; spin_unlock(&hb->lock); @@ -1456,8 +1505,7 @@ retry: spin_unlock(lock_ptr); goto retry; } - WARN_ON(plist_node_empty(&q->list)); - plist_del(&q->list, &q->list.plist); + __unqueue_futex(q); BUG_ON(q->pi_state); @@ -1477,8 +1525,7 @@ retry: static void unqueue_me_pi(struct futex_q *q) __releases(q->lock_ptr) { - WARN_ON(plist_node_empty(&q->list)); - plist_del(&q->list, &q->list.plist); + __unqueue_futex(q); BUG_ON(!q->pi_state); free_pi_state(q->pi_state); @@ -1494,7 +1541,7 @@ static void unqueue_me_pi(struct futex_q *q) * private futexes. */ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, - struct task_struct *newowner, int fshared) + struct task_struct *newowner) { u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS; struct futex_pi_state *pi_state = q->pi_state; @@ -1508,10 +1555,10 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, /* * We are here either because we stole the rtmutex from the - * pending owner or we are the pending owner which failed to - * get the rtmutex. We have to replace the pending owner TID - * in the user space variable. This must be atomic as we have - * to preserve the owner died bit here. + * previous highest priority waiter or we are the highest priority + * waiter but failed to get the rtmutex the first time. + * We have to replace the newowner TID in the user space variable. + * This must be atomic as we have to preserve the owner died bit here. * * Note: We write the user space value _before_ changing the pi_state * because we can fault here. Imagine swapped out pages or a fork @@ -1530,9 +1577,7 @@ retry: while (1) { newval = (uval & FUTEX_OWNER_DIED) | newtid; - curval = cmpxchg_futex_value_locked(uaddr, uval, newval); - - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) goto handle_fault; if (curval == uval) break; @@ -1560,8 +1605,8 @@ retry: /* * To handle the page fault we need to drop the hash bucket - * lock here. That gives the other task (either the pending - * owner itself or the task which stole the rtmutex) the + * lock here. That gives the other task (either the highest priority + * waiter itself or the task which stole the rtmutex) the * chance to try the fixup of the pi_state. So once we are * back from handling the fault we need to check the pi_state * after reacquiring the hash bucket lock and before trying to @@ -1587,20 +1632,11 @@ handle_fault: goto retry; } -/* - * In case we must use restart_block to restart a futex_wait, - * we encode in the 'flags' shared capability - */ -#define FLAGS_SHARED 0x01 -#define FLAGS_CLOCKRT 0x02 -#define FLAGS_HAS_TIMEOUT 0x04 - static long futex_wait_restart(struct restart_block *restart); /** * fixup_owner() - Post lock pi_state and corner case management * @uaddr: user address of the futex - * @fshared: whether the futex is shared (1) or not (0) * @q: futex_q (contains pi_state and access to the rt_mutex) * @locked: if the attempt to take the rt_mutex succeeded (1) or not (0) * @@ -1613,8 +1649,7 @@ static long futex_wait_restart(struct restart_block *restart); * 0 - success, lock not taken * <0 - on error (-EFAULT) */ -static int fixup_owner(u32 __user *uaddr, int fshared, struct futex_q *q, - int locked) +static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked) { struct task_struct *owner; int ret = 0; @@ -1625,7 +1660,7 @@ static int fixup_owner(u32 __user *uaddr, int fshared, struct futex_q *q, * did a lock-steal - fix up the PI-state in that case: */ if (q->pi_state->owner != current) - ret = fixup_pi_state_owner(uaddr, q, current, fshared); + ret = fixup_pi_state_owner(uaddr, q, current); goto out; } @@ -1647,18 +1682,20 @@ static int fixup_owner(u32 __user *uaddr, int fshared, struct futex_q *q, /* * pi_state is incorrect, some other task did a lock steal and * we returned due to timeout or signal without taking the - * rt_mutex. Too late. We can access the rt_mutex_owner without - * locking, as the other task is now blocked on the hash bucket - * lock. Fix the state up. + * rt_mutex. Too late. */ + raw_spin_lock(&q->pi_state->pi_mutex.wait_lock); owner = rt_mutex_owner(&q->pi_state->pi_mutex); - ret = fixup_pi_state_owner(uaddr, q, owner, fshared); + if (!owner) + owner = rt_mutex_next_owner(&q->pi_state->pi_mutex); + raw_spin_unlock(&q->pi_state->pi_mutex.wait_lock); + ret = fixup_pi_state_owner(uaddr, q, owner); goto out; } /* * Paranoia check. If we did not take the lock, then we should not be - * the owner, nor the pending owner, of the rt_mutex. + * the owner of the rt_mutex. */ if (rt_mutex_owner(&q->pi_state->pi_mutex) == current) printk(KERN_ERR "fixup_owner: ret = %d pi-mutex: %p " @@ -1715,7 +1752,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q, * futex_wait_setup() - Prepare to wait on a futex * @uaddr: the futex userspace address * @val: the expected value - * @fshared: whether the futex is shared (1) or not (0) + * @flags: futex flags (FLAGS_SHARED, etc.) * @q: the associated futex_q * @hb: storage for hash_bucket pointer to be returned to caller * @@ -1728,7 +1765,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q, * 0 - uaddr contains val and hb has been locked * <1 - -EFAULT or -EWOULDBLOCK (uaddr does not contain val) and hb is unlcoked */ -static int futex_wait_setup(u32 __user *uaddr, u32 val, int fshared, +static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags, struct futex_q *q, struct futex_hash_bucket **hb) { u32 uval; @@ -1743,17 +1780,17 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, int fshared, * * The basic logical guarantee of a futex is that it blocks ONLY * if cond(var) is known to be true at the time of blocking, for - * any cond. If we queued after testing *uaddr, that would open - * a race condition where we could block indefinitely with + * any cond. If we locked the hash-bucket after testing *uaddr, that + * would open a race condition where we could block indefinitely with * cond(var) false, which would violate the guarantee. * - * A consequence is that futex_wait() can return zero and absorb - * a wakeup when *uaddr != val on entry to the syscall. This is - * rare, but normal. + * On the other hand, we insert q and release the hash-bucket only + * after testing *uaddr. This guarantees that futex_wait() will NOT + * absorb a wakeup if *uaddr does not match the desired values + * while the syscall executes. */ retry: - q->key = FUTEX_KEY_INIT; - ret = get_futex_key(uaddr, fshared, &q->key); + ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q->key); if (unlikely(ret != 0)) return ret; @@ -1769,10 +1806,10 @@ retry_private: if (ret) goto out; - if (!fshared) + if (!(flags & FLAGS_SHARED)) goto retry_private; - put_futex_key(fshared, &q->key); + put_futex_key(&q->key); goto retry; } @@ -1783,32 +1820,29 @@ retry_private: out: if (ret) - put_futex_key(fshared, &q->key); + put_futex_key(&q->key); return ret; } -static int futex_wait(u32 __user *uaddr, int fshared, - u32 val, ktime_t *abs_time, u32 bitset, int clockrt) +static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, + ktime_t *abs_time, u32 bitset) { struct hrtimer_sleeper timeout, *to = NULL; struct restart_block *restart; struct futex_hash_bucket *hb; - struct futex_q q; + struct futex_q q = futex_q_init; int ret; if (!bitset) return -EINVAL; - - q.pi_state = NULL; q.bitset = bitset; - q.rt_waiter = NULL; - q.requeue_pi_key = NULL; if (abs_time) { to = &timeout; - hrtimer_init_on_stack(&to->timer, clockrt ? CLOCK_REALTIME : - CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ? + CLOCK_REALTIME : CLOCK_MONOTONIC, + HRTIMER_MODE_ABS); hrtimer_init_sleeper(to, current); hrtimer_set_expires_range_ns(&to->timer, *abs_time, current->timer_slack_ns); @@ -1819,7 +1853,7 @@ retry: * Prepare to wait on uaddr. On success, holds hb lock and increments * q.key refs. */ - ret = futex_wait_setup(uaddr, val, fshared, &q, &hb); + ret = futex_wait_setup(uaddr, val, flags, &q, &hb); if (ret) goto out; @@ -1852,12 +1886,7 @@ retry: restart->futex.val = val; restart->futex.time = abs_time->tv64; restart->futex.bitset = bitset; - restart->futex.flags = FLAGS_HAS_TIMEOUT; - - if (fshared) - restart->futex.flags |= FLAGS_SHARED; - if (clockrt) - restart->futex.flags |= FLAGS_CLOCKRT; + restart->futex.flags = flags | FLAGS_HAS_TIMEOUT; ret = -ERESTART_RESTARTBLOCK; @@ -1873,7 +1902,6 @@ out: static long futex_wait_restart(struct restart_block *restart) { u32 __user *uaddr = restart->futex.uaddr; - int fshared = 0; ktime_t t, *tp = NULL; if (restart->futex.flags & FLAGS_HAS_TIMEOUT) { @@ -1881,11 +1909,9 @@ static long futex_wait_restart(struct restart_block *restart) tp = &t; } restart->fn = do_no_restart_syscall; - if (restart->futex.flags & FLAGS_SHARED) - fshared = 1; - return (long)futex_wait(uaddr, fshared, restart->futex.val, tp, - restart->futex.bitset, - restart->futex.flags & FLAGS_CLOCKRT); + + return (long)futex_wait(uaddr, restart->futex.flags, + restart->futex.val, tp, restart->futex.bitset); } @@ -1895,12 +1921,12 @@ static long futex_wait_restart(struct restart_block *restart) * if there are waiters then it will block, it does PI, etc. (Due to * races the kernel might see a 0 value of the futex too.) */ -static int futex_lock_pi(u32 __user *uaddr, int fshared, - int detect, ktime_t *time, int trylock) +static int futex_lock_pi(u32 __user *uaddr, unsigned int flags, int detect, + ktime_t *time, int trylock) { struct hrtimer_sleeper timeout, *to = NULL; struct futex_hash_bucket *hb; - struct futex_q q; + struct futex_q q = futex_q_init; int res, ret; if (refill_pi_state_cache()) @@ -1914,12 +1940,8 @@ static int futex_lock_pi(u32 __user *uaddr, int fshared, hrtimer_set_expires(&to->timer, *time); } - q.pi_state = NULL; - q.rt_waiter = NULL; - q.requeue_pi_key = NULL; retry: - q.key = FUTEX_KEY_INIT; - ret = get_futex_key(uaddr, fshared, &q.key); + ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q.key); if (unlikely(ret != 0)) goto out; @@ -1941,7 +1963,7 @@ retry_private: * exit to complete. */ queue_unlock(&q, hb); - put_futex_key(fshared, &q.key); + put_futex_key(&q.key); cond_resched(); goto retry; default: @@ -1971,7 +1993,7 @@ retry_private: * Fixup the pi_state owner and possibly acquire the lock if we * haven't already. */ - res = fixup_owner(uaddr, fshared, &q, !ret); + res = fixup_owner(uaddr, &q, !ret); /* * If fixup_owner() returned an error, proprogate that. If it acquired * the lock, clear our -ETIMEDOUT or -EINTR. @@ -1995,7 +2017,7 @@ out_unlock_put_key: queue_unlock(&q, hb); out_put_key: - put_futex_key(fshared, &q.key); + put_futex_key(&q.key); out: if (to) destroy_hrtimer_on_stack(&to->timer); @@ -2008,10 +2030,10 @@ uaddr_faulted: if (ret) goto out_put_key; - if (!fshared) + if (!(flags & FLAGS_SHARED)) goto retry_private; - put_futex_key(fshared, &q.key); + put_futex_key(&q.key); goto retry; } @@ -2020,13 +2042,13 @@ uaddr_faulted: * This is the in-kernel slowpath: we look up the PI state (if any), * and do the rt-mutex unlock. */ -static int futex_unlock_pi(u32 __user *uaddr, int fshared) +static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags) { struct futex_hash_bucket *hb; struct futex_q *this, *next; - u32 uval; struct plist_head *head; union futex_key key = FUTEX_KEY_INIT; + u32 uval, vpid = task_pid_vnr(current); int ret; retry: @@ -2035,10 +2057,10 @@ retry: /* * We release only a lock we actually own: */ - if ((uval & FUTEX_TID_MASK) != task_pid_vnr(current)) + if ((uval & FUTEX_TID_MASK) != vpid) return -EPERM; - ret = get_futex_key(uaddr, fshared, &key); + ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key); if (unlikely(ret != 0)) goto out; @@ -2050,17 +2072,14 @@ retry: * again. If it succeeds then we can return without waking * anyone else up: */ - if (!(uval & FUTEX_OWNER_DIED)) - uval = cmpxchg_futex_value_locked(uaddr, task_pid_vnr(current), 0); - - - if (unlikely(uval == -EFAULT)) + if (!(uval & FUTEX_OWNER_DIED) && + cmpxchg_futex_value_locked(&uval, uaddr, vpid, 0)) goto pi_faulted; /* * Rare case: we managed to release the lock atomically, * no need to wake anyone else up: */ - if (unlikely(uval == task_pid_vnr(current))) + if (unlikely(uval == vpid)) goto out_unlock; /* @@ -2093,14 +2112,14 @@ retry: out_unlock: spin_unlock(&hb->lock); - put_futex_key(fshared, &key); + put_futex_key(&key); out: return ret; pi_faulted: spin_unlock(&hb->lock); - put_futex_key(fshared, &key); + put_futex_key(&key); ret = fault_in_user_writeable(uaddr); if (!ret) @@ -2145,7 +2164,7 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb, * We were woken prior to requeue by a timeout or a signal. * Unqueue the futex_q and determine which it was. */ - plist_del(&q->list, &q->list.plist); + plist_del(&q->list, &hb->chain); /* Handle spurious wakeups gracefully */ ret = -EWOULDBLOCK; @@ -2160,7 +2179,7 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb, /** * futex_wait_requeue_pi() - Wait on uaddr and take uaddr2 * @uaddr: the futex we initially wait on (non-pi) - * @fshared: whether the futexes are shared (1) or not (0). They must be + * @flags: futex flags (FLAGS_SHARED, FLAGS_CLOCKRT, etc.), they must be * the same type, no requeueing from private to shared, etc. * @val: the expected value of uaddr * @abs_time: absolute timeout @@ -2198,16 +2217,16 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb, * 0 - On success * <0 - On error */ -static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, +static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset, - int clockrt, u32 __user *uaddr2) + u32 __user *uaddr2) { struct hrtimer_sleeper timeout, *to = NULL; struct rt_mutex_waiter rt_waiter; struct rt_mutex *pi_mutex = NULL; struct futex_hash_bucket *hb; - union futex_key key2; - struct futex_q q; + union futex_key key2 = FUTEX_KEY_INIT; + struct futex_q q = futex_q_init; int res, ret; if (!bitset) @@ -2215,8 +2234,9 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, if (abs_time) { to = &timeout; - hrtimer_init_on_stack(&to->timer, clockrt ? CLOCK_REALTIME : - CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ? + CLOCK_REALTIME : CLOCK_MONOTONIC, + HRTIMER_MODE_ABS); hrtimer_init_sleeper(to, current); hrtimer_set_expires_range_ns(&to->timer, *abs_time, current->timer_slack_ns); @@ -2229,12 +2249,10 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, debug_rt_mutex_init_waiter(&rt_waiter); rt_waiter.task = NULL; - key2 = FUTEX_KEY_INIT; - ret = get_futex_key(uaddr2, fshared, &key2); + ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2); if (unlikely(ret != 0)) goto out; - q.pi_state = NULL; q.bitset = bitset; q.rt_waiter = &rt_waiter; q.requeue_pi_key = &key2; @@ -2243,7 +2261,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, * Prepare to wait on uaddr. On success, increments q.key (key1) ref * count. */ - ret = futex_wait_setup(uaddr, val, fshared, &q, &hb); + ret = futex_wait_setup(uaddr, val, flags, &q, &hb); if (ret) goto out_key2; @@ -2273,8 +2291,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, */ if (q.pi_state && (q.pi_state->owner != current)) { spin_lock(q.lock_ptr); - ret = fixup_pi_state_owner(uaddr2, &q, current, - fshared); + ret = fixup_pi_state_owner(uaddr2, &q, current); spin_unlock(q.lock_ptr); } } else { @@ -2293,7 +2310,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, * Fixup the pi_state owner and possibly acquire the lock if we * haven't already. */ - res = fixup_owner(uaddr2, fshared, &q, !ret); + res = fixup_owner(uaddr2, &q, !ret); /* * If fixup_owner() returned an error, proprogate that. If it * acquired the lock, clear -ETIMEDOUT or -EINTR. @@ -2324,9 +2341,9 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared, } out_put_keys: - put_futex_key(fshared, &q.key); + put_futex_key(&q.key); out_key2: - put_futex_key(fshared, &key2); + put_futex_key(&key2); out: if (to) { @@ -2401,10 +2418,19 @@ SYSCALL_DEFINE3(get_robust_list, int, pid, goto err_unlock; ret = -EPERM; pcred = __task_cred(p); + /* If victim is in different user_ns, then uids are not + comparable, so we must have CAP_SYS_PTRACE */ + if (cred->user->user_ns != pcred->user->user_ns) { + if (!ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE)) + goto err_unlock; + goto ok; + } + /* If victim is in same user_ns, then uids are comparable */ if (cred->euid != pcred->euid && cred->euid != pcred->uid && - !capable(CAP_SYS_PTRACE)) + !ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE)) goto err_unlock; +ok: head = p->robust_list; rcu_read_unlock(); } @@ -2443,11 +2469,20 @@ retry: * userspace. */ mval = (uval & FUTEX_WAITERS) | FUTEX_OWNER_DIED; - nval = futex_atomic_cmpxchg_inatomic(uaddr, uval, mval); - - if (nval == -EFAULT) - return -1; - + /* + * We are not holding a lock here, but we want to have + * the pagefault_disable/enable() protection because + * we want to handle the fault gracefully. If the + * access fails we try to fault in the futex with R/W + * verification via get_user_pages. get_user() above + * does not guarantee R/W access. If that fails we + * give up and leave the futex locked. + */ + if (cmpxchg_futex_value_locked(&nval, uaddr, uval, mval)) { + if (fault_in_user_writeable(uaddr)) + return -1; + goto retry; + } if (nval != uval) goto retry; @@ -2489,7 +2524,8 @@ void exit_robust_list(struct task_struct *curr) { struct robust_list_head __user *head = curr->robust_list; struct robust_list __user *entry, *next_entry, *pending; - unsigned int limit = ROBUST_LIST_LIMIT, pi, next_pi, pip; + unsigned int limit = ROBUST_LIST_LIMIT, pi, pip; + unsigned int uninitialized_var(next_pi); unsigned long futex_offset; int rc; @@ -2550,58 +2586,57 @@ void exit_robust_list(struct task_struct *curr) long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, u32 __user *uaddr2, u32 val2, u32 val3) { - int clockrt, ret = -ENOSYS; - int cmd = op & FUTEX_CMD_MASK; - int fshared = 0; + int ret = -ENOSYS, cmd = op & FUTEX_CMD_MASK; + unsigned int flags = 0; if (!(op & FUTEX_PRIVATE_FLAG)) - fshared = 1; + flags |= FLAGS_SHARED; - clockrt = op & FUTEX_CLOCK_REALTIME; - if (clockrt && cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI) - return -ENOSYS; + if (op & FUTEX_CLOCK_REALTIME) { + flags |= FLAGS_CLOCKRT; + if (cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI) + return -ENOSYS; + } switch (cmd) { case FUTEX_WAIT: val3 = FUTEX_BITSET_MATCH_ANY; case FUTEX_WAIT_BITSET: - ret = futex_wait(uaddr, fshared, val, timeout, val3, clockrt); + ret = futex_wait(uaddr, flags, val, timeout, val3); break; case FUTEX_WAKE: val3 = FUTEX_BITSET_MATCH_ANY; case FUTEX_WAKE_BITSET: - ret = futex_wake(uaddr, fshared, val, val3); + ret = futex_wake(uaddr, flags, val, val3); break; case FUTEX_REQUEUE: - ret = futex_requeue(uaddr, fshared, uaddr2, val, val2, NULL, 0); + ret = futex_requeue(uaddr, flags, uaddr2, val, val2, NULL, 0); break; case FUTEX_CMP_REQUEUE: - ret = futex_requeue(uaddr, fshared, uaddr2, val, val2, &val3, - 0); + ret = futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 0); break; case FUTEX_WAKE_OP: - ret = futex_wake_op(uaddr, fshared, uaddr2, val, val2, val3); + ret = futex_wake_op(uaddr, flags, uaddr2, val, val2, val3); break; case FUTEX_LOCK_PI: if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, fshared, val, timeout, 0); + ret = futex_lock_pi(uaddr, flags, val, timeout, 0); break; case FUTEX_UNLOCK_PI: if (futex_cmpxchg_enabled) - ret = futex_unlock_pi(uaddr, fshared); + ret = futex_unlock_pi(uaddr, flags); break; case FUTEX_TRYLOCK_PI: if (futex_cmpxchg_enabled) - ret = futex_lock_pi(uaddr, fshared, 0, timeout, 1); + ret = futex_lock_pi(uaddr, flags, 0, timeout, 1); break; case FUTEX_WAIT_REQUEUE_PI: val3 = FUTEX_BITSET_MATCH_ANY; - ret = futex_wait_requeue_pi(uaddr, fshared, val, timeout, val3, - clockrt, uaddr2); + ret = futex_wait_requeue_pi(uaddr, flags, val, timeout, val3, + uaddr2); break; case FUTEX_CMP_REQUEUE_PI: - ret = futex_requeue(uaddr, fshared, uaddr2, val, val2, &val3, - 1); + ret = futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 1); break; default: ret = -ENOSYS; @@ -2658,8 +2693,7 @@ static int __init futex_init(void) * implementation, the non-functional ones will return * -ENOSYS. */ - curval = cmpxchg_futex_value_locked(NULL, 0, 0); - if (curval == -EFAULT) + if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT) futex_cmpxchg_enabled = 1; for (i = 0; i < ARRAY_SIZE(futex_queues); i++) { diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c index 06da4dfc339..5f9e689dc8f 100644 --- a/kernel/futex_compat.c +++ b/kernel/futex_compat.c @@ -49,7 +49,8 @@ void compat_exit_robust_list(struct task_struct *curr) { struct compat_robust_list_head __user *head = curr->compat_robust_list; struct robust_list __user *entry, *next_entry, *pending; - unsigned int limit = ROBUST_LIST_LIMIT, pi, next_pi, pip; + unsigned int limit = ROBUST_LIST_LIMIT, pi, pip; + unsigned int uninitialized_var(next_pi); compat_uptr_t uentry, next_uentry, upending; compat_long_t futex_offset; int rc; @@ -152,10 +153,19 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr, goto err_unlock; ret = -EPERM; pcred = __task_cred(p); + /* If victim is in different user_ns, then uids are not + comparable, so we must have CAP_SYS_PTRACE */ + if (cred->user->user_ns != pcred->user->user_ns) { + if (!ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE)) + goto err_unlock; + goto ok; + } + /* If victim is in same user_ns, then uids are comparable */ if (cred->euid != pcred->euid && cred->euid != pcred->uid && - !capable(CAP_SYS_PTRACE)) + !ns_capable(pcred->user->user_ns, CAP_SYS_PTRACE)) goto err_unlock; +ok: head = p->compat_robust_list; rcu_read_unlock(); } diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig index 70a298d6da7..b8cadf70b1f 100644 --- a/kernel/gcov/Kconfig +++ b/kernel/gcov/Kconfig @@ -34,7 +34,7 @@ config GCOV_KERNEL config GCOV_PROFILE_ALL bool "Profile entire Kernel" depends on GCOV_KERNEL - depends on S390 || X86 || (PPC && EXPERIMENTAL) || MICROBLAZE + depends on SUPERH || S390 || X86 || (PPC && EXPERIMENTAL) || MICROBLAZE default n ---help--- This options activates profiling for the entire kernel. diff --git a/kernel/gcov/Makefile b/kernel/gcov/Makefile index 3f761001d51..e97ca59e252 100644 --- a/kernel/gcov/Makefile +++ b/kernel/gcov/Makefile @@ -1,3 +1,3 @@ -EXTRA_CFLAGS := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"' +ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"' obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o gcc_3_4.o diff --git a/kernel/groups.c b/kernel/groups.c index 253dc0f35cf..1cc476d52dd 100644 --- a/kernel/groups.c +++ b/kernel/groups.c @@ -233,7 +233,7 @@ SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist) struct group_info *group_info; int retval; - if (!capable(CAP_SETGID)) + if (!nsown_capable(CAP_SETGID)) return -EPERM; if ((unsigned)gidsetsize > NGROUPS_MAX) return -EINVAL; diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 72206cf5c6c..dbbbf7d4308 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -53,11 +53,10 @@ /* * The timer bases: * - * Note: If we want to add new timer bases, we have to skip the two - * clock ids captured by the cpu-timers. We do this by holding empty - * entries rather than doing math adjustment of the clock ids. - * This ensures that we capture erroneous accesses to these clock ids - * rather than moving them into the range of valid clock id's. + * There are more clockids then hrtimer bases. Thus, we index + * into the timer bases by the hrtimer_base_type enum. When trying + * to reach a base using a clockid, hrtimer_clockid_to_base() + * is used to convert from clockid to the proper hrtimer_base_type. */ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = { @@ -74,30 +73,43 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = .get_time = &ktime_get, .resolution = KTIME_LOW_RES, }, + { + .index = CLOCK_BOOTTIME, + .get_time = &ktime_get_boottime, + .resolution = KTIME_LOW_RES, + }, } }; +static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = { + [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME, + [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC, + [CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME, +}; + +static inline int hrtimer_clockid_to_base(clockid_t clock_id) +{ + return hrtimer_clock_to_base_table[clock_id]; +} + + /* * Get the coarse grained time at the softirq based on xtime and * wall_to_monotonic. */ static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base) { - ktime_t xtim, tomono; - struct timespec xts, tom; - unsigned long seq; + ktime_t xtim, mono, boot; + struct timespec xts, tom, slp; - do { - seq = read_seqbegin(&xtime_lock); - xts = __current_kernel_time(); - tom = __get_wall_to_monotonic(); - } while (read_seqretry(&xtime_lock, seq)); + get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp); xtim = timespec_to_ktime(xts); - tomono = timespec_to_ktime(tom); - base->clock_base[CLOCK_REALTIME].softirq_time = xtim; - base->clock_base[CLOCK_MONOTONIC].softirq_time = - ktime_add(xtim, tomono); + mono = ktime_add(xtim, timespec_to_ktime(tom)); + boot = ktime_add(mono, timespec_to_ktime(slp)); + base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim; + base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono; + base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot; } /* @@ -184,10 +196,11 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base, struct hrtimer_cpu_base *new_cpu_base; int this_cpu = smp_processor_id(); int cpu = hrtimer_get_target(this_cpu, pinned); + int basenum = hrtimer_clockid_to_base(base->index); again: new_cpu_base = &per_cpu(hrtimer_bases, cpu); - new_base = &new_cpu_base->clock_base[base->index]; + new_base = &new_cpu_base->clock_base[basenum]; if (base != new_base) { /* @@ -334,6 +347,11 @@ EXPORT_SYMBOL_GPL(ktime_add_safe); static struct debug_obj_descr hrtimer_debug_descr; +static void *hrtimer_debug_hint(void *addr) +{ + return ((struct hrtimer *) addr)->function; +} + /* * fixup_init is called when: * - an active object is initialized @@ -393,6 +411,7 @@ static int hrtimer_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr hrtimer_debug_descr = { .name = "hrtimer", + .debug_hint = hrtimer_debug_hint, .fixup_init = hrtimer_fixup_init, .fixup_activate = hrtimer_fixup_activate, .fixup_free = hrtimer_fixup_free, @@ -497,7 +516,7 @@ static inline int hrtimer_is_hres_enabled(void) */ static inline int hrtimer_hres_active(void) { - return __get_cpu_var(hrtimer_bases).hres_active; + return __this_cpu_read(hrtimer_bases.hres_active); } /* @@ -516,10 +535,13 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal) for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) { struct hrtimer *timer; + struct timerqueue_node *next; - if (!base->first) + next = timerqueue_getnext(&base->active); + if (!next) continue; - timer = rb_entry(base->first, struct hrtimer, node); + timer = container_of(next, struct hrtimer, node); + expires = ktime_sub(hrtimer_get_expires(timer), base->offset); /* * clock_was_set() has changed base->offset so the @@ -608,24 +630,23 @@ static int hrtimer_reprogram(struct hrtimer *timer, static void retrigger_next_event(void *arg) { struct hrtimer_cpu_base *base; - struct timespec realtime_offset, wtm; - unsigned long seq; + struct timespec realtime_offset, wtm, sleep; if (!hrtimer_hres_active()) return; - do { - seq = read_seqbegin(&xtime_lock); - wtm = __get_wall_to_monotonic(); - } while (read_seqretry(&xtime_lock, seq)); + get_xtime_and_monotonic_and_sleep_offset(&realtime_offset, &wtm, + &sleep); set_normalized_timespec(&realtime_offset, -wtm.tv_sec, -wtm.tv_nsec); base = &__get_cpu_var(hrtimer_bases); /* Adjust CLOCK_REALTIME offset */ raw_spin_lock(&base->lock); - base->clock_base[CLOCK_REALTIME].offset = + base->clock_base[HRTIMER_BASE_REALTIME].offset = timespec_to_ktime(realtime_offset); + base->clock_base[HRTIMER_BASE_BOOTTIME].offset = + timespec_to_ktime(sleep); hrtimer_force_reprogram(base, 0); raw_spin_unlock(&base->lock); @@ -670,14 +691,6 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) } /* - * Initialize the high resolution related parts of a hrtimer - */ -static inline void hrtimer_init_timer_hres(struct hrtimer *timer) -{ -} - - -/* * When High resolution timers are active, try to reprogram. Note, that in case * the state has HRTIMER_STATE_CALLBACK set, no reprogramming and no expiry * check happens. The timer gets enqueued into the rbtree. The reprogramming @@ -722,8 +735,9 @@ static int hrtimer_switch_to_hres(void) return 0; } base->hres_active = 1; - base->clock_base[CLOCK_REALTIME].resolution = KTIME_HIGH_RES; - base->clock_base[CLOCK_MONOTONIC].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_REALTIME].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_MONOTONIC].resolution = KTIME_HIGH_RES; + base->clock_base[HRTIMER_BASE_BOOTTIME].resolution = KTIME_HIGH_RES; tick_setup_sched_timer(); @@ -747,7 +761,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, return 0; } static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } -static inline void hrtimer_init_timer_hres(struct hrtimer *timer) { } #endif /* CONFIG_HIGH_RES_TIMERS */ @@ -840,48 +853,17 @@ EXPORT_SYMBOL_GPL(hrtimer_forward); static int enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base) { - struct rb_node **link = &base->active.rb_node; - struct rb_node *parent = NULL; - struct hrtimer *entry; - int leftmost = 1; - debug_activate(timer); - /* - * Find the right place in the rbtree: - */ - while (*link) { - parent = *link; - entry = rb_entry(parent, struct hrtimer, node); - /* - * We dont care about collisions. Nodes with - * the same expiry time stay together. - */ - if (hrtimer_get_expires_tv64(timer) < - hrtimer_get_expires_tv64(entry)) { - link = &(*link)->rb_left; - } else { - link = &(*link)->rb_right; - leftmost = 0; - } - } - - /* - * Insert the timer to the rbtree and check whether it - * replaces the first pending timer - */ - if (leftmost) - base->first = &timer->node; + timerqueue_add(&base->active, &timer->node); - rb_link_node(&timer->node, parent, link); - rb_insert_color(&timer->node, &base->active); /* * HRTIMER_STATE_ENQUEUED is or'ed to the current state to preserve the * state of a possibly running callback. */ timer->state |= HRTIMER_STATE_ENQUEUED; - return leftmost; + return (&timer->node == base->active.next); } /* @@ -901,12 +883,7 @@ static void __remove_hrtimer(struct hrtimer *timer, if (!(timer->state & HRTIMER_STATE_ENQUEUED)) goto out; - /* - * Remove the timer from the rbtree and replace the first - * entry pointer if necessary. - */ - if (base->first == &timer->node) { - base->first = rb_next(&timer->node); + if (&timer->node == timerqueue_getnext(&base->active)) { #ifdef CONFIG_HIGH_RES_TIMERS /* Reprogram the clock event device. if enabled */ if (reprogram && hrtimer_hres_active()) { @@ -919,7 +896,7 @@ static void __remove_hrtimer(struct hrtimer *timer, } #endif } - rb_erase(&timer->node, &base->active); + timerqueue_del(&base->active, &timer->node); out: timer->state = newstate; } @@ -1128,11 +1105,13 @@ ktime_t hrtimer_get_next_event(void) if (!hrtimer_hres_active()) { for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++, base++) { struct hrtimer *timer; + struct timerqueue_node *next; - if (!base->first) + next = timerqueue_getnext(&base->active); + if (!next) continue; - timer = rb_entry(base->first, struct hrtimer, node); + timer = container_of(next, struct hrtimer, node); delta.tv64 = hrtimer_get_expires_tv64(timer); delta = ktime_sub(delta, base->get_time()); if (delta.tv64 < mindelta.tv64) @@ -1152,6 +1131,7 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, enum hrtimer_mode mode) { struct hrtimer_cpu_base *cpu_base; + int base; memset(timer, 0, sizeof(struct hrtimer)); @@ -1160,8 +1140,9 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id, if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS) clock_id = CLOCK_MONOTONIC; - timer->base = &cpu_base->clock_base[clock_id]; - hrtimer_init_timer_hres(timer); + base = hrtimer_clockid_to_base(clock_id); + timer->base = &cpu_base->clock_base[base]; + timerqueue_init(&timer->node); #ifdef CONFIG_TIMER_STATS timer->start_site = NULL; @@ -1195,9 +1176,10 @@ EXPORT_SYMBOL_GPL(hrtimer_init); int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) { struct hrtimer_cpu_base *cpu_base; + int base = hrtimer_clockid_to_base(which_clock); cpu_base = &__raw_get_cpu_var(hrtimer_bases); - *tp = ktime_to_timespec(cpu_base->clock_base[which_clock].resolution); + *tp = ktime_to_timespec(cpu_base->clock_base[base].resolution); return 0; } @@ -1278,14 +1260,14 @@ retry: for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { ktime_t basenow; - struct rb_node *node; + struct timerqueue_node *node; basenow = ktime_add(now, base->offset); - while ((node = base->first)) { + while ((node = timerqueue_getnext(&base->active))) { struct hrtimer *timer; - timer = rb_entry(node, struct hrtimer, node); + timer = container_of(node, struct hrtimer, node); /* * The immediate goal for using the softexpires is @@ -1441,7 +1423,7 @@ void hrtimer_run_pending(void) */ void hrtimer_run_queues(void) { - struct rb_node *node; + struct timerqueue_node *node; struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); struct hrtimer_clock_base *base; int index, gettime = 1; @@ -1451,8 +1433,7 @@ void hrtimer_run_queues(void) for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) { base = &cpu_base->clock_base[index]; - - if (!base->first) + if (!timerqueue_getnext(&base->active)) continue; if (gettime) { @@ -1462,10 +1443,10 @@ void hrtimer_run_queues(void) raw_spin_lock(&cpu_base->lock); - while ((node = base->first)) { + while ((node = timerqueue_getnext(&base->active))) { struct hrtimer *timer; - timer = rb_entry(node, struct hrtimer, node); + timer = container_of(node, struct hrtimer, node); if (base->softirq_time.tv64 <= hrtimer_get_expires_tv64(timer)) break; @@ -1630,8 +1611,10 @@ static void __cpuinit init_hrtimers_cpu(int cpu) raw_spin_lock_init(&cpu_base->lock); - for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) + for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { cpu_base->clock_base[i].cpu_base = cpu_base; + timerqueue_init_head(&cpu_base->clock_base[i].active); + } hrtimer_init_hres(cpu_base); } @@ -1642,10 +1625,10 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, struct hrtimer_clock_base *new_base) { struct hrtimer *timer; - struct rb_node *node; + struct timerqueue_node *node; - while ((node = rb_first(&old_base->active))) { - timer = rb_entry(node, struct hrtimer, node); + while ((node = timerqueue_getnext(&old_base->active))) { + timer = container_of(node, struct hrtimer, node); BUG_ON(hrtimer_callback_running(timer)); debug_deactivate(timer); @@ -1774,7 +1757,7 @@ schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta, } /* - * A NULL parameter means "inifinte" + * A NULL parameter means "infinite" */ if (!expires) { schedule(); diff --git a/kernel/hung_task.c b/kernel/hung_task.c index 53ead174da2..ea640120ab8 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -33,7 +33,7 @@ unsigned long __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT; /* * Zero means infinite timeout - no checking done: */ -unsigned long __read_mostly sysctl_hung_task_timeout_secs = 120; +unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_TASK_TIMEOUT; unsigned long __read_mostly sysctl_hung_task_warnings = 10; diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 31d766bf5d2..d1d051b38e0 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -1,5 +1,6 @@ +# Select this to activate the generic irq options below config HAVE_GENERIC_HARDIRQS - def_bool n + bool if HAVE_GENERIC_HARDIRQS menu "IRQ subsystem" @@ -9,31 +10,51 @@ menu "IRQ subsystem" config GENERIC_HARDIRQS def_bool y -config GENERIC_HARDIRQS_NO__DO_IRQ - def_bool y - -# Select this to disable the deprecated stuff -config GENERIC_HARDIRQS_NO_DEPRECATED - def_bool n - # Options selectable by the architecture code + +# Make sparse irq Kconfig switch below available config HAVE_SPARSE_IRQ - def_bool n + bool +# Enable the generic irq autoprobe mechanism config GENERIC_IRQ_PROBE - def_bool n + bool + +# Use the generic /proc/interrupts implementation +config GENERIC_IRQ_SHOW + bool + +# Print level/edge extra information +config GENERIC_IRQ_SHOW_LEVEL + bool +# Support for delayed migration from interrupt context config GENERIC_PENDING_IRQ - def_bool n + bool +# Alpha specific irq affinity mechanism config AUTO_IRQ_AFFINITY - def_bool n - -config IRQ_PER_CPU - def_bool n + bool +# Tasklet based software resend for pending interrupts on enable_irq() config HARDIRQS_SW_RESEND - def_bool n + bool + +# Preflow handler support for fasteoi (sparc64) +config IRQ_PREFLOW_FASTEOI + bool + +# Edge style eoi based handler (cell) +config IRQ_EDGE_EOI_HANDLER + bool + +# Generic configurable interrupt chip implementation +config GENERIC_IRQ_CHIP + bool + +# Support forced irq threading +config IRQ_FORCED_THREADING + bool config SPARSE_IRQ bool "Support sparse irq numbering" diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index 54329cd7b3e..73290056cfb 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -1,5 +1,6 @@ obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o +obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c index 505798f86c3..342d8f44e40 100644 --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -17,7 +17,7 @@ /* * Autodetection depends on the fact that any interrupt that * comes in on to an unassigned handler will get stuck with - * "IRQ_WAITING" cleared and the interrupt disabled. + * "IRQS_WAITING" cleared and the interrupt disabled. */ static DEFINE_MUTEX(probing_active); @@ -32,7 +32,6 @@ unsigned long probe_irq_on(void) { struct irq_desc *desc; unsigned long mask = 0; - unsigned int status; int i; /* @@ -46,13 +45,7 @@ unsigned long probe_irq_on(void) */ for_each_irq_desc_reverse(i, desc) { raw_spin_lock_irq(&desc->lock); - if (!desc->action && !(desc->status & IRQ_NOPROBE)) { - /* - * An old-style architecture might still have - * the handle_bad_irq handler there: - */ - compat_irq_chip_set_default_handler(desc); - + if (!desc->action && irq_settings_can_probe(desc)) { /* * Some chips need to know about probing in * progress: @@ -60,7 +53,7 @@ unsigned long probe_irq_on(void) if (desc->irq_data.chip->irq_set_type) desc->irq_data.chip->irq_set_type(&desc->irq_data, IRQ_TYPE_PROBE); - desc->irq_data.chip->irq_startup(&desc->irq_data); + irq_startup(desc); } raw_spin_unlock_irq(&desc->lock); } @@ -75,10 +68,10 @@ unsigned long probe_irq_on(void) */ for_each_irq_desc_reverse(i, desc) { raw_spin_lock_irq(&desc->lock); - if (!desc->action && !(desc->status & IRQ_NOPROBE)) { - desc->status |= IRQ_AUTODETECT | IRQ_WAITING; - if (desc->irq_data.chip->irq_startup(&desc->irq_data)) - desc->status |= IRQ_PENDING; + if (!desc->action && irq_settings_can_probe(desc)) { + desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; + if (irq_startup(desc)) + desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); } @@ -93,13 +86,12 @@ unsigned long probe_irq_on(void) */ for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); - status = desc->status; - if (status & IRQ_AUTODETECT) { + if (desc->istate & IRQS_AUTODETECT) { /* It triggered already - consider it spurious. */ - if (!(status & IRQ_WAITING)) { - desc->status = status & ~IRQ_AUTODETECT; - desc->irq_data.chip->irq_shutdown(&desc->irq_data); + if (!(desc->istate & IRQS_WAITING)) { + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); } else if (i < 32) mask |= 1 << i; @@ -125,20 +117,18 @@ EXPORT_SYMBOL(probe_irq_on); */ unsigned int probe_irq_mask(unsigned long val) { - unsigned int status, mask = 0; + unsigned int mask = 0; struct irq_desc *desc; int i; for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (i < 16 && !(status & IRQ_WAITING)) + if (desc->istate & IRQS_AUTODETECT) { + if (i < 16 && !(desc->istate & IRQS_WAITING)) mask |= 1 << i; - desc->status = status & ~IRQ_AUTODETECT; - desc->irq_data.chip->irq_shutdown(&desc->irq_data); + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); } raw_spin_unlock_irq(&desc->lock); } @@ -169,20 +159,18 @@ int probe_irq_off(unsigned long val) { int i, irq_found = 0, nr_of_irqs = 0; struct irq_desc *desc; - unsigned int status; for_each_irq_desc(i, desc) { raw_spin_lock_irq(&desc->lock); - status = desc->status; - if (status & IRQ_AUTODETECT) { - if (!(status & IRQ_WAITING)) { + if (desc->istate & IRQS_AUTODETECT) { + if (!(desc->istate & IRQS_WAITING)) { if (!nr_of_irqs) irq_found = i; nr_of_irqs++; } - desc->status = status & ~IRQ_AUTODETECT; - desc->irq_data.chip->irq_shutdown(&desc->irq_data); + desc->istate &= ~IRQS_AUTODETECT; + irq_shutdown(desc); } raw_spin_unlock_irq(&desc->lock); } diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index baa5c4acad8..d5a3009da71 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -19,140 +19,115 @@ #include "internals.h" /** - * set_irq_chip - set the irq chip for an irq + * irq_set_chip - set the irq chip for an irq * @irq: irq number * @chip: pointer to irq chip description structure */ -int set_irq_chip(unsigned int irq, struct irq_chip *chip) +int irq_set_chip(unsigned int irq, struct irq_chip *chip) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); - if (!desc) { - WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq); + if (!desc) return -EINVAL; - } if (!chip) chip = &no_irq_chip; - raw_spin_lock_irqsave(&desc->lock, flags); - irq_chip_set_defaults(chip); desc->irq_data.chip = chip; - raw_spin_unlock_irqrestore(&desc->lock, flags); - + irq_put_desc_unlock(desc, flags); + /* + * For !CONFIG_SPARSE_IRQ make the irq show up in + * allocated_irqs. For the CONFIG_SPARSE_IRQ case, it is + * already marked, and this call is harmless. + */ + irq_reserve_irq(irq); return 0; } -EXPORT_SYMBOL(set_irq_chip); +EXPORT_SYMBOL(irq_set_chip); /** - * set_irq_type - set the irq trigger type for an irq + * irq_set_type - set the irq trigger type for an irq * @irq: irq number * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h */ -int set_irq_type(unsigned int irq, unsigned int type) +int irq_set_irq_type(unsigned int irq, unsigned int type) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; - int ret = -ENXIO; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + int ret = 0; - if (!desc) { - printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq); - return -ENODEV; - } + if (!desc) + return -EINVAL; type &= IRQ_TYPE_SENSE_MASK; - if (type == IRQ_TYPE_NONE) - return 0; - - raw_spin_lock_irqsave(&desc->lock, flags); - ret = __irq_set_trigger(desc, irq, type); - raw_spin_unlock_irqrestore(&desc->lock, flags); + if (type != IRQ_TYPE_NONE) + ret = __irq_set_trigger(desc, irq, type); + irq_put_desc_busunlock(desc, flags); return ret; } -EXPORT_SYMBOL(set_irq_type); +EXPORT_SYMBOL(irq_set_irq_type); /** - * set_irq_data - set irq type data for an irq + * irq_set_handler_data - set irq handler data for an irq * @irq: Interrupt number * @data: Pointer to interrupt specific data * * Set the hardware irq controller data for an irq */ -int set_irq_data(unsigned int irq, void *data) +int irq_set_handler_data(unsigned int irq, void *data) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); - if (!desc) { - printk(KERN_ERR - "Trying to install controller data for IRQ%d\n", irq); + if (!desc) return -EINVAL; - } - - raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.handler_data = data; - raw_spin_unlock_irqrestore(&desc->lock, flags); + irq_put_desc_unlock(desc, flags); return 0; } -EXPORT_SYMBOL(set_irq_data); +EXPORT_SYMBOL(irq_set_handler_data); /** - * set_irq_msi - set MSI descriptor data for an irq + * irq_set_msi_desc - set MSI descriptor data for an irq * @irq: Interrupt number * @entry: Pointer to MSI descriptor data * * Set the MSI descriptor entry for an irq */ -int set_irq_msi(unsigned int irq, struct msi_desc *entry) +int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); - if (!desc) { - printk(KERN_ERR - "Trying to install msi data for IRQ%d\n", irq); + if (!desc) return -EINVAL; - } - - raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.msi_desc = entry; if (entry) entry->irq = irq; - raw_spin_unlock_irqrestore(&desc->lock, flags); + irq_put_desc_unlock(desc, flags); return 0; } /** - * set_irq_chip_data - set irq chip data for an irq + * irq_set_chip_data - set irq chip data for an irq * @irq: Interrupt number * @data: Pointer to chip specific data * * Set the hardware irq chip data for an irq */ -int set_irq_chip_data(unsigned int irq, void *data) +int irq_set_chip_data(unsigned int irq, void *data) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); - if (!desc) { - printk(KERN_ERR - "Trying to install chip data for IRQ%d\n", irq); - return -EINVAL; - } - - if (!desc->irq_data.chip) { - printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq); + if (!desc) return -EINVAL; - } - - raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.chip_data = data; - raw_spin_unlock_irqrestore(&desc->lock, flags); - + irq_put_desc_unlock(desc, flags); return 0; } -EXPORT_SYMBOL(set_irq_chip_data); +EXPORT_SYMBOL(irq_set_chip_data); struct irq_data *irq_get_irq_data(unsigned int irq) { @@ -162,221 +137,71 @@ struct irq_data *irq_get_irq_data(unsigned int irq) } EXPORT_SYMBOL_GPL(irq_get_irq_data); -/** - * set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq - * - * @irq: Interrupt number - * @nest: 0 to clear / 1 to set the IRQ_NESTED_THREAD flag - * - * The IRQ_NESTED_THREAD flag indicates that on - * request_threaded_irq() no separate interrupt thread should be - * created for the irq as the handler are called nested in the - * context of a demultiplexing interrupt handler thread. - */ -void set_irq_nested_thread(unsigned int irq, int nest) -{ - struct irq_desc *desc = irq_to_desc(irq); - unsigned long flags; - - if (!desc) - return; - - raw_spin_lock_irqsave(&desc->lock, flags); - if (nest) - desc->status |= IRQ_NESTED_THREAD; - else - desc->status &= ~IRQ_NESTED_THREAD; - raw_spin_unlock_irqrestore(&desc->lock, flags); -} -EXPORT_SYMBOL_GPL(set_irq_nested_thread); - -/* - * default enable function - */ -static void default_enable(struct irq_data *data) +static void irq_state_clr_disabled(struct irq_desc *desc) { - struct irq_desc *desc = irq_data_to_desc(data); - - desc->irq_data.chip->irq_unmask(&desc->irq_data); - desc->status &= ~IRQ_MASKED; + irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED); } -/* - * default disable function - */ -static void default_disable(struct irq_data *data) -{ -} - -/* - * default startup function - */ -static unsigned int default_startup(struct irq_data *data) +static void irq_state_set_disabled(struct irq_desc *desc) { - struct irq_desc *desc = irq_data_to_desc(data); - - desc->irq_data.chip->irq_enable(data); - return 0; + irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); } -/* - * default shutdown function - */ -static void default_shutdown(struct irq_data *data) +static void irq_state_clr_masked(struct irq_desc *desc) { - struct irq_desc *desc = irq_data_to_desc(data); - - desc->irq_data.chip->irq_mask(&desc->irq_data); - desc->status |= IRQ_MASKED; + irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED); } -#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED -/* Temporary migration helpers */ -static void compat_irq_mask(struct irq_data *data) +static void irq_state_set_masked(struct irq_desc *desc) { - data->chip->mask(data->irq); + irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); } -static void compat_irq_unmask(struct irq_data *data) +int irq_startup(struct irq_desc *desc) { - data->chip->unmask(data->irq); -} + irq_state_clr_disabled(desc); + desc->depth = 0; -static void compat_irq_ack(struct irq_data *data) -{ - data->chip->ack(data->irq); -} - -static void compat_irq_mask_ack(struct irq_data *data) -{ - data->chip->mask_ack(data->irq); -} - -static void compat_irq_eoi(struct irq_data *data) -{ - data->chip->eoi(data->irq); -} - -static void compat_irq_enable(struct irq_data *data) -{ - data->chip->enable(data->irq); -} - -static void compat_irq_disable(struct irq_data *data) -{ - data->chip->disable(data->irq); -} - -static void compat_irq_shutdown(struct irq_data *data) -{ - data->chip->shutdown(data->irq); -} - -static unsigned int compat_irq_startup(struct irq_data *data) -{ - return data->chip->startup(data->irq); -} - -static int compat_irq_set_affinity(struct irq_data *data, - const struct cpumask *dest, bool force) -{ - return data->chip->set_affinity(data->irq, dest); -} - -static int compat_irq_set_type(struct irq_data *data, unsigned int type) -{ - return data->chip->set_type(data->irq, type); -} - -static int compat_irq_set_wake(struct irq_data *data, unsigned int on) -{ - return data->chip->set_wake(data->irq, on); -} + if (desc->irq_data.chip->irq_startup) { + int ret = desc->irq_data.chip->irq_startup(&desc->irq_data); + irq_state_clr_masked(desc); + return ret; + } -static int compat_irq_retrigger(struct irq_data *data) -{ - return data->chip->retrigger(data->irq); + irq_enable(desc); + return 0; } -static void compat_bus_lock(struct irq_data *data) +void irq_shutdown(struct irq_desc *desc) { - data->chip->bus_lock(data->irq); + irq_state_set_disabled(desc); + desc->depth = 1; + if (desc->irq_data.chip->irq_shutdown) + desc->irq_data.chip->irq_shutdown(&desc->irq_data); + if (desc->irq_data.chip->irq_disable) + desc->irq_data.chip->irq_disable(&desc->irq_data); + else + desc->irq_data.chip->irq_mask(&desc->irq_data); + irq_state_set_masked(desc); } -static void compat_bus_sync_unlock(struct irq_data *data) +void irq_enable(struct irq_desc *desc) { - data->chip->bus_sync_unlock(data->irq); + irq_state_clr_disabled(desc); + if (desc->irq_data.chip->irq_enable) + desc->irq_data.chip->irq_enable(&desc->irq_data); + else + desc->irq_data.chip->irq_unmask(&desc->irq_data); + irq_state_clr_masked(desc); } -#endif -/* - * Fixup enable/disable function pointers - */ -void irq_chip_set_defaults(struct irq_chip *chip) +void irq_disable(struct irq_desc *desc) { -#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED - /* - * Compat fixup functions need to be before we set the - * defaults for enable/disable/startup/shutdown - */ - if (chip->enable) - chip->irq_enable = compat_irq_enable; - if (chip->disable) - chip->irq_disable = compat_irq_disable; - if (chip->shutdown) - chip->irq_shutdown = compat_irq_shutdown; - if (chip->startup) - chip->irq_startup = compat_irq_startup; -#endif - /* - * The real defaults - */ - if (!chip->irq_enable) - chip->irq_enable = default_enable; - if (!chip->irq_disable) - chip->irq_disable = default_disable; - if (!chip->irq_startup) - chip->irq_startup = default_startup; - /* - * We use chip->irq_disable, when the user provided its own. When - * we have default_disable set for chip->irq_disable, then we need - * to use default_shutdown, otherwise the irq line is not - * disabled on free_irq(): - */ - if (!chip->irq_shutdown) - chip->irq_shutdown = chip->irq_disable != default_disable ? - chip->irq_disable : default_shutdown; - -#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED - if (!chip->end) - chip->end = dummy_irq_chip.end; - - /* - * Now fix up the remaining compat handlers - */ - if (chip->bus_lock) - chip->irq_bus_lock = compat_bus_lock; - if (chip->bus_sync_unlock) - chip->irq_bus_sync_unlock = compat_bus_sync_unlock; - if (chip->mask) - chip->irq_mask = compat_irq_mask; - if (chip->unmask) - chip->irq_unmask = compat_irq_unmask; - if (chip->ack) - chip->irq_ack = compat_irq_ack; - if (chip->mask_ack) - chip->irq_mask_ack = compat_irq_mask_ack; - if (chip->eoi) - chip->irq_eoi = compat_irq_eoi; - if (chip->set_affinity) - chip->irq_set_affinity = compat_irq_set_affinity; - if (chip->set_type) - chip->irq_set_type = compat_irq_set_type; - if (chip->set_wake) - chip->irq_set_wake = compat_irq_set_wake; - if (chip->retrigger) - chip->irq_retrigger = compat_irq_retrigger; -#endif + irq_state_set_disabled(desc); + if (desc->irq_data.chip->irq_disable) { + desc->irq_data.chip->irq_disable(&desc->irq_data); + irq_state_set_masked(desc); + } } static inline void mask_ack_irq(struct irq_desc *desc) @@ -388,22 +213,22 @@ static inline void mask_ack_irq(struct irq_desc *desc) if (desc->irq_data.chip->irq_ack) desc->irq_data.chip->irq_ack(&desc->irq_data); } - desc->status |= IRQ_MASKED; + irq_state_set_masked(desc); } -static inline void mask_irq(struct irq_desc *desc) +void mask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_mask) { desc->irq_data.chip->irq_mask(&desc->irq_data); - desc->status |= IRQ_MASKED; + irq_state_set_masked(desc); } } -static inline void unmask_irq(struct irq_desc *desc) +void unmask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_unmask) { desc->irq_data.chip->irq_unmask(&desc->irq_data); - desc->status &= ~IRQ_MASKED; + irq_state_clr_masked(desc); } } @@ -428,10 +253,10 @@ void handle_nested_irq(unsigned int irq) kstat_incr_irqs_this_cpu(irq, desc); action = desc->action; - if (unlikely(!action || (desc->status & IRQ_DISABLED))) + if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) goto out_unlock; - desc->status |= IRQ_INPROGRESS; + irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); raw_spin_unlock_irq(&desc->lock); action_ret = action->thread_fn(action->irq, action->dev_id); @@ -439,13 +264,20 @@ void handle_nested_irq(unsigned int irq) note_interrupt(irq, desc, action_ret); raw_spin_lock_irq(&desc->lock); - desc->status &= ~IRQ_INPROGRESS; + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); out_unlock: raw_spin_unlock_irq(&desc->lock); } EXPORT_SYMBOL_GPL(handle_nested_irq); +static bool irq_check_poll(struct irq_desc *desc) +{ + if (!(desc->istate & IRQS_POLL_INPROGRESS)) + return false; + return irq_wait_for_poll(desc); +} + /** * handle_simple_irq - Simple and software-decoded IRQs. * @irq: the interrupt number @@ -461,32 +293,24 @@ EXPORT_SYMBOL_GPL(handle_nested_irq); void handle_simple_irq(unsigned int irq, struct irq_desc *desc) { - struct irqaction *action; - irqreturn_t action_ret; - raw_spin_lock(&desc->lock); - if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out_unlock; - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out_unlock; + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); - action = desc->action; - if (unlikely(!action || (desc->status & IRQ_DISABLED))) + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) goto out_unlock; - desc->status |= IRQ_INPROGRESS; - raw_spin_unlock(&desc->lock); + handle_irq_event(desc); - action_ret = handle_IRQ_event(irq, action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - - raw_spin_lock(&desc->lock); - desc->status &= ~IRQ_INPROGRESS; out_unlock: raw_spin_unlock(&desc->lock); } +EXPORT_SYMBOL_GPL(handle_simple_irq); /** * handle_level_irq - Level type irq handler @@ -501,42 +325,42 @@ out_unlock: void handle_level_irq(unsigned int irq, struct irq_desc *desc) { - struct irqaction *action; - irqreturn_t action_ret; - raw_spin_lock(&desc->lock); mask_ack_irq(desc); - if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out_unlock; - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out_unlock; + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * keep it masked and get out of here */ - action = desc->action; - if (unlikely(!action || (desc->status & IRQ_DISABLED))) + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) goto out_unlock; - desc->status |= IRQ_INPROGRESS; - raw_spin_unlock(&desc->lock); - - action_ret = handle_IRQ_event(irq, action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - - raw_spin_lock(&desc->lock); - desc->status &= ~IRQ_INPROGRESS; + handle_irq_event(desc); - if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT))) + if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT)) unmask_irq(desc); out_unlock: raw_spin_unlock(&desc->lock); } EXPORT_SYMBOL_GPL(handle_level_irq); +#ifdef CONFIG_IRQ_PREFLOW_FASTEOI +static inline void preflow_handler(struct irq_desc *desc) +{ + if (desc->preflow_handler) + desc->preflow_handler(&desc->irq_data); +} +#else +static inline void preflow_handler(struct irq_desc *desc) { } +#endif + /** * handle_fasteoi_irq - irq handler for transparent controllers * @irq: the interrupt number @@ -550,42 +374,40 @@ EXPORT_SYMBOL_GPL(handle_level_irq); void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) { - struct irqaction *action; - irqreturn_t action_ret; - raw_spin_lock(&desc->lock); - if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out; + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) + if (!irq_check_poll(desc)) + goto out; - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * then mask it and get out of here: */ - action = desc->action; - if (unlikely(!action || (desc->status & IRQ_DISABLED))) { - desc->status |= IRQ_PENDING; + if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { + desc->istate |= IRQS_PENDING; mask_irq(desc); goto out; } - desc->status |= IRQ_INPROGRESS; - desc->status &= ~IRQ_PENDING; - raw_spin_unlock(&desc->lock); + if (desc->istate & IRQS_ONESHOT) + mask_irq(desc); - action_ret = handle_IRQ_event(irq, action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); + preflow_handler(desc); + handle_irq_event(desc); - raw_spin_lock(&desc->lock); - desc->status &= ~IRQ_INPROGRESS; -out: +out_eoi: desc->irq_data.chip->irq_eoi(&desc->irq_data); - +out_unlock: raw_spin_unlock(&desc->lock); + return; +out: + if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED)) + goto out_eoi; + goto out_unlock; } /** @@ -594,7 +416,7 @@ out: * @desc: the interrupt description structure for this irq * * Interrupt occures on the falling and/or rising edge of a hardware - * signal. The occurence is latched into the irq controller hardware + * signal. The occurrence is latched into the irq controller hardware * and must be acked in order to be reenabled. After the ack another * interrupt can happen on the same source even before the first one * is handled by the associated event handler. If this happens it @@ -609,32 +431,27 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); - + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); /* * If we're currently running this IRQ, or its disabled, * we shouldn't process the IRQ. Mark it pending, handle * the necessary masking and go out */ - if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) || - !desc->action)) { - desc->status |= (IRQ_PENDING | IRQ_MASKED); - mask_ack_irq(desc); - goto out_unlock; + if (unlikely(irqd_irq_disabled(&desc->irq_data) || + irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (!irq_check_poll(desc)) { + desc->istate |= IRQS_PENDING; + mask_ack_irq(desc); + goto out_unlock; + } } kstat_incr_irqs_this_cpu(irq, desc); /* Start handling the irq */ desc->irq_data.chip->irq_ack(&desc->irq_data); - /* Mark the IRQ currently in progress.*/ - desc->status |= IRQ_INPROGRESS; - do { - struct irqaction *action = desc->action; - irqreturn_t action_ret; - - if (unlikely(!action)) { + if (unlikely(!desc->action)) { mask_irq(desc); goto out_unlock; } @@ -644,26 +461,66 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc) * one, we could have masked the irq. * Renable it, if it was not disabled in meantime. */ - if (unlikely((desc->status & - (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) == - (IRQ_PENDING | IRQ_MASKED))) { - unmask_irq(desc); + if (unlikely(desc->istate & IRQS_PENDING)) { + if (!irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data)) + unmask_irq(desc); } - desc->status &= ~IRQ_PENDING; - raw_spin_unlock(&desc->lock); - action_ret = handle_IRQ_event(irq, action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - raw_spin_lock(&desc->lock); + handle_irq_event(desc); - } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING); + } while ((desc->istate & IRQS_PENDING) && + !irqd_irq_disabled(&desc->irq_data)); - desc->status &= ~IRQ_INPROGRESS; out_unlock: raw_spin_unlock(&desc->lock); } +#ifdef CONFIG_IRQ_EDGE_EOI_HANDLER +/** + * handle_edge_eoi_irq - edge eoi type IRQ handler + * @irq: the interrupt number + * @desc: the interrupt description structure for this irq + * + * Similar as the above handle_edge_irq, but using eoi and w/o the + * mask/unmask logic. + */ +void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + + raw_spin_lock(&desc->lock); + + desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); + /* + * If we're currently running this IRQ, or its disabled, + * we shouldn't process the IRQ. Mark it pending, handle + * the necessary masking and go out + */ + if (unlikely(irqd_irq_disabled(&desc->irq_data) || + irqd_irq_inprogress(&desc->irq_data) || !desc->action)) { + if (!irq_check_poll(desc)) { + desc->istate |= IRQS_PENDING; + goto out_eoi; + } + } + kstat_incr_irqs_this_cpu(irq, desc); + + do { + if (unlikely(!desc->action)) + goto out_eoi; + + handle_irq_event(desc); + + } while ((desc->istate & IRQS_PENDING) && + !irqd_irq_disabled(&desc->irq_data)); + +out_eoi: + chip->irq_eoi(&desc->irq_data); + raw_spin_unlock(&desc->lock); +} +#endif + /** * handle_percpu_irq - Per CPU local irq handler * @irq: the interrupt number @@ -674,103 +531,147 @@ out_unlock: void handle_percpu_irq(unsigned int irq, struct irq_desc *desc) { - irqreturn_t action_ret; + struct irq_chip *chip = irq_desc_get_chip(desc); kstat_incr_irqs_this_cpu(irq, desc); - if (desc->irq_data.chip->irq_ack) - desc->irq_data.chip->irq_ack(&desc->irq_data); + if (chip->irq_ack) + chip->irq_ack(&desc->irq_data); - action_ret = handle_IRQ_event(irq, desc->action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); + handle_irq_event_percpu(desc, desc->action); - if (desc->irq_data.chip->irq_eoi) - desc->irq_data.chip->irq_eoi(&desc->irq_data); + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); } void -__set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, +__irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, const char *name) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); - if (!desc) { - printk(KERN_ERR - "Trying to install type control for IRQ%d\n", irq); + if (!desc) return; - } - if (!handle) + if (!handle) { handle = handle_bad_irq; - else if (desc->irq_data.chip == &no_irq_chip) { - printk(KERN_WARNING "Trying to install %sinterrupt handler " - "for IRQ%d\n", is_chained ? "chained " : "", irq); - /* - * Some ARM implementations install a handler for really dumb - * interrupt hardware without setting an irq_chip. This worked - * with the ARM no_irq_chip but the check in setup_irq would - * prevent us to setup the interrupt at all. Switch it to - * dummy_irq_chip for easy transition. - */ - desc->irq_data.chip = &dummy_irq_chip; + } else { + if (WARN_ON(desc->irq_data.chip == &no_irq_chip)) + goto out; } - chip_bus_lock(desc); - raw_spin_lock_irqsave(&desc->lock, flags); - /* Uninstall? */ if (handle == handle_bad_irq) { if (desc->irq_data.chip != &no_irq_chip) mask_ack_irq(desc); - desc->status |= IRQ_DISABLED; + irq_state_set_disabled(desc); desc->depth = 1; } desc->handle_irq = handle; desc->name = name; if (handle != handle_bad_irq && is_chained) { - desc->status &= ~IRQ_DISABLED; - desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE; - desc->depth = 0; - desc->irq_data.chip->irq_startup(&desc->irq_data); + irq_settings_set_noprobe(desc); + irq_settings_set_norequest(desc); + irq_settings_set_nothread(desc); + irq_startup(desc); } - raw_spin_unlock_irqrestore(&desc->lock, flags); - chip_bus_sync_unlock(desc); -} -EXPORT_SYMBOL_GPL(__set_irq_handler); - -void -set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip, - irq_flow_handler_t handle) -{ - set_irq_chip(irq, chip); - __set_irq_handler(irq, handle, 0, NULL); +out: + irq_put_desc_busunlock(desc, flags); } +EXPORT_SYMBOL_GPL(__irq_set_handler); void -set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip, +irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip, irq_flow_handler_t handle, const char *name) { - set_irq_chip(irq, chip); - __set_irq_handler(irq, handle, 0, name); + irq_set_chip(irq, chip); + __irq_set_handler(irq, handle, 0, name); } void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); if (!desc) return; + irq_settings_clr_and_set(desc, clr, set); + + irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU | + IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT); + if (irq_settings_has_no_balance_set(desc)) + irqd_set(&desc->irq_data, IRQD_NO_BALANCING); + if (irq_settings_is_per_cpu(desc)) + irqd_set(&desc->irq_data, IRQD_PER_CPU); + if (irq_settings_can_move_pcntxt(desc)) + irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); + if (irq_settings_is_level(desc)) + irqd_set(&desc->irq_data, IRQD_LEVEL); + + irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc)); + + irq_put_desc_unlock(desc, flags); +} +EXPORT_SYMBOL_GPL(irq_modify_status); + +/** + * irq_cpu_online - Invoke all irq_cpu_online functions. + * + * Iterate through all irqs and invoke the chip.irq_cpu_online() + * for each. + */ +void irq_cpu_online(void) +{ + struct irq_desc *desc; + struct irq_chip *chip; + unsigned long flags; + unsigned int irq; + + for_each_active_irq(irq) { + desc = irq_to_desc(irq); + if (!desc) + continue; - /* Sanitize flags */ - set &= IRQF_MODIFY_MASK; - clr &= IRQF_MODIFY_MASK; + raw_spin_lock_irqsave(&desc->lock, flags); - raw_spin_lock_irqsave(&desc->lock, flags); - desc->status &= ~clr; - desc->status |= set; - raw_spin_unlock_irqrestore(&desc->lock, flags); + chip = irq_data_get_irq_chip(&desc->irq_data); + if (chip && chip->irq_cpu_online && + (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || + !irqd_irq_disabled(&desc->irq_data))) + chip->irq_cpu_online(&desc->irq_data); + + raw_spin_unlock_irqrestore(&desc->lock, flags); + } +} + +/** + * irq_cpu_offline - Invoke all irq_cpu_offline functions. + * + * Iterate through all irqs and invoke the chip.irq_cpu_offline() + * for each. + */ +void irq_cpu_offline(void) +{ + struct irq_desc *desc; + struct irq_chip *chip; + unsigned long flags; + unsigned int irq; + + for_each_active_irq(irq) { + desc = irq_to_desc(irq); + if (!desc) + continue; + + raw_spin_lock_irqsave(&desc->lock, flags); + + chip = irq_data_get_irq_chip(&desc->irq_data); + if (chip && chip->irq_cpu_offline && + (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || + !irqd_irq_disabled(&desc->irq_data))) + chip->irq_cpu_offline(&desc->irq_data); + + raw_spin_unlock_irqrestore(&desc->lock, flags); + } } diff --git a/kernel/irq/debug.h b/kernel/irq/debug.h new file mode 100644 index 00000000000..97a8bfadc88 --- /dev/null +++ b/kernel/irq/debug.h @@ -0,0 +1,45 @@ +/* + * Debugging printout: + */ + +#include <linux/kallsyms.h> + +#define P(f) if (desc->status_use_accessors & f) printk("%14s set\n", #f) +#define PS(f) if (desc->istate & f) printk("%14s set\n", #f) +/* FIXME */ +#define PD(f) do { } while (0) + +static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc) +{ + printk("irq %d, desc: %p, depth: %d, count: %d, unhandled: %d\n", + irq, desc, desc->depth, desc->irq_count, desc->irqs_unhandled); + printk("->handle_irq(): %p, ", desc->handle_irq); + print_symbol("%s\n", (unsigned long)desc->handle_irq); + printk("->irq_data.chip(): %p, ", desc->irq_data.chip); + print_symbol("%s\n", (unsigned long)desc->irq_data.chip); + printk("->action(): %p\n", desc->action); + if (desc->action) { + printk("->action->handler(): %p, ", desc->action->handler); + print_symbol("%s\n", (unsigned long)desc->action->handler); + } + + P(IRQ_LEVEL); + P(IRQ_PER_CPU); + P(IRQ_NOPROBE); + P(IRQ_NOREQUEST); + P(IRQ_NOTHREAD); + P(IRQ_NOAUTOEN); + + PS(IRQS_AUTODETECT); + PS(IRQS_REPLAY); + PS(IRQS_WAITING); + PS(IRQS_PENDING); + + PD(IRQS_INPROGRESS); + PD(IRQS_DISABLED); + PD(IRQS_MASKED); +} + +#undef P +#undef PS +#undef PD diff --git a/kernel/irq/dummychip.c b/kernel/irq/dummychip.c index 20dc5474947..b5fcd96c710 100644 --- a/kernel/irq/dummychip.c +++ b/kernel/irq/dummychip.c @@ -31,13 +31,6 @@ static unsigned int noop_ret(struct irq_data *data) return 0; } -#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED -static void compat_noop(unsigned int irq) { } -#define END_INIT .end = compat_noop -#else -#define END_INIT -#endif - /* * Generic no controller implementation */ @@ -48,7 +41,6 @@ struct irq_chip no_irq_chip = { .irq_enable = noop, .irq_disable = noop, .irq_ack = ack_bad, - END_INIT }; /* @@ -64,5 +56,4 @@ struct irq_chip dummy_irq_chip = { .irq_ack = noop, .irq_mask = noop, .irq_unmask = noop, - END_INIT }; diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c new file mode 100644 index 00000000000..31a9db71190 --- /dev/null +++ b/kernel/irq/generic-chip.c @@ -0,0 +1,354 @@ +/* + * Library implementing the most common irq chip callback functions + * + * Copyright (C) 2011, Thomas Gleixner + */ +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/syscore_ops.h> + +#include "internals.h" + +static LIST_HEAD(gc_list); +static DEFINE_RAW_SPINLOCK(gc_lock); + +static inline struct irq_chip_regs *cur_regs(struct irq_data *d) +{ + return &container_of(d->chip, struct irq_chip_type, chip)->regs; +} + +/** + * irq_gc_noop - NOOP function + * @d: irq_data + */ +void irq_gc_noop(struct irq_data *d) +{ +} + +/** + * irq_gc_mask_disable_reg - Mask chip via disable register + * @d: irq_data + * + * Chip has separate enable/disable registers instead of a single mask + * register. + */ +void irq_gc_mask_disable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->disable); + gc->mask_cache &= ~mask; + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_set_mask_bit - Mask chip via setting bit in mask register + * @d: irq_data + * + * Chip has a single mask register. Values of this register are cached + * and protected by gc->lock + */ +void irq_gc_mask_set_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + gc->mask_cache |= mask; + irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask); + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_set_mask_bit - Mask chip via clearing bit in mask register + * @d: irq_data + * + * Chip has a single mask register. Values of this register are cached + * and protected by gc->lock + */ +void irq_gc_mask_clr_bit(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + gc->mask_cache &= ~mask; + irq_reg_writel(gc->mask_cache, gc->reg_base + cur_regs(d)->mask); + irq_gc_unlock(gc); +} + +/** + * irq_gc_unmask_enable_reg - Unmask chip via enable register + * @d: irq_data + * + * Chip has separate enable/disable registers instead of a single mask + * register. + */ +void irq_gc_unmask_enable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->enable); + gc->mask_cache |= mask; + irq_gc_unlock(gc); +} + +/** + * irq_gc_ack - Ack pending interrupt + * @d: irq_data + */ +void irq_gc_ack(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack); + irq_gc_unlock(gc); +} + +/** + * irq_gc_mask_disable_reg_and_ack- Mask and ack pending interrupt + * @d: irq_data + */ +void irq_gc_mask_disable_reg_and_ack(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->mask); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->ack); + irq_gc_unlock(gc); +} + +/** + * irq_gc_eoi - EOI interrupt + * @d: irq_data + */ +void irq_gc_eoi(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + irq_gc_lock(gc); + irq_reg_writel(mask, gc->reg_base + cur_regs(d)->eoi); + irq_gc_unlock(gc); +} + +/** + * irq_gc_set_wake - Set/clr wake bit for an interrupt + * @d: irq_data + * + * For chips where the wake from suspend functionality is not + * configured in a separate register and the wakeup active state is + * just stored in a bitmask. + */ +int irq_gc_set_wake(struct irq_data *d, unsigned int on) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + u32 mask = 1 << (d->irq - gc->irq_base); + + if (!(mask & gc->wake_enabled)) + return -EINVAL; + + irq_gc_lock(gc); + if (on) + gc->wake_active |= mask; + else + gc->wake_active &= ~mask; + irq_gc_unlock(gc); + return 0; +} + +/** + * irq_alloc_generic_chip - Allocate a generic chip and initialize it + * @name: Name of the irq chip + * @num_ct: Number of irq_chip_type instances associated with this + * @irq_base: Interrupt base nr for this chip + * @reg_base: Register base address (virtual) + * @handler: Default flow handler associated with this chip + * + * Returns an initialized irq_chip_generic structure. The chip defaults + * to the primary (index 0) irq_chip_type and @handler + */ +struct irq_chip_generic * +irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base, + void __iomem *reg_base, irq_flow_handler_t handler) +{ + struct irq_chip_generic *gc; + unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type); + + gc = kzalloc(sz, GFP_KERNEL); + if (gc) { + raw_spin_lock_init(&gc->lock); + gc->num_ct = num_ct; + gc->irq_base = irq_base; + gc->reg_base = reg_base; + gc->chip_types->chip.name = name; + gc->chip_types->handler = handler; + } + return gc; +} + +/* + * Separate lockdep class for interrupt chip which can nest irq_desc + * lock. + */ +static struct lock_class_key irq_nested_lock_class; + +/** + * irq_setup_generic_chip - Setup a range of interrupts with a generic chip + * @gc: Generic irq chip holding all data + * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base + * @flags: Flags for initialization + * @clr: IRQ_* bits to clear + * @set: IRQ_* bits to set + * + * Set up max. 32 interrupts starting from gc->irq_base. Note, this + * initializes all interrupts to the primary irq_chip_type and its + * associated handler. + */ +void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk, + enum irq_gc_flags flags, unsigned int clr, + unsigned int set) +{ + struct irq_chip_type *ct = gc->chip_types; + unsigned int i; + + raw_spin_lock(&gc_lock); + list_add_tail(&gc->list, &gc_list); + raw_spin_unlock(&gc_lock); + + /* Init mask cache ? */ + if (flags & IRQ_GC_INIT_MASK_CACHE) + gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask); + + for (i = gc->irq_base; msk; msk >>= 1, i++) { + if (!msk & 0x01) + continue; + + if (flags & IRQ_GC_INIT_NESTED_LOCK) + irq_set_lockdep_class(i, &irq_nested_lock_class); + + irq_set_chip_and_handler(i, &ct->chip, ct->handler); + irq_set_chip_data(i, gc); + irq_modify_status(i, clr, set); + } + gc->irq_cnt = i - gc->irq_base; +} + +/** + * irq_setup_alt_chip - Switch to alternative chip + * @d: irq_data for this interrupt + * @type Flow type to be initialized + * + * Only to be called from chip->irq_set_type() callbacks. + */ +int irq_setup_alt_chip(struct irq_data *d, unsigned int type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = gc->chip_types; + unsigned int i; + + for (i = 0; i < gc->num_ct; i++, ct++) { + if (ct->type & type) { + d->chip = &ct->chip; + irq_data_to_desc(d)->handle_irq = ct->handler; + return 0; + } + } + return -EINVAL; +} + +/** + * irq_remove_generic_chip - Remove a chip + * @gc: Generic irq chip holding all data + * @msk: Bitmask holding the irqs to initialize relative to gc->irq_base + * @clr: IRQ_* bits to clear + * @set: IRQ_* bits to set + * + * Remove up to 32 interrupts starting from gc->irq_base. + */ +void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk, + unsigned int clr, unsigned int set) +{ + unsigned int i = gc->irq_base; + + raw_spin_lock(&gc_lock); + list_del(&gc->list); + raw_spin_unlock(&gc_lock); + + for (; msk; msk >>= 1, i++) { + if (!msk & 0x01) + continue; + + /* Remove handler first. That will mask the irq line */ + irq_set_handler(i, NULL); + irq_set_chip(i, &no_irq_chip); + irq_set_chip_data(i, NULL); + irq_modify_status(i, clr, set); + } +} + +#ifdef CONFIG_PM +static int irq_gc_suspend(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_suspend) + ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base)); + } + return 0; +} + +static void irq_gc_resume(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_resume) + ct->chip.irq_resume(irq_get_irq_data(gc->irq_base)); + } +} +#else +#define irq_gc_suspend NULL +#define irq_gc_resume NULL +#endif + +static void irq_gc_shutdown(void) +{ + struct irq_chip_generic *gc; + + list_for_each_entry(gc, &gc_list, list) { + struct irq_chip_type *ct = gc->chip_types; + + if (ct->chip.irq_pm_shutdown) + ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base)); + } +} + +static struct syscore_ops irq_gc_syscore_ops = { + .suspend = irq_gc_suspend, + .resume = irq_gc_resume, + .shutdown = irq_gc_shutdown, +}; + +static int __init irq_gc_init_ops(void) +{ + register_syscore_ops(&irq_gc_syscore_ops); + return 0; +} +device_initcall(irq_gc_init_ops); diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index e2347eb6330..90cb55f6d7e 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -51,30 +51,92 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action) "but no thread function available.", irq, action->name); } -/** - * handle_IRQ_event - irq action chain handler - * @irq: the interrupt number - * @action: the interrupt action chain for this irq - * - * Handles the action chain of an irq event - */ -irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action) +static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action) +{ + /* + * Wake up the handler thread for this action. In case the + * thread crashed and was killed we just pretend that we + * handled the interrupt. The hardirq handler has disabled the + * device interrupt, so no irq storm is lurking. If the + * RUNTHREAD bit is already set, nothing to do. + */ + if (test_bit(IRQTF_DIED, &action->thread_flags) || + test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) + return; + + /* + * It's safe to OR the mask lockless here. We have only two + * places which write to threads_oneshot: This code and the + * irq thread. + * + * This code is the hard irq context and can never run on two + * cpus in parallel. If it ever does we have more serious + * problems than this bitmask. + * + * The irq threads of this irq which clear their "running" bit + * in threads_oneshot are serialized via desc->lock against + * each other and they are serialized against this code by + * IRQS_INPROGRESS. + * + * Hard irq handler: + * + * spin_lock(desc->lock); + * desc->state |= IRQS_INPROGRESS; + * spin_unlock(desc->lock); + * set_bit(IRQTF_RUNTHREAD, &action->thread_flags); + * desc->threads_oneshot |= mask; + * spin_lock(desc->lock); + * desc->state &= ~IRQS_INPROGRESS; + * spin_unlock(desc->lock); + * + * irq thread: + * + * again: + * spin_lock(desc->lock); + * if (desc->state & IRQS_INPROGRESS) { + * spin_unlock(desc->lock); + * while(desc->state & IRQS_INPROGRESS) + * cpu_relax(); + * goto again; + * } + * if (!test_bit(IRQTF_RUNTHREAD, &action->thread_flags)) + * desc->threads_oneshot &= ~mask; + * spin_unlock(desc->lock); + * + * So either the thread waits for us to clear IRQS_INPROGRESS + * or we are waiting in the flow handler for desc->lock to be + * released before we reach this point. The thread also checks + * IRQTF_RUNTHREAD under desc->lock. If set it leaves + * threads_oneshot untouched and runs the thread another time. + */ + desc->threads_oneshot |= action->thread_mask; + wake_up_process(action->thread); +} + +irqreturn_t +handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) { - irqreturn_t ret, retval = IRQ_NONE; - unsigned int status = 0; + irqreturn_t retval = IRQ_NONE; + unsigned int random = 0, irq = desc->irq_data.irq; do { + irqreturn_t res; + trace_irq_handler_entry(irq, action); - ret = action->handler(irq, action->dev_id); - trace_irq_handler_exit(irq, action, ret); + res = action->handler(irq, action->dev_id); + trace_irq_handler_exit(irq, action, res); + + if (WARN_ONCE(!irqs_disabled(),"irq %u handler %pF enabled interrupts\n", + irq, action->handler)) + local_irq_disable(); - switch (ret) { + switch (res) { case IRQ_WAKE_THREAD: /* * Set result to handled so the spurious check * does not trigger. */ - ret = IRQ_HANDLED; + res = IRQ_HANDLED; /* * Catch drivers which return WAKE_THREAD but @@ -85,147 +147,41 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action) break; } - /* - * Wake up the handler thread for this - * action. In case the thread crashed and was - * killed we just pretend that we handled the - * interrupt. The hardirq handler above has - * disabled the device interrupt, so no irq - * storm is lurking. - */ - if (likely(!test_bit(IRQTF_DIED, - &action->thread_flags))) { - set_bit(IRQTF_RUNTHREAD, &action->thread_flags); - wake_up_process(action->thread); - } + irq_wake_thread(desc, action); /* Fall through to add to randomness */ case IRQ_HANDLED: - status |= action->flags; + random |= action->flags; break; default: break; } - retval |= ret; + retval |= res; action = action->next; } while (action); - if (status & IRQF_SAMPLE_RANDOM) + if (random & IRQF_SAMPLE_RANDOM) add_interrupt_randomness(irq); - local_irq_disable(); + if (!noirqdebug) + note_interrupt(irq, desc, retval); return retval; } -#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ - -#ifdef CONFIG_ENABLE_WARN_DEPRECATED -# warning __do_IRQ is deprecated. Please convert to proper flow handlers -#endif - -/** - * __do_IRQ - original all in one highlevel IRQ handler - * @irq: the interrupt number - * - * __do_IRQ handles all normal device IRQ's (the special - * SMP cross-CPU interrupts have their own specific - * handlers). - * - * This is the original x86 implementation which is used for every - * interrupt type. - */ -unsigned int __do_IRQ(unsigned int irq) +irqreturn_t handle_irq_event(struct irq_desc *desc) { - struct irq_desc *desc = irq_to_desc(irq); - struct irqaction *action; - unsigned int status; + struct irqaction *action = desc->action; + irqreturn_t ret; - kstat_incr_irqs_this_cpu(irq, desc); + desc->istate &= ~IRQS_PENDING; + irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); + raw_spin_unlock(&desc->lock); - if (CHECK_IRQ_PER_CPU(desc->status)) { - irqreturn_t action_ret; - - /* - * No locking required for CPU-local interrupts: - */ - if (desc->irq_data.chip->ack) - desc->irq_data.chip->ack(irq); - if (likely(!(desc->status & IRQ_DISABLED))) { - action_ret = handle_IRQ_event(irq, desc->action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - } - desc->irq_data.chip->end(irq); - return 1; - } + ret = handle_irq_event_percpu(desc, action); raw_spin_lock(&desc->lock); - if (desc->irq_data.chip->ack) - desc->irq_data.chip->ack(irq); - /* - * REPLAY is when Linux resends an IRQ that was dropped earlier - * WAITING is used by probe to mark irqs that are being tested - */ - status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); - status |= IRQ_PENDING; /* we _want_ to handle it */ - - /* - * If the IRQ is disabled for whatever reason, we cannot - * use the action we have. - */ - action = NULL; - if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) { - action = desc->action; - status &= ~IRQ_PENDING; /* we commit to handling */ - status |= IRQ_INPROGRESS; /* we are handling it */ - } - desc->status = status; - - /* - * If there is no IRQ handler or it was disabled, exit early. - * Since we set PENDING, if another processor is handling - * a different instance of this same irq, the other processor - * will take care of it. - */ - if (unlikely(!action)) - goto out; - - /* - * Edge triggered interrupts need to remember - * pending events. - * This applies to any hw interrupts that allow a second - * instance of the same irq to arrive while we are in do_IRQ - * or in the handler. But the code here only handles the _second_ - * instance of the irq, not the third or fourth. So it is mostly - * useful for irq hardware that does not mask cleanly in an - * SMP environment. - */ - for (;;) { - irqreturn_t action_ret; - - raw_spin_unlock(&desc->lock); - - action_ret = handle_IRQ_event(irq, action); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - - raw_spin_lock(&desc->lock); - if (likely(!(desc->status & IRQ_PENDING))) - break; - desc->status &= ~IRQ_PENDING; - } - desc->status &= ~IRQ_INPROGRESS; - -out: - /* - * The ->end() handler has to deal with interrupts which got - * disabled while the handler was running. - */ - desc->irq_data.chip->end(irq); - raw_spin_unlock(&desc->lock); - - return 1; + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); + return ret; } -#endif diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 4571ae7e085..6546431447d 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -1,27 +1,87 @@ /* * IRQ subsystem internal functions and variables: + * + * Do not ever include this file from anything else than + * kernel/irq/. Do not even think about using any information outside + * of this file for your non core code. */ #include <linux/irqdesc.h> +#ifdef CONFIG_SPARSE_IRQ +# define IRQ_BITMAP_BITS (NR_IRQS + 8196) +#else +# define IRQ_BITMAP_BITS NR_IRQS +#endif + +#define istate core_internal_state__do_not_mess_with_it + extern int noirqdebug; -#define irq_data_to_desc(data) container_of(data, struct irq_desc, irq_data) +/* + * Bits used by threaded handlers: + * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run + * IRQTF_DIED - handler thread died + * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed + * IRQTF_AFFINITY - irq thread is requested to adjust affinity + * IRQTF_FORCED_THREAD - irq action is force threaded + */ +enum { + IRQTF_RUNTHREAD, + IRQTF_DIED, + IRQTF_WARNED, + IRQTF_AFFINITY, + IRQTF_FORCED_THREAD, +}; -/* Set default functions for irq_chip structures: */ -extern void irq_chip_set_defaults(struct irq_chip *chip); +/* + * Bit masks for desc->state + * + * IRQS_AUTODETECT - autodetection in progress + * IRQS_SPURIOUS_DISABLED - was disabled due to spurious interrupt + * detection + * IRQS_POLL_INPROGRESS - polling in progress + * IRQS_ONESHOT - irq is not unmasked in primary handler + * IRQS_REPLAY - irq is replayed + * IRQS_WAITING - irq is waiting + * IRQS_PENDING - irq is pending and replayed later + * IRQS_SUSPENDED - irq is suspended + */ +enum { + IRQS_AUTODETECT = 0x00000001, + IRQS_SPURIOUS_DISABLED = 0x00000002, + IRQS_POLL_INPROGRESS = 0x00000008, + IRQS_ONESHOT = 0x00000020, + IRQS_REPLAY = 0x00000040, + IRQS_WAITING = 0x00000080, + IRQS_PENDING = 0x00000200, + IRQS_SUSPENDED = 0x00000800, +}; + +#include "debug.h" +#include "settings.h" -/* Set default handler: */ -extern void compat_irq_chip_set_default_handler(struct irq_desc *desc); +#define irq_data_to_desc(data) container_of(data, struct irq_desc, irq_data) extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, unsigned long flags); extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp); extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume); +extern int irq_startup(struct irq_desc *desc); +extern void irq_shutdown(struct irq_desc *desc); +extern void irq_enable(struct irq_desc *desc); +extern void irq_disable(struct irq_desc *desc); +extern void mask_irq(struct irq_desc *desc); +extern void unmask_irq(struct irq_desc *desc); + extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr); +irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action); +irqreturn_t handle_irq_event(struct irq_desc *desc); + /* Resending of interrupts :*/ void check_irq_resend(struct irq_desc *desc, unsigned int irq); +bool irq_wait_for_poll(struct irq_desc *desc); #ifdef CONFIG_PROC_FS extern void register_irq_proc(unsigned int irq, struct irq_desc *desc); @@ -37,20 +97,10 @@ static inline void unregister_handler_proc(unsigned int irq, struct irqaction *action) { } #endif -extern int irq_select_affinity_usr(unsigned int irq); +extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask); extern void irq_set_thread_affinity(struct irq_desc *desc); -#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED -static inline void irq_end(unsigned int irq, struct irq_desc *desc) -{ - if (desc->irq_data.chip && desc->irq_data.chip->end) - desc->irq_data.chip->end(irq); -} -#else -static inline void irq_end(unsigned int irq, struct irq_desc *desc) { } -#endif - /* Inline functions for support of irq chips on slow busses */ static inline void chip_bus_lock(struct irq_desc *desc) { @@ -64,43 +114,58 @@ static inline void chip_bus_sync_unlock(struct irq_desc *desc) desc->irq_data.chip->irq_bus_sync_unlock(&desc->irq_data); } +struct irq_desc * +__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus); +void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus); + +static inline struct irq_desc * +irq_get_desc_buslock(unsigned int irq, unsigned long *flags) +{ + return __irq_get_desc_lock(irq, flags, true); +} + +static inline void +irq_put_desc_busunlock(struct irq_desc *desc, unsigned long flags) +{ + __irq_put_desc_unlock(desc, flags, true); +} + +static inline struct irq_desc * +irq_get_desc_lock(unsigned int irq, unsigned long *flags) +{ + return __irq_get_desc_lock(irq, flags, false); +} + +static inline void +irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags) +{ + __irq_put_desc_unlock(desc, flags, false); +} + /* - * Debugging printout: + * Manipulation functions for irq_data.state */ +static inline void irqd_set_move_pending(struct irq_data *d) +{ + d->state_use_accessors |= IRQD_SETAFFINITY_PENDING; +} -#include <linux/kallsyms.h> - -#define P(f) if (desc->status & f) printk("%14s set\n", #f) +static inline void irqd_clr_move_pending(struct irq_data *d) +{ + d->state_use_accessors &= ~IRQD_SETAFFINITY_PENDING; +} -static inline void print_irq_desc(unsigned int irq, struct irq_desc *desc) +static inline void irqd_clear(struct irq_data *d, unsigned int mask) { - printk("irq %d, desc: %p, depth: %d, count: %d, unhandled: %d\n", - irq, desc, desc->depth, desc->irq_count, desc->irqs_unhandled); - printk("->handle_irq(): %p, ", desc->handle_irq); - print_symbol("%s\n", (unsigned long)desc->handle_irq); - printk("->irq_data.chip(): %p, ", desc->irq_data.chip); - print_symbol("%s\n", (unsigned long)desc->irq_data.chip); - printk("->action(): %p\n", desc->action); - if (desc->action) { - printk("->action->handler(): %p, ", desc->action->handler); - print_symbol("%s\n", (unsigned long)desc->action->handler); - } - - P(IRQ_INPROGRESS); - P(IRQ_DISABLED); - P(IRQ_PENDING); - P(IRQ_REPLAY); - P(IRQ_AUTODETECT); - P(IRQ_WAITING); - P(IRQ_LEVEL); - P(IRQ_MASKED); -#ifdef CONFIG_IRQ_PER_CPU - P(IRQ_PER_CPU); -#endif - P(IRQ_NOPROBE); - P(IRQ_NOREQUEST); - P(IRQ_NOAUTOEN); + d->state_use_accessors &= ~mask; } -#undef P +static inline void irqd_set(struct irq_data *d, unsigned int mask) +{ + d->state_use_accessors |= mask; +} +static inline bool irqd_has_set(struct irq_data *d, unsigned int mask) +{ + return d->state_use_accessors & mask; +} diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 9988d03797f..886e80347b3 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -22,7 +22,7 @@ */ static struct lock_class_key irq_desc_lock_class; -#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS) +#if defined(CONFIG_SMP) static void __init init_irq_default_affinity(void) { alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); @@ -72,18 +72,22 @@ static inline int desc_node(struct irq_desc *desc) { return 0; } static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node) { + int cpu; + desc->irq_data.irq = irq; desc->irq_data.chip = &no_irq_chip; desc->irq_data.chip_data = NULL; desc->irq_data.handler_data = NULL; desc->irq_data.msi_desc = NULL; - desc->status = IRQ_DEFAULT_INIT_FLAGS; + irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS); + irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); desc->handle_irq = handle_bad_irq; desc->depth = 1; desc->irq_count = 0; desc->irqs_unhandled = 0; desc->name = NULL; - memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs))); + for_each_possible_cpu(cpu) + *per_cpu_ptr(desc->kstat_irqs, cpu) = 0; desc_smp_init(desc, node); } @@ -91,7 +95,7 @@ int nr_irqs = NR_IRQS; EXPORT_SYMBOL_GPL(nr_irqs); static DEFINE_MUTEX(sparse_irq_lock); -static DECLARE_BITMAP(allocated_irqs, NR_IRQS); +static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS); #ifdef CONFIG_SPARSE_IRQ @@ -133,8 +137,7 @@ static struct irq_desc *alloc_desc(int irq, int node) if (!desc) return NULL; /* allocate based on nr_cpu_ids */ - desc->kstat_irqs = kzalloc_node(nr_cpu_ids * sizeof(*desc->kstat_irqs), - gfp, node); + desc->kstat_irqs = alloc_percpu(unsigned int); if (!desc->kstat_irqs) goto err_desc; @@ -149,7 +152,7 @@ static struct irq_desc *alloc_desc(int irq, int node) return desc; err_kstat: - kfree(desc->kstat_irqs); + free_percpu(desc->kstat_irqs); err_desc: kfree(desc); return NULL; @@ -166,7 +169,7 @@ static void free_desc(unsigned int irq) mutex_unlock(&sparse_irq_lock); free_masks(desc); - kfree(desc->kstat_irqs); + free_percpu(desc->kstat_irqs); kfree(desc); } @@ -195,13 +198,12 @@ err: return -ENOMEM; } -struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node) +static int irq_expand_nr_irqs(unsigned int nr) { - int res = irq_alloc_descs(irq, irq, 1, node); - - if (res == -EEXIST || res == irq) - return irq_to_desc(irq); - return NULL; + if (nr > IRQ_BITMAP_BITS) + return -ENOMEM; + nr_irqs = nr; + return 0; } int __init early_irq_init(void) @@ -215,6 +217,15 @@ int __init early_irq_init(void) initcnt = arch_probe_nr_irqs(); printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt); + if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS)) + nr_irqs = IRQ_BITMAP_BITS; + + if (WARN_ON(initcnt > IRQ_BITMAP_BITS)) + initcnt = IRQ_BITMAP_BITS; + + if (initcnt > nr_irqs) + nr_irqs = initcnt; + for (i = 0; i < initcnt; i++) { desc = alloc_desc(i, node); set_bit(i, allocated_irqs); @@ -227,14 +238,12 @@ int __init early_irq_init(void) struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = { [0 ... NR_IRQS-1] = { - .status = IRQ_DEFAULT_INIT_FLAGS, .handle_irq = handle_bad_irq, .depth = 1, .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock), } }; -static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS]; int __init early_irq_init(void) { int count, i, node = first_online_node; @@ -250,7 +259,8 @@ int __init early_irq_init(void) for (i = 0; i < count; i++) { desc[i].irq_data.irq = i; desc[i].irq_data.chip = &no_irq_chip; - desc[i].kstat_irqs = kstat_irqs_all[i]; + desc[i].kstat_irqs = alloc_percpu(unsigned int); + irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS); alloc_masks(desc + i, GFP_KERNEL, node); desc_smp_init(desc + i, node); lockdep_set_class(&desc[i].lock, &irq_desc_lock_class); @@ -263,11 +273,6 @@ struct irq_desc *irq_to_desc(unsigned int irq) return (irq < NR_IRQS) ? irq_desc + irq : NULL; } -struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node) -{ - return irq_to_desc(irq); -} - static void free_desc(unsigned int irq) { dynamic_irq_cleanup(irq); @@ -277,8 +282,30 @@ static inline int alloc_descs(unsigned int start, unsigned int cnt, int node) { return start; } + +static int irq_expand_nr_irqs(unsigned int nr) +{ + return -ENOMEM; +} + #endif /* !CONFIG_SPARSE_IRQ */ +/** + * generic_handle_irq - Invoke the handler for a particular irq + * @irq: The irq number to handle + * + */ +int generic_handle_irq(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc) + return -EINVAL; + generic_handle_irq_desc(irq, desc); + return 0; +} +EXPORT_SYMBOL_GPL(generic_handle_irq); + /* Dynamic interrupt handling */ /** @@ -300,6 +327,7 @@ void irq_free_descs(unsigned int from, unsigned int cnt) bitmap_clear(allocated_irqs, from, cnt); mutex_unlock(&sparse_irq_lock); } +EXPORT_SYMBOL_GPL(irq_free_descs); /** * irq_alloc_descs - allocate and initialize a range of irq descriptors @@ -320,14 +348,17 @@ irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node) mutex_lock(&sparse_irq_lock); - start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0); + start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS, + from, cnt, 0); ret = -EEXIST; if (irq >=0 && start != irq) goto err; - ret = -ENOMEM; - if (start >= nr_irqs) - goto err; + if (start + cnt > nr_irqs) { + ret = irq_expand_nr_irqs(start + cnt); + if (ret) + goto err; + } bitmap_set(allocated_irqs, start, cnt); mutex_unlock(&sparse_irq_lock); @@ -337,6 +368,7 @@ err: mutex_unlock(&sparse_irq_lock); return ret; } +EXPORT_SYMBOL_GPL(irq_alloc_descs); /** * irq_reserve_irqs - mark irqs allocated @@ -374,6 +406,26 @@ unsigned int irq_get_next_irq(unsigned int offset) return find_next_bit(allocated_irqs, nr_irqs, offset); } +struct irq_desc * +__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (desc) { + if (bus) + chip_bus_lock(desc); + raw_spin_lock_irqsave(&desc->lock, *flags); + } + return desc; +} + +void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus) +{ + raw_spin_unlock_irqrestore(&desc->lock, flags); + if (bus) + chip_bus_sync_unlock(desc); +} + /** * dynamic_irq_cleanup - cleanup a dynamically allocated irq * @irq: irq number to initialize @@ -391,20 +443,20 @@ void dynamic_irq_cleanup(unsigned int irq) unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) { struct irq_desc *desc = irq_to_desc(irq); - return desc ? desc->kstat_irqs[cpu] : 0; + + return desc && desc->kstat_irqs ? + *per_cpu_ptr(desc->kstat_irqs, cpu) : 0; } -#ifdef CONFIG_GENERIC_HARDIRQS unsigned int kstat_irqs(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); int cpu; int sum = 0; - if (!desc) + if (!desc || !desc->kstat_irqs) return 0; for_each_possible_cpu(cpu) - sum += desc->kstat_irqs[cpu]; + sum += *per_cpu_ptr(desc->kstat_irqs, cpu); return sum; } -#endif /* CONFIG_GENERIC_HARDIRQS */ diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 644e8d5fa36..f7ce0021e1c 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -17,6 +17,17 @@ #include "internals.h" +#ifdef CONFIG_IRQ_FORCED_THREADING +__read_mostly bool force_irqthreads; + +static int __init setup_forced_irqthreads(char *arg) +{ + force_irqthreads = true; + return 0; +} +early_param("threadirqs", setup_forced_irqthreads); +#endif + /** * synchronize_irq - wait for pending IRQ handlers (on other CPUs) * @irq: interrupt number to wait for @@ -30,7 +41,7 @@ void synchronize_irq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); - unsigned int status; + bool inprogress; if (!desc) return; @@ -42,16 +53,16 @@ void synchronize_irq(unsigned int irq) * Wait until we're out of the critical section. This might * give the wrong answer due to the lack of memory barriers. */ - while (desc->status & IRQ_INPROGRESS) + while (irqd_irq_inprogress(&desc->irq_data)) cpu_relax(); /* Ok, that indicated we're done: double-check carefully. */ raw_spin_lock_irqsave(&desc->lock, flags); - status = desc->status; + inprogress = irqd_irq_inprogress(&desc->irq_data); raw_spin_unlock_irqrestore(&desc->lock, flags); /* Oops, that failed? */ - } while (status & IRQ_INPROGRESS); + } while (inprogress); /* * We made sure that no hardirq handler is running. Now verify @@ -73,8 +84,8 @@ int irq_can_set_affinity(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); - if (CHECK_IRQ_PER_CPU(desc->status) || !desc->irq_data.chip || - !desc->irq_data.chip->irq_set_affinity) + if (!desc || !irqd_can_balance(&desc->irq_data) || + !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) return 0; return 1; @@ -100,67 +111,180 @@ void irq_set_thread_affinity(struct irq_desc *desc) } } +#ifdef CONFIG_GENERIC_PENDING_IRQ +static inline bool irq_can_move_pcntxt(struct irq_data *data) +{ + return irqd_can_move_in_process_context(data); +} +static inline bool irq_move_pending(struct irq_data *data) +{ + return irqd_is_setaffinity_pending(data); +} +static inline void +irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) +{ + cpumask_copy(desc->pending_mask, mask); +} +static inline void +irq_get_pending(struct cpumask *mask, struct irq_desc *desc) +{ + cpumask_copy(mask, desc->pending_mask); +} +#else +static inline bool irq_can_move_pcntxt(struct irq_data *data) { return true; } +static inline bool irq_move_pending(struct irq_data *data) { return false; } +static inline void +irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) { } +static inline void +irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { } +#endif + +int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) +{ + struct irq_chip *chip = irq_data_get_irq_chip(data); + struct irq_desc *desc = irq_data_to_desc(data); + int ret = 0; + + if (!chip || !chip->irq_set_affinity) + return -EINVAL; + + if (irq_can_move_pcntxt(data)) { + ret = chip->irq_set_affinity(data, mask, false); + switch (ret) { + case IRQ_SET_MASK_OK: + cpumask_copy(data->affinity, mask); + case IRQ_SET_MASK_OK_NOCOPY: + irq_set_thread_affinity(desc); + ret = 0; + } + } else { + irqd_set_move_pending(data); + irq_copy_pending(desc, mask); + } + + if (desc->affinity_notify) { + kref_get(&desc->affinity_notify->kref); + schedule_work(&desc->affinity_notify->work); + } + irqd_set(data, IRQD_AFFINITY_SET); + + return ret; +} + /** * irq_set_affinity - Set the irq affinity of a given irq * @irq: Interrupt to set affinity - * @cpumask: cpumask + * @mask: cpumask * */ -int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) +int irq_set_affinity(unsigned int irq, const struct cpumask *mask) { struct irq_desc *desc = irq_to_desc(irq); - struct irq_chip *chip = desc->irq_data.chip; unsigned long flags; + int ret; - if (!chip->irq_set_affinity) + if (!desc) return -EINVAL; raw_spin_lock_irqsave(&desc->lock, flags); - -#ifdef CONFIG_GENERIC_PENDING_IRQ - if (desc->status & IRQ_MOVE_PCNTXT) { - if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) { - cpumask_copy(desc->irq_data.affinity, cpumask); - irq_set_thread_affinity(desc); - } - } - else { - desc->status |= IRQ_MOVE_PENDING; - cpumask_copy(desc->pending_mask, cpumask); - } -#else - if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) { - cpumask_copy(desc->irq_data.affinity, cpumask); - irq_set_thread_affinity(desc); - } -#endif - desc->status |= IRQ_AFFINITY_SET; + ret = __irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask); raw_spin_unlock_irqrestore(&desc->lock, flags); - return 0; + return ret; } int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) { + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + + if (!desc) + return -EINVAL; + desc->affinity_hint = m; + irq_put_desc_unlock(desc, flags); + return 0; +} +EXPORT_SYMBOL_GPL(irq_set_affinity_hint); + +static void irq_affinity_notify(struct work_struct *work) +{ + struct irq_affinity_notify *notify = + container_of(work, struct irq_affinity_notify, work); + struct irq_desc *desc = irq_to_desc(notify->irq); + cpumask_var_t cpumask; + unsigned long flags; + + if (!desc || !alloc_cpumask_var(&cpumask, GFP_KERNEL)) + goto out; + + raw_spin_lock_irqsave(&desc->lock, flags); + if (irq_move_pending(&desc->irq_data)) + irq_get_pending(cpumask, desc); + else + cpumask_copy(cpumask, desc->irq_data.affinity); + raw_spin_unlock_irqrestore(&desc->lock, flags); + + notify->notify(notify, cpumask); + + free_cpumask_var(cpumask); +out: + kref_put(¬ify->kref, notify->release); +} + +/** + * irq_set_affinity_notifier - control notification of IRQ affinity changes + * @irq: Interrupt for which to enable/disable notification + * @notify: Context for notification, or %NULL to disable + * notification. Function pointers must be initialised; + * the other fields will be initialised by this function. + * + * Must be called in process context. Notification may only be enabled + * after the IRQ is allocated and must be disabled before the IRQ is + * freed using free_irq(). + */ +int +irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) +{ struct irq_desc *desc = irq_to_desc(irq); + struct irq_affinity_notify *old_notify; unsigned long flags; + /* The release function is promised process context */ + might_sleep(); + if (!desc) return -EINVAL; + /* Complete initialisation of *notify */ + if (notify) { + notify->irq = irq; + kref_init(¬ify->kref); + INIT_WORK(¬ify->work, irq_affinity_notify); + } + raw_spin_lock_irqsave(&desc->lock, flags); - desc->affinity_hint = m; + old_notify = desc->affinity_notify; + desc->affinity_notify = notify; raw_spin_unlock_irqrestore(&desc->lock, flags); + if (old_notify) + kref_put(&old_notify->kref, old_notify->release); + return 0; } -EXPORT_SYMBOL_GPL(irq_set_affinity_hint); +EXPORT_SYMBOL_GPL(irq_set_affinity_notifier); #ifndef CONFIG_AUTO_IRQ_AFFINITY /* * Generic version of the affinity autoselector. */ -static int setup_affinity(unsigned int irq, struct irq_desc *desc) +static int +setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) { + struct irq_chip *chip = irq_desc_get_chip(desc); + struct cpumask *set = irq_default_affinity; + int ret; + + /* Excludes PER_CPU and NO_BALANCE interrupts */ if (!irq_can_set_affinity(irq)) return 0; @@ -168,22 +292,27 @@ static int setup_affinity(unsigned int irq, struct irq_desc *desc) * Preserve an userspace affinity setup, but make sure that * one of the targets is online. */ - if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) { - if (cpumask_any_and(desc->irq_data.affinity, cpu_online_mask) - < nr_cpu_ids) - goto set_affinity; + if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) { + if (cpumask_intersects(desc->irq_data.affinity, + cpu_online_mask)) + set = desc->irq_data.affinity; else - desc->status &= ~IRQ_AFFINITY_SET; + irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET); } - cpumask_and(desc->irq_data.affinity, cpu_online_mask, irq_default_affinity); -set_affinity: - desc->irq_data.chip->irq_set_affinity(&desc->irq_data, desc->irq_data.affinity, false); - + cpumask_and(mask, cpu_online_mask, set); + ret = chip->irq_set_affinity(&desc->irq_data, mask, false); + switch (ret) { + case IRQ_SET_MASK_OK: + cpumask_copy(desc->irq_data.affinity, mask); + case IRQ_SET_MASK_OK_NOCOPY: + irq_set_thread_affinity(desc); + } return 0; } #else -static inline int setup_affinity(unsigned int irq, struct irq_desc *d) +static inline int +setup_affinity(unsigned int irq, struct irq_desc *d, struct cpumask *mask) { return irq_select_affinity(irq); } @@ -192,23 +321,21 @@ static inline int setup_affinity(unsigned int irq, struct irq_desc *d) /* * Called when affinity is set via /proc/irq */ -int irq_select_affinity_usr(unsigned int irq) +int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; int ret; raw_spin_lock_irqsave(&desc->lock, flags); - ret = setup_affinity(irq, desc); - if (!ret) - irq_set_thread_affinity(desc); + ret = setup_affinity(irq, desc, mask); raw_spin_unlock_irqrestore(&desc->lock, flags); - return ret; } #else -static inline int setup_affinity(unsigned int irq, struct irq_desc *desc) +static inline int +setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask) { return 0; } @@ -219,13 +346,23 @@ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend) if (suspend) { if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND)) return; - desc->status |= IRQ_SUSPENDED; + desc->istate |= IRQS_SUSPENDED; } - if (!desc->depth++) { - desc->status |= IRQ_DISABLED; - desc->irq_data.chip->irq_disable(&desc->irq_data); - } + if (!desc->depth++) + irq_disable(desc); +} + +static int __disable_irq_nosync(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); + + if (!desc) + return -EINVAL; + __disable_irq(desc, irq, false); + irq_put_desc_busunlock(desc, flags); + return 0; } /** @@ -241,17 +378,7 @@ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend) */ void disable_irq_nosync(unsigned int irq) { - struct irq_desc *desc = irq_to_desc(irq); - unsigned long flags; - - if (!desc) - return; - - chip_bus_lock(desc); - raw_spin_lock_irqsave(&desc->lock, flags); - __disable_irq(desc, irq, false); - raw_spin_unlock_irqrestore(&desc->lock, flags); - chip_bus_sync_unlock(desc); + __disable_irq_nosync(irq); } EXPORT_SYMBOL(disable_irq_nosync); @@ -269,21 +396,24 @@ EXPORT_SYMBOL(disable_irq_nosync); */ void disable_irq(unsigned int irq) { - struct irq_desc *desc = irq_to_desc(irq); - - if (!desc) - return; - - disable_irq_nosync(irq); - if (desc->action) + if (!__disable_irq_nosync(irq)) synchronize_irq(irq); } EXPORT_SYMBOL(disable_irq); void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) { - if (resume) - desc->status &= ~IRQ_SUSPENDED; + if (resume) { + if (!(desc->istate & IRQS_SUSPENDED)) { + if (!desc->action) + return; + if (!(desc->action->flags & IRQF_FORCE_RESUME)) + return; + /* Pretend that it got disabled ! */ + desc->depth++; + } + desc->istate &= ~IRQS_SUSPENDED; + } switch (desc->depth) { case 0: @@ -291,12 +421,11 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq); break; case 1: { - unsigned int status = desc->status & ~IRQ_DISABLED; - - if (desc->status & IRQ_SUSPENDED) + if (desc->istate & IRQS_SUSPENDED) goto err_out; /* Prevent probing on this irq: */ - desc->status = status | IRQ_NOPROBE; + irq_settings_set_noprobe(desc); + irq_enable(desc); check_irq_resend(desc, irq); /* fall-through */ } @@ -318,17 +447,18 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) */ void enable_irq(unsigned int irq) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); if (!desc) return; + if (WARN(!desc->irq_data.chip, + KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq)) + goto out; - chip_bus_lock(desc); - raw_spin_lock_irqsave(&desc->lock, flags); __enable_irq(desc, irq, false); - raw_spin_unlock_irqrestore(&desc->lock, flags); - chip_bus_sync_unlock(desc); +out: + irq_put_desc_busunlock(desc, flags); } EXPORT_SYMBOL(enable_irq); @@ -344,7 +474,7 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on) } /** - * set_irq_wake - control irq power management wakeup + * irq_set_irq_wake - control irq power management wakeup * @irq: interrupt to control * @on: enable/disable power management wakeup * @@ -355,23 +485,22 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on) * Wakeup mode lets this IRQ wake the system from sleep * states like "suspend to RAM". */ -int set_irq_wake(unsigned int irq, unsigned int on) +int irq_set_irq_wake(unsigned int irq, unsigned int on) { - struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; + struct irq_desc *desc = irq_get_desc_buslock(irq, &flags); int ret = 0; /* wakeup-capable irqs can be shared between drivers that * don't need to have the same sleep mode behaviors. */ - raw_spin_lock_irqsave(&desc->lock, flags); if (on) { if (desc->wake_depth++ == 0) { ret = set_irq_wake_real(irq, on); if (ret) desc->wake_depth = 0; else - desc->status |= IRQ_WAKEUP; + irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE); } } else { if (desc->wake_depth == 0) { @@ -381,14 +510,13 @@ int set_irq_wake(unsigned int irq, unsigned int on) if (ret) desc->wake_depth = 1; else - desc->status &= ~IRQ_WAKEUP; + irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE); } } - - raw_spin_unlock_irqrestore(&desc->lock, flags); + irq_put_desc_busunlock(desc, flags); return ret; } -EXPORT_SYMBOL(set_irq_wake); +EXPORT_SYMBOL(irq_set_irq_wake); /* * Internal function that tells the architecture code whether a @@ -397,43 +525,27 @@ EXPORT_SYMBOL(set_irq_wake); */ int can_request_irq(unsigned int irq, unsigned long irqflags) { - struct irq_desc *desc = irq_to_desc(irq); - struct irqaction *action; unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags); + int canrequest = 0; if (!desc) return 0; - if (desc->status & IRQ_NOREQUEST) - return 0; - - raw_spin_lock_irqsave(&desc->lock, flags); - action = desc->action; - if (action) - if (irqflags & action->flags & IRQF_SHARED) - action = NULL; - - raw_spin_unlock_irqrestore(&desc->lock, flags); - - return !action; -} - -void compat_irq_chip_set_default_handler(struct irq_desc *desc) -{ - /* - * If the architecture still has not overriden - * the flow handler then zap the default. This - * should catch incorrect flow-type setting. - */ - if (desc->handle_irq == &handle_bad_irq) - desc->handle_irq = NULL; + if (irq_settings_can_request(desc)) { + if (desc->action) + if (irqflags & desc->action->flags & IRQF_SHARED) + canrequest =1; + } + irq_put_desc_unlock(desc, flags); + return canrequest; } int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, unsigned long flags) { - int ret; struct irq_chip *chip = desc->irq_data.chip; + int ret, unmask = 0; if (!chip || !chip->irq_set_type) { /* @@ -445,23 +557,41 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, return 0; } + flags &= IRQ_TYPE_SENSE_MASK; + + if (chip->flags & IRQCHIP_SET_TYPE_MASKED) { + if (!irqd_irq_masked(&desc->irq_data)) + mask_irq(desc); + if (!irqd_irq_disabled(&desc->irq_data)) + unmask = 1; + } + /* caller masked out all except trigger mode flags */ ret = chip->irq_set_type(&desc->irq_data, flags); - if (ret) + switch (ret) { + case IRQ_SET_MASK_OK: + irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK); + irqd_set(&desc->irq_data, flags); + + case IRQ_SET_MASK_OK_NOCOPY: + flags = irqd_get_trigger_type(&desc->irq_data); + irq_settings_set_trigger_mask(desc, flags); + irqd_clear(&desc->irq_data, IRQD_LEVEL); + irq_settings_clr_level(desc); + if (flags & IRQ_TYPE_LEVEL_MASK) { + irq_settings_set_level(desc); + irqd_set(&desc->irq_data, IRQD_LEVEL); + } + + ret = 0; + break; + default: pr_err("setting trigger mode %lu for irq %u failed (%pF)\n", flags, irq, chip->irq_set_type); - else { - if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) - flags |= IRQ_LEVEL; - /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */ - desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK); - desc->status |= flags; - - if (chip != desc->irq_data.chip) - irq_chip_set_defaults(desc->irq_data.chip); } - + if (unmask) + unmask_irq(desc); return ret; } @@ -505,8 +635,11 @@ static int irq_wait_for_interrupt(struct irqaction *action) * handler finished. unmask if the interrupt has not been disabled and * is marked MASKED. */ -static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc) +static void irq_finalize_oneshot(struct irq_desc *desc, + struct irqaction *action, bool force) { + if (!(desc->istate & IRQS_ONESHOT)) + return; again: chip_bus_lock(desc); raw_spin_lock_irq(&desc->lock); @@ -518,26 +651,42 @@ again: * The thread is faster done than the hard interrupt handler * on the other CPU. If we unmask the irq line then the * interrupt can come in again and masks the line, leaves due - * to IRQ_INPROGRESS and the irq line is masked forever. + * to IRQS_INPROGRESS and the irq line is masked forever. + * + * This also serializes the state of shared oneshot handlers + * versus "desc->threads_onehsot |= action->thread_mask;" in + * irq_wake_thread(). See the comment there which explains the + * serialization. */ - if (unlikely(desc->status & IRQ_INPROGRESS)) { + if (unlikely(irqd_irq_inprogress(&desc->irq_data))) { raw_spin_unlock_irq(&desc->lock); chip_bus_sync_unlock(desc); cpu_relax(); goto again; } - if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) { - desc->status &= ~IRQ_MASKED; - desc->irq_data.chip->irq_unmask(&desc->irq_data); - } + /* + * Now check again, whether the thread should run. Otherwise + * we would clear the threads_oneshot bit of this thread which + * was just set. + */ + if (!force && test_bit(IRQTF_RUNTHREAD, &action->thread_flags)) + goto out_unlock; + + desc->threads_oneshot &= ~action->thread_mask; + + if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data)) + unmask_irq(desc); + +out_unlock: raw_spin_unlock_irq(&desc->lock); chip_bus_sync_unlock(desc); } #ifdef CONFIG_SMP /* - * Check whether we need to change the affinity of the interrupt thread. + * Check whether we need to chasnge the affinity of the interrupt thread. */ static void irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) @@ -569,14 +718,49 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { } #endif /* + * Interrupts which are not explicitely requested as threaded + * interrupts rely on the implicit bh/preempt disable of the hard irq + * context. So we need to disable bh here to avoid deadlocks and other + * side effects. + */ +static void +irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action) +{ + local_bh_disable(); + action->thread_fn(action->irq, action->dev_id); + irq_finalize_oneshot(desc, action, false); + local_bh_enable(); +} + +/* + * Interrupts explicitely requested as threaded interupts want to be + * preemtible - many of them need to sleep and wait for slow busses to + * complete. + */ +static void irq_thread_fn(struct irq_desc *desc, struct irqaction *action) +{ + action->thread_fn(action->irq, action->dev_id); + irq_finalize_oneshot(desc, action, false); +} + +/* * Interrupt handler thread */ static int irq_thread(void *data) { - struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, }; + static const struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; struct irqaction *action = data; struct irq_desc *desc = irq_to_desc(action->irq); - int wake, oneshot = desc->status & IRQ_ONESHOT; + void (*handler_fn)(struct irq_desc *desc, struct irqaction *action); + int wake; + + if (force_irqthreads & test_bit(IRQTF_FORCED_THREAD, + &action->thread_flags)) + handler_fn = irq_forced_thread_fn; + else + handler_fn = irq_thread_fn; sched_setscheduler(current, SCHED_FIFO, ¶m); current->irqaction = action; @@ -588,23 +772,19 @@ static int irq_thread(void *data) atomic_inc(&desc->threads_active); raw_spin_lock_irq(&desc->lock); - if (unlikely(desc->status & IRQ_DISABLED)) { + if (unlikely(irqd_irq_disabled(&desc->irq_data))) { /* * CHECKME: We might need a dedicated * IRQ_THREAD_PENDING flag here, which * retriggers the thread in check_irq_resend() - * but AFAICT IRQ_PENDING should be fine as it + * but AFAICT IRQS_PENDING should be fine as it * retriggers the interrupt itself --- tglx */ - desc->status |= IRQ_PENDING; + desc->istate |= IRQS_PENDING; raw_spin_unlock_irq(&desc->lock); } else { raw_spin_unlock_irq(&desc->lock); - - action->thread_fn(action->irq, action->dev_id); - - if (oneshot) - irq_finalize_oneshot(action->irq, desc); + handler_fn(desc, action); } wake = atomic_dec_and_test(&desc->threads_active); @@ -613,6 +793,9 @@ static int irq_thread(void *data) wake_up(&desc->wait_for_threads); } + /* Prevent a stale desc->threads_oneshot */ + irq_finalize_oneshot(desc, action, true); + /* * Clear irqaction. Otherwise exit_irq_thread() would make * fuzz about an active irq thread going into nirvana. @@ -627,6 +810,7 @@ static int irq_thread(void *data) void exit_irq_thread(void) { struct task_struct *tsk = current; + struct irq_desc *desc; if (!tsk->irqaction) return; @@ -635,6 +819,14 @@ void exit_irq_thread(void) "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n", tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq); + desc = irq_to_desc(tsk->irqaction->irq); + + /* + * Prevent a stale desc->threads_oneshot. Must be called + * before setting the IRQTF_DIED flag. + */ + irq_finalize_oneshot(desc, tsk->irqaction, true); + /* * Set the THREAD DIED flag to prevent further wakeups of the * soon to be gone threaded handler. @@ -642,6 +834,22 @@ void exit_irq_thread(void) set_bit(IRQTF_DIED, &tsk->irqaction->flags); } +static void irq_setup_forced_threading(struct irqaction *new) +{ + if (!force_irqthreads) + return; + if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT)) + return; + + new->flags |= IRQF_ONESHOT; + + if (!new->thread_fn) { + set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); + new->thread_fn = new->handler; + new->handler = irq_default_primary_handler; + } +} + /* * Internal function to register an irqaction - typically used to * allocate special interrupts that are part of the architecture. @@ -651,9 +859,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) { struct irqaction *old, **old_ptr; const char *old_name = NULL; - unsigned long flags; - int nested, shared = 0; - int ret; + unsigned long flags, thread_mask = 0; + int ret, nested, shared = 0; + cpumask_var_t mask; if (!desc) return -EINVAL; @@ -677,15 +885,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) rand_initialize_irq(irq); } - /* Oneshot interrupts are not allowed with shared */ - if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED)) - return -EINVAL; - /* * Check whether the interrupt nests into another interrupt * thread. */ - nested = desc->status & IRQ_NESTED_THREAD; + nested = irq_settings_is_nested_thread(desc); if (nested) { if (!new->thread_fn) return -EINVAL; @@ -695,6 +899,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * dummy function which warns when called. */ new->handler = irq_nested_primary_handler; + } else { + if (irq_settings_can_thread(desc)) + irq_setup_forced_threading(new); } /* @@ -718,6 +925,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) new->thread = t; } + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { + ret = -ENOMEM; + goto out_thread; + } + /* * The following block of code has to be executed atomically */ @@ -729,32 +941,41 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * Can't share interrupts unless both agree to and are * the same type (level, edge, polarity). So both flag * fields must have IRQF_SHARED set and the bits which - * set the trigger type must match. + * set the trigger type must match. Also all must + * agree on ONESHOT. */ if (!((old->flags & new->flags) & IRQF_SHARED) || - ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) { + ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) || + ((old->flags ^ new->flags) & IRQF_ONESHOT)) { old_name = old->name; goto mismatch; } -#if defined(CONFIG_IRQ_PER_CPU) /* All handlers must agree on per-cpuness */ if ((old->flags & IRQF_PERCPU) != (new->flags & IRQF_PERCPU)) goto mismatch; -#endif /* add new interrupt at end of irq queue */ do { + thread_mask |= old->thread_mask; old_ptr = &old->next; old = *old_ptr; } while (old); shared = 1; } - if (!shared) { - irq_chip_set_defaults(desc->irq_data.chip); + /* + * Setup the thread mask for this irqaction. Unlikely to have + * 32 resp 64 irqs sharing one line, but who knows. + */ + if (new->flags & IRQF_ONESHOT && thread_mask == ~0UL) { + ret = -EBUSY; + goto out_mask; + } + new->thread_mask = 1 << ffz(thread_mask); + if (!shared) { init_waitqueue_head(&desc->wait_for_threads); /* Setup the type (level, edge polarity) if configured: */ @@ -763,42 +984,44 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) new->flags & IRQF_TRIGGER_MASK); if (ret) - goto out_thread; - } else - compat_irq_chip_set_default_handler(desc); -#if defined(CONFIG_IRQ_PER_CPU) - if (new->flags & IRQF_PERCPU) - desc->status |= IRQ_PER_CPU; -#endif + goto out_mask; + } + + desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \ + IRQS_ONESHOT | IRQS_WAITING); + irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); - desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT | - IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED); + if (new->flags & IRQF_PERCPU) { + irqd_set(&desc->irq_data, IRQD_PER_CPU); + irq_settings_set_per_cpu(desc); + } if (new->flags & IRQF_ONESHOT) - desc->status |= IRQ_ONESHOT; + desc->istate |= IRQS_ONESHOT; - if (!(desc->status & IRQ_NOAUTOEN)) { - desc->depth = 0; - desc->status &= ~IRQ_DISABLED; - desc->irq_data.chip->irq_startup(&desc->irq_data); - } else + if (irq_settings_can_autoenable(desc)) + irq_startup(desc); + else /* Undo nested disables: */ desc->depth = 1; /* Exclude IRQ from balancing if requested */ - if (new->flags & IRQF_NOBALANCING) - desc->status |= IRQ_NO_BALANCING; + if (new->flags & IRQF_NOBALANCING) { + irq_settings_set_no_balancing(desc); + irqd_set(&desc->irq_data, IRQD_NO_BALANCING); + } /* Set default affinity mask once everything is setup */ - setup_affinity(irq, desc); - - } else if ((new->flags & IRQF_TRIGGER_MASK) - && (new->flags & IRQF_TRIGGER_MASK) - != (desc->status & IRQ_TYPE_SENSE_MASK)) { - /* hope the handler works with the actual trigger mode... */ - pr_warning("IRQ %d uses trigger mode %d; requested %d\n", - irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK), - (int)(new->flags & IRQF_TRIGGER_MASK)); + setup_affinity(irq, desc, mask); + + } else if (new->flags & IRQF_TRIGGER_MASK) { + unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK; + unsigned int omsk = irq_settings_get_trigger_mask(desc); + + if (nmsk != omsk) + /* hope the handler works with current trigger mode */ + pr_warning("IRQ %d uses trigger mode %u; requested %u\n", + irq, nmsk, omsk); } new->irq = irq; @@ -812,8 +1035,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * Check whether we disabled the irq via the spurious handler * before. Reenable it and give it another chance. */ - if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) { - desc->status &= ~IRQ_SPURIOUS_DISABLED; + if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) { + desc->istate &= ~IRQS_SPURIOUS_DISABLED; __enable_irq(desc, irq, false); } @@ -829,6 +1052,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) register_irq_proc(irq, desc); new->dir = NULL; register_handler_proc(irq, new); + free_cpumask_var(mask); return 0; @@ -843,8 +1067,11 @@ mismatch: #endif ret = -EBUSY; -out_thread: +out_mask: raw_spin_unlock_irqrestore(&desc->lock, flags); + free_cpumask_var(mask); + +out_thread: if (new->thread) { struct task_struct *t = new->thread; @@ -865,9 +1092,14 @@ out_thread: */ int setup_irq(unsigned int irq, struct irqaction *act) { + int retval; struct irq_desc *desc = irq_to_desc(irq); - return __setup_irq(irq, desc, act); + chip_bus_lock(desc); + retval = __setup_irq(irq, desc, act); + chip_bus_sync_unlock(desc); + + return retval; } EXPORT_SYMBOL_GPL(setup_irq); @@ -918,13 +1150,8 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) #endif /* If this was the last handler, shut down the IRQ line: */ - if (!desc->action) { - desc->status |= IRQ_DISABLED; - if (desc->irq_data.chip->irq_shutdown) - desc->irq_data.chip->irq_shutdown(&desc->irq_data); - else - desc->irq_data.chip->irq_disable(&desc->irq_data); - } + if (!desc->action) + irq_shutdown(desc); #ifdef CONFIG_SMP /* make sure affinity_hint is cleaned up */ @@ -998,6 +1225,11 @@ void free_irq(unsigned int irq, void *dev_id) if (!desc) return; +#ifdef CONFIG_SMP + if (WARN_ON(desc->affinity_notify)) + desc->affinity_notify = NULL; +#endif + chip_bus_lock(desc); kfree(__free_irq(irq, dev_id)); chip_bus_sync_unlock(desc); @@ -1068,7 +1300,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, if (!desc) return -EINVAL; - if (desc->status & IRQ_NOREQUEST) + if (!irq_settings_can_request(desc)) return -EINVAL; if (!handler) { @@ -1094,7 +1326,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, if (retval) kfree(action); -#ifdef CONFIG_DEBUG_SHIRQ +#ifdef CONFIG_DEBUG_SHIRQ_FIXME if (!retval && (irqflags & IRQF_SHARED)) { /* * It's a shared IRQ -- the driver ought to be prepared for it @@ -1143,7 +1375,7 @@ int request_any_context_irq(unsigned int irq, irq_handler_t handler, if (!desc) return -EINVAL; - if (desc->status & IRQ_NESTED_THREAD) { + if (irq_settings_is_nested_thread(desc)) { ret = request_threaded_irq(irq, NULL, handler, flags, name, dev_id); return !ret ? IRQC_IS_NESTED : ret; diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c index 1d254194048..47420908fba 100644 --- a/kernel/irq/migration.c +++ b/kernel/irq/migration.c @@ -4,23 +4,23 @@ #include "internals.h" -void move_masked_irq(int irq) +void irq_move_masked_irq(struct irq_data *idata) { - struct irq_desc *desc = irq_to_desc(irq); - struct irq_chip *chip = desc->irq_data.chip; + struct irq_desc *desc = irq_data_to_desc(idata); + struct irq_chip *chip = idata->chip; - if (likely(!(desc->status & IRQ_MOVE_PENDING))) + if (likely(!irqd_is_setaffinity_pending(&desc->irq_data))) return; /* * Paranoia: cpu-local interrupts shouldn't be calling in here anyway. */ - if (CHECK_IRQ_PER_CPU(desc->status)) { + if (!irqd_can_balance(&desc->irq_data)) { WARN_ON(1); return; } - desc->status &= ~IRQ_MOVE_PENDING; + irqd_clr_move_pending(&desc->irq_data); if (unlikely(cpumask_empty(desc->pending_mask))) return; @@ -35,7 +35,7 @@ void move_masked_irq(int irq) * do the disable, re-program, enable sequence. * This is *not* particularly important for level triggered * but in a edge trigger case, we might be setting rte - * when an active trigger is comming in. This could + * when an active trigger is coming in. This could * cause some ioapics to mal-function. * Being paranoid i guess! * @@ -53,18 +53,25 @@ void move_masked_irq(int irq) cpumask_clear(desc->pending_mask); } -void move_native_irq(int irq) +void irq_move_irq(struct irq_data *idata) { - struct irq_desc *desc = irq_to_desc(irq); + bool masked; - if (likely(!(desc->status & IRQ_MOVE_PENDING))) + if (likely(!irqd_is_setaffinity_pending(idata))) return; - if (unlikely(desc->status & IRQ_DISABLED)) + if (unlikely(irqd_irq_disabled(idata))) return; - desc->irq_data.chip->irq_mask(&desc->irq_data); - move_masked_irq(irq); - desc->irq_data.chip->irq_unmask(&desc->irq_data); + /* + * Be careful vs. already masked interrupts. If this is a + * threaded interrupt with ONESHOT set, we can end up with an + * interrupt storm. + */ + masked = irqd_irq_masked(idata); + if (!masked) + idata->chip->irq_mask(idata); + irq_move_masked_irq(idata); + if (!masked) + idata->chip->irq_unmask(idata); } - diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index 0d4005d85b0..f76fc00c987 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -18,7 +18,7 @@ * During system-wide suspend or hibernation device drivers need to be prevented * from receiving interrupts and this function is provided for this purpose. * It marks all interrupt lines in use, except for the timer ones, as disabled - * and sets the IRQ_SUSPENDED flag for each of them. + * and sets the IRQS_SUSPENDED flag for each of them. */ void suspend_device_irqs(void) { @@ -34,7 +34,7 @@ void suspend_device_irqs(void) } for_each_irq_desc(irq, desc) - if (desc->status & IRQ_SUSPENDED) + if (desc->istate & IRQS_SUSPENDED) synchronize_irq(irq); } EXPORT_SYMBOL_GPL(suspend_device_irqs); @@ -43,7 +43,7 @@ EXPORT_SYMBOL_GPL(suspend_device_irqs); * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() * * Enable all interrupt lines previously disabled by suspend_device_irqs() that - * have the IRQ_SUSPENDED flag set. + * have the IRQS_SUSPENDED flag set. */ void resume_device_irqs(void) { @@ -53,9 +53,6 @@ void resume_device_irqs(void) for_each_irq_desc(irq, desc) { unsigned long flags; - if (!(desc->status & IRQ_SUSPENDED)) - continue; - raw_spin_lock_irqsave(&desc->lock, flags); __enable_irq(desc, irq, true); raw_spin_unlock_irqrestore(&desc->lock, flags); @@ -71,9 +68,24 @@ int check_wakeup_irqs(void) struct irq_desc *desc; int irq; - for_each_irq_desc(irq, desc) - if ((desc->status & IRQ_WAKEUP) && (desc->status & IRQ_PENDING)) - return -EBUSY; + for_each_irq_desc(irq, desc) { + if (irqd_is_wakeup_set(&desc->irq_data)) { + if (desc->istate & IRQS_PENDING) + return -EBUSY; + continue; + } + /* + * Check the non wakeup interrupts whether they need + * to be masked before finally going into suspend + * state. That's for hardware which has no wakeup + * source configuration facility. The chip + * implementation indicates that with + * IRQCHIP_MASK_ON_SUSPEND. + */ + if (desc->istate & IRQS_SUSPENDED && + irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND) + mask_irq(desc); + } return 0; } diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 01b1d3a8898..834899f2500 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -11,6 +11,7 @@ #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/interrupt.h> +#include <linux/kernel_stat.h> #include "internals.h" @@ -24,7 +25,7 @@ static int irq_affinity_proc_show(struct seq_file *m, void *v) const struct cpumask *mask = desc->irq_data.affinity; #ifdef CONFIG_GENERIC_PENDING_IRQ - if (desc->status & IRQ_MOVE_PENDING) + if (irqd_is_setaffinity_pending(&desc->irq_data)) mask = desc->pending_mask; #endif seq_cpumask(m, mask); @@ -65,8 +66,7 @@ static ssize_t irq_affinity_proc_write(struct file *file, cpumask_var_t new_value; int err; - if (!irq_to_desc(irq)->irq_data.chip->irq_set_affinity || no_irq_affinity || - irq_balancing_disabled(irq)) + if (!irq_can_set_affinity(irq) || no_irq_affinity) return -EIO; if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) @@ -89,7 +89,7 @@ static ssize_t irq_affinity_proc_write(struct file *file, if (!cpumask_intersects(new_value, cpu_online_mask)) { /* Special case for empty set - allow the architecture code to set default SMP affinity. */ - err = irq_select_affinity_usr(irq) ? -EINVAL : count; + err = irq_select_affinity_usr(irq, new_value) ? -EINVAL : count; } else { irq_set_affinity(irq, new_value); err = count; @@ -214,7 +214,7 @@ static int irq_spurious_proc_show(struct seq_file *m, void *v) static int irq_spurious_proc_open(struct inode *inode, struct file *file) { - return single_open(file, irq_spurious_proc_show, NULL); + return single_open(file, irq_spurious_proc_show, PDE(inode)->data); } static const struct file_operations irq_spurious_proc_fops = { @@ -357,3 +357,83 @@ void init_irq_proc(void) } } +#ifdef CONFIG_GENERIC_IRQ_SHOW + +int __weak arch_show_interrupts(struct seq_file *p, int prec) +{ + return 0; +} + +#ifndef ACTUAL_NR_IRQS +# define ACTUAL_NR_IRQS nr_irqs +#endif + +int show_interrupts(struct seq_file *p, void *v) +{ + static int prec; + + unsigned long flags, any_count = 0; + int i = *(loff_t *) v, j; + struct irqaction *action; + struct irq_desc *desc; + + if (i > ACTUAL_NR_IRQS) + return 0; + + if (i == ACTUAL_NR_IRQS) + return arch_show_interrupts(p, prec); + + /* print header and calculate the width of the first column */ + if (i == 0) { + for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec) + j *= 10; + + seq_printf(p, "%*s", prec + 8, ""); + for_each_online_cpu(j) + seq_printf(p, "CPU%-8d", j); + seq_putc(p, '\n'); + } + + desc = irq_to_desc(i); + if (!desc) + return 0; + + raw_spin_lock_irqsave(&desc->lock, flags); + for_each_online_cpu(j) + any_count |= kstat_irqs_cpu(i, j); + action = desc->action; + if (!action && !any_count) + goto out; + + seq_printf(p, "%*d: ", prec, i); + for_each_online_cpu(j) + seq_printf(p, "%10u ", kstat_irqs_cpu(i, j)); + + if (desc->irq_data.chip) { + if (desc->irq_data.chip->irq_print_chip) + desc->irq_data.chip->irq_print_chip(&desc->irq_data, p); + else if (desc->irq_data.chip->name) + seq_printf(p, " %8s", desc->irq_data.chip->name); + else + seq_printf(p, " %8s", "-"); + } else { + seq_printf(p, " %8s", "None"); + } +#ifdef CONFIG_GENERIC_IRQ_SHOW_LEVEL + seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge"); +#endif + if (desc->name) + seq_printf(p, "-%-8s", desc->name); + + if (action) { + seq_printf(p, " %s", action->name); + while ((action = action->next) != NULL) + seq_printf(p, ", %s", action->name); + } + + seq_putc(p, '\n'); +out: + raw_spin_unlock_irqrestore(&desc->lock, flags); + return 0; +} +#endif diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c index 891115a929a..14dd5761e8c 100644 --- a/kernel/irq/resend.c +++ b/kernel/irq/resend.c @@ -23,7 +23,7 @@ #ifdef CONFIG_HARDIRQS_SW_RESEND /* Bitmap to handle software resend of interrupts: */ -static DECLARE_BITMAP(irqs_resend, NR_IRQS); +static DECLARE_BITMAP(irqs_resend, IRQ_BITMAP_BITS); /* * Run software resends of IRQ's @@ -55,20 +55,18 @@ static DECLARE_TASKLET(resend_tasklet, resend_irqs, 0); */ void check_irq_resend(struct irq_desc *desc, unsigned int irq) { - unsigned int status = desc->status; - - /* - * Make sure the interrupt is enabled, before resending it: - */ - desc->irq_data.chip->irq_enable(&desc->irq_data); - /* * We do not resend level type interrupts. Level type * interrupts are resent by hardware when they are still * active. */ - if ((status & (IRQ_LEVEL | IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) { - desc->status = (status & ~IRQ_PENDING) | IRQ_REPLAY; + if (irq_settings_is_level(desc)) + return; + if (desc->istate & IRQS_REPLAY) + return; + if (desc->istate & IRQS_PENDING) { + desc->istate &= ~IRQS_PENDING; + desc->istate |= IRQS_REPLAY; if (!desc->irq_data.chip->irq_retrigger || !desc->irq_data.chip->irq_retrigger(&desc->irq_data)) { diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h new file mode 100644 index 00000000000..f1667833d44 --- /dev/null +++ b/kernel/irq/settings.h @@ -0,0 +1,142 @@ +/* + * Internal header to deal with irq_desc->status which will be renamed + * to irq_desc->settings. + */ +enum { + _IRQ_DEFAULT_INIT_FLAGS = IRQ_DEFAULT_INIT_FLAGS, + _IRQ_PER_CPU = IRQ_PER_CPU, + _IRQ_LEVEL = IRQ_LEVEL, + _IRQ_NOPROBE = IRQ_NOPROBE, + _IRQ_NOREQUEST = IRQ_NOREQUEST, + _IRQ_NOTHREAD = IRQ_NOTHREAD, + _IRQ_NOAUTOEN = IRQ_NOAUTOEN, + _IRQ_MOVE_PCNTXT = IRQ_MOVE_PCNTXT, + _IRQ_NO_BALANCING = IRQ_NO_BALANCING, + _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, + _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, +}; + +#define IRQ_PER_CPU GOT_YOU_MORON +#define IRQ_NO_BALANCING GOT_YOU_MORON +#define IRQ_LEVEL GOT_YOU_MORON +#define IRQ_NOPROBE GOT_YOU_MORON +#define IRQ_NOREQUEST GOT_YOU_MORON +#define IRQ_NOTHREAD GOT_YOU_MORON +#define IRQ_NOAUTOEN GOT_YOU_MORON +#define IRQ_NESTED_THREAD GOT_YOU_MORON +#undef IRQF_MODIFY_MASK +#define IRQF_MODIFY_MASK GOT_YOU_MORON + +static inline void +irq_settings_clr_and_set(struct irq_desc *desc, u32 clr, u32 set) +{ + desc->status_use_accessors &= ~(clr & _IRQF_MODIFY_MASK); + desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK); +} + +static inline bool irq_settings_is_per_cpu(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_PER_CPU; +} + +static inline void irq_settings_set_per_cpu(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_PER_CPU; +} + +static inline void irq_settings_set_no_balancing(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NO_BALANCING; +} + +static inline bool irq_settings_has_no_balance_set(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NO_BALANCING; +} + +static inline u32 irq_settings_get_trigger_mask(struct irq_desc *desc) +{ + return desc->status_use_accessors & IRQ_TYPE_SENSE_MASK; +} + +static inline void +irq_settings_set_trigger_mask(struct irq_desc *desc, u32 mask) +{ + desc->status_use_accessors &= ~IRQ_TYPE_SENSE_MASK; + desc->status_use_accessors |= mask & IRQ_TYPE_SENSE_MASK; +} + +static inline bool irq_settings_is_level(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_LEVEL; +} + +static inline void irq_settings_clr_level(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_LEVEL; +} + +static inline void irq_settings_set_level(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_LEVEL; +} + +static inline bool irq_settings_can_request(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOREQUEST); +} + +static inline void irq_settings_clr_norequest(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOREQUEST; +} + +static inline void irq_settings_set_norequest(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOREQUEST; +} + +static inline bool irq_settings_can_thread(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOTHREAD); +} + +static inline void irq_settings_clr_nothread(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOTHREAD; +} + +static inline void irq_settings_set_nothread(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOTHREAD; +} + +static inline bool irq_settings_can_probe(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOPROBE); +} + +static inline void irq_settings_clr_noprobe(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_NOPROBE; +} + +static inline void irq_settings_set_noprobe(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NOPROBE; +} + +static inline bool irq_settings_can_move_pcntxt(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_MOVE_PCNTXT; +} + +static inline bool irq_settings_can_autoenable(struct irq_desc *desc) +{ + return !(desc->status_use_accessors & _IRQ_NOAUTOEN); +} + +static inline bool irq_settings_is_nested_thread(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NESTED_THREAD; +} diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index 3089d3b9d5f..dfbd550401b 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -21,70 +21,93 @@ static int irqfixup __read_mostly; #define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10) static void poll_spurious_irqs(unsigned long dummy); static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs, 0, 0); +static int irq_poll_cpu; +static atomic_t irq_poll_active; + +/* + * We wait here for a poller to finish. + * + * If the poll runs on this CPU, then we yell loudly and return + * false. That will leave the interrupt line disabled in the worst + * case, but it should never happen. + * + * We wait until the poller is done and then recheck disabled and + * action (about to be disabled). Only if it's still active, we return + * true and let the handler run. + */ +bool irq_wait_for_poll(struct irq_desc *desc) +{ + if (WARN_ONCE(irq_poll_cpu == smp_processor_id(), + "irq poll in progress on cpu %d for irq %d\n", + smp_processor_id(), desc->irq_data.irq)) + return false; + +#ifdef CONFIG_SMP + do { + raw_spin_unlock(&desc->lock); + while (irqd_irq_inprogress(&desc->irq_data)) + cpu_relax(); + raw_spin_lock(&desc->lock); + } while (irqd_irq_inprogress(&desc->irq_data)); + /* Might have been disabled in meantime */ + return !irqd_irq_disabled(&desc->irq_data) && desc->action; +#else + return false; +#endif +} + /* * Recovery handler for misrouted interrupts. */ -static int try_one_irq(int irq, struct irq_desc *desc) +static int try_one_irq(int irq, struct irq_desc *desc, bool force) { + irqreturn_t ret = IRQ_NONE; struct irqaction *action; - int ok = 0, work = 0; raw_spin_lock(&desc->lock); - /* Already running on another processor */ - if (desc->status & IRQ_INPROGRESS) { - /* - * Already running: If it is shared get the other - * CPU to go looking for our mystery interrupt too - */ - if (desc->action && (desc->action->flags & IRQF_SHARED)) - desc->status |= IRQ_PENDING; - raw_spin_unlock(&desc->lock); - return ok; - } - /* Honour the normal IRQ locking */ - desc->status |= IRQ_INPROGRESS; - action = desc->action; - raw_spin_unlock(&desc->lock); - while (action) { - /* Only shared IRQ handlers are safe to call */ - if (action->flags & IRQF_SHARED) { - if (action->handler(irq, action->dev_id) == - IRQ_HANDLED) - ok = 1; - } - action = action->next; - } - local_irq_disable(); - /* Now clean up the flags */ - raw_spin_lock(&desc->lock); - action = desc->action; + /* PER_CPU and nested thread interrupts are never polled */ + if (irq_settings_is_per_cpu(desc) || irq_settings_is_nested_thread(desc)) + goto out; /* - * While we were looking for a fixup someone queued a real - * IRQ clashing with our walk: + * Do not poll disabled interrupts unless the spurious + * disabled poller asks explicitely. */ - while ((desc->status & IRQ_PENDING) && action) { + if (irqd_irq_disabled(&desc->irq_data) && !force) + goto out; + + /* + * All handlers must agree on IRQF_SHARED, so we test just the + * first. Check for action->next as well. + */ + action = desc->action; + if (!action || !(action->flags & IRQF_SHARED) || + (action->flags & __IRQF_TIMER) || !action->next) + goto out; + + /* Already running on another processor */ + if (irqd_irq_inprogress(&desc->irq_data)) { /* - * Perform real IRQ processing for the IRQ we deferred + * Already running: If it is shared get the other + * CPU to go looking for our mystery interrupt too */ - work = 1; - raw_spin_unlock(&desc->lock); - handle_IRQ_event(irq, action); - raw_spin_lock(&desc->lock); - desc->status &= ~IRQ_PENDING; + desc->istate |= IRQS_PENDING; + goto out; } - desc->status &= ~IRQ_INPROGRESS; - /* - * If we did actual work for the real IRQ line we must let the - * IRQ controller clean up too - */ - if (work) - irq_end(irq, desc); - raw_spin_unlock(&desc->lock); - return ok; + /* Mark it poll in progress */ + desc->istate |= IRQS_POLL_INPROGRESS; + do { + if (handle_irq_event(desc) == IRQ_HANDLED) + ret = IRQ_HANDLED; + action = desc->action; + } while ((desc->istate & IRQS_PENDING) && action); + desc->istate &= ~IRQS_POLL_INPROGRESS; +out: + raw_spin_unlock(&desc->lock); + return ret == IRQ_HANDLED; } static int misrouted_irq(int irq) @@ -92,6 +115,11 @@ static int misrouted_irq(int irq) struct irq_desc *desc; int i, ok = 0; + if (atomic_inc_return(&irq_poll_active) == 1) + goto out; + + irq_poll_cpu = smp_processor_id(); + for_each_irq_desc(i, desc) { if (!i) continue; @@ -99,9 +127,11 @@ static int misrouted_irq(int irq) if (i == irq) /* Already tried */ continue; - if (try_one_irq(i, desc)) + if (try_one_irq(i, desc, false)) ok = 1; } +out: + atomic_dec(&irq_poll_active); /* So the caller can adjust the irq error counts */ return ok; } @@ -111,23 +141,28 @@ static void poll_spurious_irqs(unsigned long dummy) struct irq_desc *desc; int i; + if (atomic_inc_return(&irq_poll_active) != 1) + goto out; + irq_poll_cpu = smp_processor_id(); + for_each_irq_desc(i, desc) { - unsigned int status; + unsigned int state; if (!i) continue; /* Racy but it doesn't matter */ - status = desc->status; + state = desc->istate; barrier(); - if (!(status & IRQ_SPURIOUS_DISABLED)) + if (!(state & IRQS_SPURIOUS_DISABLED)) continue; local_irq_disable(); - try_one_irq(i, desc); + try_one_irq(i, desc, true); local_irq_enable(); } - +out: + atomic_dec(&irq_poll_active); mod_timer(&poll_spurious_irq_timer, jiffies + POLL_SPURIOUS_IRQ_INTERVAL); } @@ -139,15 +174,13 @@ static void poll_spurious_irqs(unsigned long dummy) * * (The other 100-of-100,000 interrupts may have been a correctly * functioning device sharing an IRQ with the failing one) - * - * Called under desc->lock */ - static void __report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) { struct irqaction *action; + unsigned long flags; if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) { printk(KERN_ERR "irq event %d: bogus return value %x\n", @@ -159,6 +192,13 @@ __report_bad_irq(unsigned int irq, struct irq_desc *desc, dump_stack(); printk(KERN_ERR "handlers:\n"); + /* + * We need to take desc->lock here. note_interrupt() is called + * w/o desc->lock held, but IRQ_PROGRESS set. We might race + * with something else removing an action. It's ok to take + * desc->lock here. See synchronize_irq(). + */ + raw_spin_lock_irqsave(&desc->lock, flags); action = desc->action; while (action) { printk(KERN_ERR "[<%p>]", action->handler); @@ -167,6 +207,7 @@ __report_bad_irq(unsigned int irq, struct irq_desc *desc, printk("\n"); action = action->next; } + raw_spin_unlock_irqrestore(&desc->lock, flags); } static void @@ -218,6 +259,9 @@ try_misrouted_irq(unsigned int irq, struct irq_desc *desc, void note_interrupt(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) { + if (desc->istate & IRQS_POLL_INPROGRESS) + return; + if (unlikely(action_ret != IRQ_HANDLED)) { /* * If we are seeing only the odd spurious IRQ caused by @@ -254,9 +298,9 @@ void note_interrupt(unsigned int irq, struct irq_desc *desc, * Now kill the IRQ */ printk(KERN_EMERG "Disabling IRQ #%d\n", irq); - desc->status |= IRQ_DISABLED | IRQ_SPURIOUS_DISABLED; + desc->istate |= IRQS_SPURIOUS_DISABLED; desc->depth++; - desc->irq_data.chip->irq_disable(&desc->irq_data); + irq_disable(desc); mod_timer(&poll_spurious_irq_timer, jiffies + POLL_SPURIOUS_IRQ_INTERVAL); diff --git a/kernel/irq_work.c b/kernel/irq_work.c index f16763ff848..c58fa7da8ae 100644 --- a/kernel/irq_work.c +++ b/kernel/irq_work.c @@ -77,21 +77,21 @@ void __weak arch_irq_work_raise(void) */ static void __irq_work_queue(struct irq_work *entry) { - struct irq_work **head, *next; + struct irq_work *next; - head = &get_cpu_var(irq_work_list); + preempt_disable(); do { - next = *head; + next = __this_cpu_read(irq_work_list); /* Can assign non-atomic because we keep the flags set. */ entry->next = next_flags(next, IRQ_WORK_FLAGS); - } while (cmpxchg(head, next, entry) != next); + } while (this_cpu_cmpxchg(irq_work_list, next, entry) != next); /* The list was empty, raise self-interrupt to start processing. */ if (!irq_work_next(entry)) arch_irq_work_raise(); - put_cpu_var(irq_work_list); + preempt_enable(); } /* @@ -120,16 +120,16 @@ EXPORT_SYMBOL_GPL(irq_work_queue); */ void irq_work_run(void) { - struct irq_work *list, **head; + struct irq_work *list; - head = &__get_cpu_var(irq_work_list); - if (*head == NULL) + if (this_cpu_read(irq_work_list) == NULL) return; BUG_ON(!in_irq()); BUG_ON(!irqs_disabled()); - list = xchg(head, NULL); + list = this_cpu_xchg(irq_work_list, NULL); + while (list != NULL) { struct irq_work *entry = list; @@ -145,7 +145,9 @@ void irq_work_run(void) * Clear the BUSY bit and return to the free state if * no-one else claimed it meanwhile. */ - cmpxchg(&entry->next, next_flags(NULL, IRQ_WORK_BUSY), NULL); + (void)cmpxchg(&entry->next, + next_flags(NULL, IRQ_WORK_BUSY), + NULL); } } EXPORT_SYMBOL_GPL(irq_work_run); diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 3b79bd93833..74d1c099fbd 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -2,43 +2,23 @@ * jump label support * * Copyright (C) 2009 Jason Baron <jbaron@redhat.com> + * Copyright (C) 2011 Peter Zijlstra <pzijlstr@redhat.com> * */ -#include <linux/jump_label.h> #include <linux/memory.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/list.h> -#include <linux/jhash.h> #include <linux/slab.h> #include <linux/sort.h> #include <linux/err.h> +#include <linux/jump_label.h> #ifdef HAVE_JUMP_LABEL -#define JUMP_LABEL_HASH_BITS 6 -#define JUMP_LABEL_TABLE_SIZE (1 << JUMP_LABEL_HASH_BITS) -static struct hlist_head jump_label_table[JUMP_LABEL_TABLE_SIZE]; - /* mutex to protect coming/going of the the jump_label table */ static DEFINE_MUTEX(jump_label_mutex); -struct jump_label_entry { - struct hlist_node hlist; - struct jump_entry *table; - int nr_entries; - /* hang modules off here */ - struct hlist_head modules; - unsigned long key; -}; - -struct jump_label_module_entry { - struct hlist_node hlist; - struct jump_entry *table; - int nr_entries; - struct module *mod; -}; - void jump_label_lock(void) { mutex_lock(&jump_label_mutex); @@ -49,6 +29,11 @@ void jump_label_unlock(void) mutex_unlock(&jump_label_mutex); } +bool jump_label_enabled(struct jump_label_key *key) +{ + return !!atomic_read(&key->enabled); +} + static int jump_label_cmp(const void *a, const void *b) { const struct jump_entry *jea = a; @@ -64,7 +49,7 @@ static int jump_label_cmp(const void *a, const void *b) } static void -sort_jump_label_entries(struct jump_entry *start, struct jump_entry *stop) +jump_label_sort_entries(struct jump_entry *start, struct jump_entry *stop) { unsigned long size; @@ -73,118 +58,25 @@ sort_jump_label_entries(struct jump_entry *start, struct jump_entry *stop) sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL); } -static struct jump_label_entry *get_jump_label_entry(jump_label_t key) -{ - struct hlist_head *head; - struct hlist_node *node; - struct jump_label_entry *e; - u32 hash = jhash((void *)&key, sizeof(jump_label_t), 0); - - head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)]; - hlist_for_each_entry(e, node, head, hlist) { - if (key == e->key) - return e; - } - return NULL; -} +static void jump_label_update(struct jump_label_key *key, int enable); -static struct jump_label_entry * -add_jump_label_entry(jump_label_t key, int nr_entries, struct jump_entry *table) +void jump_label_inc(struct jump_label_key *key) { - struct hlist_head *head; - struct jump_label_entry *e; - u32 hash; - - e = get_jump_label_entry(key); - if (e) - return ERR_PTR(-EEXIST); - - e = kmalloc(sizeof(struct jump_label_entry), GFP_KERNEL); - if (!e) - return ERR_PTR(-ENOMEM); - - hash = jhash((void *)&key, sizeof(jump_label_t), 0); - head = &jump_label_table[hash & (JUMP_LABEL_TABLE_SIZE - 1)]; - e->key = key; - e->table = table; - e->nr_entries = nr_entries; - INIT_HLIST_HEAD(&(e->modules)); - hlist_add_head(&e->hlist, head); - return e; -} + if (atomic_inc_not_zero(&key->enabled)) + return; -static int -build_jump_label_hashtable(struct jump_entry *start, struct jump_entry *stop) -{ - struct jump_entry *iter, *iter_begin; - struct jump_label_entry *entry; - int count; - - sort_jump_label_entries(start, stop); - iter = start; - while (iter < stop) { - entry = get_jump_label_entry(iter->key); - if (!entry) { - iter_begin = iter; - count = 0; - while ((iter < stop) && - (iter->key == iter_begin->key)) { - iter++; - count++; - } - entry = add_jump_label_entry(iter_begin->key, - count, iter_begin); - if (IS_ERR(entry)) - return PTR_ERR(entry); - } else { - WARN_ONCE(1, KERN_ERR "build_jump_hashtable: unexpected entry!\n"); - return -1; - } - } - return 0; + jump_label_lock(); + if (atomic_add_return(1, &key->enabled) == 1) + jump_label_update(key, JUMP_LABEL_ENABLE); + jump_label_unlock(); } -/*** - * jump_label_update - update jump label text - * @key - key value associated with a a jump label - * @type - enum set to JUMP_LABEL_ENABLE or JUMP_LABEL_DISABLE - * - * Will enable/disable the jump for jump label @key, depending on the - * value of @type. - * - */ - -void jump_label_update(unsigned long key, enum jump_label_type type) +void jump_label_dec(struct jump_label_key *key) { - struct jump_entry *iter; - struct jump_label_entry *entry; - struct hlist_node *module_node; - struct jump_label_module_entry *e_module; - int count; + if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) + return; - jump_label_lock(); - entry = get_jump_label_entry((jump_label_t)key); - if (entry) { - count = entry->nr_entries; - iter = entry->table; - while (count--) { - if (kernel_text_address(iter->code)) - arch_jump_label_transform(iter, type); - iter++; - } - /* eanble/disable jump labels in modules */ - hlist_for_each_entry(e_module, module_node, &(entry->modules), - hlist) { - count = e_module->nr_entries; - iter = e_module->table; - while (count--) { - if (iter->key && - kernel_text_address(iter->code)) - arch_jump_label_transform(iter, type); - iter++; - } - } - } + jump_label_update(key, JUMP_LABEL_DISABLE); jump_label_unlock(); } @@ -197,77 +89,33 @@ static int addr_conflict(struct jump_entry *entry, void *start, void *end) return 0; } -#ifdef CONFIG_MODULES - -static int module_conflict(void *start, void *end) +static int __jump_label_text_reserved(struct jump_entry *iter_start, + struct jump_entry *iter_stop, void *start, void *end) { - struct hlist_head *head; - struct hlist_node *node, *node_next, *module_node, *module_node_next; - struct jump_label_entry *e; - struct jump_label_module_entry *e_module; struct jump_entry *iter; - int i, count; - int conflict = 0; - - for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) { - head = &jump_label_table[i]; - hlist_for_each_entry_safe(e, node, node_next, head, hlist) { - hlist_for_each_entry_safe(e_module, module_node, - module_node_next, - &(e->modules), hlist) { - count = e_module->nr_entries; - iter = e_module->table; - while (count--) { - if (addr_conflict(iter, start, end)) { - conflict = 1; - goto out; - } - iter++; - } - } - } - } -out: - return conflict; -} - -#endif - -/*** - * jump_label_text_reserved - check if addr range is reserved - * @start: start text addr - * @end: end text addr - * - * checks if the text addr located between @start and @end - * overlaps with any of the jump label patch addresses. Code - * that wants to modify kernel text should first verify that - * it does not overlap with any of the jump label addresses. - * Caller must hold jump_label_mutex. - * - * returns 1 if there is an overlap, 0 otherwise - */ -int jump_label_text_reserved(void *start, void *end) -{ - struct jump_entry *iter; - struct jump_entry *iter_start = __start___jump_table; - struct jump_entry *iter_stop = __start___jump_table; - int conflict = 0; iter = iter_start; while (iter < iter_stop) { - if (addr_conflict(iter, start, end)) { - conflict = 1; - goto out; - } + if (addr_conflict(iter, start, end)) + return 1; iter++; } - /* now check modules */ -#ifdef CONFIG_MODULES - conflict = module_conflict(start, end); -#endif -out: - return conflict; + return 0; +} + +static void __jump_label_update(struct jump_label_key *key, + struct jump_entry *entry, int enable) +{ + for (; entry->key == (jump_label_t)(unsigned long)key; entry++) { + /* + * entry->code set to 0 invalidates module init text sections + * kernel_text_address() verifies we are not in core kernel + * init code, see jump_label_invalidate_module_init(). + */ + if (entry->code && kernel_text_address(entry->code)) + arch_jump_label_transform(entry, enable); + } } /* @@ -277,142 +125,173 @@ void __weak arch_jump_label_text_poke_early(jump_label_t addr) { } -static __init int init_jump_label(void) +static __init int jump_label_init(void) { - int ret; struct jump_entry *iter_start = __start___jump_table; struct jump_entry *iter_stop = __stop___jump_table; + struct jump_label_key *key = NULL; struct jump_entry *iter; jump_label_lock(); - ret = build_jump_label_hashtable(__start___jump_table, - __stop___jump_table); - iter = iter_start; - while (iter < iter_stop) { + jump_label_sort_entries(iter_start, iter_stop); + + for (iter = iter_start; iter < iter_stop; iter++) { arch_jump_label_text_poke_early(iter->code); - iter++; + if (iter->key == (jump_label_t)(unsigned long)key) + continue; + + key = (struct jump_label_key *)(unsigned long)iter->key; + atomic_set(&key->enabled, 0); + key->entries = iter; +#ifdef CONFIG_MODULES + key->next = NULL; +#endif } jump_label_unlock(); - return ret; + + return 0; } -early_initcall(init_jump_label); +early_initcall(jump_label_init); #ifdef CONFIG_MODULES -static struct jump_label_module_entry * -add_jump_label_module_entry(struct jump_label_entry *entry, - struct jump_entry *iter_begin, - int count, struct module *mod) +struct jump_label_mod { + struct jump_label_mod *next; + struct jump_entry *entries; + struct module *mod; +}; + +static int __jump_label_mod_text_reserved(void *start, void *end) +{ + struct module *mod; + + mod = __module_text_address((unsigned long)start); + if (!mod) + return 0; + + WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod); + + return __jump_label_text_reserved(mod->jump_entries, + mod->jump_entries + mod->num_jump_entries, + start, end); +} + +static void __jump_label_mod_update(struct jump_label_key *key, int enable) +{ + struct jump_label_mod *mod = key->next; + + while (mod) { + __jump_label_update(key, mod->entries, enable); + mod = mod->next; + } +} + +/*** + * apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop() + * @mod: module to patch + * + * Allow for run-time selection of the optimal nops. Before the module + * loads patch these with arch_get_jump_label_nop(), which is specified by + * the arch specific jump label code. + */ +void jump_label_apply_nops(struct module *mod) { - struct jump_label_module_entry *e; - - e = kmalloc(sizeof(struct jump_label_module_entry), GFP_KERNEL); - if (!e) - return ERR_PTR(-ENOMEM); - e->mod = mod; - e->nr_entries = count; - e->table = iter_begin; - hlist_add_head(&e->hlist, &entry->modules); - return e; + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; + struct jump_entry *iter; + + /* if the module doesn't have jump label entries, just return */ + if (iter_start == iter_stop) + return; + + for (iter = iter_start; iter < iter_stop; iter++) + arch_jump_label_text_poke_early(iter->code); } -static int add_jump_label_module(struct module *mod) +static int jump_label_add_module(struct module *mod) { - struct jump_entry *iter, *iter_begin; - struct jump_label_entry *entry; - struct jump_label_module_entry *module_entry; - int count; + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; + struct jump_entry *iter; + struct jump_label_key *key = NULL; + struct jump_label_mod *jlm; /* if the module doesn't have jump label entries, just return */ - if (!mod->num_jump_entries) + if (iter_start == iter_stop) return 0; - sort_jump_label_entries(mod->jump_entries, - mod->jump_entries + mod->num_jump_entries); - iter = mod->jump_entries; - while (iter < mod->jump_entries + mod->num_jump_entries) { - entry = get_jump_label_entry(iter->key); - iter_begin = iter; - count = 0; - while ((iter < mod->jump_entries + mod->num_jump_entries) && - (iter->key == iter_begin->key)) { - iter++; - count++; - } - if (!entry) { - entry = add_jump_label_entry(iter_begin->key, 0, NULL); - if (IS_ERR(entry)) - return PTR_ERR(entry); + jump_label_sort_entries(iter_start, iter_stop); + + for (iter = iter_start; iter < iter_stop; iter++) { + if (iter->key == (jump_label_t)(unsigned long)key) + continue; + + key = (struct jump_label_key *)(unsigned long)iter->key; + + if (__module_address(iter->key) == mod) { + atomic_set(&key->enabled, 0); + key->entries = iter; + key->next = NULL; + continue; } - module_entry = add_jump_label_module_entry(entry, iter_begin, - count, mod); - if (IS_ERR(module_entry)) - return PTR_ERR(module_entry); + + jlm = kzalloc(sizeof(struct jump_label_mod), GFP_KERNEL); + if (!jlm) + return -ENOMEM; + + jlm->mod = mod; + jlm->entries = iter; + jlm->next = key->next; + key->next = jlm; + + if (jump_label_enabled(key)) + __jump_label_update(key, iter, JUMP_LABEL_ENABLE); } + return 0; } -static void remove_jump_label_module(struct module *mod) +static void jump_label_del_module(struct module *mod) { - struct hlist_head *head; - struct hlist_node *node, *node_next, *module_node, *module_node_next; - struct jump_label_entry *e; - struct jump_label_module_entry *e_module; - int i; + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; + struct jump_entry *iter; + struct jump_label_key *key = NULL; + struct jump_label_mod *jlm, **prev; - /* if the module doesn't have jump label entries, just return */ - if (!mod->num_jump_entries) - return; + for (iter = iter_start; iter < iter_stop; iter++) { + if (iter->key == (jump_label_t)(unsigned long)key) + continue; + + key = (struct jump_label_key *)(unsigned long)iter->key; + + if (__module_address(iter->key) == mod) + continue; + + prev = &key->next; + jlm = key->next; - for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) { - head = &jump_label_table[i]; - hlist_for_each_entry_safe(e, node, node_next, head, hlist) { - hlist_for_each_entry_safe(e_module, module_node, - module_node_next, - &(e->modules), hlist) { - if (e_module->mod == mod) { - hlist_del(&e_module->hlist); - kfree(e_module); - } - } - if (hlist_empty(&e->modules) && (e->nr_entries == 0)) { - hlist_del(&e->hlist); - kfree(e); - } + while (jlm && jlm->mod != mod) { + prev = &jlm->next; + jlm = jlm->next; + } + + if (jlm) { + *prev = jlm->next; + kfree(jlm); } } } -static void remove_jump_label_module_init(struct module *mod) +static void jump_label_invalidate_module_init(struct module *mod) { - struct hlist_head *head; - struct hlist_node *node, *node_next, *module_node, *module_node_next; - struct jump_label_entry *e; - struct jump_label_module_entry *e_module; + struct jump_entry *iter_start = mod->jump_entries; + struct jump_entry *iter_stop = iter_start + mod->num_jump_entries; struct jump_entry *iter; - int i, count; - - /* if the module doesn't have jump label entries, just return */ - if (!mod->num_jump_entries) - return; - for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) { - head = &jump_label_table[i]; - hlist_for_each_entry_safe(e, node, node_next, head, hlist) { - hlist_for_each_entry_safe(e_module, module_node, - module_node_next, - &(e->modules), hlist) { - if (e_module->mod != mod) - continue; - count = e_module->nr_entries; - iter = e_module->table; - while (count--) { - if (within_module_init(iter->code, mod)) - iter->key = 0; - iter++; - } - } - } + for (iter = iter_start; iter < iter_stop; iter++) { + if (within_module_init(iter->code, mod)) + iter->code = 0; } } @@ -426,59 +305,77 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val, switch (val) { case MODULE_STATE_COMING: jump_label_lock(); - ret = add_jump_label_module(mod); + ret = jump_label_add_module(mod); if (ret) - remove_jump_label_module(mod); + jump_label_del_module(mod); jump_label_unlock(); break; case MODULE_STATE_GOING: jump_label_lock(); - remove_jump_label_module(mod); + jump_label_del_module(mod); jump_label_unlock(); break; case MODULE_STATE_LIVE: jump_label_lock(); - remove_jump_label_module_init(mod); + jump_label_invalidate_module_init(mod); jump_label_unlock(); break; } - return ret; -} -/*** - * apply_jump_label_nops - patch module jump labels with arch_get_jump_label_nop() - * @mod: module to patch - * - * Allow for run-time selection of the optimal nops. Before the module - * loads patch these with arch_get_jump_label_nop(), which is specified by - * the arch specific jump label code. - */ -void jump_label_apply_nops(struct module *mod) -{ - struct jump_entry *iter; - - /* if the module doesn't have jump label entries, just return */ - if (!mod->num_jump_entries) - return; - - iter = mod->jump_entries; - while (iter < mod->jump_entries + mod->num_jump_entries) { - arch_jump_label_text_poke_early(iter->code); - iter++; - } + return notifier_from_errno(ret); } struct notifier_block jump_label_module_nb = { .notifier_call = jump_label_module_notify, - .priority = 0, + .priority = 1, /* higher than tracepoints */ }; -static __init int init_jump_label_module(void) +static __init int jump_label_init_module(void) { return register_module_notifier(&jump_label_module_nb); } -early_initcall(init_jump_label_module); +early_initcall(jump_label_init_module); #endif /* CONFIG_MODULES */ +/*** + * jump_label_text_reserved - check if addr range is reserved + * @start: start text addr + * @end: end text addr + * + * checks if the text addr located between @start and @end + * overlaps with any of the jump label patch addresses. Code + * that wants to modify kernel text should first verify that + * it does not overlap with any of the jump label addresses. + * Caller must hold jump_label_mutex. + * + * returns 1 if there is an overlap, 0 otherwise + */ +int jump_label_text_reserved(void *start, void *end) +{ + int ret = __jump_label_text_reserved(__start___jump_table, + __stop___jump_table, start, end); + + if (ret) + return ret; + +#ifdef CONFIG_MODULES + ret = __jump_label_mod_text_reserved(start, end); +#endif + return ret; +} + +static void jump_label_update(struct jump_label_key *key, int enable) +{ + struct jump_entry *entry = key->entries; + + /* if there are no users, entry can be NULL */ + if (entry) + __jump_label_update(key, entry, enable); + +#ifdef CONFIG_MODULES + __jump_label_mod_update(key, enable); +#endif +} + #endif diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 6f6d091b575..079f1d39a8b 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -64,14 +64,14 @@ static inline int is_kernel_text(unsigned long addr) if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) || arch_is_kernel_text(addr)) return 1; - return in_gate_area_no_task(addr); + return in_gate_area_no_mm(addr); } static inline int is_kernel(unsigned long addr) { if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end) return 1; - return in_gate_area_no_task(addr); + return in_gate_area_no_mm(addr); } static int is_ksym_addr(unsigned long addr) @@ -342,13 +342,15 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size, } /* Look up a kernel symbol and return it in a text buffer. */ -int sprint_symbol(char *buffer, unsigned long address) +static int __sprint_symbol(char *buffer, unsigned long address, + int symbol_offset) { char *modname; const char *name; unsigned long offset, size; int len; + address += symbol_offset; name = kallsyms_lookup(address, &size, &offset, &modname, buffer); if (!name) return sprintf(buffer, "0x%lx", address); @@ -357,17 +359,53 @@ int sprint_symbol(char *buffer, unsigned long address) strcpy(buffer, name); len = strlen(buffer); buffer += len; + offset -= symbol_offset; if (modname) - len += sprintf(buffer, "+%#lx/%#lx [%s]", - offset, size, modname); + len += sprintf(buffer, "+%#lx/%#lx [%s]", offset, size, modname); else len += sprintf(buffer, "+%#lx/%#lx", offset, size); return len; } + +/** + * sprint_symbol - Look up a kernel symbol and return it in a text buffer + * @buffer: buffer to be stored + * @address: address to lookup + * + * This function looks up a kernel symbol with @address and stores its name, + * offset, size and module name to @buffer if possible. If no symbol was found, + * just saves its @address as is. + * + * This function returns the number of bytes stored in @buffer. + */ +int sprint_symbol(char *buffer, unsigned long address) +{ + return __sprint_symbol(buffer, address, 0); +} + EXPORT_SYMBOL_GPL(sprint_symbol); +/** + * sprint_backtrace - Look up a backtrace symbol and return it in a text buffer + * @buffer: buffer to be stored + * @address: address to lookup + * + * This function is for stack backtrace and does the same thing as + * sprint_symbol() but with modified/decreased @address. If there is a + * tail-call to the function marked "noreturn", gcc optimized out code after + * the call so that the stack-saved return address could point outside of the + * caller. This function ensures that kallsyms will find the original caller + * by decreasing @address. + * + * This function returns the number of bytes stored in @buffer. + */ +int sprint_backtrace(char *buffer, unsigned long address) +{ + return __sprint_symbol(buffer, address, -1); +} + /* Look up a kernel symbol and print it to the kernel messages. */ void __print_symbol(const char *fmt, unsigned long address) { @@ -477,13 +515,11 @@ static int s_show(struct seq_file *m, void *p) */ type = iter->exported ? toupper(iter->type) : tolower(iter->type); - seq_printf(m, "%0*lx %c %s\t[%s]\n", - (int)(2 * sizeof(void *)), - iter->value, type, iter->name, iter->module_name); + seq_printf(m, "%pK %c %s\t[%s]\n", (void *)iter->value, + type, iter->name, iter->module_name); } else - seq_printf(m, "%0*lx %c %s\n", - (int)(2 * sizeof(void *)), - iter->value, iter->type, iter->name); + seq_printf(m, "%pK %c %s\n", (void *)iter->value, + iter->type, iter->name); return 0; } diff --git a/kernel/kexec.c b/kernel/kexec.c index b55045bc756..8d814cbc810 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -33,6 +33,7 @@ #include <linux/vmalloc.h> #include <linux/swap.h> #include <linux/kmsg_dump.h> +#include <linux/syscore_ops.h> #include <asm/page.h> #include <asm/uaccess.h> @@ -144,7 +145,7 @@ static int do_kimage_alloc(struct kimage **rimage, unsigned long entry, /* Initialize the list of destination pages */ INIT_LIST_HEAD(&image->dest_pages); - /* Initialize the list of unuseable pages */ + /* Initialize the list of unusable pages */ INIT_LIST_HEAD(&image->unuseable_pages); /* Read in the segments */ @@ -163,7 +164,7 @@ static int do_kimage_alloc(struct kimage **rimage, unsigned long entry, * just verifies it is an address we can use. * * Since the kernel does everything in page size chunks ensure - * the destination addreses are page aligned. Too many + * the destination addresses are page aligned. Too many * special cases crop of when we don't do this. The most * insidious is getting overlapping destination addresses * simply because addresses are changed to page size @@ -454,7 +455,7 @@ static struct page *kimage_alloc_normal_control_pages(struct kimage *image, /* Deal with the destination pages I have inadvertently allocated. * * Ideally I would convert multi-page allocations into single - * page allocations, and add everyting to image->dest_pages. + * page allocations, and add everything to image->dest_pages. * * For now it is simpler to just free the pages. */ @@ -602,7 +603,7 @@ static void kimage_free_extra_pages(struct kimage *image) /* Walk through and free any extra destination pages I may have */ kimage_free_page_list(&image->dest_pages); - /* Walk through and free any unuseable pages I have cached */ + /* Walk through and free any unusable pages I have cached */ kimage_free_page_list(&image->unuseable_pages); } @@ -1099,7 +1100,8 @@ size_t crash_get_memory_size(void) return size; } -static void free_reserved_phys_range(unsigned long begin, unsigned long end) +void __weak crash_free_reserved_phys_range(unsigned long begin, + unsigned long end) { unsigned long addr; @@ -1135,7 +1137,7 @@ int crash_shrink_memory(unsigned long new_size) start = roundup(start, PAGE_SIZE); end = roundup(start + new_size, PAGE_SIZE); - free_reserved_phys_range(end, crashk_res.end); + crash_free_reserved_phys_range(end, crashk_res.end); if ((start == end) && (crashk_res.parent != NULL)) release_resource(&crashk_res); @@ -1529,8 +1531,7 @@ int kernel_kexec(void) if (error) goto Enable_cpus; local_irq_disable(); - /* Suspend system devices */ - error = sysdev_suspend(PMSG_FREEZE); + error = syscore_suspend(); if (error) goto Enable_irqs; } else @@ -1545,7 +1546,7 @@ int kernel_kexec(void) #ifdef CONFIG_KEXEC_JUMP if (kexec_image->preserve_context) { - sysdev_resume(); + syscore_resume(); Enable_irqs: local_irq_enable(); Enable_cpus: diff --git a/kernel/kmod.c b/kernel/kmod.c index 9cd0591c96a..5ae0ff38425 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -245,7 +245,6 @@ static void __call_usermodehelper(struct work_struct *work) } } -#ifdef CONFIG_PM_SLEEP /* * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY * (used for preventing user land processes from being created after the user @@ -301,6 +300,15 @@ void usermodehelper_enable(void) usermodehelper_disabled = 0; } +/** + * usermodehelper_is_disabled - check if new helpers are allowed to be started + */ +bool usermodehelper_is_disabled(void) +{ + return usermodehelper_disabled; +} +EXPORT_SYMBOL_GPL(usermodehelper_is_disabled); + static void helper_lock(void) { atomic_inc(&running_helpers); @@ -312,12 +320,6 @@ static void helper_unlock(void) if (atomic_dec_and_test(&running_helpers)) wake_up(&running_helpers_waitq); } -#else /* CONFIG_PM_SLEEP */ -#define usermodehelper_disabled 0 - -static inline void helper_lock(void) {} -static inline void helper_unlock(void) {} -#endif /* CONFIG_PM_SLEEP */ /** * call_usermodehelper_setup - prepare to call a usermode helper diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9737a76e106..77981813a1e 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -317,12 +317,12 @@ void __kprobes free_optinsn_slot(kprobe_opcode_t * slot, int dirty) /* We have preemption disabled.. so it is safe to use __ versions */ static inline void set_kprobe_instance(struct kprobe *kp) { - __get_cpu_var(kprobe_instance) = kp; + __this_cpu_write(kprobe_instance, kp); } static inline void reset_kprobe_instance(void) { - __get_cpu_var(kprobe_instance) = NULL; + __this_cpu_write(kprobe_instance, NULL); } /* @@ -354,13 +354,20 @@ static inline int kprobe_aggrprobe(struct kprobe *p) return p->pre_handler == aggr_pre_handler; } +/* Return true(!0) if the kprobe is unused */ +static inline int kprobe_unused(struct kprobe *p) +{ + return kprobe_aggrprobe(p) && kprobe_disabled(p) && + list_empty(&p->list); +} + /* * Keep all fields in the kprobe consistent */ -static inline void copy_kprobe(struct kprobe *old_p, struct kprobe *p) +static inline void copy_kprobe(struct kprobe *ap, struct kprobe *p) { - memcpy(&p->opcode, &old_p->opcode, sizeof(kprobe_opcode_t)); - memcpy(&p->ainsn, &old_p->ainsn, sizeof(struct arch_specific_insn)); + memcpy(&p->opcode, &ap->opcode, sizeof(kprobe_opcode_t)); + memcpy(&p->ainsn, &ap->ainsn, sizeof(struct arch_specific_insn)); } #ifdef CONFIG_OPTPROBES @@ -384,6 +391,17 @@ void __kprobes opt_pre_handler(struct kprobe *p, struct pt_regs *regs) } } +/* Free optimized instructions and optimized_kprobe */ +static __kprobes void free_aggr_kprobe(struct kprobe *p) +{ + struct optimized_kprobe *op; + + op = container_of(p, struct optimized_kprobe, kp); + arch_remove_optimized_kprobe(op); + arch_remove_kprobe(p); + kfree(op); +} + /* Return true(!0) if the kprobe is ready for optimization. */ static inline int kprobe_optready(struct kprobe *p) { @@ -397,6 +415,33 @@ static inline int kprobe_optready(struct kprobe *p) return 0; } +/* Return true(!0) if the kprobe is disarmed. Note: p must be on hash list */ +static inline int kprobe_disarmed(struct kprobe *p) +{ + struct optimized_kprobe *op; + + /* If kprobe is not aggr/opt probe, just return kprobe is disabled */ + if (!kprobe_aggrprobe(p)) + return kprobe_disabled(p); + + op = container_of(p, struct optimized_kprobe, kp); + + return kprobe_disabled(p) && list_empty(&op->list); +} + +/* Return true(!0) if the probe is queued on (un)optimizing lists */ +static int __kprobes kprobe_queued(struct kprobe *p) +{ + struct optimized_kprobe *op; + + if (kprobe_aggrprobe(p)) { + op = container_of(p, struct optimized_kprobe, kp); + if (!list_empty(&op->list)) + return 1; + } + return 0; +} + /* * Return an optimized kprobe whose optimizing code replaces * instructions including addr (exclude breakpoint). @@ -422,30 +467,23 @@ static struct kprobe *__kprobes get_optimized_kprobe(unsigned long addr) /* Optimization staging list, protected by kprobe_mutex */ static LIST_HEAD(optimizing_list); +static LIST_HEAD(unoptimizing_list); static void kprobe_optimizer(struct work_struct *work); static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer); +static DECLARE_COMPLETION(optimizer_comp); #define OPTIMIZE_DELAY 5 -/* Kprobe jump optimizer */ -static __kprobes void kprobe_optimizer(struct work_struct *work) +/* + * Optimize (replace a breakpoint with a jump) kprobes listed on + * optimizing_list. + */ +static __kprobes void do_optimize_kprobes(void) { - struct optimized_kprobe *op, *tmp; - - /* Lock modules while optimizing kprobes */ - mutex_lock(&module_mutex); - mutex_lock(&kprobe_mutex); - if (kprobes_all_disarmed || !kprobes_allow_optimization) - goto end; - - /* - * Wait for quiesence period to ensure all running interrupts - * are done. Because optprobe may modify multiple instructions - * there is a chance that Nth instruction is interrupted. In that - * case, running interrupt can return to 2nd-Nth byte of jump - * instruction. This wait is for avoiding it. - */ - synchronize_sched(); + /* Optimization never be done when disarmed */ + if (kprobes_all_disarmed || !kprobes_allow_optimization || + list_empty(&optimizing_list)) + return; /* * The optimization/unoptimization refers online_cpus via @@ -459,17 +497,111 @@ static __kprobes void kprobe_optimizer(struct work_struct *work) */ get_online_cpus(); mutex_lock(&text_mutex); - list_for_each_entry_safe(op, tmp, &optimizing_list, list) { - WARN_ON(kprobe_disabled(&op->kp)); - if (arch_optimize_kprobe(op) < 0) - op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; - list_del_init(&op->list); + arch_optimize_kprobes(&optimizing_list); + mutex_unlock(&text_mutex); + put_online_cpus(); +} + +/* + * Unoptimize (replace a jump with a breakpoint and remove the breakpoint + * if need) kprobes listed on unoptimizing_list. + */ +static __kprobes void do_unoptimize_kprobes(struct list_head *free_list) +{ + struct optimized_kprobe *op, *tmp; + + /* Unoptimization must be done anytime */ + if (list_empty(&unoptimizing_list)) + return; + + /* Ditto to do_optimize_kprobes */ + get_online_cpus(); + mutex_lock(&text_mutex); + arch_unoptimize_kprobes(&unoptimizing_list, free_list); + /* Loop free_list for disarming */ + list_for_each_entry_safe(op, tmp, free_list, list) { + /* Disarm probes if marked disabled */ + if (kprobe_disabled(&op->kp)) + arch_disarm_kprobe(&op->kp); + if (kprobe_unused(&op->kp)) { + /* + * Remove unused probes from hash list. After waiting + * for synchronization, these probes are reclaimed. + * (reclaiming is done by do_free_cleaned_kprobes.) + */ + hlist_del_rcu(&op->kp.hlist); + } else + list_del_init(&op->list); } mutex_unlock(&text_mutex); put_online_cpus(); -end: +} + +/* Reclaim all kprobes on the free_list */ +static __kprobes void do_free_cleaned_kprobes(struct list_head *free_list) +{ + struct optimized_kprobe *op, *tmp; + + list_for_each_entry_safe(op, tmp, free_list, list) { + BUG_ON(!kprobe_unused(&op->kp)); + list_del_init(&op->list); + free_aggr_kprobe(&op->kp); + } +} + +/* Start optimizer after OPTIMIZE_DELAY passed */ +static __kprobes void kick_kprobe_optimizer(void) +{ + if (!delayed_work_pending(&optimizing_work)) + schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY); +} + +/* Kprobe jump optimizer */ +static __kprobes void kprobe_optimizer(struct work_struct *work) +{ + LIST_HEAD(free_list); + + /* Lock modules while optimizing kprobes */ + mutex_lock(&module_mutex); + mutex_lock(&kprobe_mutex); + + /* + * Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed) + * kprobes before waiting for quiesence period. + */ + do_unoptimize_kprobes(&free_list); + + /* + * Step 2: Wait for quiesence period to ensure all running interrupts + * are done. Because optprobe may modify multiple instructions + * there is a chance that Nth instruction is interrupted. In that + * case, running interrupt can return to 2nd-Nth byte of jump + * instruction. This wait is for avoiding it. + */ + synchronize_sched(); + + /* Step 3: Optimize kprobes after quiesence period */ + do_optimize_kprobes(); + + /* Step 4: Free cleaned kprobes after quiesence period */ + do_free_cleaned_kprobes(&free_list); + mutex_unlock(&kprobe_mutex); mutex_unlock(&module_mutex); + + /* Step 5: Kick optimizer again if needed */ + if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) + kick_kprobe_optimizer(); + else + /* Wake up all waiters */ + complete_all(&optimizer_comp); +} + +/* Wait for completing optimization and unoptimization */ +static __kprobes void wait_for_kprobe_optimizer(void) +{ + if (delayed_work_pending(&optimizing_work)) + wait_for_completion(&optimizer_comp); } /* Optimize kprobe if p is ready to be optimized */ @@ -495,42 +627,99 @@ static __kprobes void optimize_kprobe(struct kprobe *p) /* Check if it is already optimized. */ if (op->kp.flags & KPROBE_FLAG_OPTIMIZED) return; - op->kp.flags |= KPROBE_FLAG_OPTIMIZED; - list_add(&op->list, &optimizing_list); - if (!delayed_work_pending(&optimizing_work)) - schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY); + + if (!list_empty(&op->list)) + /* This is under unoptimizing. Just dequeue the probe */ + list_del_init(&op->list); + else { + list_add(&op->list, &optimizing_list); + kick_kprobe_optimizer(); + } +} + +/* Short cut to direct unoptimizing */ +static __kprobes void force_unoptimize_kprobe(struct optimized_kprobe *op) +{ + get_online_cpus(); + arch_unoptimize_kprobe(op); + put_online_cpus(); + if (kprobe_disabled(&op->kp)) + arch_disarm_kprobe(&op->kp); } /* Unoptimize a kprobe if p is optimized */ -static __kprobes void unoptimize_kprobe(struct kprobe *p) +static __kprobes void unoptimize_kprobe(struct kprobe *p, bool force) { struct optimized_kprobe *op; - if ((p->flags & KPROBE_FLAG_OPTIMIZED) && kprobe_aggrprobe(p)) { - op = container_of(p, struct optimized_kprobe, kp); - if (!list_empty(&op->list)) - /* Dequeue from the optimization queue */ + if (!kprobe_aggrprobe(p) || kprobe_disarmed(p)) + return; /* This is not an optprobe nor optimized */ + + op = container_of(p, struct optimized_kprobe, kp); + if (!kprobe_optimized(p)) { + /* Unoptimized or unoptimizing case */ + if (force && !list_empty(&op->list)) { + /* + * Only if this is unoptimizing kprobe and forced, + * forcibly unoptimize it. (No need to unoptimize + * unoptimized kprobe again :) + */ list_del_init(&op->list); - else - /* Replace jump with break */ - arch_unoptimize_kprobe(op); - op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; + force_unoptimize_kprobe(op); + } + return; + } + + op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; + if (!list_empty(&op->list)) { + /* Dequeue from the optimization queue */ + list_del_init(&op->list); + return; + } + /* Optimized kprobe case */ + if (force) + /* Forcibly update the code: this is a special case */ + force_unoptimize_kprobe(op); + else { + list_add(&op->list, &unoptimizing_list); + kick_kprobe_optimizer(); } } +/* Cancel unoptimizing for reusing */ +static void reuse_unused_kprobe(struct kprobe *ap) +{ + struct optimized_kprobe *op; + + BUG_ON(!kprobe_unused(ap)); + /* + * Unused kprobe MUST be on the way of delayed unoptimizing (means + * there is still a relative jump) and disabled. + */ + op = container_of(ap, struct optimized_kprobe, kp); + if (unlikely(list_empty(&op->list))) + printk(KERN_WARNING "Warning: found a stray unused " + "aggrprobe@%p\n", ap->addr); + /* Enable the probe again */ + ap->flags &= ~KPROBE_FLAG_DISABLED; + /* Optimize it again (remove from op->list) */ + BUG_ON(!kprobe_optready(ap)); + optimize_kprobe(ap); +} + /* Remove optimized instructions */ static void __kprobes kill_optimized_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); - if (!list_empty(&op->list)) { - /* Dequeue from the optimization queue */ + if (!list_empty(&op->list)) + /* Dequeue from the (un)optimization queue */ list_del_init(&op->list); - op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; - } - /* Don't unoptimize, because the target code will be freed. */ + + op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; + /* Don't touch the code, because it is already freed. */ arch_remove_optimized_kprobe(op); } @@ -543,16 +732,6 @@ static __kprobes void prepare_optimized_kprobe(struct kprobe *p) arch_prepare_optimized_kprobe(op); } -/* Free optimized instructions and optimized_kprobe */ -static __kprobes void free_aggr_kprobe(struct kprobe *p) -{ - struct optimized_kprobe *op; - - op = container_of(p, struct optimized_kprobe, kp); - arch_remove_optimized_kprobe(op); - kfree(op); -} - /* Allocate new optimized_kprobe and try to prepare optimized instructions */ static __kprobes struct kprobe *alloc_aggr_kprobe(struct kprobe *p) { @@ -587,7 +766,8 @@ static __kprobes void try_to_optimize_kprobe(struct kprobe *p) op = container_of(ap, struct optimized_kprobe, kp); if (!arch_prepared_optinsn(&op->optinsn)) { /* If failed to setup optimizing, fallback to kprobe */ - free_aggr_kprobe(ap); + arch_remove_optimized_kprobe(op); + kfree(op); return; } @@ -631,21 +811,16 @@ static void __kprobes unoptimize_all_kprobes(void) return; kprobes_allow_optimization = false; - printk(KERN_INFO "Kprobes globally unoptimized\n"); - get_online_cpus(); /* For avoiding text_mutex deadlock */ - mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) { if (!kprobe_disabled(p)) - unoptimize_kprobe(p); + unoptimize_kprobe(p, false); } } - - mutex_unlock(&text_mutex); - put_online_cpus(); - /* Allow all currently running kprobes to complete */ - synchronize_sched(); + /* Wait for unoptimizing completion */ + wait_for_kprobe_optimizer(); + printk(KERN_INFO "Kprobes globally unoptimized\n"); } int sysctl_kprobes_optimization; @@ -669,44 +844,60 @@ int proc_kprobes_optimization_handler(struct ctl_table *table, int write, } #endif /* CONFIG_SYSCTL */ +/* Put a breakpoint for a probe. Must be called with text_mutex locked */ static void __kprobes __arm_kprobe(struct kprobe *p) { - struct kprobe *old_p; + struct kprobe *_p; /* Check collision with other optimized kprobes */ - old_p = get_optimized_kprobe((unsigned long)p->addr); - if (unlikely(old_p)) - unoptimize_kprobe(old_p); /* Fallback to unoptimized kprobe */ + _p = get_optimized_kprobe((unsigned long)p->addr); + if (unlikely(_p)) + /* Fallback to unoptimized kprobe */ + unoptimize_kprobe(_p, true); arch_arm_kprobe(p); optimize_kprobe(p); /* Try to optimize (add kprobe to a list) */ } -static void __kprobes __disarm_kprobe(struct kprobe *p) +/* Remove the breakpoint of a probe. Must be called with text_mutex locked */ +static void __kprobes __disarm_kprobe(struct kprobe *p, bool reopt) { - struct kprobe *old_p; + struct kprobe *_p; - unoptimize_kprobe(p); /* Try to unoptimize */ - arch_disarm_kprobe(p); + unoptimize_kprobe(p, false); /* Try to unoptimize */ - /* If another kprobe was blocked, optimize it. */ - old_p = get_optimized_kprobe((unsigned long)p->addr); - if (unlikely(old_p)) - optimize_kprobe(old_p); + if (!kprobe_queued(p)) { + arch_disarm_kprobe(p); + /* If another kprobe was blocked, optimize it. */ + _p = get_optimized_kprobe((unsigned long)p->addr); + if (unlikely(_p) && reopt) + optimize_kprobe(_p); + } + /* TODO: reoptimize others after unoptimized this probe */ } #else /* !CONFIG_OPTPROBES */ #define optimize_kprobe(p) do {} while (0) -#define unoptimize_kprobe(p) do {} while (0) +#define unoptimize_kprobe(p, f) do {} while (0) #define kill_optimized_kprobe(p) do {} while (0) #define prepare_optimized_kprobe(p) do {} while (0) #define try_to_optimize_kprobe(p) do {} while (0) #define __arm_kprobe(p) arch_arm_kprobe(p) -#define __disarm_kprobe(p) arch_disarm_kprobe(p) +#define __disarm_kprobe(p, o) arch_disarm_kprobe(p) +#define kprobe_disarmed(p) kprobe_disabled(p) +#define wait_for_kprobe_optimizer() do {} while (0) + +/* There should be no unused kprobes can be reused without optimization */ +static void reuse_unused_kprobe(struct kprobe *ap) +{ + printk(KERN_ERR "Error: There should be no unused kprobe here.\n"); + BUG_ON(kprobe_unused(ap)); +} static __kprobes void free_aggr_kprobe(struct kprobe *p) { + arch_remove_kprobe(p); kfree(p); } @@ -732,11 +923,10 @@ static void __kprobes arm_kprobe(struct kprobe *kp) /* Disarm a kprobe with text_mutex */ static void __kprobes disarm_kprobe(struct kprobe *kp) { - get_online_cpus(); /* For avoiding text_mutex deadlock */ + /* Ditto */ mutex_lock(&text_mutex); - __disarm_kprobe(kp); + __disarm_kprobe(kp, true); mutex_unlock(&text_mutex); - put_online_cpus(); } /* @@ -775,7 +965,7 @@ static void __kprobes aggr_post_handler(struct kprobe *p, struct pt_regs *regs, static int __kprobes aggr_fault_handler(struct kprobe *p, struct pt_regs *regs, int trapnr) { - struct kprobe *cur = __get_cpu_var(kprobe_instance); + struct kprobe *cur = __this_cpu_read(kprobe_instance); /* * if we faulted "during" the execution of a user specified @@ -790,7 +980,7 @@ static int __kprobes aggr_fault_handler(struct kprobe *p, struct pt_regs *regs, static int __kprobes aggr_break_handler(struct kprobe *p, struct pt_regs *regs) { - struct kprobe *cur = __get_cpu_var(kprobe_instance); + struct kprobe *cur = __this_cpu_read(kprobe_instance); int ret = 0; if (cur && cur->break_handler) { @@ -942,7 +1132,7 @@ static int __kprobes add_new_kprobe(struct kprobe *ap, struct kprobe *p) BUG_ON(kprobe_gone(ap) || kprobe_gone(p)); if (p->break_handler || p->post_handler) - unoptimize_kprobe(ap); /* Fall back to normal kprobe */ + unoptimize_kprobe(ap, true); /* Fall back to normal kprobe */ if (p->break_handler) { if (ap->break_handler) @@ -993,19 +1183,21 @@ static void __kprobes init_aggr_kprobe(struct kprobe *ap, struct kprobe *p) * This is the second or subsequent kprobe at the address - handle * the intricacies */ -static int __kprobes register_aggr_kprobe(struct kprobe *old_p, +static int __kprobes register_aggr_kprobe(struct kprobe *orig_p, struct kprobe *p) { int ret = 0; - struct kprobe *ap = old_p; + struct kprobe *ap = orig_p; - if (!kprobe_aggrprobe(old_p)) { - /* If old_p is not an aggr_kprobe, create new aggr_kprobe. */ - ap = alloc_aggr_kprobe(old_p); + if (!kprobe_aggrprobe(orig_p)) { + /* If orig_p is not an aggr_kprobe, create new aggr_kprobe. */ + ap = alloc_aggr_kprobe(orig_p); if (!ap) return -ENOMEM; - init_aggr_kprobe(ap, old_p); - } + init_aggr_kprobe(ap, orig_p); + } else if (kprobe_unused(ap)) + /* This probe is going to die. Rescue it */ + reuse_unused_kprobe(ap); if (kprobe_gone(ap)) { /* @@ -1039,23 +1231,6 @@ static int __kprobes register_aggr_kprobe(struct kprobe *old_p, return add_new_kprobe(ap, p); } -/* Try to disable aggr_kprobe, and return 1 if succeeded.*/ -static int __kprobes try_to_disable_aggr_kprobe(struct kprobe *p) -{ - struct kprobe *kp; - - list_for_each_entry_rcu(kp, &p->list, list) { - if (!kprobe_disabled(kp)) - /* - * There is an active probe on the list. - * We can't disable aggr_kprobe. - */ - return 0; - } - p->flags |= KPROBE_FLAG_DISABLED; - return 1; -} - static int __kprobes in_kprobes_functions(unsigned long addr) { struct kprobe_blackpoint *kb; @@ -1098,34 +1273,33 @@ static kprobe_opcode_t __kprobes *kprobe_addr(struct kprobe *p) /* Check passed kprobe is valid and return kprobe in kprobe_table. */ static struct kprobe * __kprobes __get_valid_kprobe(struct kprobe *p) { - struct kprobe *old_p, *list_p; + struct kprobe *ap, *list_p; - old_p = get_kprobe(p->addr); - if (unlikely(!old_p)) + ap = get_kprobe(p->addr); + if (unlikely(!ap)) return NULL; - if (p != old_p) { - list_for_each_entry_rcu(list_p, &old_p->list, list) + if (p != ap) { + list_for_each_entry_rcu(list_p, &ap->list, list) if (list_p == p) /* kprobe p is a valid probe */ goto valid; return NULL; } valid: - return old_p; + return ap; } /* Return error if the kprobe is being re-registered */ static inline int check_kprobe_rereg(struct kprobe *p) { int ret = 0; - struct kprobe *old_p; mutex_lock(&kprobe_mutex); - old_p = __get_valid_kprobe(p); - if (old_p) + if (__get_valid_kprobe(p)) ret = -EINVAL; mutex_unlock(&kprobe_mutex); + return ret; } @@ -1229,67 +1403,121 @@ fail_with_jump_label: } EXPORT_SYMBOL_GPL(register_kprobe); +/* Check if all probes on the aggrprobe are disabled */ +static int __kprobes aggr_kprobe_disabled(struct kprobe *ap) +{ + struct kprobe *kp; + + list_for_each_entry_rcu(kp, &ap->list, list) + if (!kprobe_disabled(kp)) + /* + * There is an active probe on the list. + * We can't disable this ap. + */ + return 0; + + return 1; +} + +/* Disable one kprobe: Make sure called under kprobe_mutex is locked */ +static struct kprobe *__kprobes __disable_kprobe(struct kprobe *p) +{ + struct kprobe *orig_p; + + /* Get an original kprobe for return */ + orig_p = __get_valid_kprobe(p); + if (unlikely(orig_p == NULL)) + return NULL; + + if (!kprobe_disabled(p)) { + /* Disable probe if it is a child probe */ + if (p != orig_p) + p->flags |= KPROBE_FLAG_DISABLED; + + /* Try to disarm and disable this/parent probe */ + if (p == orig_p || aggr_kprobe_disabled(orig_p)) { + disarm_kprobe(orig_p); + orig_p->flags |= KPROBE_FLAG_DISABLED; + } + } + + return orig_p; +} + /* * Unregister a kprobe without a scheduler synchronization. */ static int __kprobes __unregister_kprobe_top(struct kprobe *p) { - struct kprobe *old_p, *list_p; + struct kprobe *ap, *list_p; - old_p = __get_valid_kprobe(p); - if (old_p == NULL) + /* Disable kprobe. This will disarm it if needed. */ + ap = __disable_kprobe(p); + if (ap == NULL) return -EINVAL; - if (old_p == p || - (kprobe_aggrprobe(old_p) && - list_is_singular(&old_p->list))) { + if (ap == p) /* - * Only probe on the hash list. Disarm only if kprobes are - * enabled and not gone - otherwise, the breakpoint would - * already have been removed. We save on flushing icache. + * This probe is an independent(and non-optimized) kprobe + * (not an aggrprobe). Remove from the hash list. */ - if (!kprobes_all_disarmed && !kprobe_disabled(old_p)) - disarm_kprobe(old_p); - hlist_del_rcu(&old_p->hlist); - } else { + goto disarmed; + + /* Following process expects this probe is an aggrprobe */ + WARN_ON(!kprobe_aggrprobe(ap)); + + if (list_is_singular(&ap->list) && kprobe_disarmed(ap)) + /* + * !disarmed could be happen if the probe is under delayed + * unoptimizing. + */ + goto disarmed; + else { + /* If disabling probe has special handlers, update aggrprobe */ if (p->break_handler && !kprobe_gone(p)) - old_p->break_handler = NULL; + ap->break_handler = NULL; if (p->post_handler && !kprobe_gone(p)) { - list_for_each_entry_rcu(list_p, &old_p->list, list) { + list_for_each_entry_rcu(list_p, &ap->list, list) { if ((list_p != p) && (list_p->post_handler)) goto noclean; } - old_p->post_handler = NULL; + ap->post_handler = NULL; } noclean: + /* + * Remove from the aggrprobe: this path will do nothing in + * __unregister_kprobe_bottom(). + */ list_del_rcu(&p->list); - if (!kprobe_disabled(old_p)) { - try_to_disable_aggr_kprobe(old_p); - if (!kprobes_all_disarmed) { - if (kprobe_disabled(old_p)) - disarm_kprobe(old_p); - else - /* Try to optimize this probe again */ - optimize_kprobe(old_p); - } - } + if (!kprobe_disabled(ap) && !kprobes_all_disarmed) + /* + * Try to optimize this probe again, because post + * handler may have been changed. + */ + optimize_kprobe(ap); } return 0; + +disarmed: + BUG_ON(!kprobe_disarmed(ap)); + hlist_del_rcu(&ap->hlist); + return 0; } static void __kprobes __unregister_kprobe_bottom(struct kprobe *p) { - struct kprobe *old_p; + struct kprobe *ap; if (list_empty(&p->list)) + /* This is an independent kprobe */ arch_remove_kprobe(p); else if (list_is_singular(&p->list)) { - /* "p" is the last child of an aggr_kprobe */ - old_p = list_entry(p->list.next, struct kprobe, list); + /* This is the last child of an aggrprobe */ + ap = list_entry(p->list.next, struct kprobe, list); list_del(&p->list); - arch_remove_kprobe(old_p); - free_aggr_kprobe(old_p); + free_aggr_kprobe(ap); } + /* Otherwise, do nothing. */ } int __kprobes register_kprobes(struct kprobe **kps, int num) @@ -1607,29 +1835,13 @@ static void __kprobes kill_kprobe(struct kprobe *p) int __kprobes disable_kprobe(struct kprobe *kp) { int ret = 0; - struct kprobe *p; mutex_lock(&kprobe_mutex); - /* Check whether specified probe is valid. */ - p = __get_valid_kprobe(kp); - if (unlikely(p == NULL)) { + /* Disable this kprobe */ + if (__disable_kprobe(kp) == NULL) ret = -EINVAL; - goto out; - } - /* If the probe is already disabled (or gone), just return */ - if (kprobe_disabled(kp)) - goto out; - - kp->flags |= KPROBE_FLAG_DISABLED; - if (p != kp) - /* When kp != p, p is always enabled. */ - try_to_disable_aggr_kprobe(p); - - if (!kprobes_all_disarmed && kprobe_disabled(p)) - disarm_kprobe(p); -out: mutex_unlock(&kprobe_mutex); return ret; } @@ -1927,36 +2139,27 @@ static void __kprobes disarm_all_kprobes(void) mutex_lock(&kprobe_mutex); /* If kprobes are already disarmed, just return */ - if (kprobes_all_disarmed) - goto already_disabled; + if (kprobes_all_disarmed) { + mutex_unlock(&kprobe_mutex); + return; + } kprobes_all_disarmed = true; printk(KERN_INFO "Kprobes globally disabled\n"); - /* - * Here we call get_online_cpus() for avoiding text_mutex deadlock, - * because disarming may also unoptimize kprobes. - */ - get_online_cpus(); mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) { if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p)) - __disarm_kprobe(p); + __disarm_kprobe(p, false); } } - mutex_unlock(&text_mutex); - put_online_cpus(); mutex_unlock(&kprobe_mutex); - /* Allow all currently running kprobes to complete */ - synchronize_sched(); - return; -already_disabled: - mutex_unlock(&kprobe_mutex); - return; + /* Wait for disarming all kprobes by optimizer */ + wait_for_kprobe_optimizer(); } /* diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 0b624e79180..3b053c04dd8 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -16,6 +16,7 @@ #include <linux/kexec.h> #include <linux/profile.h> #include <linux/sched.h> +#include <linux/capability.h> #define KERNEL_ATTR_RO(_name) \ static struct kobj_attribute _name##_attr = __ATTR_RO(_name) @@ -131,6 +132,14 @@ KERNEL_ATTR_RO(vmcoreinfo); #endif /* CONFIG_KEXEC */ +/* whether file capabilities are enabled */ +static ssize_t fscaps_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", file_caps_enabled); +} +KERNEL_ATTR_RO(fscaps); + /* * Make /sys/kernel/notes give the raw contents of our kernel .notes section. */ @@ -158,6 +167,7 @@ struct kobject *kernel_kobj; EXPORT_SYMBOL_GPL(kernel_kobj); static struct attribute * kernel_attrs[] = { + &fscaps_attr.attr, #if defined(CONFIG_HOTPLUG) &uevent_seqnum_attr.attr, &uevent_helper_attr.attr, diff --git a/kernel/kthread.c b/kernel/kthread.c index 2dc3786349d..3b34d2732bc 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -27,6 +27,7 @@ struct kthread_create_info /* Information passed to kthread() from kthreadd. */ int (*threadfn)(void *data); void *data; + int node; /* Result passed back to kthread_create() from kthreadd. */ struct task_struct *result; @@ -98,10 +99,23 @@ static int kthread(void *_create) do_exit(ret); } +/* called from do_fork() to get node information for about to be created task */ +int tsk_fork_get_node(struct task_struct *tsk) +{ +#ifdef CONFIG_NUMA + if (tsk == kthreadd_task) + return tsk->pref_node_fork; +#endif + return numa_node_id(); +} + static void create_kthread(struct kthread_create_info *create) { int pid; +#ifdef CONFIG_NUMA + current->pref_node_fork = create->node; +#endif /* We want our own signal handler (we take no signals by default). */ pid = kernel_thread(kthread, create, CLONE_FS | CLONE_FILES | SIGCHLD); if (pid < 0) { @@ -111,33 +125,38 @@ static void create_kthread(struct kthread_create_info *create) } /** - * kthread_create - create a kthread. + * kthread_create_on_node - create a kthread. * @threadfn: the function to run until signal_pending(current). * @data: data ptr for @threadfn. + * @node: memory node number. * @namefmt: printf-style name for the thread. * * Description: This helper function creates and names a kernel * thread. The thread will be stopped: use wake_up_process() to start * it. See also kthread_run(). * + * If thread is going to be bound on a particular cpu, give its node + * in @node, to get NUMA affinity for kthread stack, or else give -1. * When woken, the thread will run @threadfn() with @data as its * argument. @threadfn() can either call do_exit() directly if it is a - * standalone thread for which noone will call kthread_stop(), or + * standalone thread for which no one will call kthread_stop(), or * return when 'kthread_should_stop()' is true (which means * kthread_stop() has been called). The return value should be zero * or a negative error number; it will be passed to kthread_stop(). * * Returns a task_struct or ERR_PTR(-ENOMEM). */ -struct task_struct *kthread_create(int (*threadfn)(void *data), - void *data, - const char namefmt[], - ...) +struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), + void *data, + int node, + const char namefmt[], + ...) { struct kthread_create_info create; create.threadfn = threadfn; create.data = data; + create.node = node; init_completion(&create.done); spin_lock(&kthread_create_lock); @@ -148,7 +167,7 @@ struct task_struct *kthread_create(int (*threadfn)(void *data), wait_for_completion(&create.done); if (!IS_ERR(create.result)) { - struct sched_param param = { .sched_priority = 0 }; + static const struct sched_param param = { .sched_priority = 0 }; va_list args; va_start(args, namefmt); @@ -164,7 +183,7 @@ struct task_struct *kthread_create(int (*threadfn)(void *data), } return create.result; } -EXPORT_SYMBOL(kthread_create); +EXPORT_SYMBOL(kthread_create_on_node); /** * kthread_bind - bind a just-created kthread to a cpu. @@ -265,6 +284,17 @@ int kthreadd(void *unused) return 0; } +void __init_kthread_worker(struct kthread_worker *worker, + const char *name, + struct lock_class_key *key) +{ + spin_lock_init(&worker->lock); + lockdep_set_class_and_name(&worker->lock, key, name); + INIT_LIST_HEAD(&worker->work_list); + worker->task = NULL; +} +EXPORT_SYMBOL_GPL(__init_kthread_worker); + /** * kthread_worker_fn - kthread function to process kthread_worker * @worker_ptr: pointer to initialized kthread_worker diff --git a/kernel/latencytop.c b/kernel/latencytop.c index 877fb306d41..376066e1041 100644 --- a/kernel/latencytop.c +++ b/kernel/latencytop.c @@ -153,7 +153,7 @@ static inline void store_stacktrace(struct task_struct *tsk, } /** - * __account_scheduler_latency - record an occured latency + * __account_scheduler_latency - record an occurred latency * @tsk - the task struct of the task hitting the latency * @usecs - the duration of the latency in microseconds * @inter - 1 if the sleep was interruptible, 0 if uninterruptible @@ -194,14 +194,7 @@ __account_scheduler_latency(struct task_struct *tsk, int usecs, int inter) account_global_scheduler_latency(tsk, &lat); - /* - * short term hack; if we're > 32 we stop; future we recycle: - */ - tsk->latency_record_count++; - if (tsk->latency_record_count >= LT_SAVECOUNT) - goto out_unlock; - - for (i = 0; i < LT_SAVECOUNT; i++) { + for (i = 0; i < tsk->latency_record_count; i++) { struct latency_record *mylat; int same = 1; @@ -227,8 +220,14 @@ __account_scheduler_latency(struct task_struct *tsk, int usecs, int inter) } } + /* + * short term hack; if we're > 32 we stop; future we recycle: + */ + if (tsk->latency_record_count >= LT_SAVECOUNT) + goto out_unlock; + /* Allocated a new one: */ - i = tsk->latency_record_count; + i = tsk->latency_record_count++; memcpy(&tsk->latency_record[i], &lat, sizeof(struct latency_record)); out_unlock: @@ -242,24 +241,19 @@ static int lstats_show(struct seq_file *m, void *v) seq_puts(m, "Latency Top version : v0.1\n"); for (i = 0; i < MAXLR; i++) { - if (latency_record[i].backtrace[0]) { + struct latency_record *lr = &latency_record[i]; + + if (lr->backtrace[0]) { int q; - seq_printf(m, "%i %lu %lu ", - latency_record[i].count, - latency_record[i].time, - latency_record[i].max); + seq_printf(m, "%i %lu %lu", + lr->count, lr->time, lr->max); for (q = 0; q < LT_BACKTRACEDEPTH; q++) { - char sym[KSYM_SYMBOL_LEN]; - char *c; - if (!latency_record[i].backtrace[q]) + unsigned long bt = lr->backtrace[q]; + if (!bt) break; - if (latency_record[i].backtrace[q] == ULONG_MAX) + if (bt == ULONG_MAX) break; - sprint_symbol(sym, latency_record[i].backtrace[q]); - c = strchr(sym, '+'); - if (c) - *c = 0; - seq_printf(m, "%s ", sym); + seq_printf(m, " %ps", (void *)bt); } seq_printf(m, "\n"); } diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 42ba65dff7d..63437d065ac 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -490,6 +490,18 @@ void get_usage_chars(struct lock_class *class, char usage[LOCK_USAGE_CHARS]) usage[i] = '\0'; } +static int __print_lock_name(struct lock_class *class) +{ + char str[KSYM_NAME_LEN]; + const char *name; + + name = class->name; + if (!name) + name = __get_key_name(class->key, str); + + return printk("%s", name); +} + static void print_lock_name(struct lock_class *class) { char str[KSYM_NAME_LEN], usage[LOCK_USAGE_CHARS]; @@ -1053,6 +1065,56 @@ print_circular_bug_entry(struct lock_list *target, int depth) return 0; } +static void +print_circular_lock_scenario(struct held_lock *src, + struct held_lock *tgt, + struct lock_list *prt) +{ + struct lock_class *source = hlock_class(src); + struct lock_class *target = hlock_class(tgt); + struct lock_class *parent = prt->class; + + /* + * A direct locking problem where unsafe_class lock is taken + * directly by safe_class lock, then all we need to show + * is the deadlock scenario, as it is obvious that the + * unsafe lock is taken under the safe lock. + * + * But if there is a chain instead, where the safe lock takes + * an intermediate lock (middle_class) where this lock is + * not the same as the safe lock, then the lock chain is + * used to describe the problem. Otherwise we would need + * to show a different CPU case for each link in the chain + * from the safe_class lock to the unsafe_class lock. + */ + if (parent != source) { + printk("Chain exists of:\n "); + __print_lock_name(source); + printk(" --> "); + __print_lock_name(parent); + printk(" --> "); + __print_lock_name(target); + printk("\n\n"); + } + + printk(" Possible unsafe locking scenario:\n\n"); + printk(" CPU0 CPU1\n"); + printk(" ---- ----\n"); + printk(" lock("); + __print_lock_name(target); + printk(");\n"); + printk(" lock("); + __print_lock_name(parent); + printk(");\n"); + printk(" lock("); + __print_lock_name(target); + printk(");\n"); + printk(" lock("); + __print_lock_name(source); + printk(");\n"); + printk("\n *** DEADLOCK ***\n\n"); +} + /* * When a circular dependency is detected, print the * header first: @@ -1096,6 +1158,7 @@ static noinline int print_circular_bug(struct lock_list *this, { struct task_struct *curr = current; struct lock_list *parent; + struct lock_list *first_parent; int depth; if (!debug_locks_off_graph_unlock() || debug_locks_silent) @@ -1109,6 +1172,7 @@ static noinline int print_circular_bug(struct lock_list *this, print_circular_bug_header(target, depth, check_src, check_tgt); parent = get_lock_parent(target); + first_parent = parent; while (parent) { print_circular_bug_entry(parent, --depth); @@ -1116,6 +1180,9 @@ static noinline int print_circular_bug(struct lock_list *this, } printk("\nother info that might help us debug this:\n\n"); + print_circular_lock_scenario(check_src, check_tgt, + first_parent); + lockdep_print_held_locks(curr); printk("\nstack backtrace:\n"); @@ -1314,7 +1381,7 @@ print_shortest_lock_dependencies(struct lock_list *leaf, printk("\n"); if (depth == 0 && (entry != root)) { - printk("lockdep:%s bad BFS generated tree\n", __func__); + printk("lockdep:%s bad path found in chain graph\n", __func__); break; } @@ -1325,6 +1392,62 @@ print_shortest_lock_dependencies(struct lock_list *leaf, return; } +static void +print_irq_lock_scenario(struct lock_list *safe_entry, + struct lock_list *unsafe_entry, + struct lock_class *prev_class, + struct lock_class *next_class) +{ + struct lock_class *safe_class = safe_entry->class; + struct lock_class *unsafe_class = unsafe_entry->class; + struct lock_class *middle_class = prev_class; + + if (middle_class == safe_class) + middle_class = next_class; + + /* + * A direct locking problem where unsafe_class lock is taken + * directly by safe_class lock, then all we need to show + * is the deadlock scenario, as it is obvious that the + * unsafe lock is taken under the safe lock. + * + * But if there is a chain instead, where the safe lock takes + * an intermediate lock (middle_class) where this lock is + * not the same as the safe lock, then the lock chain is + * used to describe the problem. Otherwise we would need + * to show a different CPU case for each link in the chain + * from the safe_class lock to the unsafe_class lock. + */ + if (middle_class != unsafe_class) { + printk("Chain exists of:\n "); + __print_lock_name(safe_class); + printk(" --> "); + __print_lock_name(middle_class); + printk(" --> "); + __print_lock_name(unsafe_class); + printk("\n\n"); + } + + printk(" Possible interrupt unsafe locking scenario:\n\n"); + printk(" CPU0 CPU1\n"); + printk(" ---- ----\n"); + printk(" lock("); + __print_lock_name(unsafe_class); + printk(");\n"); + printk(" local_irq_disable();\n"); + printk(" lock("); + __print_lock_name(safe_class); + printk(");\n"); + printk(" lock("); + __print_lock_name(middle_class); + printk(");\n"); + printk(" <Interrupt>\n"); + printk(" lock("); + __print_lock_name(safe_class); + printk(");\n"); + printk("\n *** DEADLOCK ***\n\n"); +} + static int print_bad_irq_dependency(struct task_struct *curr, struct lock_list *prev_root, @@ -1376,6 +1499,9 @@ print_bad_irq_dependency(struct task_struct *curr, print_stack_trace(forwards_entry->class->usage_traces + bit2, 1); printk("\nother info that might help us debug this:\n\n"); + print_irq_lock_scenario(backwards_entry, forwards_entry, + hlock_class(prev), hlock_class(next)); + lockdep_print_held_locks(curr); printk("\nthe dependencies between %s-irq-safe lock", irqclass); @@ -1539,6 +1665,26 @@ static inline void inc_chains(void) #endif +static void +print_deadlock_scenario(struct held_lock *nxt, + struct held_lock *prv) +{ + struct lock_class *next = hlock_class(nxt); + struct lock_class *prev = hlock_class(prv); + + printk(" Possible unsafe locking scenario:\n\n"); + printk(" CPU0\n"); + printk(" ----\n"); + printk(" lock("); + __print_lock_name(prev); + printk(");\n"); + printk(" lock("); + __print_lock_name(next); + printk(");\n"); + printk("\n *** DEADLOCK ***\n\n"); + printk(" May be due to missing lock nesting notation\n\n"); +} + static int print_deadlock_bug(struct task_struct *curr, struct held_lock *prev, struct held_lock *next) @@ -1557,6 +1703,7 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev, print_lock(prev); printk("\nother info that might help us debug this:\n"); + print_deadlock_scenario(next, prev); lockdep_print_held_locks(curr); printk("\nstack backtrace:\n"); @@ -1826,7 +1973,7 @@ static inline int lookup_chain_cache(struct task_struct *curr, struct list_head *hash_head = chainhashentry(chain_key); struct lock_chain *chain; struct held_lock *hlock_curr, *hlock_next; - int i, j, n, cn; + int i, j; if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) return 0; @@ -1886,15 +2033,9 @@ cache_hit: } i++; chain->depth = curr->lockdep_depth + 1 - i; - cn = nr_chain_hlocks; - while (cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS) { - n = cmpxchg(&nr_chain_hlocks, cn, cn + chain->depth); - if (n == cn) - break; - cn = n; - } - if (likely(cn + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) { - chain->base = cn; + if (likely(nr_chain_hlocks + chain->depth <= MAX_LOCKDEP_CHAIN_HLOCKS)) { + chain->base = nr_chain_hlocks; + nr_chain_hlocks += chain->depth; for (j = 0; j < chain->depth - 1; j++, i++) { int lock_id = curr->held_locks[i].class_idx - 1; chain_hlocks[chain->base + j] = lock_id; @@ -2011,6 +2152,24 @@ static void check_chain_key(struct task_struct *curr) #endif } +static void +print_usage_bug_scenario(struct held_lock *lock) +{ + struct lock_class *class = hlock_class(lock); + + printk(" Possible unsafe locking scenario:\n\n"); + printk(" CPU0\n"); + printk(" ----\n"); + printk(" lock("); + __print_lock_name(class); + printk(");\n"); + printk(" <Interrupt>\n"); + printk(" lock("); + __print_lock_name(class); + printk(");\n"); + printk("\n *** DEADLOCK ***\n\n"); +} + static int print_usage_bug(struct task_struct *curr, struct held_lock *this, enum lock_usage_bit prev_bit, enum lock_usage_bit new_bit) @@ -2039,6 +2198,8 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this, print_irqtrace_events(curr); printk("\nother info that might help us debug this:\n"); + print_usage_bug_scenario(this); + lockdep_print_held_locks(curr); printk("\nstack backtrace:\n"); @@ -2073,6 +2234,10 @@ print_irq_inversion_bug(struct task_struct *curr, struct held_lock *this, int forwards, const char *irqclass) { + struct lock_list *entry = other; + struct lock_list *middle = NULL; + int depth; + if (!debug_locks_off_graph_unlock() || debug_locks_silent) return 0; @@ -2091,6 +2256,25 @@ print_irq_inversion_bug(struct task_struct *curr, printk("\n\nand interrupts could create inverse lock ordering between them.\n\n"); printk("\nother info that might help us debug this:\n"); + + /* Find a middle lock (if one exists) */ + depth = get_lock_depth(other); + do { + if (depth == 0 && (entry != root)) { + printk("lockdep:%s bad path found in chain graph\n", __func__); + break; + } + middle = entry; + entry = get_lock_parent(entry); + depth--; + } while (entry && entry != root && (depth >= 0)); + if (forwards) + print_irq_lock_scenario(root, other, + middle ? middle->class : root->class, other->class); + else + print_irq_lock_scenario(other, root, + middle ? middle->class : other->class, root->class); + lockdep_print_held_locks(curr); printk("\nthe shortest dependencies between 2nd lock and 1st lock:\n"); @@ -2292,22 +2476,6 @@ mark_held_locks(struct task_struct *curr, enum mark_type mark) } /* - * Debugging helper: via this flag we know that we are in - * 'early bootup code', and will warn about any invalid irqs-on event: - */ -static int early_boot_irqs_enabled; - -void early_boot_irqs_off(void) -{ - early_boot_irqs_enabled = 0; -} - -void early_boot_irqs_on(void) -{ - early_boot_irqs_enabled = 1; -} - -/* * Hardirqs will be enabled: */ void trace_hardirqs_on_caller(unsigned long ip) @@ -2319,13 +2487,13 @@ void trace_hardirqs_on_caller(unsigned long ip) if (unlikely(!debug_locks || current->lockdep_recursion)) return; - if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled))) + if (DEBUG_LOCKS_WARN_ON(unlikely(early_boot_irqs_disabled))) return; if (unlikely(curr->hardirqs_enabled)) { /* * Neither irq nor preemption are disabled here - * so this is racy by nature but loosing one hit + * so this is racy by nature but losing one hit * in a stat is not a big deal. */ __debug_atomic_inc(redundant_hardirqs_on); @@ -2636,7 +2804,7 @@ static int mark_lock(struct task_struct *curr, struct held_lock *this, if (!graph_lock()) return 0; /* - * Make sure we didnt race: + * Make sure we didn't race: */ if (unlikely(hlock_class(this)->usage_mask & new_mask)) { graph_unlock(); diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c index 59b76c8ce9d..71edd2f60c0 100644 --- a/kernel/lockdep_proc.c +++ b/kernel/lockdep_proc.c @@ -225,7 +225,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v) nr_irq_read_safe = 0, nr_irq_read_unsafe = 0, nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0, nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0, - sum_forward_deps = 0, factor = 0; + sum_forward_deps = 0; list_for_each_entry(class, &all_lock_classes, lock_entry) { @@ -283,13 +283,6 @@ static int lockdep_stats_show(struct seq_file *m, void *v) nr_hardirq_unsafe * nr_hardirq_safe + nr_list_entries); - /* - * Estimated factor between direct and indirect - * dependencies: - */ - if (nr_list_entries) - factor = sum_forward_deps / nr_list_entries; - #ifdef CONFIG_PROVE_LOCKING seq_printf(m, " dependency chains: %11lu [max: %lu]\n", nr_lock_chains, MAX_LOCKDEP_CHAINS); @@ -494,7 +487,6 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data) namelen += 2; for (i = 0; i < LOCKSTAT_POINTS; i++) { - char sym[KSYM_SYMBOL_LEN]; char ip[32]; if (class->contention_point[i] == 0) @@ -503,15 +495,13 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data) if (!i) seq_line(m, '-', 40-namelen, namelen); - sprint_symbol(sym, class->contention_point[i]); snprintf(ip, sizeof(ip), "[<%p>]", (void *)class->contention_point[i]); - seq_printf(m, "%40s %14lu %29s %s\n", name, - stats->contention_point[i], - ip, sym); + seq_printf(m, "%40s %14lu %29s %pS\n", + name, stats->contention_point[i], + ip, (void *)class->contention_point[i]); } for (i = 0; i < LOCKSTAT_POINTS; i++) { - char sym[KSYM_SYMBOL_LEN]; char ip[32]; if (class->contending_point[i] == 0) @@ -520,12 +510,11 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data) if (!i) seq_line(m, '-', 40-namelen, namelen); - sprint_symbol(sym, class->contending_point[i]); snprintf(ip, sizeof(ip), "[<%p>]", (void *)class->contending_point[i]); - seq_printf(m, "%40s %14lu %29s %s\n", name, - stats->contending_point[i], - ip, sym); + seq_printf(m, "%40s %14lu %29s %pS\n", + name, stats->contending_point[i], + ip, (void *)class->contending_point[i]); } if (i) { seq_puts(m, "\n"); diff --git a/kernel/module.c b/kernel/module.c index 437a74a7524..22879725678 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -56,6 +56,8 @@ #include <linux/percpu.h> #include <linux/kmemleak.h> #include <linux/jump_label.h> +#include <linux/pfn.h> +#include <linux/bsearch.h> #define CREATE_TRACE_POINTS #include <trace/events/module.h> @@ -70,6 +72,26 @@ #define ARCH_SHF_SMALL 0 #endif +/* + * Modules' sections will be aligned on page boundaries + * to ensure complete separation of code and data, but + * only when CONFIG_DEBUG_SET_MODULE_RONX=y + */ +#ifdef CONFIG_DEBUG_SET_MODULE_RONX +# define debug_align(X) ALIGN(X, PAGE_SIZE) +#else +# define debug_align(X) (X) +#endif + +/* + * Given BASE and SIZE this macro calculates the number of pages the + * memory regions occupies + */ +#define MOD_NUMBER_OF_PAGES(BASE, SIZE) (((SIZE) > 0) ? \ + (PFN_DOWN((unsigned long)(BASE) + (SIZE) - 1) - \ + PFN_DOWN((unsigned long)BASE) + 1) \ + : (0UL)) + /* If this is set, the section belongs in the init part of the module */ #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) @@ -219,23 +241,24 @@ static bool each_symbol_in_section(const struct symsearch *arr, struct module *owner, bool (*fn)(const struct symsearch *syms, struct module *owner, - unsigned int symnum, void *data), + void *data), void *data) { - unsigned int i, j; + unsigned int j; for (j = 0; j < arrsize; j++) { - for (i = 0; i < arr[j].stop - arr[j].start; i++) - if (fn(&arr[j], owner, i, data)) - return true; + if (fn(&arr[j], owner, data)) + return true; } return false; } /* Returns true as soon as fn returns true, otherwise false. */ -bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner, - unsigned int symnum, void *data), void *data) +bool each_symbol_section(bool (*fn)(const struct symsearch *arr, + struct module *owner, + void *data), + void *data) { struct module *mod; static const struct symsearch arr[] = { @@ -288,7 +311,7 @@ bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner, } return false; } -EXPORT_SYMBOL_GPL(each_symbol); +EXPORT_SYMBOL_GPL(each_symbol_section); struct find_symbol_arg { /* Input */ @@ -302,15 +325,12 @@ struct find_symbol_arg { const struct kernel_symbol *sym; }; -static bool find_symbol_in_section(const struct symsearch *syms, - struct module *owner, - unsigned int symnum, void *data) +static bool check_symbol(const struct symsearch *syms, + struct module *owner, + unsigned int symnum, void *data) { struct find_symbol_arg *fsa = data; - if (strcmp(syms->start[symnum].name, fsa->name) != 0) - return false; - if (!fsa->gplok) { if (syms->licence == GPL_ONLY) return false; @@ -344,6 +364,30 @@ static bool find_symbol_in_section(const struct symsearch *syms, return true; } +static int cmp_name(const void *va, const void *vb) +{ + const char *a; + const struct kernel_symbol *b; + a = va; b = vb; + return strcmp(a, b->name); +} + +static bool find_symbol_in_section(const struct symsearch *syms, + struct module *owner, + void *data) +{ + struct find_symbol_arg *fsa = data; + struct kernel_symbol *sym; + + sym = bsearch(fsa->name, syms->start, syms->stop - syms->start, + sizeof(struct kernel_symbol), cmp_name); + + if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data)) + return true; + + return false; +} + /* Find a symbol and return it, along with, (optional) crc and * (optional) module which owns it. Needs preempt disabled or module_mutex. */ const struct kernel_symbol *find_symbol(const char *name, @@ -358,7 +402,7 @@ const struct kernel_symbol *find_symbol(const char *name, fsa.gplok = gplok; fsa.warn = warn; - if (each_symbol(find_symbol_in_section, &fsa)) { + if (each_symbol_section(find_symbol_in_section, &fsa)) { if (owner) *owner = fsa.owner; if (crc) @@ -788,7 +832,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, wait_for_zero_refcount(mod); mutex_unlock(&module_mutex); - /* Final destruction now noone is using it. */ + /* Final destruction now no one is using it. */ if (mod->exit != NULL) mod->exit(); blocking_notifier_call_chain(&module_notify_list, @@ -1147,7 +1191,7 @@ static ssize_t module_sect_show(struct module_attribute *mattr, { struct module_sect_attr *sattr = container_of(mattr, struct module_sect_attr, mattr); - return sprintf(buf, "0x%lx\n", sattr->address); + return sprintf(buf, "0x%pK\n", (void *)sattr->address); } static void free_sect_attrs(struct module_sect_attrs *sect_attrs) @@ -1542,6 +1586,117 @@ static int __unlink_module(void *_mod) return 0; } +#ifdef CONFIG_DEBUG_SET_MODULE_RONX +/* + * LKM RO/NX protection: protect module's text/ro-data + * from modification and any data from execution. + */ +void set_page_attributes(void *start, void *end, int (*set)(unsigned long start, int num_pages)) +{ + unsigned long begin_pfn = PFN_DOWN((unsigned long)start); + unsigned long end_pfn = PFN_DOWN((unsigned long)end); + + if (end_pfn > begin_pfn) + set(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn); +} + +static void set_section_ro_nx(void *base, + unsigned long text_size, + unsigned long ro_size, + unsigned long total_size) +{ + /* begin and end PFNs of the current subsection */ + unsigned long begin_pfn; + unsigned long end_pfn; + + /* + * Set RO for module text and RO-data: + * - Always protect first page. + * - Do not protect last partial page. + */ + if (ro_size > 0) + set_page_attributes(base, base + ro_size, set_memory_ro); + + /* + * Set NX permissions for module data: + * - Do not protect first partial page. + * - Always protect last page. + */ + if (total_size > text_size) { + begin_pfn = PFN_UP((unsigned long)base + text_size); + end_pfn = PFN_UP((unsigned long)base + total_size); + if (end_pfn > begin_pfn) + set_memory_nx(begin_pfn << PAGE_SHIFT, end_pfn - begin_pfn); + } +} + +static void unset_module_core_ro_nx(struct module *mod) +{ + set_page_attributes(mod->module_core + mod->core_text_size, + mod->module_core + mod->core_size, + set_memory_x); + set_page_attributes(mod->module_core, + mod->module_core + mod->core_ro_size, + set_memory_rw); +} + +static void unset_module_init_ro_nx(struct module *mod) +{ + set_page_attributes(mod->module_init + mod->init_text_size, + mod->module_init + mod->init_size, + set_memory_x); + set_page_attributes(mod->module_init, + mod->module_init + mod->init_ro_size, + set_memory_rw); +} + +/* Iterate through all modules and set each module's text as RW */ +void set_all_modules_text_rw(void) +{ + struct module *mod; + + mutex_lock(&module_mutex); + list_for_each_entry_rcu(mod, &modules, list) { + if ((mod->module_core) && (mod->core_text_size)) { + set_page_attributes(mod->module_core, + mod->module_core + mod->core_text_size, + set_memory_rw); + } + if ((mod->module_init) && (mod->init_text_size)) { + set_page_attributes(mod->module_init, + mod->module_init + mod->init_text_size, + set_memory_rw); + } + } + mutex_unlock(&module_mutex); +} + +/* Iterate through all modules and set each module's text as RO */ +void set_all_modules_text_ro(void) +{ + struct module *mod; + + mutex_lock(&module_mutex); + list_for_each_entry_rcu(mod, &modules, list) { + if ((mod->module_core) && (mod->core_text_size)) { + set_page_attributes(mod->module_core, + mod->module_core + mod->core_text_size, + set_memory_ro); + } + if ((mod->module_init) && (mod->init_text_size)) { + set_page_attributes(mod->module_init, + mod->module_init + mod->init_text_size, + set_memory_ro); + } + } + mutex_unlock(&module_mutex); +} +#else +static inline void set_section_ro_nx(void *base, unsigned long text_size, unsigned long ro_size, unsigned long total_size) { } +static void unset_module_core_ro_nx(struct module *mod) { } +static void unset_module_init_ro_nx(struct module *mod) { } +#endif + /* Free a module, remove from lists, etc. */ static void free_module(struct module *mod) { @@ -1566,6 +1721,7 @@ static void free_module(struct module *mod) destroy_params(mod->kp, mod->num_kp); /* This may be NULL, but that's OK */ + unset_module_init_ro_nx(mod); module_free(mod, mod->module_init); kfree(mod->args); percpu_modfree(mod); @@ -1574,6 +1730,7 @@ static void free_module(struct module *mod) lockdep_free_key_range(mod->module_core, mod->core_size); /* Finally, free the core (containing the module structure) */ + unset_module_core_ro_nx(mod); module_free(mod, mod->module_core); #ifdef CONFIG_MPU @@ -1777,8 +1934,19 @@ static void layout_sections(struct module *mod, struct load_info *info) s->sh_entsize = get_offset(mod, &mod->core_size, s, i); DEBUGP("\t%s\n", name); } - if (m == 0) + switch (m) { + case 0: /* executable */ + mod->core_size = debug_align(mod->core_size); mod->core_text_size = mod->core_size; + break; + case 1: /* RO: text and ro-data */ + mod->core_size = debug_align(mod->core_size); + mod->core_ro_size = mod->core_size; + break; + case 3: /* whole core */ + mod->core_size = debug_align(mod->core_size); + break; + } } DEBUGP("Init section allocation order:\n"); @@ -1796,8 +1964,19 @@ static void layout_sections(struct module *mod, struct load_info *info) | INIT_OFFSET_MASK); DEBUGP("\t%s\n", sname); } - if (m == 0) + switch (m) { + case 0: /* executable */ + mod->init_size = debug_align(mod->init_size); mod->init_text_size = mod->init_size; + break; + case 1: /* RO: text and ro-data */ + mod->init_size = debug_align(mod->init_size); + mod->init_ro_size = mod->init_size; + break; + case 3: /* whole init */ + mod->init_size = debug_align(mod->init_size); + break; + } } } @@ -1876,11 +2055,8 @@ static const struct kernel_symbol *lookup_symbol(const char *name, const struct kernel_symbol *start, const struct kernel_symbol *stop) { - const struct kernel_symbol *ks = start; - for (; ks < stop; ks++) - if (strcmp(ks->name, name) == 0) - return ks; - return NULL; + return bsearch(name, start, stop - start, + sizeof(struct kernel_symbol), cmp_name); } static int is_exported(const char *name, unsigned long value, @@ -2306,9 +2482,9 @@ static void find_module_sections(struct module *mod, struct load_info *info) #endif #ifdef CONFIG_TRACEPOINTS - mod->tracepoints = section_objs(info, "__tracepoints", - sizeof(*mod->tracepoints), - &mod->num_tracepoints); + mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs", + sizeof(*mod->tracepoints_ptrs), + &mod->num_tracepoints); #endif #ifdef HAVE_JUMP_LABEL mod->jump_entries = section_objs(info, "__jump_table", @@ -2326,6 +2502,18 @@ static void find_module_sections(struct module *mod, struct load_info *info) kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) * mod->num_trace_events, GFP_KERNEL); #endif +#ifdef CONFIG_TRACING + mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt", + sizeof(*mod->trace_bprintk_fmt_start), + &mod->num_trace_bprintk_fmt); + /* + * This section contains pointers to allocated objects in the trace + * code and not scanning it leads to false positives. + */ + kmemleak_scan_area(mod->trace_bprintk_fmt_start, + sizeof(*mod->trace_bprintk_fmt_start) * + mod->num_trace_bprintk_fmt, GFP_KERNEL); +#endif #ifdef CONFIG_FTRACE_MCOUNT_RECORD /* sechdrs[0].sh_size is always zero */ mod->ftrace_callsites = section_objs(info, "__mcount_loc", @@ -2611,7 +2799,7 @@ static struct module *load_module(void __user *umod, mod->state = MODULE_STATE_COMING; /* Now sew it into the lists so we can get lockdep and oops - * info during argument parsing. Noone should access us, since + * info during argument parsing. No one should access us, since * strong_try_module_get() will fail. * lockdep/oops can run asynchronous, so use the RCU list insertion * function to insert in a way safe to concurrent readers. @@ -2710,6 +2898,18 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_COMING, mod); + /* Set RO and NX regions for core */ + set_section_ro_nx(mod->module_core, + mod->core_text_size, + mod->core_ro_size, + mod->core_size); + + /* Set RO and NX regions for init */ + set_section_ro_nx(mod->module_init, + mod->init_text_size, + mod->init_ro_size, + mod->init_size); + do_mod_ctors(mod); /* Start the module */ if (mod->init != NULL) @@ -2753,9 +2953,11 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, mod->symtab = mod->core_symtab; mod->strtab = mod->core_strtab; #endif + unset_module_init_ro_nx(mod); module_free(mod, mod->module_init); mod->module_init = NULL; mod->init_size = 0; + mod->init_ro_size = 0; mod->init_text_size = 0; mutex_unlock(&module_mutex); @@ -2792,7 +2994,7 @@ static const char *get_ksymbol(struct module *mod, else nextval = (unsigned long)mod->module_core+mod->core_text_size; - /* Scan for closest preceeding symbol, and next symbol. (ELF + /* Scan for closest preceding symbol, and next symbol. (ELF starts real symbols at 1). */ for (i = 1; i < mod->num_symtab; i++) { if (mod->symtab[i].st_shndx == SHN_UNDEF) @@ -3045,7 +3247,7 @@ static int m_show(struct seq_file *m, void *p) mod->state == MODULE_STATE_COMING ? "Loading": "Live"); /* Used by oprofile and other similar tools. */ - seq_printf(m, " 0x%p", mod->module_core); + seq_printf(m, " 0x%pK", mod->module_core); /* Taints info */ if (mod->taints) @@ -3214,7 +3416,7 @@ void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp, struct kernel_symbol *ks, - struct tracepoint *tp) + struct tracepoint * const *tp) { } EXPORT_SYMBOL(module_layout); @@ -3228,8 +3430,8 @@ void module_update_tracepoints(void) mutex_lock(&module_mutex); list_for_each_entry(mod, &modules, list) if (!mod->taints) - tracepoint_update_probe_range(mod->tracepoints, - mod->tracepoints + mod->num_tracepoints); + tracepoint_update_probe_range(mod->tracepoints_ptrs, + mod->tracepoints_ptrs + mod->num_tracepoints); mutex_unlock(&module_mutex); } @@ -3253,8 +3455,8 @@ int module_get_iter_tracepoints(struct tracepoint_iter *iter) else if (iter_mod > iter->module) iter->tracepoint = NULL; found = tracepoint_get_iter_range(&iter->tracepoint, - iter_mod->tracepoints, - iter_mod->tracepoints + iter_mod->tracepoints_ptrs, + iter_mod->tracepoints_ptrs + iter_mod->num_tracepoints); if (found) { iter->module = iter_mod; diff --git a/kernel/mutex-debug.c b/kernel/mutex-debug.c index ec815a960b5..73da83aff41 100644 --- a/kernel/mutex-debug.c +++ b/kernel/mutex-debug.c @@ -75,7 +75,7 @@ void debug_mutex_unlock(struct mutex *lock) return; DEBUG_LOCKS_WARN_ON(lock->magic != lock); - DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); + DEBUG_LOCKS_WARN_ON(lock->owner != current); DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next); mutex_clear_owner(lock); } diff --git a/kernel/mutex-debug.h b/kernel/mutex-debug.h index 57d527a16f9..0799fd3e4cf 100644 --- a/kernel/mutex-debug.h +++ b/kernel/mutex-debug.h @@ -29,7 +29,7 @@ extern void debug_mutex_init(struct mutex *lock, const char *name, static inline void mutex_set_owner(struct mutex *lock) { - lock->owner = current_thread_info(); + lock->owner = current; } static inline void mutex_clear_owner(struct mutex *lock) diff --git a/kernel/mutex.c b/kernel/mutex.c index 200407c1502..2c938e2337c 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -160,14 +160,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, */ for (;;) { - struct thread_info *owner; - - /* - * If we own the BKL, then don't spin. The owner of - * the mutex might be waiting on us to release the BKL. - */ - if (unlikely(current->lock_depth >= 0)) - break; + struct task_struct *owner; /* * If there's an owner, wait for it to either @@ -199,7 +192,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, * memory barriers as we'll eventually observe the right * values at the cost of a few extra spins. */ - cpu_relax(); + arch_mutex_cpu_relax(); } #endif spin_lock_mutex(&lock->wait_lock, flags); @@ -245,7 +238,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, } __set_task_state(task, state); - /* didnt get the lock, go to sleep: */ + /* didn't get the lock, go to sleep: */ spin_unlock_mutex(&lock->wait_lock, flags); preempt_enable_no_resched(); schedule(); diff --git a/kernel/mutex.h b/kernel/mutex.h index 67578ca48f9..4115fbf83b1 100644 --- a/kernel/mutex.h +++ b/kernel/mutex.h @@ -19,7 +19,7 @@ #ifdef CONFIG_SMP static inline void mutex_set_owner(struct mutex *lock) { - lock->owner = current_thread_info(); + lock->owner = current; } static inline void mutex_clear_owner(struct mutex *lock) diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index f74e6c00e26..a05d191ffdd 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -69,13 +69,13 @@ static struct nsproxy *create_new_namespaces(unsigned long flags, goto out_ns; } - new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns); + new_nsp->uts_ns = copy_utsname(flags, tsk); if (IS_ERR(new_nsp->uts_ns)) { err = PTR_ERR(new_nsp->uts_ns); goto out_uts; } - new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns); + new_nsp->ipc_ns = copy_ipcs(flags, tsk); if (IS_ERR(new_nsp->ipc_ns)) { err = PTR_ERR(new_nsp->ipc_ns); goto out_ipc; diff --git a/kernel/padata.c b/kernel/padata.c index 751019415d2..b91941df5e6 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -262,7 +262,7 @@ static void padata_reorder(struct parallel_data *pd) /* * This cpu has to do the parallel processing of the next * object. It's waiting in the cpu's parallelization queue, - * so exit imediately. + * so exit immediately. */ if (PTR_ERR(padata) == -ENODATA) { del_timer(&pd->timer); @@ -284,7 +284,7 @@ static void padata_reorder(struct parallel_data *pd) /* * The next object that needs serialization might have arrived to * the reorder queues in the meantime, we will be called again - * from the timer function if noone else cares for it. + * from the timer function if no one else cares for it. */ if (atomic_read(&pd->reorder_objects) && !(pinst->flags & PADATA_RESET)) @@ -515,7 +515,7 @@ static void __padata_stop(struct padata_instance *pinst) put_online_cpus(); } -/* Replace the internal control stucture with a new one. */ +/* Replace the internal control structure with a new one. */ static void padata_replace(struct padata_instance *pinst, struct parallel_data *pd_new) { @@ -768,7 +768,7 @@ static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) } /** - * padata_remove_cpu - remove a cpu from the one or both(serial and paralell) + * padata_remove_cpu - remove a cpu from the one or both(serial and parallel) * padata cpumasks. * * @pinst: padata instance diff --git a/kernel/panic.c b/kernel/panic.c index 4c13b1a88eb..69231670eb9 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -34,6 +34,7 @@ static int pause_on_oops_flag; static DEFINE_SPINLOCK(pause_on_oops_lock); int panic_timeout; +EXPORT_SYMBOL_GPL(panic_timeout); ATOMIC_NOTIFIER_HEAD(panic_notifier_list); @@ -432,3 +433,13 @@ EXPORT_SYMBOL(__stack_chk_fail); core_param(panic, panic_timeout, int, 0644); core_param(pause_on_oops, pause_on_oops, int, 0644); + +static int __init oops_setup(char *s) +{ + if (!s) + return -EINVAL; + if (!strcmp(s, "panic")) + panic_on_oops = 1; + return 0; +} +early_param("oops", oops_setup); diff --git a/kernel/params.c b/kernel/params.c index 08107d18175..ed72e133086 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -95,7 +95,7 @@ static int parse_one(char *param, /* Find parameter */ for (i = 0; i < num_params; i++) { if (parameq(param, params[i].name)) { - /* Noone handled NULL, so do it here. */ + /* No one handled NULL, so do it here. */ if (!val && params[i].ops->set != param_set_bool) return -EINVAL; DEBUGP("They are equal! Calling %p\n", @@ -297,21 +297,15 @@ EXPORT_SYMBOL(param_ops_charp); int param_set_bool(const char *val, const struct kernel_param *kp) { bool v; + int ret; /* No equals means "set"... */ if (!val) val = "1"; /* One of =[yYnN01] */ - switch (val[0]) { - case 'y': case 'Y': case '1': - v = true; - break; - case 'n': case 'N': case '0': - v = false; - break; - default: - return -EINVAL; - } + ret = strtobool(val, &v); + if (ret) + return ret; if (kp->flags & KPARAM_ISBOOL) *(bool *)kp->arg = v; @@ -719,9 +713,7 @@ void destroy_params(const struct kernel_param *params, unsigned num) params[i].ops->free(params[i].arg); } -static void __init kernel_add_sysfs_param(const char *name, - struct kernel_param *kparam, - unsigned int name_skip) +static struct module_kobject * __init locate_module_kobject(const char *name) { struct module_kobject *mk; struct kobject *kobj; @@ -729,10 +721,7 @@ static void __init kernel_add_sysfs_param(const char *name, kobj = kset_find_obj(module_kset, name); if (kobj) { - /* We already have one. Remove params so we can add more. */ mk = to_module_kobject(kobj); - /* We need to remove it before adding parameters. */ - sysfs_remove_group(&mk->kobj, &mk->mp->grp); } else { mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL); BUG_ON(!mk); @@ -743,15 +732,36 @@ static void __init kernel_add_sysfs_param(const char *name, "%s", name); if (err) { kobject_put(&mk->kobj); - printk(KERN_ERR "Module '%s' failed add to sysfs, " - "error number %d\n", name, err); - printk(KERN_ERR "The system will be unstable now.\n"); - return; + printk(KERN_ERR + "Module '%s' failed add to sysfs, error number %d\n", + name, err); + printk(KERN_ERR + "The system will be unstable now.\n"); + return NULL; } - /* So that exit path is even. */ + + /* So that we hold reference in both cases. */ kobject_get(&mk->kobj); } + return mk; +} + +static void __init kernel_add_sysfs_param(const char *name, + struct kernel_param *kparam, + unsigned int name_skip) +{ + struct module_kobject *mk; + int err; + + mk = locate_module_kobject(name); + if (!mk) + return; + + /* We need to remove old parameters before adding more. */ + if (mk->mp) + sysfs_remove_group(&mk->kobj, &mk->mp->grp); + /* These should not fail at boot. */ err = add_sysfs_param(mk, kparam, kparam->name + name_skip); BUG_ON(err); @@ -796,6 +806,35 @@ static void __init param_sysfs_builtin(void) } } +ssize_t __modver_version_show(struct module_attribute *mattr, + struct module *mod, char *buf) +{ + struct module_version_attribute *vattr = + container_of(mattr, struct module_version_attribute, mattr); + + return sprintf(buf, "%s\n", vattr->version); +} + +extern const struct module_version_attribute *__start___modver[]; +extern const struct module_version_attribute *__stop___modver[]; + +static void __init version_sysfs_builtin(void) +{ + const struct module_version_attribute **p; + struct module_kobject *mk; + int err; + + for (p = __start___modver; p < __stop___modver; p++) { + const struct module_version_attribute *vattr = *p; + + mk = locate_module_kobject(vattr->module_name); + if (mk) { + err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr); + kobject_uevent(&mk->kobj, KOBJ_ADD); + kobject_put(&mk->kobj); + } + } +} /* module-related sysfs stuff */ @@ -875,6 +914,7 @@ static int __init param_sysfs_init(void) } module_sysfs_initialized = 1; + version_sysfs_builtin(); param_sysfs_builtin(); return 0; diff --git a/kernel/pid.c b/kernel/pid.c index 39b65b69584..57a8346a270 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -217,11 +217,14 @@ static int alloc_pidmap(struct pid_namespace *pid_ns) return -1; } -int next_pidmap(struct pid_namespace *pid_ns, int last) +int next_pidmap(struct pid_namespace *pid_ns, unsigned int last) { int offset; struct pidmap *map, *end; + if (last >= PID_MAX_LIMIT) + return -1; + offset = (last + 1) & BITS_PER_PAGE_MASK; map = &pid_ns->pidmap[(last + 1)/BITS_PER_PAGE]; end = &pid_ns->pidmap[PIDMAP_ENTRIES]; @@ -435,6 +438,7 @@ struct pid *get_task_pid(struct task_struct *task, enum pid_type type) rcu_read_unlock(); return pid; } +EXPORT_SYMBOL_GPL(get_task_pid); struct task_struct *get_pid_task(struct pid *pid, enum pid_type type) { @@ -446,6 +450,7 @@ struct task_struct *get_pid_task(struct pid *pid, enum pid_type type) rcu_read_unlock(); return result; } +EXPORT_SYMBOL_GPL(get_pid_task); struct pid *find_get_pid(pid_t nr) { diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index a5aff94e1f0..e9c9adc84ca 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -14,6 +14,7 @@ #include <linux/err.h> #include <linux/acct.h> #include <linux/slab.h> +#include <linux/proc_fs.h> #define BITS_PER_PAGE (PAGE_SIZE*8) @@ -72,7 +73,7 @@ static struct pid_namespace *create_pid_namespace(struct pid_namespace *parent_p { struct pid_namespace *ns; unsigned int level = parent_pid_ns->level + 1; - int i; + int i, err = -ENOMEM; ns = kmem_cache_zalloc(pid_ns_cachep, GFP_KERNEL); if (ns == NULL) @@ -96,14 +97,20 @@ static struct pid_namespace *create_pid_namespace(struct pid_namespace *parent_p for (i = 1; i < PIDMAP_ENTRIES; i++) atomic_set(&ns->pidmap[i].nr_free, BITS_PER_PAGE); + err = pid_ns_prepare_proc(ns); + if (err) + goto out_put_parent_pid_ns; + return ns; +out_put_parent_pid_ns: + put_pid_ns(parent_pid_ns); out_free_map: kfree(ns->pidmap[0].page); out_free: kmem_cache_free(pid_ns_cachep, ns); out: - return ERR_PTR(-ENOMEM); + return ERR_PTR(err); } static void destroy_pid_namespace(struct pid_namespace *ns) diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c index c7a8f453919..0da058bff8e 100644 --- a/kernel/pm_qos_params.c +++ b/kernel/pm_qos_params.c @@ -103,11 +103,14 @@ static struct pm_qos_object *pm_qos_array[] = { static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos); +static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos); static int pm_qos_power_open(struct inode *inode, struct file *filp); static int pm_qos_power_release(struct inode *inode, struct file *filp); static const struct file_operations pm_qos_power_fops = { .write = pm_qos_power_write, + .read = pm_qos_power_read, .open = pm_qos_power_open, .release = pm_qos_power_release, .llseek = noop_llseek, @@ -121,10 +124,10 @@ static inline int pm_qos_get_value(struct pm_qos_object *o) switch (o->type) { case PM_QOS_MIN: - return plist_last(&o->requests)->prio; + return plist_first(&o->requests)->prio; case PM_QOS_MAX: - return plist_first(&o->requests)->prio; + return plist_last(&o->requests)->prio; default: /* runtime check for not using enum */ @@ -376,6 +379,27 @@ static int pm_qos_power_release(struct inode *inode, struct file *filp) } +static ssize_t pm_qos_power_read(struct file *filp, char __user *buf, + size_t count, loff_t *f_pos) +{ + s32 value; + unsigned long flags; + struct pm_qos_object *o; + struct pm_qos_request_list *pm_qos_req = filp->private_data;; + + if (!pm_qos_req) + return -EINVAL; + if (!pm_qos_request_active(pm_qos_req)) + return -EINVAL; + + o = pm_qos_array[pm_qos_req->pm_qos_class]; + spin_lock_irqsave(&pm_qos_lock, flags); + value = pm_qos_get_value(o); + spin_unlock_irqrestore(&pm_qos_lock, flags); + + return simple_read_from_buffer(buf, count, f_pos, &value, sizeof(s32)); +} + static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, size_t count, loff_t *f_pos) { diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 6842eeba587..0791b13df7b 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -37,13 +37,13 @@ static int check_clock(const clockid_t which_clock) if (pid == 0) return 0; - read_lock(&tasklist_lock); + rcu_read_lock(); p = find_task_by_vpid(pid); if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ? - same_thread_group(p, current) : thread_group_leader(p))) { + same_thread_group(p, current) : has_group_leader_pid(p))) { error = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_unlock(); return error; } @@ -176,7 +176,8 @@ static inline cputime_t virt_ticks(struct task_struct *p) return p->utime; } -int posix_cpu_clock_getres(const clockid_t which_clock, struct timespec *tp) +static int +posix_cpu_clock_getres(const clockid_t which_clock, struct timespec *tp) { int error = check_clock(which_clock); if (!error) { @@ -194,7 +195,8 @@ int posix_cpu_clock_getres(const clockid_t which_clock, struct timespec *tp) return error; } -int posix_cpu_clock_set(const clockid_t which_clock, const struct timespec *tp) +static int +posix_cpu_clock_set(const clockid_t which_clock, const struct timespec *tp) { /* * You can never reset a CPU clock, but we check for other errors @@ -317,7 +319,7 @@ static int cpu_clock_sample_group(const clockid_t which_clock, } -int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) +static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) { const pid_t pid = CPUCLOCK_PID(which_clock); int error = -EINVAL; @@ -379,7 +381,7 @@ int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) * This is called from sys_timer_create() and do_cpu_nanosleep() with the * new timer already all-zeros initialized. */ -int posix_cpu_timer_create(struct k_itimer *new_timer) +static int posix_cpu_timer_create(struct k_itimer *new_timer) { int ret = 0; const pid_t pid = CPUCLOCK_PID(new_timer->it_clock); @@ -390,7 +392,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) INIT_LIST_HEAD(&new_timer->it.cpu.entry); - read_lock(&tasklist_lock); + rcu_read_lock(); if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) { if (pid == 0) { p = current; @@ -404,7 +406,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) p = current->group_leader; } else { p = find_task_by_vpid(pid); - if (p && !thread_group_leader(p)) + if (p && !has_group_leader_pid(p)) p = NULL; } } @@ -414,7 +416,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) } else { ret = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_unlock(); return ret; } @@ -425,7 +427,7 @@ int posix_cpu_timer_create(struct k_itimer *new_timer) * If we return TIMER_RETRY, it's necessary to release the timer's lock * and try again. (This happens when the timer is in the middle of firing.) */ -int posix_cpu_timer_del(struct k_itimer *timer) +static int posix_cpu_timer_del(struct k_itimer *timer) { struct task_struct *p = timer->it.cpu.task; int ret = 0; @@ -665,8 +667,8 @@ static int cpu_timer_sample_group(const clockid_t which_clock, * If we return TIMER_RETRY, it's necessary to release the timer's lock * and try again. (This happens when the timer is in the middle of firing.) */ -int posix_cpu_timer_set(struct k_itimer *timer, int flags, - struct itimerspec *new, struct itimerspec *old) +static int posix_cpu_timer_set(struct k_itimer *timer, int flags, + struct itimerspec *new, struct itimerspec *old) { struct task_struct *p = timer->it.cpu.task; union cpu_time_count old_expires, new_expires, old_incr, val; @@ -820,7 +822,7 @@ int posix_cpu_timer_set(struct k_itimer *timer, int flags, return ret; } -void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) +static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) { union cpu_time_count now; struct task_struct *p = timer->it.cpu.task; @@ -1345,7 +1347,7 @@ void run_posix_cpu_timers(struct task_struct *tsk) /* * Now that all the timers on our list have the firing flag, - * noone will touch their list entries but us. We'll take + * no one will touch their list entries but us. We'll take * each timer's lock before clearing its firing flag, so no * timer call will interfere. */ @@ -1481,11 +1483,13 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags, return error; } -int posix_cpu_nsleep(const clockid_t which_clock, int flags, - struct timespec *rqtp, struct timespec __user *rmtp) +static long posix_cpu_nsleep_restart(struct restart_block *restart_block); + +static int posix_cpu_nsleep(const clockid_t which_clock, int flags, + struct timespec *rqtp, struct timespec __user *rmtp) { struct restart_block *restart_block = - ¤t_thread_info()->restart_block; + ¤t_thread_info()->restart_block; struct itimerspec it; int error; @@ -1501,56 +1505,47 @@ int posix_cpu_nsleep(const clockid_t which_clock, int flags, if (error == -ERESTART_RESTARTBLOCK) { - if (flags & TIMER_ABSTIME) + if (flags & TIMER_ABSTIME) return -ERESTARTNOHAND; /* - * Report back to the user the time still remaining. - */ - if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) + * Report back to the user the time still remaining. + */ + if (rmtp && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) return -EFAULT; restart_block->fn = posix_cpu_nsleep_restart; - restart_block->arg0 = which_clock; - restart_block->arg1 = (unsigned long) rmtp; - restart_block->arg2 = rqtp->tv_sec; - restart_block->arg3 = rqtp->tv_nsec; + restart_block->nanosleep.index = which_clock; + restart_block->nanosleep.rmtp = rmtp; + restart_block->nanosleep.expires = timespec_to_ns(rqtp); } return error; } -long posix_cpu_nsleep_restart(struct restart_block *restart_block) +static long posix_cpu_nsleep_restart(struct restart_block *restart_block) { - clockid_t which_clock = restart_block->arg0; - struct timespec __user *rmtp; + clockid_t which_clock = restart_block->nanosleep.index; struct timespec t; struct itimerspec it; int error; - rmtp = (struct timespec __user *) restart_block->arg1; - t.tv_sec = restart_block->arg2; - t.tv_nsec = restart_block->arg3; + t = ns_to_timespec(restart_block->nanosleep.expires); - restart_block->fn = do_no_restart_syscall; error = do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t, &it); if (error == -ERESTART_RESTARTBLOCK) { + struct timespec __user *rmtp = restart_block->nanosleep.rmtp; /* - * Report back to the user the time still remaining. - */ - if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) + * Report back to the user the time still remaining. + */ + if (rmtp && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) return -EFAULT; - restart_block->fn = posix_cpu_nsleep_restart; - restart_block->arg0 = which_clock; - restart_block->arg1 = (unsigned long) rmtp; - restart_block->arg2 = t.tv_sec; - restart_block->arg3 = t.tv_nsec; + restart_block->nanosleep.expires = timespec_to_ns(&t); } return error; } - #define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED) #define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED) @@ -1594,38 +1589,37 @@ static int thread_cpu_timer_create(struct k_itimer *timer) timer->it_clock = THREAD_CLOCK; return posix_cpu_timer_create(timer); } -static int thread_cpu_nsleep(const clockid_t which_clock, int flags, - struct timespec *rqtp, struct timespec __user *rmtp) -{ - return -EINVAL; -} -static long thread_cpu_nsleep_restart(struct restart_block *restart_block) -{ - return -EINVAL; -} + +struct k_clock clock_posix_cpu = { + .clock_getres = posix_cpu_clock_getres, + .clock_set = posix_cpu_clock_set, + .clock_get = posix_cpu_clock_get, + .timer_create = posix_cpu_timer_create, + .nsleep = posix_cpu_nsleep, + .nsleep_restart = posix_cpu_nsleep_restart, + .timer_set = posix_cpu_timer_set, + .timer_del = posix_cpu_timer_del, + .timer_get = posix_cpu_timer_get, +}; static __init int init_posix_cpu_timers(void) { struct k_clock process = { - .clock_getres = process_cpu_clock_getres, - .clock_get = process_cpu_clock_get, - .clock_set = do_posix_clock_nosettime, - .timer_create = process_cpu_timer_create, - .nsleep = process_cpu_nsleep, - .nsleep_restart = process_cpu_nsleep_restart, + .clock_getres = process_cpu_clock_getres, + .clock_get = process_cpu_clock_get, + .timer_create = process_cpu_timer_create, + .nsleep = process_cpu_nsleep, + .nsleep_restart = process_cpu_nsleep_restart, }; struct k_clock thread = { - .clock_getres = thread_cpu_clock_getres, - .clock_get = thread_cpu_clock_get, - .clock_set = do_posix_clock_nosettime, - .timer_create = thread_cpu_timer_create, - .nsleep = thread_cpu_nsleep, - .nsleep_restart = thread_cpu_nsleep_restart, + .clock_getres = thread_cpu_clock_getres, + .clock_get = thread_cpu_clock_get, + .timer_create = thread_cpu_timer_create, }; struct timespec ts; - register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); - register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); + posix_timers_register_clock(CLOCK_PROCESS_CPUTIME_ID, &process); + posix_timers_register_clock(CLOCK_THREAD_CPUTIME_ID, &thread); cputime_to_timespec(cputime_one_jiffy, &ts); onecputick = ts.tv_nsec; diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index 9ca4973f736..e5498d7405c 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -41,6 +41,7 @@ #include <linux/init.h> #include <linux/compiler.h> #include <linux/idr.h> +#include <linux/posix-clock.h> #include <linux/posix-timers.h> #include <linux/syscalls.h> #include <linux/wait.h> @@ -81,6 +82,14 @@ static DEFINE_SPINLOCK(idr_lock); #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!" #endif +/* + * parisc wants ENOTSUP instead of EOPNOTSUPP + */ +#ifndef ENOTSUP +# define ENANOSLEEP_NOTSUP EOPNOTSUPP +#else +# define ENANOSLEEP_NOTSUP ENOTSUP +#endif /* * The timer ID is turned into a timer address by idr_find(). @@ -94,11 +103,7 @@ static DEFINE_SPINLOCK(idr_lock); /* * CLOCKs: The POSIX standard calls for a couple of clocks and allows us * to implement others. This structure defines the various - * clocks and allows the possibility of adding others. We - * provide an interface to add clocks to the table and expect - * the "arch" code to add at least one clock that is high - * resolution. Here we define the standard CLOCK_REALTIME as a - * 1/HZ resolution clock. + * clocks. * * RESOLUTION: Clock resolution is used to round up timer and interval * times, NOT to report clock times, which are reported with as @@ -108,20 +113,13 @@ static DEFINE_SPINLOCK(idr_lock); * necessary code is written. The standard says we should say * something about this issue in the documentation... * - * FUNCTIONS: The CLOCKs structure defines possible functions to handle - * various clock functions. For clocks that use the standard - * system timer code these entries should be NULL. This will - * allow dispatch without the overhead of indirect function - * calls. CLOCKS that depend on other sources (e.g. WWV or GPS) - * must supply functions here, even if the function just returns - * ENOSYS. The standard POSIX timer management code assumes the - * following: 1.) The k_itimer struct (sched.h) is used for the - * timer. 2.) The list, it_lock, it_clock, it_id and it_pid - * fields are not modified by timer code. + * FUNCTIONS: The CLOCKs structure defines possible functions to + * handle various clock functions. * - * At this time all functions EXCEPT clock_nanosleep can be - * redirected by the CLOCKS structure. Clock_nanosleep is in - * there, but the code ignores it. + * The standard POSIX timer management code assumes the + * following: 1.) The k_itimer struct (sched.h) is used for + * the timer. 2.) The list, it_lock, it_clock, it_id and + * it_pid fields are not modified by timer code. * * Permissions: It is assumed that the clock_settime() function defined * for each clock will take care of permission checks. Some @@ -138,6 +136,7 @@ static struct k_clock posix_clocks[MAX_CLOCKS]; */ static int common_nsleep(const clockid_t, int flags, struct timespec *t, struct timespec __user *rmtp); +static int common_timer_create(struct k_itimer *new_timer); static void common_timer_get(struct k_itimer *, struct itimerspec *); static int common_timer_set(struct k_itimer *, int, struct itimerspec *, struct itimerspec *); @@ -145,83 +144,37 @@ static int common_timer_del(struct k_itimer *timer); static enum hrtimer_restart posix_timer_fn(struct hrtimer *data); -static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags); +static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags); + +#define lock_timer(tid, flags) \ +({ struct k_itimer *__timr; \ + __cond_lock(&__timr->it_lock, __timr = __lock_timer(tid, flags)); \ + __timr; \ +}) static inline void unlock_timer(struct k_itimer *timr, unsigned long flags) { spin_unlock_irqrestore(&timr->it_lock, flags); } -/* - * Call the k_clock hook function if non-null, or the default function. - */ -#define CLOCK_DISPATCH(clock, call, arglist) \ - ((clock) < 0 ? posix_cpu_##call arglist : \ - (posix_clocks[clock].call != NULL \ - ? (*posix_clocks[clock].call) arglist : common_##call arglist)) - -/* - * Default clock hook functions when the struct k_clock passed - * to register_posix_clock leaves a function pointer null. - * - * The function common_CALL is the default implementation for - * the function pointer CALL in struct k_clock. - */ - -static inline int common_clock_getres(const clockid_t which_clock, - struct timespec *tp) -{ - tp->tv_sec = 0; - tp->tv_nsec = posix_clocks[which_clock].res; - return 0; -} - -/* - * Get real time for posix timers - */ -static int common_clock_get(clockid_t which_clock, struct timespec *tp) +/* Get clock_realtime */ +static int posix_clock_realtime_get(clockid_t which_clock, struct timespec *tp) { ktime_get_real_ts(tp); return 0; } -static inline int common_clock_set(const clockid_t which_clock, - struct timespec *tp) +/* Set clock_realtime */ +static int posix_clock_realtime_set(const clockid_t which_clock, + const struct timespec *tp) { return do_sys_settimeofday(tp, NULL); } -static int common_timer_create(struct k_itimer *new_timer) -{ - hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0); - return 0; -} - -static int no_timer_create(struct k_itimer *new_timer) +static int posix_clock_realtime_adj(const clockid_t which_clock, + struct timex *t) { - return -EOPNOTSUPP; -} - -static int no_nsleep(const clockid_t which_clock, int flags, - struct timespec *tsave, struct timespec __user *rmtp) -{ - return -EOPNOTSUPP; -} - -/* - * Return nonzero if we know a priori this clockid_t value is bogus. - */ -static inline int invalid_clockid(const clockid_t which_clock) -{ - if (which_clock < 0) /* CPU clock, posix_cpu_* will check it */ - return 0; - if ((unsigned) which_clock >= MAX_CLOCKS) - return 1; - if (posix_clocks[which_clock].clock_getres != NULL) - return 0; - if (posix_clocks[which_clock].res != 0) - return 0; - return 1; + return do_adjtimex(t); } /* @@ -234,7 +187,7 @@ static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp) } /* - * Get monotonic time for posix timers + * Get monotonic-raw time for posix timers */ static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp) { @@ -261,46 +214,70 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp *tp = ktime_to_timespec(KTIME_LOW_RES); return 0; } + +static int posix_get_boottime(const clockid_t which_clock, struct timespec *tp) +{ + get_monotonic_boottime(tp); + return 0; +} + + /* * Initialize everything, well, just everything in Posix clocks/timers ;) */ static __init int init_posix_timers(void) { struct k_clock clock_realtime = { - .clock_getres = hrtimer_get_res, + .clock_getres = hrtimer_get_res, + .clock_get = posix_clock_realtime_get, + .clock_set = posix_clock_realtime_set, + .clock_adj = posix_clock_realtime_adj, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, }; struct k_clock clock_monotonic = { - .clock_getres = hrtimer_get_res, - .clock_get = posix_ktime_get_ts, - .clock_set = do_posix_clock_nosettime, + .clock_getres = hrtimer_get_res, + .clock_get = posix_ktime_get_ts, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, }; struct k_clock clock_monotonic_raw = { - .clock_getres = hrtimer_get_res, - .clock_get = posix_get_monotonic_raw, - .clock_set = do_posix_clock_nosettime, - .timer_create = no_timer_create, - .nsleep = no_nsleep, + .clock_getres = hrtimer_get_res, + .clock_get = posix_get_monotonic_raw, }; struct k_clock clock_realtime_coarse = { - .clock_getres = posix_get_coarse_res, - .clock_get = posix_get_realtime_coarse, - .clock_set = do_posix_clock_nosettime, - .timer_create = no_timer_create, - .nsleep = no_nsleep, + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_realtime_coarse, }; struct k_clock clock_monotonic_coarse = { - .clock_getres = posix_get_coarse_res, - .clock_get = posix_get_monotonic_coarse, - .clock_set = do_posix_clock_nosettime, - .timer_create = no_timer_create, - .nsleep = no_nsleep, + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_monotonic_coarse, + }; + struct k_clock clock_boottime = { + .clock_getres = hrtimer_get_res, + .clock_get = posix_get_boottime, + .nsleep = common_nsleep, + .nsleep_restart = hrtimer_nanosleep_restart, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, }; - register_posix_clock(CLOCK_REALTIME, &clock_realtime); - register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic); - register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw); - register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse); - register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse); + posix_timers_register_clock(CLOCK_REALTIME, &clock_realtime); + posix_timers_register_clock(CLOCK_MONOTONIC, &clock_monotonic); + posix_timers_register_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw); + posix_timers_register_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse); + posix_timers_register_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse); + posix_timers_register_clock(CLOCK_BOOTTIME, &clock_boottime); posix_timers_cache = kmem_cache_create("posix_timers_cache", sizeof (struct k_itimer), 0, SLAB_PANIC, @@ -336,7 +313,7 @@ static void schedule_next_timer(struct k_itimer *timr) * restarted (i.e. we have flagged this in the sys_private entry of the * info block). * - * To protect aginst the timer going away while the interrupt is queued, + * To protect against the timer going away while the interrupt is queued, * we require that the it_requeue_pending flag be set. */ void do_schedule_next_timer(struct siginfo *info) @@ -476,17 +453,29 @@ static struct pid *good_sigevent(sigevent_t * event) return task_pid(rtn); } -void register_posix_clock(const clockid_t clock_id, struct k_clock *new_clock) +void posix_timers_register_clock(const clockid_t clock_id, + struct k_clock *new_clock) { if ((unsigned) clock_id >= MAX_CLOCKS) { - printk("POSIX clock register failed for clock_id %d\n", + printk(KERN_WARNING "POSIX clock register failed for clock_id %d\n", + clock_id); + return; + } + + if (!new_clock->clock_get) { + printk(KERN_WARNING "POSIX clock id %d lacks clock_get()\n", + clock_id); + return; + } + if (!new_clock->clock_getres) { + printk(KERN_WARNING "POSIX clock id %d lacks clock_getres()\n", clock_id); return; } posix_clocks[clock_id] = *new_clock; } -EXPORT_SYMBOL_GPL(register_posix_clock); +EXPORT_SYMBOL_GPL(posix_timers_register_clock); static struct k_itimer * alloc_posix_timer(void) { @@ -517,19 +506,39 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set) kmem_cache_free(posix_timers_cache, tmr); } +static struct k_clock *clockid_to_kclock(const clockid_t id) +{ + if (id < 0) + return (id & CLOCKFD_MASK) == CLOCKFD ? + &clock_posix_dynamic : &clock_posix_cpu; + + if (id >= MAX_CLOCKS || !posix_clocks[id].clock_getres) + return NULL; + return &posix_clocks[id]; +} + +static int common_timer_create(struct k_itimer *new_timer) +{ + hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0); + return 0; +} + /* Create a POSIX.1b interval timer. */ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock, struct sigevent __user *, timer_event_spec, timer_t __user *, created_timer_id) { + struct k_clock *kc = clockid_to_kclock(which_clock); struct k_itimer *new_timer; int error, new_timer_id; sigevent_t event; int it_id_set = IT_ID_NOT_SET; - if (invalid_clockid(which_clock)) + if (!kc) return -EINVAL; + if (!kc->timer_create) + return -EOPNOTSUPP; new_timer = alloc_posix_timer(); if (unlikely(!new_timer)) @@ -591,7 +600,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock, goto out; } - error = CLOCK_DISPATCH(which_clock, timer_create, (new_timer)); + error = kc->timer_create(new_timer); if (error) goto out; @@ -601,7 +610,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock, spin_unlock_irq(¤t->sighand->siglock); return 0; - /* + /* * In the case of the timer belonging to another task, after * the task is unlocked, the timer is owned by the other task * and may cease to exist at any time. Don't use or modify @@ -619,7 +628,7 @@ out: * the find to the timer lock. To avoid a dead lock, the timer id MUST * be release with out holding the timer lock. */ -static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags) +static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags) { struct k_itimer *timr; /* @@ -703,22 +712,28 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id, struct itimerspec __user *, setting) { - struct k_itimer *timr; struct itimerspec cur_setting; + struct k_itimer *timr; + struct k_clock *kc; unsigned long flags; + int ret = 0; timr = lock_timer(timer_id, &flags); if (!timr) return -EINVAL; - CLOCK_DISPATCH(timr->it_clock, timer_get, (timr, &cur_setting)); + kc = clockid_to_kclock(timr->it_clock); + if (WARN_ON_ONCE(!kc || !kc->timer_get)) + ret = -EINVAL; + else + kc->timer_get(timr, &cur_setting); unlock_timer(timr, flags); - if (copy_to_user(setting, &cur_setting, sizeof (cur_setting))) + if (!ret && copy_to_user(setting, &cur_setting, sizeof (cur_setting))) return -EFAULT; - return 0; + return ret; } /* @@ -807,6 +822,7 @@ SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags, int error = 0; unsigned long flag; struct itimerspec *rtn = old_setting ? &old_spec : NULL; + struct k_clock *kc; if (!new_setting) return -EINVAL; @@ -822,8 +838,11 @@ retry: if (!timr) return -EINVAL; - error = CLOCK_DISPATCH(timr->it_clock, timer_set, - (timr, flags, &new_spec, rtn)); + kc = clockid_to_kclock(timr->it_clock); + if (WARN_ON_ONCE(!kc || !kc->timer_set)) + error = -EINVAL; + else + error = kc->timer_set(timr, flags, &new_spec, rtn); unlock_timer(timr, flag); if (error == TIMER_RETRY) { @@ -838,7 +857,7 @@ retry: return error; } -static inline int common_timer_del(struct k_itimer *timer) +static int common_timer_del(struct k_itimer *timer) { timer->it.real.interval.tv64 = 0; @@ -849,7 +868,11 @@ static inline int common_timer_del(struct k_itimer *timer) static inline int timer_delete_hook(struct k_itimer *timer) { - return CLOCK_DISPATCH(timer->it_clock, timer_del, (timer)); + struct k_clock *kc = clockid_to_kclock(timer->it_clock); + + if (WARN_ON_ONCE(!kc || !kc->timer_del)) + return -EINVAL; + return kc->timer_del(timer); } /* Delete a POSIX.1b interval timer. */ @@ -921,69 +944,76 @@ void exit_itimers(struct signal_struct *sig) } } -/* Not available / possible... functions */ -int do_posix_clock_nosettime(const clockid_t clockid, struct timespec *tp) -{ - return -EINVAL; -} -EXPORT_SYMBOL_GPL(do_posix_clock_nosettime); - -int do_posix_clock_nonanosleep(const clockid_t clock, int flags, - struct timespec *t, struct timespec __user *r) -{ -#ifndef ENOTSUP - return -EOPNOTSUPP; /* aka ENOTSUP in userland for POSIX */ -#else /* parisc does define it separately. */ - return -ENOTSUP; -#endif -} -EXPORT_SYMBOL_GPL(do_posix_clock_nonanosleep); - SYSCALL_DEFINE2(clock_settime, const clockid_t, which_clock, const struct timespec __user *, tp) { + struct k_clock *kc = clockid_to_kclock(which_clock); struct timespec new_tp; - if (invalid_clockid(which_clock)) + if (!kc || !kc->clock_set) return -EINVAL; + if (copy_from_user(&new_tp, tp, sizeof (*tp))) return -EFAULT; - return CLOCK_DISPATCH(which_clock, clock_set, (which_clock, &new_tp)); + return kc->clock_set(which_clock, &new_tp); } SYSCALL_DEFINE2(clock_gettime, const clockid_t, which_clock, struct timespec __user *,tp) { + struct k_clock *kc = clockid_to_kclock(which_clock); struct timespec kernel_tp; int error; - if (invalid_clockid(which_clock)) + if (!kc) return -EINVAL; - error = CLOCK_DISPATCH(which_clock, clock_get, - (which_clock, &kernel_tp)); + + error = kc->clock_get(which_clock, &kernel_tp); + if (!error && copy_to_user(tp, &kernel_tp, sizeof (kernel_tp))) error = -EFAULT; return error; +} + +SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock, + struct timex __user *, utx) +{ + struct k_clock *kc = clockid_to_kclock(which_clock); + struct timex ktx; + int err; + + if (!kc) + return -EINVAL; + if (!kc->clock_adj) + return -EOPNOTSUPP; + + if (copy_from_user(&ktx, utx, sizeof(ktx))) + return -EFAULT; + + err = kc->clock_adj(which_clock, &ktx); + + if (!err && copy_to_user(utx, &ktx, sizeof(ktx))) + return -EFAULT; + return err; } SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock, struct timespec __user *, tp) { + struct k_clock *kc = clockid_to_kclock(which_clock); struct timespec rtn_tp; int error; - if (invalid_clockid(which_clock)) + if (!kc) return -EINVAL; - error = CLOCK_DISPATCH(which_clock, clock_getres, - (which_clock, &rtn_tp)); + error = kc->clock_getres(which_clock, &rtn_tp); - if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp))) { + if (!error && tp && copy_to_user(tp, &rtn_tp, sizeof (rtn_tp))) error = -EFAULT; - } return error; } @@ -1003,10 +1033,13 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, const struct timespec __user *, rqtp, struct timespec __user *, rmtp) { + struct k_clock *kc = clockid_to_kclock(which_clock); struct timespec t; - if (invalid_clockid(which_clock)) + if (!kc) return -EINVAL; + if (!kc->nsleep) + return -ENANOSLEEP_NOTSUP; if (copy_from_user(&t, rqtp, sizeof (struct timespec))) return -EFAULT; @@ -1014,27 +1047,20 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, if (!timespec_valid(&t)) return -EINVAL; - return CLOCK_DISPATCH(which_clock, nsleep, - (which_clock, flags, &t, rmtp)); -} - -/* - * nanosleep_restart for monotonic and realtime clocks - */ -static int common_nsleep_restart(struct restart_block *restart_block) -{ - return hrtimer_nanosleep_restart(restart_block); + return kc->nsleep(which_clock, flags, &t, rmtp); } /* * This will restart clock_nanosleep. This is required only by * compat_clock_nanosleep_restart for now. */ -long -clock_nanosleep_restart(struct restart_block *restart_block) +long clock_nanosleep_restart(struct restart_block *restart_block) { - clockid_t which_clock = restart_block->arg0; + clockid_t which_clock = restart_block->nanosleep.index; + struct k_clock *kc = clockid_to_kclock(which_clock); + + if (WARN_ON_ONCE(!kc || !kc->nsleep_restart)) + return -EINVAL; - return CLOCK_DISPATCH(which_clock, nsleep_restart, - (restart_block)); + return kc->nsleep_restart(restart_block); } diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 29bff6117ab..87f4d24b55b 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -1,129 +1,12 @@ -config PM - bool "Power Management support" - depends on !IA64_HP_SIM - ---help--- - "Power Management" means that parts of your computer are shut - off or put into a power conserving "sleep" mode if they are not - being used. There are two competing standards for doing this: APM - and ACPI. If you want to use either one, say Y here and then also - to the requisite support below. - - Power Management is most important for battery powered laptop - computers; if you have a laptop, check out the Linux Laptop home - page on the WWW at <http://www.linux-on-laptops.com/> or - Tuxmobil - Linux on Mobile Computers at <http://www.tuxmobil.org/> - and the Battery Powered Linux mini-HOWTO, available from - <http://www.tldp.org/docs.html#howto>. - - Note that, even if you say N here, Linux on the x86 architecture - will issue the hlt instruction if nothing is to be done, thereby - sending the processor to sleep and saving power. - -config PM_DEBUG - bool "Power Management Debug Support" - depends on PM - ---help--- - This option enables various debugging support in the Power Management - code. This is helpful when debugging and reporting PM bugs, like - suspend support. - -config PM_ADVANCED_DEBUG - bool "Extra PM attributes in sysfs for low-level debugging/testing" - depends on PM_DEBUG - default n - ---help--- - Add extra sysfs attributes allowing one to access some Power Management - fields of device objects from user space. If you are not a kernel - developer interested in debugging/testing Power Management, say "no". - -config PM_VERBOSE - bool "Verbose Power Management debugging" - depends on PM_DEBUG - default n - ---help--- - This option enables verbose messages from the Power Management code. - -config CAN_PM_TRACE - def_bool y - depends on PM_DEBUG && PM_SLEEP && EXPERIMENTAL - -config PM_TRACE - bool - help - This enables code to save the last PM event point across - reboot. The architecture needs to support this, x86 for - example does by saving things in the RTC, see below. - - The architecture specific code must provide the extern - functions from <linux/resume-trace.h> as well as the - <asm/resume-trace.h> header with a TRACE_RESUME() macro. - - The way the information is presented is architecture- - dependent, x86 will print the information during a - late_initcall. - -config PM_TRACE_RTC - bool "Suspend/resume event tracing" - depends on CAN_PM_TRACE - depends on X86 - select PM_TRACE - default n - ---help--- - This enables some cheesy code to save the last PM event point in the - RTC across reboots, so that you can debug a machine that just hangs - during suspend (or more commonly, during resume). - - To use this debugging feature you should attempt to suspend the - machine, reboot it and then run - - dmesg -s 1000000 | grep 'hash matches' - - CAUTION: this option will cause your machine's real-time clock to be - set to an invalid time after a resume. - -config PM_SLEEP_SMP - bool - depends on SMP - depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE - depends on PM_SLEEP - select HOTPLUG - select HOTPLUG_CPU - default y - -config PM_SLEEP - bool - depends on SUSPEND || HIBERNATION || XEN_SAVE_RESTORE - default y - -config PM_SLEEP_ADVANCED_DEBUG - bool - depends on PM_ADVANCED_DEBUG - default n - -config SUSPEND_NVS - bool - config SUSPEND bool "Suspend to RAM and standby" - depends on PM && ARCH_SUSPEND_POSSIBLE - select SUSPEND_NVS if HAS_IOMEM + depends on ARCH_SUSPEND_POSSIBLE default y ---help--- Allow the system to enter sleep states in which main memory is powered and thus its contents are preserved, such as the suspend-to-RAM state (e.g. the ACPI S3 state). -config PM_TEST_SUSPEND - bool "Test suspend/resume and wakealarm during bootup" - depends on SUSPEND && PM_DEBUG && RTC_CLASS=y - ---help--- - This option will let you suspend your machine during bootup, and - make it wake up a few seconds later using an RTC wakeup alarm. - Enable this with a kernel parameter like "test_suspend=mem". - - You probably want to have your system's RTC driver statically - linked, ensuring that it's available when this test runs. - config SUSPEND_FREEZER bool "Enable freezer for suspend to RAM/standby" \ if ARCH_WANTS_FREEZER_CONTROL || BROKEN @@ -135,12 +18,15 @@ config SUSPEND_FREEZER Turning OFF this setting is NOT recommended! If in doubt, say Y. +config HIBERNATE_CALLBACKS + bool + config HIBERNATION bool "Hibernation (aka 'suspend to disk')" - depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE + depends on SWAP && ARCH_HIBERNATION_POSSIBLE + select HIBERNATE_CALLBACKS select LZO_COMPRESS select LZO_DECOMPRESS - select SUSPEND_NVS if HAS_IOMEM ---help--- Enable the suspend to disk (STD) functionality, which is usually called "hibernation" in user interfaces. STD checkpoints the @@ -201,6 +87,100 @@ config PM_STD_PARTITION suspended image to. It will simply pick the first available swap device. +config PM_SLEEP + def_bool y + depends on SUSPEND || HIBERNATE_CALLBACKS + +config PM_SLEEP_SMP + def_bool y + depends on SMP + depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE + depends on PM_SLEEP + select HOTPLUG + select HOTPLUG_CPU + +config PM_RUNTIME + bool "Run-time PM core functionality" + depends on !IA64_HP_SIM + ---help--- + Enable functionality allowing I/O devices to be put into energy-saving + (low power) states at run time (or autosuspended) after a specified + period of inactivity and woken up in response to a hardware-generated + wake-up event or a driver's request. + + Hardware support is generally required for this functionality to work + and the bus type drivers of the buses the devices are on are + responsible for the actual handling of the autosuspend requests and + wake-up events. + +config PM + def_bool y + depends on PM_SLEEP || PM_RUNTIME + +config PM_DEBUG + bool "Power Management Debug Support" + depends on PM + ---help--- + This option enables various debugging support in the Power Management + code. This is helpful when debugging and reporting PM bugs, like + suspend support. + +config PM_ADVANCED_DEBUG + bool "Extra PM attributes in sysfs for low-level debugging/testing" + depends on PM_DEBUG + ---help--- + Add extra sysfs attributes allowing one to access some Power Management + fields of device objects from user space. If you are not a kernel + developer interested in debugging/testing Power Management, say "no". + +config PM_TEST_SUSPEND + bool "Test suspend/resume and wakealarm during bootup" + depends on SUSPEND && PM_DEBUG && RTC_CLASS=y + ---help--- + This option will let you suspend your machine during bootup, and + make it wake up a few seconds later using an RTC wakeup alarm. + Enable this with a kernel parameter like "test_suspend=mem". + + You probably want to have your system's RTC driver statically + linked, ensuring that it's available when this test runs. + +config CAN_PM_TRACE + def_bool y + depends on PM_DEBUG && PM_SLEEP + +config PM_TRACE + bool + help + This enables code to save the last PM event point across + reboot. The architecture needs to support this, x86 for + example does by saving things in the RTC, see below. + + The architecture specific code must provide the extern + functions from <linux/resume-trace.h> as well as the + <asm/resume-trace.h> header with a TRACE_RESUME() macro. + + The way the information is presented is architecture- + dependent, x86 will print the information during a + late_initcall. + +config PM_TRACE_RTC + bool "Suspend/resume event tracing" + depends on CAN_PM_TRACE + depends on X86 + select PM_TRACE + ---help--- + This enables some cheesy code to save the last PM event point in the + RTC across reboots, so that you can debug a machine that just hangs + during suspend (or more commonly, during resume). + + To use this debugging feature you should attempt to suspend the + machine, reboot it and then run + + dmesg -s 1000000 | grep 'hash matches' + + CAUTION: this option will cause your machine's real-time clock to be + set to an invalid time after a resume. + config APM_EMULATION tristate "Advanced Power Management Emulation" depends on PM && SYS_SUPPORTS_APM_EMULATION @@ -227,28 +207,12 @@ config APM_EMULATION anything, try disabling/enabling this option (or disabling/enabling APM in your BIOS). -config PM_RUNTIME - bool "Run-time PM core functionality" - depends on PM - ---help--- - Enable functionality allowing I/O devices to be put into energy-saving - (low power) states at run time (or autosuspended) after a specified - period of inactivity and woken up in response to a hardware-generated - wake-up event or a driver's request. - - Hardware support is generally required for this functionality to work - and the bus type drivers of the buses the devices are on are - responsible for the actual handling of the autosuspend requests and - wake-up events. - -config PM_OPS +config ARCH_HAS_OPP bool - depends on PM_SLEEP || PM_RUNTIME - default y config PM_OPP bool "Operating Performance Point (OPP) Layer library" - depends on PM + depends on ARCH_HAS_OPP ---help--- SOCs have a standard set of tuples consisting of frequency and voltage pairs that the device will support per voltage domain. This @@ -259,3 +223,7 @@ config PM_OPP representing individual voltage domains and provides SOC implementations a ready to use framework to manage OPPs. For more information, read <file:Documentation/power/opp.txt> + +config PM_RUNTIME_CLK + def_bool y + depends on PM_RUNTIME && HAVE_CLK diff --git a/kernel/power/Makefile b/kernel/power/Makefile index f9063c6b185..c5ebc6a9064 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -1,7 +1,5 @@ -ifeq ($(CONFIG_PM_DEBUG),y) -EXTRA_CFLAGS += -DDEBUG -endif +ccflags-$(CONFIG_PM_DEBUG) := -DDEBUG obj-$(CONFIG_PM) += main.o obj-$(CONFIG_PM_SLEEP) += console.o @@ -10,6 +8,5 @@ obj-$(CONFIG_SUSPEND) += suspend.o obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o obj-$(CONFIG_HIBERNATION) += hibernate.o snapshot.o swap.o user.o \ block_io.o -obj-$(CONFIG_SUSPEND_NVS) += nvs.o obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c index 83bbc7c02df..d09dd10c5a5 100644 --- a/kernel/power/block_io.c +++ b/kernel/power/block_io.c @@ -28,7 +28,7 @@ static int submit(int rw, struct block_device *bdev, sector_t sector, struct page *page, struct bio **bio_chain) { - const int bio_rw = rw | REQ_SYNC | REQ_UNPLUG; + const int bio_rw = rw | REQ_SYNC; struct bio *bio; bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 657272e91d0..f9bec56d882 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -23,6 +23,7 @@ #include <linux/cpu.h> #include <linux/freezer.h> #include <linux/gfp.h> +#include <linux/syscore_ops.h> #include <scsi/scsi_scan.h> #include <asm/suspend.h> @@ -51,18 +52,18 @@ enum { static int hibernation_mode = HIBERNATION_SHUTDOWN; -static struct platform_hibernation_ops *hibernation_ops; +static const struct platform_hibernation_ops *hibernation_ops; /** * hibernation_set_ops - set the global hibernate operations * @ops: the hibernation operations to use in subsequent hibernation transitions */ -void hibernation_set_ops(struct platform_hibernation_ops *ops) +void hibernation_set_ops(const struct platform_hibernation_ops *ops) { if (ops && !(ops->begin && ops->end && ops->pre_snapshot && ops->prepare && ops->finish && ops->enter && ops->pre_restore - && ops->restore_cleanup)) { + && ops->restore_cleanup && ops->leave)) { WARN_ON(1); return; } @@ -271,14 +272,14 @@ static int create_image(int platform_mode) local_irq_disable(); - error = sysdev_suspend(PMSG_FREEZE); + error = syscore_suspend(); if (error) { printk(KERN_ERR "PM: Some system devices failed to power down, " "aborting hibernation\n"); goto Enable_irqs; } - if (hibernation_test(TEST_CORE) || !pm_check_wakeup_events()) + if (hibernation_test(TEST_CORE) || pm_wakeup_pending()) goto Power_up; in_suspend = 1; @@ -295,7 +296,7 @@ static int create_image(int platform_mode) } Power_up: - sysdev_resume(); + syscore_resume(); /* NOTE: dpm_resume_noirq() is just a resume() for devices * that suspended with irqs off ... no overall powerup. */ @@ -326,21 +327,25 @@ static int create_image(int platform_mode) int hibernation_snapshot(int platform_mode) { + pm_message_t msg = PMSG_RECOVER; int error; - gfp_t saved_mask; error = platform_begin(platform_mode); if (error) goto Close; + error = dpm_prepare(PMSG_FREEZE); + if (error) + goto Complete_devices; + /* Preallocate image memory before shutting down devices. */ error = hibernate_preallocate_memory(); if (error) - goto Close; + goto Complete_devices; suspend_console(); - saved_mask = clear_gfp_allowed_mask(GFP_IOFS); - error = dpm_suspend_start(PMSG_FREEZE); + pm_restrict_gfp_mask(); + error = dpm_suspend(PMSG_FREEZE); if (error) goto Recover_platform; @@ -348,17 +353,27 @@ int hibernation_snapshot(int platform_mode) goto Recover_platform; error = create_image(platform_mode); - /* Control returns here after successful restore */ + /* + * Control returns here (1) after the image has been created or the + * image creation has failed and (2) after a successful restore. + */ Resume_devices: /* We may need to release the preallocated image pages here. */ if (error || !in_suspend) swsusp_free(); - dpm_resume_end(in_suspend ? - (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); - set_gfp_allowed_mask(saved_mask); + msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE; + dpm_resume(msg); + + if (error || !in_suspend) + pm_restore_gfp_mask(); + resume_console(); + + Complete_devices: + dpm_complete(msg); + Close: platform_end(platform_mode); return error; @@ -397,7 +412,7 @@ static int resume_target_kernel(bool platform_mode) local_irq_disable(); - error = sysdev_suspend(PMSG_QUIESCE); + error = syscore_suspend(); if (error) goto Enable_irqs; @@ -424,7 +439,7 @@ static int resume_target_kernel(bool platform_mode) restore_processor_state(); touch_softlockup_watchdog(); - sysdev_resume(); + syscore_resume(); Enable_irqs: local_irq_enable(); @@ -452,17 +467,16 @@ static int resume_target_kernel(bool platform_mode) int hibernation_restore(int platform_mode) { int error; - gfp_t saved_mask; pm_prepare_console(); suspend_console(); - saved_mask = clear_gfp_allowed_mask(GFP_IOFS); + pm_restrict_gfp_mask(); error = dpm_suspend_start(PMSG_QUIESCE); if (!error) { error = resume_target_kernel(platform_mode); dpm_resume_end(PMSG_RECOVER); } - set_gfp_allowed_mask(saved_mask); + pm_restore_gfp_mask(); resume_console(); pm_restore_console(); return error; @@ -476,7 +490,6 @@ int hibernation_restore(int platform_mode) int hibernation_platform_enter(void) { int error; - gfp_t saved_mask; if (!hibernation_ops) return -ENOSYS; @@ -492,7 +505,6 @@ int hibernation_platform_enter(void) entering_platform_hibernation = true; suspend_console(); - saved_mask = clear_gfp_allowed_mask(GFP_IOFS); error = dpm_suspend_start(PMSG_HIBERNATE); if (error) { if (hibernation_ops->recover) @@ -513,8 +525,8 @@ int hibernation_platform_enter(void) goto Platform_finish; local_irq_disable(); - sysdev_suspend(PMSG_HIBERNATE); - if (!pm_check_wakeup_events()) { + syscore_suspend(); + if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; } @@ -524,7 +536,7 @@ int hibernation_platform_enter(void) while (1); Power_up: - sysdev_resume(); + syscore_resume(); local_irq_enable(); enable_nonboot_cpus(); @@ -536,7 +548,6 @@ int hibernation_platform_enter(void) Resume_devices: entering_platform_hibernation = false; dpm_resume_end(PMSG_RESTORE); - set_gfp_allowed_mask(saved_mask); resume_console(); Close: @@ -646,6 +657,8 @@ int hibernate(void) swsusp_free(); if (!error) power_down(); + in_suspend = 0; + pm_restore_gfp_mask(); } else { pr_debug("PM: Image restored successfully.\n"); } @@ -964,10 +977,33 @@ static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *att power_attr(image_size); +static ssize_t reserved_size_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", reserved_size); +} + +static ssize_t reserved_size_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t n) +{ + unsigned long size; + + if (sscanf(buf, "%lu", &size) == 1) { + reserved_size = size; + return n; + } + + return -EINVAL; +} + +power_attr(reserved_size); + static struct attribute * g[] = { &disk_attr.attr, &resume_attr.attr, &image_size_attr.attr, + &reserved_size_attr.attr, NULL, }; diff --git a/kernel/power/main.c b/kernel/power/main.c index 7b5db6a8561..2981af4ce7c 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -17,9 +17,6 @@ DEFINE_MUTEX(pm_mutex); -unsigned int pm_flags; -EXPORT_SYMBOL(pm_flags); - #ifdef CONFIG_PM_SLEEP /* Routines for PM-transition notifications */ @@ -227,7 +224,7 @@ power_attr(state); * writing to 'state'. It first should read from 'wakeup_count' and store * the read value. Then, after carrying out its own preparations for the system * transition to a sleep state, it should write the stored value to - * 'wakeup_count'. If that fails, at least one wakeup event has occured since + * 'wakeup_count'. If that fails, at least one wakeup event has occurred since * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it * is allowed to write to 'state', but the transition will be aborted if there * are any wakeup events detected after 'wakeup_count' was written to. @@ -326,7 +323,7 @@ EXPORT_SYMBOL_GPL(pm_wq); static int __init pm_start_workqueue(void) { - pm_wq = alloc_workqueue("pm", WQ_FREEZEABLE, 0); + pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0); return pm_wq ? 0 : -ENOMEM; } @@ -340,6 +337,7 @@ static int __init pm_init(void) if (error) return error; hibernate_image_size_init(); + hibernate_reserved_size_init(); power_kobj = kobject_create_and_add("power", NULL); if (!power_kobj) return -ENOMEM; diff --git a/kernel/power/nvs.c b/kernel/power/nvs.c deleted file mode 100644 index 1836db60bbb..00000000000 --- a/kernel/power/nvs.c +++ /dev/null @@ -1,136 +0,0 @@ -/* - * linux/kernel/power/hibernate_nvs.c - Routines for handling NVS memory - * - * Copyright (C) 2008,2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. - * - * This file is released under the GPLv2. - */ - -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/list.h> -#include <linux/mm.h> -#include <linux/slab.h> -#include <linux/suspend.h> - -/* - * Platforms, like ACPI, may want us to save some memory used by them during - * suspend and to restore the contents of this memory during the subsequent - * resume. The code below implements a mechanism allowing us to do that. - */ - -struct nvs_page { - unsigned long phys_start; - unsigned int size; - void *kaddr; - void *data; - struct list_head node; -}; - -static LIST_HEAD(nvs_list); - -/** - * suspend_nvs_register - register platform NVS memory region to save - * @start - physical address of the region - * @size - size of the region - * - * The NVS region need not be page-aligned (both ends) and we arrange - * things so that the data from page-aligned addresses in this region will - * be copied into separate RAM pages. - */ -int suspend_nvs_register(unsigned long start, unsigned long size) -{ - struct nvs_page *entry, *next; - - while (size > 0) { - unsigned int nr_bytes; - - entry = kzalloc(sizeof(struct nvs_page), GFP_KERNEL); - if (!entry) - goto Error; - - list_add_tail(&entry->node, &nvs_list); - entry->phys_start = start; - nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK); - entry->size = (size < nr_bytes) ? size : nr_bytes; - - start += entry->size; - size -= entry->size; - } - return 0; - - Error: - list_for_each_entry_safe(entry, next, &nvs_list, node) { - list_del(&entry->node); - kfree(entry); - } - return -ENOMEM; -} - -/** - * suspend_nvs_free - free data pages allocated for saving NVS regions - */ -void suspend_nvs_free(void) -{ - struct nvs_page *entry; - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) { - free_page((unsigned long)entry->data); - entry->data = NULL; - if (entry->kaddr) { - iounmap(entry->kaddr); - entry->kaddr = NULL; - } - } -} - -/** - * suspend_nvs_alloc - allocate memory necessary for saving NVS regions - */ -int suspend_nvs_alloc(void) -{ - struct nvs_page *entry; - - list_for_each_entry(entry, &nvs_list, node) { - entry->data = (void *)__get_free_page(GFP_KERNEL); - if (!entry->data) { - suspend_nvs_free(); - return -ENOMEM; - } - } - return 0; -} - -/** - * suspend_nvs_save - save NVS memory regions - */ -void suspend_nvs_save(void) -{ - struct nvs_page *entry; - - printk(KERN_INFO "PM: Saving platform NVS memory\n"); - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) { - entry->kaddr = ioremap(entry->phys_start, entry->size); - memcpy(entry->data, entry->kaddr, entry->size); - } -} - -/** - * suspend_nvs_restore - restore NVS memory regions - * - * This function is going to be called with interrupts disabled, so it - * cannot iounmap the virtual addresses used to access the NVS region. - */ -void suspend_nvs_restore(void) -{ - struct nvs_page *entry; - - printk(KERN_INFO "PM: Restoring platform NVS memory\n"); - - list_for_each_entry(entry, &nvs_list, node) - if (entry->data) - memcpy(entry->kaddr, entry->data, entry->size); -} diff --git a/kernel/power/power.h b/kernel/power/power.h index 03634be55f6..9a00a0a2628 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -15,6 +15,7 @@ struct swsusp_info { #ifdef CONFIG_HIBERNATION /* kernel/power/snapshot.c */ +extern void __init hibernate_reserved_size_init(void); extern void __init hibernate_image_size_init(void); #ifdef CONFIG_ARCH_HIBERNATION_HEADER @@ -55,6 +56,7 @@ extern int hibernation_platform_enter(void); #else /* !CONFIG_HIBERNATION */ +static inline void hibernate_reserved_size_init(void) {} static inline void hibernate_image_size_init(void) {} #endif /* !CONFIG_HIBERNATION */ @@ -72,6 +74,8 @@ static struct kobj_attribute _name##_attr = { \ /* Preferred image size in bytes (default 500 MB) */ extern unsigned long image_size; +/* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */ +extern unsigned long reserved_size; extern int in_suspend; extern dev_t swsusp_resume_device; extern sector_t swsusp_resume_block; diff --git a/kernel/power/process.c b/kernel/power/process.c index e50b4c1b2a0..0cf3a27a6c9 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -22,7 +22,7 @@ */ #define TIMEOUT (20 * HZ) -static inline int freezeable(struct task_struct * p) +static inline int freezable(struct task_struct * p) { if ((p == current) || (p->flags & PF_NOFREEZE) || @@ -53,7 +53,7 @@ static int try_to_freeze_tasks(bool sig_only) todo = 0; read_lock(&tasklist_lock); do_each_thread(g, p) { - if (frozen(p) || !freezeable(p)) + if (frozen(p) || !freezable(p)) continue; if (!freeze_task(p, sig_only)) @@ -64,6 +64,12 @@ static int try_to_freeze_tasks(bool sig_only) * perturb a task in TASK_STOPPED or TASK_TRACED. * It is "frozen enough". If the task does wake * up, it will immediately call try_to_freeze. + * + * Because freeze_task() goes through p's + * scheduler lock after setting TIF_FREEZE, it's + * guaranteed that either we see TASK_RUNNING or + * try_to_stop() after schedule() in ptrace/signal + * stop sees TIF_FREEZE. */ if (!task_is_stopped_or_traced(p) && !freezer_should_skip(p)) @@ -79,7 +85,7 @@ static int try_to_freeze_tasks(bool sig_only) if (!todo || time_after(jiffies, end_time)) break; - if (!pm_check_wakeup_events()) { + if (pm_wakeup_pending()) { wakeup = true; break; } @@ -161,7 +167,7 @@ static void thaw_tasks(bool nosig_only) read_lock(&tasklist_lock); do_each_thread(g, p) { - if (!freezeable(p)) + if (!freezable(p)) continue; if (nosig_only && should_send_signal(p)) diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 0dac75ea445..ace55889f70 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -41,6 +41,18 @@ static void swsusp_set_page_forbidden(struct page *); static void swsusp_unset_page_forbidden(struct page *); /* + * Number of bytes to reserve for memory allocations made by device drivers + * from their ->freeze() and ->freeze_noirq() callbacks so that they don't + * cause image creation to fail (tunable via /sys/power/reserved_size). + */ +unsigned long reserved_size; + +void __init hibernate_reserved_size_init(void) +{ + reserved_size = SPARE_PAGES * PAGE_SIZE; +} + +/* * Preferred image size in bytes (tunable via /sys/power/image_size). * When it is set to N, swsusp will do its best to ensure the image * size will not exceed N bytes, but if that is impossible, it will @@ -1263,11 +1275,13 @@ static unsigned long minimum_image_size(unsigned long saveable) * frame in use. We also need a number of page frames to be free during * hibernation for allocations made while saving the image and for device * drivers, in case they need to allocate memory from their hibernation - * callbacks (these two numbers are given by PAGES_FOR_IO and SPARE_PAGES, - * respectively, both of which are rough estimates). To make this happen, we - * compute the total number of available page frames and allocate at least + * callbacks (these two numbers are given by PAGES_FOR_IO (which is a rough + * estimate) and reserverd_size divided by PAGE_SIZE (which is tunable through + * /sys/power/reserved_size, respectively). To make this happen, we compute the + * total number of available page frames and allocate at least * - * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 + 2 * SPARE_PAGES + * ([page frames total] + PAGES_FOR_IO + [metadata pages]) / 2 + * + 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE) * * of them, which corresponds to the maximum size of a hibernation image. * @@ -1322,7 +1336,8 @@ int hibernate_preallocate_memory(void) count -= totalreserve_pages; /* Compute the maximum number of saveable pages to leave in memory. */ - max_size = (count - (size + PAGES_FOR_IO)) / 2 - 2 * SPARE_PAGES; + max_size = (count - (size + PAGES_FOR_IO)) / 2 + - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE); /* Compute the desired number of image pages specified by image_size. */ size = DIV_ROUND_UP(image_size, PAGE_SIZE); if (size > max_size) @@ -1519,11 +1534,8 @@ static int swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, unsigned int nr_pages, unsigned int nr_highmem) { - int error = 0; - if (nr_highmem > 0) { - error = get_highmem_buffer(PG_ANY); - if (error) + if (get_highmem_buffer(PG_ANY)) goto err_out; if (nr_highmem > alloc_highmem) { nr_highmem -= alloc_highmem; @@ -1546,7 +1558,7 @@ swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm, err_out: swsusp_free(); - return error; + return -ENOMEM; } asmlinkage int swsusp_save(void) diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 7335952ee47..1c41ba21541 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -22,6 +22,8 @@ #include <linux/mm.h> #include <linux/slab.h> #include <linux/suspend.h> +#include <linux/syscore_ops.h> +#include <trace/events/power.h> #include "power.h" @@ -30,13 +32,13 @@ const char *const pm_states[PM_SUSPEND_MAX] = { [PM_SUSPEND_MEM] = "mem", }; -static struct platform_suspend_ops *suspend_ops; +static const struct platform_suspend_ops *suspend_ops; /** * suspend_set_ops - Set the global suspend method table. * @ops: Pointer to ops structure. */ -void suspend_set_ops(struct platform_suspend_ops *ops) +void suspend_set_ops(const struct platform_suspend_ops *ops) { mutex_lock(&pm_mutex); suspend_ops = ops; @@ -161,13 +163,13 @@ static int suspend_enter(suspend_state_t state) arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); - error = sysdev_suspend(PMSG_SUSPEND); + error = syscore_suspend(); if (!error) { - if (!suspend_test(TEST_CORE) && pm_check_wakeup_events()) { + if (!(suspend_test(TEST_CORE) || pm_wakeup_pending())) { error = suspend_ops->enter(state); events_check_enabled = false; } - sysdev_resume(); + syscore_resume(); } arch_suspend_enable_irqs(); @@ -197,18 +199,17 @@ static int suspend_enter(suspend_state_t state) int suspend_devices_and_enter(suspend_state_t state) { int error; - gfp_t saved_mask; if (!suspend_ops) return -ENOSYS; + trace_machine_suspend(state); if (suspend_ops->begin) { error = suspend_ops->begin(state); if (error) goto Close; } suspend_console(); - saved_mask = clear_gfp_allowed_mask(GFP_IOFS); suspend_test_start(); error = dpm_suspend_start(PMSG_SUSPEND); if (error) { @@ -219,17 +220,17 @@ int suspend_devices_and_enter(suspend_state_t state) if (suspend_test(TEST_DEVICES)) goto Recover_platform; - suspend_enter(state); + error = suspend_enter(state); Resume_devices: suspend_test_start(); dpm_resume_end(PMSG_RESUME); suspend_test_finish("resume devices"); - set_gfp_allowed_mask(saved_mask); resume_console(); Close: if (suspend_ops->end) suspend_ops->end(); + trace_machine_suspend(PWR_EVENT_EXIT); return error; Recover_platform: @@ -285,7 +286,9 @@ int enter_state(suspend_state_t state) goto Finish; pr_debug("PM: Entering %s sleep\n", pm_states[state]); + pm_restrict_gfp_mask(); error = suspend_devices_and_enter(state); + pm_restore_gfp_mask(); Finish: pr_debug("PM: Finishing wakeup.\n"); diff --git a/kernel/power/swap.c b/kernel/power/swap.c index a0e4a86ccf9..7c97c3a0eee 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -6,6 +6,7 @@ * * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz> * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> + * Copyright (C) 2010 Bojan Smojver <bojan@rexursive.com> * * This file is released under the GPLv2. * @@ -29,7 +30,7 @@ #include "power.h" -#define HIBERNATE_SIG "LINHIB0001" +#define HIBERNATE_SIG "S1SUSPEND" /* * The swap map is a data structure used for keeping track of each page @@ -223,7 +224,7 @@ static int swsusp_swap_check(void) return res; root_swap = res; - res = blkdev_get(hib_resume_bdev, FMODE_WRITE); + res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL); if (res) return res; @@ -753,30 +754,43 @@ static int load_image_lzo(struct swap_map_handle *handle, { unsigned int m; int error = 0; + struct bio *bio; struct timeval start; struct timeval stop; unsigned nr_pages; - size_t off, unc_len, cmp_len; - unsigned char *unc, *cmp, *page; + size_t i, off, unc_len, cmp_len; + unsigned char *unc, *cmp, *page[LZO_CMP_PAGES]; - page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); - if (!page) { - printk(KERN_ERR "PM: Failed to allocate LZO page\n"); - return -ENOMEM; + for (i = 0; i < LZO_CMP_PAGES; i++) { + page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); + if (!page[i]) { + printk(KERN_ERR "PM: Failed to allocate LZO page\n"); + + while (i) + free_page((unsigned long)page[--i]); + + return -ENOMEM; + } } unc = vmalloc(LZO_UNC_SIZE); if (!unc) { printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n"); - free_page((unsigned long)page); + + for (i = 0; i < LZO_CMP_PAGES; i++) + free_page((unsigned long)page[i]); + return -ENOMEM; } cmp = vmalloc(LZO_CMP_SIZE); if (!cmp) { printk(KERN_ERR "PM: Failed to allocate LZO compressed\n"); + vfree(unc); - free_page((unsigned long)page); + for (i = 0; i < LZO_CMP_PAGES; i++) + free_page((unsigned long)page[i]); + return -ENOMEM; } @@ -787,6 +801,7 @@ static int load_image_lzo(struct swap_map_handle *handle, if (!m) m = 1; nr_pages = 0; + bio = NULL; do_gettimeofday(&start); error = snapshot_write_next(snapshot); @@ -794,11 +809,11 @@ static int load_image_lzo(struct swap_map_handle *handle, goto out_finish; for (;;) { - error = swap_read_page(handle, page, NULL); /* sync */ + error = swap_read_page(handle, page[0], NULL); /* sync */ if (error) break; - cmp_len = *(size_t *)page; + cmp_len = *(size_t *)page[0]; if (unlikely(!cmp_len || cmp_len > lzo1x_worst_compress(LZO_UNC_SIZE))) { printk(KERN_ERR "PM: Invalid LZO compressed length\n"); @@ -806,13 +821,20 @@ static int load_image_lzo(struct swap_map_handle *handle, break; } - memcpy(cmp, page, PAGE_SIZE); - for (off = PAGE_SIZE; off < LZO_HEADER + cmp_len; off += PAGE_SIZE) { - error = swap_read_page(handle, page, NULL); /* sync */ + for (off = PAGE_SIZE, i = 1; + off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) { + error = swap_read_page(handle, page[i], &bio); if (error) goto out_finish; + } - memcpy(cmp + off, page, PAGE_SIZE); + error = hib_wait_on_bio_chain(&bio); /* need all data now */ + if (error) + goto out_finish; + + for (off = 0, i = 0; + off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) { + memcpy(cmp + off, page[i], PAGE_SIZE); } unc_len = LZO_UNC_SIZE; @@ -857,7 +879,8 @@ out_finish: vfree(cmp); vfree(unc); - free_page((unsigned long)page); + for (i = 0; i < LZO_CMP_PAGES; i++) + free_page((unsigned long)page[i]); return error; } @@ -865,7 +888,7 @@ out_finish: /** * swsusp_read - read the hibernation image. * @flags_p: flags passed by the "frozen" kernel in the image header should - * be written into this memeory location + * be written into this memory location */ int swsusp_read(unsigned int *flags_p) @@ -907,7 +930,8 @@ int swsusp_check(void) { int error; - hib_resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); + hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, + FMODE_READ, NULL); if (!IS_ERR(hib_resume_bdev)) { set_blocksize(hib_resume_bdev, PAGE_SIZE); clear_page(swsusp_header); diff --git a/kernel/power/user.c b/kernel/power/user.c index e819e17877c..7d02d33be69 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -135,9 +135,11 @@ static int snapshot_release(struct inode *inode, struct file *filp) free_basic_memory_bitmaps(); data = filp->private_data; free_all_swap_pages(data->swap); - if (data->frozen) + if (data->frozen) { + pm_restore_gfp_mask(); thaw_processes(); - pm_notifier_call_chain(data->mode == O_WRONLY ? + } + pm_notifier_call_chain(data->mode == O_RDONLY ? PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); @@ -263,6 +265,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, case SNAPSHOT_UNFREEZE: if (!data->frozen || data->ready) break; + pm_restore_gfp_mask(); thaw_processes(); usermodehelper_enable(); data->frozen = 0; @@ -275,6 +278,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = -EPERM; break; } + pm_restore_gfp_mask(); error = hibernation_snapshot(data->platform_support); if (!error) error = put_user(in_suspend, (int __user *)arg); @@ -377,6 +381,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, * PM_HIBERNATION_PREPARE */ error = suspend_devices_and_enter(PM_SUSPEND_MEM); + data->ready = 0; break; case SNAPSHOT_PLATFORM_SUPPORT: diff --git a/kernel/printk.c b/kernel/printk.c index b2ebaee8c37..da8ca817eae 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -39,16 +39,11 @@ #include <linux/syslog.h> #include <linux/cpu.h> #include <linux/notifier.h> +#include <linux/rculist.h> #include <asm/uaccess.h> /* - * for_each_console() allows you to iterate on each console - */ -#define for_each_console(con) \ - for (con = console_drivers; con != NULL; con = con->next) - -/* * Architectures can override it: */ void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...) @@ -58,7 +53,7 @@ void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...) #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT) /* printk's without a loglevel use this.. */ -#define DEFAULT_MESSAGE_LOGLEVEL 4 /* KERN_WARNING */ +#define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL /* We show everything that is MORE important than this.. */ #define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */ @@ -102,7 +97,7 @@ static int console_locked, console_suspended; /* * logbuf_lock protects log_buf, log_start, log_end, con_start and logged_chars * It is also used in interesting ways to provide interlocking in - * release_console_sem(). + * console_unlock();. */ static DEFINE_SPINLOCK(logbuf_lock); @@ -118,6 +113,11 @@ static unsigned con_start; /* Index into log_buf: next char to be sent to consol static unsigned log_end; /* Index into log_buf: most-recently-written-char + 1 */ /* + * If exclusive_console is non-NULL then only this console is to be printed to. + */ +static struct console *exclusive_console; + +/* * Array of consoles built from command line options (console=) */ struct console_cmdline @@ -261,14 +261,55 @@ static inline void boot_delay_msec(void) } #endif +#ifdef CONFIG_SECURITY_DMESG_RESTRICT +int dmesg_restrict = 1; +#else +int dmesg_restrict; +#endif + +static int syslog_action_restricted(int type) +{ + if (dmesg_restrict) + return 1; + /* Unless restricted, we allow "read all" and "get buffer size" for everybody */ + return type != SYSLOG_ACTION_READ_ALL && type != SYSLOG_ACTION_SIZE_BUFFER; +} + +static int check_syslog_permissions(int type, bool from_file) +{ + /* + * If this is from /proc/kmsg and we've already opened it, then we've + * already done the capabilities checks at open time. + */ + if (from_file && type != SYSLOG_ACTION_OPEN) + return 0; + + if (syslog_action_restricted(type)) { + if (capable(CAP_SYSLOG)) + return 0; + /* For historical reasons, accept CAP_SYS_ADMIN too, with a warning */ + if (capable(CAP_SYS_ADMIN)) { + WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN " + "but no CAP_SYSLOG (deprecated).\n"); + return 0; + } + return -EPERM; + } + return 0; +} + int do_syslog(int type, char __user *buf, int len, bool from_file) { unsigned i, j, limit, count; int do_clear = 0; char c; - int error = 0; + int error; + + error = check_syslog_permissions(type, from_file); + if (error) + goto out; - error = security_syslog(type, from_file); + error = security_syslog(type); if (error) return error; @@ -440,6 +481,8 @@ static void __call_console_drivers(unsigned start, unsigned end) struct console *con; for_each_console(con) { + if (exclusive_console && con != exclusive_console) + continue; if ((con->flags & CON_ENABLED) && con->write && (cpu_online(smp_processor_id()) || (con->flags & CON_ANYTIME))) @@ -479,9 +522,74 @@ static void _call_console_drivers(unsigned start, } /* + * Parse the syslog header <[0-9]*>. The decimal value represents 32bit, the + * lower 3 bit are the log level, the rest are the log facility. In case + * userspace passes usual userspace syslog messages to /dev/kmsg or + * /dev/ttyprintk, the log prefix might contain the facility. Printk needs + * to extract the correct log level for in-kernel processing, and not mangle + * the original value. + * + * If a prefix is found, the length of the prefix is returned. If 'level' is + * passed, it will be filled in with the log level without a possible facility + * value. If 'special' is passed, the special printk prefix chars are accepted + * and returned. If no valid header is found, 0 is returned and the passed + * variables are not touched. + */ +static size_t log_prefix(const char *p, unsigned int *level, char *special) +{ + unsigned int lev = 0; + char sp = '\0'; + size_t len; + + if (p[0] != '<' || !p[1]) + return 0; + if (p[2] == '>') { + /* usual single digit level number or special char */ + switch (p[1]) { + case '0' ... '7': + lev = p[1] - '0'; + break; + case 'c': /* KERN_CONT */ + case 'd': /* KERN_DEFAULT */ + sp = p[1]; + break; + default: + return 0; + } + len = 3; + } else { + /* multi digit including the level and facility number */ + char *endp = NULL; + + if (p[1] < '0' && p[1] > '9') + return 0; + + lev = (simple_strtoul(&p[1], &endp, 10) & 7); + if (endp == NULL || endp[0] != '>') + return 0; + len = (endp + 1) - p; + } + + /* do not accept special char if not asked for */ + if (sp && !special) + return 0; + + if (special) { + *special = sp; + /* return special char, do not touch level */ + if (sp) + return len; + } + + if (level) + *level = lev; + return len; +} + +/* * Call the console drivers, asking them to write out * log_buf[start] to log_buf[end - 1]. - * The console_sem must be held. + * The console_lock must be held. */ static void call_console_drivers(unsigned start, unsigned end) { @@ -493,13 +601,9 @@ static void call_console_drivers(unsigned start, unsigned end) cur_index = start; start_print = start; while (cur_index != end) { - if (msg_level < 0 && ((end - cur_index) > 2) && - LOG_BUF(cur_index + 0) == '<' && - LOG_BUF(cur_index + 1) >= '0' && - LOG_BUF(cur_index + 1) <= '7' && - LOG_BUF(cur_index + 2) == '>') { - msg_level = LOG_BUF(cur_index + 1) - '0'; - cur_index += 3; + if (msg_level < 0 && ((end - cur_index) > 2)) { + /* strip log prefix */ + cur_index += log_prefix(&LOG_BUF(cur_index), &msg_level, NULL); start_print = cur_index; } while (cur_index != end) { @@ -584,11 +688,11 @@ static int have_callable_console(void) * * This is printk(). It can be called from any context. We want it to work. * - * We try to grab the console_sem. If we succeed, it's easy - we log the output and + * We try to grab the console_lock. If we succeed, it's easy - we log the output and * call the console drivers. If we fail to get the semaphore we place the output * into the log buffer and return. The current holder of the console_sem will - * notice the new output in release_console_sem() and will send it to the - * consoles before releasing the semaphore. + * notice the new output in console_unlock(); and will send it to the + * consoles before releasing the lock. * * One effect of this deferred printing is that code which calls printk() and * then changes console_loglevel may break. This is because console_loglevel @@ -639,19 +743,19 @@ static inline int can_use_console(unsigned int cpu) /* * Try to get console ownership to actually show the kernel * messages from a 'printk'. Return true (and with the - * console_semaphore held, and 'console_locked' set) if it + * console_lock held, and 'console_locked' set) if it * is successful, false otherwise. * * This gets called with the 'logbuf_lock' spinlock held and * interrupts disabled. It should return with 'lockbuf_lock' * released but interrupts still disabled. */ -static int acquire_console_semaphore_for_printk(unsigned int cpu) +static int console_trylock_for_printk(unsigned int cpu) __releases(&logbuf_lock) { int retval = 0; - if (!try_acquire_console_sem()) { + if (console_trylock()) { retval = 1; /* @@ -697,6 +801,8 @@ asmlinkage int vprintk(const char *fmt, va_list args) unsigned long flags; int this_cpu; char *p; + size_t plen; + char special; boot_delay_msec(); printk_delay(); @@ -737,45 +843,52 @@ asmlinkage int vprintk(const char *fmt, va_list args) printed_len += vscnprintf(printk_buf + printed_len, sizeof(printk_buf) - printed_len, fmt, args); - p = printk_buf; - /* Do we have a loglevel in the string? */ - if (p[0] == '<') { - unsigned char c = p[1]; - if (c && p[2] == '>') { - switch (c) { - case '0' ... '7': /* loglevel */ - current_log_level = c - '0'; - /* Fallthrough - make sure we're on a new line */ - case 'd': /* KERN_DEFAULT */ - if (!new_text_line) { - emit_log_char('\n'); - new_text_line = 1; - } - /* Fallthrough - skip the loglevel */ - case 'c': /* KERN_CONT */ - p += 3; - break; + /* Read log level and handle special printk prefix */ + plen = log_prefix(p, ¤t_log_level, &special); + if (plen) { + p += plen; + + switch (special) { + case 'c': /* Strip <c> KERN_CONT, continue line */ + plen = 0; + break; + case 'd': /* Strip <d> KERN_DEFAULT, start new line */ + plen = 0; + default: + if (!new_text_line) { + emit_log_char('\n'); + new_text_line = 1; } } } /* - * Copy the output into log_buf. If the caller didn't provide - * appropriate log level tags, we insert them here + * Copy the output into log_buf. If the caller didn't provide + * the appropriate log prefix, we insert them here */ - for ( ; *p; p++) { + for (; *p; p++) { if (new_text_line) { - /* Always output the token */ - emit_log_char('<'); - emit_log_char(current_log_level + '0'); - emit_log_char('>'); - printed_len += 3; new_text_line = 0; + if (plen) { + /* Copy original log prefix */ + int i; + + for (i = 0; i < plen; i++) + emit_log_char(printk_buf[i]); + printed_len += plen; + } else { + /* Add log prefix */ + emit_log_char('<'); + emit_log_char(current_log_level + '0'); + emit_log_char('>'); + printed_len += 3; + } + if (printk_time) { - /* Follow the token with the time */ + /* Add the current time stamp */ char tbuf[50], *tp; unsigned tlen; unsigned long long t; @@ -807,12 +920,12 @@ asmlinkage int vprintk(const char *fmt, va_list args) * actual magic (print out buffers, wake up klogd, * etc). * - * The acquire_console_semaphore_for_printk() function + * The console_trylock_for_printk() function * will release 'logbuf_lock' regardless of whether it * actually gets the semaphore or not. */ - if (acquire_console_semaphore_for_printk(this_cpu)) - release_console_sem(); + if (console_trylock_for_printk(this_cpu)) + console_unlock(); lockdep_on(); out_restore_irqs: @@ -973,7 +1086,7 @@ void suspend_console(void) if (!console_suspend_enabled) return; printk("Suspending console(s) (use no_console_suspend to debug)\n"); - acquire_console_sem(); + console_lock(); console_suspended = 1; up(&console_sem); } @@ -984,7 +1097,7 @@ void resume_console(void) return; down(&console_sem); console_suspended = 0; - release_console_sem(); + console_unlock(); } /** @@ -1007,21 +1120,21 @@ static int __cpuinit console_cpu_notify(struct notifier_block *self, case CPU_DYING: case CPU_DOWN_FAILED: case CPU_UP_CANCELED: - acquire_console_sem(); - release_console_sem(); + console_lock(); + console_unlock(); } return NOTIFY_OK; } /** - * acquire_console_sem - lock the console system for exclusive use. + * console_lock - lock the console system for exclusive use. * - * Acquires a semaphore which guarantees that the caller has + * Acquires a lock which guarantees that the caller has * exclusive access to the console system and the console_drivers list. * * Can sleep, returns nothing. */ -void acquire_console_sem(void) +void console_lock(void) { BUG_ON(in_interrupt()); down(&console_sem); @@ -1030,21 +1143,29 @@ void acquire_console_sem(void) console_locked = 1; console_may_schedule = 1; } -EXPORT_SYMBOL(acquire_console_sem); +EXPORT_SYMBOL(console_lock); -int try_acquire_console_sem(void) +/** + * console_trylock - try to lock the console system for exclusive use. + * + * Tried to acquire a lock which guarantees that the caller has + * exclusive access to the console system and the console_drivers list. + * + * returns 1 on success, and 0 on failure to acquire the lock. + */ +int console_trylock(void) { if (down_trylock(&console_sem)) - return -1; + return 0; if (console_suspended) { up(&console_sem); - return -1; + return 0; } console_locked = 1; console_may_schedule = 0; - return 0; + return 1; } -EXPORT_SYMBOL(try_acquire_console_sem); +EXPORT_SYMBOL(console_trylock); int is_console_locked(void) { @@ -1055,38 +1176,40 @@ static DEFINE_PER_CPU(int, printk_pending); void printk_tick(void) { - if (__get_cpu_var(printk_pending)) { - __get_cpu_var(printk_pending) = 0; + if (__this_cpu_read(printk_pending)) { + __this_cpu_write(printk_pending, 0); wake_up_interruptible(&log_wait); } } int printk_needs_cpu(int cpu) { - return per_cpu(printk_pending, cpu); + if (cpu_is_offline(cpu)) + printk_tick(); + return __this_cpu_read(printk_pending); } void wake_up_klogd(void) { if (waitqueue_active(&log_wait)) - __raw_get_cpu_var(printk_pending) = 1; + this_cpu_write(printk_pending, 1); } /** - * release_console_sem - unlock the console system + * console_unlock - unlock the console system * - * Releases the semaphore which the caller holds on the console system + * Releases the console_lock which the caller holds on the console system * and the console driver list. * - * While the semaphore was held, console output may have been buffered - * by printk(). If this is the case, release_console_sem() emits - * the output prior to releasing the semaphore. + * While the console_lock was held, console output may have been buffered + * by printk(). If this is the case, console_unlock(); emits + * the output prior to releasing the lock. * * If there is output waiting for klogd, we wake it up. * - * release_console_sem() may be called from any context. + * console_unlock(); may be called from any context. */ -void release_console_sem(void) +void console_unlock(void) { unsigned long flags; unsigned _con_start, _log_end; @@ -1114,12 +1237,17 @@ void release_console_sem(void) local_irq_restore(flags); } console_locked = 0; + + /* Release the exclusive_console once it is used */ + if (unlikely(exclusive_console)) + exclusive_console = NULL; + up(&console_sem); spin_unlock_irqrestore(&logbuf_lock, flags); if (wake_klogd) wake_up_klogd(); } -EXPORT_SYMBOL(release_console_sem); +EXPORT_SYMBOL(console_unlock); /** * console_conditional_schedule - yield the CPU if required @@ -1128,7 +1256,7 @@ EXPORT_SYMBOL(release_console_sem); * if this CPU should yield the CPU to another task, do * so here. * - * Must be called within acquire_console_sem(). + * Must be called within console_lock();. */ void __sched console_conditional_schedule(void) { @@ -1149,14 +1277,14 @@ void console_unblank(void) if (down_trylock(&console_sem) != 0) return; } else - acquire_console_sem(); + console_lock(); console_locked = 1; console_may_schedule = 0; for_each_console(c) if ((c->flags & CON_ENABLED) && c->unblank) c->unblank(); - release_console_sem(); + console_unlock(); } /* @@ -1167,7 +1295,7 @@ struct tty_driver *console_device(int *index) struct console *c; struct tty_driver *driver = NULL; - acquire_console_sem(); + console_lock(); for_each_console(c) { if (!c->device) continue; @@ -1175,7 +1303,7 @@ struct tty_driver *console_device(int *index) if (driver) break; } - release_console_sem(); + console_unlock(); return driver; } @@ -1186,20 +1314,32 @@ struct tty_driver *console_device(int *index) */ void console_stop(struct console *console) { - acquire_console_sem(); + console_lock(); console->flags &= ~CON_ENABLED; - release_console_sem(); + console_unlock(); } EXPORT_SYMBOL(console_stop); void console_start(struct console *console) { - acquire_console_sem(); + console_lock(); console->flags |= CON_ENABLED; - release_console_sem(); + console_unlock(); } EXPORT_SYMBOL(console_start); +static int __read_mostly keep_bootcon; + +static int __init keep_bootcon_setup(char *str) +{ + keep_bootcon = 1; + printk(KERN_INFO "debug: skip boot console de-registration.\n"); + + return 0; +} + +early_param("keep_bootcon", keep_bootcon_setup); + /* * The console driver calls this routine during kernel initialization * to register the console printing procedure with printk() and to @@ -1318,7 +1458,7 @@ void register_console(struct console *newcon) * Put this console in the list - keep the * preferred driver at the head of the list. */ - acquire_console_sem(); + console_lock(); if ((newcon->flags & CON_CONSDEV) || console_drivers == NULL) { newcon->next = console_drivers; console_drivers = newcon; @@ -1330,14 +1470,21 @@ void register_console(struct console *newcon) } if (newcon->flags & CON_PRINTBUFFER) { /* - * release_console_sem() will print out the buffered messages + * console_unlock(); will print out the buffered messages * for us. */ spin_lock_irqsave(&logbuf_lock, flags); con_start = log_start; spin_unlock_irqrestore(&logbuf_lock, flags); + /* + * We're about to replay the log buffer. Only do this to the + * just-registered console to avoid excessive message spam to + * the already-registered consoles. + */ + exclusive_console = newcon; } - release_console_sem(); + console_unlock(); + console_sysfs_notify(); /* * By unregistering the bootconsoles after we enable the real console @@ -1346,7 +1493,9 @@ void register_console(struct console *newcon) * users know there might be something in the kernel's log buffer that * went to the bootconsole (that they do not see on the real console) */ - if (bcon && ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV)) { + if (bcon && + ((newcon->flags & (CON_CONSDEV | CON_BOOT)) == CON_CONSDEV) && + !keep_bootcon) { /* we need to iterate through twice, to make sure we print * everything out, before we unregister the console(s) */ @@ -1373,7 +1522,7 @@ int unregister_console(struct console *console) return braille_unregister_console(console); #endif - acquire_console_sem(); + console_lock(); if (console_drivers == console) { console_drivers=console->next; res = 0; @@ -1395,7 +1544,8 @@ int unregister_console(struct console *console) if (console_drivers != NULL && console->flags & CON_CONSDEV) console_drivers->flags |= CON_CONSDEV; - release_console_sem(); + console_unlock(); + console_sysfs_notify(); return res; } EXPORT_SYMBOL(unregister_console); @@ -1479,7 +1629,7 @@ int kmsg_dump_register(struct kmsg_dumper *dumper) /* Don't allow registering multiple times */ if (!dumper->registered) { dumper->registered = 1; - list_add_tail(&dumper->list, &dump_list); + list_add_tail_rcu(&dumper->list, &dump_list); err = 0; } spin_unlock_irqrestore(&dump_list_lock, flags); @@ -1503,29 +1653,16 @@ int kmsg_dump_unregister(struct kmsg_dumper *dumper) spin_lock_irqsave(&dump_list_lock, flags); if (dumper->registered) { dumper->registered = 0; - list_del(&dumper->list); + list_del_rcu(&dumper->list); err = 0; } spin_unlock_irqrestore(&dump_list_lock, flags); + synchronize_rcu(); return err; } EXPORT_SYMBOL_GPL(kmsg_dump_unregister); -static const char * const kmsg_reasons[] = { - [KMSG_DUMP_OOPS] = "oops", - [KMSG_DUMP_PANIC] = "panic", - [KMSG_DUMP_KEXEC] = "kexec", -}; - -static const char *kmsg_to_str(enum kmsg_dump_reason reason) -{ - if (reason >= ARRAY_SIZE(kmsg_reasons) || reason < 0) - return "unknown"; - - return kmsg_reasons[reason]; -} - /** * kmsg_dump - dump kernel log to kernel message dumpers. * @reason: the reason (oops, panic etc) for dumping @@ -1564,13 +1701,9 @@ void kmsg_dump(enum kmsg_dump_reason reason) l2 = chars; } - if (!spin_trylock_irqsave(&dump_list_lock, flags)) { - printk(KERN_ERR "dump_kmsg: dump list lock is held during %s, skipping dump\n", - kmsg_to_str(reason)); - return; - } - list_for_each_entry(dumper, &dump_list, list) + rcu_read_lock(); + list_for_each_entry_rcu(dumper, &dump_list, list) dumper->dump(dumper, reason, s1, l1, s2, l2); - spin_unlock_irqrestore(&dump_list_lock, flags); + rcu_read_unlock(); } #endif diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 99bbaa3e5b0..dc7ab65f3b3 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -22,6 +22,7 @@ #include <linux/syscalls.h> #include <linux/uaccess.h> #include <linux/regset.h> +#include <linux/hw_breakpoint.h> /* @@ -134,21 +135,24 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode) return 0; rcu_read_lock(); tcred = __task_cred(task); - if ((cred->uid != tcred->euid || - cred->uid != tcred->suid || - cred->uid != tcred->uid || - cred->gid != tcred->egid || - cred->gid != tcred->sgid || - cred->gid != tcred->gid) && - !capable(CAP_SYS_PTRACE)) { - rcu_read_unlock(); - return -EPERM; - } + if (cred->user->user_ns == tcred->user->user_ns && + (cred->uid == tcred->euid && + cred->uid == tcred->suid && + cred->uid == tcred->uid && + cred->gid == tcred->egid && + cred->gid == tcred->sgid && + cred->gid == tcred->gid)) + goto ok; + if (ns_capable(tcred->user->user_ns, CAP_SYS_PTRACE)) + goto ok; + rcu_read_unlock(); + return -EPERM; +ok: rcu_read_unlock(); smp_rmb(); if (task->mm) dumpable = get_dumpable(task->mm); - if (!dumpable && !capable(CAP_SYS_PTRACE)) + if (!dumpable && !task_ns_capable(task, CAP_SYS_PTRACE)) return -EPERM; return security_ptrace_access_check(task, mode); @@ -163,7 +167,7 @@ bool ptrace_may_access(struct task_struct *task, unsigned int mode) return !err; } -int ptrace_attach(struct task_struct *task) +static int ptrace_attach(struct task_struct *task) { int retval; @@ -198,7 +202,7 @@ int ptrace_attach(struct task_struct *task) goto unlock_tasklist; task->ptrace = PT_PTRACED; - if (capable(CAP_SYS_PTRACE)) + if (task_ns_capable(task, CAP_SYS_PTRACE)) task->ptrace |= PT_PTRACE_CAP; __ptrace_link(task, current); @@ -219,7 +223,7 @@ out: * Performs checks and sets PT_PTRACED. * Should be used by all ptrace implementations for PTRACE_TRACEME. */ -int ptrace_traceme(void) +static int ptrace_traceme(void) { int ret = -EPERM; @@ -293,7 +297,7 @@ static bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p) return false; } -int ptrace_detach(struct task_struct *child, unsigned int data) +static int ptrace_detach(struct task_struct *child, unsigned int data) { bool dead = false; @@ -313,7 +317,7 @@ int ptrace_detach(struct task_struct *child, unsigned int data) child->exit_code = data; dead = __ptrace_detach(current, child); if (!child->exit_state) - wake_up_process(child); + wake_up_state(child, TASK_TRACED | TASK_STOPPED); } write_unlock_irq(&tasklist_lock); @@ -876,3 +880,19 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid, return ret; } #endif /* CONFIG_COMPAT */ + +#ifdef CONFIG_HAVE_HW_BREAKPOINT +int ptrace_get_breakpoints(struct task_struct *tsk) +{ + if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt)) + return 0; + + return -1; +} + +void ptrace_put_breakpoints(struct task_struct *tsk) +{ + if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt)) + flush_ptrace_hw_breakpoint(tsk); +} +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ diff --git a/kernel/range.c b/kernel/range.c index 471b66acabb..37fa9b99ad5 100644 --- a/kernel/range.c +++ b/kernel/range.c @@ -119,7 +119,7 @@ static int cmp_range(const void *x1, const void *x2) int clean_sort_range(struct range *range, int az) { - int i, j, k = az - 1, nr_range = 0; + int i, j, k = az - 1, nr_range = az; for (i = 0; i < k; i++) { if (range[i].end) diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index a23a57a976d..7784bd216b6 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -142,10 +142,17 @@ static int rcuhead_fixup_init(void *addr, enum debug_obj_state state) * Ensure that queued callbacks are all executed. * If we detect that we are nested in a RCU read-side critical * section, we should simply fail, otherwise we would deadlock. + * In !PREEMPT configurations, there is no way to tell if we are + * in a RCU read-side critical section or not, so we never + * attempt any fixup and just print a warning. */ +#ifndef CONFIG_PREEMPT + WARN_ON_ONCE(1); + return 0; +#endif if (rcu_preempt_depth() != 0 || preempt_count() != 0 || irqs_disabled()) { - WARN_ON(1); + WARN_ON_ONCE(1); return 0; } rcu_barrier(); @@ -184,10 +191,17 @@ static int rcuhead_fixup_activate(void *addr, enum debug_obj_state state) * Ensure that queued callbacks are all executed. * If we detect that we are nested in a RCU read-side critical * section, we should simply fail, otherwise we would deadlock. + * In !PREEMPT configurations, there is no way to tell if we are + * in a RCU read-side critical section or not, so we never + * attempt any fixup and just print a warning. */ +#ifndef CONFIG_PREEMPT + WARN_ON_ONCE(1); + return 0; +#endif if (rcu_preempt_depth() != 0 || preempt_count() != 0 || irqs_disabled()) { - WARN_ON(1); + WARN_ON_ONCE(1); return 0; } rcu_barrier(); @@ -214,14 +228,17 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state) * Ensure that queued callbacks are all executed. * If we detect that we are nested in a RCU read-side critical * section, we should simply fail, otherwise we would deadlock. + * In !PREEMPT configurations, there is no way to tell if we are + * in a RCU read-side critical section or not, so we never + * attempt any fixup and just print a warning. */ #ifndef CONFIG_PREEMPT - WARN_ON(1); + WARN_ON_ONCE(1); return 0; -#else +#endif if (rcu_preempt_depth() != 0 || preempt_count() != 0 || irqs_disabled()) { - WARN_ON(1); + WARN_ON_ONCE(1); return 0; } rcu_barrier(); @@ -229,7 +246,6 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state) rcu_barrier_bh(); debug_object_free(head, &rcuhead_debug_descr); return 1; -#endif default: return 0; } diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c index d806735342a..421abfd3641 100644 --- a/kernel/rcutiny.c +++ b/kernel/rcutiny.c @@ -36,31 +36,16 @@ #include <linux/time.h> #include <linux/cpu.h> -/* Global control variables for rcupdate callback mechanism. */ -struct rcu_ctrlblk { - struct rcu_head *rcucblist; /* List of pending callbacks (CBs). */ - struct rcu_head **donetail; /* ->next pointer of last "done" CB. */ - struct rcu_head **curtail; /* ->next pointer of last CB. */ -}; - -/* Definition for rcupdate control block. */ -static struct rcu_ctrlblk rcu_sched_ctrlblk = { - .donetail = &rcu_sched_ctrlblk.rcucblist, - .curtail = &rcu_sched_ctrlblk.rcucblist, -}; - -static struct rcu_ctrlblk rcu_bh_ctrlblk = { - .donetail = &rcu_bh_ctrlblk.rcucblist, - .curtail = &rcu_bh_ctrlblk.rcucblist, -}; - -#ifdef CONFIG_DEBUG_LOCK_ALLOC -int rcu_scheduler_active __read_mostly; -EXPORT_SYMBOL_GPL(rcu_scheduler_active); -#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ +/* Controls for rcu_kthread() kthread, replacing RCU_SOFTIRQ used previously. */ +static struct task_struct *rcu_kthread_task; +static DECLARE_WAIT_QUEUE_HEAD(rcu_kthread_wq); +static unsigned long have_rcu_kthread_work; /* Forward declarations for rcutiny_plugin.h. */ -static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp); +struct rcu_ctrlblk; +static void invoke_rcu_kthread(void); +static void rcu_process_callbacks(struct rcu_ctrlblk *rcp); +static int rcu_kthread(void *arg); static void __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), struct rcu_ctrlblk *rcp); @@ -94,36 +79,45 @@ void rcu_exit_nohz(void) #endif /* #ifdef CONFIG_NO_HZ */ /* - * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). - * Also disable irqs to avoid confusion due to interrupt handlers + * Helper function for rcu_sched_qs() and rcu_bh_qs(). + * Also irqs are disabled to avoid confusion due to interrupt handlers * invoking call_rcu(). */ static int rcu_qsctr_help(struct rcu_ctrlblk *rcp) { - unsigned long flags; - - local_irq_save(flags); if (rcp->rcucblist != NULL && rcp->donetail != rcp->curtail) { rcp->donetail = rcp->curtail; - local_irq_restore(flags); return 1; } - local_irq_restore(flags); return 0; } /* + * Wake up rcu_kthread() to process callbacks now eligible for invocation + * or to boost readers. + */ +static void invoke_rcu_kthread(void) +{ + have_rcu_kthread_work = 1; + wake_up(&rcu_kthread_wq); +} + +/* * Record an rcu quiescent state. And an rcu_bh quiescent state while we * are at it, given that any rcu quiescent state is also an rcu_bh * quiescent state. Use "+" instead of "||" to defeat short circuiting. */ void rcu_sched_qs(int cpu) { + unsigned long flags; + + local_irq_save(flags); if (rcu_qsctr_help(&rcu_sched_ctrlblk) + rcu_qsctr_help(&rcu_bh_ctrlblk)) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_kthread(); + local_irq_restore(flags); } /* @@ -131,8 +125,12 @@ void rcu_sched_qs(int cpu) */ void rcu_bh_qs(int cpu) { + unsigned long flags; + + local_irq_save(flags); if (rcu_qsctr_help(&rcu_bh_ctrlblk)) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_kthread(); + local_irq_restore(flags); } /* @@ -152,13 +150,14 @@ void rcu_check_callbacks(int cpu, int user) } /* - * Helper function for rcu_process_callbacks() that operates on the - * specified rcu_ctrlkblk structure. + * Invoke the RCU callbacks on the specified rcu_ctrlkblk structure + * whose grace period has elapsed. */ -static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) +static void rcu_process_callbacks(struct rcu_ctrlblk *rcp) { struct rcu_head *next, *list; unsigned long flags; + RCU_TRACE(int cb_count = 0); /* If no RCU callbacks ready to invoke, just return. */ if (&rcp->rcucblist == rcp->donetail) @@ -180,19 +179,45 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) next = list->next; prefetch(next); debug_rcu_head_unqueue(list); - list->func(list); + local_bh_disable(); + __rcu_reclaim(list); + local_bh_enable(); list = next; + RCU_TRACE(cb_count++); } + RCU_TRACE(rcu_trace_sub_qlen(rcp, cb_count)); } /* - * Invoke any callbacks whose grace period has completed. + * This kthread invokes RCU callbacks whose grace periods have + * elapsed. It is awakened as needed, and takes the place of the + * RCU_SOFTIRQ that was used previously for this purpose. + * This is a kthread, but it is never stopped, at least not until + * the system goes down. */ -static void rcu_process_callbacks(struct softirq_action *unused) +static int rcu_kthread(void *arg) { - __rcu_process_callbacks(&rcu_sched_ctrlblk); - __rcu_process_callbacks(&rcu_bh_ctrlblk); - rcu_preempt_process_callbacks(); + unsigned long work; + unsigned long morework; + unsigned long flags; + + for (;;) { + wait_event_interruptible(rcu_kthread_wq, + have_rcu_kthread_work != 0); + morework = rcu_boost(); + local_irq_save(flags); + work = have_rcu_kthread_work; + have_rcu_kthread_work = morework; + local_irq_restore(flags); + if (work) { + rcu_process_callbacks(&rcu_sched_ctrlblk); + rcu_process_callbacks(&rcu_bh_ctrlblk); + rcu_preempt_process_callbacks(); + } + schedule_timeout_interruptible(1); /* Leave CPU for others. */ + } + + return 0; /* Not reached, but needed to shut gcc up. */ } /* @@ -230,6 +255,7 @@ static void __call_rcu(struct rcu_head *head, local_irq_save(flags); *rcp->curtail = head; rcp->curtail = &head->next; + RCU_TRACE(rcp->qlen++); local_irq_restore(flags); } @@ -282,7 +308,16 @@ void rcu_barrier_sched(void) } EXPORT_SYMBOL_GPL(rcu_barrier_sched); -void __init rcu_init(void) +/* + * Spawn the kthread that invokes RCU callbacks. + */ +static int __init rcu_spawn_kthreads(void) { - open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); + struct sched_param sp; + + rcu_kthread_task = kthread_run(rcu_kthread, NULL, "rcu_kthread"); + sp.sched_priority = RCU_BOOST_PRIO; + sched_setscheduler_nocheck(rcu_kthread_task, SCHED_FIFO, &sp); + return 0; } +early_initcall(rcu_spawn_kthreads); diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h index 6ceca4f745f..f259c676195 100644 --- a/kernel/rcutiny_plugin.h +++ b/kernel/rcutiny_plugin.h @@ -22,6 +22,40 @@ * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com> */ +#include <linux/kthread.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +#ifdef CONFIG_RCU_TRACE +#define RCU_TRACE(stmt) stmt +#else /* #ifdef CONFIG_RCU_TRACE */ +#define RCU_TRACE(stmt) +#endif /* #else #ifdef CONFIG_RCU_TRACE */ + +/* Global control variables for rcupdate callback mechanism. */ +struct rcu_ctrlblk { + struct rcu_head *rcucblist; /* List of pending callbacks (CBs). */ + struct rcu_head **donetail; /* ->next pointer of last "done" CB. */ + struct rcu_head **curtail; /* ->next pointer of last CB. */ + RCU_TRACE(long qlen); /* Number of pending CBs. */ +}; + +/* Definition for rcupdate control block. */ +static struct rcu_ctrlblk rcu_sched_ctrlblk = { + .donetail = &rcu_sched_ctrlblk.rcucblist, + .curtail = &rcu_sched_ctrlblk.rcucblist, +}; + +static struct rcu_ctrlblk rcu_bh_ctrlblk = { + .donetail = &rcu_bh_ctrlblk.rcucblist, + .curtail = &rcu_bh_ctrlblk.rcucblist, +}; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +int rcu_scheduler_active __read_mostly; +EXPORT_SYMBOL_GPL(rcu_scheduler_active); +#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ + #ifdef CONFIG_TINY_PREEMPT_RCU #include <linux/delay.h> @@ -46,17 +80,50 @@ struct rcu_preempt_ctrlblk { struct list_head *gp_tasks; /* Pointer to the first task blocking the */ /* current grace period, or NULL if there */ - /* is not such task. */ + /* is no such task. */ struct list_head *exp_tasks; /* Pointer to first task blocking the */ /* current expedited grace period, or NULL */ /* if there is no such task. If there */ /* is no current expedited grace period, */ /* then there cannot be any such task. */ +#ifdef CONFIG_RCU_BOOST + struct list_head *boost_tasks; + /* Pointer to first task that needs to be */ + /* priority-boosted, or NULL if no priority */ + /* boosting is needed. If there is no */ + /* current or expedited grace period, there */ + /* can be no such task. */ +#endif /* #ifdef CONFIG_RCU_BOOST */ u8 gpnum; /* Current grace period. */ u8 gpcpu; /* Last grace period blocked by the CPU. */ u8 completed; /* Last grace period completed. */ /* If all three are equal, RCU is idle. */ +#ifdef CONFIG_RCU_BOOST + unsigned long boost_time; /* When to start boosting (jiffies) */ +#endif /* #ifdef CONFIG_RCU_BOOST */ +#ifdef CONFIG_RCU_TRACE + unsigned long n_grace_periods; +#ifdef CONFIG_RCU_BOOST + unsigned long n_tasks_boosted; + /* Total number of tasks boosted. */ + unsigned long n_exp_boosts; + /* Number of tasks boosted for expedited GP. */ + unsigned long n_normal_boosts; + /* Number of tasks boosted for normal GP. */ + unsigned long n_balk_blkd_tasks; + /* Refused to boost: no blocked tasks. */ + unsigned long n_balk_exp_gp_tasks; + /* Refused to boost: nothing blocking GP. */ + unsigned long n_balk_boost_tasks; + /* Refused to boost: already boosting. */ + unsigned long n_balk_notyet; + /* Refused to boost: not yet time. */ + unsigned long n_balk_nos; + /* Refused to boost: not sure why, though. */ + /* This can happen due to race conditions. */ +#endif /* #ifdef CONFIG_RCU_BOOST */ +#endif /* #ifdef CONFIG_RCU_TRACE */ }; static struct rcu_preempt_ctrlblk rcu_preempt_ctrlblk = { @@ -122,6 +189,197 @@ static int rcu_preempt_gp_in_progress(void) } /* + * Advance a ->blkd_tasks-list pointer to the next entry, instead + * returning NULL if at the end of the list. + */ +static struct list_head *rcu_next_node_entry(struct task_struct *t) +{ + struct list_head *np; + + np = t->rcu_node_entry.next; + if (np == &rcu_preempt_ctrlblk.blkd_tasks) + np = NULL; + return np; +} + +#ifdef CONFIG_RCU_TRACE + +#ifdef CONFIG_RCU_BOOST +static void rcu_initiate_boost_trace(void); +#endif /* #ifdef CONFIG_RCU_BOOST */ + +/* + * Dump additional statistice for TINY_PREEMPT_RCU. + */ +static void show_tiny_preempt_stats(struct seq_file *m) +{ + seq_printf(m, "rcu_preempt: qlen=%ld gp=%lu g%u/p%u/c%u tasks=%c%c%c\n", + rcu_preempt_ctrlblk.rcb.qlen, + rcu_preempt_ctrlblk.n_grace_periods, + rcu_preempt_ctrlblk.gpnum, + rcu_preempt_ctrlblk.gpcpu, + rcu_preempt_ctrlblk.completed, + "T."[list_empty(&rcu_preempt_ctrlblk.blkd_tasks)], + "N."[!rcu_preempt_ctrlblk.gp_tasks], + "E."[!rcu_preempt_ctrlblk.exp_tasks]); +#ifdef CONFIG_RCU_BOOST + seq_printf(m, "%sttb=%c ntb=%lu neb=%lu nnb=%lu j=%04x bt=%04x\n", + " ", + "B."[!rcu_preempt_ctrlblk.boost_tasks], + rcu_preempt_ctrlblk.n_tasks_boosted, + rcu_preempt_ctrlblk.n_exp_boosts, + rcu_preempt_ctrlblk.n_normal_boosts, + (int)(jiffies & 0xffff), + (int)(rcu_preempt_ctrlblk.boost_time & 0xffff)); + seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu ny=%lu nos=%lu\n", + " balk", + rcu_preempt_ctrlblk.n_balk_blkd_tasks, + rcu_preempt_ctrlblk.n_balk_exp_gp_tasks, + rcu_preempt_ctrlblk.n_balk_boost_tasks, + rcu_preempt_ctrlblk.n_balk_notyet, + rcu_preempt_ctrlblk.n_balk_nos); +#endif /* #ifdef CONFIG_RCU_BOOST */ +} + +#endif /* #ifdef CONFIG_RCU_TRACE */ + +#ifdef CONFIG_RCU_BOOST + +#include "rtmutex_common.h" + +/* + * Carry out RCU priority boosting on the task indicated by ->boost_tasks, + * and advance ->boost_tasks to the next task in the ->blkd_tasks list. + */ +static int rcu_boost(void) +{ + unsigned long flags; + struct rt_mutex mtx; + struct task_struct *t; + struct list_head *tb; + + if (rcu_preempt_ctrlblk.boost_tasks == NULL && + rcu_preempt_ctrlblk.exp_tasks == NULL) + return 0; /* Nothing to boost. */ + + raw_local_irq_save(flags); + + /* + * Recheck with irqs disabled: all tasks in need of boosting + * might exit their RCU read-side critical sections on their own + * if we are preempted just before disabling irqs. + */ + if (rcu_preempt_ctrlblk.boost_tasks == NULL && + rcu_preempt_ctrlblk.exp_tasks == NULL) { + raw_local_irq_restore(flags); + return 0; + } + + /* + * Preferentially boost tasks blocking expedited grace periods. + * This cannot starve the normal grace periods because a second + * expedited grace period must boost all blocked tasks, including + * those blocking the pre-existing normal grace period. + */ + if (rcu_preempt_ctrlblk.exp_tasks != NULL) { + tb = rcu_preempt_ctrlblk.exp_tasks; + RCU_TRACE(rcu_preempt_ctrlblk.n_exp_boosts++); + } else { + tb = rcu_preempt_ctrlblk.boost_tasks; + RCU_TRACE(rcu_preempt_ctrlblk.n_normal_boosts++); + } + RCU_TRACE(rcu_preempt_ctrlblk.n_tasks_boosted++); + + /* + * We boost task t by manufacturing an rt_mutex that appears to + * be held by task t. We leave a pointer to that rt_mutex where + * task t can find it, and task t will release the mutex when it + * exits its outermost RCU read-side critical section. Then + * simply acquiring this artificial rt_mutex will boost task + * t's priority. (Thanks to tglx for suggesting this approach!) + */ + t = container_of(tb, struct task_struct, rcu_node_entry); + rt_mutex_init_proxy_locked(&mtx, t); + t->rcu_boost_mutex = &mtx; + t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BOOSTED; + raw_local_irq_restore(flags); + rt_mutex_lock(&mtx); + rt_mutex_unlock(&mtx); /* Keep lockdep happy. */ + + return rcu_preempt_ctrlblk.boost_tasks != NULL || + rcu_preempt_ctrlblk.exp_tasks != NULL; +} + +/* + * Check to see if it is now time to start boosting RCU readers blocking + * the current grace period, and, if so, tell the rcu_kthread_task to + * start boosting them. If there is an expedited boost in progress, + * we wait for it to complete. + * + * If there are no blocked readers blocking the current grace period, + * return 0 to let the caller know, otherwise return 1. Note that this + * return value is independent of whether or not boosting was done. + */ +static int rcu_initiate_boost(void) +{ + if (!rcu_preempt_blocked_readers_cgp() && + rcu_preempt_ctrlblk.exp_tasks == NULL) { + RCU_TRACE(rcu_preempt_ctrlblk.n_balk_exp_gp_tasks++); + return 0; + } + if (rcu_preempt_ctrlblk.exp_tasks != NULL || + (rcu_preempt_ctrlblk.gp_tasks != NULL && + rcu_preempt_ctrlblk.boost_tasks == NULL && + ULONG_CMP_GE(jiffies, rcu_preempt_ctrlblk.boost_time))) { + if (rcu_preempt_ctrlblk.exp_tasks == NULL) + rcu_preempt_ctrlblk.boost_tasks = + rcu_preempt_ctrlblk.gp_tasks; + invoke_rcu_kthread(); + } else + RCU_TRACE(rcu_initiate_boost_trace()); + return 1; +} + +#define RCU_BOOST_DELAY_JIFFIES DIV_ROUND_UP(CONFIG_RCU_BOOST_DELAY * HZ, 1000) + +/* + * Do priority-boost accounting for the start of a new grace period. + */ +static void rcu_preempt_boost_start_gp(void) +{ + rcu_preempt_ctrlblk.boost_time = jiffies + RCU_BOOST_DELAY_JIFFIES; +} + +#else /* #ifdef CONFIG_RCU_BOOST */ + +/* + * If there is no RCU priority boosting, we don't boost. + */ +static int rcu_boost(void) +{ + return 0; +} + +/* + * If there is no RCU priority boosting, we don't initiate boosting, + * but we do indicate whether there are blocked readers blocking the + * current grace period. + */ +static int rcu_initiate_boost(void) +{ + return rcu_preempt_blocked_readers_cgp(); +} + +/* + * If there is no RCU priority boosting, nothing to do at grace-period start. + */ +static void rcu_preempt_boost_start_gp(void) +{ +} + +#endif /* else #ifdef CONFIG_RCU_BOOST */ + +/* * Record a preemptible-RCU quiescent state for the specified CPU. Note * that this just means that the task currently running on the CPU is * in a quiescent state. There might be any number of tasks blocked @@ -148,11 +406,14 @@ static void rcu_preempt_cpu_qs(void) rcu_preempt_ctrlblk.gpcpu = rcu_preempt_ctrlblk.gpnum; current->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS; + /* If there is no GP then there is nothing more to do. */ + if (!rcu_preempt_gp_in_progress()) + return; /* - * If there is no GP, or if blocked readers are still blocking GP, - * then there is nothing more to do. + * Check up on boosting. If there are readers blocking the + * current grace period, leave. */ - if (!rcu_preempt_gp_in_progress() || rcu_preempt_blocked_readers_cgp()) + if (rcu_initiate_boost()) return; /* Advance callbacks. */ @@ -164,9 +425,9 @@ static void rcu_preempt_cpu_qs(void) if (!rcu_preempt_blocked_readers_any()) rcu_preempt_ctrlblk.rcb.donetail = rcu_preempt_ctrlblk.nexttail; - /* If there are done callbacks, make RCU_SOFTIRQ process them. */ + /* If there are done callbacks, cause them to be invoked. */ if (*rcu_preempt_ctrlblk.rcb.donetail != NULL) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_kthread(); } /* @@ -178,12 +439,16 @@ static void rcu_preempt_start_gp(void) /* Official start of GP. */ rcu_preempt_ctrlblk.gpnum++; + RCU_TRACE(rcu_preempt_ctrlblk.n_grace_periods++); /* Any blocked RCU readers block new GP. */ if (rcu_preempt_blocked_readers_any()) rcu_preempt_ctrlblk.gp_tasks = rcu_preempt_ctrlblk.blkd_tasks.next; + /* Set up for RCU priority boosting. */ + rcu_preempt_boost_start_gp(); + /* If there is no running reader, CPU is done with GP. */ if (!rcu_preempt_running_reader()) rcu_preempt_cpu_qs(); @@ -304,15 +569,16 @@ static void rcu_read_unlock_special(struct task_struct *t) */ empty = !rcu_preempt_blocked_readers_cgp(); empty_exp = rcu_preempt_ctrlblk.exp_tasks == NULL; - np = t->rcu_node_entry.next; - if (np == &rcu_preempt_ctrlblk.blkd_tasks) - np = NULL; - list_del(&t->rcu_node_entry); + np = rcu_next_node_entry(t); + list_del_init(&t->rcu_node_entry); if (&t->rcu_node_entry == rcu_preempt_ctrlblk.gp_tasks) rcu_preempt_ctrlblk.gp_tasks = np; if (&t->rcu_node_entry == rcu_preempt_ctrlblk.exp_tasks) rcu_preempt_ctrlblk.exp_tasks = np; - INIT_LIST_HEAD(&t->rcu_node_entry); +#ifdef CONFIG_RCU_BOOST + if (&t->rcu_node_entry == rcu_preempt_ctrlblk.boost_tasks) + rcu_preempt_ctrlblk.boost_tasks = np; +#endif /* #ifdef CONFIG_RCU_BOOST */ /* * If this was the last task on the current list, and if @@ -331,6 +597,14 @@ static void rcu_read_unlock_special(struct task_struct *t) if (!empty_exp && rcu_preempt_ctrlblk.exp_tasks == NULL) rcu_report_exp_done(); } +#ifdef CONFIG_RCU_BOOST + /* Unboost self if was boosted. */ + if (special & RCU_READ_UNLOCK_BOOSTED) { + t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BOOSTED; + rt_mutex_unlock(t->rcu_boost_mutex); + t->rcu_boost_mutex = NULL; + } +#endif /* #ifdef CONFIG_RCU_BOOST */ local_irq_restore(flags); } @@ -374,7 +648,7 @@ static void rcu_preempt_check_callbacks(void) rcu_preempt_cpu_qs(); if (&rcu_preempt_ctrlblk.rcb.rcucblist != rcu_preempt_ctrlblk.rcb.donetail) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_kthread(); if (rcu_preempt_gp_in_progress() && rcu_cpu_blocking_cur_gp() && rcu_preempt_running_reader()) @@ -383,7 +657,7 @@ static void rcu_preempt_check_callbacks(void) /* * TINY_PREEMPT_RCU has an extra callback-list tail pointer to - * update, so this is invoked from __rcu_process_callbacks() to + * update, so this is invoked from rcu_process_callbacks() to * handle that case. Of course, it is invoked for all flavors of * RCU, but RCU callbacks can appear only on one of the lists, and * neither ->nexttail nor ->donetail can possibly be NULL, so there @@ -400,7 +674,7 @@ static void rcu_preempt_remove_callbacks(struct rcu_ctrlblk *rcp) */ static void rcu_preempt_process_callbacks(void) { - __rcu_process_callbacks(&rcu_preempt_ctrlblk.rcb); + rcu_process_callbacks(&rcu_preempt_ctrlblk.rcb); } /* @@ -417,6 +691,7 @@ void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) local_irq_save(flags); *rcu_preempt_ctrlblk.nexttail = head; rcu_preempt_ctrlblk.nexttail = &head->next; + RCU_TRACE(rcu_preempt_ctrlblk.rcb.qlen++); rcu_preempt_start_gp(); /* checks to see if GP needed. */ local_irq_restore(flags); } @@ -528,12 +803,16 @@ void synchronize_rcu_expedited(void) rpcp->exp_tasks = rpcp->blkd_tasks.next; if (rpcp->exp_tasks == &rpcp->blkd_tasks) rpcp->exp_tasks = NULL; - local_irq_restore(flags); /* Wait for tail of ->blkd_tasks list to drain. */ - if (rcu_preempted_readers_exp()) + if (!rcu_preempted_readers_exp()) + local_irq_restore(flags); + else { + rcu_initiate_boost(); + local_irq_restore(flags); wait_event(sync_rcu_preempt_exp_wq, !rcu_preempted_readers_exp()); + } /* Clean up and exit. */ barrier(); /* ensure expedited GP seen before counter increment. */ @@ -567,11 +846,32 @@ void exit_rcu(void) if (t->rcu_read_lock_nesting == 0) return; t->rcu_read_lock_nesting = 1; - rcu_read_unlock(); + __rcu_read_unlock(); } #else /* #ifdef CONFIG_TINY_PREEMPT_RCU */ +#ifdef CONFIG_RCU_TRACE + +/* + * Because preemptible RCU does not exist, it is not necessary to + * dump out its statistics. + */ +static void show_tiny_preempt_stats(struct seq_file *m) +{ +} + +#endif /* #ifdef CONFIG_RCU_TRACE */ + +/* + * Because preemptible RCU does not exist, it is never necessary to + * boost preempted RCU readers. + */ +static int rcu_boost(void) +{ + return 0; +} + /* * Because preemptible RCU does not exist, it never has any callbacks * to check. @@ -599,17 +899,109 @@ static void rcu_preempt_process_callbacks(void) #endif /* #else #ifdef CONFIG_TINY_PREEMPT_RCU */ #ifdef CONFIG_DEBUG_LOCK_ALLOC - #include <linux/kernel_stat.h> /* * During boot, we forgive RCU lockdep issues. After this function is * invoked, we start taking RCU lockdep issues seriously. */ -void rcu_scheduler_starting(void) +void __init rcu_scheduler_starting(void) { WARN_ON(nr_context_switches() > 0); rcu_scheduler_active = 1; } #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ + +#ifdef CONFIG_RCU_BOOST +#define RCU_BOOST_PRIO CONFIG_RCU_BOOST_PRIO +#else /* #ifdef CONFIG_RCU_BOOST */ +#define RCU_BOOST_PRIO 1 +#endif /* #else #ifdef CONFIG_RCU_BOOST */ + +#ifdef CONFIG_RCU_TRACE + +#ifdef CONFIG_RCU_BOOST + +static void rcu_initiate_boost_trace(void) +{ + if (list_empty(&rcu_preempt_ctrlblk.blkd_tasks)) + rcu_preempt_ctrlblk.n_balk_blkd_tasks++; + else if (rcu_preempt_ctrlblk.gp_tasks == NULL && + rcu_preempt_ctrlblk.exp_tasks == NULL) + rcu_preempt_ctrlblk.n_balk_exp_gp_tasks++; + else if (rcu_preempt_ctrlblk.boost_tasks != NULL) + rcu_preempt_ctrlblk.n_balk_boost_tasks++; + else if (!ULONG_CMP_GE(jiffies, rcu_preempt_ctrlblk.boost_time)) + rcu_preempt_ctrlblk.n_balk_notyet++; + else + rcu_preempt_ctrlblk.n_balk_nos++; +} + +#endif /* #ifdef CONFIG_RCU_BOOST */ + +static void rcu_trace_sub_qlen(struct rcu_ctrlblk *rcp, int n) +{ + unsigned long flags; + + raw_local_irq_save(flags); + rcp->qlen -= n; + raw_local_irq_restore(flags); +} + +/* + * Dump statistics for TINY_RCU, such as they are. + */ +static int show_tiny_stats(struct seq_file *m, void *unused) +{ + show_tiny_preempt_stats(m); + seq_printf(m, "rcu_sched: qlen: %ld\n", rcu_sched_ctrlblk.qlen); + seq_printf(m, "rcu_bh: qlen: %ld\n", rcu_bh_ctrlblk.qlen); + return 0; +} + +static int show_tiny_stats_open(struct inode *inode, struct file *file) +{ + return single_open(file, show_tiny_stats, NULL); +} + +static const struct file_operations show_tiny_stats_fops = { + .owner = THIS_MODULE, + .open = show_tiny_stats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static struct dentry *rcudir; + +static int __init rcutiny_trace_init(void) +{ + struct dentry *retval; + + rcudir = debugfs_create_dir("rcu", NULL); + if (!rcudir) + goto free_out; + retval = debugfs_create_file("rcudata", 0444, rcudir, + NULL, &show_tiny_stats_fops); + if (!retval) + goto free_out; + return 0; +free_out: + debugfs_remove_recursive(rcudir); + return 1; +} + +static void __exit rcutiny_trace_cleanup(void) +{ + debugfs_remove_recursive(rcudir); +} + +module_init(rcutiny_trace_init); +module_exit(rcutiny_trace_cleanup); + +MODULE_AUTHOR("Paul E. McKenney"); +MODULE_DESCRIPTION("Read-Copy Update tracing for tiny implementation"); +MODULE_LICENSE("GPL"); + +#endif /* #ifdef CONFIG_RCU_TRACE */ diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 9d8e8fb2515..2e138db0338 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -64,6 +64,9 @@ static int irqreader = 1; /* RCU readers from irq (timers). */ static int fqs_duration = 0; /* Duration of bursts (us), 0 to disable. */ static int fqs_holdoff = 0; /* Hold time within burst (us). */ static int fqs_stutter = 3; /* Wait time between bursts (s). */ +static int test_boost = 1; /* Test RCU prio boost: 0=no, 1=maybe, 2=yes. */ +static int test_boost_interval = 7; /* Interval between boost tests, seconds. */ +static int test_boost_duration = 4; /* Duration of each boost test, seconds. */ static char *torture_type = "rcu"; /* What RCU implementation to torture. */ module_param(nreaders, int, 0444); @@ -88,6 +91,12 @@ module_param(fqs_holdoff, int, 0444); MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)"); module_param(fqs_stutter, int, 0444); MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)"); +module_param(test_boost, int, 0444); +MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); +module_param(test_boost_interval, int, 0444); +MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds."); +module_param(test_boost_duration, int, 0444); +MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds."); module_param(torture_type, charp, 0444); MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); @@ -109,6 +118,7 @@ static struct task_struct *stats_task; static struct task_struct *shuffler_task; static struct task_struct *stutter_task; static struct task_struct *fqs_task; +static struct task_struct *boost_tasks[NR_CPUS]; #define RCU_TORTURE_PIPE_LEN 10 @@ -121,7 +131,7 @@ struct rcu_torture { static LIST_HEAD(rcu_torture_freelist); static struct rcu_torture __rcu *rcu_torture_current; -static long rcu_torture_current_version; +static unsigned long rcu_torture_current_version; static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; static DEFINE_SPINLOCK(rcu_torture_lock); static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = @@ -134,6 +144,10 @@ static atomic_t n_rcu_torture_alloc_fail; static atomic_t n_rcu_torture_free; static atomic_t n_rcu_torture_mberror; static atomic_t n_rcu_torture_error; +static long n_rcu_torture_boost_ktrerror; +static long n_rcu_torture_boost_rterror; +static long n_rcu_torture_boost_failure; +static long n_rcu_torture_boosts; static long n_rcu_torture_timers; static struct list_head rcu_torture_removed; static cpumask_var_t shuffle_tmp_mask; @@ -147,6 +161,16 @@ static int stutter_pause_test; #endif int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT; +#if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) +#define rcu_can_boost() 1 +#else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ +#define rcu_can_boost() 0 +#endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */ + +static unsigned long boost_starttime; /* jiffies of next boost test start. */ +DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */ + /* and boost task create/destroy. */ + /* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */ #define FULLSTOP_DONTSTOP 0 /* Normal operation. */ @@ -277,6 +301,7 @@ struct rcu_torture_ops { void (*fqs)(void); int (*stats)(char *page); int irq_capable; + int can_boost; char *name; }; @@ -366,6 +391,7 @@ static struct rcu_torture_ops rcu_ops = { .fqs = rcu_force_quiescent_state, .stats = NULL, .irq_capable = 1, + .can_boost = rcu_can_boost(), .name = "rcu" }; @@ -408,6 +434,7 @@ static struct rcu_torture_ops rcu_sync_ops = { .fqs = rcu_force_quiescent_state, .stats = NULL, .irq_capable = 1, + .can_boost = rcu_can_boost(), .name = "rcu_sync" }; @@ -424,6 +451,7 @@ static struct rcu_torture_ops rcu_expedited_ops = { .fqs = rcu_force_quiescent_state, .stats = NULL, .irq_capable = 1, + .can_boost = rcu_can_boost(), .name = "rcu_expedited" }; @@ -684,6 +712,112 @@ static struct rcu_torture_ops sched_expedited_ops = { }; /* + * RCU torture priority-boost testing. Runs one real-time thread per + * CPU for moderate bursts, repeatedly registering RCU callbacks and + * spinning waiting for them to be invoked. If a given callback takes + * too long to be invoked, we assume that priority inversion has occurred. + */ + +struct rcu_boost_inflight { + struct rcu_head rcu; + int inflight; +}; + +static void rcu_torture_boost_cb(struct rcu_head *head) +{ + struct rcu_boost_inflight *rbip = + container_of(head, struct rcu_boost_inflight, rcu); + + smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */ + rbip->inflight = 0; +} + +static int rcu_torture_boost(void *arg) +{ + unsigned long call_rcu_time; + unsigned long endtime; + unsigned long oldstarttime; + struct rcu_boost_inflight rbi = { .inflight = 0 }; + struct sched_param sp; + + VERBOSE_PRINTK_STRING("rcu_torture_boost started"); + + /* Set real-time priority. */ + sp.sched_priority = 1; + if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { + VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!"); + n_rcu_torture_boost_rterror++; + } + + init_rcu_head_on_stack(&rbi.rcu); + /* Each pass through the following loop does one boost-test cycle. */ + do { + /* Wait for the next test interval. */ + oldstarttime = boost_starttime; + while (jiffies - oldstarttime > ULONG_MAX / 2) { + schedule_timeout_uninterruptible(1); + rcu_stutter_wait("rcu_torture_boost"); + if (kthread_should_stop() || + fullstop != FULLSTOP_DONTSTOP) + goto checkwait; + } + + /* Do one boost-test interval. */ + endtime = oldstarttime + test_boost_duration * HZ; + call_rcu_time = jiffies; + while (jiffies - endtime > ULONG_MAX / 2) { + /* If we don't have a callback in flight, post one. */ + if (!rbi.inflight) { + smp_mb(); /* RCU core before ->inflight = 1. */ + rbi.inflight = 1; + call_rcu(&rbi.rcu, rcu_torture_boost_cb); + if (jiffies - call_rcu_time > + test_boost_duration * HZ - HZ / 2) { + VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed"); + n_rcu_torture_boost_failure++; + } + call_rcu_time = jiffies; + } + cond_resched(); + rcu_stutter_wait("rcu_torture_boost"); + if (kthread_should_stop() || + fullstop != FULLSTOP_DONTSTOP) + goto checkwait; + } + + /* + * Set the start time of the next test interval. + * Yes, this is vulnerable to long delays, but such + * delays simply cause a false negative for the next + * interval. Besides, we are running at RT priority, + * so delays should be relatively rare. + */ + while (oldstarttime == boost_starttime) { + if (mutex_trylock(&boost_mutex)) { + boost_starttime = jiffies + + test_boost_interval * HZ; + n_rcu_torture_boosts++; + mutex_unlock(&boost_mutex); + break; + } + schedule_timeout_uninterruptible(1); + } + + /* Go do the stutter. */ +checkwait: rcu_stutter_wait("rcu_torture_boost"); + } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); + + /* Clean up and exit. */ + VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping"); + destroy_rcu_head_on_stack(&rbi.rcu); + rcutorture_shutdown_absorb("rcu_torture_boost"); + while (!kthread_should_stop() || rbi.inflight) + schedule_timeout_uninterruptible(1); + smp_mb(); /* order accesses to ->inflight before stack-frame death. */ + return 0; +} + +/* * RCU torture force-quiescent-state kthread. Repeatedly induces * bursts of calls to force_quiescent_state(), increasing the probability * of occurrence of some important types of race conditions. @@ -752,7 +886,7 @@ rcu_torture_writer(void *arg) old_rp->rtort_pipe_count++; cur_ops->deferred_free(old_rp); } - rcu_torture_current_version++; + rcutorture_record_progress(++rcu_torture_current_version); oldbatch = cur_ops->completed(); rcu_stutter_wait("rcu_torture_writer"); } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); @@ -932,8 +1066,9 @@ rcu_torture_printk(char *page) } cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); cnt += sprintf(&page[cnt], - "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " - "rtmbe: %d nt: %ld", + "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d " + "rtmbe: %d rtbke: %ld rtbre: %ld " + "rtbf: %ld rtb: %ld nt: %ld", rcu_torture_current, rcu_torture_current_version, list_empty(&rcu_torture_freelist), @@ -941,8 +1076,15 @@ rcu_torture_printk(char *page) atomic_read(&n_rcu_torture_alloc_fail), atomic_read(&n_rcu_torture_free), atomic_read(&n_rcu_torture_mberror), + n_rcu_torture_boost_ktrerror, + n_rcu_torture_boost_rterror, + n_rcu_torture_boost_failure, + n_rcu_torture_boosts, n_rcu_torture_timers); - if (atomic_read(&n_rcu_torture_mberror) != 0) + if (atomic_read(&n_rcu_torture_mberror) != 0 || + n_rcu_torture_boost_ktrerror != 0 || + n_rcu_torture_boost_rterror != 0 || + n_rcu_torture_boost_failure != 0) cnt += sprintf(&page[cnt], " !!!"); cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); if (i > 1) { @@ -1094,28 +1236,98 @@ rcu_torture_stutter(void *arg) } static inline void -rcu_torture_print_module_parms(char *tag) +rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag) { printk(KERN_ALERT "%s" TORTURE_FLAG "--- %s: nreaders=%d nfakewriters=%d " "stat_interval=%d verbose=%d test_no_idle_hz=%d " "shuffle_interval=%d stutter=%d irqreader=%d " - "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d\n", + "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d " + "test_boost=%d/%d test_boost_interval=%d " + "test_boost_duration=%d\n", torture_type, tag, nrealreaders, nfakewriters, stat_interval, verbose, test_no_idle_hz, shuffle_interval, - stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter); + stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter, + test_boost, cur_ops->can_boost, + test_boost_interval, test_boost_duration); } -static struct notifier_block rcutorture_nb = { +static struct notifier_block rcutorture_shutdown_nb = { .notifier_call = rcutorture_shutdown_notify, }; +static void rcutorture_booster_cleanup(int cpu) +{ + struct task_struct *t; + + if (boost_tasks[cpu] == NULL) + return; + mutex_lock(&boost_mutex); + VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task"); + t = boost_tasks[cpu]; + boost_tasks[cpu] = NULL; + mutex_unlock(&boost_mutex); + + /* This must be outside of the mutex, otherwise deadlock! */ + kthread_stop(t); +} + +static int rcutorture_booster_init(int cpu) +{ + int retval; + + if (boost_tasks[cpu] != NULL) + return 0; /* Already created, nothing more to do. */ + + /* Don't allow time recalculation while creating a new task. */ + mutex_lock(&boost_mutex); + VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task"); + boost_tasks[cpu] = kthread_create(rcu_torture_boost, NULL, + "rcu_torture_boost"); + if (IS_ERR(boost_tasks[cpu])) { + retval = PTR_ERR(boost_tasks[cpu]); + VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed"); + n_rcu_torture_boost_ktrerror++; + boost_tasks[cpu] = NULL; + mutex_unlock(&boost_mutex); + return retval; + } + kthread_bind(boost_tasks[cpu], cpu); + wake_up_process(boost_tasks[cpu]); + mutex_unlock(&boost_mutex); + return 0; +} + +static int rcutorture_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + long cpu = (long)hcpu; + + switch (action) { + case CPU_ONLINE: + case CPU_DOWN_FAILED: + (void)rcutorture_booster_init(cpu); + break; + case CPU_DOWN_PREPARE: + rcutorture_booster_cleanup(cpu); + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block rcutorture_cpu_nb = { + .notifier_call = rcutorture_cpu_notify, +}; + static void rcu_torture_cleanup(void) { int i; mutex_lock(&fullstop_mutex); + rcutorture_record_test_transition(); if (fullstop == FULLSTOP_SHUTDOWN) { printk(KERN_WARNING /* but going down anyway, so... */ "Concurrent 'rmmod rcutorture' and shutdown illegal!\n"); @@ -1127,7 +1339,7 @@ rcu_torture_cleanup(void) } fullstop = FULLSTOP_RMMOD; mutex_unlock(&fullstop_mutex); - unregister_reboot_notifier(&rcutorture_nb); + unregister_reboot_notifier(&rcutorture_shutdown_nb); if (stutter_task) { VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task"); kthread_stop(stutter_task); @@ -1184,6 +1396,12 @@ rcu_torture_cleanup(void) kthread_stop(fqs_task); } fqs_task = NULL; + if ((test_boost == 1 && cur_ops->can_boost) || + test_boost == 2) { + unregister_cpu_notifier(&rcutorture_cpu_nb); + for_each_possible_cpu(i) + rcutorture_booster_cleanup(i); + } /* Wait for all RCU callbacks to fire. */ @@ -1195,9 +1413,9 @@ rcu_torture_cleanup(void) if (cur_ops->cleanup) cur_ops->cleanup(); if (atomic_read(&n_rcu_torture_error)) - rcu_torture_print_module_parms("End of test: FAILURE"); + rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE"); else - rcu_torture_print_module_parms("End of test: SUCCESS"); + rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); } static int __init @@ -1242,7 +1460,7 @@ rcu_torture_init(void) nrealreaders = nreaders; else nrealreaders = 2 * num_online_cpus(); - rcu_torture_print_module_parms("Start of test"); + rcu_torture_print_module_parms(cur_ops, "Start of test"); fullstop = FULLSTOP_DONTSTOP; /* Set up the freelist. */ @@ -1263,6 +1481,10 @@ rcu_torture_init(void) atomic_set(&n_rcu_torture_free, 0); atomic_set(&n_rcu_torture_mberror, 0); atomic_set(&n_rcu_torture_error, 0); + n_rcu_torture_boost_ktrerror = 0; + n_rcu_torture_boost_rterror = 0; + n_rcu_torture_boost_failure = 0; + n_rcu_torture_boosts = 0; for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) atomic_set(&rcu_torture_wcount[i], 0); for_each_possible_cpu(cpu) { @@ -1376,7 +1598,28 @@ rcu_torture_init(void) goto unwind; } } - register_reboot_notifier(&rcutorture_nb); + if (test_boost_interval < 1) + test_boost_interval = 1; + if (test_boost_duration < 2) + test_boost_duration = 2; + if ((test_boost == 1 && cur_ops->can_boost) || + test_boost == 2) { + int retval; + + boost_starttime = jiffies + test_boost_interval * HZ; + register_cpu_notifier(&rcutorture_cpu_nb); + for_each_possible_cpu(i) { + if (cpu_is_offline(i)) + continue; /* Heuristic: CPU can go offline. */ + retval = rcutorture_booster_init(i); + if (retval < 0) { + firsterr = retval; + goto unwind; + } + } + } + register_reboot_notifier(&rcutorture_shutdown_nb); + rcutorture_record_test_transition(); mutex_unlock(&fullstop_mutex); return 0; diff --git a/kernel/rcutree.c b/kernel/rcutree.c index ccdc04c4798..e486f7c3ffb 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -47,6 +47,8 @@ #include <linux/mutex.h> #include <linux/time.h> #include <linux/kernel_stat.h> +#include <linux/wait.h> +#include <linux/kthread.h> #include "rcutree.h" @@ -67,9 +69,6 @@ static struct lock_class_key rcu_node_class[NUM_RCU_LVLS]; .gpnum = -300, \ .completed = -300, \ .onofflock = __RAW_SPIN_LOCK_UNLOCKED(&structname.onofflock), \ - .orphan_cbs_list = NULL, \ - .orphan_cbs_tail = &structname.orphan_cbs_list, \ - .orphan_qlen = 0, \ .fqslock = __RAW_SPIN_LOCK_UNLOCKED(&structname.fqslock), \ .n_force_qs = 0, \ .n_force_qs_ngp = 0, \ @@ -82,10 +81,41 @@ DEFINE_PER_CPU(struct rcu_data, rcu_sched_data); struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state); DEFINE_PER_CPU(struct rcu_data, rcu_bh_data); +static struct rcu_state *rcu_state; + int rcu_scheduler_active __read_mostly; EXPORT_SYMBOL_GPL(rcu_scheduler_active); /* + * Control variables for per-CPU and per-rcu_node kthreads. These + * handle all flavors of RCU. + */ +static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task); +DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status); +DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu); +DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); +static DEFINE_PER_CPU(wait_queue_head_t, rcu_cpu_wq); +DEFINE_PER_CPU(char, rcu_cpu_has_work); +static char rcu_kthreads_spawnable; + +static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu); +static void invoke_rcu_cpu_kthread(void); + +#define RCU_KTHREAD_PRIO 1 /* RT priority for per-CPU kthreads. */ + +/* + * Track the rcutorture test sequence number and the update version + * number within a given test. The rcutorture_testseq is incremented + * on every rcutorture module load and unload, so has an odd value + * when a test is running. The rcutorture_vernum is set to zero + * when rcutorture starts and is incremented on each rcutorture update. + * These variables enable correlating rcutorture output with the + * RCU tracing information. + */ +unsigned long rcutorture_testseq; +unsigned long rcutorture_vernum; + +/* * Return true if an RCU grace period is in progress. The ACCESS_ONCE()s * permit this function to be invoked without holding the root rcu_node * structure's ->lock, but of course results can be subject to change. @@ -127,6 +157,7 @@ void rcu_note_context_switch(int cpu) rcu_sched_qs(cpu); rcu_preempt_note_context_switch(cpu); } +EXPORT_SYMBOL_GPL(rcu_note_context_switch); #ifdef CONFIG_NO_HZ DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { @@ -143,10 +174,8 @@ module_param(blimit, int, 0); module_param(qhimark, int, 0); module_param(qlowmark, int, 0); -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR -int rcu_cpu_stall_suppress __read_mostly = RCU_CPU_STALL_SUPPRESS_INIT; +int rcu_cpu_stall_suppress __read_mostly; module_param(rcu_cpu_stall_suppress, int, 0644); -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ static void force_quiescent_state(struct rcu_state *rsp, int relaxed); static int rcu_pending(int cpu); @@ -179,6 +208,31 @@ void rcu_bh_force_quiescent_state(void) EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state); /* + * Record the number of times rcutorture tests have been initiated and + * terminated. This information allows the debugfs tracing stats to be + * correlated to the rcutorture messages, even when the rcutorture module + * is being repeatedly loaded and unloaded. In other words, we cannot + * store this state in rcutorture itself. + */ +void rcutorture_record_test_transition(void) +{ + rcutorture_testseq++; + rcutorture_vernum = 0; +} +EXPORT_SYMBOL_GPL(rcutorture_record_test_transition); + +/* + * Record the number of writer passes through the current rcutorture test. + * This is also used to correlate debugfs tracing stats with the rcutorture + * messages. + */ +void rcutorture_record_progress(unsigned long vernum) +{ + rcutorture_vernum++; +} +EXPORT_SYMBOL_GPL(rcutorture_record_progress); + +/* * Force a quiescent state for RCU-sched. */ void rcu_sched_force_quiescent_state(void) @@ -237,8 +291,8 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp) return 1; } - /* If preemptable RCU, no point in sending reschedule IPI. */ - if (rdp->preemptable) + /* If preemptible RCU, no point in sending reschedule IPI. */ + if (rdp->preemptible) return 0; /* The CPU is online, so send it a reschedule IPI. */ @@ -367,8 +421,8 @@ void rcu_irq_exit(void) WARN_ON_ONCE(rdtp->dynticks & 0x1); /* If the interrupt queued a callback, get out of dyntick mode. */ - if (__get_cpu_var(rcu_sched_data).nxtlist || - __get_cpu_var(rcu_bh_data).nxtlist) + if (__this_cpu_read(rcu_sched_data.nxtlist) || + __this_cpu_read(rcu_bh_data.nxtlist)) set_need_resched(); } @@ -453,8 +507,6 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) #endif /* #else #ifdef CONFIG_NO_HZ */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR - int rcu_cpu_stall_suppress __read_mostly; static void record_gp_stall_check_time(struct rcu_state *rsp) @@ -540,21 +592,24 @@ static void print_cpu_stall(struct rcu_state *rsp) static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp) { - long delta; + unsigned long j; + unsigned long js; struct rcu_node *rnp; if (rcu_cpu_stall_suppress) return; - delta = jiffies - ACCESS_ONCE(rsp->jiffies_stall); + j = ACCESS_ONCE(jiffies); + js = ACCESS_ONCE(rsp->jiffies_stall); rnp = rdp->mynode; - if ((ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && delta >= 0) { + if ((ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && ULONG_CMP_GE(j, js)) { /* We haven't checked in, so go dump stack. */ print_cpu_stall(rsp); - } else if (rcu_gp_in_progress(rsp) && delta >= RCU_STALL_RAT_DELAY) { + } else if (rcu_gp_in_progress(rsp) && + ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY)) { - /* They had two time units to dump stack, so complain. */ + /* They had a few time units to dump stack, so complain. */ print_other_cpu_stall(rsp); } } @@ -590,26 +645,6 @@ static void __init check_cpu_stall_init(void) atomic_notifier_chain_register(&panic_notifier_list, &rcu_panic_block); } -#else /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ - -static void record_gp_stall_check_time(struct rcu_state *rsp) -{ -} - -static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp) -{ -} - -void rcu_cpu_stall_reset(void) -{ -} - -static void __init check_cpu_stall_init(void) -{ -} - -#endif /* #else #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ - /* * Update CPU-local rcu_data state to record the newly noticed grace period. * This is used both when we started the grace period and when we notice @@ -620,9 +655,17 @@ static void __init check_cpu_stall_init(void) static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp) { if (rdp->gpnum != rnp->gpnum) { - rdp->qs_pending = 1; - rdp->passed_quiesc = 0; + /* + * If the current grace period is waiting for this CPU, + * set up to detect a quiescent state, otherwise don't + * go looking for one. + */ rdp->gpnum = rnp->gpnum; + if (rnp->qsmask & rdp->grpmask) { + rdp->qs_pending = 1; + rdp->passed_quiesc = 0; + } else + rdp->qs_pending = 0; } } @@ -681,6 +724,24 @@ __rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_dat /* Remember that we saw this grace-period completion. */ rdp->completed = rnp->completed; + + /* + * If we were in an extended quiescent state, we may have + * missed some grace periods that others CPUs handled on + * our behalf. Catch up with this state to avoid noting + * spurious new grace periods. If another grace period + * has started, then rnp->gpnum will have advanced, so + * we will detect this later on. + */ + if (ULONG_CMP_LT(rdp->gpnum, rdp->completed)) + rdp->gpnum = rdp->completed; + + /* + * If RCU does not need a quiescent state from this CPU, + * then make sure that this CPU doesn't go looking for one. + */ + if ((rnp->qsmask & rdp->grpmask) == 0) + rdp->qs_pending = 0; } } @@ -786,6 +847,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) rnp->completed = rsp->completed; rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */ rcu_start_gp_per_cpu(rsp, rnp, rdp); + rcu_preempt_boost_start_gp(rnp); raw_spin_unlock_irqrestore(&rnp->lock, flags); return; } @@ -821,6 +883,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) rnp->completed = rsp->completed; if (rnp == rdp->mynode) rcu_start_gp_per_cpu(rsp, rnp, rdp); + rcu_preempt_boost_start_gp(rnp); raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ } @@ -841,7 +904,12 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) __releases(rcu_get_root(rsp)->lock) { + unsigned long gp_duration; + WARN_ON_ONCE(!rcu_gp_in_progress(rsp)); + gp_duration = jiffies - rsp->gp_start; + if (gp_duration > rsp->gp_max) + rsp->gp_max = gp_duration; rsp->completed = rsp->gpnum; rsp->signaled = RCU_GP_IDLE; rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */ @@ -871,7 +939,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, return; } rnp->qsmask &= ~mask; - if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) { + if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { /* Other bits still set at this level, so done. */ raw_spin_unlock_irqrestore(&rnp->lock, flags); @@ -984,58 +1052,38 @@ rcu_check_quiescent_state(struct rcu_state *rsp, struct rcu_data *rdp) #ifdef CONFIG_HOTPLUG_CPU /* - * Move a dying CPU's RCU callbacks to the ->orphan_cbs_list for the - * specified flavor of RCU. The callbacks will be adopted by the next - * _rcu_barrier() invocation or by the CPU_DEAD notifier, whichever - * comes first. Because this is invoked from the CPU_DYING notifier, - * irqs are already disabled. + * Move a dying CPU's RCU callbacks to online CPU's callback list. + * Synchronization is not required because this function executes + * in stop_machine() context. */ -static void rcu_send_cbs_to_orphanage(struct rcu_state *rsp) +static void rcu_send_cbs_to_online(struct rcu_state *rsp) { int i; + /* current DYING CPU is cleared in the cpu_online_mask */ + int receive_cpu = cpumask_any(cpu_online_mask); struct rcu_data *rdp = this_cpu_ptr(rsp->rda); + struct rcu_data *receive_rdp = per_cpu_ptr(rsp->rda, receive_cpu); if (rdp->nxtlist == NULL) return; /* irqs disabled, so comparison is stable. */ - raw_spin_lock(&rsp->onofflock); /* irqs already disabled. */ - *rsp->orphan_cbs_tail = rdp->nxtlist; - rsp->orphan_cbs_tail = rdp->nxttail[RCU_NEXT_TAIL]; + + *receive_rdp->nxttail[RCU_NEXT_TAIL] = rdp->nxtlist; + receive_rdp->nxttail[RCU_NEXT_TAIL] = rdp->nxttail[RCU_NEXT_TAIL]; + receive_rdp->qlen += rdp->qlen; + receive_rdp->n_cbs_adopted += rdp->qlen; + rdp->n_cbs_orphaned += rdp->qlen; + rdp->nxtlist = NULL; for (i = 0; i < RCU_NEXT_SIZE; i++) rdp->nxttail[i] = &rdp->nxtlist; - rsp->orphan_qlen += rdp->qlen; - rdp->n_cbs_orphaned += rdp->qlen; rdp->qlen = 0; - raw_spin_unlock(&rsp->onofflock); /* irqs remain disabled. */ -} - -/* - * Adopt previously orphaned RCU callbacks. - */ -static void rcu_adopt_orphan_cbs(struct rcu_state *rsp) -{ - unsigned long flags; - struct rcu_data *rdp; - - raw_spin_lock_irqsave(&rsp->onofflock, flags); - rdp = this_cpu_ptr(rsp->rda); - if (rsp->orphan_cbs_list == NULL) { - raw_spin_unlock_irqrestore(&rsp->onofflock, flags); - return; - } - *rdp->nxttail[RCU_NEXT_TAIL] = rsp->orphan_cbs_list; - rdp->nxttail[RCU_NEXT_TAIL] = rsp->orphan_cbs_tail; - rdp->qlen += rsp->orphan_qlen; - rdp->n_cbs_adopted += rsp->orphan_qlen; - rsp->orphan_cbs_list = NULL; - rsp->orphan_cbs_tail = &rsp->orphan_cbs_list; - rsp->orphan_qlen = 0; - raw_spin_unlock_irqrestore(&rsp->onofflock, flags); } /* * Remove the outgoing CPU from the bitmasks in the rcu_node hierarchy * and move all callbacks from the outgoing CPU to the current one. + * There can only be one CPU hotplug operation at a time, so no other + * CPU can be attempting to update rcu_cpu_kthread_task. */ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) { @@ -1044,6 +1092,14 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) int need_report = 0; struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu); struct rcu_node *rnp; + struct task_struct *t; + + /* Stop the CPU's kthread. */ + t = per_cpu(rcu_cpu_kthread_task, cpu); + if (t != NULL) { + per_cpu(rcu_cpu_kthread_task, cpu) = NULL; + kthread_stop(t); + } /* Exclude any attempts to start a new grace period. */ raw_spin_lock_irqsave(&rsp->onofflock, flags); @@ -1081,8 +1137,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) raw_spin_unlock_irqrestore(&rnp->lock, flags); if (need_report & RCU_OFL_TASKS_EXP_GP) rcu_report_exp_rnp(rsp, rnp); - - rcu_adopt_orphan_cbs(rsp); + rcu_node_kthread_setaffinity(rnp, -1); } /* @@ -1100,11 +1155,7 @@ static void rcu_offline_cpu(int cpu) #else /* #ifdef CONFIG_HOTPLUG_CPU */ -static void rcu_send_cbs_to_orphanage(struct rcu_state *rsp) -{ -} - -static void rcu_adopt_orphan_cbs(struct rcu_state *rsp) +static void rcu_send_cbs_to_online(struct rcu_state *rsp) { } @@ -1148,7 +1199,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) next = list->next; prefetch(next); debug_rcu_head_unqueue(list); - list->func(list); + __rcu_reclaim(list); list = next; if (++count >= rdp->blimit) break; @@ -1184,7 +1235,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) /* Re-raise the RCU softirq if there are callbacks remaining. */ if (cpu_has_callbacks_ready_to_invoke(rdp)) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_cpu_kthread(); } /* @@ -1230,7 +1281,7 @@ void rcu_check_callbacks(int cpu, int user) } rcu_preempt_check_callbacks(cpu); if (rcu_pending(cpu)) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_cpu_kthread(); } #ifdef CONFIG_SMP @@ -1238,6 +1289,8 @@ void rcu_check_callbacks(int cpu, int user) /* * Scan the leaf rcu_node structures, processing dyntick state for any that * have not yet encountered a quiescent state, using the function specified. + * Also initiate boosting for any threads blocked on the root rcu_node. + * * The caller must have suppressed start of new grace periods. */ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *)) @@ -1256,7 +1309,7 @@ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *)) return; } if (rnp->qsmask == 0) { - raw_spin_unlock_irqrestore(&rnp->lock, flags); + rcu_initiate_boost(rnp, flags); /* releases rnp->lock */ continue; } cpu = rnp->grplo; @@ -1274,6 +1327,11 @@ static void force_qs_rnp(struct rcu_state *rsp, int (*f)(struct rcu_data *)) } raw_spin_unlock_irqrestore(&rnp->lock, flags); } + rnp = rcu_get_root(rsp); + if (rnp->qsmask == 0) { + raw_spin_lock_irqsave(&rnp->lock, flags); + rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */ + } } /* @@ -1394,7 +1452,7 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp) /* * Do softirq processing for the current CPU. */ -static void rcu_process_callbacks(struct softirq_action *unused) +static void rcu_process_callbacks(void) { /* * Memory references from any prior RCU read-side critical sections @@ -1419,6 +1477,347 @@ static void rcu_process_callbacks(struct softirq_action *unused) rcu_needs_cpu_flush(); } +/* + * Wake up the current CPU's kthread. This replaces raise_softirq() + * in earlier versions of RCU. Note that because we are running on + * the current CPU with interrupts disabled, the rcu_cpu_kthread_task + * cannot disappear out from under us. + */ +static void invoke_rcu_cpu_kthread(void) +{ + unsigned long flags; + + local_irq_save(flags); + __this_cpu_write(rcu_cpu_has_work, 1); + if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) { + local_irq_restore(flags); + return; + } + wake_up(&__get_cpu_var(rcu_cpu_wq)); + local_irq_restore(flags); +} + +/* + * Wake up the specified per-rcu_node-structure kthread. + * Because the per-rcu_node kthreads are immortal, we don't need + * to do anything to keep them alive. + */ +static void invoke_rcu_node_kthread(struct rcu_node *rnp) +{ + struct task_struct *t; + + t = rnp->node_kthread_task; + if (t != NULL) + wake_up_process(t); +} + +/* + * Set the specified CPU's kthread to run RT or not, as specified by + * the to_rt argument. The CPU-hotplug locks are held, so the task + * is not going away. + */ +static void rcu_cpu_kthread_setrt(int cpu, int to_rt) +{ + int policy; + struct sched_param sp; + struct task_struct *t; + + t = per_cpu(rcu_cpu_kthread_task, cpu); + if (t == NULL) + return; + if (to_rt) { + policy = SCHED_FIFO; + sp.sched_priority = RCU_KTHREAD_PRIO; + } else { + policy = SCHED_NORMAL; + sp.sched_priority = 0; + } + sched_setscheduler_nocheck(t, policy, &sp); +} + +/* + * Timer handler to initiate the waking up of per-CPU kthreads that + * have yielded the CPU due to excess numbers of RCU callbacks. + * We wake up the per-rcu_node kthread, which in turn will wake up + * the booster kthread. + */ +static void rcu_cpu_kthread_timer(unsigned long arg) +{ + unsigned long flags; + struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, arg); + struct rcu_node *rnp = rdp->mynode; + + raw_spin_lock_irqsave(&rnp->lock, flags); + rnp->wakemask |= rdp->grpmask; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + invoke_rcu_node_kthread(rnp); +} + +/* + * Drop to non-real-time priority and yield, but only after posting a + * timer that will cause us to regain our real-time priority if we + * remain preempted. Either way, we restore our real-time priority + * before returning. + */ +static void rcu_yield(void (*f)(unsigned long), unsigned long arg) +{ + struct sched_param sp; + struct timer_list yield_timer; + + setup_timer_on_stack(&yield_timer, f, arg); + mod_timer(&yield_timer, jiffies + 2); + sp.sched_priority = 0; + sched_setscheduler_nocheck(current, SCHED_NORMAL, &sp); + set_user_nice(current, 19); + schedule(); + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); + del_timer(&yield_timer); +} + +/* + * Handle cases where the rcu_cpu_kthread() ends up on the wrong CPU. + * This can happen while the corresponding CPU is either coming online + * or going offline. We cannot wait until the CPU is fully online + * before starting the kthread, because the various notifier functions + * can wait for RCU grace periods. So we park rcu_cpu_kthread() until + * the corresponding CPU is online. + * + * Return 1 if the kthread needs to stop, 0 otherwise. + * + * Caller must disable bh. This function can momentarily enable it. + */ +static int rcu_cpu_kthread_should_stop(int cpu) +{ + while (cpu_is_offline(cpu) || + !cpumask_equal(¤t->cpus_allowed, cpumask_of(cpu)) || + smp_processor_id() != cpu) { + if (kthread_should_stop()) + return 1; + per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU; + per_cpu(rcu_cpu_kthread_cpu, cpu) = raw_smp_processor_id(); + local_bh_enable(); + schedule_timeout_uninterruptible(1); + if (!cpumask_equal(¤t->cpus_allowed, cpumask_of(cpu))) + set_cpus_allowed_ptr(current, cpumask_of(cpu)); + local_bh_disable(); + } + per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu; + return 0; +} + +/* + * Per-CPU kernel thread that invokes RCU callbacks. This replaces the + * earlier RCU softirq. + */ +static int rcu_cpu_kthread(void *arg) +{ + int cpu = (int)(long)arg; + unsigned long flags; + int spincnt = 0; + unsigned int *statusp = &per_cpu(rcu_cpu_kthread_status, cpu); + wait_queue_head_t *wqp = &per_cpu(rcu_cpu_wq, cpu); + char work; + char *workp = &per_cpu(rcu_cpu_has_work, cpu); + + for (;;) { + *statusp = RCU_KTHREAD_WAITING; + wait_event_interruptible(*wqp, + *workp != 0 || kthread_should_stop()); + local_bh_disable(); + if (rcu_cpu_kthread_should_stop(cpu)) { + local_bh_enable(); + break; + } + *statusp = RCU_KTHREAD_RUNNING; + per_cpu(rcu_cpu_kthread_loops, cpu)++; + local_irq_save(flags); + work = *workp; + *workp = 0; + local_irq_restore(flags); + if (work) + rcu_process_callbacks(); + local_bh_enable(); + if (*workp != 0) + spincnt++; + else + spincnt = 0; + if (spincnt > 10) { + *statusp = RCU_KTHREAD_YIELDING; + rcu_yield(rcu_cpu_kthread_timer, (unsigned long)cpu); + spincnt = 0; + } + } + *statusp = RCU_KTHREAD_STOPPED; + return 0; +} + +/* + * Spawn a per-CPU kthread, setting up affinity and priority. + * Because the CPU hotplug lock is held, no other CPU will be attempting + * to manipulate rcu_cpu_kthread_task. There might be another CPU + * attempting to access it during boot, but the locking in kthread_bind() + * will enforce sufficient ordering. + */ +static int __cpuinit rcu_spawn_one_cpu_kthread(int cpu) +{ + struct sched_param sp; + struct task_struct *t; + + if (!rcu_kthreads_spawnable || + per_cpu(rcu_cpu_kthread_task, cpu) != NULL) + return 0; + t = kthread_create(rcu_cpu_kthread, (void *)(long)cpu, "rcuc%d", cpu); + if (IS_ERR(t)) + return PTR_ERR(t); + kthread_bind(t, cpu); + per_cpu(rcu_cpu_kthread_cpu, cpu) = cpu; + WARN_ON_ONCE(per_cpu(rcu_cpu_kthread_task, cpu) != NULL); + per_cpu(rcu_cpu_kthread_task, cpu) = t; + wake_up_process(t); + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); + return 0; +} + +/* + * Per-rcu_node kthread, which is in charge of waking up the per-CPU + * kthreads when needed. We ignore requests to wake up kthreads + * for offline CPUs, which is OK because force_quiescent_state() + * takes care of this case. + */ +static int rcu_node_kthread(void *arg) +{ + int cpu; + unsigned long flags; + unsigned long mask; + struct rcu_node *rnp = (struct rcu_node *)arg; + struct sched_param sp; + struct task_struct *t; + + for (;;) { + rnp->node_kthread_status = RCU_KTHREAD_WAITING; + wait_event_interruptible(rnp->node_wq, rnp->wakemask != 0); + rnp->node_kthread_status = RCU_KTHREAD_RUNNING; + raw_spin_lock_irqsave(&rnp->lock, flags); + mask = rnp->wakemask; + rnp->wakemask = 0; + rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */ + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) { + if ((mask & 0x1) == 0) + continue; + preempt_disable(); + t = per_cpu(rcu_cpu_kthread_task, cpu); + if (!cpu_online(cpu) || t == NULL) { + preempt_enable(); + continue; + } + per_cpu(rcu_cpu_has_work, cpu) = 1; + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); + preempt_enable(); + } + } + /* NOTREACHED */ + rnp->node_kthread_status = RCU_KTHREAD_STOPPED; + return 0; +} + +/* + * Set the per-rcu_node kthread's affinity to cover all CPUs that are + * served by the rcu_node in question. The CPU hotplug lock is still + * held, so the value of rnp->qsmaskinit will be stable. + * + * We don't include outgoingcpu in the affinity set, use -1 if there is + * no outgoing CPU. If there are no CPUs left in the affinity set, + * this function allows the kthread to execute on any CPU. + */ +static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu) +{ + cpumask_var_t cm; + int cpu; + unsigned long mask = rnp->qsmaskinit; + + if (rnp->node_kthread_task == NULL) + return; + if (!alloc_cpumask_var(&cm, GFP_KERNEL)) + return; + cpumask_clear(cm); + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask >>= 1) + if ((mask & 0x1) && cpu != outgoingcpu) + cpumask_set_cpu(cpu, cm); + if (cpumask_weight(cm) == 0) { + cpumask_setall(cm); + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++) + cpumask_clear_cpu(cpu, cm); + WARN_ON_ONCE(cpumask_weight(cm) == 0); + } + set_cpus_allowed_ptr(rnp->node_kthread_task, cm); + rcu_boost_kthread_setaffinity(rnp, cm); + free_cpumask_var(cm); +} + +/* + * Spawn a per-rcu_node kthread, setting priority and affinity. + * Called during boot before online/offline can happen, or, if + * during runtime, with the main CPU-hotplug locks held. So only + * one of these can be executing at a time. + */ +static int __cpuinit rcu_spawn_one_node_kthread(struct rcu_state *rsp, + struct rcu_node *rnp) +{ + unsigned long flags; + int rnp_index = rnp - &rsp->node[0]; + struct sched_param sp; + struct task_struct *t; + + if (!rcu_kthreads_spawnable || + rnp->qsmaskinit == 0) + return 0; + if (rnp->node_kthread_task == NULL) { + t = kthread_create(rcu_node_kthread, (void *)rnp, + "rcun%d", rnp_index); + if (IS_ERR(t)) + return PTR_ERR(t); + raw_spin_lock_irqsave(&rnp->lock, flags); + rnp->node_kthread_task = t; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + wake_up_process(t); + sp.sched_priority = 99; + sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); + } + return rcu_spawn_one_boost_kthread(rsp, rnp, rnp_index); +} + +/* + * Spawn all kthreads -- called as soon as the scheduler is running. + */ +static int __init rcu_spawn_kthreads(void) +{ + int cpu; + struct rcu_node *rnp; + + rcu_kthreads_spawnable = 1; + for_each_possible_cpu(cpu) { + init_waitqueue_head(&per_cpu(rcu_cpu_wq, cpu)); + per_cpu(rcu_cpu_has_work, cpu) = 0; + if (cpu_online(cpu)) + (void)rcu_spawn_one_cpu_kthread(cpu); + } + rnp = rcu_get_root(rcu_state); + init_waitqueue_head(&rnp->node_wq); + rcu_init_boost_waitqueue(rnp); + (void)rcu_spawn_one_node_kthread(rcu_state, rnp); + if (NUM_RCU_NODES > 1) + rcu_for_each_leaf_node(rcu_state, rnp) { + init_waitqueue_head(&rnp->node_wq); + rcu_init_boost_waitqueue(rnp); + (void)rcu_spawn_one_node_kthread(rcu_state, rnp); + } + return 0; +} +early_initcall(rcu_spawn_kthreads); + static void __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), struct rcu_state *rsp) @@ -1440,20 +1839,16 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), */ local_irq_save(flags); rdp = this_cpu_ptr(rsp->rda); - rcu_process_gp_end(rsp, rdp); - check_for_new_grace_period(rsp, rdp); /* Add the callback to our list. */ *rdp->nxttail[RCU_NEXT_TAIL] = head; rdp->nxttail[RCU_NEXT_TAIL] = &head->next; + rdp->qlen++; - /* Start a new grace period if one not already started. */ - if (!rcu_gp_in_progress(rsp)) { - unsigned long nestflag; - struct rcu_node *rnp_root = rcu_get_root(rsp); - - raw_spin_lock_irqsave(&rnp_root->lock, nestflag); - rcu_start_gp(rsp, nestflag); /* releases rnp_root->lock. */ + /* If interrupts were disabled, don't dive into RCU core. */ + if (irqs_disabled_flags(flags)) { + local_irq_restore(flags); + return; } /* @@ -1463,13 +1858,28 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), * invoking force_quiescent_state() if the newly enqueued callback * is the only one waiting for a grace period to complete. */ - if (unlikely(++rdp->qlen > rdp->qlen_last_fqs_check + qhimark)) { - rdp->blimit = LONG_MAX; - if (rsp->n_force_qs == rdp->n_force_qs_snap && - *rdp->nxttail[RCU_DONE_TAIL] != head) - force_quiescent_state(rsp, 0); - rdp->n_force_qs_snap = rsp->n_force_qs; - rdp->qlen_last_fqs_check = rdp->qlen; + if (unlikely(rdp->qlen > rdp->qlen_last_fqs_check + qhimark)) { + + /* Are we ignoring a completed grace period? */ + rcu_process_gp_end(rsp, rdp); + check_for_new_grace_period(rsp, rdp); + + /* Start a new grace period if one not already started. */ + if (!rcu_gp_in_progress(rsp)) { + unsigned long nestflag; + struct rcu_node *rnp_root = rcu_get_root(rsp); + + raw_spin_lock_irqsave(&rnp_root->lock, nestflag); + rcu_start_gp(rsp, nestflag); /* rlses rnp_root->lock */ + } else { + /* Give the grace period a kick. */ + rdp->blimit = LONG_MAX; + if (rsp->n_force_qs == rdp->n_force_qs_snap && + *rdp->nxttail[RCU_DONE_TAIL] != head) + force_quiescent_state(rsp, 0); + rdp->n_force_qs_snap = rsp->n_force_qs; + rdp->qlen_last_fqs_check = rdp->qlen; + } } else if (ULONG_CMP_LT(ACCESS_ONCE(rsp->jiffies_force_qs), jiffies)) force_quiescent_state(rsp, 1); local_irq_restore(flags); @@ -1584,7 +1994,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp) * or RCU-bh, force a local reschedule. */ rdp->n_rp_qs_pending++; - if (!rdp->preemptable && + if (!rdp->preemptible && ULONG_CMP_LT(ACCESS_ONCE(rsp->jiffies_force_qs) - 1, jiffies)) set_need_resched(); @@ -1699,13 +2109,12 @@ static void _rcu_barrier(struct rcu_state *rsp, * decrement rcu_barrier_cpu_count -- otherwise the first CPU * might complete its grace period before all of the other CPUs * did their increment, causing this function to return too - * early. + * early. Note that on_each_cpu() disables irqs, which prevents + * any CPUs from coming online or going offline until each online + * CPU has queued its RCU-barrier callback. */ atomic_set(&rcu_barrier_cpu_count, 1); - preempt_disable(); /* stop CPU_DYING from filling orphan_cbs_list */ - rcu_adopt_orphan_cbs(rsp); on_each_cpu(rcu_barrier_func, (void *)call_rcu_func, 1); - preempt_enable(); /* CPU_DYING can again fill orphan_cbs_list */ if (atomic_dec_and_test(&rcu_barrier_cpu_count)) complete(&rcu_barrier_completion); wait_for_completion(&rcu_barrier_completion); @@ -1762,7 +2171,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) * that this CPU cannot possibly have any RCU callbacks in flight yet. */ static void __cpuinit -rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable) +rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible) { unsigned long flags; unsigned long mask; @@ -1774,7 +2183,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable) rdp->passed_quiesc = 0; /* We could be racing with new GP, */ rdp->qs_pending = 1; /* so set up to respond to current GP. */ rdp->beenonline = 1; /* We have now been online. */ - rdp->preemptable = preemptable; + rdp->preemptible = preemptible; rdp->qlen_last_fqs_check = 0; rdp->n_force_qs_snap = rsp->n_force_qs; rdp->blimit = blimit; @@ -1815,6 +2224,19 @@ static void __cpuinit rcu_online_cpu(int cpu) rcu_preempt_init_percpu_data(cpu); } +static void __cpuinit rcu_online_kthreads(int cpu) +{ + struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu); + struct rcu_node *rnp = rdp->mynode; + + /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */ + if (rcu_kthreads_spawnable) { + (void)rcu_spawn_one_cpu_kthread(cpu); + if (rnp->node_kthread_task == NULL) + (void)rcu_spawn_one_node_kthread(rcu_state, rnp); + } +} + /* * Handle CPU online/offline notification events. */ @@ -1822,27 +2244,34 @@ static int __cpuinit rcu_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { long cpu = (long)hcpu; + struct rcu_data *rdp = per_cpu_ptr(rcu_state->rda, cpu); + struct rcu_node *rnp = rdp->mynode; switch (action) { case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: rcu_online_cpu(cpu); + rcu_online_kthreads(cpu); + break; + case CPU_ONLINE: + case CPU_DOWN_FAILED: + rcu_node_kthread_setaffinity(rnp, -1); + rcu_cpu_kthread_setrt(cpu, 1); + break; + case CPU_DOWN_PREPARE: + rcu_node_kthread_setaffinity(rnp, cpu); + rcu_cpu_kthread_setrt(cpu, 0); break; case CPU_DYING: case CPU_DYING_FROZEN: /* - * preempt_disable() in _rcu_barrier() prevents stop_machine(), - * so when "on_each_cpu(rcu_barrier_func, (void *)type, 1);" - * returns, all online cpus have queued rcu_barrier_func(). - * The dying CPU clears its cpu_online_mask bit and - * moves all of its RCU callbacks to ->orphan_cbs_list - * in the context of stop_machine(), so subsequent calls - * to _rcu_barrier() will adopt these callbacks and only - * then queue rcu_barrier_func() on all remaining CPUs. + * The whole machine is "stopped" except this CPU, so we can + * touch any data without introducing corruption. We send the + * dying CPU's callbacks to an arbitrarily chosen online CPU. */ - rcu_send_cbs_to_orphanage(&rcu_bh_state); - rcu_send_cbs_to_orphanage(&rcu_sched_state); - rcu_preempt_send_cbs_to_orphanage(); + rcu_send_cbs_to_online(&rcu_bh_state); + rcu_send_cbs_to_online(&rcu_sched_state); + rcu_preempt_send_cbs_to_online(); break; case CPU_DEAD: case CPU_DEAD_FROZEN: @@ -1880,8 +2309,9 @@ static void __init rcu_init_levelspread(struct rcu_state *rsp) { int i; - for (i = NUM_RCU_LVLS - 1; i >= 0; i--) + for (i = NUM_RCU_LVLS - 1; i > 0; i--) rsp->levelspread[i] = CONFIG_RCU_FANOUT; + rsp->levelspread[0] = RCU_FANOUT_LEAF; } #else /* #ifdef CONFIG_RCU_FANOUT_EXACT */ static void __init rcu_init_levelspread(struct rcu_state *rsp) @@ -1949,10 +2379,7 @@ static void __init rcu_init_one(struct rcu_state *rsp, j / rsp->levelspread[i - 1]; } rnp->level = i; - INIT_LIST_HEAD(&rnp->blocked_tasks[0]); - INIT_LIST_HEAD(&rnp->blocked_tasks[1]); - INIT_LIST_HEAD(&rnp->blocked_tasks[2]); - INIT_LIST_HEAD(&rnp->blocked_tasks[3]); + INIT_LIST_HEAD(&rnp->blkd_tasks); } } @@ -1974,7 +2401,6 @@ void __init rcu_init(void) rcu_init_one(&rcu_sched_state, &rcu_sched_data); rcu_init_one(&rcu_bh_state, &rcu_bh_data); __rcu_init_preempt(); - open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); /* * We don't need protection against CPU-hotplug here because diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 91d4170c5c1..257664815d5 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -31,46 +31,51 @@ /* * Define shape of hierarchy based on NR_CPUS and CONFIG_RCU_FANOUT. * In theory, it should be possible to add more levels straightforwardly. - * In practice, this has not been tested, so there is probably some - * bug somewhere. + * In practice, this did work well going from three levels to four. + * Of course, your mileage may vary. */ #define MAX_RCU_LVLS 4 -#define RCU_FANOUT (CONFIG_RCU_FANOUT) -#define RCU_FANOUT_SQ (RCU_FANOUT * RCU_FANOUT) -#define RCU_FANOUT_CUBE (RCU_FANOUT_SQ * RCU_FANOUT) -#define RCU_FANOUT_FOURTH (RCU_FANOUT_CUBE * RCU_FANOUT) - -#if NR_CPUS <= RCU_FANOUT +#if CONFIG_RCU_FANOUT > 16 +#define RCU_FANOUT_LEAF 16 +#else /* #if CONFIG_RCU_FANOUT > 16 */ +#define RCU_FANOUT_LEAF (CONFIG_RCU_FANOUT) +#endif /* #else #if CONFIG_RCU_FANOUT > 16 */ +#define RCU_FANOUT_1 (RCU_FANOUT_LEAF) +#define RCU_FANOUT_2 (RCU_FANOUT_1 * CONFIG_RCU_FANOUT) +#define RCU_FANOUT_3 (RCU_FANOUT_2 * CONFIG_RCU_FANOUT) +#define RCU_FANOUT_4 (RCU_FANOUT_3 * CONFIG_RCU_FANOUT) + +#if NR_CPUS <= RCU_FANOUT_1 # define NUM_RCU_LVLS 1 # define NUM_RCU_LVL_0 1 # define NUM_RCU_LVL_1 (NR_CPUS) # define NUM_RCU_LVL_2 0 # define NUM_RCU_LVL_3 0 # define NUM_RCU_LVL_4 0 -#elif NR_CPUS <= RCU_FANOUT_SQ +#elif NR_CPUS <= RCU_FANOUT_2 # define NUM_RCU_LVLS 2 # define NUM_RCU_LVL_0 1 -# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT) +# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) # define NUM_RCU_LVL_2 (NR_CPUS) # define NUM_RCU_LVL_3 0 # define NUM_RCU_LVL_4 0 -#elif NR_CPUS <= RCU_FANOUT_CUBE +#elif NR_CPUS <= RCU_FANOUT_3 # define NUM_RCU_LVLS 3 # define NUM_RCU_LVL_0 1 -# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_SQ) -# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT) -# define NUM_RCU_LVL_3 NR_CPUS +# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2) +# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) +# define NUM_RCU_LVL_3 (NR_CPUS) # define NUM_RCU_LVL_4 0 -#elif NR_CPUS <= RCU_FANOUT_FOURTH +#elif NR_CPUS <= RCU_FANOUT_4 # define NUM_RCU_LVLS 4 # define NUM_RCU_LVL_0 1 -# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_CUBE) -# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_SQ) -# define NUM_RCU_LVL_3 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT) -# define NUM_RCU_LVL_4 NR_CPUS +# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_3) +# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_2) +# define NUM_RCU_LVL_3 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_1) +# define NUM_RCU_LVL_4 (NR_CPUS) #else # error "CONFIG_RCU_FANOUT insufficient for NR_CPUS" -#endif /* #if (NR_CPUS) <= RCU_FANOUT */ +#endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */ #define RCU_SUM (NUM_RCU_LVL_0 + NUM_RCU_LVL_1 + NUM_RCU_LVL_2 + NUM_RCU_LVL_3 + NUM_RCU_LVL_4) #define NUM_RCU_NODES (RCU_SUM - NR_CPUS) @@ -86,6 +91,14 @@ struct rcu_dynticks { /* remains even for nmi from irq handler. */ }; +/* RCU's kthread states for tracing. */ +#define RCU_KTHREAD_STOPPED 0 +#define RCU_KTHREAD_RUNNING 1 +#define RCU_KTHREAD_WAITING 2 +#define RCU_KTHREAD_OFFCPU 3 +#define RCU_KTHREAD_YIELDING 4 +#define RCU_KTHREAD_MAX 4 + /* * Definition for node within the RCU grace-period-detection hierarchy. */ @@ -104,10 +117,11 @@ struct rcu_node { /* an rcu_data structure, otherwise, each */ /* bit corresponds to a child rcu_node */ /* structure. */ - unsigned long expmask; /* Groups that have ->blocked_tasks[] */ + unsigned long expmask; /* Groups that have ->blkd_tasks */ /* elements that need to drain to allow the */ /* current expedited grace period to */ /* complete (only for TREE_PREEMPT_RCU). */ + unsigned long wakemask; /* CPUs whose kthread needs to be awakened. */ unsigned long qsmaskinit; /* Per-GP initial value for qsmask & expmask. */ unsigned long grpmask; /* Mask to apply to parent qsmask. */ @@ -117,11 +131,68 @@ struct rcu_node { u8 grpnum; /* CPU/group number for next level up. */ u8 level; /* root is at level 0. */ struct rcu_node *parent; - struct list_head blocked_tasks[4]; - /* Tasks blocked in RCU read-side critsect. */ - /* Grace period number (->gpnum) x blocked */ - /* by tasks on the (x & 0x1) element of the */ - /* blocked_tasks[] array. */ + struct list_head blkd_tasks; + /* Tasks blocked in RCU read-side critical */ + /* section. Tasks are placed at the head */ + /* of this list and age towards the tail. */ + struct list_head *gp_tasks; + /* Pointer to the first task blocking the */ + /* current grace period, or NULL if there */ + /* is no such task. */ + struct list_head *exp_tasks; + /* Pointer to the first task blocking the */ + /* current expedited grace period, or NULL */ + /* if there is no such task. If there */ + /* is no current expedited grace period, */ + /* then there can cannot be any such task. */ +#ifdef CONFIG_RCU_BOOST + struct list_head *boost_tasks; + /* Pointer to first task that needs to be */ + /* priority boosted, or NULL if no priority */ + /* boosting is needed for this rcu_node */ + /* structure. If there are no tasks */ + /* queued on this rcu_node structure that */ + /* are blocking the current grace period, */ + /* there can be no such task. */ + unsigned long boost_time; + /* When to start boosting (jiffies). */ + struct task_struct *boost_kthread_task; + /* kthread that takes care of priority */ + /* boosting for this rcu_node structure. */ + wait_queue_head_t boost_wq; + /* Wait queue on which to park the boost */ + /* kthread. */ + unsigned int boost_kthread_status; + /* State of boost_kthread_task for tracing. */ + unsigned long n_tasks_boosted; + /* Total number of tasks boosted. */ + unsigned long n_exp_boosts; + /* Number of tasks boosted for expedited GP. */ + unsigned long n_normal_boosts; + /* Number of tasks boosted for normal GP. */ + unsigned long n_balk_blkd_tasks; + /* Refused to boost: no blocked tasks. */ + unsigned long n_balk_exp_gp_tasks; + /* Refused to boost: nothing blocking GP. */ + unsigned long n_balk_boost_tasks; + /* Refused to boost: already boosting. */ + unsigned long n_balk_notblocked; + /* Refused to boost: RCU RS CS still running. */ + unsigned long n_balk_notyet; + /* Refused to boost: not yet time. */ + unsigned long n_balk_nos; + /* Refused to boost: not sure why, though. */ + /* This can happen due to race conditions. */ +#endif /* #ifdef CONFIG_RCU_BOOST */ + struct task_struct *node_kthread_task; + /* kthread that takes care of this rcu_node */ + /* structure, for example, awakening the */ + /* per-CPU kthreads as needed. */ + wait_queue_head_t node_wq; + /* Wait queue on which to park the per-node */ + /* kthread. */ + unsigned int node_kthread_status; + /* State of node_kthread_task for tracing. */ } ____cacheline_internodealigned_in_smp; /* @@ -170,7 +241,7 @@ struct rcu_data { bool passed_quiesc; /* User-mode/idle loop etc. */ bool qs_pending; /* Core waits for quiesc state. */ bool beenonline; /* CPU online at least once. */ - bool preemptable; /* Preemptable RCU? */ + bool preemptible; /* Preemptible RCU? */ struct rcu_node *mynode; /* This CPU's leaf of hierarchy */ unsigned long grpmask; /* Mask to apply to leaf qsmask. */ @@ -203,8 +274,8 @@ struct rcu_data { long qlen_last_fqs_check; /* qlen at last check for QS forcing */ unsigned long n_cbs_invoked; /* count of RCU cbs invoked. */ - unsigned long n_cbs_orphaned; /* RCU cbs sent to orphanage. */ - unsigned long n_cbs_adopted; /* RCU cbs adopted from orphanage. */ + unsigned long n_cbs_orphaned; /* RCU cbs orphaned by dying CPU */ + unsigned long n_cbs_adopted; /* RCU cbs adopted from dying CPU */ unsigned long n_force_qs_snap; /* did other CPU force QS recently? */ long blimit; /* Upper limit on a processed batch */ @@ -249,7 +320,6 @@ struct rcu_data { #endif /* #else #ifdef CONFIG_NO_HZ */ #define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR #ifdef CONFIG_PROVE_RCU #define RCU_STALL_DELAY_DELTA (5 * HZ) @@ -267,13 +337,6 @@ struct rcu_data { /* scheduling clock irq */ /* before ratting on them. */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR_RUNNABLE -#define RCU_CPU_STALL_SUPPRESS_INIT 0 -#else -#define RCU_CPU_STALL_SUPPRESS_INIT 1 -#endif - -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ /* * RCU global state, including node hierarchy. This hierarchy is @@ -309,15 +372,7 @@ struct rcu_state { /* End of fields guarded by root rcu_node's lock. */ raw_spinlock_t onofflock; /* exclude on/offline and */ - /* starting new GP. Also */ - /* protects the following */ - /* orphan_cbs fields. */ - struct rcu_head *orphan_cbs_list; /* list of rcu_head structs */ - /* orphaned by all CPUs in */ - /* a given leaf rcu_node */ - /* going offline. */ - struct rcu_head **orphan_cbs_tail; /* And tail pointer. */ - long orphan_qlen; /* Number of orphaned cbs. */ + /* starting new GP. */ raw_spinlock_t fqslock; /* Only one task forcing */ /* quiescent states. */ unsigned long jiffies_force_qs; /* Time at which to invoke */ @@ -328,12 +383,12 @@ struct rcu_state { /* due to lock unavailable. */ unsigned long n_force_qs_ngp; /* Number of calls leaving */ /* due to no GP active. */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR unsigned long gp_start; /* Time at which GP started, */ /* but in jiffies. */ unsigned long jiffies_stall; /* Time at which to check */ /* for CPU stalls. */ -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ + unsigned long gp_max; /* Maximum GP duration in */ + /* jiffies. */ char *name; /* Name of structure. */ }; @@ -364,16 +419,14 @@ DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data); static void rcu_bootup_announce(void); long rcu_batches_completed(void); static void rcu_preempt_note_context_switch(int cpu); -static int rcu_preempted_readers(struct rcu_node *rnp); +static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp); #ifdef CONFIG_HOTPLUG_CPU static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR static void rcu_print_detail_task_stall(struct rcu_state *rsp); static void rcu_print_task_stall(struct rcu_node *rnp); static void rcu_preempt_stall_reset(void); -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp); #ifdef CONFIG_HOTPLUG_CPU static int rcu_preempt_offline_tasks(struct rcu_state *rsp, @@ -390,8 +443,16 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp); static int rcu_preempt_pending(int cpu); static int rcu_preempt_needs_cpu(int cpu); static void __cpuinit rcu_preempt_init_percpu_data(int cpu); -static void rcu_preempt_send_cbs_to_orphanage(void); +static void rcu_preempt_send_cbs_to_online(void); static void __init __rcu_init_preempt(void); static void rcu_needs_cpu_flush(void); +static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp); +static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); +static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, + cpumask_var_t cm); +static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); +static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, + struct rcu_node *rnp, + int rnp_index); #endif /* #ifndef RCU_TREE_NONCORE */ diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 71a4147473f..3f6559a5f5c 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1,7 +1,7 @@ /* * Read-Copy Update mechanism for mutual exclusion (tree-based version) * Internal non-public definitions that provide either classic - * or preemptable semantics. + * or preemptible semantics. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -25,6 +25,7 @@ */ #include <linux/delay.h> +#include <linux/stop_machine.h> /* * Check the RCU kernel configuration parameters and print informative @@ -53,10 +54,6 @@ static void __init rcu_bootup_announce_oddness(void) #ifdef CONFIG_RCU_TORTURE_TEST_RUNNABLE printk(KERN_INFO "\tRCU torture testing starts during boot.\n"); #endif -#ifndef CONFIG_RCU_CPU_STALL_DETECTOR - printk(KERN_INFO - "\tRCU-based detection of stalled CPUs is disabled.\n"); -#endif #if defined(CONFIG_TREE_PREEMPT_RCU) && !defined(CONFIG_RCU_CPU_STALL_VERBOSE) printk(KERN_INFO "\tVerbose stalled-CPUs detection is disabled.\n"); #endif @@ -69,6 +66,7 @@ static void __init rcu_bootup_announce_oddness(void) struct rcu_state rcu_preempt_state = RCU_STATE_INITIALIZER(rcu_preempt_state); DEFINE_PER_CPU(struct rcu_data, rcu_preempt_data); +static struct rcu_state *rcu_state = &rcu_preempt_state; static int rcu_preempted_readers_exp(struct rcu_node *rnp); @@ -77,7 +75,7 @@ static int rcu_preempted_readers_exp(struct rcu_node *rnp); */ static void __init rcu_bootup_announce(void) { - printk(KERN_INFO "Preemptable hierarchical RCU implementation.\n"); + printk(KERN_INFO "Preemptible hierarchical RCU implementation.\n"); rcu_bootup_announce_oddness(); } @@ -110,7 +108,7 @@ void rcu_force_quiescent_state(void) EXPORT_SYMBOL_GPL(rcu_force_quiescent_state); /* - * Record a preemptable-RCU quiescent state for the specified CPU. Note + * Record a preemptible-RCU quiescent state for the specified CPU. Note * that this just means that the task currently running on the CPU is * not in a quiescent state. There might be any number of tasks blocked * while in an RCU read-side critical section. @@ -133,12 +131,12 @@ static void rcu_preempt_qs(int cpu) * We have entered the scheduler, and the current task might soon be * context-switched away from. If this task is in an RCU read-side * critical section, we will no longer be able to rely on the CPU to - * record that fact, so we enqueue the task on the appropriate entry - * of the blocked_tasks[] array. The task will dequeue itself when - * it exits the outermost enclosing RCU read-side critical section. - * Therefore, the current grace period cannot be permitted to complete - * until the blocked_tasks[] entry indexed by the low-order bit of - * rnp->gpnum empties. + * record that fact, so we enqueue the task on the blkd_tasks list. + * The task will dequeue itself when it exits the outermost enclosing + * RCU read-side critical section. Therefore, the current grace period + * cannot be permitted to complete until the blkd_tasks list entries + * predating the current grace period drain, in other words, until + * rnp->gp_tasks becomes NULL. * * Caller must disable preemption. */ @@ -146,7 +144,6 @@ static void rcu_preempt_note_context_switch(int cpu) { struct task_struct *t = current; unsigned long flags; - int phase; struct rcu_data *rdp; struct rcu_node *rnp; @@ -168,15 +165,30 @@ static void rcu_preempt_note_context_switch(int cpu) * (i.e., this CPU has not yet passed through a quiescent * state for the current grace period), then as long * as that task remains queued, the current grace period - * cannot end. + * cannot end. Note that there is some uncertainty as + * to exactly when the current grace period started. + * We take a conservative approach, which can result + * in unnecessarily waiting on tasks that started very + * slightly after the current grace period began. C'est + * la vie!!! * * But first, note that the current CPU must still be * on line! */ WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0); WARN_ON_ONCE(!list_empty(&t->rcu_node_entry)); - phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1; - list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]); + if ((rnp->qsmask & rdp->grpmask) && rnp->gp_tasks != NULL) { + list_add(&t->rcu_node_entry, rnp->gp_tasks->prev); + rnp->gp_tasks = &t->rcu_node_entry; +#ifdef CONFIG_RCU_BOOST + if (rnp->boost_tasks != NULL) + rnp->boost_tasks = rnp->gp_tasks; +#endif /* #ifdef CONFIG_RCU_BOOST */ + } else { + list_add(&t->rcu_node_entry, &rnp->blkd_tasks); + if (rnp->qsmask & rdp->grpmask) + rnp->gp_tasks = &t->rcu_node_entry; + } raw_spin_unlock_irqrestore(&rnp->lock, flags); } @@ -195,7 +207,7 @@ static void rcu_preempt_note_context_switch(int cpu) } /* - * Tree-preemptable RCU implementation for rcu_read_lock(). + * Tree-preemptible RCU implementation for rcu_read_lock(). * Just increment ->rcu_read_lock_nesting, shared state will be updated * if we block. */ @@ -211,12 +223,9 @@ EXPORT_SYMBOL_GPL(__rcu_read_lock); * for the specified rcu_node structure. If the caller needs a reliable * answer, it must hold the rcu_node's ->lock. */ -static int rcu_preempted_readers(struct rcu_node *rnp) +static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp) { - int phase = rnp->gpnum & 0x1; - - return !list_empty(&rnp->blocked_tasks[phase]) || - !list_empty(&rnp->blocked_tasks[phase + 2]); + return rnp->gp_tasks != NULL; } /* @@ -232,7 +241,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags) unsigned long mask; struct rcu_node *rnp_p; - if (rnp->qsmask != 0 || rcu_preempted_readers(rnp)) { + if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); return; /* Still need more quiescent states! */ } @@ -256,6 +265,21 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags) } /* + * Advance a ->blkd_tasks-list pointer to the next entry, instead + * returning NULL if at the end of the list. + */ +static struct list_head *rcu_next_node_entry(struct task_struct *t, + struct rcu_node *rnp) +{ + struct list_head *np; + + np = t->rcu_node_entry.next; + if (np == &rnp->blkd_tasks) + np = NULL; + return np; +} + +/* * Handle special cases during rcu_read_unlock(), such as needing to * notify RCU core processing or task having blocked during the RCU * read-side critical section. @@ -265,6 +289,7 @@ static void rcu_read_unlock_special(struct task_struct *t) int empty; int empty_exp; unsigned long flags; + struct list_head *np; struct rcu_node *rnp; int special; @@ -305,10 +330,19 @@ static void rcu_read_unlock_special(struct task_struct *t) break; raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ } - empty = !rcu_preempted_readers(rnp); + empty = !rcu_preempt_blocked_readers_cgp(rnp); empty_exp = !rcu_preempted_readers_exp(rnp); smp_mb(); /* ensure expedited fastpath sees end of RCU c-s. */ + np = rcu_next_node_entry(t, rnp); list_del_init(&t->rcu_node_entry); + if (&t->rcu_node_entry == rnp->gp_tasks) + rnp->gp_tasks = np; + if (&t->rcu_node_entry == rnp->exp_tasks) + rnp->exp_tasks = np; +#ifdef CONFIG_RCU_BOOST + if (&t->rcu_node_entry == rnp->boost_tasks) + rnp->boost_tasks = np; +#endif /* #ifdef CONFIG_RCU_BOOST */ t->rcu_blocked_node = NULL; /* @@ -321,6 +355,15 @@ static void rcu_read_unlock_special(struct task_struct *t) else rcu_report_unblock_qs_rnp(rnp, flags); +#ifdef CONFIG_RCU_BOOST + /* Unboost if we were boosted. */ + if (special & RCU_READ_UNLOCK_BOOSTED) { + t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_BOOSTED; + rt_mutex_unlock(t->rcu_boost_mutex); + t->rcu_boost_mutex = NULL; + } +#endif /* #ifdef CONFIG_RCU_BOOST */ + /* * If this was the last task on the expedited lists, * then we need to report up the rcu_node hierarchy. @@ -333,7 +376,7 @@ static void rcu_read_unlock_special(struct task_struct *t) } /* - * Tree-preemptable RCU implementation for rcu_read_unlock(). + * Tree-preemptible RCU implementation for rcu_read_unlock(). * Decrement ->rcu_read_lock_nesting. If the result is zero (outermost * rcu_read_unlock()) and ->rcu_read_unlock_special is non-zero, then * invoke rcu_read_unlock_special() to clean up after a context switch @@ -355,8 +398,6 @@ void __rcu_read_unlock(void) } EXPORT_SYMBOL_GPL(__rcu_read_unlock); -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR - #ifdef CONFIG_RCU_CPU_STALL_VERBOSE /* @@ -366,18 +407,16 @@ EXPORT_SYMBOL_GPL(__rcu_read_unlock); static void rcu_print_detail_task_stall_rnp(struct rcu_node *rnp) { unsigned long flags; - struct list_head *lp; - int phase; struct task_struct *t; - if (rcu_preempted_readers(rnp)) { - raw_spin_lock_irqsave(&rnp->lock, flags); - phase = rnp->gpnum & 0x1; - lp = &rnp->blocked_tasks[phase]; - list_for_each_entry(t, lp, rcu_node_entry) - sched_show_task(t); - raw_spin_unlock_irqrestore(&rnp->lock, flags); - } + if (!rcu_preempt_blocked_readers_cgp(rnp)) + return; + raw_spin_lock_irqsave(&rnp->lock, flags); + t = list_entry(rnp->gp_tasks, + struct task_struct, rcu_node_entry); + list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) + sched_show_task(t); + raw_spin_unlock_irqrestore(&rnp->lock, flags); } /* @@ -407,16 +446,14 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp) */ static void rcu_print_task_stall(struct rcu_node *rnp) { - struct list_head *lp; - int phase; struct task_struct *t; - if (rcu_preempted_readers(rnp)) { - phase = rnp->gpnum & 0x1; - lp = &rnp->blocked_tasks[phase]; - list_for_each_entry(t, lp, rcu_node_entry) - printk(" P%d", t->pid); - } + if (!rcu_preempt_blocked_readers_cgp(rnp)) + return; + t = list_entry(rnp->gp_tasks, + struct task_struct, rcu_node_entry); + list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) + printk(" P%d", t->pid); } /* @@ -429,18 +466,21 @@ static void rcu_preempt_stall_reset(void) rcu_preempt_state.jiffies_stall = jiffies + ULONG_MAX / 2; } -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ - /* * Check that the list of blocked tasks for the newly completed grace * period is in fact empty. It is a serious bug to complete a grace * period that still has RCU readers blocked! This function must be * invoked -before- updating this rnp's ->gpnum, and the rnp's ->lock * must be held by the caller. + * + * Also, if there are blocked tasks on the list, they automatically + * block the newly created grace period, so set up ->gp_tasks accordingly. */ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp) { - WARN_ON_ONCE(rcu_preempted_readers(rnp)); + WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp)); + if (!list_empty(&rnp->blkd_tasks)) + rnp->gp_tasks = rnp->blkd_tasks.next; WARN_ON_ONCE(rnp->qsmask); } @@ -464,50 +504,68 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp) { - int i; struct list_head *lp; struct list_head *lp_root; int retval = 0; struct rcu_node *rnp_root = rcu_get_root(rsp); - struct task_struct *tp; + struct task_struct *t; if (rnp == rnp_root) { WARN_ONCE(1, "Last CPU thought to be offlined?"); return 0; /* Shouldn't happen: at least one CPU online. */ } - WARN_ON_ONCE(rnp != rdp->mynode && - (!list_empty(&rnp->blocked_tasks[0]) || - !list_empty(&rnp->blocked_tasks[1]) || - !list_empty(&rnp->blocked_tasks[2]) || - !list_empty(&rnp->blocked_tasks[3]))); + + /* If we are on an internal node, complain bitterly. */ + WARN_ON_ONCE(rnp != rdp->mynode); /* - * Move tasks up to root rcu_node. Rely on the fact that the - * root rcu_node can be at most one ahead of the rest of the - * rcu_nodes in terms of gp_num value. This fact allows us to - * move the blocked_tasks[] array directly, element by element. + * Move tasks up to root rcu_node. Don't try to get fancy for + * this corner-case operation -- just put this node's tasks + * at the head of the root node's list, and update the root node's + * ->gp_tasks and ->exp_tasks pointers to those of this node's, + * if non-NULL. This might result in waiting for more tasks than + * absolutely necessary, but this is a good performance/complexity + * tradeoff. */ - if (rcu_preempted_readers(rnp)) + if (rcu_preempt_blocked_readers_cgp(rnp)) retval |= RCU_OFL_TASKS_NORM_GP; if (rcu_preempted_readers_exp(rnp)) retval |= RCU_OFL_TASKS_EXP_GP; - for (i = 0; i < 4; i++) { - lp = &rnp->blocked_tasks[i]; - lp_root = &rnp_root->blocked_tasks[i]; - while (!list_empty(lp)) { - tp = list_entry(lp->next, typeof(*tp), rcu_node_entry); - raw_spin_lock(&rnp_root->lock); /* irqs already disabled */ - list_del(&tp->rcu_node_entry); - tp->rcu_blocked_node = rnp_root; - list_add(&tp->rcu_node_entry, lp_root); - raw_spin_unlock(&rnp_root->lock); /* irqs remain disabled */ - } + lp = &rnp->blkd_tasks; + lp_root = &rnp_root->blkd_tasks; + while (!list_empty(lp)) { + t = list_entry(lp->next, typeof(*t), rcu_node_entry); + raw_spin_lock(&rnp_root->lock); /* irqs already disabled */ + list_del(&t->rcu_node_entry); + t->rcu_blocked_node = rnp_root; + list_add(&t->rcu_node_entry, lp_root); + if (&t->rcu_node_entry == rnp->gp_tasks) + rnp_root->gp_tasks = rnp->gp_tasks; + if (&t->rcu_node_entry == rnp->exp_tasks) + rnp_root->exp_tasks = rnp->exp_tasks; +#ifdef CONFIG_RCU_BOOST + if (&t->rcu_node_entry == rnp->boost_tasks) + rnp_root->boost_tasks = rnp->boost_tasks; +#endif /* #ifdef CONFIG_RCU_BOOST */ + raw_spin_unlock(&rnp_root->lock); /* irqs still disabled */ } + +#ifdef CONFIG_RCU_BOOST + /* In case root is being boosted and leaf is not. */ + raw_spin_lock(&rnp_root->lock); /* irqs already disabled */ + if (rnp_root->boost_tasks != NULL && + rnp_root->boost_tasks != rnp_root->gp_tasks) + rnp_root->boost_tasks = rnp_root->gp_tasks; + raw_spin_unlock(&rnp_root->lock); /* irqs still disabled */ +#endif /* #ifdef CONFIG_RCU_BOOST */ + + rnp->gp_tasks = NULL; + rnp->exp_tasks = NULL; return retval; } /* - * Do CPU-offline processing for preemptable RCU. + * Do CPU-offline processing for preemptible RCU. */ static void rcu_preempt_offline_cpu(int cpu) { @@ -536,7 +594,7 @@ static void rcu_preempt_check_callbacks(int cpu) } /* - * Process callbacks for preemptable RCU. + * Process callbacks for preemptible RCU. */ static void rcu_preempt_process_callbacks(void) { @@ -545,7 +603,7 @@ static void rcu_preempt_process_callbacks(void) } /* - * Queue a preemptable-RCU callback for invocation after a grace period. + * Queue a preemptible-RCU callback for invocation after a grace period. */ void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) { @@ -593,8 +651,7 @@ static DEFINE_MUTEX(sync_rcu_preempt_exp_mutex); */ static int rcu_preempted_readers_exp(struct rcu_node *rnp) { - return !list_empty(&rnp->blocked_tasks[2]) || - !list_empty(&rnp->blocked_tasks[3]); + return rnp->exp_tasks != NULL; } /* @@ -654,13 +711,17 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp) static void sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp) { - int must_wait; + unsigned long flags; + int must_wait = 0; - raw_spin_lock(&rnp->lock); /* irqs already disabled */ - list_splice_init(&rnp->blocked_tasks[0], &rnp->blocked_tasks[2]); - list_splice_init(&rnp->blocked_tasks[1], &rnp->blocked_tasks[3]); - must_wait = rcu_preempted_readers_exp(rnp); - raw_spin_unlock(&rnp->lock); /* irqs remain disabled */ + raw_spin_lock_irqsave(&rnp->lock, flags); + if (list_empty(&rnp->blkd_tasks)) + raw_spin_unlock_irqrestore(&rnp->lock, flags); + else { + rnp->exp_tasks = rnp->blkd_tasks.next; + rcu_initiate_boost(rnp, flags); /* releases rnp->lock */ + must_wait = 1; + } if (!must_wait) rcu_report_exp_rnp(rsp, rnp); } @@ -668,9 +729,7 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp) /* * Wait for an rcu-preempt grace period, but expedite it. The basic idea * is to invoke synchronize_sched_expedited() to push all the tasks to - * the ->blocked_tasks[] lists, move all entries from the first set of - * ->blocked_tasks[] lists to the second set, and finally wait for this - * second set to drain. + * the ->blkd_tasks lists and wait for this list to drain. */ void synchronize_rcu_expedited(void) { @@ -702,7 +761,7 @@ void synchronize_rcu_expedited(void) if ((ACCESS_ONCE(sync_rcu_preempt_exp_count) - snap) > 0) goto unlock_mb_ret; /* Others did our work for us. */ - /* force all RCU readers onto blocked_tasks[]. */ + /* force all RCU readers onto ->blkd_tasks lists. */ synchronize_sched_expedited(); raw_spin_lock_irqsave(&rsp->onofflock, flags); @@ -714,7 +773,7 @@ void synchronize_rcu_expedited(void) raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ } - /* Snapshot current state of ->blocked_tasks[] lists. */ + /* Snapshot current state of ->blkd_tasks lists. */ rcu_for_each_leaf_node(rsp, rnp) sync_rcu_preempt_exp_init(rsp, rnp); if (NUM_RCU_NODES > 1) @@ -722,7 +781,7 @@ void synchronize_rcu_expedited(void) raw_spin_unlock_irqrestore(&rsp->onofflock, flags); - /* Wait for snapshotted ->blocked_tasks[] lists to drain. */ + /* Wait for snapshotted ->blkd_tasks lists to drain. */ rnp = rcu_get_root(rsp); wait_event(sync_rcu_preempt_exp_wq, sync_rcu_preempt_exp_done(rnp)); @@ -738,7 +797,7 @@ mb_ret: EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); /* - * Check to see if there is any immediate preemptable-RCU-related work + * Check to see if there is any immediate preemptible-RCU-related work * to be done. */ static int rcu_preempt_pending(int cpu) @@ -748,7 +807,7 @@ static int rcu_preempt_pending(int cpu) } /* - * Does preemptable RCU need the CPU to stay out of dynticks mode? + * Does preemptible RCU need the CPU to stay out of dynticks mode? */ static int rcu_preempt_needs_cpu(int cpu) { @@ -765,7 +824,7 @@ void rcu_barrier(void) EXPORT_SYMBOL_GPL(rcu_barrier); /* - * Initialize preemptable RCU's per-CPU data. + * Initialize preemptible RCU's per-CPU data. */ static void __cpuinit rcu_preempt_init_percpu_data(int cpu) { @@ -773,15 +832,15 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu) } /* - * Move preemptable RCU's callbacks to ->orphan_cbs_list. + * Move preemptible RCU's callbacks from dying CPU to other online CPU. */ -static void rcu_preempt_send_cbs_to_orphanage(void) +static void rcu_preempt_send_cbs_to_online(void) { - rcu_send_cbs_to_orphanage(&rcu_preempt_state); + rcu_send_cbs_to_online(&rcu_preempt_state); } /* - * Initialize preemptable RCU's state structures. + * Initialize preemptible RCU's state structures. */ static void __init __rcu_init_preempt(void) { @@ -789,7 +848,7 @@ static void __init __rcu_init_preempt(void) } /* - * Check for a task exiting while in a preemptable-RCU read-side + * Check for a task exiting while in a preemptible-RCU read-side * critical section, clean up if so. No need to issue warnings, * as debug_check_no_locks_held() already does this if lockdep * is enabled. @@ -801,11 +860,13 @@ void exit_rcu(void) if (t->rcu_read_lock_nesting == 0) return; t->rcu_read_lock_nesting = 1; - rcu_read_unlock(); + __rcu_read_unlock(); } #else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ +static struct rcu_state *rcu_state = &rcu_sched_state; + /* * Tell them what RCU they are running. */ @@ -835,7 +896,7 @@ void rcu_force_quiescent_state(void) EXPORT_SYMBOL_GPL(rcu_force_quiescent_state); /* - * Because preemptable RCU does not exist, we never have to check for + * Because preemptible RCU does not exist, we never have to check for * CPUs being in quiescent states. */ static void rcu_preempt_note_context_switch(int cpu) @@ -843,10 +904,10 @@ static void rcu_preempt_note_context_switch(int cpu) } /* - * Because preemptable RCU does not exist, there are never any preempted + * Because preemptible RCU does not exist, there are never any preempted * RCU readers. */ -static int rcu_preempted_readers(struct rcu_node *rnp) +static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp) { return 0; } @@ -861,10 +922,8 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags) #endif /* #ifdef CONFIG_HOTPLUG_CPU */ -#ifdef CONFIG_RCU_CPU_STALL_DETECTOR - /* - * Because preemptable RCU does not exist, we never have to check for + * Because preemptible RCU does not exist, we never have to check for * tasks blocked within RCU read-side critical sections. */ static void rcu_print_detail_task_stall(struct rcu_state *rsp) @@ -872,7 +931,7 @@ static void rcu_print_detail_task_stall(struct rcu_state *rsp) } /* - * Because preemptable RCU does not exist, we never have to check for + * Because preemptible RCU does not exist, we never have to check for * tasks blocked within RCU read-side critical sections. */ static void rcu_print_task_stall(struct rcu_node *rnp) @@ -887,10 +946,8 @@ static void rcu_preempt_stall_reset(void) { } -#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ - /* - * Because there is no preemptable RCU, there can be no readers blocked, + * Because there is no preemptible RCU, there can be no readers blocked, * so there is no need to check for blocked tasks. So check only for * bogus qsmask values. */ @@ -902,7 +959,7 @@ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp) #ifdef CONFIG_HOTPLUG_CPU /* - * Because preemptable RCU does not exist, it never needs to migrate + * Because preemptible RCU does not exist, it never needs to migrate * tasks that were blocked within RCU read-side critical sections, and * such non-existent tasks cannot possibly have been blocking the current * grace period. @@ -915,7 +972,7 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp, } /* - * Because preemptable RCU does not exist, it never needs CPU-offline + * Because preemptible RCU does not exist, it never needs CPU-offline * processing. */ static void rcu_preempt_offline_cpu(int cpu) @@ -925,7 +982,7 @@ static void rcu_preempt_offline_cpu(int cpu) #endif /* #ifdef CONFIG_HOTPLUG_CPU */ /* - * Because preemptable RCU does not exist, it never has any callbacks + * Because preemptible RCU does not exist, it never has any callbacks * to check. */ static void rcu_preempt_check_callbacks(int cpu) @@ -933,7 +990,7 @@ static void rcu_preempt_check_callbacks(int cpu) } /* - * Because preemptable RCU does not exist, it never has any callbacks + * Because preemptible RCU does not exist, it never has any callbacks * to process. */ static void rcu_preempt_process_callbacks(void) @@ -942,7 +999,7 @@ static void rcu_preempt_process_callbacks(void) /* * Wait for an rcu-preempt grace period, but make it happen quickly. - * But because preemptable RCU does not exist, map to rcu-sched. + * But because preemptible RCU does not exist, map to rcu-sched. */ void synchronize_rcu_expedited(void) { @@ -953,7 +1010,7 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited); #ifdef CONFIG_HOTPLUG_CPU /* - * Because preemptable RCU does not exist, there is never any need to + * Because preemptible RCU does not exist, there is never any need to * report on tasks preempted in RCU read-side critical sections during * expedited RCU grace periods. */ @@ -965,7 +1022,7 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp) #endif /* #ifdef CONFIG_HOTPLUG_CPU */ /* - * Because preemptable RCU does not exist, it never has any work to do. + * Because preemptible RCU does not exist, it never has any work to do. */ static int rcu_preempt_pending(int cpu) { @@ -973,7 +1030,7 @@ static int rcu_preempt_pending(int cpu) } /* - * Because preemptable RCU does not exist, it never needs any CPU. + * Because preemptible RCU does not exist, it never needs any CPU. */ static int rcu_preempt_needs_cpu(int cpu) { @@ -981,7 +1038,7 @@ static int rcu_preempt_needs_cpu(int cpu) } /* - * Because preemptable RCU does not exist, rcu_barrier() is just + * Because preemptible RCU does not exist, rcu_barrier() is just * another name for rcu_barrier_sched(). */ void rcu_barrier(void) @@ -991,7 +1048,7 @@ void rcu_barrier(void) EXPORT_SYMBOL_GPL(rcu_barrier); /* - * Because preemptable RCU does not exist, there is no per-CPU + * Because preemptible RCU does not exist, there is no per-CPU * data to initialize. */ static void __cpuinit rcu_preempt_init_percpu_data(int cpu) @@ -999,14 +1056,14 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu) } /* - * Because there is no preemptable RCU, there are no callbacks to move. + * Because there is no preemptible RCU, there are no callbacks to move. */ -static void rcu_preempt_send_cbs_to_orphanage(void) +static void rcu_preempt_send_cbs_to_online(void) { } /* - * Because preemptable RCU does not exist, it need not be initialized. + * Because preemptible RCU does not exist, it need not be initialized. */ static void __init __rcu_init_preempt(void) { @@ -1014,6 +1071,402 @@ static void __init __rcu_init_preempt(void) #endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ +#ifdef CONFIG_RCU_BOOST + +#include "rtmutex_common.h" + +#ifdef CONFIG_RCU_TRACE + +static void rcu_initiate_boost_trace(struct rcu_node *rnp) +{ + if (list_empty(&rnp->blkd_tasks)) + rnp->n_balk_blkd_tasks++; + else if (rnp->exp_tasks == NULL && rnp->gp_tasks == NULL) + rnp->n_balk_exp_gp_tasks++; + else if (rnp->gp_tasks != NULL && rnp->boost_tasks != NULL) + rnp->n_balk_boost_tasks++; + else if (rnp->gp_tasks != NULL && rnp->qsmask != 0) + rnp->n_balk_notblocked++; + else if (rnp->gp_tasks != NULL && + ULONG_CMP_LT(jiffies, rnp->boost_time)) + rnp->n_balk_notyet++; + else + rnp->n_balk_nos++; +} + +#else /* #ifdef CONFIG_RCU_TRACE */ + +static void rcu_initiate_boost_trace(struct rcu_node *rnp) +{ +} + +#endif /* #else #ifdef CONFIG_RCU_TRACE */ + +/* + * Carry out RCU priority boosting on the task indicated by ->exp_tasks + * or ->boost_tasks, advancing the pointer to the next task in the + * ->blkd_tasks list. + * + * Note that irqs must be enabled: boosting the task can block. + * Returns 1 if there are more tasks needing to be boosted. + */ +static int rcu_boost(struct rcu_node *rnp) +{ + unsigned long flags; + struct rt_mutex mtx; + struct task_struct *t; + struct list_head *tb; + + if (rnp->exp_tasks == NULL && rnp->boost_tasks == NULL) + return 0; /* Nothing left to boost. */ + + raw_spin_lock_irqsave(&rnp->lock, flags); + + /* + * Recheck under the lock: all tasks in need of boosting + * might exit their RCU read-side critical sections on their own. + */ + if (rnp->exp_tasks == NULL && rnp->boost_tasks == NULL) { + raw_spin_unlock_irqrestore(&rnp->lock, flags); + return 0; + } + + /* + * Preferentially boost tasks blocking expedited grace periods. + * This cannot starve the normal grace periods because a second + * expedited grace period must boost all blocked tasks, including + * those blocking the pre-existing normal grace period. + */ + if (rnp->exp_tasks != NULL) { + tb = rnp->exp_tasks; + rnp->n_exp_boosts++; + } else { + tb = rnp->boost_tasks; + rnp->n_normal_boosts++; + } + rnp->n_tasks_boosted++; + + /* + * We boost task t by manufacturing an rt_mutex that appears to + * be held by task t. We leave a pointer to that rt_mutex where + * task t can find it, and task t will release the mutex when it + * exits its outermost RCU read-side critical section. Then + * simply acquiring this artificial rt_mutex will boost task + * t's priority. (Thanks to tglx for suggesting this approach!) + * + * Note that task t must acquire rnp->lock to remove itself from + * the ->blkd_tasks list, which it will do from exit() if from + * nowhere else. We therefore are guaranteed that task t will + * stay around at least until we drop rnp->lock. Note that + * rnp->lock also resolves races between our priority boosting + * and task t's exiting its outermost RCU read-side critical + * section. + */ + t = container_of(tb, struct task_struct, rcu_node_entry); + rt_mutex_init_proxy_locked(&mtx, t); + t->rcu_boost_mutex = &mtx; + t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BOOSTED; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + rt_mutex_lock(&mtx); /* Side effect: boosts task t's priority. */ + rt_mutex_unlock(&mtx); /* Keep lockdep happy. */ + + return rnp->exp_tasks != NULL || rnp->boost_tasks != NULL; +} + +/* + * Timer handler to initiate waking up of boost kthreads that + * have yielded the CPU due to excessive numbers of tasks to + * boost. We wake up the per-rcu_node kthread, which in turn + * will wake up the booster kthread. + */ +static void rcu_boost_kthread_timer(unsigned long arg) +{ + invoke_rcu_node_kthread((struct rcu_node *)arg); +} + +/* + * Priority-boosting kthread. One per leaf rcu_node and one for the + * root rcu_node. + */ +static int rcu_boost_kthread(void *arg) +{ + struct rcu_node *rnp = (struct rcu_node *)arg; + int spincnt = 0; + int more2boost; + + for (;;) { + rnp->boost_kthread_status = RCU_KTHREAD_WAITING; + wait_event_interruptible(rnp->boost_wq, rnp->boost_tasks || + rnp->exp_tasks); + rnp->boost_kthread_status = RCU_KTHREAD_RUNNING; + more2boost = rcu_boost(rnp); + if (more2boost) + spincnt++; + else + spincnt = 0; + if (spincnt > 10) { + rcu_yield(rcu_boost_kthread_timer, (unsigned long)rnp); + spincnt = 0; + } + } + /* NOTREACHED */ + return 0; +} + +/* + * Check to see if it is time to start boosting RCU readers that are + * blocking the current grace period, and, if so, tell the per-rcu_node + * kthread to start boosting them. If there is an expedited grace + * period in progress, it is always time to boost. + * + * The caller must hold rnp->lock, which this function releases, + * but irqs remain disabled. The ->boost_kthread_task is immortal, + * so we don't need to worry about it going away. + */ +static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags) +{ + struct task_struct *t; + + if (!rcu_preempt_blocked_readers_cgp(rnp) && rnp->exp_tasks == NULL) { + rnp->n_balk_exp_gp_tasks++; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + return; + } + if (rnp->exp_tasks != NULL || + (rnp->gp_tasks != NULL && + rnp->boost_tasks == NULL && + rnp->qsmask == 0 && + ULONG_CMP_GE(jiffies, rnp->boost_time))) { + if (rnp->exp_tasks == NULL) + rnp->boost_tasks = rnp->gp_tasks; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + t = rnp->boost_kthread_task; + if (t != NULL) + wake_up_process(t); + } else { + rcu_initiate_boost_trace(rnp); + raw_spin_unlock_irqrestore(&rnp->lock, flags); + } +} + +/* + * Set the affinity of the boost kthread. The CPU-hotplug locks are + * held, so no one should be messing with the existence of the boost + * kthread. + */ +static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, + cpumask_var_t cm) +{ + struct task_struct *t; + + t = rnp->boost_kthread_task; + if (t != NULL) + set_cpus_allowed_ptr(rnp->boost_kthread_task, cm); +} + +#define RCU_BOOST_DELAY_JIFFIES DIV_ROUND_UP(CONFIG_RCU_BOOST_DELAY * HZ, 1000) + +/* + * Do priority-boost accounting for the start of a new grace period. + */ +static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) +{ + rnp->boost_time = jiffies + RCU_BOOST_DELAY_JIFFIES; +} + +/* + * Initialize the RCU-boost waitqueue. + */ +static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp) +{ + init_waitqueue_head(&rnp->boost_wq); +} + +/* + * Create an RCU-boost kthread for the specified node if one does not + * already exist. We only create this kthread for preemptible RCU. + * Returns zero if all is well, a negated errno otherwise. + */ +static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, + struct rcu_node *rnp, + int rnp_index) +{ + unsigned long flags; + struct sched_param sp; + struct task_struct *t; + + if (&rcu_preempt_state != rsp) + return 0; + if (rnp->boost_kthread_task != NULL) + return 0; + t = kthread_create(rcu_boost_kthread, (void *)rnp, + "rcub%d", rnp_index); + if (IS_ERR(t)) + return PTR_ERR(t); + raw_spin_lock_irqsave(&rnp->lock, flags); + rnp->boost_kthread_task = t; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + wake_up_process(t); + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(t, SCHED_FIFO, &sp); + return 0; +} + +#else /* #ifdef CONFIG_RCU_BOOST */ + +static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags) +{ + raw_spin_unlock_irqrestore(&rnp->lock, flags); +} + +static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, + cpumask_var_t cm) +{ +} + +static void rcu_preempt_boost_start_gp(struct rcu_node *rnp) +{ +} + +static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp) +{ +} + +static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp, + struct rcu_node *rnp, + int rnp_index) +{ + return 0; +} + +#endif /* #else #ifdef CONFIG_RCU_BOOST */ + +#ifndef CONFIG_SMP + +void synchronize_sched_expedited(void) +{ + cond_resched(); +} +EXPORT_SYMBOL_GPL(synchronize_sched_expedited); + +#else /* #ifndef CONFIG_SMP */ + +static atomic_t sync_sched_expedited_started = ATOMIC_INIT(0); +static atomic_t sync_sched_expedited_done = ATOMIC_INIT(0); + +static int synchronize_sched_expedited_cpu_stop(void *data) +{ + /* + * There must be a full memory barrier on each affected CPU + * between the time that try_stop_cpus() is called and the + * time that it returns. + * + * In the current initial implementation of cpu_stop, the + * above condition is already met when the control reaches + * this point and the following smp_mb() is not strictly + * necessary. Do smp_mb() anyway for documentation and + * robustness against future implementation changes. + */ + smp_mb(); /* See above comment block. */ + return 0; +} + +/* + * Wait for an rcu-sched grace period to elapse, but use "big hammer" + * approach to force grace period to end quickly. This consumes + * significant time on all CPUs, and is thus not recommended for + * any sort of common-case code. + * + * Note that it is illegal to call this function while holding any + * lock that is acquired by a CPU-hotplug notifier. Failing to + * observe this restriction will result in deadlock. + * + * This implementation can be thought of as an application of ticket + * locking to RCU, with sync_sched_expedited_started and + * sync_sched_expedited_done taking on the roles of the halves + * of the ticket-lock word. Each task atomically increments + * sync_sched_expedited_started upon entry, snapshotting the old value, + * then attempts to stop all the CPUs. If this succeeds, then each + * CPU will have executed a context switch, resulting in an RCU-sched + * grace period. We are then done, so we use atomic_cmpxchg() to + * update sync_sched_expedited_done to match our snapshot -- but + * only if someone else has not already advanced past our snapshot. + * + * On the other hand, if try_stop_cpus() fails, we check the value + * of sync_sched_expedited_done. If it has advanced past our + * initial snapshot, then someone else must have forced a grace period + * some time after we took our snapshot. In this case, our work is + * done for us, and we can simply return. Otherwise, we try again, + * but keep our initial snapshot for purposes of checking for someone + * doing our work for us. + * + * If we fail too many times in a row, we fall back to synchronize_sched(). + */ +void synchronize_sched_expedited(void) +{ + int firstsnap, s, snap, trycount = 0; + + /* Note that atomic_inc_return() implies full memory barrier. */ + firstsnap = snap = atomic_inc_return(&sync_sched_expedited_started); + get_online_cpus(); + + /* + * Each pass through the following loop attempts to force a + * context switch on each CPU. + */ + while (try_stop_cpus(cpu_online_mask, + synchronize_sched_expedited_cpu_stop, + NULL) == -EAGAIN) { + put_online_cpus(); + + /* No joy, try again later. Or just synchronize_sched(). */ + if (trycount++ < 10) + udelay(trycount * num_online_cpus()); + else { + synchronize_sched(); + return; + } + + /* Check to see if someone else did our work for us. */ + s = atomic_read(&sync_sched_expedited_done); + if (UINT_CMP_GE((unsigned)s, (unsigned)firstsnap)) { + smp_mb(); /* ensure test happens before caller kfree */ + return; + } + + /* + * Refetching sync_sched_expedited_started allows later + * callers to piggyback on our grace period. We subtract + * 1 to get the same token that the last incrementer got. + * We retry after they started, so our grace period works + * for them, and they started after our first try, so their + * grace period works for us. + */ + get_online_cpus(); + snap = atomic_read(&sync_sched_expedited_started) - 1; + smp_mb(); /* ensure read is before try_stop_cpus(). */ + } + + /* + * Everyone up to our most recent fetch is covered by our grace + * period. Update the counter, but only if our work is still + * relevant -- which it won't be if someone who started later + * than we did beat us to the punch. + */ + do { + s = atomic_read(&sync_sched_expedited_done); + if (UINT_CMP_GE((unsigned)s, (unsigned)snap)) { + smp_mb(); /* ensure test happens before caller kfree */ + break; + } + } while (atomic_cmpxchg(&sync_sched_expedited_done, s, snap) != s); + + put_online_cpus(); +} +EXPORT_SYMBOL_GPL(synchronize_sched_expedited); + +#endif /* #else #ifndef CONFIG_SMP */ + #if !defined(CONFIG_RCU_FAST_NO_HZ) /* @@ -1060,8 +1513,8 @@ static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff); * * Because it is not legal to invoke rcu_process_callbacks() with irqs * disabled, we do one pass of force_quiescent_state(), then do a - * raise_softirq() to cause rcu_process_callbacks() to be invoked later. - * The per-cpu rcu_dyntick_drain variable controls the sequencing. + * invoke_rcu_cpu_kthread() to cause rcu_process_callbacks() to be invoked + * later. The per-cpu rcu_dyntick_drain variable controls the sequencing. */ int rcu_needs_cpu(int cpu) { @@ -1112,7 +1565,7 @@ int rcu_needs_cpu(int cpu) /* If RCU callbacks are still pending, RCU still needs this CPU. */ if (c) - raise_softirq(RCU_SOFTIRQ); + invoke_rcu_cpu_kthread(); return c; } diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c index d15430b9d12..aa0fd72b4bc 100644 --- a/kernel/rcutree_trace.c +++ b/kernel/rcutree_trace.c @@ -46,6 +46,18 @@ #define RCU_TREE_NONCORE #include "rcutree.h" +DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status); +DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu); +DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); +DECLARE_PER_CPU(char, rcu_cpu_has_work); + +static char convert_kthread_status(unsigned int kthread_status) +{ + if (kthread_status > RCU_KTHREAD_MAX) + return '?'; + return "SRWOY"[kthread_status]; +} + static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) { if (!rdp->beenonline) @@ -64,7 +76,21 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) rdp->dynticks_fqs); #endif /* #ifdef CONFIG_NO_HZ */ seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi); - seq_printf(m, " ql=%ld b=%ld", rdp->qlen, rdp->blimit); + seq_printf(m, " ql=%ld qs=%c%c%c%c kt=%d/%c/%d ktl=%x b=%ld", + rdp->qlen, + ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] != + rdp->nxttail[RCU_NEXT_TAIL]], + ".R"[rdp->nxttail[RCU_WAIT_TAIL] != + rdp->nxttail[RCU_NEXT_READY_TAIL]], + ".W"[rdp->nxttail[RCU_DONE_TAIL] != + rdp->nxttail[RCU_WAIT_TAIL]], + ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]], + per_cpu(rcu_cpu_has_work, rdp->cpu), + convert_kthread_status(per_cpu(rcu_cpu_kthread_status, + rdp->cpu)), + per_cpu(rcu_cpu_kthread_cpu, rdp->cpu), + per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff, + rdp->blimit); seq_printf(m, " ci=%lu co=%lu ca=%lu\n", rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted); } @@ -121,7 +147,18 @@ static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp) rdp->dynticks_fqs); #endif /* #ifdef CONFIG_NO_HZ */ seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi); - seq_printf(m, ",%ld,%ld", rdp->qlen, rdp->blimit); + seq_printf(m, ",%ld,\"%c%c%c%c\",%d,\"%c\",%ld", rdp->qlen, + ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] != + rdp->nxttail[RCU_NEXT_TAIL]], + ".R"[rdp->nxttail[RCU_WAIT_TAIL] != + rdp->nxttail[RCU_NEXT_READY_TAIL]], + ".W"[rdp->nxttail[RCU_DONE_TAIL] != + rdp->nxttail[RCU_WAIT_TAIL]], + ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]], + per_cpu(rcu_cpu_has_work, rdp->cpu), + convert_kthread_status(per_cpu(rcu_cpu_kthread_status, + rdp->cpu)), + rdp->blimit); seq_printf(m, ",%lu,%lu,%lu\n", rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted); } @@ -157,34 +194,97 @@ static const struct file_operations rcudata_csv_fops = { .release = single_release, }; +#ifdef CONFIG_RCU_BOOST + +static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp) +{ + seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu " + "j=%04x bt=%04x\n", + rnp->grplo, rnp->grphi, + "T."[list_empty(&rnp->blkd_tasks)], + "N."[!rnp->gp_tasks], + "E."[!rnp->exp_tasks], + "B."[!rnp->boost_tasks], + convert_kthread_status(rnp->boost_kthread_status), + rnp->n_tasks_boosted, rnp->n_exp_boosts, + rnp->n_normal_boosts, + (int)(jiffies & 0xffff), + (int)(rnp->boost_time & 0xffff)); + seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n", + " balk", + rnp->n_balk_blkd_tasks, + rnp->n_balk_exp_gp_tasks, + rnp->n_balk_boost_tasks, + rnp->n_balk_notblocked, + rnp->n_balk_notyet, + rnp->n_balk_nos); +} + +static int show_rcu_node_boost(struct seq_file *m, void *unused) +{ + struct rcu_node *rnp; + + rcu_for_each_leaf_node(&rcu_preempt_state, rnp) + print_one_rcu_node_boost(m, rnp); + return 0; +} + +static int rcu_node_boost_open(struct inode *inode, struct file *file) +{ + return single_open(file, show_rcu_node_boost, NULL); +} + +static const struct file_operations rcu_node_boost_fops = { + .owner = THIS_MODULE, + .open = rcu_node_boost_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/* + * Create the rcuboost debugfs entry. Standard error return. + */ +static int rcu_boost_trace_create_file(struct dentry *rcudir) +{ + return !debugfs_create_file("rcuboost", 0444, rcudir, NULL, + &rcu_node_boost_fops); +} + +#else /* #ifdef CONFIG_RCU_BOOST */ + +static int rcu_boost_trace_create_file(struct dentry *rcudir) +{ + return 0; /* There cannot be an error if we didn't create it! */ +} + +#endif /* #else #ifdef CONFIG_RCU_BOOST */ + static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) { unsigned long gpnum; int level = 0; - int phase; struct rcu_node *rnp; gpnum = rsp->gpnum; seq_printf(m, "c=%lu g=%lu s=%d jfq=%ld j=%x " - "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld\n", + "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n", rsp->completed, gpnum, rsp->signaled, (long)(rsp->jiffies_force_qs - jiffies), (int)(jiffies & 0xffff), rsp->n_force_qs, rsp->n_force_qs_ngp, rsp->n_force_qs - rsp->n_force_qs_ngp, - rsp->n_force_qs_lh, rsp->orphan_qlen); + rsp->n_force_qs_lh); for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) { if (rnp->level != level) { seq_puts(m, "\n"); level = rnp->level; } - phase = gpnum & 0x1; - seq_printf(m, "%lx/%lx %c%c>%c%c %d:%d ^%d ", + seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d ", rnp->qsmask, rnp->qsmaskinit, - "T."[list_empty(&rnp->blocked_tasks[phase])], - "E."[list_empty(&rnp->blocked_tasks[phase + 2])], - "T."[list_empty(&rnp->blocked_tasks[!phase])], - "E."[list_empty(&rnp->blocked_tasks[!phase + 2])], + ".G"[rnp->gp_tasks != NULL], + ".E"[rnp->exp_tasks != NULL], + ".T"[!list_empty(&rnp->blkd_tasks)], rnp->grplo, rnp->grphi, rnp->grpnum); } seq_puts(m, "\n"); @@ -216,16 +316,35 @@ static const struct file_operations rcuhier_fops = { .release = single_release, }; +static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp) +{ + unsigned long flags; + unsigned long completed; + unsigned long gpnum; + unsigned long gpage; + unsigned long gpmax; + struct rcu_node *rnp = &rsp->node[0]; + + raw_spin_lock_irqsave(&rnp->lock, flags); + completed = rsp->completed; + gpnum = rsp->gpnum; + if (rsp->completed == rsp->gpnum) + gpage = 0; + else + gpage = jiffies - rsp->gp_start; + gpmax = rsp->gp_max; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + seq_printf(m, "%s: completed=%ld gpnum=%lu age=%ld max=%ld\n", + rsp->name, completed, gpnum, gpage, gpmax); +} + static int show_rcugp(struct seq_file *m, void *unused) { #ifdef CONFIG_TREE_PREEMPT_RCU - seq_printf(m, "rcu_preempt: completed=%ld gpnum=%lu\n", - rcu_preempt_state.completed, rcu_preempt_state.gpnum); + show_one_rcugp(m, &rcu_preempt_state); #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ - seq_printf(m, "rcu_sched: completed=%ld gpnum=%lu\n", - rcu_sched_state.completed, rcu_sched_state.gpnum); - seq_printf(m, "rcu_bh: completed=%ld gpnum=%lu\n", - rcu_bh_state.completed, rcu_bh_state.gpnum); + show_one_rcugp(m, &rcu_sched_state); + show_one_rcugp(m, &rcu_bh_state); return 0; } @@ -298,9 +417,32 @@ static const struct file_operations rcu_pending_fops = { .release = single_release, }; +static int show_rcutorture(struct seq_file *m, void *unused) +{ + seq_printf(m, "rcutorture test sequence: %lu %s\n", + rcutorture_testseq >> 1, + (rcutorture_testseq & 0x1) ? "(test in progress)" : ""); + seq_printf(m, "rcutorture update version number: %lu\n", + rcutorture_vernum); + return 0; +} + +static int rcutorture_open(struct inode *inode, struct file *file) +{ + return single_open(file, show_rcutorture, NULL); +} + +static const struct file_operations rcutorture_fops = { + .owner = THIS_MODULE, + .open = rcutorture_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + static struct dentry *rcudir; -static int __init rcuclassic_trace_init(void) +static int __init rcutree_trace_init(void) { struct dentry *retval; @@ -318,6 +460,9 @@ static int __init rcuclassic_trace_init(void) if (!retval) goto free_out; + if (rcu_boost_trace_create_file(rcudir)) + goto free_out; + retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops); if (!retval) goto free_out; @@ -331,20 +476,25 @@ static int __init rcuclassic_trace_init(void) NULL, &rcu_pending_fops); if (!retval) goto free_out; + + retval = debugfs_create_file("rcutorture", 0444, rcudir, + NULL, &rcutorture_fops); + if (!retval) + goto free_out; return 0; free_out: debugfs_remove_recursive(rcudir); return 1; } -static void __exit rcuclassic_trace_cleanup(void) +static void __exit rcutree_trace_cleanup(void) { debugfs_remove_recursive(rcudir); } -module_init(rcuclassic_trace_init); -module_exit(rcuclassic_trace_cleanup); +module_init(rcutree_trace_init); +module_exit(rcutree_trace_cleanup); MODULE_AUTHOR("Paul E. McKenney"); MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation"); diff --git a/kernel/relay.c b/kernel/relay.c index c7cf397fb92..859ea5a9605 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -70,17 +70,10 @@ static const struct vm_operations_struct relay_file_mmap_ops = { */ static struct page **relay_alloc_page_array(unsigned int n_pages) { - struct page **array; - size_t pa_size = n_pages * sizeof(struct page *); - - if (pa_size > PAGE_SIZE) { - array = vmalloc(pa_size); - if (array) - memset(array, 0, pa_size); - } else { - array = kzalloc(pa_size, GFP_KERNEL); - } - return array; + const size_t pa_size = n_pages * sizeof(struct page *); + if (pa_size > PAGE_SIZE) + return vzalloc(pa_size); + return kzalloc(pa_size, GFP_KERNEL); } /* diff --git a/kernel/res_counter.c b/kernel/res_counter.c index c7eaa37a768..34683efa2cc 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -126,10 +126,24 @@ ssize_t res_counter_read(struct res_counter *counter, int member, pos, buf, s - buf); } +#if BITS_PER_LONG == 32 +u64 res_counter_read_u64(struct res_counter *counter, int member) +{ + unsigned long flags; + u64 ret; + + spin_lock_irqsave(&counter->lock, flags); + ret = *res_counter_member(counter, member); + spin_unlock_irqrestore(&counter->lock, flags); + + return ret; +} +#else u64 res_counter_read_u64(struct res_counter *counter, int member) { return *res_counter_member(counter, member); } +#endif int res_counter_memparse_write_strategy(const char *buf, unsigned long long *res) diff --git a/kernel/resource.c b/kernel/resource.c index 9fad33efd0d..798e2fae2a0 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -40,23 +40,6 @@ EXPORT_SYMBOL(iomem_resource); static DEFINE_RWLOCK(resource_lock); -/* - * By default, we allocate free space bottom-up. The architecture can request - * top-down by clearing this flag. The user can override the architecture's - * choice with the "resource_alloc_from_bottom" kernel boot option, but that - * should only be a debugging tool. - */ -int resource_alloc_from_bottom = 1; - -static __init int setup_alloc_from_bottom(char *s) -{ - printk(KERN_INFO - "resource: allocating from bottom-up; please report a bug\n"); - resource_alloc_from_bottom = 1; - return 0; -} -early_param("resource_alloc_from_bottom", setup_alloc_from_bottom); - static void *r_next(struct seq_file *m, void *v, loff_t *pos) { struct resource *p = v; @@ -374,6 +357,10 @@ int __weak page_is_ram(unsigned long pfn) return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; } +void __weak arch_remove_reservations(struct resource *avail) +{ +} + static resource_size_t simple_align_resource(void *data, const struct resource *avail, resource_size_t size, @@ -397,74 +384,7 @@ static bool resource_contains(struct resource *res1, struct resource *res2) } /* - * Find the resource before "child" in the sibling list of "root" children. - */ -static struct resource *find_sibling_prev(struct resource *root, struct resource *child) -{ - struct resource *this; - - for (this = root->child; this; this = this->sibling) - if (this->sibling == child) - return this; - - return NULL; -} - -/* * Find empty slot in the resource tree given range and alignment. - * This version allocates from the end of the root resource first. - */ -static int find_resource_from_top(struct resource *root, struct resource *new, - resource_size_t size, resource_size_t min, - resource_size_t max, resource_size_t align, - resource_size_t (*alignf)(void *, - const struct resource *, - resource_size_t, - resource_size_t), - void *alignf_data) -{ - struct resource *this; - struct resource tmp, avail, alloc; - - tmp.start = root->end; - tmp.end = root->end; - - this = find_sibling_prev(root, NULL); - for (;;) { - if (this) { - if (this->end < root->end) - tmp.start = this->end + 1; - } else - tmp.start = root->start; - - resource_clip(&tmp, min, max); - - /* Check for overflow after ALIGN() */ - avail = *new; - avail.start = ALIGN(tmp.start, align); - avail.end = tmp.end; - if (avail.start >= tmp.start) { - alloc.start = alignf(alignf_data, &avail, size, align); - alloc.end = alloc.start + size - 1; - if (resource_contains(&avail, &alloc)) { - new->start = alloc.start; - new->end = alloc.end; - return 0; - } - } - - if (!this || this->start == root->start) - break; - - tmp.end = this->start - 1; - this = find_sibling_prev(root, this); - } - return -EBUSY; -} - -/* - * Find empty slot in the resource tree given range and alignment. - * This version allocates from the beginning of the root resource first. */ static int find_resource(struct resource *root, struct resource *new, resource_size_t size, resource_size_t min, @@ -478,23 +398,24 @@ static int find_resource(struct resource *root, struct resource *new, struct resource *this = root->child; struct resource tmp = *new, avail, alloc; + tmp.flags = new->flags; tmp.start = root->start; /* - * Skip past an allocated resource that starts at 0, since the - * assignment of this->start - 1 to tmp->end below would cause an - * underflow. + * Skip past an allocated resource that starts at 0, since the assignment + * of this->start - 1 to tmp->end below would cause an underflow. */ if (this && this->start == 0) { tmp.start = this->end + 1; this = this->sibling; } - for (;;) { + for(;;) { if (this) tmp.end = this->start - 1; else tmp.end = root->end; resource_clip(&tmp, min, max); + arch_remove_reservations(&tmp); /* Check for overflow after ALIGN() */ avail = *new; @@ -509,10 +430,8 @@ static int find_resource(struct resource *root, struct resource *new, return 0; } } - if (!this) break; - tmp.start = this->end + 1; this = this->sibling; } @@ -545,10 +464,7 @@ int allocate_resource(struct resource *root, struct resource *new, alignf = simple_align_resource; write_lock(&resource_lock); - if (resource_alloc_from_bottom) - err = find_resource(root, new, size, min, max, align, alignf, alignf_data); - else - err = find_resource_from_top(root, new, size, min, max, align, alignf, alignf_data); + err = find_resource(root, new, size, min, max, align, alignf, alignf_data); if (err >= 0 && __request_resource(root, new)) err = -EBUSY; write_unlock(&resource_lock); diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c index ddabb54bb5c..3c7cbc2c33b 100644 --- a/kernel/rtmutex-debug.c +++ b/kernel/rtmutex-debug.c @@ -215,7 +215,6 @@ void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter) put_pid(waiter->deadlock_task_pid); TRACE_WARN_ON(!plist_node_empty(&waiter->list_entry)); TRACE_WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); - TRACE_WARN_ON(waiter->task); memset(waiter, 0x22, sizeof(*waiter)); } diff --git a/kernel/rtmutex-tester.c b/kernel/rtmutex-tester.c index 66cb89bc5ef..5c9ccd38096 100644 --- a/kernel/rtmutex-tester.c +++ b/kernel/rtmutex-tester.c @@ -9,7 +9,6 @@ #include <linux/kthread.h> #include <linux/module.h> #include <linux/sched.h> -#include <linux/smp_lock.h> #include <linux/spinlock.h> #include <linux/sysdev.h> #include <linux/timer.h> @@ -27,7 +26,6 @@ struct test_thread_data { int opcode; int opdata; int mutexes[MAX_RT_TEST_MUTEXES]; - int bkl; int event; struct sys_device sysdev; }; @@ -46,9 +44,8 @@ enum test_opcodes { RTTEST_LOCKINTNOWAIT, /* 6 Lock interruptible no wait in wakeup, data = lockindex */ RTTEST_LOCKCONT, /* 7 Continue locking after the wakeup delay */ RTTEST_UNLOCK, /* 8 Unlock, data = lockindex */ - RTTEST_LOCKBKL, /* 9 Lock BKL */ - RTTEST_UNLOCKBKL, /* 10 Unlock BKL */ - RTTEST_SIGNAL, /* 11 Signal other test thread, data = thread id */ + /* 9, 10 - reserved for BKL commemoration */ + RTTEST_SIGNAL = 11, /* 11 Signal other test thread, data = thread id */ RTTEST_RESETEVENT = 98, /* 98 Reset event counter */ RTTEST_RESET = 99, /* 99 Reset all pending operations */ }; @@ -74,13 +71,6 @@ static int handle_op(struct test_thread_data *td, int lockwakeup) td->mutexes[i] = 0; } } - - if (!lockwakeup && td->bkl == 4) { -#ifdef CONFIG_LOCK_KERNEL - unlock_kernel(); -#endif - td->bkl = 0; - } return 0; case RTTEST_RESETEVENT: @@ -131,25 +121,6 @@ static int handle_op(struct test_thread_data *td, int lockwakeup) td->mutexes[id] = 0; return 0; - case RTTEST_LOCKBKL: - if (td->bkl) - return 0; - td->bkl = 1; -#ifdef CONFIG_LOCK_KERNEL - lock_kernel(); -#endif - td->bkl = 4; - return 0; - - case RTTEST_UNLOCKBKL: - if (td->bkl != 4) - break; -#ifdef CONFIG_LOCK_KERNEL - unlock_kernel(); -#endif - td->bkl = 0; - return 0; - default: break; } @@ -196,7 +167,6 @@ void schedule_rt_mutex_test(struct rt_mutex *mutex) td->event = atomic_add_return(1, &rttest_event); break; - case RTTEST_LOCKBKL: default: break; } @@ -229,8 +199,6 @@ void schedule_rt_mutex_test(struct rt_mutex *mutex) td->event = atomic_add_return(1, &rttest_event); return; - case RTTEST_LOCKBKL: - return; default: return; } @@ -380,11 +348,11 @@ static ssize_t sysfs_test_status(struct sys_device *dev, struct sysdev_attribute spin_lock(&rttest_lock); curr += sprintf(curr, - "O: %4d, E:%8d, S: 0x%08lx, P: %4d, N: %4d, B: %p, K: %d, M:", + "O: %4d, E:%8d, S: 0x%08lx, P: %4d, N: %4d, B: %p, M:", td->opcode, td->event, tsk->state, (MAX_RT_PRIO - 1) - tsk->prio, (MAX_RT_PRIO - 1) - tsk->normal_prio, - tsk->pi_blocked_on, td->bkl); + tsk->pi_blocked_on); for (i = MAX_RT_TEST_MUTEXES - 1; i >=0 ; i--) curr += sprintf(curr, "%d", td->mutexes[i]); diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c index a9604815786..ab449117aaf 100644 --- a/kernel/rtmutex.c +++ b/kernel/rtmutex.c @@ -20,41 +20,34 @@ /* * lock->owner state tracking: * - * lock->owner holds the task_struct pointer of the owner. Bit 0 and 1 - * are used to keep track of the "owner is pending" and "lock has - * waiters" state. + * lock->owner holds the task_struct pointer of the owner. Bit 0 + * is used to keep track of the "lock has waiters" state. * - * owner bit1 bit0 - * NULL 0 0 lock is free (fast acquire possible) - * NULL 0 1 invalid state - * NULL 1 0 Transitional State* - * NULL 1 1 invalid state - * taskpointer 0 0 lock is held (fast release possible) - * taskpointer 0 1 task is pending owner - * taskpointer 1 0 lock is held and has waiters - * taskpointer 1 1 task is pending owner and lock has more waiters - * - * Pending ownership is assigned to the top (highest priority) - * waiter of the lock, when the lock is released. The thread is woken - * up and can now take the lock. Until the lock is taken (bit 0 - * cleared) a competing higher priority thread can steal the lock - * which puts the woken up thread back on the waiters list. + * owner bit0 + * NULL 0 lock is free (fast acquire possible) + * NULL 1 lock is free and has waiters and the top waiter + * is going to take the lock* + * taskpointer 0 lock is held (fast release possible) + * taskpointer 1 lock is held and has waiters** * * The fast atomic compare exchange based acquire and release is only - * possible when bit 0 and 1 of lock->owner are 0. + * possible when bit 0 of lock->owner is 0. + * + * (*) It also can be a transitional state when grabbing the lock + * with ->wait_lock is held. To prevent any fast path cmpxchg to the lock, + * we need to set the bit0 before looking at the lock, and the owner may be + * NULL in this small time, hence this can be a transitional state. * - * (*) There's a small time where the owner can be NULL and the - * "lock has waiters" bit is set. This can happen when grabbing the lock. - * To prevent a cmpxchg of the owner releasing the lock, we need to set this - * bit before looking at the lock, hence the reason this is a transitional - * state. + * (**) There is a small time when bit 0 is set but there are no + * waiters. This can happen when grabbing the lock in the slow path. + * To prevent a cmpxchg of the owner releasing the lock, we need to + * set this bit before looking at the lock. */ static void -rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner, - unsigned long mask) +rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner) { - unsigned long val = (unsigned long)owner | mask; + unsigned long val = (unsigned long)owner; if (rt_mutex_has_waiters(lock)) val |= RT_MUTEX_HAS_WAITERS; @@ -203,15 +196,14 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, * reached or the state of the chain has changed while we * dropped the locks. */ - if (!waiter || !waiter->task) + if (!waiter) goto out_unlock_pi; /* * Check the orig_waiter state. After we dropped the locks, - * the previous owner of the lock might have released the lock - * and made us the pending owner: + * the previous owner of the lock might have released the lock. */ - if (orig_waiter && !orig_waiter->task) + if (orig_waiter && !rt_mutex_owner(orig_lock)) goto out_unlock_pi; /* @@ -254,6 +246,17 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, /* Release the task */ raw_spin_unlock_irqrestore(&task->pi_lock, flags); + if (!rt_mutex_owner(lock)) { + /* + * If the requeue above changed the top waiter, then we need + * to wake the new top waiter up to try to get the lock. + */ + + if (top_waiter != rt_mutex_top_waiter(lock)) + wake_up_process(rt_mutex_top_waiter(lock)->task); + raw_spin_unlock(&lock->wait_lock); + goto out_put_task; + } put_task_struct(task); /* Grab the next task */ @@ -296,78 +299,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, } /* - * Optimization: check if we can steal the lock from the - * assigned pending owner [which might not have taken the - * lock yet]: - */ -static inline int try_to_steal_lock(struct rt_mutex *lock, - struct task_struct *task) -{ - struct task_struct *pendowner = rt_mutex_owner(lock); - struct rt_mutex_waiter *next; - unsigned long flags; - - if (!rt_mutex_owner_pending(lock)) - return 0; - - if (pendowner == task) - return 1; - - raw_spin_lock_irqsave(&pendowner->pi_lock, flags); - if (task->prio >= pendowner->prio) { - raw_spin_unlock_irqrestore(&pendowner->pi_lock, flags); - return 0; - } - - /* - * Check if a waiter is enqueued on the pending owners - * pi_waiters list. Remove it and readjust pending owners - * priority. - */ - if (likely(!rt_mutex_has_waiters(lock))) { - raw_spin_unlock_irqrestore(&pendowner->pi_lock, flags); - return 1; - } - - /* No chain handling, pending owner is not blocked on anything: */ - next = rt_mutex_top_waiter(lock); - plist_del(&next->pi_list_entry, &pendowner->pi_waiters); - __rt_mutex_adjust_prio(pendowner); - raw_spin_unlock_irqrestore(&pendowner->pi_lock, flags); - - /* - * We are going to steal the lock and a waiter was - * enqueued on the pending owners pi_waiters queue. So - * we have to enqueue this waiter into - * task->pi_waiters list. This covers the case, - * where task is boosted because it holds another - * lock and gets unboosted because the booster is - * interrupted, so we would delay a waiter with higher - * priority as task->normal_prio. - * - * Note: in the rare case of a SCHED_OTHER task changing - * its priority and thus stealing the lock, next->task - * might be task: - */ - if (likely(next->task != task)) { - raw_spin_lock_irqsave(&task->pi_lock, flags); - plist_add(&next->pi_list_entry, &task->pi_waiters); - __rt_mutex_adjust_prio(task); - raw_spin_unlock_irqrestore(&task->pi_lock, flags); - } - return 1; -} - -/* * Try to take an rt-mutex * - * This fails - * - when the lock has a real owner - * - when a different pending owner exists and has higher priority than current - * * Must be called with lock->wait_lock held. + * + * @lock: the lock to be acquired. + * @task: the task which wants to acquire the lock + * @waiter: the waiter that is queued to the lock's wait list. (could be NULL) */ -static int try_to_take_rt_mutex(struct rt_mutex *lock) +static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, + struct rt_mutex_waiter *waiter) { /* * We have to be careful here if the atomic speedups are @@ -390,15 +331,52 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock) */ mark_rt_mutex_waiters(lock); - if (rt_mutex_owner(lock) && !try_to_steal_lock(lock, current)) + if (rt_mutex_owner(lock)) return 0; + /* + * It will get the lock because of one of these conditions: + * 1) there is no waiter + * 2) higher priority than waiters + * 3) it is top waiter + */ + if (rt_mutex_has_waiters(lock)) { + if (task->prio >= rt_mutex_top_waiter(lock)->list_entry.prio) { + if (!waiter || waiter != rt_mutex_top_waiter(lock)) + return 0; + } + } + + if (waiter || rt_mutex_has_waiters(lock)) { + unsigned long flags; + struct rt_mutex_waiter *top; + + raw_spin_lock_irqsave(&task->pi_lock, flags); + + /* remove the queued waiter. */ + if (waiter) { + plist_del(&waiter->list_entry, &lock->wait_list); + task->pi_blocked_on = NULL; + } + + /* + * We have to enqueue the top waiter(if it exists) into + * task->pi_waiters list. + */ + if (rt_mutex_has_waiters(lock)) { + top = rt_mutex_top_waiter(lock); + top->pi_list_entry.prio = top->list_entry.prio; + plist_add(&top->pi_list_entry, &task->pi_waiters); + } + raw_spin_unlock_irqrestore(&task->pi_lock, flags); + } + /* We got the lock. */ debug_rt_mutex_lock(lock); - rt_mutex_set_owner(lock, current, 0); + rt_mutex_set_owner(lock, task); - rt_mutex_deadlock_account_lock(lock, current); + rt_mutex_deadlock_account_lock(lock, task); return 1; } @@ -436,6 +414,9 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, raw_spin_unlock_irqrestore(&task->pi_lock, flags); + if (!owner) + return 0; + if (waiter == rt_mutex_top_waiter(lock)) { raw_spin_lock_irqsave(&owner->pi_lock, flags); plist_del(&top_waiter->pi_list_entry, &owner->pi_waiters); @@ -472,21 +453,18 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, /* * Wake up the next waiter on the lock. * - * Remove the top waiter from the current tasks waiter list and from - * the lock waiter list. Set it as pending owner. Then wake it up. + * Remove the top waiter from the current tasks waiter list and wake it up. * * Called with lock->wait_lock held. */ static void wakeup_next_waiter(struct rt_mutex *lock) { struct rt_mutex_waiter *waiter; - struct task_struct *pendowner; unsigned long flags; raw_spin_lock_irqsave(¤t->pi_lock, flags); waiter = rt_mutex_top_waiter(lock); - plist_del(&waiter->list_entry, &lock->wait_list); /* * Remove it from current->pi_waiters. We do not adjust a @@ -495,43 +473,19 @@ static void wakeup_next_waiter(struct rt_mutex *lock) * lock->wait_lock. */ plist_del(&waiter->pi_list_entry, ¤t->pi_waiters); - pendowner = waiter->task; - waiter->task = NULL; - rt_mutex_set_owner(lock, pendowner, RT_MUTEX_OWNER_PENDING); + rt_mutex_set_owner(lock, NULL); raw_spin_unlock_irqrestore(¤t->pi_lock, flags); - /* - * Clear the pi_blocked_on variable and enqueue a possible - * waiter into the pi_waiters list of the pending owner. This - * prevents that in case the pending owner gets unboosted a - * waiter with higher priority than pending-owner->normal_prio - * is blocked on the unboosted (pending) owner. - */ - raw_spin_lock_irqsave(&pendowner->pi_lock, flags); - - WARN_ON(!pendowner->pi_blocked_on); - WARN_ON(pendowner->pi_blocked_on != waiter); - WARN_ON(pendowner->pi_blocked_on->lock != lock); - - pendowner->pi_blocked_on = NULL; - - if (rt_mutex_has_waiters(lock)) { - struct rt_mutex_waiter *next; - - next = rt_mutex_top_waiter(lock); - plist_add(&next->pi_list_entry, &pendowner->pi_waiters); - } - raw_spin_unlock_irqrestore(&pendowner->pi_lock, flags); - - wake_up_process(pendowner); + wake_up_process(waiter->task); } /* - * Remove a waiter from a lock + * Remove a waiter from a lock and give up * - * Must be called with lock->wait_lock held + * Must be called with lock->wait_lock held and + * have just failed to try_to_take_rt_mutex(). */ static void remove_waiter(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) @@ -543,11 +497,13 @@ static void remove_waiter(struct rt_mutex *lock, raw_spin_lock_irqsave(¤t->pi_lock, flags); plist_del(&waiter->list_entry, &lock->wait_list); - waiter->task = NULL; current->pi_blocked_on = NULL; raw_spin_unlock_irqrestore(¤t->pi_lock, flags); - if (first && owner != current) { + if (!owner) + return; + + if (first) { raw_spin_lock_irqsave(&owner->pi_lock, flags); @@ -614,21 +570,19 @@ void rt_mutex_adjust_pi(struct task_struct *task) * or TASK_UNINTERRUPTIBLE) * @timeout: the pre-initialized and started timer, or NULL for none * @waiter: the pre-initialized rt_mutex_waiter - * @detect_deadlock: passed to task_blocks_on_rt_mutex * * lock->wait_lock must be held by the caller. */ static int __sched __rt_mutex_slowlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - struct rt_mutex_waiter *waiter, - int detect_deadlock) + struct rt_mutex_waiter *waiter) { int ret = 0; for (;;) { /* Try to acquire the lock: */ - if (try_to_take_rt_mutex(lock)) + if (try_to_take_rt_mutex(lock, current, waiter)) break; /* @@ -645,39 +599,11 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state, break; } - /* - * waiter->task is NULL the first time we come here and - * when we have been woken up by the previous owner - * but the lock got stolen by a higher prio task. - */ - if (!waiter->task) { - ret = task_blocks_on_rt_mutex(lock, waiter, current, - detect_deadlock); - /* - * If we got woken up by the owner then start loop - * all over without going into schedule to try - * to get the lock now: - */ - if (unlikely(!waiter->task)) { - /* - * Reset the return value. We might - * have returned with -EDEADLK and the - * owner released the lock while we - * were walking the pi chain. - */ - ret = 0; - continue; - } - if (unlikely(ret)) - break; - } - raw_spin_unlock(&lock->wait_lock); debug_rt_mutex_print_deadlock(waiter); - if (waiter->task) - schedule_rt_mutex(lock); + schedule_rt_mutex(lock); raw_spin_lock(&lock->wait_lock); set_current_state(state); @@ -698,12 +624,11 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, int ret = 0; debug_rt_mutex_init_waiter(&waiter); - waiter.task = NULL; raw_spin_lock(&lock->wait_lock); /* Try to acquire the lock again: */ - if (try_to_take_rt_mutex(lock)) { + if (try_to_take_rt_mutex(lock, current, NULL)) { raw_spin_unlock(&lock->wait_lock); return 0; } @@ -717,12 +642,14 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, timeout->task = NULL; } - ret = __rt_mutex_slowlock(lock, state, timeout, &waiter, - detect_deadlock); + ret = task_blocks_on_rt_mutex(lock, &waiter, current, detect_deadlock); + + if (likely(!ret)) + ret = __rt_mutex_slowlock(lock, state, timeout, &waiter); set_current_state(TASK_RUNNING); - if (unlikely(waiter.task)) + if (unlikely(ret)) remove_waiter(lock, &waiter); /* @@ -737,14 +664,6 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, if (unlikely(timeout)) hrtimer_cancel(&timeout->timer); - /* - * Readjust priority, when we did not get the lock. We might - * have been the pending owner and boosted. Since we did not - * take the lock, the PI boost has to go. - */ - if (unlikely(ret)) - rt_mutex_adjust_prio(current); - debug_rt_mutex_free_waiter(&waiter); return ret; @@ -762,7 +681,7 @@ rt_mutex_slowtrylock(struct rt_mutex *lock) if (likely(rt_mutex_owner(lock) != current)) { - ret = try_to_take_rt_mutex(lock); + ret = try_to_take_rt_mutex(lock, current, NULL); /* * try_to_take_rt_mutex() sets the lock waiters * bit unconditionally. Clean this up. @@ -992,7 +911,7 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock, { __rt_mutex_init(lock, NULL); debug_rt_mutex_proxy_lock(lock, proxy_owner); - rt_mutex_set_owner(lock, proxy_owner, 0); + rt_mutex_set_owner(lock, proxy_owner); rt_mutex_deadlock_account_lock(lock, proxy_owner); } @@ -1008,7 +927,7 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock, struct task_struct *proxy_owner) { debug_rt_mutex_proxy_unlock(lock); - rt_mutex_set_owner(lock, NULL, 0); + rt_mutex_set_owner(lock, NULL); rt_mutex_deadlock_account_unlock(proxy_owner); } @@ -1034,20 +953,14 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock, raw_spin_lock(&lock->wait_lock); - mark_rt_mutex_waiters(lock); - - if (!rt_mutex_owner(lock) || try_to_steal_lock(lock, task)) { - /* We got the lock for task. */ - debug_rt_mutex_lock(lock); - rt_mutex_set_owner(lock, task, 0); + if (try_to_take_rt_mutex(lock, task, NULL)) { raw_spin_unlock(&lock->wait_lock); - rt_mutex_deadlock_account_lock(lock, task); return 1; } ret = task_blocks_on_rt_mutex(lock, waiter, task, detect_deadlock); - if (ret && !waiter->task) { + if (ret && !rt_mutex_owner(lock)) { /* * Reset the return value. We might have * returned with -EDEADLK and the owner @@ -1056,6 +969,10 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock, */ ret = 0; } + + if (unlikely(ret)) + remove_waiter(lock, waiter); + raw_spin_unlock(&lock->wait_lock); debug_rt_mutex_print_deadlock(waiter); @@ -1110,12 +1027,11 @@ int rt_mutex_finish_proxy_lock(struct rt_mutex *lock, set_current_state(TASK_INTERRUPTIBLE); - ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, - detect_deadlock); + ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter); set_current_state(TASK_RUNNING); - if (unlikely(waiter->task)) + if (unlikely(ret)) remove_waiter(lock, waiter); /* @@ -1126,13 +1042,5 @@ int rt_mutex_finish_proxy_lock(struct rt_mutex *lock, raw_spin_unlock(&lock->wait_lock); - /* - * Readjust priority, when we did not get the lock. We might have been - * the pending owner and boosted. Since we did not take the lock, the - * PI boost has to go. - */ - if (unlikely(ret)) - rt_mutex_adjust_prio(current); - return ret; } diff --git a/kernel/rtmutex_common.h b/kernel/rtmutex_common.h index 97a2f81866a..53a66c85261 100644 --- a/kernel/rtmutex_common.h +++ b/kernel/rtmutex_common.h @@ -91,9 +91,8 @@ task_top_pi_waiter(struct task_struct *p) /* * lock->owner state tracking: */ -#define RT_MUTEX_OWNER_PENDING 1UL -#define RT_MUTEX_HAS_WAITERS 2UL -#define RT_MUTEX_OWNER_MASKALL 3UL +#define RT_MUTEX_HAS_WAITERS 1UL +#define RT_MUTEX_OWNER_MASKALL 1UL static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock) { @@ -101,17 +100,6 @@ static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock) ((unsigned long)lock->owner & ~RT_MUTEX_OWNER_MASKALL); } -static inline struct task_struct *rt_mutex_real_owner(struct rt_mutex *lock) -{ - return (struct task_struct *) - ((unsigned long)lock->owner & ~RT_MUTEX_HAS_WAITERS); -} - -static inline unsigned long rt_mutex_owner_pending(struct rt_mutex *lock) -{ - return (unsigned long)lock->owner & RT_MUTEX_OWNER_PENDING; -} - /* * PI-futex support (proxy locking functions, etc.): */ diff --git a/kernel/sched.c b/kernel/sched.c index aa14a56f9d0..c62acf45d3b 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -32,7 +32,6 @@ #include <linux/init.h> #include <linux/uaccess.h> #include <linux/highmem.h> -#include <linux/smp_lock.h> #include <asm/mmu_context.h> #include <linux/interrupt.h> #include <linux/capability.h> @@ -75,9 +74,11 @@ #include <asm/tlb.h> #include <asm/irq_regs.h> +#include <asm/mutex.h> #include "sched_cpupri.h" #include "workqueue_sched.h" +#include "sched_autogroup.h" #define CREATE_TRACE_POINTS #include <trace/events/sched.h> @@ -230,7 +231,7 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b) #endif /* - * sched_domains_mutex serializes calls to arch_init_sched_domains, + * sched_domains_mutex serializes calls to init_sched_domains, * detach_destroy_domains and partition_sched_domains. */ static DEFINE_MUTEX(sched_domains_mutex); @@ -253,6 +254,8 @@ struct task_group { /* runqueue "owned" by this group on each cpu */ struct cfs_rq **cfs_rq; unsigned long shares; + + atomic_t load_weight; #endif #ifdef CONFIG_RT_GROUP_SCHED @@ -268,25 +271,18 @@ struct task_group { struct task_group *parent; struct list_head siblings; struct list_head children; -}; -#define root_task_group init_task_group +#ifdef CONFIG_SCHED_AUTOGROUP + struct autogroup *autogroup; +#endif +}; -/* task_group_lock serializes add/remove of task groups and also changes to - * a task group's cpu shares. - */ +/* task_group_lock serializes the addition/removal of task groups */ static DEFINE_SPINLOCK(task_group_lock); #ifdef CONFIG_FAIR_GROUP_SCHED -#ifdef CONFIG_SMP -static int root_task_group_empty(void) -{ - return list_empty(&root_task_group.children); -} -#endif - -# define INIT_TASK_GROUP_LOAD NICE_0_LOAD +# define ROOT_TASK_GROUP_LOAD NICE_0_LOAD /* * A weight of 0 or 1 can cause arithmetics problems. @@ -299,13 +295,13 @@ static int root_task_group_empty(void) #define MIN_SHARES 2 #define MAX_SHARES (1UL << 18) -static int init_task_group_load = INIT_TASK_GROUP_LOAD; +static int root_task_group_load = ROOT_TASK_GROUP_LOAD; #endif /* Default task group. * Every task in system belong to this group at bootup. */ -struct task_group init_task_group; +struct task_group root_task_group; #endif /* CONFIG_CGROUP_SCHED */ @@ -316,6 +312,9 @@ struct cfs_rq { u64 exec_clock; u64 min_vruntime; +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; +#endif struct rb_root tasks_timeline; struct rb_node *rb_leftmost; @@ -327,9 +326,11 @@ struct cfs_rq { * 'curr' points to currently running entity on this cfs_rq. * It is set to NULL otherwise (i.e when none are currently running). */ - struct sched_entity *curr, *next, *last; + struct sched_entity *curr, *next, *last, *skip; +#ifdef CONFIG_SCHED_DEBUG unsigned int nr_spread_over; +#endif #ifdef CONFIG_FAIR_GROUP_SCHED struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ @@ -342,6 +343,7 @@ struct cfs_rq { * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This * list is used during load balance. */ + int on_list; struct list_head leaf_cfs_rq_list; struct task_group *tg; /* group that "owns" this runqueue */ @@ -360,14 +362,17 @@ struct cfs_rq { unsigned long h_load; /* - * this cpu's part of tg->shares + * Maintaining per-cpu shares distribution for group scheduling + * + * load_stamp is the last time we updated the load average + * load_last is the last time we updated the load average and saw load + * load_unacc_exec_time is currently unaccounted execution time */ - unsigned long shares; + u64 load_avg; + u64 load_period; + u64 load_stamp, load_last, load_unacc_exec_time; - /* - * load.weight at the time we set shares - */ - unsigned long rq_weight; + unsigned long load_contribution; #endif #endif }; @@ -417,6 +422,7 @@ struct rt_rq { */ struct root_domain { atomic_t refcount; + struct rcu_head rcu; cpumask_var_t span; cpumask_var_t online; @@ -460,7 +466,7 @@ struct rq { u64 nohz_stamp; unsigned char nohz_balance_kick; #endif - unsigned int skip_clock_update; + int skip_clock_update; /* capture load from *all* tasks on this cpu: */ struct load_weight load; @@ -552,26 +558,17 @@ struct rq { /* try_to_wake_up() stats */ unsigned int ttwu_count; unsigned int ttwu_local; +#endif - /* BKL stats */ - unsigned int bkl_count; +#ifdef CONFIG_SMP + struct task_struct *wake_list; #endif }; static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); -static inline -void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) -{ - rq->curr->sched_class->check_preempt_curr(rq, p, flags); - /* - * A queue event has occurred, and we're going to schedule. In - * this case, we can save a useless back to back clock update. - */ - if (test_tsk_need_resched(p)) - rq->skip_clock_update = 1; -} +static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); static inline int cpu_of(struct rq *rq) { @@ -584,7 +581,7 @@ static inline int cpu_of(struct rq *rq) #define rcu_dereference_check_sched_domain(p) \ rcu_dereference_check((p), \ - rcu_read_lock_sched_held() || \ + rcu_read_lock_held() || \ lockdep_is_held(&sched_domains_mutex)) /* @@ -609,17 +606,20 @@ static inline int cpu_of(struct rq *rq) * Return the group to which this tasks belongs. * * We use task_subsys_state_check() and extend the RCU verification - * with lockdep_is_held(&task_rq(p)->lock) because cpu_cgroup_attach() + * with lockdep_is_held(&p->pi_lock) because cpu_cgroup_attach() * holds that lock for each task it moves into the cgroup. Therefore * by holding that lock, we pin the task to the current cgroup. */ static inline struct task_group *task_group(struct task_struct *p) { + struct task_group *tg; struct cgroup_subsys_state *css; css = task_subsys_state_check(p, cpu_cgroup_subsys_id, - lockdep_is_held(&task_rq(p)->lock)); - return container_of(css, struct task_group, css); + lockdep_is_held(&p->pi_lock)); + tg = container_of(css, struct task_group, css); + + return autogroup_task_group(p, tg); } /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ @@ -646,22 +646,18 @@ static inline struct task_group *task_group(struct task_struct *p) #endif /* CONFIG_CGROUP_SCHED */ -static u64 irq_time_cpu(int cpu); -static void sched_irq_time_avg_update(struct rq *rq, u64 irq_time); +static void update_rq_clock_task(struct rq *rq, s64 delta); -inline void update_rq_clock(struct rq *rq) +static void update_rq_clock(struct rq *rq) { - if (!rq->skip_clock_update) { - int cpu = cpu_of(rq); - u64 irq_time; + s64 delta; - rq->clock = sched_clock_cpu(cpu); - irq_time = irq_time_cpu(cpu); - if (rq->clock - irq_time > rq->clock_task) - rq->clock_task = rq->clock - irq_time; + if (rq->skip_clock_update > 0) + return; - sched_irq_time_avg_update(rq, irq_time); - } + delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; + rq->clock += delta; + update_rq_clock_task(rq, delta); } /* @@ -674,10 +670,9 @@ inline void update_rq_clock(struct rq *rq) #endif /** - * runqueue_is_locked + * runqueue_is_locked - Returns true if the current cpu runqueue is locked * @cpu: the processor in question. * - * Returns true if the current cpu runqueue is locked. * This interface allows printk to be called with the runqueue lock * held and know whether or not it is OK to wake up the klogd. */ @@ -751,7 +746,7 @@ sched_feat_write(struct file *filp, const char __user *ubuf, buf[cnt] = 0; cmp = strstrip(buf); - if (strncmp(buf, "NO_", 3) == 0) { + if (strncmp(cmp, "NO_", 3) == 0) { neg = 1; cmp += 3; } @@ -807,20 +802,6 @@ late_initcall(sched_init_debug); const_debug unsigned int sysctl_sched_nr_migrate = 32; /* - * ratelimit for updating the group shares. - * default: 0.25ms - */ -unsigned int sysctl_sched_shares_ratelimit = 250000; -unsigned int normalized_sysctl_sched_shares_ratelimit = 250000; - -/* - * Inject some fuzzyness into changing the per-cpu group shares - * this avoids remote rq-locks at the expense of fairness. - * default: 4 - */ -unsigned int sysctl_sched_shares_thresh = 4; - -/* * period over which we average the RT time consumption, measured * in ms. * @@ -867,18 +848,39 @@ static inline int task_current(struct rq *rq, struct task_struct *p) return rq->curr == p; } -#ifndef __ARCH_WANT_UNLOCKED_CTXSW static inline int task_running(struct rq *rq, struct task_struct *p) { +#ifdef CONFIG_SMP + return p->on_cpu; +#else return task_current(rq, p); +#endif } +#ifndef __ARCH_WANT_UNLOCKED_CTXSW static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) { +#ifdef CONFIG_SMP + /* + * We can optimise this out completely for !SMP, because the + * SMP rebalancing from interrupt is the only thing that cares + * here. + */ + next->on_cpu = 1; +#endif } static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) { +#ifdef CONFIG_SMP + /* + * After ->on_cpu is cleared, the task can be moved to a different CPU. + * We must ensure this doesn't happen until the switch is completely + * finished. + */ + smp_wmb(); + prev->on_cpu = 0; +#endif #ifdef CONFIG_DEBUG_SPINLOCK /* this is a valid case when another task releases the spinlock */ rq->lock.owner = current; @@ -894,15 +896,6 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) } #else /* __ARCH_WANT_UNLOCKED_CTXSW */ -static inline int task_running(struct rq *rq, struct task_struct *p) -{ -#ifdef CONFIG_SMP - return p->oncpu; -#else - return task_current(rq, p); -#endif -} - static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) { #ifdef CONFIG_SMP @@ -911,7 +904,7 @@ static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) * SMP rebalancing from interrupt is the only thing that cares * here. */ - next->oncpu = 1; + next->on_cpu = 1; #endif #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW raw_spin_unlock_irq(&rq->lock); @@ -924,12 +917,12 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) { #ifdef CONFIG_SMP /* - * After ->oncpu is cleared, the task can be moved to a different CPU. + * After ->on_cpu is cleared, the task can be moved to a different CPU. * We must ensure this doesn't happen until the switch is completely * finished. */ smp_wmb(); - prev->oncpu = 0; + prev->on_cpu = 0; #endif #ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW local_irq_enable(); @@ -938,23 +931,15 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) #endif /* __ARCH_WANT_UNLOCKED_CTXSW */ /* - * Check whether the task is waking, we use this to synchronize ->cpus_allowed - * against ttwu(). - */ -static inline int task_is_waking(struct task_struct *p) -{ - return unlikely(p->state == TASK_WAKING); -} - -/* - * __task_rq_lock - lock the runqueue a given task resides on. - * Must be called interrupts disabled. + * __task_rq_lock - lock the rq @p resides on. */ static inline struct rq *__task_rq_lock(struct task_struct *p) __acquires(rq->lock) { struct rq *rq; + lockdep_assert_held(&p->pi_lock); + for (;;) { rq = task_rq(p); raw_spin_lock(&rq->lock); @@ -965,22 +950,22 @@ static inline struct rq *__task_rq_lock(struct task_struct *p) } /* - * task_rq_lock - lock the runqueue a given task resides on and disable - * interrupts. Note the ordering: we can safely lookup the task_rq without - * explicitly disabling preemption. + * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. */ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) + __acquires(p->pi_lock) __acquires(rq->lock) { struct rq *rq; for (;;) { - local_irq_save(*flags); + raw_spin_lock_irqsave(&p->pi_lock, *flags); rq = task_rq(p); raw_spin_lock(&rq->lock); if (likely(rq == task_rq(p))) return rq; - raw_spin_unlock_irqrestore(&rq->lock, *flags); + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } } @@ -990,10 +975,13 @@ static void __task_rq_unlock(struct rq *rq) raw_spin_unlock(&rq->lock); } -static inline void task_rq_unlock(struct rq *rq, unsigned long *flags) +static inline void +task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags) __releases(rq->lock) + __releases(p->pi_lock) { - raw_spin_unlock_irqrestore(&rq->lock, *flags); + raw_spin_unlock(&rq->lock); + raw_spin_unlock_irqrestore(&p->pi_lock, *flags); } /* @@ -1222,11 +1210,17 @@ int get_nohz_timer_target(void) int i; struct sched_domain *sd; + rcu_read_lock(); for_each_domain(cpu, sd) { - for_each_cpu(i, sched_domain_span(sd)) - if (!idle_cpu(i)) - return i; + for_each_cpu(i, sched_domain_span(sd)) { + if (!idle_cpu(i)) { + cpu = i; + goto unlock; + } + } } +unlock: + rcu_read_unlock(); return cpu; } /* @@ -1336,15 +1330,15 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight, { u64 tmp; + tmp = (u64)delta_exec * weight; + if (!lw->inv_weight) { if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST)) lw->inv_weight = 1; else - lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2) - / (lw->weight+1); + lw->inv_weight = WMULT_CONST / lw->weight; } - tmp = (u64)delta_exec * weight; /* * Check whether we'd overflow the 64-bit multiplication: */ @@ -1369,6 +1363,12 @@ static inline void update_load_sub(struct load_weight *lw, unsigned long dec) lw->inv_weight = 0; } +static inline void update_load_set(struct load_weight *lw, unsigned long w) +{ + lw->weight = w; + lw->inv_weight = 0; +} + /* * To aid in avoiding the subversion of "niceness" due to uneven distribution * of tasks with abnormal "nice" values across CPUs the contribution that @@ -1557,101 +1557,6 @@ static unsigned long cpu_avg_load_per_task(int cpu) #ifdef CONFIG_FAIR_GROUP_SCHED -static __read_mostly unsigned long __percpu *update_shares_data; - -static void __set_se_shares(struct sched_entity *se, unsigned long shares); - -/* - * Calculate and set the cpu's group shares. - */ -static void update_group_shares_cpu(struct task_group *tg, int cpu, - unsigned long sd_shares, - unsigned long sd_rq_weight, - unsigned long *usd_rq_weight) -{ - unsigned long shares, rq_weight; - int boost = 0; - - rq_weight = usd_rq_weight[cpu]; - if (!rq_weight) { - boost = 1; - rq_weight = NICE_0_LOAD; - } - - /* - * \Sum_j shares_j * rq_weight_i - * shares_i = ----------------------------- - * \Sum_j rq_weight_j - */ - shares = (sd_shares * rq_weight) / sd_rq_weight; - shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES); - - if (abs(shares - tg->se[cpu]->load.weight) > - sysctl_sched_shares_thresh) { - struct rq *rq = cpu_rq(cpu); - unsigned long flags; - - raw_spin_lock_irqsave(&rq->lock, flags); - tg->cfs_rq[cpu]->rq_weight = boost ? 0 : rq_weight; - tg->cfs_rq[cpu]->shares = boost ? 0 : shares; - __set_se_shares(tg->se[cpu], shares); - raw_spin_unlock_irqrestore(&rq->lock, flags); - } -} - -/* - * Re-compute the task group their per cpu shares over the given domain. - * This needs to be done in a bottom-up fashion because the rq weight of a - * parent group depends on the shares of its child groups. - */ -static int tg_shares_up(struct task_group *tg, void *data) -{ - unsigned long weight, rq_weight = 0, sum_weight = 0, shares = 0; - unsigned long *usd_rq_weight; - struct sched_domain *sd = data; - unsigned long flags; - int i; - - if (!tg->se[0]) - return 0; - - local_irq_save(flags); - usd_rq_weight = per_cpu_ptr(update_shares_data, smp_processor_id()); - - for_each_cpu(i, sched_domain_span(sd)) { - weight = tg->cfs_rq[i]->load.weight; - usd_rq_weight[i] = weight; - - rq_weight += weight; - /* - * If there are currently no tasks on the cpu pretend there - * is one of average load so that when a new task gets to - * run here it will not get delayed by group starvation. - */ - if (!weight) - weight = NICE_0_LOAD; - - sum_weight += weight; - shares += tg->cfs_rq[i]->shares; - } - - if (!rq_weight) - rq_weight = sum_weight; - - if ((!shares && rq_weight) || shares > tg->shares) - shares = tg->shares; - - if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE)) - shares = tg->shares; - - for_each_cpu(i, sched_domain_span(sd)) - update_group_shares_cpu(tg, i, shares, rq_weight, usd_rq_weight); - - local_irq_restore(flags); - - return 0; -} - /* * Compute the cpu's hierarchical load factor for each task group. * This needs to be done in a top-down fashion because the load of a child @@ -1666,7 +1571,7 @@ static int tg_load_down(struct task_group *tg, void *data) load = cpu_rq(cpu)->load.weight; } else { load = tg->parent->cfs_rq[cpu]->h_load; - load *= tg->cfs_rq[cpu]->shares; + load *= tg->se[cpu]->load.weight; load /= tg->parent->cfs_rq[cpu]->load.weight + 1; } @@ -1675,34 +1580,11 @@ static int tg_load_down(struct task_group *tg, void *data) return 0; } -static void update_shares(struct sched_domain *sd) -{ - s64 elapsed; - u64 now; - - if (root_task_group_empty()) - return; - - now = local_clock(); - elapsed = now - sd->last_update; - - if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) { - sd->last_update = now; - walk_tg_tree(tg_nop, tg_shares_up, sd); - } -} - static void update_h_load(long cpu) { walk_tg_tree(tg_load_down, tg_nop, (void *)cpu); } -#else - -static inline void update_shares(struct sched_domain *sd) -{ -} - #endif #ifdef CONFIG_PREEMPT @@ -1822,15 +1704,39 @@ static void double_rq_unlock(struct rq *rq1, struct rq *rq2) __release(rq2->lock); } -#endif +#else /* CONFIG_SMP */ -#ifdef CONFIG_FAIR_GROUP_SCHED -static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares) +/* + * double_rq_lock - safely lock two runqueues + * + * Note this does not disable interrupts like task_rq_lock, + * you need to do so manually before calling. + */ +static void double_rq_lock(struct rq *rq1, struct rq *rq2) + __acquires(rq1->lock) + __acquires(rq2->lock) { -#ifdef CONFIG_SMP - cfs_rq->shares = shares; -#endif + BUG_ON(!irqs_disabled()); + BUG_ON(rq1 != rq2); + raw_spin_lock(&rq1->lock); + __acquire(rq2->lock); /* Fake it out ;) */ } + +/* + * double_rq_unlock - safely unlock two runqueues + * + * Note this does not restore interrupts like task_rq_unlock, + * you need to do so manually after calling. + */ +static void double_rq_unlock(struct rq *rq1, struct rq *rq2) + __releases(rq1->lock) + __releases(rq2->lock) +{ + BUG_ON(rq1 != rq2); + raw_spin_unlock(&rq1->lock); + __release(rq2->lock); +} + #endif static void calc_load_account_idle(struct rq *this_rq); @@ -1890,7 +1796,6 @@ static void enqueue_task(struct rq *rq, struct task_struct *p, int flags) update_rq_clock(rq); sched_info_queued(p); p->sched_class->enqueue_task(rq, p, flags); - p->se.on_rq = 1; } static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) @@ -1898,7 +1803,6 @@ static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) update_rq_clock(rq); sched_info_dequeued(p); p->sched_class->dequeue_task(rq, p, flags); - p->se.on_rq = 0; } /* @@ -1934,10 +1838,9 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int flags) * They are read and saved off onto struct rq in update_rq_clock(). * This may result in other CPU reading this CPU's irq time and can * race with irq/account_system_vtime on this CPU. We would either get old - * or new value (or semi updated value on 32 bit) with a side effect of - * accounting a slice of irq time to wrong task when irq is in progress - * while we read rq->clock. That is a worthy compromise in place of having - * locks on each irq in account_system_time. + * or new value with a side effect of accounting a slice of irq time to wrong + * task when irq is in progress while we read rq->clock. That is a worthy + * compromise in place of having locks on each irq in account_system_time. */ static DEFINE_PER_CPU(u64, cpu_hardirq_time); static DEFINE_PER_CPU(u64, cpu_softirq_time); @@ -1955,19 +1858,58 @@ void disable_sched_clock_irqtime(void) sched_clock_irqtime = 0; } -static u64 irq_time_cpu(int cpu) +#ifndef CONFIG_64BIT +static DEFINE_PER_CPU(seqcount_t, irq_time_seq); + +static inline void irq_time_write_begin(void) { - if (!sched_clock_irqtime) - return 0; + __this_cpu_inc(irq_time_seq.sequence); + smp_wmb(); +} + +static inline void irq_time_write_end(void) +{ + smp_wmb(); + __this_cpu_inc(irq_time_seq.sequence); +} + +static inline u64 irq_time_read(int cpu) +{ + u64 irq_time; + unsigned seq; + + do { + seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu)); + irq_time = per_cpu(cpu_softirq_time, cpu) + + per_cpu(cpu_hardirq_time, cpu); + } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq)); + return irq_time; +} +#else /* CONFIG_64BIT */ +static inline void irq_time_write_begin(void) +{ +} + +static inline void irq_time_write_end(void) +{ +} + +static inline u64 irq_time_read(int cpu) +{ return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); } +#endif /* CONFIG_64BIT */ +/* + * Called before incrementing preempt_count on {soft,}irq_enter + * and before decrementing preempt_count on {soft,}irq_exit. + */ void account_system_vtime(struct task_struct *curr) { unsigned long flags; + s64 delta; int cpu; - u64 now, delta; if (!sched_clock_irqtime) return; @@ -1975,9 +1917,10 @@ void account_system_vtime(struct task_struct *curr) local_irq_save(flags); cpu = smp_processor_id(); - now = sched_clock_cpu(cpu); - delta = now - per_cpu(irq_start_time, cpu); - per_cpu(irq_start_time, cpu) = now; + delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time); + __this_cpu_add(irq_start_time, delta); + + irq_time_write_begin(); /* * We do not account for softirq time from ksoftirqd here. * We want to continue accounting softirq time to ksoftirqd thread @@ -1985,37 +1928,92 @@ void account_system_vtime(struct task_struct *curr) * that do not consume any time, but still wants to run. */ if (hardirq_count()) - per_cpu(cpu_hardirq_time, cpu) += delta; - else if (in_serving_softirq() && !(curr->flags & PF_KSOFTIRQD)) - per_cpu(cpu_softirq_time, cpu) += delta; + __this_cpu_add(cpu_hardirq_time, delta); + else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) + __this_cpu_add(cpu_softirq_time, delta); + irq_time_write_end(); local_irq_restore(flags); } EXPORT_SYMBOL_GPL(account_system_vtime); -static void sched_irq_time_avg_update(struct rq *rq, u64 curr_irq_time) +static void update_rq_clock_task(struct rq *rq, s64 delta) { - if (sched_clock_irqtime && sched_feat(NONIRQ_POWER)) { - u64 delta_irq = curr_irq_time - rq->prev_irq_time; - rq->prev_irq_time = curr_irq_time; - sched_rt_avg_update(rq, delta_irq); - } + s64 irq_delta; + + irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; + + /* + * Since irq_time is only updated on {soft,}irq_exit, we might run into + * this case when a previous update_rq_clock() happened inside a + * {soft,}irq region. + * + * When this happens, we stop ->clock_task and only update the + * prev_irq_time stamp to account for the part that fit, so that a next + * update will consume the rest. This ensures ->clock_task is + * monotonic. + * + * It does however cause some slight miss-attribution of {soft,}irq + * time, a more accurate solution would be to update the irq_time using + * the current rq->clock timestamp, except that would require using + * atomic ops. + */ + if (irq_delta > delta) + irq_delta = delta; + + rq->prev_irq_time += irq_delta; + delta -= irq_delta; + rq->clock_task += delta; + + if (irq_delta && sched_feat(NONIRQ_POWER)) + sched_rt_avg_update(rq, irq_delta); } -#else +static int irqtime_account_hi_update(void) +{ + struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + unsigned long flags; + u64 latest_ns; + int ret = 0; + + local_irq_save(flags); + latest_ns = this_cpu_read(cpu_hardirq_time); + if (cputime64_gt(nsecs_to_cputime64(latest_ns), cpustat->irq)) + ret = 1; + local_irq_restore(flags); + return ret; +} -static u64 irq_time_cpu(int cpu) +static int irqtime_account_si_update(void) { - return 0; + struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + unsigned long flags; + u64 latest_ns; + int ret = 0; + + local_irq_save(flags); + latest_ns = this_cpu_read(cpu_softirq_time); + if (cputime64_gt(nsecs_to_cputime64(latest_ns), cpustat->softirq)) + ret = 1; + local_irq_restore(flags); + return ret; } -static void sched_irq_time_avg_update(struct rq *rq, u64 curr_irq_time) { } +#else /* CONFIG_IRQ_TIME_ACCOUNTING */ -#endif +#define sched_clock_irqtime (0) + +static void update_rq_clock_task(struct rq *rq, s64 delta) +{ + rq->clock_task += delta; +} + +#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ #include "sched_idletask.c" #include "sched_fair.c" #include "sched_rt.c" +#include "sched_autogroup.c" #include "sched_stoptask.c" #ifdef CONFIG_SCHED_DEBUG # include "sched_debug.c" @@ -2108,14 +2106,39 @@ inline int task_curr(const struct task_struct *p) static inline void check_class_changed(struct rq *rq, struct task_struct *p, const struct sched_class *prev_class, - int oldprio, int running) + int oldprio) { if (prev_class != p->sched_class) { if (prev_class->switched_from) - prev_class->switched_from(rq, p, running); - p->sched_class->switched_to(rq, p, running); - } else - p->sched_class->prio_changed(rq, p, oldprio, running); + prev_class->switched_from(rq, p); + p->sched_class->switched_to(rq, p); + } else if (oldprio != p->prio) + p->sched_class->prio_changed(rq, p, oldprio); +} + +static void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) +{ + const struct sched_class *class; + + if (p->sched_class == rq->curr->sched_class) { + rq->curr->sched_class->check_preempt_curr(rq, p, flags); + } else { + for_each_class(class) { + if (class == rq->curr->sched_class) + break; + if (class == p->sched_class) { + resched_task(rq->curr); + break; + } + } + } + + /* + * A queue event has occurred, and we're going to schedule. In + * this case, we can save a useless back to back clock update. + */ + if (rq->curr->on_rq && test_tsk_need_resched(rq->curr)) + rq->skip_clock_update = 1; } #ifdef CONFIG_SMP @@ -2160,6 +2183,11 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) */ WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING && !(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE)); + +#ifdef CONFIG_LOCKDEP + WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || + lockdep_is_held(&task_rq(p)->lock))); +#endif #endif trace_sched_migrate_task(p, new_cpu); @@ -2180,21 +2208,6 @@ struct migration_arg { static int migration_cpu_stop(void *data); /* - * The task's runqueue lock must be held. - * Returns true if you have to wait for migration thread. - */ -static bool migrate_task(struct task_struct *p, int dest_cpu) -{ - struct rq *rq = task_rq(p); - - /* - * If the task is not on a runqueue (and not running), then - * the next wake-up will properly place the task. - */ - return p->se.on_rq || task_running(rq, p); -} - -/* * wait_task_inactive - wait for a thread to unschedule. * * If @match_state is nonzero, it's the @p->state value just checked and @@ -2251,11 +2264,11 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) rq = task_rq_lock(p, &flags); trace_sched_wait_task(p); running = task_running(rq, p); - on_rq = p->se.on_rq; + on_rq = p->on_rq; ncsw = 0; if (!match_state || p->state == match_state) ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); /* * If it changed from the expected state, bail out now. @@ -2284,7 +2297,10 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) * yield - it could be a while. */ if (unlikely(on_rq)) { - schedule_timeout_uninterruptible(1); + ktime_t to = ktime_set(0, NSEC_PER_SEC/HZ); + + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_hrtimeout(&to, HRTIMER_MODE_REL); continue; } @@ -2306,7 +2322,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state) * Cause a process which is running on another CPU to enter * kernel-mode, without any delay. (to get signals handled.) * - * NOTE: this function doesnt have to take the runqueue lock, + * NOTE: this function doesn't have to take the runqueue lock, * because all it wants to ensure is that the remote task enters * the kernel. If the IPI races and the task has been migrated * to another CPU then no harm is done and the purpose has been @@ -2325,30 +2341,9 @@ void kick_process(struct task_struct *p) EXPORT_SYMBOL_GPL(kick_process); #endif /* CONFIG_SMP */ -/** - * task_oncpu_function_call - call a function on the cpu on which a task runs - * @p: the task to evaluate - * @func: the function to be called - * @info: the function call argument - * - * Calls the function @func when the task is currently running. This might - * be on the current CPU, which just calls the function directly - */ -void task_oncpu_function_call(struct task_struct *p, - void (*func) (void *info), void *info) -{ - int cpu; - - preempt_disable(); - cpu = task_cpu(p); - if (task_curr(p)) - smp_call_function_single(cpu, func, info, 1); - preempt_enable(); -} - #ifdef CONFIG_SMP /* - * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held. + * ->cpus_allowed is protected by both rq->lock and p->pi_lock */ static int select_fallback_rq(int cpu, struct task_struct *p) { @@ -2366,30 +2361,27 @@ static int select_fallback_rq(int cpu, struct task_struct *p) return dest_cpu; /* No more Mr. Nice Guy. */ - if (unlikely(dest_cpu >= nr_cpu_ids)) { - dest_cpu = cpuset_cpus_allowed_fallback(p); - /* - * Don't tell them about moving exiting tasks or - * kernel threads (both mm NULL), since they never - * leave kernel. - */ - if (p->mm && printk_ratelimit()) { - printk(KERN_INFO "process %d (%s) no " - "longer affine to cpu%d\n", - task_pid_nr(p), p->comm, cpu); - } + dest_cpu = cpuset_cpus_allowed_fallback(p); + /* + * Don't tell them about moving exiting tasks or + * kernel threads (both mm NULL), since they never + * leave kernel. + */ + if (p->mm && printk_ratelimit()) { + printk(KERN_INFO "process %d (%s) no longer affine to cpu%d\n", + task_pid_nr(p), p->comm, cpu); } return dest_cpu; } /* - * The caller (fork, wakeup) owns TASK_WAKING, ->cpus_allowed is stable. + * The caller (fork, wakeup) owns p->pi_lock, ->cpus_allowed is stable. */ static inline -int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_flags) +int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags) { - int cpu = p->sched_class->select_task_rq(rq, p, sd_flags, wake_flags); + int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags); /* * In order not to call set_task_cpu() on a blocking task we need @@ -2415,27 +2407,62 @@ static void update_avg(u64 *avg, u64 sample) } #endif -static inline void ttwu_activate(struct task_struct *p, struct rq *rq, - bool is_sync, bool is_migrate, bool is_local, - unsigned long en_flags) +static void +ttwu_stat(struct task_struct *p, int cpu, int wake_flags) { +#ifdef CONFIG_SCHEDSTATS + struct rq *rq = this_rq(); + +#ifdef CONFIG_SMP + int this_cpu = smp_processor_id(); + + if (cpu == this_cpu) { + schedstat_inc(rq, ttwu_local); + schedstat_inc(p, se.statistics.nr_wakeups_local); + } else { + struct sched_domain *sd; + + schedstat_inc(p, se.statistics.nr_wakeups_remote); + rcu_read_lock(); + for_each_domain(this_cpu, sd) { + if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { + schedstat_inc(sd, ttwu_wake_remote); + break; + } + } + rcu_read_unlock(); + } +#endif /* CONFIG_SMP */ + + schedstat_inc(rq, ttwu_count); schedstat_inc(p, se.statistics.nr_wakeups); - if (is_sync) + + if (wake_flags & WF_SYNC) schedstat_inc(p, se.statistics.nr_wakeups_sync); - if (is_migrate) + + if (cpu != task_cpu(p)) schedstat_inc(p, se.statistics.nr_wakeups_migrate); - if (is_local) - schedstat_inc(p, se.statistics.nr_wakeups_local); - else - schedstat_inc(p, se.statistics.nr_wakeups_remote); +#endif /* CONFIG_SCHEDSTATS */ +} + +static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags) +{ activate_task(rq, p, en_flags); + p->on_rq = 1; + + /* if a worker is waking up, notify workqueue */ + if (p->flags & PF_WQ_WORKER) + wq_worker_waking_up(p, cpu_of(rq)); } -static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, - int wake_flags, bool success) +/* + * Mark the task runnable and perform wakeup-preemption. + */ +static void +ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) { - trace_sched_wakeup(p, success); + trace_sched_wakeup(p, true); check_preempt_curr(rq, p, wake_flags); p->state = TASK_RUNNING; @@ -2454,9 +2481,99 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, rq->idle_stamp = 0; } #endif - /* if a worker is waking up, notify workqueue */ - if ((p->flags & PF_WQ_WORKER) && success) - wq_worker_waking_up(p, cpu_of(rq)); +} + +static void +ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) +{ +#ifdef CONFIG_SMP + if (p->sched_contributes_to_load) + rq->nr_uninterruptible--; +#endif + + ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING); + ttwu_do_wakeup(rq, p, wake_flags); +} + +/* + * Called in case the task @p isn't fully descheduled from its runqueue, + * in this case we must do a remote wakeup. Its a 'light' wakeup though, + * since all we need to do is flip p->state to TASK_RUNNING, since + * the task is still ->on_rq. + */ +static int ttwu_remote(struct task_struct *p, int wake_flags) +{ + struct rq *rq; + int ret = 0; + + rq = __task_rq_lock(p); + if (p->on_rq) { + ttwu_do_wakeup(rq, p, wake_flags); + ret = 1; + } + __task_rq_unlock(rq); + + return ret; +} + +#ifdef CONFIG_SMP +static void sched_ttwu_pending(void) +{ + struct rq *rq = this_rq(); + struct task_struct *list = xchg(&rq->wake_list, NULL); + + if (!list) + return; + + raw_spin_lock(&rq->lock); + + while (list) { + struct task_struct *p = list; + list = list->wake_entry; + ttwu_do_activate(rq, p, 0); + } + + raw_spin_unlock(&rq->lock); +} + +void scheduler_ipi(void) +{ + sched_ttwu_pending(); +} + +static void ttwu_queue_remote(struct task_struct *p, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + struct task_struct *next = rq->wake_list; + + for (;;) { + struct task_struct *old = next; + + p->wake_entry = next; + next = cmpxchg(&rq->wake_list, old, p); + if (next == old) + break; + } + + if (!next) + smp_send_reschedule(cpu); +} +#endif + +static void ttwu_queue(struct task_struct *p, int cpu) +{ + struct rq *rq = cpu_rq(cpu); + +#if defined(CONFIG_SMP) && defined(CONFIG_SCHED_TTWU_QUEUE) + if (sched_feat(TTWU_QUEUE) && cpu != smp_processor_id()) { + ttwu_queue_remote(p, cpu); + return; + } +#endif + + raw_spin_lock(&rq->lock); + ttwu_do_activate(rq, p, 0); + raw_spin_unlock(&rq->lock); } /** @@ -2474,92 +2591,64 @@ static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, * Returns %true if @p was woken up, %false if it was already running * or @state didn't match @p's state. */ -static int try_to_wake_up(struct task_struct *p, unsigned int state, - int wake_flags) +static int +try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) { - int cpu, orig_cpu, this_cpu, success = 0; unsigned long flags; - unsigned long en_flags = ENQUEUE_WAKEUP; - struct rq *rq; - - this_cpu = get_cpu(); + int cpu, success = 0; smp_wmb(); - rq = task_rq_lock(p, &flags); + raw_spin_lock_irqsave(&p->pi_lock, flags); if (!(p->state & state)) goto out; - if (p->se.on_rq) - goto out_running; - + success = 1; /* we're going to change ->state */ cpu = task_cpu(p); - orig_cpu = cpu; -#ifdef CONFIG_SMP - if (unlikely(task_running(rq, p))) - goto out_activate; + if (p->on_rq && ttwu_remote(p, wake_flags)) + goto stat; +#ifdef CONFIG_SMP /* - * In order to handle concurrent wakeups and release the rq->lock - * we put the task in TASK_WAKING state. - * - * First fix up the nr_uninterruptible count: + * If the owning (remote) cpu is still in the middle of schedule() with + * this task as prev, wait until its done referencing the task. */ - if (task_contributes_to_load(p)) { - if (likely(cpu_online(orig_cpu))) - rq->nr_uninterruptible--; - else - this_rq()->nr_uninterruptible--; - } - p->state = TASK_WAKING; - - if (p->sched_class->task_waking) { - p->sched_class->task_waking(rq, p); - en_flags |= ENQUEUE_WAKING; + while (p->on_cpu) { +#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW + /* + * If called from interrupt context we could have landed in the + * middle of schedule(), in this case we should take care not + * to spin on ->on_cpu if p is current, since that would + * deadlock. + */ + if (p == current) { + ttwu_queue(p, cpu); + goto stat; + } +#endif + cpu_relax(); } - - cpu = select_task_rq(rq, p, SD_BALANCE_WAKE, wake_flags); - if (cpu != orig_cpu) - set_task_cpu(p, cpu); - __task_rq_unlock(rq); - - rq = cpu_rq(cpu); - raw_spin_lock(&rq->lock); - /* - * We migrated the task without holding either rq->lock, however - * since the task is not on the task list itself, nobody else - * will try and migrate the task, hence the rq should match the - * cpu we just moved it to. + * Pairs with the smp_wmb() in finish_lock_switch(). */ - WARN_ON(task_cpu(p) != cpu); - WARN_ON(p->state != TASK_WAKING); + smp_rmb(); -#ifdef CONFIG_SCHEDSTATS - schedstat_inc(rq, ttwu_count); - if (cpu == this_cpu) - schedstat_inc(rq, ttwu_local); - else { - struct sched_domain *sd; - for_each_domain(this_cpu, sd) { - if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { - schedstat_inc(sd, ttwu_wake_remote); - break; - } - } - } -#endif /* CONFIG_SCHEDSTATS */ + p->sched_contributes_to_load = !!task_contributes_to_load(p); + p->state = TASK_WAKING; -out_activate: + if (p->sched_class->task_waking) + p->sched_class->task_waking(p); + + cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags); + if (task_cpu(p) != cpu) + set_task_cpu(p, cpu); #endif /* CONFIG_SMP */ - ttwu_activate(p, rq, wake_flags & WF_SYNC, orig_cpu != cpu, - cpu == this_cpu, en_flags); - success = 1; -out_running: - ttwu_post_activation(p, rq, wake_flags, success); + + ttwu_queue(p, cpu); +stat: + ttwu_stat(p, cpu, wake_flags); out: - task_rq_unlock(rq, &flags); - put_cpu(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); return success; } @@ -2568,31 +2657,34 @@ out: * try_to_wake_up_local - try to wake up a local task with rq lock held * @p: the thread to be awakened * - * Put @p on the run-queue if it's not alredy there. The caller must + * Put @p on the run-queue if it's not already there. The caller must * ensure that this_rq() is locked, @p is bound to this_rq() and not - * the current task. this_rq() stays locked over invocation. + * the current task. */ static void try_to_wake_up_local(struct task_struct *p) { struct rq *rq = task_rq(p); - bool success = false; BUG_ON(rq != this_rq()); BUG_ON(p == current); lockdep_assert_held(&rq->lock); + if (!raw_spin_trylock(&p->pi_lock)) { + raw_spin_unlock(&rq->lock); + raw_spin_lock(&p->pi_lock); + raw_spin_lock(&rq->lock); + } + if (!(p->state & TASK_NORMAL)) - return; + goto out; - if (!p->se.on_rq) { - if (likely(!task_running(rq, p))) { - schedstat_inc(rq, ttwu_count); - schedstat_inc(rq, ttwu_local); - } - ttwu_activate(p, rq, false, false, true, ENQUEUE_WAKEUP); - success = true; - } - ttwu_post_activation(p, rq, 0, success); + if (!p->on_rq) + ttwu_activate(rq, p, ENQUEUE_WAKEUP); + + ttwu_do_wakeup(rq, p, 0); + ttwu_stat(p, smp_processor_id(), 0); +out: + raw_spin_unlock(&p->pi_lock); } /** @@ -2625,18 +2717,21 @@ int wake_up_state(struct task_struct *p, unsigned int state) */ static void __sched_fork(struct task_struct *p) { + p->on_rq = 0; + + p->se.on_rq = 0; p->se.exec_start = 0; p->se.sum_exec_runtime = 0; p->se.prev_sum_exec_runtime = 0; p->se.nr_migrations = 0; + p->se.vruntime = 0; + INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_SCHEDSTATS memset(&p->se.statistics, 0, sizeof(p->se.statistics)); #endif INIT_LIST_HEAD(&p->rt.run_list); - p->se.on_rq = 0; - INIT_LIST_HEAD(&p->se.group_node); #ifdef CONFIG_PREEMPT_NOTIFIERS INIT_HLIST_HEAD(&p->preempt_notifiers); @@ -2646,8 +2741,9 @@ static void __sched_fork(struct task_struct *p) /* * fork()/clone()-time setup: */ -void sched_fork(struct task_struct *p, int clone_flags) +void sched_fork(struct task_struct *p) { + unsigned long flags; int cpu = get_cpu(); __sched_fork(p); @@ -2698,22 +2794,24 @@ void sched_fork(struct task_struct *p, int clone_flags) * * Silence PROVE_RCU. */ - rcu_read_lock(); + raw_spin_lock_irqsave(&p->pi_lock, flags); set_task_cpu(p, cpu); - rcu_read_unlock(); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) if (likely(sched_info_on())) memset(&p->sched_info, 0, sizeof(p->sched_info)); #endif -#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) - p->oncpu = 0; +#if defined(CONFIG_SMP) + p->on_cpu = 0; #endif #ifdef CONFIG_PREEMPT /* Want to start with kernel preemption disabled. */ task_thread_info(p)->preempt_count = 1; #endif +#ifdef CONFIG_SMP plist_node_init(&p->pushable_tasks, MAX_PRIO); +#endif put_cpu(); } @@ -2725,41 +2823,31 @@ void sched_fork(struct task_struct *p, int clone_flags) * that must be done for every newly created context, then puts the task * on the runqueue and wakes it. */ -void wake_up_new_task(struct task_struct *p, unsigned long clone_flags) +void wake_up_new_task(struct task_struct *p) { unsigned long flags; struct rq *rq; - int cpu __maybe_unused = get_cpu(); + raw_spin_lock_irqsave(&p->pi_lock, flags); #ifdef CONFIG_SMP - rq = task_rq_lock(p, &flags); - p->state = TASK_WAKING; - /* * Fork balancing, do it here and not earlier because: * - cpus_allowed can change in the fork path * - any previously selected cpu might disappear through hotplug - * - * We set TASK_WAKING so that select_task_rq() can drop rq->lock - * without people poking at ->cpus_allowed. */ - cpu = select_task_rq(rq, p, SD_BALANCE_FORK, 0); - set_task_cpu(p, cpu); - - p->state = TASK_RUNNING; - task_rq_unlock(rq, &flags); + set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0)); #endif - rq = task_rq_lock(p, &flags); + rq = __task_rq_lock(p); activate_task(rq, p, 0); - trace_sched_wakeup_new(p, 1); + p->on_rq = 1; + trace_sched_wakeup_new(p, true); check_preempt_curr(rq, p, WF_FORK); #ifdef CONFIG_SMP if (p->sched_class->task_woken) p->sched_class->task_woken(rq, p); #endif - task_rq_unlock(rq, &flags); - put_cpu(); + task_rq_unlock(rq, p, &flags); } #ifdef CONFIG_PREEMPT_NOTIFIERS @@ -2837,9 +2925,12 @@ static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { + sched_info_switch(prev, next); + perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); prepare_lock_switch(rq, next); prepare_arch_switch(next); + trace_sched_switch(prev, next); } /** @@ -2972,7 +3063,7 @@ context_switch(struct rq *rq, struct task_struct *prev, struct mm_struct *mm, *oldmm; prepare_task_switch(rq, prev, next); - trace_sched_switch(prev, next); + mm = next->mm; oldmm = prev->active_mm; /* @@ -3104,6 +3195,15 @@ static long calc_load_fold_active(struct rq *this_rq) return delta; } +static unsigned long +calc_load(unsigned long load, unsigned long exp, unsigned long active) +{ + load *= exp; + load += active * (FIXED_1 - exp); + load += 1UL << (FSHIFT - 1); + return load >> FSHIFT; +} + #ifdef CONFIG_NO_HZ /* * For NO_HZ we delay the active fold to the next LOAD_FREQ update. @@ -3133,6 +3233,128 @@ static long calc_load_fold_idle(void) return delta; } + +/** + * fixed_power_int - compute: x^n, in O(log n) time + * + * @x: base of the power + * @frac_bits: fractional bits of @x + * @n: power to raise @x to. + * + * By exploiting the relation between the definition of the natural power + * function: x^n := x*x*...*x (x multiplied by itself for n times), and + * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i, + * (where: n_i \elem {0, 1}, the binary vector representing n), + * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is + * of course trivially computable in O(log_2 n), the length of our binary + * vector. + */ +static unsigned long +fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n) +{ + unsigned long result = 1UL << frac_bits; + + if (n) for (;;) { + if (n & 1) { + result *= x; + result += 1UL << (frac_bits - 1); + result >>= frac_bits; + } + n >>= 1; + if (!n) + break; + x *= x; + x += 1UL << (frac_bits - 1); + x >>= frac_bits; + } + + return result; +} + +/* + * a1 = a0 * e + a * (1 - e) + * + * a2 = a1 * e + a * (1 - e) + * = (a0 * e + a * (1 - e)) * e + a * (1 - e) + * = a0 * e^2 + a * (1 - e) * (1 + e) + * + * a3 = a2 * e + a * (1 - e) + * = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e) + * = a0 * e^3 + a * (1 - e) * (1 + e + e^2) + * + * ... + * + * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1] + * = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e) + * = a0 * e^n + a * (1 - e^n) + * + * [1] application of the geometric series: + * + * n 1 - x^(n+1) + * S_n := \Sum x^i = ------------- + * i=0 1 - x + */ +static unsigned long +calc_load_n(unsigned long load, unsigned long exp, + unsigned long active, unsigned int n) +{ + + return calc_load(load, fixed_power_int(exp, FSHIFT, n), active); +} + +/* + * NO_HZ can leave us missing all per-cpu ticks calling + * calc_load_account_active(), but since an idle CPU folds its delta into + * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold + * in the pending idle delta if our idle period crossed a load cycle boundary. + * + * Once we've updated the global active value, we need to apply the exponential + * weights adjusted to the number of cycles missed. + */ +static void calc_global_nohz(unsigned long ticks) +{ + long delta, active, n; + + if (time_before(jiffies, calc_load_update)) + return; + + /* + * If we crossed a calc_load_update boundary, make sure to fold + * any pending idle changes, the respective CPUs might have + * missed the tick driven calc_load_account_active() update + * due to NO_HZ. + */ + delta = calc_load_fold_idle(); + if (delta) + atomic_long_add(delta, &calc_load_tasks); + + /* + * If we were idle for multiple load cycles, apply them. + */ + if (ticks >= LOAD_FREQ) { + n = ticks / LOAD_FREQ; + + active = atomic_long_read(&calc_load_tasks); + active = active > 0 ? active * FIXED_1 : 0; + + avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n); + avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n); + avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n); + + calc_load_update += n * LOAD_FREQ; + } + + /* + * Its possible the remainder of the above division also crosses + * a LOAD_FREQ period, the regular check in calc_global_load() + * which comes after this will take care of that. + * + * Consider us being 11 ticks before a cycle completion, and us + * sleeping for 4*LOAD_FREQ + 22 ticks, then the above code will + * age us 4 cycles, and the test in calc_global_load() will + * pick up the final one. + */ +} #else static void calc_load_account_idle(struct rq *this_rq) { @@ -3142,6 +3364,10 @@ static inline long calc_load_fold_idle(void) { return 0; } + +static void calc_global_nohz(unsigned long ticks) +{ +} #endif /** @@ -3159,24 +3385,17 @@ void get_avenrun(unsigned long *loads, unsigned long offset, int shift) loads[2] = (avenrun[2] + offset) << shift; } -static unsigned long -calc_load(unsigned long load, unsigned long exp, unsigned long active) -{ - load *= exp; - load += active * (FIXED_1 - exp); - return load >> FSHIFT; -} - /* * calc_load - update the avenrun load estimates 10 ticks after the * CPUs have updated calc_load_tasks. */ -void calc_global_load(void) +void calc_global_load(unsigned long ticks) { - unsigned long upd = calc_load_update + 10; long active; - if (time_before(jiffies, upd)) + calc_global_nohz(ticks); + + if (time_before(jiffies, calc_load_update + 10)) return; active = atomic_long_read(&calc_load_tasks); @@ -3337,27 +3556,22 @@ void sched_exec(void) { struct task_struct *p = current; unsigned long flags; - struct rq *rq; int dest_cpu; - rq = task_rq_lock(p, &flags); - dest_cpu = p->sched_class->select_task_rq(rq, p, SD_BALANCE_EXEC, 0); + raw_spin_lock_irqsave(&p->pi_lock, flags); + dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0); if (dest_cpu == smp_processor_id()) goto unlock; - /* - * select_task_rq() can race against ->cpus_allowed - */ - if (cpumask_test_cpu(dest_cpu, &p->cpus_allowed) && - likely(cpu_active(dest_cpu)) && migrate_task(p, dest_cpu)) { + if (likely(cpu_active(dest_cpu))) { struct migration_arg arg = { p, dest_cpu }; - task_rq_unlock(rq, &flags); - stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); + stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); return; } unlock: - task_rq_unlock(rq, &flags); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); } #endif @@ -3394,7 +3608,7 @@ unsigned long long task_delta_exec(struct task_struct *p) rq = task_rq_lock(p, &flags); ns = do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3412,7 +3626,7 @@ unsigned long long task_sched_runtime(struct task_struct *p) rq = task_rq_lock(p, &flags); ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3436,7 +3650,7 @@ unsigned long long thread_group_sched_runtime(struct task_struct *p) rq = task_rq_lock(p, &flags); thread_group_cputime(p, &totals); ns = totals.sum_exec_runtime + do_task_delta_exec(p, rq); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ns; } @@ -3501,6 +3715,32 @@ static void account_guest_time(struct task_struct *p, cputime_t cputime, } /* + * Account system cpu time to a process and desired cpustat field + * @p: the process that the cpu time gets accounted to + * @cputime: the cpu time spent in kernel space since the last update + * @cputime_scaled: cputime scaled by cpu frequency + * @target_cputime64: pointer to cpustat field that has to be updated + */ +static inline +void __account_system_time(struct task_struct *p, cputime_t cputime, + cputime_t cputime_scaled, cputime64_t *target_cputime64) +{ + cputime64_t tmp = cputime_to_cputime64(cputime); + + /* Add system time to process. */ + p->stime = cputime_add(p->stime, cputime); + p->stimescaled = cputime_add(p->stimescaled, cputime_scaled); + account_group_system_time(p, cputime); + + /* Add system time to cpustat. */ + *target_cputime64 = cputime64_add(*target_cputime64, tmp); + cpuacct_update_stats(p, CPUACCT_STAT_SYSTEM, cputime); + + /* Account for system time used */ + acct_update_integrals(p); +} + +/* * Account system cpu time to a process. * @p: the process that the cpu time gets accounted to * @hardirq_offset: the offset to subtract from hardirq_count() @@ -3511,36 +3751,26 @@ void account_system_time(struct task_struct *p, int hardirq_offset, cputime_t cputime, cputime_t cputime_scaled) { struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; - cputime64_t tmp; + cputime64_t *target_cputime64; if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) { account_guest_time(p, cputime, cputime_scaled); return; } - /* Add system time to process. */ - p->stime = cputime_add(p->stime, cputime); - p->stimescaled = cputime_add(p->stimescaled, cputime_scaled); - account_group_system_time(p, cputime); - - /* Add system time to cpustat. */ - tmp = cputime_to_cputime64(cputime); if (hardirq_count() - hardirq_offset) - cpustat->irq = cputime64_add(cpustat->irq, tmp); + target_cputime64 = &cpustat->irq; else if (in_serving_softirq()) - cpustat->softirq = cputime64_add(cpustat->softirq, tmp); + target_cputime64 = &cpustat->softirq; else - cpustat->system = cputime64_add(cpustat->system, tmp); - - cpuacct_update_stats(p, CPUACCT_STAT_SYSTEM, cputime); + target_cputime64 = &cpustat->system; - /* Account for system time used */ - acct_update_integrals(p); + __account_system_time(p, cputime, cputime_scaled, target_cputime64); } /* * Account for involuntary wait time. - * @steal: the cpu time spent in involuntary wait + * @cputime: the cpu time spent in involuntary wait */ void account_steal_time(cputime_t cputime) { @@ -3568,6 +3798,73 @@ void account_idle_time(cputime_t cputime) #ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifdef CONFIG_IRQ_TIME_ACCOUNTING +/* + * Account a tick to a process and cpustat + * @p: the process that the cpu time gets accounted to + * @user_tick: is the tick from userspace + * @rq: the pointer to rq + * + * Tick demultiplexing follows the order + * - pending hardirq update + * - pending softirq update + * - user_time + * - idle_time + * - system time + * - check for guest_time + * - else account as system_time + * + * Check for hardirq is done both for system and user time as there is + * no timer going off while we are on hardirq and hence we may never get an + * opportunity to update it solely in system time. + * p->stime and friends are only updated on system time and not on irq + * softirq as those do not count in task exec_runtime any more. + */ +static void irqtime_account_process_tick(struct task_struct *p, int user_tick, + struct rq *rq) +{ + cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); + cputime64_t tmp = cputime_to_cputime64(cputime_one_jiffy); + struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat; + + if (irqtime_account_hi_update()) { + cpustat->irq = cputime64_add(cpustat->irq, tmp); + } else if (irqtime_account_si_update()) { + cpustat->softirq = cputime64_add(cpustat->softirq, tmp); + } else if (this_cpu_ksoftirqd() == p) { + /* + * ksoftirqd time do not get accounted in cpu_softirq_time. + * So, we have to handle it separately here. + * Also, p->stime needs to be updated for ksoftirqd. + */ + __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, + &cpustat->softirq); + } else if (user_tick) { + account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); + } else if (p == rq->idle) { + account_idle_time(cputime_one_jiffy); + } else if (p->flags & PF_VCPU) { /* System time or guest time */ + account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled); + } else { + __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled, + &cpustat->system); + } +} + +static void irqtime_account_idle_ticks(int ticks) +{ + int i; + struct rq *rq = this_rq(); + + for (i = 0; i < ticks; i++) + irqtime_account_process_tick(current, 0, rq); +} +#else /* CONFIG_IRQ_TIME_ACCOUNTING */ +static void irqtime_account_idle_ticks(int ticks) {} +static void irqtime_account_process_tick(struct task_struct *p, int user_tick, + struct rq *rq) {} +#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ + /* * Account a single tick of cpu time. * @p: the process that the cpu time gets accounted to @@ -3578,6 +3875,11 @@ void account_process_tick(struct task_struct *p, int user_tick) cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); struct rq *rq = this_rq(); + if (sched_clock_irqtime) { + irqtime_account_process_tick(p, user_tick, rq); + return; + } + if (user_tick) account_user_time(p, cputime_one_jiffy, one_jiffy_scaled); else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET)) @@ -3603,6 +3905,12 @@ void account_steal_ticks(unsigned long ticks) */ void account_idle_ticks(unsigned long ticks) { + + if (sched_clock_irqtime) { + irqtime_account_idle_ticks(ticks); + return; + } + account_idle_time(jiffies_to_cputime(ticks)); } @@ -3696,9 +4004,6 @@ void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st) /* * This function gets called by the timer code, with HZ frequency. * We call it with interrupts disabled. - * - * It also gets called by the fork code, when changing the parent's - * timeslices. */ void scheduler_tick(void) { @@ -3818,19 +4123,12 @@ static inline void schedule_debug(struct task_struct *prev) profile_hit(SCHED_PROFILING, __builtin_return_address(0)); schedstat_inc(this_rq(), sched_count); -#ifdef CONFIG_SCHEDSTATS - if (unlikely(prev->lock_depth >= 0)) { - schedstat_inc(this_rq(), bkl_count); - schedstat_inc(prev, sched_info.bkl_count); - } -#endif } static void put_prev_task(struct rq *rq, struct task_struct *prev) { - if (prev->se.on_rq) + if (prev->on_rq || rq->skip_clock_update < 0) update_rq_clock(rq); - rq->skip_clock_update = 0; prev->sched_class->put_prev_task(rq, prev); } @@ -3879,27 +4177,25 @@ need_resched: rcu_note_context_switch(cpu); prev = rq->curr; - release_kernel_lock(prev); -need_resched_nonpreemptible: - schedule_debug(prev); if (sched_feat(HRTICK)) hrtick_clear(rq); raw_spin_lock_irq(&rq->lock); - clear_tsk_need_resched(prev); switch_count = &prev->nivcsw; if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; } else { + deactivate_task(rq, prev, DEQUEUE_SLEEP); + prev->on_rq = 0; + /* - * If a worker is going to sleep, notify and - * ask workqueue whether it wants to wake up a - * task to maintain concurrency. If so, wake - * up the task. + * If a worker went to sleep, notify and ask workqueue + * whether it wants to wake up a task to maintain + * concurrency. */ if (prev->flags & PF_WQ_WORKER) { struct task_struct *to_wakeup; @@ -3908,7 +4204,16 @@ need_resched_nonpreemptible: if (to_wakeup) try_to_wake_up_local(to_wakeup); } - deactivate_task(rq, prev, DEQUEUE_SLEEP); + + /* + * If we are going to sleep and we have plugged IO + * queued, make sure to submit it to avoid deadlocks. + */ + if (blk_needs_flush_plug(prev)) { + raw_spin_unlock(&rq->lock); + blk_schedule_flush_plug(prev); + raw_spin_lock(&rq->lock); + } } switch_count = &prev->nvcsw; } @@ -3920,11 +4225,10 @@ need_resched_nonpreemptible: put_prev_task(rq, prev); next = pick_next_task(rq); + clear_tsk_need_resched(prev); + rq->skip_clock_update = 0; if (likely(prev != next)) { - sched_info_switch(prev, next); - perf_event_task_sched_out(prev, next); - rq->nr_switches++; rq->curr = next; ++*switch_count; @@ -3943,9 +4247,6 @@ need_resched_nonpreemptible: post_schedule(rq); - if (unlikely(reacquire_kernel_lock(prev))) - goto need_resched_nonpreemptible; - preempt_enable_no_resched(); if (need_resched()) goto need_resched; @@ -3953,70 +4254,53 @@ need_resched_nonpreemptible: EXPORT_SYMBOL(schedule); #ifdef CONFIG_MUTEX_SPIN_ON_OWNER + +static inline bool owner_running(struct mutex *lock, struct task_struct *owner) +{ + bool ret = false; + + rcu_read_lock(); + if (lock->owner != owner) + goto fail; + + /* + * Ensure we emit the owner->on_cpu, dereference _after_ checking + * lock->owner still matches owner, if that fails, owner might + * point to free()d memory, if it still matches, the rcu_read_lock() + * ensures the memory stays valid. + */ + barrier(); + + ret = owner->on_cpu; +fail: + rcu_read_unlock(); + + return ret; +} + /* * Look out! "owner" is an entirely speculative pointer * access and not reliable. */ -int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner) +int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner) { - unsigned int cpu; - struct rq *rq; - if (!sched_feat(OWNER_SPIN)) return 0; -#ifdef CONFIG_DEBUG_PAGEALLOC - /* - * Need to access the cpu field knowing that - * DEBUG_PAGEALLOC could have unmapped it if - * the mutex owner just released it and exited. - */ - if (probe_kernel_address(&owner->cpu, cpu)) - return 0; -#else - cpu = owner->cpu; -#endif + while (owner_running(lock, owner)) { + if (need_resched()) + return 0; - /* - * Even if the access succeeded (likely case), - * the cpu field may no longer be valid. - */ - if (cpu >= nr_cpumask_bits) - return 0; + arch_mutex_cpu_relax(); + } /* - * We need to validate that we can do a - * get_cpu() and that we have the percpu area. + * If the owner changed to another task there is likely + * heavy contention, stop spinning. */ - if (!cpu_online(cpu)) + if (lock->owner) return 0; - rq = cpu_rq(cpu); - - for (;;) { - /* - * Owner changed, break to re-assess state. - */ - if (lock->owner != owner) { - /* - * If the lock has switched to a different owner, - * we likely have heavy contention. Return 0 to quit - * optimistic spinning and not contend further: - */ - if (lock->owner) - return 0; - break; - } - - /* - * Is that owner really running on that cpu? - */ - if (task_thread_info(rq->curr) != owner || need_resched()) - return 0; - - cpu_relax(); - } - return 1; } #endif @@ -4146,6 +4430,7 @@ void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key) { __wake_up_common(q, mode, 1, 0, key); } +EXPORT_SYMBOL_GPL(__wake_up_locked_key); /** * __wake_up_sync_key - wake up threads blocked on a waitqueue. @@ -4326,7 +4611,7 @@ EXPORT_SYMBOL(wait_for_completion_interruptible); * This waits for either a completion of a specific task to be signaled or for a * specified timeout to expire. It is interruptible. The timeout is in jiffies. */ -unsigned long __sched +long __sched wait_for_completion_interruptible_timeout(struct completion *x, unsigned long timeout) { @@ -4359,7 +4644,7 @@ EXPORT_SYMBOL(wait_for_completion_killable); * signaled or for a specified timeout to expire. It can be * interrupted by a kill signal. The timeout is in jiffies. */ -unsigned long __sched +long __sched wait_for_completion_killable_timeout(struct completion *x, unsigned long timeout) { @@ -4475,19 +4760,18 @@ EXPORT_SYMBOL(sleep_on_timeout); */ void rt_mutex_setprio(struct task_struct *p, int prio) { - unsigned long flags; int oldprio, on_rq, running; struct rq *rq; const struct sched_class *prev_class; BUG_ON(prio < 0 || prio > MAX_PRIO); - rq = task_rq_lock(p, &flags); + rq = __task_rq_lock(p); trace_sched_pi_setprio(p, prio); oldprio = p->prio; prev_class = p->sched_class; - on_rq = p->se.on_rq; + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) dequeue_task(rq, p, 0); @@ -4503,12 +4787,11 @@ void rt_mutex_setprio(struct task_struct *p, int prio) if (running) p->sched_class->set_curr_task(rq); - if (on_rq) { + if (on_rq) enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0); - check_class_changed(rq, p, prev_class, oldprio, running); - } - task_rq_unlock(rq, &flags); + check_class_changed(rq, p, prev_class, oldprio); + __task_rq_unlock(rq); } #endif @@ -4536,7 +4819,7 @@ void set_user_nice(struct task_struct *p, long nice) p->static_prio = NICE_TO_PRIO(nice); goto out_unlock; } - on_rq = p->se.on_rq; + on_rq = p->on_rq; if (on_rq) dequeue_task(rq, p, 0); @@ -4556,7 +4839,7 @@ void set_user_nice(struct task_struct *p, long nice) resched_task(rq->curr); } out_unlock: - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); } EXPORT_SYMBOL(set_user_nice); @@ -4670,8 +4953,6 @@ static struct task_struct *find_process_by_pid(pid_t pid) static void __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) { - BUG_ON(p->se.on_rq); - p->policy = policy; p->rt_priority = prio; p->normal_prio = normal_prio(p); @@ -4694,14 +4975,17 @@ static bool check_same_owner(struct task_struct *p) rcu_read_lock(); pcred = __task_cred(p); - match = (cred->euid == pcred->euid || - cred->euid == pcred->uid); + if (cred->user->user_ns == pcred->user->user_ns) + match = (cred->euid == pcred->euid || + cred->euid == pcred->uid); + else + match = false; rcu_read_unlock(); return match; } static int __sched_setscheduler(struct task_struct *p, int policy, - struct sched_param *param, bool user) + const struct sched_param *param, bool user) { int retval, oldprio, oldpolicy = -1, on_rq, running; unsigned long flags; @@ -4755,12 +5039,15 @@ recheck: param->sched_priority > rlim_rtprio) return -EPERM; } + /* - * Like positive nice levels, dont allow tasks to - * move out of SCHED_IDLE either: + * Treat SCHED_IDLE as nice 20. Only allow a switch to + * SCHED_NORMAL if the RLIMIT_NICE would normally permit it. */ - if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) - return -EPERM; + if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) { + if (!can_nice(p, TASK_NICE(p))) + return -EPERM; + } /* can't change other user's priorities */ if (!check_same_owner(p)) @@ -4780,21 +5067,29 @@ recheck: /* * make sure no PI-waiters arrive (or leave) while we are * changing the priority of the task: - */ - raw_spin_lock_irqsave(&p->pi_lock, flags); - /* - * To be able to change p->policy safely, the apropriate + * + * To be able to change p->policy safely, the appropriate * runqueue lock must be held. */ - rq = __task_rq_lock(p); + rq = task_rq_lock(p, &flags); /* * Changing the policy of the stop threads its a very bad idea */ if (p == rq->stop) { + task_rq_unlock(rq, p, &flags); + return -EINVAL; + } + + /* + * If not changing anything there's no need to proceed further: + */ + if (unlikely(policy == p->policy && (!rt_policy(policy) || + param->sched_priority == p->rt_priority))) { + __task_rq_unlock(rq); raw_spin_unlock_irqrestore(&p->pi_lock, flags); - return -EINVAL; + return 0; } #ifdef CONFIG_RT_GROUP_SCHED @@ -4804,9 +5099,9 @@ recheck: * assigned. */ if (rt_bandwidth_enabled() && rt_policy(policy) && - task_group(p)->rt_bandwidth.rt_runtime == 0) { - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_group(p)->rt_bandwidth.rt_runtime == 0 && + !task_group_is_autogroup(task_group(p))) { + task_rq_unlock(rq, p, &flags); return -EPERM; } } @@ -4815,11 +5110,10 @@ recheck: /* recheck policy now with rq lock held */ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { policy = oldpolicy = -1; - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + task_rq_unlock(rq, p, &flags); goto recheck; } - on_rq = p->se.on_rq; + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) deactivate_task(rq, p, 0); @@ -4834,13 +5128,11 @@ recheck: if (running) p->sched_class->set_curr_task(rq); - if (on_rq) { + if (on_rq) activate_task(rq, p, 0); - check_class_changed(rq, p, prev_class, oldprio, running); - } - __task_rq_unlock(rq); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); + check_class_changed(rq, p, prev_class, oldprio); + task_rq_unlock(rq, p, &flags); rt_mutex_adjust_pi(p); @@ -4856,7 +5148,7 @@ recheck: * NOTE that the task may be already dead. */ int sched_setscheduler(struct task_struct *p, int policy, - struct sched_param *param) + const struct sched_param *param) { return __sched_setscheduler(p, policy, param, true); } @@ -4874,7 +5166,7 @@ EXPORT_SYMBOL_GPL(sched_setscheduler); * but our caller might not have that capability. */ int sched_setscheduler_nocheck(struct task_struct *p, int policy, - struct sched_param *param) + const struct sched_param *param) { return __sched_setscheduler(p, policy, param, false); } @@ -5020,7 +5312,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) goto out_free_cpus_allowed; } retval = -EPERM; - if (!check_same_owner(p) && !capable(CAP_SYS_NICE)) + if (!check_same_owner(p) && !task_ns_capable(p, CAP_SYS_NICE)) goto out_unlock; retval = security_task_setscheduler(p); @@ -5091,7 +5383,6 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask) { struct task_struct *p; unsigned long flags; - struct rq *rq; int retval; get_online_cpus(); @@ -5106,9 +5397,9 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask) if (retval) goto out_unlock; - rq = task_rq_lock(p, &flags); + raw_spin_lock_irqsave(&p->pi_lock, flags); cpumask_and(mask, &p->cpus_allowed, cpu_online_mask); - task_rq_unlock(rq, &flags); + raw_spin_unlock_irqrestore(&p->pi_lock, flags); out_unlock: rcu_read_unlock(); @@ -5255,6 +5546,67 @@ void __sched yield(void) } EXPORT_SYMBOL(yield); +/** + * yield_to - yield the current processor to another thread in + * your thread group, or accelerate that thread toward the + * processor it's on. + * @p: target task + * @preempt: whether task preemption is allowed or not + * + * It's the caller's job to ensure that the target task struct + * can't go away on us before we can do any checks. + * + * Returns true if we indeed boosted the target task. + */ +bool __sched yield_to(struct task_struct *p, bool preempt) +{ + struct task_struct *curr = current; + struct rq *rq, *p_rq; + unsigned long flags; + bool yielded = 0; + + local_irq_save(flags); + rq = this_rq(); + +again: + p_rq = task_rq(p); + double_rq_lock(rq, p_rq); + while (task_rq(p) != p_rq) { + double_rq_unlock(rq, p_rq); + goto again; + } + + if (!curr->sched_class->yield_to_task) + goto out; + + if (curr->sched_class != p->sched_class) + goto out; + + if (task_running(p_rq, p) || p->state) + goto out; + + yielded = curr->sched_class->yield_to_task(rq, p, preempt); + if (yielded) { + schedstat_inc(rq, yld_count); + /* + * Make p's CPU reschedule; pick_next_entity takes care of + * fairness. + */ + if (preempt && rq != p_rq) + resched_task(p_rq->curr); + } + +out: + double_rq_unlock(rq, p_rq); + local_irq_restore(flags); + + if (yielded) + schedule(); + + return yielded; +} +EXPORT_SYMBOL_GPL(yield_to); + /* * This task is about to go to sleep on IO. Increment rq->nr_iowait so * that process accounting knows that this is a task in IO wait state. @@ -5265,6 +5617,7 @@ void __sched io_schedule(void) delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); current->in_iowait = 1; schedule(); current->in_iowait = 0; @@ -5280,6 +5633,7 @@ long __sched io_schedule_timeout(long timeout) delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); current->in_iowait = 1; ret = schedule_timeout(timeout); current->in_iowait = 0; @@ -5370,7 +5724,7 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, rq = task_rq_lock(p, &flags); time_slice = p->sched_class->get_rr_interval(rq, p); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); rcu_read_unlock(); jiffies_to_timespec(time_slice, &t); @@ -5390,7 +5744,7 @@ void sched_show_task(struct task_struct *p) unsigned state; state = p->state ? __ffs(p->state) + 1 : 0; - printk(KERN_INFO "%-13.13s %c", p->comm, + printk(KERN_INFO "%-15.15s %c", p->comm, state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); #if BITS_PER_LONG == 32 if (state == TASK_RUNNING) @@ -5428,7 +5782,7 @@ void show_state_filter(unsigned long state_filter) do_each_thread(g, p) { /* * reset the NMI-timeout, listing all files on a slow - * console might take alot of time: + * console might take a lot of time: */ touch_nmi_watchdog(); if (!state_filter || (p->state & state_filter)) @@ -5488,22 +5842,19 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) rcu_read_unlock(); rq->curr = rq->idle = idle; -#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) - idle->oncpu = 1; +#if defined(CONFIG_SMP) + idle->on_cpu = 1; #endif raw_spin_unlock_irqrestore(&rq->lock, flags); /* Set the preempt count _outside_ the spinlocks! */ -#if defined(CONFIG_PREEMPT) - task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0); -#else task_thread_info(idle)->preempt_count = 0; -#endif + /* * The idle tasks have their own, simple scheduling class: */ idle->sched_class = &idle_sched_class; - ftrace_graph_init_task(idle); + ftrace_graph_init_idle_task(idle, cpu); } /* @@ -5554,7 +5905,6 @@ static void update_sysctl(void) SET_SYSCTL(sched_min_granularity); SET_SYSCTL(sched_latency); SET_SYSCTL(sched_wakeup_granularity); - SET_SYSCTL(sched_shares_ratelimit); #undef SET_SYSCTL } @@ -5594,26 +5944,17 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) unsigned int dest_cpu; int ret = 0; - /* - * Serialize against TASK_WAKING so that ttwu() and wunt() can - * drop the rq->lock and still rely on ->cpus_allowed. - */ -again: - while (task_is_waking(p)) - cpu_relax(); rq = task_rq_lock(p, &flags); - if (task_is_waking(p)) { - task_rq_unlock(rq, &flags); - goto again; - } + + if (cpumask_equal(&p->cpus_allowed, new_mask)) + goto out; if (!cpumask_intersects(new_mask, cpu_active_mask)) { ret = -EINVAL; goto out; } - if (unlikely((p->flags & PF_THREAD_BOUND) && p != current && - !cpumask_equal(&p->cpus_allowed, new_mask))) { + if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) { ret = -EINVAL; goto out; } @@ -5630,16 +5971,16 @@ again: goto out; dest_cpu = cpumask_any_and(cpu_active_mask, new_mask); - if (migrate_task(p, dest_cpu)) { + if (p->on_rq) { struct migration_arg arg = { p, dest_cpu }; /* Need help from migration thread: drop lock and wait. */ - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); tlb_migrate_finish(p->mm); return 0; } out: - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, p, &flags); return ret; } @@ -5667,6 +6008,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) rq_src = cpu_rq(src_cpu); rq_dest = cpu_rq(dest_cpu); + raw_spin_lock(&p->pi_lock); double_rq_lock(rq_src, rq_dest); /* Already moved. */ if (task_cpu(p) != src_cpu) @@ -5679,7 +6021,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) * If we're not on a rq, the next wake-up will ensure we're * placed properly. */ - if (p->se.on_rq) { + if (p->on_rq) { deactivate_task(rq_src, p, 0); set_task_cpu(p, dest_cpu); activate_task(rq_dest, p, 0); @@ -5689,6 +6031,7 @@ done: ret = 1; fail: double_rq_unlock(rq_src, rq_dest); + raw_spin_unlock(&p->pi_lock); return ret; } @@ -5712,29 +6055,20 @@ static int migration_cpu_stop(void *data) } #ifdef CONFIG_HOTPLUG_CPU + /* - * Figure out where task on dead CPU should go, use force if necessary. + * Ensures that the idle task is using init_mm right before its cpu goes + * offline. */ -void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p) +void idle_task_exit(void) { - struct rq *rq = cpu_rq(dead_cpu); - int needs_cpu, uninitialized_var(dest_cpu); - unsigned long flags; + struct mm_struct *mm = current->active_mm; - local_irq_save(flags); + BUG_ON(cpu_online(smp_processor_id())); - raw_spin_lock(&rq->lock); - needs_cpu = (task_cpu(p) == dead_cpu) && (p->state != TASK_WAKING); - if (needs_cpu) - dest_cpu = select_fallback_rq(dead_cpu, p); - raw_spin_unlock(&rq->lock); - /* - * It can only fail if we race with set_cpus_allowed(), - * in the racer should migrate the task anyway. - */ - if (needs_cpu) - __migrate_task(p, dead_cpu, dest_cpu); - local_irq_restore(flags); + if (mm != &init_mm) + switch_mm(mm, &init_mm, current); + mmdrop(mm); } /* @@ -5747,128 +6081,69 @@ void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p) static void migrate_nr_uninterruptible(struct rq *rq_src) { struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask)); - unsigned long flags; - local_irq_save(flags); - double_rq_lock(rq_src, rq_dest); rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible; rq_src->nr_uninterruptible = 0; - double_rq_unlock(rq_src, rq_dest); - local_irq_restore(flags); -} - -/* Run through task list and migrate tasks from the dead cpu. */ -static void migrate_live_tasks(int src_cpu) -{ - struct task_struct *p, *t; - - read_lock(&tasklist_lock); - - do_each_thread(t, p) { - if (p == current) - continue; - - if (task_cpu(p) == src_cpu) - move_task_off_dead_cpu(src_cpu, p); - } while_each_thread(t, p); - - read_unlock(&tasklist_lock); } /* - * Schedules idle task to be the next runnable task on current CPU. - * It does so by boosting its priority to highest possible. - * Used by CPU offline code. + * remove the tasks which were accounted by rq from calc_load_tasks. */ -void sched_idle_next(void) +static void calc_global_load_remove(struct rq *rq) { - int this_cpu = smp_processor_id(); - struct rq *rq = cpu_rq(this_cpu); - struct task_struct *p = rq->idle; - unsigned long flags; - - /* cpu has to be offline */ - BUG_ON(cpu_online(this_cpu)); - - /* - * Strictly not necessary since rest of the CPUs are stopped by now - * and interrupts disabled on the current cpu. - */ - raw_spin_lock_irqsave(&rq->lock, flags); - - __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1); - - activate_task(rq, p, 0); - - raw_spin_unlock_irqrestore(&rq->lock, flags); + atomic_long_sub(rq->calc_load_active, &calc_load_tasks); + rq->calc_load_active = 0; } /* - * Ensures that the idle task is using init_mm right before its cpu goes - * offline. + * Migrate all tasks from the rq, sleeping tasks will be migrated by + * try_to_wake_up()->select_task_rq(). + * + * Called with rq->lock held even though we'er in stop_machine() and + * there's no concurrency possible, we hold the required locks anyway + * because of lock validation efforts. */ -void idle_task_exit(void) -{ - struct mm_struct *mm = current->active_mm; - - BUG_ON(cpu_online(smp_processor_id())); - - if (mm != &init_mm) - switch_mm(mm, &init_mm, current); - mmdrop(mm); -} - -/* called under rq->lock with disabled interrupts */ -static void migrate_dead(unsigned int dead_cpu, struct task_struct *p) +static void migrate_tasks(unsigned int dead_cpu) { struct rq *rq = cpu_rq(dead_cpu); - - /* Must be exiting, otherwise would be on tasklist. */ - BUG_ON(!p->exit_state); - - /* Cannot have done final schedule yet: would have vanished. */ - BUG_ON(p->state == TASK_DEAD); - - get_task_struct(p); + struct task_struct *next, *stop = rq->stop; + int dest_cpu; /* - * Drop lock around migration; if someone else moves it, - * that's OK. No task can be added to this CPU, so iteration is - * fine. + * Fudge the rq selection such that the below task selection loop + * doesn't get stuck on the currently eligible stop task. + * + * We're currently inside stop_machine() and the rq is either stuck + * in the stop_machine_cpu_stop() loop, or we're executing this code, + * either way we should never end up calling schedule() until we're + * done here. */ - raw_spin_unlock_irq(&rq->lock); - move_task_off_dead_cpu(dead_cpu, p); - raw_spin_lock_irq(&rq->lock); - - put_task_struct(p); -} - -/* release_task() removes task from tasklist, so we won't find dead tasks. */ -static void migrate_dead_tasks(unsigned int dead_cpu) -{ - struct rq *rq = cpu_rq(dead_cpu); - struct task_struct *next; + rq->stop = NULL; for ( ; ; ) { - if (!rq->nr_running) + /* + * There's this thread running, bail when that's the only + * remaining thread. + */ + if (rq->nr_running == 1) break; + next = pick_next_task(rq); - if (!next) - break; + BUG_ON(!next); next->sched_class->put_prev_task(rq, next); - migrate_dead(dead_cpu, next); + /* Find suitable destination for @next, with force if needed. */ + dest_cpu = select_fallback_rq(dead_cpu, next); + raw_spin_unlock(&rq->lock); + + __migrate_task(next, dead_cpu, dest_cpu); + + raw_spin_lock(&rq->lock); } -} -/* - * remove the tasks which were accounted by rq from calc_load_tasks. - */ -static void calc_global_load_remove(struct rq *rq) -{ - atomic_long_sub(rq->calc_load_active, &calc_load_tasks); - rq->calc_load_active = 0; + rq->stop = stop; } + #endif /* CONFIG_HOTPLUG_CPU */ #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) @@ -6078,15 +6353,13 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) unsigned long flags; struct rq *rq = cpu_rq(cpu); - switch (action) { + switch (action & ~CPU_TASKS_FROZEN) { case CPU_UP_PREPARE: - case CPU_UP_PREPARE_FROZEN: rq->calc_load_update = calc_load_update; break; case CPU_ONLINE: - case CPU_ONLINE_FROZEN: /* Update our root-domain */ raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { @@ -6098,33 +6371,26 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) break; #ifdef CONFIG_HOTPLUG_CPU - case CPU_DEAD: - case CPU_DEAD_FROZEN: - migrate_live_tasks(cpu); - /* Idle task back to normal (off runqueue, low prio) */ - raw_spin_lock_irq(&rq->lock); - deactivate_task(rq, rq->idle, 0); - __setscheduler(rq, rq->idle, SCHED_NORMAL, 0); - rq->idle->sched_class = &idle_sched_class; - migrate_dead_tasks(cpu); - raw_spin_unlock_irq(&rq->lock); - migrate_nr_uninterruptible(rq); - BUG_ON(rq->nr_running != 0); - calc_global_load_remove(rq); - break; - case CPU_DYING: - case CPU_DYING_FROZEN: + sched_ttwu_pending(); /* Update our root-domain */ raw_spin_lock_irqsave(&rq->lock, flags); if (rq->rd) { BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); set_rq_offline(rq); } + migrate_tasks(cpu); + BUG_ON(rq->nr_running != 1); /* the migration thread */ raw_spin_unlock_irqrestore(&rq->lock, flags); + + migrate_nr_uninterruptible(rq); + calc_global_load_remove(rq); break; #endif } + + update_max_interval(); + return NOTIFY_OK; } @@ -6185,6 +6451,8 @@ early_initcall(migration_init); #ifdef CONFIG_SMP +static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ + #ifdef CONFIG_SCHED_DEBUG static __read_mostly int sched_domain_debug_enabled; @@ -6280,7 +6548,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, static void sched_domain_debug(struct sched_domain *sd, int cpu) { - cpumask_var_t groupmask; int level = 0; if (!sched_domain_debug_enabled) @@ -6293,20 +6560,14 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu) printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); - if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) { - printk(KERN_DEBUG "Cannot load-balance (out of memory)\n"); - return; - } - for (;;) { - if (sched_domain_debug_one(sd, cpu, level, groupmask)) + if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) break; level++; sd = sd->parent; if (!sd) break; } - free_cpumask_var(groupmask); } #else /* !CONFIG_SCHED_DEBUG */ # define sched_domain_debug(sd, cpu) do { } while (0) @@ -6363,12 +6624,11 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) return 1; } -static void free_rootdomain(struct root_domain *rd) +static void free_rootdomain(struct rcu_head *rcu) { - synchronize_sched(); + struct root_domain *rd = container_of(rcu, struct root_domain, rcu); cpupri_cleanup(&rd->cpupri); - free_cpumask_var(rd->rto_mask); free_cpumask_var(rd->online); free_cpumask_var(rd->span); @@ -6409,7 +6669,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd) raw_spin_unlock_irqrestore(&rq->lock, flags); if (old_rd) - free_rootdomain(old_rd); + call_rcu_sched(&old_rd->rcu, free_rootdomain); } static int init_rootdomain(struct root_domain *rd) @@ -6460,6 +6720,25 @@ static struct root_domain *alloc_rootdomain(void) return rd; } +static void free_sched_domain(struct rcu_head *rcu) +{ + struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); + if (atomic_dec_and_test(&sd->groups->ref)) + kfree(sd->groups); + kfree(sd); +} + +static void destroy_sched_domain(struct sched_domain *sd, int cpu) +{ + call_rcu(&sd->rcu, free_sched_domain); +} + +static void destroy_sched_domains(struct sched_domain *sd, int cpu) +{ + for (; sd; sd = sd->parent) + destroy_sched_domain(sd, cpu); +} + /* * Attach the domain 'sd' to 'cpu' as its base domain. Callers must * hold the hotplug lock. @@ -6470,9 +6749,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; - for (tmp = sd; tmp; tmp = tmp->parent) - tmp->span_weight = cpumask_weight(sched_domain_span(tmp)); - /* Remove the sched domains which do not contribute to scheduling. */ for (tmp = sd; tmp; ) { struct sched_domain *parent = tmp->parent; @@ -6483,12 +6759,15 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) tmp->parent = parent->parent; if (parent->parent) parent->parent->child = tmp; + destroy_sched_domain(parent, cpu); } else tmp = tmp->parent; } if (sd && sd_degenerate(sd)) { + tmp = sd; sd = sd->parent; + destroy_sched_domain(tmp, cpu); if (sd) sd->child = NULL; } @@ -6496,7 +6775,9 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) sched_domain_debug(sd, cpu); rq_attach_root(rq, rd); + tmp = rq->sd; rcu_assign_pointer(rq->sd, sd); + destroy_sched_domains(tmp, cpu); } /* cpus with isolated domains */ @@ -6512,56 +6793,6 @@ static int __init isolated_cpu_setup(char *str) __setup("isolcpus=", isolated_cpu_setup); -/* - * init_sched_build_groups takes the cpumask we wish to span, and a pointer - * to a function which identifies what group(along with sched group) a CPU - * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids - * (due to the fact that we keep track of groups covered with a struct cpumask). - * - * init_sched_build_groups will build a circular linked list of the groups - * covered by the given span, and will set each group's ->cpumask correctly, - * and ->cpu_power to 0. - */ -static void -init_sched_build_groups(const struct cpumask *span, - const struct cpumask *cpu_map, - int (*group_fn)(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, - struct cpumask *tmpmask), - struct cpumask *covered, struct cpumask *tmpmask) -{ - struct sched_group *first = NULL, *last = NULL; - int i; - - cpumask_clear(covered); - - for_each_cpu(i, span) { - struct sched_group *sg; - int group = group_fn(i, cpu_map, &sg, tmpmask); - int j; - - if (cpumask_test_cpu(i, covered)) - continue; - - cpumask_clear(sched_group_cpus(sg)); - sg->cpu_power = 0; - - for_each_cpu(j, span) { - if (group_fn(j, cpu_map, NULL, tmpmask) != group) - continue; - - cpumask_set_cpu(j, covered); - cpumask_set_cpu(j, sched_group_cpus(sg)); - } - if (!first) - first = sg; - if (last) - last->next = sg; - last = sg; - } - last->next = first; -} - #define SD_NODES_PER_DOMAIN 16 #ifdef CONFIG_NUMA @@ -6578,7 +6809,7 @@ init_sched_build_groups(const struct cpumask *span, */ static int find_next_best_node(int node, nodemask_t *used_nodes) { - int i, n, val, min_val, best_node = 0; + int i, n, val, min_val, best_node = -1; min_val = INT_MAX; @@ -6602,7 +6833,8 @@ static int find_next_best_node(int node, nodemask_t *used_nodes) } } - node_set(best_node, *used_nodes); + if (best_node != -1) + node_set(best_node, *used_nodes); return best_node; } @@ -6628,315 +6860,130 @@ static void sched_domain_node_span(int node, struct cpumask *span) for (i = 1; i < SD_NODES_PER_DOMAIN; i++) { int next_node = find_next_best_node(node, &used_nodes); - + if (next_node < 0) + break; cpumask_or(span, span, cpumask_of_node(next_node)); } } + +static const struct cpumask *cpu_node_mask(int cpu) +{ + lockdep_assert_held(&sched_domains_mutex); + + sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask); + + return sched_domains_tmpmask; +} + +static const struct cpumask *cpu_allnodes_mask(int cpu) +{ + return cpu_possible_mask; +} #endif /* CONFIG_NUMA */ -int sched_smt_power_savings = 0, sched_mc_power_savings = 0; +static const struct cpumask *cpu_cpu_mask(int cpu) +{ + return cpumask_of_node(cpu_to_node(cpu)); +} -/* - * The cpus mask in sched_group and sched_domain hangs off the end. - * - * ( See the the comments in include/linux/sched.h:struct sched_group - * and struct sched_domain. ) - */ -struct static_sched_group { - struct sched_group sg; - DECLARE_BITMAP(cpus, CONFIG_NR_CPUS); -}; +int sched_smt_power_savings = 0, sched_mc_power_savings = 0; -struct static_sched_domain { - struct sched_domain sd; - DECLARE_BITMAP(span, CONFIG_NR_CPUS); +struct sd_data { + struct sched_domain **__percpu sd; + struct sched_group **__percpu sg; }; struct s_data { -#ifdef CONFIG_NUMA - int sd_allnodes; - cpumask_var_t domainspan; - cpumask_var_t covered; - cpumask_var_t notcovered; -#endif - cpumask_var_t nodemask; - cpumask_var_t this_sibling_map; - cpumask_var_t this_core_map; - cpumask_var_t this_book_map; - cpumask_var_t send_covered; - cpumask_var_t tmpmask; - struct sched_group **sched_group_nodes; + struct sched_domain ** __percpu sd; struct root_domain *rd; }; enum s_alloc { - sa_sched_groups = 0, sa_rootdomain, - sa_tmpmask, - sa_send_covered, - sa_this_book_map, - sa_this_core_map, - sa_this_sibling_map, - sa_nodemask, - sa_sched_group_nodes, -#ifdef CONFIG_NUMA - sa_notcovered, - sa_covered, - sa_domainspan, -#endif + sa_sd, + sa_sd_storage, sa_none, }; -/* - * SMT sched-domains: - */ -#ifdef CONFIG_SCHED_SMT -static DEFINE_PER_CPU(struct static_sched_domain, cpu_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_groups); - -static int -cpu_to_cpu_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *unused) -{ - if (sg) - *sg = &per_cpu(sched_groups, cpu).sg; - return cpu; -} -#endif /* CONFIG_SCHED_SMT */ +struct sched_domain_topology_level; -/* - * multi-core sched-domains: - */ -#ifdef CONFIG_SCHED_MC -static DEFINE_PER_CPU(struct static_sched_domain, core_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_core); +typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu); +typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); -static int -cpu_to_core_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) -{ - int group; -#ifdef CONFIG_SCHED_SMT - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#else - group = cpu; -#endif - if (sg) - *sg = &per_cpu(sched_group_core, group).sg; - return group; -} -#endif /* CONFIG_SCHED_MC */ +struct sched_domain_topology_level { + sched_domain_init_f init; + sched_domain_mask_f mask; + struct sd_data data; +}; /* - * book sched-domains: + * Assumes the sched_domain tree is fully constructed */ -#ifdef CONFIG_SCHED_BOOK -static DEFINE_PER_CPU(struct static_sched_domain, book_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_book); - -static int -cpu_to_book_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) +static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg) { - int group = cpu; -#ifdef CONFIG_SCHED_MC - cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_SMT) - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#endif - if (sg) - *sg = &per_cpu(sched_group_book, group).sg; - return group; -} -#endif /* CONFIG_SCHED_BOOK */ + struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); + struct sched_domain *child = sd->child; -static DEFINE_PER_CPU(struct static_sched_domain, phys_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_phys); + if (child) + cpu = cpumask_first(sched_domain_span(child)); -static int -cpu_to_phys_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, struct cpumask *mask) -{ - int group; -#ifdef CONFIG_SCHED_BOOK - cpumask_and(mask, cpu_book_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_MC) - cpumask_and(mask, cpu_coregroup_mask(cpu), cpu_map); - group = cpumask_first(mask); -#elif defined(CONFIG_SCHED_SMT) - cpumask_and(mask, topology_thread_cpumask(cpu), cpu_map); - group = cpumask_first(mask); -#else - group = cpu; -#endif if (sg) - *sg = &per_cpu(sched_group_phys, group).sg; - return group; + *sg = *per_cpu_ptr(sdd->sg, cpu); + + return cpu; } -#ifdef CONFIG_NUMA /* - * The init_sched_build_groups can't handle what we want to do with node - * groups, so roll our own. Now each node has its own list of groups which - * gets dynamically allocated. + * build_sched_groups takes the cpumask we wish to span, and a pointer + * to a function which identifies what group(along with sched group) a CPU + * belongs to. The return value of group_fn must be a >= 0 and < nr_cpu_ids + * (due to the fact that we keep track of groups covered with a struct cpumask). + * + * build_sched_groups will build a circular linked list of the groups + * covered by the given span, and will set each group's ->cpumask correctly, + * and ->cpu_power to 0. */ -static DEFINE_PER_CPU(struct static_sched_domain, node_domains); -static struct sched_group ***sched_group_nodes_bycpu; - -static DEFINE_PER_CPU(struct static_sched_domain, allnodes_domains); -static DEFINE_PER_CPU(struct static_sched_group, sched_group_allnodes); - -static int cpu_to_allnodes_group(int cpu, const struct cpumask *cpu_map, - struct sched_group **sg, - struct cpumask *nodemask) -{ - int group; - - cpumask_and(nodemask, cpumask_of_node(cpu_to_node(cpu)), cpu_map); - group = cpumask_first(nodemask); - - if (sg) - *sg = &per_cpu(sched_group_allnodes, group).sg; - return group; -} - -static void init_numa_sched_groups_power(struct sched_group *group_head) -{ - struct sched_group *sg = group_head; - int j; - - if (!sg) - return; - do { - for_each_cpu(j, sched_group_cpus(sg)) { - struct sched_domain *sd; - - sd = &per_cpu(phys_domains, j).sd; - if (j != group_first_cpu(sd->groups)) { - /* - * Only add "power" once for each - * physical package. - */ - continue; - } - - sg->cpu_power += sd->groups->cpu_power; - } - sg = sg->next; - } while (sg != group_head); -} - -static int build_numa_sched_groups(struct s_data *d, - const struct cpumask *cpu_map, int num) +static void +build_sched_groups(struct sched_domain *sd) { - struct sched_domain *sd; - struct sched_group *sg, *prev; - int n, j; - - cpumask_clear(d->covered); - cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map); - if (cpumask_empty(d->nodemask)) { - d->sched_group_nodes[num] = NULL; - goto out; - } - - sched_domain_node_span(num, d->domainspan); - cpumask_and(d->domainspan, d->domainspan, cpu_map); - - sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), - GFP_KERNEL, num); - if (!sg) { - printk(KERN_WARNING "Can not alloc domain group for node %d\n", - num); - return -ENOMEM; - } - d->sched_group_nodes[num] = sg; - - for_each_cpu(j, d->nodemask) { - sd = &per_cpu(node_domains, j).sd; - sd->groups = sg; - } - - sg->cpu_power = 0; - cpumask_copy(sched_group_cpus(sg), d->nodemask); - sg->next = sg; - cpumask_or(d->covered, d->covered, d->nodemask); + struct sched_group *first = NULL, *last = NULL; + struct sd_data *sdd = sd->private; + const struct cpumask *span = sched_domain_span(sd); + struct cpumask *covered; + int i; - prev = sg; - for (j = 0; j < nr_node_ids; j++) { - n = (num + j) % nr_node_ids; - cpumask_complement(d->notcovered, d->covered); - cpumask_and(d->tmpmask, d->notcovered, cpu_map); - cpumask_and(d->tmpmask, d->tmpmask, d->domainspan); - if (cpumask_empty(d->tmpmask)) - break; - cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n)); - if (cpumask_empty(d->tmpmask)) - continue; - sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), - GFP_KERNEL, num); - if (!sg) { - printk(KERN_WARNING - "Can not alloc domain group for node %d\n", j); - return -ENOMEM; - } - sg->cpu_power = 0; - cpumask_copy(sched_group_cpus(sg), d->tmpmask); - sg->next = prev->next; - cpumask_or(d->covered, d->covered, d->tmpmask); - prev->next = sg; - prev = sg; - } -out: - return 0; -} -#endif /* CONFIG_NUMA */ + lockdep_assert_held(&sched_domains_mutex); + covered = sched_domains_tmpmask; -#ifdef CONFIG_NUMA -/* Free memory allocated for various sched_group structures */ -static void free_sched_groups(const struct cpumask *cpu_map, - struct cpumask *nodemask) -{ - int cpu, i; + cpumask_clear(covered); - for_each_cpu(cpu, cpu_map) { - struct sched_group **sched_group_nodes - = sched_group_nodes_bycpu[cpu]; + for_each_cpu(i, span) { + struct sched_group *sg; + int group = get_group(i, sdd, &sg); + int j; - if (!sched_group_nodes) + if (cpumask_test_cpu(i, covered)) continue; - for (i = 0; i < nr_node_ids; i++) { - struct sched_group *oldsg, *sg = sched_group_nodes[i]; + cpumask_clear(sched_group_cpus(sg)); + sg->cpu_power = 0; - cpumask_and(nodemask, cpumask_of_node(i), cpu_map); - if (cpumask_empty(nodemask)) + for_each_cpu(j, span) { + if (get_group(j, sdd, NULL) != group) continue; - if (sg == NULL) - continue; - sg = sg->next; -next_sg: - oldsg = sg; - sg = sg->next; - kfree(oldsg); - if (oldsg != sched_group_nodes[i]) - goto next_sg; + cpumask_set_cpu(j, covered); + cpumask_set_cpu(j, sched_group_cpus(sg)); } - kfree(sched_group_nodes); - sched_group_nodes_bycpu[cpu] = NULL; + + if (!first) + first = sg; + if (last) + last->next = sg; + last = sg; } + last->next = first; } -#else /* !CONFIG_NUMA */ -static void free_sched_groups(const struct cpumask *cpu_map, - struct cpumask *nodemask) -{ -} -#endif /* CONFIG_NUMA */ /* * Initialize sched groups cpu_power. @@ -6950,46 +6997,14 @@ static void free_sched_groups(const struct cpumask *cpu_map, */ static void init_sched_groups_power(int cpu, struct sched_domain *sd) { - struct sched_domain *child; - struct sched_group *group; - long power; - int weight; - WARN_ON(!sd || !sd->groups); if (cpu != group_first_cpu(sd->groups)) return; - child = sd->child; - - sd->groups->cpu_power = 0; + sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups)); - if (!child) { - power = SCHED_LOAD_SCALE; - weight = cpumask_weight(sched_domain_span(sd)); - /* - * SMT siblings share the power of a single core. - * Usually multiple threads get a better yield out of - * that one core than a single thread would have, - * reflect that in sd->smt_gain. - */ - if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) { - power *= sd->smt_gain; - power /= weight; - power >>= SCHED_LOAD_SHIFT; - } - sd->groups->cpu_power += power; - return; - } - - /* - * Add cpu_power of each child group to this groups cpu_power. - */ - group = child->groups; - do { - sd->groups->cpu_power += group->cpu_power; - group = group->next; - } while (group != child->groups); + update_group_power(sd, cpu); } /* @@ -7003,15 +7018,15 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) # define SD_INIT_NAME(sd, type) do { } while (0) #endif -#define SD_INIT(sd, type) sd_init_##type(sd) - -#define SD_INIT_FUNC(type) \ -static noinline void sd_init_##type(struct sched_domain *sd) \ -{ \ - memset(sd, 0, sizeof(*sd)); \ - *sd = SD_##type##_INIT; \ - sd->level = SD_LV_##type; \ - SD_INIT_NAME(sd, type); \ +#define SD_INIT_FUNC(type) \ +static noinline struct sched_domain * \ +sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \ +{ \ + struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \ + *sd = SD_##type##_INIT; \ + SD_INIT_NAME(sd, type); \ + sd->private = &tl->data; \ + return sd; \ } SD_INIT_FUNC(CPU) @@ -7030,13 +7045,14 @@ SD_INIT_FUNC(CPU) #endif static int default_relax_domain_level = -1; +int sched_domain_level_max; static int __init setup_relax_domain_level(char *str) { unsigned long val; val = simple_strtoul(str, NULL, 0); - if (val < SD_LV_MAX) + if (val < sched_domain_level_max) default_relax_domain_level = val; return 1; @@ -7064,37 +7080,20 @@ static void set_domain_attribute(struct sched_domain *sd, } } +static void __sdt_free(const struct cpumask *cpu_map); +static int __sdt_alloc(const struct cpumask *cpu_map); + static void __free_domain_allocs(struct s_data *d, enum s_alloc what, const struct cpumask *cpu_map) { switch (what) { - case sa_sched_groups: - free_sched_groups(cpu_map, d->tmpmask); /* fall through */ - d->sched_group_nodes = NULL; case sa_rootdomain: - free_rootdomain(d->rd); /* fall through */ - case sa_tmpmask: - free_cpumask_var(d->tmpmask); /* fall through */ - case sa_send_covered: - free_cpumask_var(d->send_covered); /* fall through */ - case sa_this_book_map: - free_cpumask_var(d->this_book_map); /* fall through */ - case sa_this_core_map: - free_cpumask_var(d->this_core_map); /* fall through */ - case sa_this_sibling_map: - free_cpumask_var(d->this_sibling_map); /* fall through */ - case sa_nodemask: - free_cpumask_var(d->nodemask); /* fall through */ - case sa_sched_group_nodes: -#ifdef CONFIG_NUMA - kfree(d->sched_group_nodes); /* fall through */ - case sa_notcovered: - free_cpumask_var(d->notcovered); /* fall through */ - case sa_covered: - free_cpumask_var(d->covered); /* fall through */ - case sa_domainspan: - free_cpumask_var(d->domainspan); /* fall through */ -#endif + if (!atomic_read(&d->rd->refcount)) + free_rootdomain(&d->rd->rcu); /* fall through */ + case sa_sd: + free_percpu(d->sd); /* fall through */ + case sa_sd_storage: + __sdt_free(cpu_map); /* fall through */ case sa_none: break; } @@ -7103,308 +7102,212 @@ static void __free_domain_allocs(struct s_data *d, enum s_alloc what, static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, const struct cpumask *cpu_map) { -#ifdef CONFIG_NUMA - if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL)) - return sa_none; - if (!alloc_cpumask_var(&d->covered, GFP_KERNEL)) - return sa_domainspan; - if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL)) - return sa_covered; - /* Allocate the per-node list of sched groups */ - d->sched_group_nodes = kcalloc(nr_node_ids, - sizeof(struct sched_group *), GFP_KERNEL); - if (!d->sched_group_nodes) { - printk(KERN_WARNING "Can not alloc sched group node list\n"); - return sa_notcovered; - } - sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes; -#endif - if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL)) - return sa_sched_group_nodes; - if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL)) - return sa_nodemask; - if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL)) - return sa_this_sibling_map; - if (!alloc_cpumask_var(&d->this_book_map, GFP_KERNEL)) - return sa_this_core_map; - if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL)) - return sa_this_book_map; - if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL)) - return sa_send_covered; + memset(d, 0, sizeof(*d)); + + if (__sdt_alloc(cpu_map)) + return sa_sd_storage; + d->sd = alloc_percpu(struct sched_domain *); + if (!d->sd) + return sa_sd_storage; d->rd = alloc_rootdomain(); - if (!d->rd) { - printk(KERN_WARNING "Cannot alloc root domain\n"); - return sa_tmpmask; - } + if (!d->rd) + return sa_sd; return sa_rootdomain; } -static struct sched_domain *__build_numa_sched_domains(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i) +/* + * NULL the sd_data elements we've used to build the sched_domain and + * sched_group structure so that the subsequent __free_domain_allocs() + * will not free the data we're using. + */ +static void claim_allocations(int cpu, struct sched_domain *sd) { - struct sched_domain *sd = NULL; -#ifdef CONFIG_NUMA - struct sched_domain *parent; - - d->sd_allnodes = 0; - if (cpumask_weight(cpu_map) > - SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) { - sd = &per_cpu(allnodes_domains, i).sd; - SD_INIT(sd, ALLNODES); - set_domain_attribute(sd, attr); - cpumask_copy(sched_domain_span(sd), cpu_map); - cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask); - d->sd_allnodes = 1; - } - parent = sd; - - sd = &per_cpu(node_domains, i).sd; - SD_INIT(sd, NODE); - set_domain_attribute(sd, attr); - sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd)); - sd->parent = parent; - if (parent) - parent->child = sd; - cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map); -#endif - return sd; -} + struct sd_data *sdd = sd->private; + struct sched_group *sg = sd->groups; -static struct sched_domain *__build_cpu_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd; - sd = &per_cpu(phys_domains, i).sd; - SD_INIT(sd, CPU); - set_domain_attribute(sd, attr); - cpumask_copy(sched_domain_span(sd), d->nodemask); - sd->parent = parent; - if (parent) - parent->child = sd; - cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask); - return sd; -} + WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); + *per_cpu_ptr(sdd->sd, cpu) = NULL; -static struct sched_domain *__build_book_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_BOOK - sd = &per_cpu(book_domains, i).sd; - SD_INIT(sd, BOOK); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, cpu_book_mask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_book_group(i, cpu_map, &sd->groups, d->tmpmask); -#endif - return sd; + if (cpu == cpumask_first(sched_group_cpus(sg))) { + WARN_ON_ONCE(*per_cpu_ptr(sdd->sg, cpu) != sg); + *per_cpu_ptr(sdd->sg, cpu) = NULL; + } } -static struct sched_domain *__build_mc_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) +#ifdef CONFIG_SCHED_SMT +static const struct cpumask *cpu_smt_mask(int cpu) { - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_MC - sd = &per_cpu(core_domains, i).sd; - SD_INIT(sd, MC); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask); -#endif - return sd; + return topology_thread_cpumask(cpu); } - -static struct sched_domain *__build_smt_sched_domain(struct s_data *d, - const struct cpumask *cpu_map, struct sched_domain_attr *attr, - struct sched_domain *parent, int i) -{ - struct sched_domain *sd = parent; -#ifdef CONFIG_SCHED_SMT - sd = &per_cpu(cpu_domains, i).sd; - SD_INIT(sd, SIBLING); - set_domain_attribute(sd, attr); - cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i)); - sd->parent = parent; - parent->child = sd; - cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask); #endif - return sd; -} -static void build_sched_groups(struct s_data *d, enum sched_domain_level l, - const struct cpumask *cpu_map, int cpu) -{ - switch (l) { +/* + * Topology list, bottom-up. + */ +static struct sched_domain_topology_level default_topology[] = { #ifdef CONFIG_SCHED_SMT - case SD_LV_SIBLING: /* set up CPU (sibling) groups */ - cpumask_and(d->this_sibling_map, cpu_map, - topology_thread_cpumask(cpu)); - if (cpu == cpumask_first(d->this_sibling_map)) - init_sched_build_groups(d->this_sibling_map, cpu_map, - &cpu_to_cpu_group, - d->send_covered, d->tmpmask); - break; + { sd_init_SIBLING, cpu_smt_mask, }, #endif #ifdef CONFIG_SCHED_MC - case SD_LV_MC: /* set up multi-core groups */ - cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu)); - if (cpu == cpumask_first(d->this_core_map)) - init_sched_build_groups(d->this_core_map, cpu_map, - &cpu_to_core_group, - d->send_covered, d->tmpmask); - break; + { sd_init_MC, cpu_coregroup_mask, }, #endif #ifdef CONFIG_SCHED_BOOK - case SD_LV_BOOK: /* set up book groups */ - cpumask_and(d->this_book_map, cpu_map, cpu_book_mask(cpu)); - if (cpu == cpumask_first(d->this_book_map)) - init_sched_build_groups(d->this_book_map, cpu_map, - &cpu_to_book_group, - d->send_covered, d->tmpmask); - break; + { sd_init_BOOK, cpu_book_mask, }, #endif - case SD_LV_CPU: /* set up physical groups */ - cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map); - if (!cpumask_empty(d->nodemask)) - init_sched_build_groups(d->nodemask, cpu_map, - &cpu_to_phys_group, - d->send_covered, d->tmpmask); - break; + { sd_init_CPU, cpu_cpu_mask, }, #ifdef CONFIG_NUMA - case SD_LV_ALLNODES: - init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group, - d->send_covered, d->tmpmask); - break; + { sd_init_NODE, cpu_node_mask, }, + { sd_init_ALLNODES, cpu_allnodes_mask, }, #endif - default: - break; + { NULL, }, +}; + +static struct sched_domain_topology_level *sched_domain_topology = default_topology; + +static int __sdt_alloc(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + sdd->sd = alloc_percpu(struct sched_domain *); + if (!sdd->sd) + return -ENOMEM; + + sdd->sg = alloc_percpu(struct sched_group *); + if (!sdd->sg) + return -ENOMEM; + + for_each_cpu(j, cpu_map) { + struct sched_domain *sd; + struct sched_group *sg; + + sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sd) + return -ENOMEM; + + *per_cpu_ptr(sdd->sd, j) = sd; + + sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), + GFP_KERNEL, cpu_to_node(j)); + if (!sg) + return -ENOMEM; + + *per_cpu_ptr(sdd->sg, j) = sg; + } } + + return 0; +} + +static void __sdt_free(const struct cpumask *cpu_map) +{ + struct sched_domain_topology_level *tl; + int j; + + for (tl = sched_domain_topology; tl->init; tl++) { + struct sd_data *sdd = &tl->data; + + for_each_cpu(j, cpu_map) { + kfree(*per_cpu_ptr(sdd->sd, j)); + kfree(*per_cpu_ptr(sdd->sg, j)); + } + free_percpu(sdd->sd); + free_percpu(sdd->sg); + } +} + +struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, + struct s_data *d, const struct cpumask *cpu_map, + struct sched_domain_attr *attr, struct sched_domain *child, + int cpu) +{ + struct sched_domain *sd = tl->init(tl, cpu); + if (!sd) + return child; + + set_domain_attribute(sd, attr); + cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); + if (child) { + sd->level = child->level + 1; + sched_domain_level_max = max(sched_domain_level_max, sd->level); + child->parent = sd; + } + sd->child = child; + + return sd; } /* * Build sched domains for a given set of cpus and attach the sched domains * to the individual cpus */ -static int __build_sched_domains(const struct cpumask *cpu_map, - struct sched_domain_attr *attr) +static int build_sched_domains(const struct cpumask *cpu_map, + struct sched_domain_attr *attr) { enum s_alloc alloc_state = sa_none; - struct s_data d; struct sched_domain *sd; - int i; -#ifdef CONFIG_NUMA - d.sd_allnodes = 0; -#endif + struct s_data d; + int i, ret = -ENOMEM; alloc_state = __visit_domain_allocation_hell(&d, cpu_map); if (alloc_state != sa_rootdomain) goto error; - alloc_state = sa_sched_groups; - - /* - * Set up domains for cpus specified by the cpu_map. - */ - for_each_cpu(i, cpu_map) { - cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)), - cpu_map); - - sd = __build_numa_sched_domains(&d, cpu_map, attr, i); - sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_book_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i); - sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i); - } + /* Set up domains for cpus specified by the cpu_map. */ for_each_cpu(i, cpu_map) { - build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i); - build_sched_groups(&d, SD_LV_BOOK, cpu_map, i); - build_sched_groups(&d, SD_LV_MC, cpu_map, i); - } + struct sched_domain_topology_level *tl; - /* Set up physical groups */ - for (i = 0; i < nr_node_ids; i++) - build_sched_groups(&d, SD_LV_CPU, cpu_map, i); + sd = NULL; + for (tl = sched_domain_topology; tl->init; tl++) + sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); -#ifdef CONFIG_NUMA - /* Set up node groups */ - if (d.sd_allnodes) - build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0); + while (sd->child) + sd = sd->child; - for (i = 0; i < nr_node_ids; i++) - if (build_numa_sched_groups(&d, cpu_map, i)) - goto error; -#endif - - /* Calculate CPU power for physical packages and nodes */ -#ifdef CONFIG_SCHED_SMT - for_each_cpu(i, cpu_map) { - sd = &per_cpu(cpu_domains, i).sd; - init_sched_groups_power(i, sd); + *per_cpu_ptr(d.sd, i) = sd; } -#endif -#ifdef CONFIG_SCHED_MC - for_each_cpu(i, cpu_map) { - sd = &per_cpu(core_domains, i).sd; - init_sched_groups_power(i, sd); - } -#endif -#ifdef CONFIG_SCHED_BOOK - for_each_cpu(i, cpu_map) { - sd = &per_cpu(book_domains, i).sd; - init_sched_groups_power(i, sd); - } -#endif + /* Build the groups for the domains */ for_each_cpu(i, cpu_map) { - sd = &per_cpu(phys_domains, i).sd; - init_sched_groups_power(i, sd); - } + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + sd->span_weight = cpumask_weight(sched_domain_span(sd)); + get_group(i, sd->private, &sd->groups); + atomic_inc(&sd->groups->ref); -#ifdef CONFIG_NUMA - for (i = 0; i < nr_node_ids; i++) - init_numa_sched_groups_power(d.sched_group_nodes[i]); + if (i != cpumask_first(sched_domain_span(sd))) + continue; - if (d.sd_allnodes) { - struct sched_group *sg; + build_sched_groups(sd); + } + } + + /* Calculate CPU power for physical packages and nodes */ + for (i = nr_cpumask_bits-1; i >= 0; i--) { + if (!cpumask_test_cpu(i, cpu_map)) + continue; - cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg, - d.tmpmask); - init_numa_sched_groups_power(sg); + for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { + claim_allocations(i, sd); + init_sched_groups_power(i, sd); + } } -#endif /* Attach the domains */ + rcu_read_lock(); for_each_cpu(i, cpu_map) { -#ifdef CONFIG_SCHED_SMT - sd = &per_cpu(cpu_domains, i).sd; -#elif defined(CONFIG_SCHED_MC) - sd = &per_cpu(core_domains, i).sd; -#elif defined(CONFIG_SCHED_BOOK) - sd = &per_cpu(book_domains, i).sd; -#else - sd = &per_cpu(phys_domains, i).sd; -#endif + sd = *per_cpu_ptr(d.sd, i); cpu_attach_domain(sd, d.rd, i); } + rcu_read_unlock(); - d.sched_group_nodes = NULL; /* don't free this we still need it */ - __free_domain_allocs(&d, sa_tmpmask, cpu_map); - return 0; - + ret = 0; error: __free_domain_allocs(&d, alloc_state, cpu_map); - return -ENOMEM; -} - -static int build_sched_domains(const struct cpumask *cpu_map) -{ - return __build_sched_domains(cpu_map, NULL); + return ret; } static cpumask_var_t *doms_cur; /* current sched domains */ @@ -7459,7 +7362,7 @@ void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) * For now this just excludes isolated cpus, but could be used to * exclude other special cases in the future. */ -static int arch_init_sched_domains(const struct cpumask *cpu_map) +static int init_sched_domains(const struct cpumask *cpu_map) { int err; @@ -7470,32 +7373,24 @@ static int arch_init_sched_domains(const struct cpumask *cpu_map) doms_cur = &fallback_doms; cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); dattr_cur = NULL; - err = build_sched_domains(doms_cur[0]); + err = build_sched_domains(doms_cur[0], NULL); register_sched_domain_sysctl(); return err; } -static void arch_destroy_sched_domains(const struct cpumask *cpu_map, - struct cpumask *tmpmask) -{ - free_sched_groups(cpu_map, tmpmask); -} - /* * Detach sched domains from a group of cpus specified in cpu_map * These cpus will now be attached to the NULL domain */ static void detach_destroy_domains(const struct cpumask *cpu_map) { - /* Save because hotplug lock held. */ - static DECLARE_BITMAP(tmpmask, CONFIG_NR_CPUS); int i; + rcu_read_lock(); for_each_cpu(i, cpu_map) cpu_attach_domain(NULL, &def_root_domain, i); - synchronize_sched(); - arch_destroy_sched_domains(cpu_map, to_cpumask(tmpmask)); + rcu_read_unlock(); } /* handle null as "default" */ @@ -7584,8 +7479,7 @@ match1: goto match2; } /* no match - add a new doms_new */ - __build_sched_domains(doms_new[i], - dattr_new ? dattr_new + i : NULL); + build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); match2: ; } @@ -7604,7 +7498,7 @@ match2: } #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) -static void arch_reinit_sched_domains(void) +static void reinit_sched_domains(void) { get_online_cpus(); @@ -7637,7 +7531,7 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) else sched_mc_power_savings = level; - arch_reinit_sched_domains(); + reinit_sched_domains(); return count; } @@ -7756,14 +7650,9 @@ void __init sched_init_smp(void) alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); alloc_cpumask_var(&fallback_doms, GFP_KERNEL); -#if defined(CONFIG_NUMA) - sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **), - GFP_KERNEL); - BUG_ON(sched_group_nodes_bycpu == NULL); -#endif get_online_cpus(); mutex_lock(&sched_domains_mutex); - arch_init_sched_domains(cpu_active_mask); + init_sched_domains(cpu_active_mask); cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map); if (cpumask_empty(non_isolated_cpus)) cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); @@ -7808,6 +7697,10 @@ static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq) INIT_LIST_HEAD(&cfs_rq->tasks); #ifdef CONFIG_FAIR_GROUP_SCHED cfs_rq->rq = rq; + /* allow initial update_cfs_load() to truncate */ +#ifdef CONFIG_SMP + cfs_rq->load_stamp = 1; +#endif #endif cfs_rq->min_vruntime = (u64)(-(1LL << 20)); } @@ -7850,18 +7743,16 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) #ifdef CONFIG_FAIR_GROUP_SCHED static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, - struct sched_entity *se, int cpu, int add, + struct sched_entity *se, int cpu, struct sched_entity *parent) { struct rq *rq = cpu_rq(cpu); tg->cfs_rq[cpu] = cfs_rq; init_cfs_rq(cfs_rq, rq); cfs_rq->tg = tg; - if (add) - list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); tg->se[cpu] = se; - /* se could be NULL for init_task_group */ + /* se could be NULL for root_task_group */ if (!se) return; @@ -7871,15 +7762,14 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, se->cfs_rq = parent->my_q; se->my_q = cfs_rq; - se->load.weight = tg->shares; - se->load.inv_weight = 0; + update_load_set(&se->load, 0); se->parent = parent; } #endif #ifdef CONFIG_RT_GROUP_SCHED static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, - struct sched_rt_entity *rt_se, int cpu, int add, + struct sched_rt_entity *rt_se, int cpu, struct sched_rt_entity *parent) { struct rq *rq = cpu_rq(cpu); @@ -7888,8 +7778,6 @@ static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, init_rt_rq(rt_rq, rq); rt_rq->tg = tg; rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime; - if (add) - list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list); tg->rt_se[cpu] = rt_se; if (!rt_se) @@ -7924,18 +7812,18 @@ void __init sched_init(void) ptr = (unsigned long)kzalloc(alloc_size, GFP_NOWAIT); #ifdef CONFIG_FAIR_GROUP_SCHED - init_task_group.se = (struct sched_entity **)ptr; + root_task_group.se = (struct sched_entity **)ptr; ptr += nr_cpu_ids * sizeof(void **); - init_task_group.cfs_rq = (struct cfs_rq **)ptr; + root_task_group.cfs_rq = (struct cfs_rq **)ptr; ptr += nr_cpu_ids * sizeof(void **); #endif /* CONFIG_FAIR_GROUP_SCHED */ #ifdef CONFIG_RT_GROUP_SCHED - init_task_group.rt_se = (struct sched_rt_entity **)ptr; + root_task_group.rt_se = (struct sched_rt_entity **)ptr; ptr += nr_cpu_ids * sizeof(void **); - init_task_group.rt_rq = (struct rt_rq **)ptr; + root_task_group.rt_rq = (struct rt_rq **)ptr; ptr += nr_cpu_ids * sizeof(void **); #endif /* CONFIG_RT_GROUP_SCHED */ @@ -7955,20 +7843,16 @@ void __init sched_init(void) global_rt_period(), global_rt_runtime()); #ifdef CONFIG_RT_GROUP_SCHED - init_rt_bandwidth(&init_task_group.rt_bandwidth, + init_rt_bandwidth(&root_task_group.rt_bandwidth, global_rt_period(), global_rt_runtime()); #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_CGROUP_SCHED - list_add(&init_task_group.list, &task_groups); - INIT_LIST_HEAD(&init_task_group.children); - + list_add(&root_task_group.list, &task_groups); + INIT_LIST_HEAD(&root_task_group.children); + autogroup_init(&init_task); #endif /* CONFIG_CGROUP_SCHED */ -#if defined CONFIG_FAIR_GROUP_SCHED && defined CONFIG_SMP - update_shares_data = __alloc_percpu(nr_cpu_ids * sizeof(unsigned long), - __alignof__(unsigned long)); -#endif for_each_possible_cpu(i) { struct rq *rq; @@ -7980,38 +7864,34 @@ void __init sched_init(void) init_cfs_rq(&rq->cfs, rq); init_rt_rq(&rq->rt, rq); #ifdef CONFIG_FAIR_GROUP_SCHED - init_task_group.shares = init_task_group_load; + root_task_group.shares = root_task_group_load; INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); -#ifdef CONFIG_CGROUP_SCHED /* - * How much cpu bandwidth does init_task_group get? + * How much cpu bandwidth does root_task_group get? * * In case of task-groups formed thr' the cgroup filesystem, it * gets 100% of the cpu resources in the system. This overall * system cpu resource is divided among the tasks of - * init_task_group and its child task-groups in a fair manner, + * root_task_group and its child task-groups in a fair manner, * based on each entity's (task or task-group's) weight * (se->load.weight). * - * In other words, if init_task_group has 10 tasks of weight + * In other words, if root_task_group has 10 tasks of weight * 1024) and two child groups A0 and A1 (of weight 1024 each), * then A0's share of the cpu resource is: * * A0's bandwidth = 1024 / (10*1024 + 1024 + 1024) = 8.33% * - * We achieve this by letting init_task_group's tasks sit - * directly in rq->cfs (i.e init_task_group->se[] = NULL). + * We achieve this by letting root_task_group's tasks sit + * directly in rq->cfs (i.e root_task_group->se[] = NULL). */ - init_tg_cfs_entry(&init_task_group, &rq->cfs, NULL, i, 1, NULL); -#endif + init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL); #endif /* CONFIG_FAIR_GROUP_SCHED */ rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime; #ifdef CONFIG_RT_GROUP_SCHED INIT_LIST_HEAD(&rq->leaf_rt_rq_list); -#ifdef CONFIG_CGROUP_SCHED - init_tg_rt_entry(&init_task_group, &rq->rt, NULL, i, 1, NULL); -#endif + init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, NULL); #endif for (j = 0; j < CPU_LOAD_IDX_MAX; j++) @@ -8079,6 +7959,7 @@ void __init sched_init(void) /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */ zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT); #ifdef CONFIG_SMP + zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); #ifdef CONFIG_NO_HZ zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT); @@ -8091,8 +7972,6 @@ void __init sched_init(void) zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); #endif /* SMP */ - perf_event_init(); - scheduler_running = 1; } @@ -8101,7 +7980,7 @@ static inline int preempt_count_equals(int preempt_offset) { int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); - return (nested == PREEMPT_INATOMIC_BASE + preempt_offset); + return (nested == preempt_offset); } void __might_sleep(const char *file, int line, int preempt_offset) @@ -8136,9 +8015,11 @@ EXPORT_SYMBOL(__might_sleep); #ifdef CONFIG_MAGIC_SYSRQ static void normalize_task(struct rq *rq, struct task_struct *p) { + const struct sched_class *prev_class = p->sched_class; + int old_prio = p->prio; int on_rq; - on_rq = p->se.on_rq; + on_rq = p->on_rq; if (on_rq) deactivate_task(rq, p, 0); __setscheduler(rq, p, SCHED_NORMAL, 0); @@ -8146,6 +8027,8 @@ static void normalize_task(struct rq *rq, struct task_struct *p) activate_task(rq, p, 0); resched_task(rq->curr); } + + check_class_changed(rq, p, prev_class, old_prio); } void normalize_rt_tasks(void) @@ -8261,7 +8144,6 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) { struct cfs_rq *cfs_rq; struct sched_entity *se; - struct rq *rq; int i; tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL); @@ -8274,8 +8156,6 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) tg->shares = NICE_0_LOAD; for_each_possible_cpu(i) { - rq = cpu_rq(i); - cfs_rq = kzalloc_node(sizeof(struct cfs_rq), GFP_KERNEL, cpu_to_node(i)); if (!cfs_rq) @@ -8286,7 +8166,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) if (!se) goto err_free_rq; - init_tg_cfs_entry(tg, cfs_rq, se, i, 0, parent->se[i]); + init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]); } return 1; @@ -8297,15 +8177,21 @@ err: return 0; } -static inline void register_fair_sched_group(struct task_group *tg, int cpu) -{ - list_add_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list, - &cpu_rq(cpu)->leaf_cfs_rq_list); -} - static inline void unregister_fair_sched_group(struct task_group *tg, int cpu) { - list_del_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list); + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + /* + * Only empty task groups can be destroyed; so we can speculatively + * check on_list without danger of it being re-added. + */ + if (!tg->cfs_rq[cpu]->on_list) + return; + + raw_spin_lock_irqsave(&rq->lock, flags); + list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); + raw_spin_unlock_irqrestore(&rq->lock, flags); } #else /* !CONFG_FAIR_GROUP_SCHED */ static inline void free_fair_sched_group(struct task_group *tg) @@ -8318,10 +8204,6 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) return 1; } -static inline void register_fair_sched_group(struct task_group *tg, int cpu) -{ -} - static inline void unregister_fair_sched_group(struct task_group *tg, int cpu) { } @@ -8350,7 +8232,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) { struct rt_rq *rt_rq; struct sched_rt_entity *rt_se; - struct rq *rq; int i; tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL); @@ -8364,8 +8245,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) ktime_to_ns(def_rt_bandwidth.rt_period), 0); for_each_possible_cpu(i) { - rq = cpu_rq(i); - rt_rq = kzalloc_node(sizeof(struct rt_rq), GFP_KERNEL, cpu_to_node(i)); if (!rt_rq) @@ -8376,7 +8255,7 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) if (!rt_se) goto err_free_rq; - init_tg_rt_entry(tg, rt_rq, rt_se, i, 0, parent->rt_se[i]); + init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]); } return 1; @@ -8386,17 +8265,6 @@ err_free_rq: err: return 0; } - -static inline void register_rt_sched_group(struct task_group *tg, int cpu) -{ - list_add_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list, - &cpu_rq(cpu)->leaf_rt_rq_list); -} - -static inline void unregister_rt_sched_group(struct task_group *tg, int cpu) -{ - list_del_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list); -} #else /* !CONFIG_RT_GROUP_SCHED */ static inline void free_rt_sched_group(struct task_group *tg) { @@ -8407,14 +8275,6 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent) { return 1; } - -static inline void register_rt_sched_group(struct task_group *tg, int cpu) -{ -} - -static inline void unregister_rt_sched_group(struct task_group *tg, int cpu) -{ -} #endif /* CONFIG_RT_GROUP_SCHED */ #ifdef CONFIG_CGROUP_SCHED @@ -8422,6 +8282,7 @@ static void free_sched_group(struct task_group *tg) { free_fair_sched_group(tg); free_rt_sched_group(tg); + autogroup_free(tg); kfree(tg); } @@ -8430,7 +8291,6 @@ struct task_group *sched_create_group(struct task_group *parent) { struct task_group *tg; unsigned long flags; - int i; tg = kzalloc(sizeof(*tg), GFP_KERNEL); if (!tg) @@ -8443,10 +8303,6 @@ struct task_group *sched_create_group(struct task_group *parent) goto err; spin_lock_irqsave(&task_group_lock, flags); - for_each_possible_cpu(i) { - register_fair_sched_group(tg, i); - register_rt_sched_group(tg, i); - } list_add_rcu(&tg->list, &task_groups); WARN_ON(!parent); /* root should already exist */ @@ -8476,11 +8332,11 @@ void sched_destroy_group(struct task_group *tg) unsigned long flags; int i; - spin_lock_irqsave(&task_group_lock, flags); - for_each_possible_cpu(i) { + /* end participation in shares distribution */ + for_each_possible_cpu(i) unregister_fair_sched_group(tg, i); - unregister_rt_sched_group(tg, i); - } + + spin_lock_irqsave(&task_group_lock, flags); list_del_rcu(&tg->list); list_del_rcu(&tg->siblings); spin_unlock_irqrestore(&task_group_lock, flags); @@ -8503,7 +8359,7 @@ void sched_move_task(struct task_struct *tsk) rq = task_rq_lock(tsk, &flags); running = task_current(rq, tsk); - on_rq = tsk->se.on_rq; + on_rq = tsk->on_rq; if (on_rq) dequeue_task(rq, tsk, 0); @@ -8522,38 +8378,11 @@ void sched_move_task(struct task_struct *tsk) if (on_rq) enqueue_task(rq, tsk, 0); - task_rq_unlock(rq, &flags); + task_rq_unlock(rq, tsk, &flags); } #endif /* CONFIG_CGROUP_SCHED */ #ifdef CONFIG_FAIR_GROUP_SCHED -static void __set_se_shares(struct sched_entity *se, unsigned long shares) -{ - struct cfs_rq *cfs_rq = se->cfs_rq; - int on_rq; - - on_rq = se->on_rq; - if (on_rq) - dequeue_entity(cfs_rq, se, 0); - - se->load.weight = shares; - se->load.inv_weight = 0; - - if (on_rq) - enqueue_entity(cfs_rq, se, 0); -} - -static void set_se_shares(struct sched_entity *se, unsigned long shares) -{ - struct cfs_rq *cfs_rq = se->cfs_rq; - struct rq *rq = cfs_rq->rq; - unsigned long flags; - - raw_spin_lock_irqsave(&rq->lock, flags); - __set_se_shares(se, shares); - raw_spin_unlock_irqrestore(&rq->lock, flags); -} - static DEFINE_MUTEX(shares_mutex); int sched_group_set_shares(struct task_group *tg, unsigned long shares) @@ -8576,37 +8405,19 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares) if (tg->shares == shares) goto done; - spin_lock_irqsave(&task_group_lock, flags); - for_each_possible_cpu(i) - unregister_fair_sched_group(tg, i); - list_del_rcu(&tg->siblings); - spin_unlock_irqrestore(&task_group_lock, flags); - - /* wait for any ongoing reference to this group to finish */ - synchronize_sched(); - - /* - * Now we are free to modify the group's share on each cpu - * w/o tripping rebalance_share or load_balance_fair. - */ tg->shares = shares; for_each_possible_cpu(i) { - /* - * force a rebalance - */ - cfs_rq_set_shares(tg->cfs_rq[i], 0); - set_se_shares(tg->se[i], shares); + struct rq *rq = cpu_rq(i); + struct sched_entity *se; + + se = tg->se[i]; + /* Propagate contribution to hierarchy */ + raw_spin_lock_irqsave(&rq->lock, flags); + for_each_sched_entity(se) + update_cfs_shares(group_cfs_rq(se)); + raw_spin_unlock_irqrestore(&rq->lock, flags); } - /* - * Enable load balance activity on this group, by inserting it back on - * each cpu's rq->leaf_cfs_rq_list. - */ - spin_lock_irqsave(&task_group_lock, flags); - for_each_possible_cpu(i) - register_fair_sched_group(tg, i); - list_add_rcu(&tg->siblings, &tg->parent->children); - spin_unlock_irqrestore(&task_group_lock, flags); done: mutex_unlock(&shares_mutex); return 0; @@ -8905,7 +8716,7 @@ cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp) if (!cgrp->parent) { /* This is early initialization for the top cgroup */ - return &init_task_group.css; + return &root_task_group.css; } parent = cgroup_tg(cgrp->parent); @@ -8976,6 +8787,21 @@ cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, } } +static void +cpu_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp, + struct cgroup *old_cgrp, struct task_struct *task) +{ + /* + * cgroup_exit() is called in the copy_process() failure path. + * Ignore this case since the task hasn't ran yet, this avoids + * trying to poke a half freed task state from generic code. + */ + if (!(task->flags & PF_EXITING)) + return; + + sched_move_task(task); +} + #ifdef CONFIG_FAIR_GROUP_SCHED static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype, u64 shareval) @@ -9048,6 +8874,7 @@ struct cgroup_subsys cpu_cgroup_subsys = { .destroy = cpu_cgroup_destroy, .can_attach = cpu_cgroup_can_attach, .attach = cpu_cgroup_attach, + .exit = cpu_cgroup_exit, .populate = cpu_cgroup_populate, .subsys_id = cpu_cgroup_subsys_id, .early_init = 1, @@ -9332,72 +9159,3 @@ struct cgroup_subsys cpuacct_subsys = { }; #endif /* CONFIG_CGROUP_CPUACCT */ -#ifndef CONFIG_SMP - -void synchronize_sched_expedited(void) -{ - barrier(); -} -EXPORT_SYMBOL_GPL(synchronize_sched_expedited); - -#else /* #ifndef CONFIG_SMP */ - -static atomic_t synchronize_sched_expedited_count = ATOMIC_INIT(0); - -static int synchronize_sched_expedited_cpu_stop(void *data) -{ - /* - * There must be a full memory barrier on each affected CPU - * between the time that try_stop_cpus() is called and the - * time that it returns. - * - * In the current initial implementation of cpu_stop, the - * above condition is already met when the control reaches - * this point and the following smp_mb() is not strictly - * necessary. Do smp_mb() anyway for documentation and - * robustness against future implementation changes. - */ - smp_mb(); /* See above comment block. */ - return 0; -} - -/* - * Wait for an rcu-sched grace period to elapse, but use "big hammer" - * approach to force grace period to end quickly. This consumes - * significant time on all CPUs, and is thus not recommended for - * any sort of common-case code. - * - * Note that it is illegal to call this function while holding any - * lock that is acquired by a CPU-hotplug notifier. Failing to - * observe this restriction will result in deadlock. - */ -void synchronize_sched_expedited(void) -{ - int snap, trycount = 0; - - smp_mb(); /* ensure prior mod happens before capturing snap. */ - snap = atomic_read(&synchronize_sched_expedited_count) + 1; - get_online_cpus(); - while (try_stop_cpus(cpu_online_mask, - synchronize_sched_expedited_cpu_stop, - NULL) == -EAGAIN) { - put_online_cpus(); - if (trycount++ < 10) - udelay(trycount * num_online_cpus()); - else { - synchronize_sched(); - return; - } - if (atomic_read(&synchronize_sched_expedited_count) - snap > 0) { - smp_mb(); /* ensure test happens before caller kfree */ - return; - } - get_online_cpus(); - } - atomic_inc(&synchronize_sched_expedited_count); - smp_mb__after_atomic_inc(); /* ensure post-GP actions seen after GP. */ - put_online_cpus(); -} -EXPORT_SYMBOL_GPL(synchronize_sched_expedited); - -#endif /* #else #ifndef CONFIG_SMP */ diff --git a/kernel/sched_autogroup.c b/kernel/sched_autogroup.c new file mode 100644 index 00000000000..429242f3c48 --- /dev/null +++ b/kernel/sched_autogroup.c @@ -0,0 +1,275 @@ +#ifdef CONFIG_SCHED_AUTOGROUP + +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/kallsyms.h> +#include <linux/utsname.h> + +unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1; +static struct autogroup autogroup_default; +static atomic_t autogroup_seq_nr; + +static void __init autogroup_init(struct task_struct *init_task) +{ + autogroup_default.tg = &root_task_group; + kref_init(&autogroup_default.kref); + init_rwsem(&autogroup_default.lock); + init_task->signal->autogroup = &autogroup_default; +} + +static inline void autogroup_free(struct task_group *tg) +{ + kfree(tg->autogroup); +} + +static inline void autogroup_destroy(struct kref *kref) +{ + struct autogroup *ag = container_of(kref, struct autogroup, kref); + +#ifdef CONFIG_RT_GROUP_SCHED + /* We've redirected RT tasks to the root task group... */ + ag->tg->rt_se = NULL; + ag->tg->rt_rq = NULL; +#endif + sched_destroy_group(ag->tg); +} + +static inline void autogroup_kref_put(struct autogroup *ag) +{ + kref_put(&ag->kref, autogroup_destroy); +} + +static inline struct autogroup *autogroup_kref_get(struct autogroup *ag) +{ + kref_get(&ag->kref); + return ag; +} + +static inline struct autogroup *autogroup_task_get(struct task_struct *p) +{ + struct autogroup *ag; + unsigned long flags; + + if (!lock_task_sighand(p, &flags)) + return autogroup_kref_get(&autogroup_default); + + ag = autogroup_kref_get(p->signal->autogroup); + unlock_task_sighand(p, &flags); + + return ag; +} + +#ifdef CONFIG_RT_GROUP_SCHED +static void free_rt_sched_group(struct task_group *tg); +#endif + +static inline struct autogroup *autogroup_create(void) +{ + struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL); + struct task_group *tg; + + if (!ag) + goto out_fail; + + tg = sched_create_group(&root_task_group); + + if (IS_ERR(tg)) + goto out_free; + + kref_init(&ag->kref); + init_rwsem(&ag->lock); + ag->id = atomic_inc_return(&autogroup_seq_nr); + ag->tg = tg; +#ifdef CONFIG_RT_GROUP_SCHED + /* + * Autogroup RT tasks are redirected to the root task group + * so we don't have to move tasks around upon policy change, + * or flail around trying to allocate bandwidth on the fly. + * A bandwidth exception in __sched_setscheduler() allows + * the policy change to proceed. Thereafter, task_group() + * returns &root_task_group, so zero bandwidth is required. + */ + free_rt_sched_group(tg); + tg->rt_se = root_task_group.rt_se; + tg->rt_rq = root_task_group.rt_rq; +#endif + tg->autogroup = ag; + + return ag; + +out_free: + kfree(ag); +out_fail: + if (printk_ratelimit()) { + printk(KERN_WARNING "autogroup_create: %s failure.\n", + ag ? "sched_create_group()" : "kmalloc()"); + } + + return autogroup_kref_get(&autogroup_default); +} + +static inline bool +task_wants_autogroup(struct task_struct *p, struct task_group *tg) +{ + if (tg != &root_task_group) + return false; + + if (p->sched_class != &fair_sched_class) + return false; + + /* + * We can only assume the task group can't go away on us if + * autogroup_move_group() can see us on ->thread_group list. + */ + if (p->flags & PF_EXITING) + return false; + + return true; +} + +static inline bool task_group_is_autogroup(struct task_group *tg) +{ + return !!tg->autogroup; +} + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg) +{ + int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled); + + if (enabled && task_wants_autogroup(p, tg)) + return p->signal->autogroup->tg; + + return tg; +} + +static void +autogroup_move_group(struct task_struct *p, struct autogroup *ag) +{ + struct autogroup *prev; + struct task_struct *t; + unsigned long flags; + + BUG_ON(!lock_task_sighand(p, &flags)); + + prev = p->signal->autogroup; + if (prev == ag) { + unlock_task_sighand(p, &flags); + return; + } + + p->signal->autogroup = autogroup_kref_get(ag); + + if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled)) + goto out; + + t = p; + do { + sched_move_task(t); + } while_each_thread(p, t); + +out: + unlock_task_sighand(p, &flags); + autogroup_kref_put(prev); +} + +/* Allocates GFP_KERNEL, cannot be called under any spinlock */ +void sched_autogroup_create_attach(struct task_struct *p) +{ + struct autogroup *ag = autogroup_create(); + + autogroup_move_group(p, ag); + /* drop extra reference added by autogroup_create() */ + autogroup_kref_put(ag); +} +EXPORT_SYMBOL(sched_autogroup_create_attach); + +/* Cannot be called under siglock. Currently has no users */ +void sched_autogroup_detach(struct task_struct *p) +{ + autogroup_move_group(p, &autogroup_default); +} +EXPORT_SYMBOL(sched_autogroup_detach); + +void sched_autogroup_fork(struct signal_struct *sig) +{ + sig->autogroup = autogroup_task_get(current); +} + +void sched_autogroup_exit(struct signal_struct *sig) +{ + autogroup_kref_put(sig->autogroup); +} + +static int __init setup_autogroup(char *str) +{ + sysctl_sched_autogroup_enabled = 0; + + return 1; +} + +__setup("noautogroup", setup_autogroup); + +#ifdef CONFIG_PROC_FS + +int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice) +{ + static unsigned long next = INITIAL_JIFFIES; + struct autogroup *ag; + int err; + + if (*nice < -20 || *nice > 19) + return -EINVAL; + + err = security_task_setnice(current, *nice); + if (err) + return err; + + if (*nice < 0 && !can_nice(current, *nice)) + return -EPERM; + + /* this is a heavy operation taking global locks.. */ + if (!capable(CAP_SYS_ADMIN) && time_before(jiffies, next)) + return -EAGAIN; + + next = HZ / 10 + jiffies; + ag = autogroup_task_get(p); + + down_write(&ag->lock); + err = sched_group_set_shares(ag->tg, prio_to_weight[*nice + 20]); + if (!err) + ag->nice = *nice; + up_write(&ag->lock); + + autogroup_kref_put(ag); + + return err; +} + +void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m) +{ + struct autogroup *ag = autogroup_task_get(p); + + if (!task_group_is_autogroup(ag->tg)) + goto out; + + down_read(&ag->lock); + seq_printf(m, "/autogroup-%ld nice %d\n", ag->id, ag->nice); + up_read(&ag->lock); + +out: + autogroup_kref_put(ag); +} +#endif /* CONFIG_PROC_FS */ + +#ifdef CONFIG_SCHED_DEBUG +static inline int autogroup_path(struct task_group *tg, char *buf, int buflen) +{ + if (!task_group_is_autogroup(tg)) + return 0; + + return snprintf(buf, buflen, "%s-%ld", "/autogroup", tg->autogroup->id); +} +#endif /* CONFIG_SCHED_DEBUG */ + +#endif /* CONFIG_SCHED_AUTOGROUP */ diff --git a/kernel/sched_autogroup.h b/kernel/sched_autogroup.h new file mode 100644 index 00000000000..05577055cfc --- /dev/null +++ b/kernel/sched_autogroup.h @@ -0,0 +1,41 @@ +#ifdef CONFIG_SCHED_AUTOGROUP + +struct autogroup { + /* + * reference doesn't mean how many thread attach to this + * autogroup now. It just stands for the number of task + * could use this autogroup. + */ + struct kref kref; + struct task_group *tg; + struct rw_semaphore lock; + unsigned long id; + int nice; +}; + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg); + +#else /* !CONFIG_SCHED_AUTOGROUP */ + +static inline void autogroup_init(struct task_struct *init_task) { } +static inline void autogroup_free(struct task_group *tg) { } +static inline bool task_group_is_autogroup(struct task_group *tg) +{ + return 0; +} + +static inline struct task_group * +autogroup_task_group(struct task_struct *p, struct task_group *tg) +{ + return tg; +} + +#ifdef CONFIG_SCHED_DEBUG +static inline int autogroup_path(struct task_group *tg, char *buf, int buflen) +{ + return 0; +} +#endif + +#endif /* CONFIG_SCHED_AUTOGROUP */ diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c index 52f1a149bfb..9d8af0b3fb6 100644 --- a/kernel/sched_clock.c +++ b/kernel/sched_clock.c @@ -79,7 +79,7 @@ unsigned long long __attribute__((weak)) sched_clock(void) } EXPORT_SYMBOL_GPL(sched_clock); -static __read_mostly int sched_clock_running; +__read_mostly int sched_clock_running; #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK __read_mostly int sched_clock_stable; diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index 2e1b0d17dd9..a6710a112b4 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -16,6 +16,8 @@ #include <linux/kallsyms.h> #include <linux/utsname.h> +static DEFINE_SPINLOCK(sched_debug_lock); + /* * This allows printing both to /proc/sched_debug and * to the console @@ -54,8 +56,7 @@ static unsigned long nsec_low(unsigned long long nsec) #define SPLIT_NS(x) nsec_high(x), nsec_low(x) #ifdef CONFIG_FAIR_GROUP_SCHED -static void print_cfs_group_stats(struct seq_file *m, int cpu, - struct task_group *tg) +static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg) { struct sched_entity *se = tg->se[cpu]; if (!se) @@ -87,6 +88,26 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, } #endif +#ifdef CONFIG_CGROUP_SCHED +static char group_path[PATH_MAX]; + +static char *task_group_path(struct task_group *tg) +{ + if (autogroup_path(tg, group_path, PATH_MAX)) + return group_path; + + /* + * May be NULL if the underlying cgroup isn't fully-created yet + */ + if (!tg->css.cgroup) { + group_path[0] = '\0'; + return group_path; + } + cgroup_path(tg->css.cgroup, group_path, PATH_MAX); + return group_path; +} +#endif + static void print_task(struct seq_file *m, struct rq *rq, struct task_struct *p) { @@ -109,17 +130,10 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p) SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld", 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L); #endif - #ifdef CONFIG_CGROUP_SCHED - { - char path[64]; - - rcu_read_lock(); - cgroup_path(task_group(p)->css.cgroup, path, sizeof(path)); - rcu_read_unlock(); - SEQ_printf(m, " %s", path); - } + SEQ_printf(m, " %s", task_group_path(task_group(p))); #endif + SEQ_printf(m, "\n"); } @@ -138,7 +152,7 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu) read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, p) { - if (!p->se.on_rq || task_cpu(p) != rq_cpu) + if (!p->on_rq || task_cpu(p) != rq_cpu) continue; print_task(m, rq, p); @@ -147,19 +161,6 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu) read_unlock_irqrestore(&tasklist_lock, flags); } -#if defined(CONFIG_CGROUP_SCHED) && \ - (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)) -static void task_group_path(struct task_group *tg, char *buf, int buflen) -{ - /* may be NULL if the underlying cgroup isn't fully-created yet */ - if (!tg->css.cgroup) { - buf[0] = '\0'; - return; - } - cgroup_path(tg->css.cgroup, buf, buflen); -} -#endif - void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) { s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1, @@ -168,13 +169,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) struct sched_entity *last; unsigned long flags; -#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED) - char path[128]; - struct task_group *tg = cfs_rq->tg; - - task_group_path(tg, path, sizeof(path)); - - SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path); +#ifdef CONFIG_FAIR_GROUP_SCHED + SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, task_group_path(cfs_rq->tg)); #else SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu); #endif @@ -183,7 +179,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) raw_spin_lock_irqsave(&rq->lock, flags); if (cfs_rq->rb_leftmost) - MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime; + MIN_vruntime = (__pick_first_entity(cfs_rq))->vruntime; last = __pick_last_entity(cfs_rq); if (last) max_vruntime = last->vruntime; @@ -202,33 +198,34 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) spread0 = min_vruntime - rq0_min_vruntime; SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread0", SPLIT_NS(spread0)); - SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running); - SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight); - SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over", cfs_rq->nr_spread_over); + SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running); + SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight); #ifdef CONFIG_FAIR_GROUP_SCHED #ifdef CONFIG_SMP - SEQ_printf(m, " .%-30s: %lu\n", "shares", cfs_rq->shares); + SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_avg", + SPLIT_NS(cfs_rq->load_avg)); + SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_period", + SPLIT_NS(cfs_rq->load_period)); + SEQ_printf(m, " .%-30s: %ld\n", "load_contrib", + cfs_rq->load_contribution); + SEQ_printf(m, " .%-30s: %d\n", "load_tg", + atomic_read(&cfs_rq->tg->load_weight)); #endif + print_cfs_group_stats(m, cpu, cfs_rq->tg); #endif } void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq) { -#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED) - char path[128]; - struct task_group *tg = rt_rq->tg; - - task_group_path(tg, path, sizeof(path)); - - SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path); +#ifdef CONFIG_RT_GROUP_SCHED + SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, task_group_path(rt_rq->tg)); #else SEQ_printf(m, "\nrt_rq[%d]:\n", cpu); #endif - #define P(x) \ SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x)) #define PN(x) \ @@ -243,9 +240,12 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq) #undef P } +extern __read_mostly int sched_clock_running; + static void print_cpu(struct seq_file *m, int cpu) { struct rq *rq = cpu_rq(cpu); + unsigned long flags; #ifdef CONFIG_X86 { @@ -296,14 +296,17 @@ static void print_cpu(struct seq_file *m, int cpu) P(ttwu_count); P(ttwu_local); - P(bkl_count); - #undef P +#undef P64 #endif + spin_lock_irqsave(&sched_debug_lock, flags); print_cfs_stats(m, cpu); print_rt_stats(m, cpu); + rcu_read_lock(); print_rq(m, rq, cpu); + rcu_read_unlock(); + spin_unlock_irqrestore(&sched_debug_lock, flags); } static const char *sched_tunable_scaling_names[] = { @@ -314,21 +317,42 @@ static const char *sched_tunable_scaling_names[] = { static int sched_debug_show(struct seq_file *m, void *v) { - u64 now = ktime_to_ns(ktime_get()); + u64 ktime, sched_clk, cpu_clk; + unsigned long flags; int cpu; - SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n", + local_irq_save(flags); + ktime = ktime_to_ns(ktime_get()); + sched_clk = sched_clock(); + cpu_clk = local_clock(); + local_irq_restore(flags); + + SEQ_printf(m, "Sched Debug Version: v0.10, %s %.*s\n", init_utsname()->release, (int)strcspn(init_utsname()->version, " "), init_utsname()->version); - SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now)); +#define P(x) \ + SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x)) +#define PN(x) \ + SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x)) + PN(ktime); + PN(sched_clk); + PN(cpu_clk); + P(jiffies); +#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK + P(sched_clock_stable); +#endif +#undef PN +#undef P + + SEQ_printf(m, "\n"); + SEQ_printf(m, "sysctl_sched\n"); #define P(x) \ SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x)) #define PN(x) \ SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x)) - P(jiffies); PN(sysctl_sched_latency); PN(sysctl_sched_min_granularity); PN(sysctl_sched_wakeup_granularity); @@ -414,7 +438,6 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m) P(se.statistics.wait_count); PN(se.statistics.iowait_sum); P(se.statistics.iowait_count); - P(sched_info.bkl_count); P(se.nr_migrations); P(se.statistics.nr_migrations_cold); P(se.statistics.nr_failed_migrations_affine); diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index f4f6a8326dd..37f22626225 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -22,6 +22,7 @@ #include <linux/latencytop.h> #include <linux/sched.h> +#include <linux/cpumask.h> /* * Targeted preemption latency for CPU-bound tasks: @@ -69,14 +70,6 @@ static unsigned int sched_nr_latency = 8; unsigned int sysctl_sched_child_runs_first __read_mostly; /* - * sys_sched_yield() compat mode - * - * This option switches the agressive yield implementation of the - * old scheduler back on. - */ -unsigned int __read_mostly sysctl_sched_compat_yield; - -/* * SCHED_OTHER wake-up granularity. * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds) * @@ -89,6 +82,13 @@ unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL; const_debug unsigned int sysctl_sched_migration_cost = 500000UL; +/* + * The exponential sliding window over which load is averaged for shares + * distribution. + * (default: 10msec) + */ +unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL; + static const struct sched_class fair_sched_class; /************************************************************** @@ -143,6 +143,36 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) return cfs_rq->tg->cfs_rq[this_cpu]; } +static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq) +{ + if (!cfs_rq->on_list) { + /* + * Ensure we either appear before our parent (if already + * enqueued) or force our parent to appear after us when it is + * enqueued. The fact that we always enqueue bottom-up + * reduces this to two cases. + */ + if (cfs_rq->tg->parent && + cfs_rq->tg->parent->cfs_rq[cpu_of(rq_of(cfs_rq))]->on_list) { + list_add_rcu(&cfs_rq->leaf_cfs_rq_list, + &rq_of(cfs_rq)->leaf_cfs_rq_list); + } else { + list_add_tail_rcu(&cfs_rq->leaf_cfs_rq_list, + &rq_of(cfs_rq)->leaf_cfs_rq_list); + } + + cfs_rq->on_list = 1; + } +} + +static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq) +{ + if (cfs_rq->on_list) { + list_del_rcu(&cfs_rq->leaf_cfs_rq_list); + cfs_rq->on_list = 0; + } +} + /* Iterate thr' all leaf cfs_rq's on a runqueue */ #define for_each_leaf_cfs_rq(rq, cfs_rq) \ list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) @@ -246,6 +276,14 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) return &cpu_rq(this_cpu)->cfs; } +static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq) +{ +} + +static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq) +{ +} + #define for_each_leaf_cfs_rq(rq, cfs_rq) \ for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL) @@ -320,6 +358,10 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq) } cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime); +#ifndef CONFIG_64BIT + smp_wmb(); + cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime; +#endif } /* @@ -374,7 +416,7 @@ static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) rb_erase(&se->run_node, &cfs_rq->tasks_timeline); } -static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq) +static struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq) { struct rb_node *left = cfs_rq->rb_leftmost; @@ -384,6 +426,17 @@ static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq) return rb_entry(left, struct sched_entity, run_node); } +static struct sched_entity *__pick_next_entity(struct sched_entity *se) +{ + struct rb_node *next = rb_next(&se->run_node); + + if (!next) + return NULL; + + return rb_entry(next, struct sched_entity, run_node); +} + +#ifdef CONFIG_SCHED_DEBUG static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) { struct rb_node *last = rb_last(&cfs_rq->tasks_timeline); @@ -398,7 +451,6 @@ static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) * Scheduling class statistics methods: */ -#ifdef CONFIG_SCHED_DEBUG int sched_proc_update_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) @@ -417,7 +469,6 @@ int sched_proc_update_handler(struct ctl_table *table, int write, WRT_SYSCTL(sched_min_granularity); WRT_SYSCTL(sched_latency); WRT_SYSCTL(sched_wakeup_granularity); - WRT_SYSCTL(sched_shares_ratelimit); #undef WRT_SYSCTL return 0; @@ -495,6 +546,9 @@ static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se) return calc_delta_fair(sched_slice(cfs_rq, se), se); } +static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update); +static void update_cfs_shares(struct cfs_rq *cfs_rq); + /* * Update the current task's runtime statistics. Skip current tasks that * are not in our scheduling class. @@ -514,6 +568,10 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr, curr->vruntime += delta_exec_weighted; update_min_vruntime(cfs_rq); + +#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED + cfs_rq->load_unacc_exec_time += delta_exec; +#endif } static void update_curr(struct cfs_rq *cfs_rq) @@ -633,7 +691,6 @@ account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se) list_add(&se->group_node, &cfs_rq->tasks); } cfs_rq->nr_running++; - se->on_rq = 1; } static void @@ -647,9 +704,164 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) list_del_init(&se->group_node); } cfs_rq->nr_running--; - se->on_rq = 0; } +#ifdef CONFIG_FAIR_GROUP_SCHED +# ifdef CONFIG_SMP +static void update_cfs_rq_load_contribution(struct cfs_rq *cfs_rq, + int global_update) +{ + struct task_group *tg = cfs_rq->tg; + long load_avg; + + load_avg = div64_u64(cfs_rq->load_avg, cfs_rq->load_period+1); + load_avg -= cfs_rq->load_contribution; + + if (global_update || abs(load_avg) > cfs_rq->load_contribution / 8) { + atomic_add(load_avg, &tg->load_weight); + cfs_rq->load_contribution += load_avg; + } +} + +static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) +{ + u64 period = sysctl_sched_shares_window; + u64 now, delta; + unsigned long load = cfs_rq->load.weight; + + if (cfs_rq->tg == &root_task_group) + return; + + now = rq_of(cfs_rq)->clock_task; + delta = now - cfs_rq->load_stamp; + + /* truncate load history at 4 idle periods */ + if (cfs_rq->load_stamp > cfs_rq->load_last && + now - cfs_rq->load_last > 4 * period) { + cfs_rq->load_period = 0; + cfs_rq->load_avg = 0; + delta = period - 1; + } + + cfs_rq->load_stamp = now; + cfs_rq->load_unacc_exec_time = 0; + cfs_rq->load_period += delta; + if (load) { + cfs_rq->load_last = now; + cfs_rq->load_avg += delta * load; + } + + /* consider updating load contribution on each fold or truncate */ + if (global_update || cfs_rq->load_period > period + || !cfs_rq->load_period) + update_cfs_rq_load_contribution(cfs_rq, global_update); + + while (cfs_rq->load_period > period) { + /* + * Inline assembly required to prevent the compiler + * optimising this loop into a divmod call. + * See __iter_div_u64_rem() for another example of this. + */ + asm("" : "+rm" (cfs_rq->load_period)); + cfs_rq->load_period /= 2; + cfs_rq->load_avg /= 2; + } + + if (!cfs_rq->curr && !cfs_rq->nr_running && !cfs_rq->load_avg) + list_del_leaf_cfs_rq(cfs_rq); +} + +static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) +{ + long load_weight, load, shares; + + load = cfs_rq->load.weight; + + load_weight = atomic_read(&tg->load_weight); + load_weight += load; + load_weight -= cfs_rq->load_contribution; + + shares = (tg->shares * load); + if (load_weight) + shares /= load_weight; + + if (shares < MIN_SHARES) + shares = MIN_SHARES; + if (shares > tg->shares) + shares = tg->shares; + + return shares; +} + +static void update_entity_shares_tick(struct cfs_rq *cfs_rq) +{ + if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) { + update_cfs_load(cfs_rq, 0); + update_cfs_shares(cfs_rq); + } +} +# else /* CONFIG_SMP */ +static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) +{ +} + +static inline long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) +{ + return tg->shares; +} + +static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq) +{ +} +# endif /* CONFIG_SMP */ +static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, + unsigned long weight) +{ + if (se->on_rq) { + /* commit outstanding execution time */ + if (cfs_rq->curr == se) + update_curr(cfs_rq); + account_entity_dequeue(cfs_rq, se); + } + + update_load_set(&se->load, weight); + + if (se->on_rq) + account_entity_enqueue(cfs_rq, se); +} + +static void update_cfs_shares(struct cfs_rq *cfs_rq) +{ + struct task_group *tg; + struct sched_entity *se; + long shares; + + tg = cfs_rq->tg; + se = tg->se[cpu_of(rq_of(cfs_rq))]; + if (!se) + return; +#ifndef CONFIG_SMP + if (likely(se->load.weight == tg->shares)) + return; +#endif + shares = calc_cfs_shares(cfs_rq, tg); + + reweight_entity(cfs_rq_of(se), se, shares); +} +#else /* CONFIG_FAIR_GROUP_SCHED */ +static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update) +{ +} + +static inline void update_cfs_shares(struct cfs_rq *cfs_rq) +{ +} + +static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq) +{ +} +#endif /* CONFIG_FAIR_GROUP_SCHED */ + static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) { #ifdef CONFIG_SCHEDSTATS @@ -771,7 +983,9 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) * Update run-time statistics of the 'current'. */ update_curr(cfs_rq); + update_cfs_load(cfs_rq, 0); account_entity_enqueue(cfs_rq, se); + update_cfs_shares(cfs_rq); if (flags & ENQUEUE_WAKEUP) { place_entity(cfs_rq, se, 0); @@ -782,21 +996,55 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) check_spread(cfs_rq, se); if (se != cfs_rq->curr) __enqueue_entity(cfs_rq, se); + se->on_rq = 1; + + if (cfs_rq->nr_running == 1) + list_add_leaf_cfs_rq(cfs_rq); } -static void __clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se) +static void __clear_buddies_last(struct sched_entity *se) { - if (!se || cfs_rq->last == se) - cfs_rq->last = NULL; + for_each_sched_entity(se) { + struct cfs_rq *cfs_rq = cfs_rq_of(se); + if (cfs_rq->last == se) + cfs_rq->last = NULL; + else + break; + } +} - if (!se || cfs_rq->next == se) - cfs_rq->next = NULL; +static void __clear_buddies_next(struct sched_entity *se) +{ + for_each_sched_entity(se) { + struct cfs_rq *cfs_rq = cfs_rq_of(se); + if (cfs_rq->next == se) + cfs_rq->next = NULL; + else + break; + } +} + +static void __clear_buddies_skip(struct sched_entity *se) +{ + for_each_sched_entity(se) { + struct cfs_rq *cfs_rq = cfs_rq_of(se); + if (cfs_rq->skip == se) + cfs_rq->skip = NULL; + else + break; + } } static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se) { - for_each_sched_entity(se) - __clear_buddies(cfs_rq_of(se), se); + if (cfs_rq->last == se) + __clear_buddies_last(se); + + if (cfs_rq->next == se) + __clear_buddies_next(se); + + if (cfs_rq->skip == se) + __clear_buddies_skip(se); } static void @@ -825,8 +1073,11 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags) if (se != cfs_rq->curr) __dequeue_entity(cfs_rq, se); + se->on_rq = 0; + update_cfs_load(cfs_rq, 0); account_entity_dequeue(cfs_rq, se); update_min_vruntime(cfs_rq); + update_cfs_shares(cfs_rq); /* * Normalize the entity after updating the min_vruntime because the @@ -869,9 +1120,12 @@ check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) return; if (cfs_rq->nr_running > 1) { - struct sched_entity *se = __pick_next_entity(cfs_rq); + struct sched_entity *se = __pick_first_entity(cfs_rq); s64 delta = curr->vruntime - se->vruntime; + if (delta < 0) + return; + if (delta > ideal_runtime) resched_task(rq_of(cfs_rq)->curr); } @@ -910,13 +1164,27 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) static int wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se); +/* + * Pick the next process, keeping these things in mind, in this order: + * 1) keep things fair between processes/task groups + * 2) pick the "next" process, since someone really wants that to run + * 3) pick the "last" process, for cache locality + * 4) do not run the "skip" process, if something else is available + */ static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq) { - struct sched_entity *se = __pick_next_entity(cfs_rq); + struct sched_entity *se = __pick_first_entity(cfs_rq); struct sched_entity *left = se; - if (cfs_rq->next && wakeup_preempt_entity(cfs_rq->next, left) < 1) - se = cfs_rq->next; + /* + * Avoid running the skip buddy, if running something else can + * be done without getting too unfair. + */ + if (cfs_rq->skip == se) { + struct sched_entity *second = __pick_next_entity(se); + if (second && wakeup_preempt_entity(second, left) < 1) + se = second; + } /* * Prefer last buddy, try to return the CPU to a preempted task. @@ -924,6 +1192,12 @@ static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq) if (cfs_rq->last && wakeup_preempt_entity(cfs_rq->last, left) < 1) se = cfs_rq->last; + /* + * Someone really wants this to run. If it's not unfair, run it. + */ + if (cfs_rq->next && wakeup_preempt_entity(cfs_rq->next, left) < 1) + se = cfs_rq->next; + clear_buddies(cfs_rq, se); return se; @@ -955,6 +1229,11 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued) */ update_curr(cfs_rq); + /* + * Update share accounting for long-running entities. + */ + update_entity_shares_tick(cfs_rq); + #ifdef CONFIG_SCHED_HRTICK /* * queued ticks are scheduled to match the slice, so don't bother @@ -1055,9 +1334,18 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags) flags = ENQUEUE_WAKEUP; } + for_each_sched_entity(se) { + struct cfs_rq *cfs_rq = cfs_rq_of(se); + + update_cfs_load(cfs_rq, 0); + update_cfs_shares(cfs_rq); + } + hrtick_update(rq); } +static void set_next_buddy(struct sched_entity *se); + /* * The dequeue_task method is called before nr_running is * decreased. We remove the task from the rbtree and @@ -1067,73 +1355,56 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags) { struct cfs_rq *cfs_rq; struct sched_entity *se = &p->se; + int task_sleep = flags & DEQUEUE_SLEEP; for_each_sched_entity(se) { cfs_rq = cfs_rq_of(se); dequeue_entity(cfs_rq, se, flags); + /* Don't dequeue parent if it has other entities besides us */ - if (cfs_rq->load.weight) + if (cfs_rq->load.weight) { + /* + * Bias pick_next to pick a task from this cfs_rq, as + * p is sleeping when it is within its sched_slice. + */ + if (task_sleep && parent_entity(se)) + set_next_buddy(parent_entity(se)); break; + } flags |= DEQUEUE_SLEEP; } - hrtick_update(rq); -} - -/* - * sched_yield() support is very simple - we dequeue and enqueue. - * - * If compat_yield is turned on then we requeue to the end of the tree. - */ -static void yield_task_fair(struct rq *rq) -{ - struct task_struct *curr = rq->curr; - struct cfs_rq *cfs_rq = task_cfs_rq(curr); - struct sched_entity *rightmost, *se = &curr->se; - - /* - * Are we the only task in the tree? - */ - if (unlikely(cfs_rq->nr_running == 1)) - return; - - clear_buddies(cfs_rq, se); - - if (likely(!sysctl_sched_compat_yield) && curr->policy != SCHED_BATCH) { - update_rq_clock(rq); - /* - * Update run-time statistics of the 'current'. - */ - update_curr(cfs_rq); + for_each_sched_entity(se) { + struct cfs_rq *cfs_rq = cfs_rq_of(se); - return; + update_cfs_load(cfs_rq, 0); + update_cfs_shares(cfs_rq); } - /* - * Find the rightmost entry in the rbtree: - */ - rightmost = __pick_last_entity(cfs_rq); - /* - * Already in the rightmost position? - */ - if (unlikely(!rightmost || entity_before(rightmost, se))) - return; - /* - * Minimally necessary key value to be last in the tree: - * Upon rescheduling, sched_class::put_prev_task() will place - * 'current' within the tree based on its new key value. - */ - se->vruntime = rightmost->vruntime + 1; + hrtick_update(rq); } #ifdef CONFIG_SMP -static void task_waking_fair(struct rq *rq, struct task_struct *p) +static void task_waking_fair(struct task_struct *p) { struct sched_entity *se = &p->se; struct cfs_rq *cfs_rq = cfs_rq_of(se); + u64 min_vruntime; - se->vruntime -= cfs_rq->min_vruntime; +#ifndef CONFIG_64BIT + u64 min_vruntime_copy; + + do { + min_vruntime_copy = cfs_rq->min_vruntime_copy; + smp_rmb(); + min_vruntime = cfs_rq->min_vruntime; + } while (min_vruntime != min_vruntime_copy); +#else + min_vruntime = cfs_rq->min_vruntime; +#endif + + se->vruntime -= min_vruntime; } #ifdef CONFIG_FAIR_GROUP_SCHED @@ -1143,67 +1414,36 @@ static void task_waking_fair(struct rq *rq, struct task_struct *p) * Adding load to a group doesn't make a group heavier, but can cause movement * of group shares between cpus. Assuming the shares were perfectly aligned one * can calculate the shift in shares. - * - * The problem is that perfectly aligning the shares is rather expensive, hence - * we try to avoid doing that too often - see update_shares(), which ratelimits - * this change. - * - * We compensate this by not only taking the current delta into account, but - * also considering the delta between when the shares were last adjusted and - * now. - * - * We still saw a performance dip, some tracing learned us that between - * cgroup:/ and cgroup:/foo balancing the number of affine wakeups increased - * significantly. Therefore try to bias the error in direction of failing - * the affine wakeup. - * */ -static long effective_load(struct task_group *tg, int cpu, - long wl, long wg) +static long effective_load(struct task_group *tg, int cpu, long wl, long wg) { struct sched_entity *se = tg->se[cpu]; if (!tg->parent) return wl; - /* - * By not taking the decrease of shares on the other cpu into - * account our error leans towards reducing the affine wakeups. - */ - if (!wl && sched_feat(ASYM_EFF_LOAD)) - return wl; - for_each_sched_entity(se) { - long S, rw, s, a, b; - long more_w; - - /* - * Instead of using this increment, also add the difference - * between when the shares were last updated and now. - */ - more_w = se->my_q->load.weight - se->my_q->rq_weight; - wl += more_w; - wg += more_w; + long lw, w; - S = se->my_q->tg->shares; - s = se->my_q->shares; - rw = se->my_q->rq_weight; + tg = se->my_q->tg; + w = se->my_q->load.weight; - a = S*(rw + wl); - b = S*rw + s*wg; + /* use this cpu's instantaneous contribution */ + lw = atomic_read(&tg->load_weight); + lw -= se->my_q->load_contribution; + lw += w + wg; - wl = s*(a-b); + wl += w; - if (likely(b)) - wl /= b; + if (lw > 0 && wl < lw) + wl = (wl * tg->shares) / lw; + else + wl = tg->shares; - /* - * Assume the group is already running and will - * thus already be accounted for in the weight. - * - * That is, moving shares between CPUs, does not - * alter the group weight. - */ + /* zero point is MIN_SHARES */ + if (wl < MIN_SHARES) + wl = MIN_SHARES; + wl -= se->load.weight; wg = 0; } @@ -1222,7 +1462,7 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu, static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) { - unsigned long this_load, load; + s64 this_load, load; int idx, this_cpu, prev_cpu; unsigned long tl_per_task; struct task_group *tg; @@ -1261,8 +1501,8 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) * Otherwise check if either cpus are near enough in load to allow this * task to be woken on this_cpu. */ - if (this_load) { - unsigned long this_eff_load, prev_eff_load; + if (this_load > 0) { + s64 this_eff_load, prev_eff_load; this_eff_load = 100; this_eff_load *= power_of(prev_cpu); @@ -1409,6 +1649,7 @@ static int select_idle_sibling(struct task_struct *p, int target) /* * Otherwise, iterate the domains and find an elegible idle cpu. */ + rcu_read_lock(); for_each_domain(target, sd) { if (!(sd->flags & SD_SHARE_PKG_RESOURCES)) break; @@ -1428,6 +1669,7 @@ static int select_idle_sibling(struct task_struct *p, int target) cpumask_test_cpu(prev_cpu, sched_domain_span(sd))) break; } + rcu_read_unlock(); return target; } @@ -1444,7 +1686,7 @@ static int select_idle_sibling(struct task_struct *p, int target) * preempt must be disabled. */ static int -select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_flags) +select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags) { struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL; int cpu = smp_processor_id(); @@ -1460,6 +1702,7 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ new_cpu = prev_cpu; } + rcu_read_lock(); for_each_domain(cpu, tmp) { if (!(tmp->flags & SD_LOAD_BALANCE)) continue; @@ -1508,28 +1751,12 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ sd = tmp; } -#ifdef CONFIG_FAIR_GROUP_SCHED - if (sched_feat(LB_SHARES_UPDATE)) { - /* - * Pick the largest domain to update shares over - */ - tmp = sd; - if (affine_sd && (!tmp || affine_sd->span_weight > sd->span_weight)) - tmp = affine_sd; - - if (tmp) { - raw_spin_unlock(&rq->lock); - update_shares(tmp); - raw_spin_lock(&rq->lock); - } - } -#endif - if (affine_sd) { if (cpu == prev_cpu || wake_affine(affine_sd, p, sync)) - return select_idle_sibling(p, cpu); - else - return select_idle_sibling(p, prev_cpu); + prev_cpu = cpu; + + new_cpu = select_idle_sibling(p, prev_cpu); + goto unlock; } while (sd) { @@ -1570,6 +1797,8 @@ select_task_rq_fair(struct rq *rq, struct task_struct *p, int sd_flag, int wake_ } /* while loop will break here if sd == NULL */ } +unlock: + rcu_read_unlock(); return new_cpu; } @@ -1593,10 +1822,7 @@ wakeup_gran(struct sched_entity *curr, struct sched_entity *se) * This is especially important for buddies when the leftmost * task is higher priority than the buddy. */ - if (unlikely(se->load.weight != NICE_0_LOAD)) - gran = calc_delta_fair(gran, se); - - return gran; + return calc_delta_fair(gran, se); } /* @@ -1630,18 +1856,26 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se) static void set_last_buddy(struct sched_entity *se) { - if (likely(task_of(se)->policy != SCHED_IDLE)) { - for_each_sched_entity(se) - cfs_rq_of(se)->last = se; - } + if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE)) + return; + + for_each_sched_entity(se) + cfs_rq_of(se)->last = se; } static void set_next_buddy(struct sched_entity *se) { - if (likely(task_of(se)->policy != SCHED_IDLE)) { - for_each_sched_entity(se) - cfs_rq_of(se)->next = se; - } + if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE)) + return; + + for_each_sched_entity(se) + cfs_rq_of(se)->next = se; +} + +static void set_skip_buddy(struct sched_entity *se) +{ + for_each_sched_entity(se) + cfs_rq_of(se)->skip = se; } /* @@ -1653,18 +1887,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ struct sched_entity *se = &curr->se, *pse = &p->se; struct cfs_rq *cfs_rq = task_cfs_rq(curr); int scale = cfs_rq->nr_running >= sched_nr_latency; - - if (unlikely(rt_prio(p->prio))) - goto preempt; - - if (unlikely(p->sched_class != &fair_sched_class)) - return; + int next_buddy_marked = 0; if (unlikely(se == pse)) return; - if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) + if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) { set_next_buddy(pse); + next_buddy_marked = 1; + } /* * We can come here with TIF_NEED_RESCHED already set from new task @@ -1673,16 +1904,18 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ if (test_tsk_need_resched(curr)) return; + /* Idle tasks are by definition preempted by non-idle tasks. */ + if (unlikely(curr->policy == SCHED_IDLE) && + likely(p->policy != SCHED_IDLE)) + goto preempt; + /* - * Batch and idle tasks do not preempt (their preemption is driven by - * the tick): + * Batch and idle tasks do not preempt non-idle tasks (their preemption + * is driven by the tick): */ if (unlikely(p->policy != SCHED_NORMAL)) return; - /* Idle tasks are by definition preempted by everybody. */ - if (unlikely(curr->policy == SCHED_IDLE)) - goto preempt; if (!sched_feat(WAKEUP_PREEMPT)) return; @@ -1690,8 +1923,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ update_curr(cfs_rq); find_matching_se(&se, &pse); BUG_ON(!pse); - if (wakeup_preempt_entity(se, pse) == 1) + if (wakeup_preempt_entity(se, pse) == 1) { + /* + * Bias pick_next to pick the sched entity that is + * triggering this preemption. + */ + if (!next_buddy_marked) + set_next_buddy(pse); goto preempt; + } return; @@ -1748,6 +1988,51 @@ static void put_prev_task_fair(struct rq *rq, struct task_struct *prev) } } +/* + * sched_yield() is very simple + * + * The magic of dealing with the ->skip buddy is in pick_next_entity. + */ +static void yield_task_fair(struct rq *rq) +{ + struct task_struct *curr = rq->curr; + struct cfs_rq *cfs_rq = task_cfs_rq(curr); + struct sched_entity *se = &curr->se; + + /* + * Are we the only task in the tree? + */ + if (unlikely(rq->nr_running == 1)) + return; + + clear_buddies(cfs_rq, se); + + if (curr->policy != SCHED_BATCH) { + update_rq_clock(rq); + /* + * Update run-time statistics of the 'current'. + */ + update_curr(cfs_rq); + } + + set_skip_buddy(se); +} + +static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preempt) +{ + struct sched_entity *se = &p->se; + + if (!se->on_rq) + return false; + + /* Tell the scheduler that we'd really like pse to run next. */ + set_next_buddy(se); + + yield_task_fair(rq); + + return true; +} + #ifdef CONFIG_SMP /************************************************** * Fair scheduling class load-balancing methods: @@ -1764,10 +2049,6 @@ static void pull_task(struct rq *src_rq, struct task_struct *p, set_task_cpu(p, this_cpu); activate_task(this_rq, p, 0); check_preempt_curr(this_rq, p, 0); - - /* re-arm NEWIDLE balancing when moving tasks */ - src_rq->avg_idle = this_rq->avg_idle = 2*sysctl_sched_migration_cost; - this_rq->idle_stamp = 0; } /* @@ -1861,23 +2142,22 @@ static unsigned long balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, int *all_pinned, - int *this_best_prio, struct cfs_rq *busiest_cfs_rq) + struct cfs_rq *busiest_cfs_rq) { - int loops = 0, pulled = 0, pinned = 0; + int loops = 0, pulled = 0; long rem_load_move = max_load_move; struct task_struct *p, *n; if (max_load_move == 0) goto out; - pinned = 1; - list_for_each_entry_safe(p, n, &busiest_cfs_rq->tasks, se.group_node) { if (loops++ > sysctl_sched_nr_migrate) break; if ((p->se.load.weight >> 1) > rem_load_move || - !can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) + !can_migrate_task(p, busiest, this_cpu, sd, idle, + all_pinned)) continue; pull_task(busiest, p, this_rq, this_cpu); @@ -1900,9 +2180,6 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, */ if (rem_load_move <= 0) break; - - if (p->prio < *this_best_prio) - *this_best_prio = p->prio; } out: /* @@ -1912,18 +2189,57 @@ out: */ schedstat_add(sd, lb_gained[idle], pulled); - if (all_pinned) - *all_pinned = pinned; - return max_load_move - rem_load_move; } #ifdef CONFIG_FAIR_GROUP_SCHED +/* + * update tg->load_weight by folding this cpu's load_avg + */ +static int update_shares_cpu(struct task_group *tg, int cpu) +{ + struct cfs_rq *cfs_rq; + unsigned long flags; + struct rq *rq; + + if (!tg->se[cpu]) + return 0; + + rq = cpu_rq(cpu); + cfs_rq = tg->cfs_rq[cpu]; + + raw_spin_lock_irqsave(&rq->lock, flags); + + update_rq_clock(rq); + update_cfs_load(cfs_rq, 1); + + /* + * We need to update shares after updating tg->load_weight in + * order to adjust the weight of groups with long running tasks. + */ + update_cfs_shares(cfs_rq); + + raw_spin_unlock_irqrestore(&rq->lock, flags); + + return 0; +} + +static void update_shares(int cpu) +{ + struct cfs_rq *cfs_rq; + struct rq *rq = cpu_rq(cpu); + + rcu_read_lock(); + for_each_leaf_cfs_rq(rq, cfs_rq) + update_shares_cpu(cfs_rq->tg, cpu); + rcu_read_unlock(); +} + static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, int *this_best_prio) + int *all_pinned) { long rem_load_move = max_load_move; int busiest_cpu = cpu_of(busiest); @@ -1948,7 +2264,7 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, rem_load = div_u64(rem_load, busiest_h_load + 1); moved_load = balance_tasks(this_rq, this_cpu, busiest, - rem_load, sd, idle, all_pinned, this_best_prio, + rem_load, sd, idle, all_pinned, busiest_cfs_rq); if (!moved_load) @@ -1966,15 +2282,19 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, return max_load_move - rem_load_move; } #else +static inline void update_shares(int cpu) +{ +} + static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, int *this_best_prio) + int *all_pinned) { return balance_tasks(this_rq, this_cpu, busiest, max_load_move, sd, idle, all_pinned, - this_best_prio, &busiest->cfs); + &busiest->cfs); } #endif @@ -1991,12 +2311,11 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, int *all_pinned) { unsigned long total_load_moved = 0, load_moved; - int this_best_prio = this_rq->curr->prio; do { load_moved = load_balance_fair(this_rq, this_cpu, busiest, max_load_move - total_load_moved, - sd, idle, all_pinned, &this_best_prio); + sd, idle, all_pinned); total_load_moved += load_moved; @@ -2035,13 +2354,16 @@ struct sd_lb_stats { unsigned long this_load_per_task; unsigned long this_nr_running; unsigned long this_has_capacity; + unsigned int this_idle_cpus; /* Statistics of the busiest group */ + unsigned int busiest_idle_cpus; unsigned long max_load; unsigned long busiest_load_per_task; unsigned long busiest_nr_running; unsigned long busiest_group_capacity; unsigned long busiest_has_capacity; + unsigned int busiest_group_weight; int group_imb; /* Is there imbalance in this sd */ #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) @@ -2063,6 +2385,8 @@ struct sg_lb_stats { unsigned long sum_nr_running; /* Nr tasks running in the group */ unsigned long sum_weighted_load; /* Weighted load of group's tasks */ unsigned long group_capacity; + unsigned long idle_cpus; + unsigned long group_weight; int group_imb; /* Is there an imbalance in the group ? */ int group_has_capacity; /* Is there extra capacity in the group? */ }; @@ -2360,7 +2684,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group) /* * Only siblings can have significantly less than SCHED_LOAD_SCALE */ - if (sd->level != SD_LV_SIBLING) + if (!(sd->flags & SD_SHARE_CPUPOWER)) return 0; /* @@ -2379,7 +2703,6 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group) * @this_cpu: Cpu for which load balance is currently performed. * @idle: Idle status of this_cpu * @load_idx: Load index of sched_domain of this_cpu for load calc. - * @sd_idle: Idle status of the sched_domain containing group. * @local_group: Does group contain this_cpu. * @cpus: Set of cpus considered for load balancing. * @balance: Should we balance. @@ -2387,7 +2710,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group) */ static inline void update_sg_lb_stats(struct sched_domain *sd, struct sched_group *group, int this_cpu, - enum cpu_idle_type idle, int load_idx, int *sd_idle, + enum cpu_idle_type idle, int load_idx, int local_group, const struct cpumask *cpus, int *balance, struct sg_lb_stats *sgs) { @@ -2407,9 +2730,6 @@ static inline void update_sg_lb_stats(struct sched_domain *sd, for_each_cpu_and(i, sched_group_cpus(group), cpus) { struct rq *rq = cpu_rq(i); - if (*sd_idle && rq->nr_running) - *sd_idle = 0; - /* Bias balancing toward cpus of our domain */ if (local_group) { if (idle_cpu(i) && !first_idle_cpu) { @@ -2431,7 +2751,8 @@ static inline void update_sg_lb_stats(struct sched_domain *sd, sgs->group_load += load; sgs->sum_nr_running += rq->nr_running; sgs->sum_weighted_load += weighted_cpuload(i); - + if (idle_cpu(i)) + sgs->idle_cpus++; } /* @@ -2453,7 +2774,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd, /* * Consider the group unbalanced when the imbalance is larger - * than the average weight of two tasks. + * than the average weight of a task. * * APZ: with cgroup the avg task weight can vary wildly and * might not be a suitable number - should we keep a @@ -2463,12 +2784,13 @@ static inline void update_sg_lb_stats(struct sched_domain *sd, if (sgs->sum_nr_running) avg_load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running; - if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task && max_nr_running > 1) + if ((max_cpu_load - min_cpu_load) >= avg_load_per_task && max_nr_running > 1) sgs->group_imb = 1; sgs->group_capacity = DIV_ROUND_CLOSEST(group->cpu_power, SCHED_LOAD_SCALE); if (!sgs->group_capacity) sgs->group_capacity = fix_small_capacity(sd, group); + sgs->group_weight = group->group_weight; if (sgs->group_capacity > sgs->sum_nr_running) sgs->group_has_capacity = 1; @@ -2522,15 +2844,13 @@ static bool update_sd_pick_busiest(struct sched_domain *sd, * @sd: sched_domain whose statistics are to be updated. * @this_cpu: Cpu for which load balance is currently performed. * @idle: Idle status of this_cpu - * @sd_idle: Idle status of the sched_domain containing sg. * @cpus: Set of cpus considered for load balancing. * @balance: Should we balance. * @sds: variable to hold the statistics for this sched_domain. */ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu, - enum cpu_idle_type idle, int *sd_idle, - const struct cpumask *cpus, int *balance, - struct sd_lb_stats *sds) + enum cpu_idle_type idle, const struct cpumask *cpus, + int *balance, struct sd_lb_stats *sds) { struct sched_domain *child = sd->child; struct sched_group *sg = sd->groups; @@ -2548,7 +2868,7 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu, local_group = cpumask_test_cpu(this_cpu, sched_group_cpus(sg)); memset(&sgs, 0, sizeof(sgs)); - update_sg_lb_stats(sd, sg, this_cpu, idle, load_idx, sd_idle, + update_sg_lb_stats(sd, sg, this_cpu, idle, load_idx, local_group, cpus, balance, &sgs); if (local_group && !(*balance)) @@ -2576,13 +2896,16 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu, sds->this_nr_running = sgs.sum_nr_running; sds->this_load_per_task = sgs.sum_weighted_load; sds->this_has_capacity = sgs.group_has_capacity; + sds->this_idle_cpus = sgs.idle_cpus; } else if (update_sd_pick_busiest(sd, sds, sg, &sgs, this_cpu)) { sds->max_load = sgs.avg_load; sds->busiest = sg; sds->busiest_nr_running = sgs.sum_nr_running; + sds->busiest_idle_cpus = sgs.idle_cpus; sds->busiest_group_capacity = sgs.group_capacity; sds->busiest_load_per_task = sgs.sum_weighted_load; sds->busiest_has_capacity = sgs.group_has_capacity; + sds->busiest_group_weight = sgs.group_weight; sds->group_imb = sgs.group_imb; } @@ -2771,7 +3094,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu, /* * if *imbalance is less than the average load per runnable task - * there is no gaurantee that any tasks will be moved so we'll have + * there is no guarantee that any tasks will be moved so we'll have * a think about bumping its value to force at least one task to be * moved */ @@ -2797,7 +3120,6 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu, * @imbalance: Variable which stores amount of weighted load which should * be moved to restore balance/put a group to idle. * @idle: The idle status of this_cpu. - * @sd_idle: The idleness of sd * @cpus: The set of CPUs under consideration for load-balancing. * @balance: Pointer to a variable indicating if this_cpu * is the appropriate cpu to perform load balancing at this_level. @@ -2810,7 +3132,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu, static struct sched_group * find_busiest_group(struct sched_domain *sd, int this_cpu, unsigned long *imbalance, enum cpu_idle_type idle, - int *sd_idle, const struct cpumask *cpus, int *balance) + const struct cpumask *cpus, int *balance) { struct sd_lb_stats sds; @@ -2820,22 +3142,11 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, * Compute the various statistics relavent for load balancing at * this level. */ - update_sd_lb_stats(sd, this_cpu, idle, sd_idle, cpus, - balance, &sds); - - /* Cases where imbalance does not exist from POV of this_cpu */ - /* 1) this_cpu is not the appropriate cpu to perform load balancing - * at this level. - * 2) There is no busy sibling group to pull from. - * 3) This group is the busiest group. - * 4) This group is more busy than the avg busieness at this - * sched_domain. - * 5) The imbalance is within the specified limit. - * - * Note: when doing newidle balance, if the local group has excess - * capacity (i.e. nr_running < group_capacity) and the busiest group - * does not have any capacity, we force a load balance to pull tasks - * to the local group. In this case, we skip past checks 3, 4 and 5. + update_sd_lb_stats(sd, this_cpu, idle, cpus, balance, &sds); + + /* + * this_cpu is not the appropriate cpu to perform load balancing at + * this level. */ if (!(*balance)) goto ret; @@ -2844,24 +3155,57 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, check_asym_packing(sd, &sds, this_cpu, imbalance)) return sds.busiest; + /* There is no busy sibling group to pull tasks from */ if (!sds.busiest || sds.busiest_nr_running == 0) goto out_balanced; - /* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */ + sds.avg_load = (SCHED_LOAD_SCALE * sds.total_load) / sds.total_pwr; + + /* + * If the busiest group is imbalanced the below checks don't + * work because they assumes all things are equal, which typically + * isn't true due to cpus_allowed constraints and the like. + */ + if (sds.group_imb) + goto force_balance; + + /* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */ if (idle == CPU_NEWLY_IDLE && sds.this_has_capacity && !sds.busiest_has_capacity) goto force_balance; + /* + * If the local group is more busy than the selected busiest group + * don't try and pull any tasks. + */ if (sds.this_load >= sds.max_load) goto out_balanced; - sds.avg_load = (SCHED_LOAD_SCALE * sds.total_load) / sds.total_pwr; - + /* + * Don't pull any tasks if this group is already above the domain + * average load. + */ if (sds.this_load >= sds.avg_load) goto out_balanced; - if (100 * sds.max_load <= sd->imbalance_pct * sds.this_load) - goto out_balanced; + if (idle == CPU_IDLE) { + /* + * This cpu is idle. If the busiest group load doesn't + * have more tasks than the number of available cpu's and + * there is no imbalance between this and busiest group + * wrt to idle cpu's, it is balanced. + */ + if ((sds.this_idle_cpus <= sds.busiest_idle_cpus + 1) && + sds.busiest_nr_running <= sds.busiest_group_weight) + goto out_balanced; + } else { + /* + * In the CPU_NEWLY_IDLE, CPU_NOT_IDLE cases, use + * imbalance_pct to be conservative. + */ + if (100 * sds.max_load <= sd->imbalance_pct * sds.this_load) + goto out_balanced; + } force_balance: /* Looks like there is an imbalance. Compute it */ @@ -2939,7 +3283,7 @@ find_busiest_queue(struct sched_domain *sd, struct sched_group *group, /* Working cpumask for load_balance and load_balance_newidle. */ static DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask); -static int need_active_balance(struct sched_domain *sd, int sd_idle, int idle, +static int need_active_balance(struct sched_domain *sd, int idle, int busiest_cpu, int this_cpu) { if (idle == CPU_NEWLY_IDLE) { @@ -2971,10 +3315,6 @@ static int need_active_balance(struct sched_domain *sd, int sd_idle, int idle, * move_tasks() will succeed. ld_moved will be true and this * active balance code will not be triggered. */ - if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && - !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) - return 0; - if (sched_mc_power_savings < POWERSAVINGS_BALANCE_WAKEUP) return 0; } @@ -2992,7 +3332,7 @@ static int load_balance(int this_cpu, struct rq *this_rq, struct sched_domain *sd, enum cpu_idle_type idle, int *balance) { - int ld_moved, all_pinned = 0, active_balance = 0, sd_idle = 0; + int ld_moved, all_pinned = 0, active_balance = 0; struct sched_group *group; unsigned long imbalance; struct rq *busiest; @@ -3001,21 +3341,10 @@ static int load_balance(int this_cpu, struct rq *this_rq, cpumask_copy(cpus, cpu_active_mask); - /* - * When power savings policy is enabled for the parent domain, idle - * sibling can pick up load irrespective of busy siblings. In this case, - * let the state of idle sibling percolate up as CPU_IDLE, instead of - * portraying it as CPU_NOT_IDLE. - */ - if (idle != CPU_NOT_IDLE && sd->flags & SD_SHARE_CPUPOWER && - !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) - sd_idle = 1; - schedstat_inc(sd, lb_count[idle]); redo: - update_shares(sd); - group = find_busiest_group(sd, this_cpu, &imbalance, idle, &sd_idle, + group = find_busiest_group(sd, this_cpu, &imbalance, idle, cpus, balance); if (*balance == 0) @@ -3044,6 +3373,7 @@ redo: * still unbalanced. ld_moved simply stays zero, so it is * correctly treated as an imbalance. */ + all_pinned = 1; local_irq_save(flags); double_rq_lock(this_rq, busiest); ld_moved = move_tasks(this_rq, this_cpu, busiest, @@ -3077,8 +3407,7 @@ redo: if (idle != CPU_NEWLY_IDLE) sd->nr_balance_failed++; - if (need_active_balance(sd, sd_idle, idle, cpu_of(busiest), - this_cpu)) { + if (need_active_balance(sd, idle, cpu_of(busiest), this_cpu)) { raw_spin_lock_irqsave(&busiest->lock, flags); /* don't kick the active_load_balance_cpu_stop, @@ -3133,10 +3462,6 @@ redo: sd->balance_interval *= 2; } - if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER && - !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) - ld_moved = -1; - goto out; out_balanced: @@ -3150,14 +3475,8 @@ out_one_pinned: (sd->balance_interval < sd->max_interval)) sd->balance_interval *= 2; - if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && - !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) - ld_moved = -1; - else - ld_moved = 0; + ld_moved = 0; out: - if (ld_moved) - update_shares(sd); return ld_moved; } @@ -3181,6 +3500,8 @@ static void idle_balance(int this_cpu, struct rq *this_rq) */ raw_spin_unlock(&this_rq->lock); + update_shares(this_cpu); + rcu_read_lock(); for_each_domain(this_cpu, sd) { unsigned long interval; int balance = 1; @@ -3197,9 +3518,12 @@ static void idle_balance(int this_cpu, struct rq *this_rq) interval = msecs_to_jiffies(sd->balance_interval); if (time_after(next_balance, sd->last_balance + interval)) next_balance = sd->last_balance + interval; - if (pulled_task) + if (pulled_task) { + this_rq->idle_stamp = 0; break; + } } + rcu_read_unlock(); raw_spin_lock(&this_rq->lock); @@ -3248,6 +3572,7 @@ static int active_load_balance_cpu_stop(void *data) double_lock_balance(busiest_rq, target_rq); /* Search for an sd spanning us and the target CPU. */ + rcu_read_lock(); for_each_domain(target_cpu, sd) { if ((sd->flags & SD_LOAD_BALANCE) && cpumask_test_cpu(busiest_cpu, sched_domain_span(sd))) @@ -3263,6 +3588,7 @@ static int active_load_balance_cpu_stop(void *data) else schedstat_inc(sd, alb_failed); } + rcu_read_unlock(); double_unlock_balance(busiest_rq, target_rq); out_unlock: busiest_rq->active_balance = 0; @@ -3389,6 +3715,7 @@ static int find_new_ilb(int cpu) { struct sched_domain *sd; struct sched_group *ilb_group; + int ilb = nr_cpu_ids; /* * Have idle load balancer selection from semi-idle packages only @@ -3404,20 +3731,25 @@ static int find_new_ilb(int cpu) if (cpumask_weight(nohz.idle_cpus_mask) < 2) goto out_done; + rcu_read_lock(); for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) { ilb_group = sd->groups; do { - if (is_semi_idle_group(ilb_group)) - return cpumask_first(nohz.grp_idle_mask); + if (is_semi_idle_group(ilb_group)) { + ilb = cpumask_first(nohz.grp_idle_mask); + goto unlock; + } ilb_group = ilb_group->next; } while (ilb_group != sd->groups); } +unlock: + rcu_read_unlock(); out_done: - return nr_cpu_ids; + return ilb; } #else /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */ static inline int find_new_ilb(int call_cpu) @@ -3532,6 +3864,17 @@ void select_nohz_load_balancer(int stop_tick) static DEFINE_SPINLOCK(balancing); +static unsigned long __read_mostly max_load_balance_interval = HZ/10; + +/* + * Scale the max load_balance interval with the number of CPUs in the system. + * This trades load-balance latency on larger machines for less cross talk. + */ +static void update_max_interval(void) +{ + max_load_balance_interval = HZ*num_online_cpus()/10; +} + /* * It checks each scheduling domain to see if it is due to be balanced, * and initiates a balancing operation if so. @@ -3549,6 +3892,9 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle) int update_next_balance = 0; int need_serialize; + update_shares(cpu); + + rcu_read_lock(); for_each_domain(cpu, sd) { if (!(sd->flags & SD_LOAD_BALANCE)) continue; @@ -3559,10 +3905,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle) /* scale ms to jiffies */ interval = msecs_to_jiffies(interval); - if (unlikely(!interval)) - interval = 1; - if (interval > HZ*NR_CPUS/10) - interval = HZ*NR_CPUS/10; + interval = clamp(interval, 1UL, max_load_balance_interval); need_serialize = sd->flags & SD_SERIALIZE; @@ -3575,8 +3918,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle) if (load_balance(cpu, rq, sd, idle, &balance)) { /* * We've pulled tasks over so either we're no - * longer idle, or one of our SMT siblings is - * not idle. + * longer idle. */ idle = CPU_NOT_IDLE; } @@ -3598,6 +3940,7 @@ out: if (!balance) break; } + rcu_read_unlock(); /* * next_balance will be updated only when there is a need. @@ -3823,33 +4166,62 @@ static void task_fork_fair(struct task_struct *p) * Priority of the task has changed. Check to see if we preempt * the current task. */ -static void prio_changed_fair(struct rq *rq, struct task_struct *p, - int oldprio, int running) +static void +prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio) { + if (!p->se.on_rq) + return; + /* * Reschedule if we are currently running on this runqueue and * our priority decreased, or if we are not currently running on * this runqueue and our priority is higher than the current's */ - if (running) { + if (rq->curr == p) { if (p->prio > oldprio) resched_task(rq->curr); } else check_preempt_curr(rq, p, 0); } +static void switched_from_fair(struct rq *rq, struct task_struct *p) +{ + struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); + + /* + * Ensure the task's vruntime is normalized, so that when its + * switched back to the fair class the enqueue_entity(.flags=0) will + * do the right thing. + * + * If it was on_rq, then the dequeue_entity(.flags=0) will already + * have normalized the vruntime, if it was !on_rq, then only when + * the task is sleeping will it still have non-normalized vruntime. + */ + if (!se->on_rq && p->state != TASK_RUNNING) { + /* + * Fix up our vruntime so that the current sleep doesn't + * cause 'unlimited' sleep bonus. + */ + place_entity(cfs_rq, se, 0); + se->vruntime -= cfs_rq->min_vruntime; + } +} + /* * We switched to the sched_fair class. */ -static void switched_to_fair(struct rq *rq, struct task_struct *p, - int running) +static void switched_to_fair(struct rq *rq, struct task_struct *p) { + if (!p->se.on_rq) + return; + /* * We were most likely switched from sched_rt, so * kick off the schedule if running, otherwise just see * if we can still preempt the current task. */ - if (running) + if (rq->curr == p) resched_task(rq->curr); else check_preempt_curr(rq, p, 0); @@ -3915,6 +4287,7 @@ static const struct sched_class fair_sched_class = { .enqueue_task = enqueue_task_fair, .dequeue_task = dequeue_task_fair, .yield_task = yield_task_fair, + .yield_to_task = yield_to_task_fair, .check_preempt_curr = check_preempt_wakeup, @@ -3935,6 +4308,7 @@ static const struct sched_class fair_sched_class = { .task_fork = task_fork_fair, .prio_changed = prio_changed_fair, + .switched_from = switched_from_fair, .switched_to = switched_to_fair, .get_rr_interval = get_rr_interval_fair, diff --git a/kernel/sched_features.h b/kernel/sched_features.h index 185f920ec1a..be40f7371ee 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -52,8 +52,6 @@ SCHED_FEAT(ARCH_POWER, 0) SCHED_FEAT(HRTICK, 0) SCHED_FEAT(DOUBLE_TICK, 0) SCHED_FEAT(LB_BIAS, 1) -SCHED_FEAT(LB_SHARES_UPDATE, 1) -SCHED_FEAT(ASYM_EFF_LOAD, 1) /* * Spin-wait on mutex acquisition when the mutex owner is running on @@ -66,3 +64,9 @@ SCHED_FEAT(OWNER_SPIN, 1) * Decrement CPU power based on irq activity */ SCHED_FEAT(NONIRQ_POWER, 1) + +/* + * Queue remote wakeups on the target CPU and process them + * using the scheduler IPI. Reduces rq->lock contention/bounces. + */ +SCHED_FEAT(TTWU_QUEUE, 1) diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c index 9fa0f402c87..0a51882534e 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched_idletask.c @@ -7,7 +7,7 @@ #ifdef CONFIG_SMP static int -select_task_rq_idle(struct rq *rq, struct task_struct *p, int sd_flag, int flags) +select_task_rq_idle(struct task_struct *p, int sd_flag, int flags) { return task_cpu(p); /* IDLE tasks as never migrated */ } @@ -52,31 +52,15 @@ static void set_curr_task_idle(struct rq *rq) { } -static void switched_to_idle(struct rq *rq, struct task_struct *p, - int running) +static void switched_to_idle(struct rq *rq, struct task_struct *p) { - /* Can this actually happen?? */ - if (running) - resched_task(rq->curr); - else - check_preempt_curr(rq, p, 0); + BUG(); } -static void prio_changed_idle(struct rq *rq, struct task_struct *p, - int oldprio, int running) +static void +prio_changed_idle(struct rq *rq, struct task_struct *p, int oldprio) { - /* This can happen for hot plug CPUS */ - - /* - * Reschedule if we are currently running on this runqueue and - * our priority decreased, or if we are not currently running on - * this runqueue and our priority is higher than the current's - */ - if (running) { - if (p->prio > oldprio) - resched_task(rq->curr); - } else - check_preempt_curr(rq, p, 0); + BUG(); } static unsigned int get_rr_interval_idle(struct rq *rq, struct task_struct *task) @@ -110,6 +94,4 @@ static const struct sched_class idle_sched_class = { .prio_changed = prio_changed_idle, .switched_to = switched_to_idle, - - /* no .task_new for idle tasks */ }; diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index bea7d79f7e9..64b2a37c07d 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -183,6 +183,25 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq) return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period); } +typedef struct task_group *rt_rq_iter_t; + +#define for_each_rt_rq(rt_rq, iter, rq) \ + for (iter = list_entry_rcu(task_groups.next, typeof(*iter), list); \ + (&iter->list != &task_groups) && \ + (rt_rq = iter->rt_rq[cpu_of(rq)]); \ + iter = list_entry_rcu(iter->list.next, typeof(*iter), list)) + +static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) +{ + list_add_rcu(&rt_rq->leaf_rt_rq_list, + &rq_of_rt_rq(rt_rq)->leaf_rt_rq_list); +} + +static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq) +{ + list_del_rcu(&rt_rq->leaf_rt_rq_list); +} + #define for_each_leaf_rt_rq(rt_rq, rq) \ list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list) @@ -199,11 +218,12 @@ static void dequeue_rt_entity(struct sched_rt_entity *rt_se); static void sched_rt_rq_enqueue(struct rt_rq *rt_rq) { - int this_cpu = smp_processor_id(); struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr; struct sched_rt_entity *rt_se; - rt_se = rt_rq->tg->rt_se[this_cpu]; + int cpu = cpu_of(rq_of_rt_rq(rt_rq)); + + rt_se = rt_rq->tg->rt_se[cpu]; if (rt_rq->rt_nr_running) { if (rt_se && !on_rt_rq(rt_se)) @@ -215,10 +235,10 @@ static void sched_rt_rq_enqueue(struct rt_rq *rt_rq) static void sched_rt_rq_dequeue(struct rt_rq *rt_rq) { - int this_cpu = smp_processor_id(); struct sched_rt_entity *rt_se; + int cpu = cpu_of(rq_of_rt_rq(rt_rq)); - rt_se = rt_rq->tg->rt_se[this_cpu]; + rt_se = rt_rq->tg->rt_se[cpu]; if (rt_se && on_rt_rq(rt_se)) dequeue_rt_entity(rt_se); @@ -276,6 +296,19 @@ static inline u64 sched_rt_period(struct rt_rq *rt_rq) return ktime_to_ns(def_rt_bandwidth.rt_period); } +typedef struct rt_rq *rt_rq_iter_t; + +#define for_each_rt_rq(rt_rq, iter, rq) \ + for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL) + +static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq) +{ +} + +static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq) +{ +} + #define for_each_leaf_rt_rq(rt_rq, rq) \ for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL) @@ -382,12 +415,13 @@ next: static void __disable_runtime(struct rq *rq) { struct root_domain *rd = rq->rd; + rt_rq_iter_t iter; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) return; - for_each_leaf_rt_rq(rt_rq, rq) { + for_each_rt_rq(rt_rq, iter, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); s64 want; int i; @@ -467,6 +501,7 @@ static void disable_runtime(struct rq *rq) static void __enable_runtime(struct rq *rq) { + rt_rq_iter_t iter; struct rt_rq *rt_rq; if (unlikely(!scheduler_running)) @@ -475,7 +510,7 @@ static void __enable_runtime(struct rq *rq) /* * Reset each runqueue's bandwidth settings */ - for_each_leaf_rt_rq(rt_rq, rq) { + for_each_rt_rq(rt_rq, iter, rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); raw_spin_lock(&rt_b->rt_runtime_lock); @@ -542,12 +577,22 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun) if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) { rt_rq->rt_throttled = 0; enqueue = 1; + + /* + * Force a clock update if the CPU was idle, + * lest wakeup -> unthrottle time accumulate. + */ + if (rt_rq->rt_nr_running && rq->curr == rq->idle) + rq->skip_clock_update = -1; } if (rt_rq->rt_time || rt_rq->rt_nr_running) idle = 0; raw_spin_unlock(&rt_rq->rt_runtime_lock); - } else if (rt_rq->rt_nr_running) + } else if (rt_rq->rt_nr_running) { idle = 0; + if (!rt_rq_throttled(rt_rq)) + enqueue = 1; + } if (enqueue) sched_rt_rq_enqueue(rt_rq); @@ -606,7 +651,7 @@ static void update_curr_rt(struct rq *rq) struct rt_rq *rt_rq = rt_rq_of_se(rt_se); u64 delta_exec; - if (!task_has_rt_policy(curr)) + if (curr->sched_class != &rt_sched_class) return; delta_exec = rq->clock_task - curr->se.exec_start; @@ -825,6 +870,9 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head) if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running)) return; + if (!rt_rq->rt_nr_running) + list_add_leaf_rt_rq(rt_rq); + if (head) list_add(&rt_se->run_list, queue); else @@ -844,6 +892,8 @@ static void __dequeue_rt_entity(struct sched_rt_entity *rt_se) __clear_bit(rt_se_prio(rt_se), array->bitmap); dec_rt_tasks(rt_se, rt_rq); + if (!rt_rq->rt_nr_running) + list_del_leaf_rt_rq(rt_rq); } /* @@ -949,13 +999,23 @@ static void yield_task_rt(struct rq *rq) static int find_lowest_rq(struct task_struct *task); static int -select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags) +select_task_rq_rt(struct task_struct *p, int sd_flag, int flags) { + struct task_struct *curr; + struct rq *rq; + int cpu; + if (sd_flag != SD_BALANCE_WAKE) return smp_processor_id(); + cpu = task_cpu(p); + rq = cpu_rq(cpu); + + rcu_read_lock(); + curr = ACCESS_ONCE(rq->curr); /* unlocked access */ + /* - * If the current task is an RT task, then + * If the current task on @p's runqueue is an RT task, then * try to see if we can wake this RT task up on another * runqueue. Otherwise simply start this RT task * on its current runqueue. @@ -969,21 +1029,25 @@ select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags) * lock? * * For equal prio tasks, we just let the scheduler sort it out. + * + * Otherwise, just let it ride on the affined RQ and the + * post-schedule router will push the preempted task away + * + * This test is optimistic, if we get it wrong the load-balancer + * will have to sort it out. */ - if (unlikely(rt_task(rq->curr)) && - (rq->curr->rt.nr_cpus_allowed < 2 || - rq->curr->prio < p->prio) && + if (curr && unlikely(rt_task(curr)) && + (curr->rt.nr_cpus_allowed < 2 || + curr->prio < p->prio) && (p->rt.nr_cpus_allowed > 1)) { - int cpu = find_lowest_rq(p); + int target = find_lowest_rq(p); - return (cpu == -1) ? task_cpu(p) : cpu; + if (target != -1) + cpu = target; } + rcu_read_unlock(); - /* - * Otherwise, just let it ride on the affined RQ and the - * post-schedule router will push the preempted task away - */ - return task_cpu(p); + return cpu; } static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p) @@ -1108,7 +1172,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p) * The previous task needs to be made eligible for pushing * if it is still active */ - if (p->se.on_rq && p->rt.nr_cpus_allowed > 1) + if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1) enqueue_pushable_task(rq, p); } @@ -1259,7 +1323,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq) !cpumask_test_cpu(lowest_rq->cpu, &task->cpus_allowed) || task_running(rq, task) || - !task->se.on_rq)) { + !task->on_rq)) { raw_spin_unlock(&lowest_rq->lock); lowest_rq = NULL; @@ -1293,7 +1357,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq) BUG_ON(task_current(rq, p)); BUG_ON(p->rt.nr_cpus_allowed <= 1); - BUG_ON(!p->se.on_rq); + BUG_ON(!p->on_rq); BUG_ON(!rt_task(p)); return p; @@ -1350,7 +1414,7 @@ retry: task = pick_next_pushable_task(rq); if (task_cpu(next_task) == rq->cpu && task == next_task) { /* - * If we get here, the task hasnt moved at all, but + * If we get here, the task hasn't moved at all, but * it has failed to push. We will not try again, * since the other cpus will pull from us when they * are ready. @@ -1439,7 +1503,7 @@ static int pull_rt_task(struct rq *this_rq) */ if (p && (p->prio < this_rq->rt.highest_prio.curr)) { WARN_ON(p == src_rq->curr); - WARN_ON(!p->se.on_rq); + WARN_ON(!p->on_rq); /* * There's a chance that p is higher in priority @@ -1460,7 +1524,7 @@ static int pull_rt_task(struct rq *this_rq) /* * We continue with the search, just in * case there's an even higher prio task - * in another runqueue. (low likelyhood + * in another runqueue. (low likelihood * but possible) */ } @@ -1510,7 +1574,7 @@ static void set_cpus_allowed_rt(struct task_struct *p, * Update the migration status of the RQ if we have an RT task * which is running AND changing its weight value. */ - if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) { + if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) { struct rq *rq = task_rq(p); if (!task_current(rq, p)) { @@ -1571,8 +1635,7 @@ static void rq_offline_rt(struct rq *rq) * When switch from the rt queue, we bring ourselves to a position * that we might want to pull RT tasks from other runqueues. */ -static void switched_from_rt(struct rq *rq, struct task_struct *p, - int running) +static void switched_from_rt(struct rq *rq, struct task_struct *p) { /* * If there are other RT tasks then we will reschedule @@ -1581,7 +1644,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p, * we may need to handle the pulling of RT tasks * now. */ - if (!rq->rt.rt_nr_running) + if (p->on_rq && !rq->rt.rt_nr_running) pull_rt_task(rq); } @@ -1600,8 +1663,7 @@ static inline void init_sched_rt_class(void) * with RT tasks. In this case we try to push them off to * other runqueues. */ -static void switched_to_rt(struct rq *rq, struct task_struct *p, - int running) +static void switched_to_rt(struct rq *rq, struct task_struct *p) { int check_resched = 1; @@ -1612,7 +1674,7 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p, * If that current running task is also an RT task * then see if we can move to another run queue. */ - if (!running) { + if (p->on_rq && rq->curr != p) { #ifdef CONFIG_SMP if (rq->rt.overloaded && push_rt_task(rq) && /* Don't resched if we changed runqueues */ @@ -1628,10 +1690,13 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p, * Priority of the task has changed. This may cause * us to initiate a push or pull. */ -static void prio_changed_rt(struct rq *rq, struct task_struct *p, - int oldprio, int running) +static void +prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio) { - if (running) { + if (!p->on_rq) + return; + + if (rq->curr == p) { #ifdef CONFIG_SMP /* * If our priority decreases while running, we @@ -1767,10 +1832,11 @@ extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); static void print_rt_stats(struct seq_file *m, int cpu) { + rt_rq_iter_t iter; struct rt_rq *rt_rq; rcu_read_lock(); - for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu)) + for_each_rt_rq(rt_rq, iter, cpu_rq(cpu)) print_rt_rq(m, cpu, rt_rq); rcu_read_unlock(); } diff --git a/kernel/sched_stoptask.c b/kernel/sched_stoptask.c index 45bddc0c104..6f437632afa 100644 --- a/kernel/sched_stoptask.c +++ b/kernel/sched_stoptask.c @@ -9,8 +9,7 @@ #ifdef CONFIG_SMP static int -select_task_rq_stop(struct rq *rq, struct task_struct *p, - int sd_flag, int flags) +select_task_rq_stop(struct task_struct *p, int sd_flag, int flags) { return task_cpu(p); /* stop tasks as never migrate */ } @@ -19,14 +18,14 @@ select_task_rq_stop(struct rq *rq, struct task_struct *p, static void check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags) { - resched_task(rq->curr); /* we preempt everything */ + /* we're never preempted */ } static struct task_struct *pick_next_task_stop(struct rq *rq) { struct task_struct *stop = rq->stop; - if (stop && stop->state == TASK_RUNNING) + if (stop && stop->on_rq) return stop; return NULL; @@ -59,14 +58,13 @@ static void set_curr_task_stop(struct rq *rq) { } -static void switched_to_stop(struct rq *rq, struct task_struct *p, - int running) +static void switched_to_stop(struct rq *rq, struct task_struct *p) { BUG(); /* its impossible to change to this class */ } -static void prio_changed_stop(struct rq *rq, struct task_struct *p, - int oldprio, int running) +static void +prio_changed_stop(struct rq *rq, struct task_struct *p, int oldprio) { BUG(); /* how!?, what priority? */ } @@ -103,6 +101,4 @@ static const struct sched_class stop_sched_class = { .prio_changed = prio_changed_stop, .switched_to = switched_to_stop, - - /* no .task_new for stop tasks */ }; diff --git a/kernel/signal.c b/kernel/signal.c index 4e3cff10fdc..7165af5f1b1 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -226,7 +226,7 @@ static inline void print_dropped_signal(int sig) /* * allocate a new signal queue record * - this may be called without locks if and only if t == current, otherwise an - * appopriate lock must be held to stop the target task from exiting + * appropriate lock must be held to stop the target task from exiting */ static struct sigqueue * __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit) @@ -375,15 +375,15 @@ int unhandled_signal(struct task_struct *tsk, int sig) return !tracehook_consider_fatal_signal(tsk, sig); } - -/* Notify the system that a driver wants to block all signals for this +/* + * Notify the system that a driver wants to block all signals for this * process, and wants to be notified if any signals at all were to be * sent/acted upon. If the notifier routine returns non-zero, then the * signal will be acted upon after all. If the notifier routine returns 0, * then then signal will be blocked. Only one block per process is * allowed. priv is a pointer to private data that the notifier routine - * can use to determine if the signal should be blocked or not. */ - + * can use to determine if the signal should be blocked or not. + */ void block_all_signals(int (*notifier)(void *priv), void *priv, sigset_t *mask) { @@ -434,9 +434,10 @@ still_pending: copy_siginfo(info, &first->info); __sigqueue_free(first); } else { - /* Ok, it wasn't in the queue. This must be - a fast-pathed signal or we must have been - out of queue space. So zero out the info. + /* + * Ok, it wasn't in the queue. This must be + * a fast-pathed signal or we must have been + * out of queue space. So zero out the info. */ info->si_signo = sig; info->si_errno = 0; @@ -468,7 +469,7 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, } /* - * Dequeue a signal and return the element to the caller, which is + * Dequeue a signal and return the element to the caller, which is * expected to free it. * * All callers have to hold the siglock. @@ -490,7 +491,7 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info) * itimers are process shared and we restart periodic * itimers in the signal delivery path to prevent DoS * attacks in the high resolution timer case. This is - * compliant with the old way of self restarting + * compliant with the old way of self-restarting * itimers, as the SIGALRM is a legacy signal and only * queued once. Changing the restart behaviour to * restart the timer in the signal dequeue path is @@ -636,13 +637,33 @@ static inline bool si_fromuser(const struct siginfo *info) } /* + * called with RCU read lock from check_kill_permission() + */ +static int kill_ok_by_cred(struct task_struct *t) +{ + const struct cred *cred = current_cred(); + const struct cred *tcred = __task_cred(t); + + if (cred->user->user_ns == tcred->user->user_ns && + (cred->euid == tcred->suid || + cred->euid == tcred->uid || + cred->uid == tcred->suid || + cred->uid == tcred->uid)) + return 1; + + if (ns_capable(tcred->user->user_ns, CAP_KILL)) + return 1; + + return 0; +} + +/* * Bad permissions for sending the signal * - the caller must hold the RCU read lock */ static int check_kill_permission(int sig, struct siginfo *info, struct task_struct *t) { - const struct cred *cred, *tcred; struct pid *sid; int error; @@ -656,14 +677,8 @@ static int check_kill_permission(int sig, struct siginfo *info, if (error) return error; - cred = current_cred(); - tcred = __task_cred(t); if (!same_thread_group(current, t) && - (cred->euid ^ tcred->suid) && - (cred->euid ^ tcred->uid) && - (cred->uid ^ tcred->suid) && - (cred->uid ^ tcred->uid) && - !capable(CAP_KILL)) { + !kill_ok_by_cred(t)) { switch (sig) { case SIGCONT: sid = task_session(t); @@ -909,14 +924,15 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t, if (info == SEND_SIG_FORCED) goto out_set; - /* Real-time signals must be queued if sent by sigqueue, or - some other real-time mechanism. It is implementation - defined whether kill() does so. We attempt to do so, on - the principle of least surprise, but since kill is not - allowed to fail with EAGAIN when low on memory we just - make sure at least one signal gets delivered and don't - pass on the info struct. */ - + /* + * Real-time signals must be queued if sent by sigqueue, or + * some other real-time mechanism. It is implementation + * defined whether kill() does so. We attempt to do so, on + * the principle of least surprise, but since kill is not + * allowed to fail with EAGAIN when low on memory we just + * make sure at least one signal gets delivered and don't + * pass on the info struct. + */ if (sig < SIGRTMIN) override_rlimit = (is_si_special(info) || info->si_code >= 0); else @@ -1187,8 +1203,7 @@ retry: return error; } -int -kill_proc_info(int sig, struct siginfo *info, pid_t pid) +int kill_proc_info(int sig, struct siginfo *info, pid_t pid) { int error; rcu_read_lock(); @@ -1285,8 +1300,7 @@ static int kill_something_info(int sig, struct siginfo *info, pid_t pid) * These are for backward compatibility with the rest of the kernel source. */ -int -send_sig_info(int sig, struct siginfo *info, struct task_struct *p) +int send_sig_info(int sig, struct siginfo *info, struct task_struct *p) { /* * Make sure legacy kernel users don't send in bad values @@ -1354,7 +1368,7 @@ EXPORT_SYMBOL(kill_pid); * These functions support sending signals using preallocated sigqueue * structures. This is needed "because realtime applications cannot * afford to lose notifications of asynchronous events, like timer - * expirations or I/O completions". In the case of Posix Timers + * expirations or I/O completions". In the case of POSIX Timers * we allocate the sigqueue structure from the timer_create. If this * allocation fails we are able to report the failure to the application * with an EAGAIN error. @@ -1539,7 +1553,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why) info.si_signo = SIGCHLD; info.si_errno = 0; /* - * see comment in do_notify_parent() abot the following 3 lines + * see comment in do_notify_parent() about the following 4 lines */ rcu_read_lock(); info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns); @@ -1597,7 +1611,7 @@ static inline int may_ptrace_stop(void) } /* - * Return nonzero if there is a SIGKILL that should be waking us up. + * Return non-zero if there is a SIGKILL that should be waking us up. * Called with the siglock held. */ static int sigkill_pending(struct task_struct *tsk) @@ -1721,7 +1735,7 @@ void ptrace_notify(int exit_code) /* * This performs the stopping for SIGSTOP and other stop signals. * We have to stop all threads in the thread group. - * Returns nonzero if we've actually stopped and released the siglock. + * Returns non-zero if we've actually stopped and released the siglock. * Returns zero if we didn't stop and still hold the siglock. */ static int do_signal_stop(int signr) @@ -1809,10 +1823,12 @@ static int ptrace_signal(int signr, siginfo_t *info, current->exit_code = 0; - /* Update the siginfo structure if the signal has - changed. If the debugger wanted something - specific in the siginfo structure then it should - have updated *info via PTRACE_SETSIGINFO. */ + /* + * Update the siginfo structure if the signal has + * changed. If the debugger wanted something + * specific in the siginfo structure then it should + * have updated *info via PTRACE_SETSIGINFO. + */ if (signr != info->si_signo) { info->si_signo = signr; info->si_errno = 0; @@ -1871,7 +1887,7 @@ relock: for (;;) { struct k_sigaction *ka; /* - * Tracing can induce an artifical signal and choose sigaction. + * Tracing can induce an artificial signal and choose sigaction. * The return value in @signr determines the default action, * but @info->si_signo is the signal number we will report. */ @@ -2020,7 +2036,8 @@ void exit_signals(struct task_struct *tsk) if (!signal_pending(tsk)) goto out; - /* It could be that __group_complete_signal() choose us to + /* + * It could be that __group_complete_signal() choose us to * notify about group-wide signal. Another thread should be * woken now to take the signal since we will not. */ @@ -2058,6 +2075,9 @@ EXPORT_SYMBOL(unblock_all_signals); * System call entry points. */ +/** + * sys_restart_syscall - restart a system call + */ SYSCALL_DEFINE0(restart_syscall) { struct restart_block *restart = ¤t_thread_info()->restart_block; @@ -2111,6 +2131,13 @@ int sigprocmask(int how, sigset_t *set, sigset_t *oldset) return error; } +/** + * sys_rt_sigprocmask - change the list of currently blocked signals + * @how: whether to add, remove, or set signals + * @set: stores pending signals + * @oset: previous value of signal mask if non-null + * @sigsetsize: size of sigset_t type + */ SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, set, sigset_t __user *, oset, size_t, sigsetsize) { @@ -2169,8 +2196,14 @@ long do_sigpending(void __user *set, unsigned long sigsetsize) out: return error; -} +} +/** + * sys_rt_sigpending - examine a pending signal that has been raised + * while blocked + * @set: stores pending signals + * @sigsetsize: size of sigset_t type or larger + */ SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, set, size_t, sigsetsize) { return do_sigpending(set, sigsetsize); @@ -2219,9 +2252,9 @@ int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) err |= __put_user(from->si_trapno, &to->si_trapno); #endif #ifdef BUS_MCEERR_AO - /* + /* * Other callers might not initialize the si_lsb field, - * so check explicitely for the right codes here. + * so check explicitly for the right codes here. */ if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO) err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb); @@ -2250,6 +2283,14 @@ int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) #endif +/** + * sys_rt_sigtimedwait - synchronously wait for queued signals specified + * in @uthese + * @uthese: queued signals to wait for + * @uinfo: if non-null, the signal's siginfo is returned here + * @uts: upper bound on process time suspension + * @sigsetsize: size of sigset_t type + */ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, siginfo_t __user *, uinfo, const struct timespec __user *, uts, size_t, sigsetsize) @@ -2266,7 +2307,7 @@ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, if (copy_from_user(&these, uthese, sizeof(these))) return -EFAULT; - + /* * Invert the set of allowed signals to get those we * want to block. @@ -2291,9 +2332,11 @@ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, + (ts.tv_sec || ts.tv_nsec)); if (timeout) { - /* None ready -- temporarily unblock those we're + /* + * None ready -- temporarily unblock those we're * interested while we are sleeping in so that we'll - * be awakened when they arrive. */ + * be awakened when they arrive. + */ current->real_blocked = current->blocked; sigandsets(¤t->blocked, ¤t->blocked, &these); recalc_sigpending(); @@ -2325,6 +2368,11 @@ SYSCALL_DEFINE4(rt_sigtimedwait, const sigset_t __user *, uthese, return ret; } +/** + * sys_kill - send a signal to a process + * @pid: the PID of the process + * @sig: signal to be sent + */ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig) { struct siginfo info; @@ -2400,7 +2448,11 @@ SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig) return do_tkill(tgid, pid, sig); } -/* +/** + * sys_tkill - send signal to one specific task + * @pid: the PID of the task + * @sig: signal to be sent + * * Send a signal to only one task, even if it's a CLONE_THREAD task. */ SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) @@ -2412,6 +2464,12 @@ SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig) return do_tkill(0, pid, sig); } +/** + * sys_rt_sigqueueinfo - send signal information to a signal + * @pid: the PID of the thread + * @sig: signal to be sent + * @uinfo: signal info to be sent + */ SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, siginfo_t __user *, uinfo) { @@ -2421,9 +2479,13 @@ SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig, return -EFAULT; /* Not even root can pretend to send signals from the kernel. - Nor can they impersonate a kill(), which adds source info. */ - if (info.si_code >= 0) + * Nor can they impersonate a kill()/tgkill(), which adds source info. + */ + if (info.si_code >= 0 || info.si_code == SI_TKILL) { + /* We used to allow any < 0 si_code */ + WARN_ON_ONCE(info.si_code < 0); return -EPERM; + } info.si_signo = sig; /* POSIX.1b doesn't mention process groups. */ @@ -2437,9 +2499,13 @@ long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info) return -EINVAL; /* Not even root can pretend to send signals from the kernel. - Nor can they impersonate a kill(), which adds source info. */ - if (info->si_code >= 0) + * Nor can they impersonate a kill()/tgkill(), which adds source info. + */ + if (info->si_code >= 0 || info->si_code == SI_TKILL) { + /* We used to allow any < 0 si_code */ + WARN_ON_ONCE(info->si_code < 0); return -EPERM; + } info->si_signo = sig; return do_send_specific(tgid, pid, sig, info); @@ -2531,12 +2597,11 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s error = -EINVAL; /* - * - * Note - this code used to test ss_flags incorrectly + * Note - this code used to test ss_flags incorrectly: * old code may have been written using ss_flags==0 * to mean ss_flags==SS_ONSTACK (as this was the only * way that worked) - this fix preserves that older - * mechanism + * mechanism. */ if (ss_flags != SS_DISABLE && ss_flags != SS_ONSTACK && ss_flags != 0) goto out; @@ -2570,6 +2635,10 @@ out: #ifdef __ARCH_WANT_SYS_SIGPENDING +/** + * sys_sigpending - examine pending signals + * @set: where mask of pending signal is returned + */ SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) { return do_sigpending(set, sizeof(*set)); @@ -2578,8 +2647,15 @@ SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) #endif #ifdef __ARCH_WANT_SYS_SIGPROCMASK -/* Some platforms have their own version with special arguments others - support only sys_rt_sigprocmask. */ +/** + * sys_sigprocmask - examine and change blocked signals + * @how: whether to add, remove, or set signals + * @set: signals to add or remove (if non-null) + * @oset: previous value of signal mask if non-null + * + * Some platforms have their own version with special arguments; + * others support only sys_rt_sigprocmask. + */ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, set, old_sigset_t __user *, oset) @@ -2632,6 +2708,13 @@ out: #endif /* __ARCH_WANT_SYS_SIGPROCMASK */ #ifdef __ARCH_WANT_SYS_RT_SIGACTION +/** + * sys_rt_sigaction - alter an action taken by a process + * @sig: signal to be sent + * @act: new sigaction + * @oact: used to save the previous sigaction + * @sigsetsize: size of sigset_t type + */ SYSCALL_DEFINE4(rt_sigaction, int, sig, const struct sigaction __user *, act, struct sigaction __user *, oact, @@ -2718,6 +2801,12 @@ SYSCALL_DEFINE0(pause) #endif #ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND +/** + * sys_rt_sigsuspend - replace the signal mask for a value with the + * @unewset value until a signal is received + * @unewset: new signal mask value + * @sigsetsize: size of sigset_t type + */ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) { sigset_t newset; diff --git a/kernel/smp.c b/kernel/smp.c index 12ed8b013e2..73a19519355 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -13,6 +13,7 @@ #include <linux/smp.h> #include <linux/cpu.h> +#ifdef CONFIG_USE_GENERIC_SMP_HELPERS static struct { struct list_head queue; raw_spinlock_t lock; @@ -193,23 +194,52 @@ void generic_smp_call_function_interrupt(void) */ list_for_each_entry_rcu(data, &call_function.queue, csd.list) { int refs; + smp_call_func_t func; - if (!cpumask_test_and_clear_cpu(cpu, data->cpumask)) + /* + * Since we walk the list without any locks, we might + * see an entry that was completed, removed from the + * list and is in the process of being reused. + * + * We must check that the cpu is in the cpumask before + * checking the refs, and both must be set before + * executing the callback on this cpu. + */ + + if (!cpumask_test_cpu(cpu, data->cpumask)) + continue; + + smp_rmb(); + + if (atomic_read(&data->refs) == 0) continue; - data->csd.func(data->csd.info); + func = data->csd.func; /* save for later warn */ + func(data->csd.info); + + /* + * If the cpu mask is not still set then func enabled + * interrupts (BUG), and this cpu took another smp call + * function interrupt and executed func(info) twice + * on this cpu. That nested execution decremented refs. + */ + if (!cpumask_test_and_clear_cpu(cpu, data->cpumask)) { + WARN(1, "%pf enabled interrupts and double executed\n", func); + continue; + } refs = atomic_dec_return(&data->refs); WARN_ON(refs < 0); - if (!refs) { - raw_spin_lock(&call_function.lock); - list_del_rcu(&data->csd.list); - raw_spin_unlock(&call_function.lock); - } if (refs) continue; + WARN_ON(!cpumask_empty(data->cpumask)); + + raw_spin_lock(&call_function.lock); + list_del_rcu(&data->csd.list); + raw_spin_unlock(&call_function.lock); + csd_unlock(&data->csd); } @@ -420,7 +450,7 @@ void smp_call_function_many(const struct cpumask *mask, { struct call_function_data *data; unsigned long flags; - int cpu, next_cpu, this_cpu = smp_processor_id(); + int refs, cpu, next_cpu, this_cpu = smp_processor_id(); /* * Can deadlock when called with interrupts disabled. @@ -429,9 +459,9 @@ void smp_call_function_many(const struct cpumask *mask, * can't happen. */ WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() - && !oops_in_progress); + && !oops_in_progress && !early_boot_irqs_disabled); - /* So, what's a CPU they want? Ignoring this one. */ + /* Try to fastpath. So, what's a CPU they want? Ignoring this one. */ cpu = cpumask_first_and(mask, cpu_online_mask); if (cpu == this_cpu) cpu = cpumask_next_and(cpu, mask, cpu_online_mask); @@ -454,11 +484,48 @@ void smp_call_function_many(const struct cpumask *mask, data = &__get_cpu_var(cfd_data); csd_lock(&data->csd); + /* This BUG_ON verifies our reuse assertions and can be removed */ + BUG_ON(atomic_read(&data->refs) || !cpumask_empty(data->cpumask)); + + /* + * The global call function queue list add and delete are protected + * by a lock, but the list is traversed without any lock, relying + * on the rcu list add and delete to allow safe concurrent traversal. + * We reuse the call function data without waiting for any grace + * period after some other cpu removes it from the global queue. + * This means a cpu might find our data block as it is being + * filled out. + * + * We hold off the interrupt handler on the other cpu by + * ordering our writes to the cpu mask vs our setting of the + * refs counter. We assert only the cpu owning the data block + * will set a bit in cpumask, and each bit will only be cleared + * by the subject cpu. Each cpu must first find its bit is + * set and then check that refs is set indicating the element is + * ready to be processed, otherwise it must skip the entry. + * + * On the previous iteration refs was set to 0 by another cpu. + * To avoid the use of transitivity, set the counter to 0 here + * so the wmb will pair with the rmb in the interrupt handler. + */ + atomic_set(&data->refs, 0); /* convert 3rd to 1st party write */ + data->csd.func = func; data->csd.info = info; + + /* Ensure 0 refs is visible before mask. Also orders func and info */ + smp_wmb(); + + /* We rely on the "and" being processed before the store */ cpumask_and(data->cpumask, mask, cpu_online_mask); cpumask_clear_cpu(this_cpu, data->cpumask); - atomic_set(&data->refs, cpumask_weight(data->cpumask)); + refs = cpumask_weight(data->cpumask); + + /* Some callers race with other cpus changing the passed mask */ + if (unlikely(!refs)) { + csd_unlock(&data->csd); + return; + } raw_spin_lock_irqsave(&call_function.lock, flags); /* @@ -467,6 +534,12 @@ void smp_call_function_many(const struct cpumask *mask, * will not miss any other list entries: */ list_add_rcu(&data->csd.list, &call_function.queue); + /* + * We rely on the wmb() in list_add_rcu to complete our writes + * to the cpumask before this write to refs, which indicates + * data is on the list and is ready to be processed. + */ + atomic_set(&data->refs, refs); raw_spin_unlock_irqrestore(&call_function.lock, flags); /* @@ -529,3 +602,105 @@ void ipi_call_unlock_irq(void) { raw_spin_unlock_irq(&call_function.lock); } +#endif /* USE_GENERIC_SMP_HELPERS */ + +/* Setup configured maximum number of CPUs to activate */ +unsigned int setup_max_cpus = NR_CPUS; +EXPORT_SYMBOL(setup_max_cpus); + + +/* + * Setup routine for controlling SMP activation + * + * Command-line option of "nosmp" or "maxcpus=0" will disable SMP + * activation entirely (the MPS table probe still happens, though). + * + * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer + * greater than 0, limits the maximum number of CPUs activated in + * SMP mode to <NUM>. + */ + +void __weak arch_disable_smp_support(void) { } + +static int __init nosmp(char *str) +{ + setup_max_cpus = 0; + arch_disable_smp_support(); + + return 0; +} + +early_param("nosmp", nosmp); + +/* this is hard limit */ +static int __init nrcpus(char *str) +{ + int nr_cpus; + + get_option(&str, &nr_cpus); + if (nr_cpus > 0 && nr_cpus < nr_cpu_ids) + nr_cpu_ids = nr_cpus; + + return 0; +} + +early_param("nr_cpus", nrcpus); + +static int __init maxcpus(char *str) +{ + get_option(&str, &setup_max_cpus); + if (setup_max_cpus == 0) + arch_disable_smp_support(); + + return 0; +} + +early_param("maxcpus", maxcpus); + +/* Setup number of possible processor ids */ +int nr_cpu_ids __read_mostly = NR_CPUS; +EXPORT_SYMBOL(nr_cpu_ids); + +/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */ +void __init setup_nr_cpu_ids(void) +{ + nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1; +} + +/* Called by boot processor to activate the rest. */ +void __init smp_init(void) +{ + unsigned int cpu; + + /* FIXME: This should be done in userspace --RR */ + for_each_present_cpu(cpu) { + if (num_online_cpus() >= setup_max_cpus) + break; + if (!cpu_online(cpu)) + cpu_up(cpu); + } + + /* Any cleanup work */ + printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus()); + smp_cpus_done(setup_max_cpus); +} + +/* + * Call a function on all processors. May be used during early boot while + * early_boot_irqs_disabled is set. Use local_irq_save/restore() instead + * of local_irq_disable/enable(). + */ +int on_each_cpu(void (*func) (void *info), void *info, int wait) +{ + unsigned long flags; + int ret = 0; + + preempt_disable(); + ret = smp_call_function(func, info, wait); + local_irq_save(flags); + func(info); + local_irq_restore(flags); + preempt_enable(); + return ret; +} +EXPORT_SYMBOL(on_each_cpu); diff --git a/kernel/softirq.c b/kernel/softirq.c index 18f4be0d5fe..13960170cad 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -54,11 +54,11 @@ EXPORT_SYMBOL(irq_stat); static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp; -static DEFINE_PER_CPU(struct task_struct *, ksoftirqd); +DEFINE_PER_CPU(struct task_struct *, ksoftirqd); char *softirq_to_name[NR_SOFTIRQS] = { "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL", - "TASKLET", "SCHED", "HRTIMER", "RCU" + "TASKLET", "SCHED", "HRTIMER" }; /* @@ -70,7 +70,7 @@ char *softirq_to_name[NR_SOFTIRQS] = { static void wakeup_softirqd(void) { /* Interrupts are disabled: no need to stop preemption */ - struct task_struct *tsk = __get_cpu_var(ksoftirqd); + struct task_struct *tsk = __this_cpu_read(ksoftirqd); if (tsk && tsk->state != TASK_RUNNING) wake_up_process(tsk); @@ -311,9 +311,21 @@ void irq_enter(void) } #ifdef __ARCH_IRQ_EXIT_IRQS_DISABLED -# define invoke_softirq() __do_softirq() +static inline void invoke_softirq(void) +{ + if (!force_irqthreads) + __do_softirq(); + else + wakeup_softirqd(); +} #else -# define invoke_softirq() do_softirq() +static inline void invoke_softirq(void) +{ + if (!force_irqthreads) + do_softirq(); + else + wakeup_softirqd(); +} #endif /* @@ -388,8 +400,8 @@ void __tasklet_schedule(struct tasklet_struct *t) local_irq_save(flags); t->next = NULL; - *__get_cpu_var(tasklet_vec).tail = t; - __get_cpu_var(tasklet_vec).tail = &(t->next); + *__this_cpu_read(tasklet_vec.tail) = t; + __this_cpu_write(tasklet_vec.tail, &(t->next)); raise_softirq_irqoff(TASKLET_SOFTIRQ); local_irq_restore(flags); } @@ -402,8 +414,8 @@ void __tasklet_hi_schedule(struct tasklet_struct *t) local_irq_save(flags); t->next = NULL; - *__get_cpu_var(tasklet_hi_vec).tail = t; - __get_cpu_var(tasklet_hi_vec).tail = &(t->next); + *__this_cpu_read(tasklet_hi_vec.tail) = t; + __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); raise_softirq_irqoff(HI_SOFTIRQ); local_irq_restore(flags); } @@ -414,8 +426,8 @@ void __tasklet_hi_schedule_first(struct tasklet_struct *t) { BUG_ON(!irqs_disabled()); - t->next = __get_cpu_var(tasklet_hi_vec).head; - __get_cpu_var(tasklet_hi_vec).head = t; + t->next = __this_cpu_read(tasklet_hi_vec.head); + __this_cpu_write(tasklet_hi_vec.head, t); __raise_softirq_irqoff(HI_SOFTIRQ); } @@ -426,9 +438,9 @@ static void tasklet_action(struct softirq_action *a) struct tasklet_struct *list; local_irq_disable(); - list = __get_cpu_var(tasklet_vec).head; - __get_cpu_var(tasklet_vec).head = NULL; - __get_cpu_var(tasklet_vec).tail = &__get_cpu_var(tasklet_vec).head; + list = __this_cpu_read(tasklet_vec.head); + __this_cpu_write(tasklet_vec.head, NULL); + __this_cpu_write(tasklet_vec.tail, &__get_cpu_var(tasklet_vec).head); local_irq_enable(); while (list) { @@ -449,8 +461,8 @@ static void tasklet_action(struct softirq_action *a) local_irq_disable(); t->next = NULL; - *__get_cpu_var(tasklet_vec).tail = t; - __get_cpu_var(tasklet_vec).tail = &(t->next); + *__this_cpu_read(tasklet_vec.tail) = t; + __this_cpu_write(tasklet_vec.tail, &(t->next)); __raise_softirq_irqoff(TASKLET_SOFTIRQ); local_irq_enable(); } @@ -461,9 +473,9 @@ static void tasklet_hi_action(struct softirq_action *a) struct tasklet_struct *list; local_irq_disable(); - list = __get_cpu_var(tasklet_hi_vec).head; - __get_cpu_var(tasklet_hi_vec).head = NULL; - __get_cpu_var(tasklet_hi_vec).tail = &__get_cpu_var(tasklet_hi_vec).head; + list = __this_cpu_read(tasklet_hi_vec.head); + __this_cpu_write(tasklet_hi_vec.head, NULL); + __this_cpu_write(tasklet_hi_vec.tail, &__get_cpu_var(tasklet_hi_vec).head); local_irq_enable(); while (list) { @@ -484,8 +496,8 @@ static void tasklet_hi_action(struct softirq_action *a) local_irq_disable(); t->next = NULL; - *__get_cpu_var(tasklet_hi_vec).tail = t; - __get_cpu_var(tasklet_hi_vec).tail = &(t->next); + *__this_cpu_read(tasklet_hi_vec.tail) = t; + __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); __raise_softirq_irqoff(HI_SOFTIRQ); local_irq_enable(); } @@ -555,7 +567,7 @@ static void __tasklet_hrtimer_trampoline(unsigned long data) /** * tasklet_hrtimer_init - Init a tasklet/hrtimer combo for softirq callbacks * @ttimer: tasklet_hrtimer which is initialized - * @function: hrtimer callback funtion which gets called from softirq context + * @function: hrtimer callback function which gets called from softirq context * @which_clock: clock id (CLOCK_MONOTONIC/CLOCK_REALTIME) * @mode: hrtimer mode (HRTIMER_MODE_ABS/HRTIMER_MODE_REL) */ @@ -721,7 +733,6 @@ static int run_ksoftirqd(void * __bind_cpu) { set_current_state(TASK_INTERRUPTIBLE); - current->flags |= PF_KSOFTIRQD; while (!kthread_should_stop()) { preempt_disable(); if (!local_softirq_pending()) { @@ -738,7 +749,10 @@ static int run_ksoftirqd(void * __bind_cpu) don't process */ if (cpu_is_offline((long)__bind_cpu)) goto wait_to_die; - do_softirq(); + local_irq_disable(); + if (local_softirq_pending()) + __do_softirq(); + local_irq_enable(); preempt_enable_no_resched(); cond_resched(); preempt_disable(); @@ -802,16 +816,16 @@ static void takeover_tasklets(unsigned int cpu) /* Find end, append list for that CPU. */ if (&per_cpu(tasklet_vec, cpu).head != per_cpu(tasklet_vec, cpu).tail) { - *(__get_cpu_var(tasklet_vec).tail) = per_cpu(tasklet_vec, cpu).head; - __get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).tail; + *__this_cpu_read(tasklet_vec.tail) = per_cpu(tasklet_vec, cpu).head; + this_cpu_write(tasklet_vec.tail, per_cpu(tasklet_vec, cpu).tail); per_cpu(tasklet_vec, cpu).head = NULL; per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head; } raise_softirq_irqoff(TASKLET_SOFTIRQ); if (&per_cpu(tasklet_hi_vec, cpu).head != per_cpu(tasklet_hi_vec, cpu).tail) { - *__get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).head; - __get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).tail; + *__this_cpu_read(tasklet_hi_vec.tail) = per_cpu(tasklet_hi_vec, cpu).head; + __this_cpu_write(tasklet_hi_vec.tail, per_cpu(tasklet_hi_vec, cpu).tail); per_cpu(tasklet_hi_vec, cpu).head = NULL; per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head; } @@ -831,7 +845,10 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb, switch (action) { case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: - p = kthread_create(run_ksoftirqd, hcpu, "ksoftirqd/%d", hotcpu); + p = kthread_create_on_node(run_ksoftirqd, + hcpu, + cpu_to_node(hotcpu), + "ksoftirqd/%d", hotcpu); if (IS_ERR(p)) { printk("ksoftirqd for %i failed\n", hotcpu); return notifier_from_errno(PTR_ERR(p)); @@ -853,7 +870,9 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb, cpumask_any(cpu_online_mask)); case CPU_DEAD: case CPU_DEAD_FROZEN: { - struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + static const struct sched_param param = { + .sched_priority = MAX_RT_PRIO-1 + }; p = per_cpu(ksoftirqd, hotcpu); per_cpu(ksoftirqd, hotcpu) = NULL; @@ -883,25 +902,6 @@ static __init int spawn_ksoftirqd(void) } early_initcall(spawn_ksoftirqd); -#ifdef CONFIG_SMP -/* - * Call a function on all processors - */ -int on_each_cpu(void (*func) (void *info), void *info, int wait) -{ - int ret = 0; - - preempt_disable(); - ret = smp_call_function(func, info, wait); - local_irq_disable(); - func(info); - local_irq_enable(); - preempt_enable(); - return ret; -} -EXPORT_SYMBOL(on_each_cpu); -#endif - /* * [ These __weak aliases are kept in a separate compilation unit, so that * GCC does not inline them incorrectly. ] diff --git a/kernel/srcu.c b/kernel/srcu.c index c71e0750053..73ce23feaea 100644 --- a/kernel/srcu.c +++ b/kernel/srcu.c @@ -31,6 +31,7 @@ #include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/smp.h> +#include <linux/delay.h> #include <linux/srcu.h> static int init_srcu_struct_fields(struct srcu_struct *sp) @@ -155,6 +156,16 @@ void __srcu_read_unlock(struct srcu_struct *sp, int idx) EXPORT_SYMBOL_GPL(__srcu_read_unlock); /* + * We use an adaptive strategy for synchronize_srcu() and especially for + * synchronize_srcu_expedited(). We spin for a fixed time period + * (defined below) to allow SRCU readers to exit their read-side critical + * sections. If there are still some readers after 10 microseconds, + * we repeatedly block for 1-millisecond time periods. This approach + * has done well in testing, so there is no need for a config parameter. + */ +#define SYNCHRONIZE_SRCU_READER_DELAY 10 + +/* * Helper function for synchronize_srcu() and synchronize_srcu_expedited(). */ static void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void)) @@ -203,9 +214,15 @@ static void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void)) * all srcu_read_lock() calls using the old counters have completed. * Their corresponding critical sections might well be still * executing, but the srcu_read_lock() primitives themselves - * will have finished executing. + * will have finished executing. We initially give readers + * an arbitrarily chosen 10 microseconds to get out of their + * SRCU read-side critical sections, then loop waiting 1/HZ + * seconds per iteration. The 10-microsecond value has done + * very well in testing. */ + if (srcu_readers_active_idx(sp, idx)) + udelay(SYNCHRONIZE_SRCU_READER_DELAY); while (srcu_readers_active_idx(sp, idx)) schedule_timeout_interruptible(1); diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 2df820b03be..e3516b29076 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -301,8 +301,10 @@ static int __cpuinit cpu_stop_cpu_callback(struct notifier_block *nfb, case CPU_UP_PREPARE: BUG_ON(stopper->thread || stopper->enabled || !list_empty(&stopper->works)); - p = kthread_create(cpu_stopper_thread, stopper, "migration/%d", - cpu); + p = kthread_create_on_node(cpu_stopper_thread, + stopper, + cpu_to_node(cpu), + "migration/%d", cpu); if (IS_ERR(p)) return notifier_from_errno(PTR_ERR(p)); get_task_struct(p); diff --git a/kernel/sys.c b/kernel/sys.c index 7f5a0cd296a..e4128b278f2 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -37,12 +37,15 @@ #include <linux/ptrace.h> #include <linux/fs_struct.h> #include <linux/gfp.h> +#include <linux/syscore_ops.h> #include <linux/compat.h> #include <linux/syscalls.h> #include <linux/kprobes.h> #include <linux/user_namespace.h> +#include <linux/kmsg_dump.h> + #include <asm/uaccess.h> #include <asm/io.h> #include <asm/unistd.h> @@ -117,16 +120,33 @@ EXPORT_SYMBOL(cad_pid); void (*pm_power_off_prepare)(void); /* + * Returns true if current's euid is same as p's uid or euid, + * or has CAP_SYS_NICE to p's user_ns. + * + * Called with rcu_read_lock, creds are safe + */ +static bool set_one_prio_perm(struct task_struct *p) +{ + const struct cred *cred = current_cred(), *pcred = __task_cred(p); + + if (pcred->user->user_ns == cred->user->user_ns && + (pcred->uid == cred->euid || + pcred->euid == cred->euid)) + return true; + if (ns_capable(pcred->user->user_ns, CAP_SYS_NICE)) + return true; + return false; +} + +/* * set the priority of a task * - the caller must hold the RCU read lock */ static int set_one_prio(struct task_struct *p, int niceval, int error) { - const struct cred *cred = current_cred(), *pcred = __task_cred(p); int no_nice; - if (pcred->uid != cred->euid && - pcred->euid != cred->euid && !capable(CAP_SYS_NICE)) { + if (!set_one_prio_perm(p)) { error = -EPERM; goto out; } @@ -285,6 +305,7 @@ out_unlock: */ void emergency_restart(void) { + kmsg_dump(KMSG_DUMP_EMERG); machine_emergency_restart(); } EXPORT_SYMBOL_GPL(emergency_restart); @@ -293,8 +314,9 @@ void kernel_restart_prepare(char *cmd) { blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); system_state = SYSTEM_RESTART; + usermodehelper_disable(); device_shutdown(); - sysdev_shutdown(); + syscore_shutdown(); } /** @@ -312,6 +334,7 @@ void kernel_restart(char *cmd) printk(KERN_EMERG "Restarting system.\n"); else printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); + kmsg_dump(KMSG_DUMP_RESTART); machine_restart(cmd); } EXPORT_SYMBOL_GPL(kernel_restart); @@ -321,6 +344,7 @@ static void kernel_shutdown_prepare(enum system_states state) blocking_notifier_call_chain(&reboot_notifier_list, (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); system_state = state; + usermodehelper_disable(); device_shutdown(); } /** @@ -331,8 +355,9 @@ static void kernel_shutdown_prepare(enum system_states state) void kernel_halt(void) { kernel_shutdown_prepare(SYSTEM_HALT); - sysdev_shutdown(); + syscore_shutdown(); printk(KERN_EMERG "System halted.\n"); + kmsg_dump(KMSG_DUMP_HALT); machine_halt(); } @@ -349,8 +374,9 @@ void kernel_power_off(void) if (pm_power_off_prepare) pm_power_off_prepare(); disable_nonboot_cpus(); - sysdev_shutdown(); + syscore_shutdown(); printk(KERN_EMERG "Power down.\n"); + kmsg_dump(KMSG_DUMP_POWEROFF); machine_power_off(); } EXPORT_SYMBOL_GPL(kernel_power_off); @@ -496,7 +522,7 @@ SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) if (rgid != (gid_t) -1) { if (old->gid == rgid || old->egid == rgid || - capable(CAP_SETGID)) + nsown_capable(CAP_SETGID)) new->gid = rgid; else goto error; @@ -505,7 +531,7 @@ SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) if (old->gid == egid || old->egid == egid || old->sgid == egid || - capable(CAP_SETGID)) + nsown_capable(CAP_SETGID)) new->egid = egid; else goto error; @@ -540,7 +566,7 @@ SYSCALL_DEFINE1(setgid, gid_t, gid) old = current_cred(); retval = -EPERM; - if (capable(CAP_SETGID)) + if (nsown_capable(CAP_SETGID)) new->gid = new->egid = new->sgid = new->fsgid = gid; else if (gid == old->gid || gid == old->sgid) new->egid = new->fsgid = gid; @@ -607,7 +633,7 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) new->uid = ruid; if (old->uid != ruid && old->euid != ruid && - !capable(CAP_SETUID)) + !nsown_capable(CAP_SETUID)) goto error; } @@ -616,7 +642,7 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) if (old->uid != euid && old->euid != euid && old->suid != euid && - !capable(CAP_SETUID)) + !nsown_capable(CAP_SETUID)) goto error; } @@ -664,7 +690,7 @@ SYSCALL_DEFINE1(setuid, uid_t, uid) old = current_cred(); retval = -EPERM; - if (capable(CAP_SETUID)) { + if (nsown_capable(CAP_SETUID)) { new->suid = new->uid = uid; if (uid != old->uid) { retval = set_user(new); @@ -706,7 +732,7 @@ SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) old = current_cred(); retval = -EPERM; - if (!capable(CAP_SETUID)) { + if (!nsown_capable(CAP_SETUID)) { if (ruid != (uid_t) -1 && ruid != old->uid && ruid != old->euid && ruid != old->suid) goto error; @@ -770,7 +796,7 @@ SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) old = current_cred(); retval = -EPERM; - if (!capable(CAP_SETGID)) { + if (!nsown_capable(CAP_SETGID)) { if (rgid != (gid_t) -1 && rgid != old->gid && rgid != old->egid && rgid != old->sgid) goto error; @@ -830,7 +856,7 @@ SYSCALL_DEFINE1(setfsuid, uid_t, uid) if (uid == old->uid || uid == old->euid || uid == old->suid || uid == old->fsuid || - capable(CAP_SETUID)) { + nsown_capable(CAP_SETUID)) { if (uid != old_fsuid) { new->fsuid = uid; if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) @@ -863,7 +889,7 @@ SYSCALL_DEFINE1(setfsgid, gid_t, gid) if (gid == old->gid || gid == old->egid || gid == old->sgid || gid == old->fsgid || - capable(CAP_SETGID)) { + nsown_capable(CAP_SETGID)) { if (gid != old_fsgid) { new->fsgid = gid; goto change_okay; @@ -1080,8 +1106,10 @@ SYSCALL_DEFINE0(setsid) err = session; out: write_unlock_irq(&tasklist_lock); - if (err > 0) + if (err > 0) { proc_sid_connector(group_leader); + sched_autogroup_create_attach(group_leader); + } return err; } @@ -1169,8 +1197,9 @@ SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) int errno; char tmp[__NEW_UTS_LEN]; - if (!capable(CAP_SYS_ADMIN)) + if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) return -EPERM; + if (len < 0 || len > __NEW_UTS_LEN) return -EINVAL; down_write(&uts_sem); @@ -1218,7 +1247,7 @@ SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) int errno; char tmp[__NEW_UTS_LEN]; - if (!capable(CAP_SYS_ADMIN)) + if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) return -EPERM; if (len < 0 || len > __NEW_UTS_LEN) return -EINVAL; @@ -1333,6 +1362,8 @@ int do_prlimit(struct task_struct *tsk, unsigned int resource, rlim = tsk->signal->rlim + resource; task_lock(tsk->group_leader); if (new_rlim) { + /* Keep the capable check against init_user_ns until + cgroups can contain all limits */ if (new_rlim->rlim_max > rlim->rlim_max && !capable(CAP_SYS_RESOURCE)) retval = -EPERM; @@ -1376,18 +1407,22 @@ static int check_prlimit_permission(struct task_struct *task) { const struct cred *cred = current_cred(), *tcred; - tcred = __task_cred(task); - if ((cred->uid != tcred->euid || - cred->uid != tcred->suid || - cred->uid != tcred->uid || - cred->gid != tcred->egid || - cred->gid != tcred->sgid || - cred->gid != tcred->gid) && - !capable(CAP_SYS_RESOURCE)) { - return -EPERM; - } + if (current == task) + return 0; - return 0; + tcred = __task_cred(task); + if (cred->user->user_ns == tcred->user->user_ns && + (cred->uid == tcred->euid && + cred->uid == tcred->suid && + cred->uid == tcred->uid && + cred->gid == tcred->egid && + cred->gid == tcred->sgid && + cred->gid == tcred->gid)) + return 0; + if (ns_capable(tcred->user->user_ns, CAP_SYS_RESOURCE)) + return 0; + + return -EPERM; } SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index c782fe9924c..25cc41cd8f3 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -186,3 +186,8 @@ cond_syscall(sys_perf_event_open); /* fanotify! */ cond_syscall(sys_fanotify_init); cond_syscall(sys_fanotify_mark); + +/* open by handle */ +cond_syscall(sys_name_to_handle_at); +cond_syscall(sys_open_by_handle_at); +cond_syscall(compat_sys_open_by_handle_at); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index c33a1edb799..3dd0c46fa3b 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -24,6 +24,7 @@ #include <linux/slab.h> #include <linux/sysctl.h> #include <linux/signal.h> +#include <linux/printk.h> #include <linux/proc_fs.h> #include <linux/security.h> #include <linux/ctype.h> @@ -116,6 +117,7 @@ static int neg_one = -1; static int zero; static int __maybe_unused one = 1; static int __maybe_unused two = 2; +static int __maybe_unused three = 3; static unsigned long one_ul = 1; static int one_hundred = 100; #ifdef CONFIG_PRINTK @@ -168,8 +170,14 @@ static int proc_taint(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); #endif +#ifdef CONFIG_PRINTK +static int proc_dmesg_restrict(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos); +#endif + #ifdef CONFIG_MAGIC_SYSRQ -static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */ +/* Note: sysrq code uses it's own private copy */ +static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE; static int sysrq_sysctl_handler(ctl_table *table, int write, void __user *buffer, size_t *lenp, @@ -192,9 +200,9 @@ static int sysrq_sysctl_handler(ctl_table *table, int write, static struct ctl_table root_table[]; static struct ctl_table_root sysctl_table_root; static struct ctl_table_header root_table_header = { - .count = 1, + {{.count = 1, .ctl_table = root_table, - .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list), + .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}}, .root = &sysctl_table_root, .set = &sysctl_table_root.default_set, }; @@ -245,10 +253,6 @@ static struct ctl_table root_table[] = { .mode = 0555, .child = dev_table, }, -/* - * NOTE: do not add new entries to this table unless you have read - * Documentation/sysctl/ctl_unnumbered.txt - */ { } }; @@ -259,8 +263,6 @@ static int min_wakeup_granularity_ns; /* 0 usecs */ static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE; static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1; -static int min_sched_shares_ratelimit = 100000; /* 100 usec */ -static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */ #endif #ifdef CONFIG_COMPACTION @@ -305,15 +307,6 @@ static struct ctl_table kern_table[] = { .extra2 = &max_wakeup_granularity_ns, }, { - .procname = "sched_shares_ratelimit", - .data = &sysctl_sched_shares_ratelimit, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = sched_proc_update_handler, - .extra1 = &min_sched_shares_ratelimit, - .extra2 = &max_sched_shares_ratelimit, - }, - { .procname = "sched_tunable_scaling", .data = &sysctl_sched_tunable_scaling, .maxlen = sizeof(enum sched_tunable_scaling), @@ -323,14 +316,6 @@ static struct ctl_table kern_table[] = { .extra2 = &max_sched_tunable_scaling, }, { - .procname = "sched_shares_thresh", - .data = &sysctl_sched_shares_thresh, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &zero, - }, - { .procname = "sched_migration_cost", .data = &sysctl_sched_migration_cost, .maxlen = sizeof(unsigned int), @@ -352,6 +337,13 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, { + .procname = "sched_shares_window", + .data = &sysctl_sched_shares_window, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { .procname = "timer_migration", .data = &sysctl_timer_migration, .maxlen = sizeof(unsigned int), @@ -375,13 +367,17 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = sched_rt_handler, }, +#ifdef CONFIG_SCHED_AUTOGROUP { - .procname = "sched_compat_yield", - .data = &sysctl_sched_compat_yield, + .procname = "sched_autogroup_enabled", + .data = &sysctl_sched_autogroup_enabled, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, +#endif #ifdef CONFIG_PROVE_LOCKING { .procname = "prove_locking", @@ -702,6 +698,24 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &ten_thousand, }, + { + .procname = "dmesg_restrict", + .data = &dmesg_restrict, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, + { + .procname = "kptr_restrict", + .data = &kptr_restrict, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dmesg_restrict, + .extra1 = &zero, + .extra2 = &two, + }, #endif { .procname = "ngroups_max", @@ -716,14 +730,16 @@ static struct ctl_table kern_table[] = { .data = &watchdog_enabled, .maxlen = sizeof (int), .mode = 0644, - .proc_handler = proc_dowatchdog_enabled, + .proc_handler = proc_dowatchdog, + .extra1 = &zero, + .extra2 = &one, }, { .procname = "watchdog_thresh", - .data = &softlockup_thresh, + .data = &watchdog_thresh, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dowatchdog_thresh, + .proc_handler = proc_dowatchdog, .extra1 = &neg_one, .extra2 = &sixty, }, @@ -736,21 +752,23 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, -#endif -#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_LOCKUP_DETECTOR) { - .procname = "unknown_nmi_panic", - .data = &unknown_nmi_panic, + .procname = "nmi_watchdog", + .data = &watchdog_enabled, .maxlen = sizeof (int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dowatchdog, + .extra1 = &zero, + .extra2 = &one, }, +#endif +#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) { - .procname = "nmi_watchdog", - .data = &nmi_watchdog_enabled, + .procname = "unknown_nmi_panic", + .data = &unknown_nmi_panic, .maxlen = sizeof (int), .mode = 0644, - .proc_handler = proc_nmi_enabled, + .proc_handler = proc_dointvec, }, #endif #if defined(CONFIG_X86) @@ -933,7 +951,7 @@ static struct ctl_table kern_table[] = { .data = &sysctl_perf_event_sample_rate, .maxlen = sizeof(sysctl_perf_event_sample_rate), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = perf_proc_update_handler, }, #endif #ifdef CONFIG_KMEMCHECK @@ -954,10 +972,6 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, #endif -/* - * NOTE: do not add new entries to this table unless you have read - * Documentation/sysctl/ctl_unnumbered.txt - */ { } }; @@ -967,14 +981,18 @@ static struct ctl_table vm_table[] = { .data = &sysctl_overcommit_memory, .maxlen = sizeof(sysctl_overcommit_memory), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &two, }, { .procname = "panic_on_oom", .data = &sysctl_panic_on_oom, .maxlen = sizeof(sysctl_panic_on_oom), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &two, }, { .procname = "oom_kill_allocating_task", @@ -1002,7 +1020,8 @@ static struct ctl_table vm_table[] = { .data = &page_cluster, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, }, { .procname = "dirty_background_ratio", @@ -1050,7 +1069,8 @@ static struct ctl_table vm_table[] = { .data = &dirty_expire_interval, .maxlen = sizeof(dirty_expire_interval), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, }, { .procname = "nr_pdflush_threads", @@ -1126,6 +1146,8 @@ static struct ctl_table vm_table[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = drop_caches_sysctl_handler, + .extra1 = &one, + .extra2 = &three, }, #ifdef CONFIG_COMPACTION { @@ -1318,11 +1340,6 @@ static struct ctl_table vm_table[] = { .extra2 = &one, }, #endif - -/* - * NOTE: do not add new entries to this table unless you have read - * Documentation/sysctl/ctl_unnumbered.txt - */ { } }; @@ -1478,10 +1495,6 @@ static struct ctl_table fs_table[] = { .proc_handler = &pipe_proc_fn, .extra1 = &pipe_min_size, }, -/* - * NOTE: do not add new entries to this table unless you have read - * Documentation/sysctl/ctl_unnumbered.txt - */ { } }; @@ -1565,11 +1578,16 @@ void sysctl_head_get(struct ctl_table_header *head) spin_unlock(&sysctl_lock); } +static void free_head(struct rcu_head *rcu) +{ + kfree(container_of(rcu, struct ctl_table_header, rcu)); +} + void sysctl_head_put(struct ctl_table_header *head) { spin_lock(&sysctl_lock); if (!--head->count) - kfree(head); + call_rcu(&head->rcu, free_head); spin_unlock(&sysctl_lock); } @@ -1683,13 +1701,8 @@ static int test_perm(int mode, int op) int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op) { - int error; int mode; - error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC)); - if (error) - return error; - if (root->permissions) mode = root->permissions(root, current->nsproxy, table); else @@ -1946,10 +1959,10 @@ void unregister_sysctl_table(struct ctl_table_header * header) start_unregistering(header); if (!--header->parent->count) { WARN_ON(1); - kfree(header->parent); + call_rcu(&header->parent->rcu, free_head); } if (!--header->count) - kfree(header); + call_rcu(&header->rcu, free_head); spin_unlock(&sysctl_lock); } @@ -2390,6 +2403,17 @@ static int proc_taint(struct ctl_table *table, int write, return err; } +#ifdef CONFIG_PRINTK +static int proc_dmesg_restrict(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + return proc_dointvec_minmax(table, write, buffer, lenp, ppos); +} +#endif + struct do_proc_dointvec_minmax_conv_param { int *min; int *max; @@ -2891,7 +2915,7 @@ int proc_do_large_bitmap(struct ctl_table *table, int write, } } -#else /* CONFIG_PROC_FS */ +#else /* CONFIG_PROC_SYSCTL */ int proc_dostring(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) @@ -2943,7 +2967,7 @@ int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write, } -#endif /* CONFIG_PROC_FS */ +#endif /* CONFIG_PROC_SYSCTL */ /* * No sense putting this after each symbol definition, twice, diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 1357c578606..3b8e028b960 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -136,7 +136,6 @@ static const struct bin_table bin_kern_table[] = { { CTL_INT, KERN_IA64_UNALIGNED, "ignore-unaligned-usertrap" }, { CTL_INT, KERN_COMPAT_LOG, "compat-log" }, { CTL_INT, KERN_MAX_LOCK_DEPTH, "max_lock_depth" }, - { CTL_INT, KERN_NMI_WATCHDOG, "nmi_watchdog" }, { CTL_INT, KERN_PANIC_ON_NMI, "panic_on_unrecovered_nmi" }, {} }; @@ -1193,7 +1192,7 @@ static ssize_t bin_dn_node_address(struct file *file, buf[result] = '\0'; - /* Convert the decnet addresss to binary */ + /* Convert the decnet address to binary */ result = -EIO; nodep = strchr(buf, '.') + 1; if (!nodep) @@ -1322,13 +1321,11 @@ static ssize_t binary_sysctl(const int *name, int nlen, void __user *oldval, size_t oldlen, void __user *newval, size_t newlen) { const struct bin_table *table = NULL; - struct nameidata nd; struct vfsmount *mnt; struct file *file; ssize_t result; char *pathname; int flags; - int acc_mode; pathname = sysctl_getname(name, nlen, &table); result = PTR_ERR(pathname); @@ -1338,28 +1335,17 @@ static ssize_t binary_sysctl(const int *name, int nlen, /* How should the sysctl be accessed? */ if (oldval && oldlen && newval && newlen) { flags = O_RDWR; - acc_mode = MAY_READ | MAY_WRITE; } else if (newval && newlen) { flags = O_WRONLY; - acc_mode = MAY_WRITE; } else if (oldval && oldlen) { flags = O_RDONLY; - acc_mode = MAY_READ; } else { result = 0; goto out_putname; } mnt = current->nsproxy->pid_ns->proc_mnt; - result = vfs_path_lookup(mnt->mnt_root, mnt, pathname, 0, &nd); - if (result) - goto out_putname; - - result = may_open(&nd.path, acc_mode, flags); - if (result) - goto out_putpath; - - file = dentry_open(nd.path.dentry, nd.path.mnt, flags, current_cred()); + file = file_open_root(mnt->mnt_root, mnt, pathname, flags); result = PTR_ERR(file); if (IS_ERR(file)) goto out_putname; @@ -1371,10 +1357,6 @@ out_putname: putname(pathname); out: return result; - -out_putpath: - path_put(&nd.path); - goto out_putname; } diff --git a/kernel/sysctl_check.c b/kernel/sysctl_check.c index 10b90d8a03c..4e4932a7b36 100644 --- a/kernel/sysctl_check.c +++ b/kernel/sysctl_check.c @@ -111,11 +111,9 @@ int sysctl_check_table(struct nsproxy *namespaces, struct ctl_table *table) const char *fail = NULL; if (table->parent) { - if (table->procname && !table->parent->procname) + if (!table->parent->procname) set_fail(&fail, table, "Parent without procname"); } - if (!table->procname) - set_fail(&fail, table, "No procname"); if (table->child) { if (table->data) set_fail(&fail, table, "Directory with data?"); @@ -144,13 +142,9 @@ int sysctl_check_table(struct nsproxy *namespaces, struct ctl_table *table) set_fail(&fail, table, "No maxlen"); } #ifdef CONFIG_PROC_SYSCTL - if (table->procname && !table->proc_handler) + if (!table->proc_handler) set_fail(&fail, table, "No proc_handler"); #endif -#if 0 - if (!table->procname && table->proc_handler) - set_fail(&fail, table, "proc_handler without procname"); -#endif sysctl_check_leaf(namespaces, table, &fail); } if (table->mode > 0777) diff --git a/kernel/taskstats.c b/kernel/taskstats.c index c8231fb1570..9ffea360a77 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -89,8 +89,7 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, return -ENOMEM; if (!info) { - int seq = get_cpu_var(taskstats_seqnum)++; - put_cpu_var(taskstats_seqnum); + int seq = this_cpu_inc_return(taskstats_seqnum) - 1; reply = genlmsg_put(skb, 0, seq, &family, 0, cmd); } else @@ -349,25 +348,47 @@ static int parse(struct nlattr *na, struct cpumask *mask) return ret; } +#if defined(CONFIG_64BIT) && !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) +#define TASKSTATS_NEEDS_PADDING 1 +#endif + static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid) { struct nlattr *na, *ret; int aggr; - /* If we don't pad, we end up with alignment on a 4 byte boundary. - * This causes lots of runtime warnings on systems requiring 8 byte - * alignment */ - u32 pids[2] = { pid, 0 }; - int pid_size = ALIGN(sizeof(pid), sizeof(long)); - aggr = (type == TASKSTATS_TYPE_PID) ? TASKSTATS_TYPE_AGGR_PID : TASKSTATS_TYPE_AGGR_TGID; + /* + * The taskstats structure is internally aligned on 8 byte + * boundaries but the layout of the aggregrate reply, with + * two NLA headers and the pid (each 4 bytes), actually + * force the entire structure to be unaligned. This causes + * the kernel to issue unaligned access warnings on some + * architectures like ia64. Unfortunately, some software out there + * doesn't properly unroll the NLA packet and assumes that the start + * of the taskstats structure will always be 20 bytes from the start + * of the netlink payload. Aligning the start of the taskstats + * structure breaks this software, which we don't want. So, for now + * the alignment only happens on architectures that require it + * and those users will have to update to fixed versions of those + * packages. Space is reserved in the packet only when needed. + * This ifdef should be removed in several years e.g. 2012 once + * we can be confident that fixed versions are installed on most + * systems. We add the padding before the aggregate since the + * aggregate is already a defined type. + */ +#ifdef TASKSTATS_NEEDS_PADDING + if (nla_put(skb, TASKSTATS_TYPE_NULL, 0, NULL) < 0) + goto err; +#endif na = nla_nest_start(skb, aggr); if (!na) goto err; - if (nla_put(skb, type, pid_size, pids) < 0) + + if (nla_put(skb, type, sizeof(pid), &pid) < 0) goto err; ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats)); if (!ret) @@ -456,6 +477,18 @@ out: return rc; } +static size_t taskstats_packet_size(void) +{ + size_t size; + + size = nla_total_size(sizeof(u32)) + + nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); +#ifdef TASKSTATS_NEEDS_PADDING + size += nla_total_size(0); /* Padding for alignment */ +#endif + return size; +} + static int cmd_attr_pid(struct genl_info *info) { struct taskstats *stats; @@ -464,8 +497,7 @@ static int cmd_attr_pid(struct genl_info *info) u32 pid; int rc; - size = nla_total_size(sizeof(u32)) + - nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); + size = taskstats_packet_size(); rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); if (rc < 0) @@ -494,8 +526,7 @@ static int cmd_attr_tgid(struct genl_info *info) u32 tgid; int rc; - size = nla_total_size(sizeof(u32)) + - nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); + size = taskstats_packet_size(); rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size); if (rc < 0) @@ -570,8 +601,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead) /* * Size includes space for nested attributes */ - size = nla_total_size(sizeof(u32)) + - nla_total_size(sizeof(struct taskstats)) + nla_total_size(0); + size = taskstats_packet_size(); is_thread_group = !!taskstats_tgid_alloc(tsk); if (is_thread_group) { @@ -581,7 +611,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead) fill_tgid_exit(tsk); } - listeners = &__raw_get_cpu_var(listener_array); + listeners = __this_cpu_ptr(&listener_array); if (list_empty(&listeners->list)) return; @@ -655,7 +685,7 @@ static int __init taskstats_init(void) goto err_cgroup_ops; family_registered = 1; - printk("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); + pr_info("registered taskstats version %d\n", TASKSTATS_GENL_VERSION); return 0; err_cgroup_ops: genl_unregister_ops(&family, &taskstats_ops); diff --git a/kernel/time.c b/kernel/time.c index ba9b338d183..8e8dc6d705c 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -150,7 +150,7 @@ static inline void warp_clock(void) * various programs will get confused when the clock gets warped. */ -int do_sys_settimeofday(struct timespec *tv, struct timezone *tz) +int do_sys_settimeofday(const struct timespec *tv, const struct timezone *tz) { static int firsttime = 1; int error = 0; @@ -238,7 +238,7 @@ EXPORT_SYMBOL(current_fs_time); * Avoid unnecessary multiplications/divisions in the * two most common HZ cases: */ -unsigned int inline jiffies_to_msecs(const unsigned long j) +inline unsigned int jiffies_to_msecs(const unsigned long j) { #if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) return (MSEC_PER_SEC / HZ) * j; @@ -254,7 +254,7 @@ unsigned int inline jiffies_to_msecs(const unsigned long j) } EXPORT_SYMBOL(jiffies_to_msecs); -unsigned int inline jiffies_to_usecs(const unsigned long j) +inline unsigned int jiffies_to_usecs(const unsigned long j) { #if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) return (USEC_PER_SEC / HZ) * j; @@ -645,7 +645,7 @@ u64 nsec_to_clock_t(u64 x) } /** - * nsecs_to_jiffies - Convert nsecs in u64 to jiffies + * nsecs_to_jiffies64 - Convert nsecs in u64 to jiffies64 * * @n: nsecs in u64 * @@ -657,7 +657,7 @@ u64 nsec_to_clock_t(u64 x) * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years */ -unsigned long nsecs_to_jiffies(u64 n) +u64 nsecs_to_jiffies64(u64 n) { #if (NSEC_PER_SEC % HZ) == 0 /* Common case, HZ = 100, 128, 200, 250, 256, 500, 512, 1000 etc. */ @@ -674,22 +674,23 @@ unsigned long nsecs_to_jiffies(u64 n) #endif } -#if (BITS_PER_LONG < 64) -u64 get_jiffies_64(void) +/** + * nsecs_to_jiffies - Convert nsecs in u64 to jiffies + * + * @n: nsecs in u64 + * + * Unlike {m,u}secs_to_jiffies, type of input is not unsigned int but u64. + * And this doesn't return MAX_JIFFY_OFFSET since this function is designed + * for scheduler, not for use in device drivers to calculate timeout value. + * + * note: + * NSEC_PER_SEC = 10^9 = (5^9 * 2^9) = (1953125 * 512) + * ULLONG_MAX ns = 18446744073.709551615 secs = about 584 years + */ +unsigned long nsecs_to_jiffies(u64 n) { - unsigned long seq; - u64 ret; - - do { - seq = read_seqbegin(&xtime_lock); - ret = jiffies_64; - } while (read_seqretry(&xtime_lock, seq)); - return ret; + return (unsigned long)nsecs_to_jiffies64(n); } -EXPORT_SYMBOL(get_jiffies_64); -#endif - -EXPORT_SYMBOL(jiffies); /* * Add two timespec values and do a safety check for overflow. diff --git a/kernel/time/Makefile b/kernel/time/Makefile index ee266620b06..e2fd74b8e8c 100644 --- a/kernel/time/Makefile +++ b/kernel/time/Makefile @@ -1,4 +1,5 @@ -obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o timeconv.o +obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o +obj-y += timeconv.o posix-clock.o alarmtimer.o obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD) += clockevents.o obj-$(CONFIG_GENERIC_CLOCKEVENTS) += tick-common.o diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c new file mode 100644 index 00000000000..9265014cb4d --- /dev/null +++ b/kernel/time/alarmtimer.c @@ -0,0 +1,694 @@ +/* + * Alarmtimer interface + * + * This interface provides a timer which is similarto hrtimers, + * but triggers a RTC alarm if the box is suspend. + * + * This interface is influenced by the Android RTC Alarm timer + * interface. + * + * Copyright (C) 2010 IBM Corperation + * + * Author: John Stultz <john.stultz@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/time.h> +#include <linux/hrtimer.h> +#include <linux/timerqueue.h> +#include <linux/rtc.h> +#include <linux/alarmtimer.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> +#include <linux/posix-timers.h> +#include <linux/workqueue.h> +#include <linux/freezer.h> + +/** + * struct alarm_base - Alarm timer bases + * @lock: Lock for syncrhonized access to the base + * @timerqueue: Timerqueue head managing the list of events + * @timer: hrtimer used to schedule events while running + * @gettime: Function to read the time correlating to the base + * @base_clockid: clockid for the base + */ +static struct alarm_base { + spinlock_t lock; + struct timerqueue_head timerqueue; + struct hrtimer timer; + ktime_t (*gettime)(void); + clockid_t base_clockid; +} alarm_bases[ALARM_NUMTYPE]; + +#ifdef CONFIG_RTC_CLASS +/* rtc timer and device for setting alarm wakeups at suspend */ +static struct rtc_timer rtctimer; +static struct rtc_device *rtcdev; +#endif + +/* freezer delta & lock used to handle clock_nanosleep triggered wakeups */ +static ktime_t freezer_delta; +static DEFINE_SPINLOCK(freezer_delta_lock); + + +/** + * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue + * @base: pointer to the base where the timer is being run + * @alarm: pointer to alarm being enqueued. + * + * Adds alarm to a alarm_base timerqueue and if necessary sets + * an hrtimer to run. + * + * Must hold base->lock when calling. + */ +static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) +{ + timerqueue_add(&base->timerqueue, &alarm->node); + if (&alarm->node == timerqueue_getnext(&base->timerqueue)) { + hrtimer_try_to_cancel(&base->timer); + hrtimer_start(&base->timer, alarm->node.expires, + HRTIMER_MODE_ABS); + } +} + +/** + * alarmtimer_remove - Removes an alarm timer from an alarm_base timerqueue + * @base: pointer to the base where the timer is running + * @alarm: pointer to alarm being removed + * + * Removes alarm to a alarm_base timerqueue and if necessary sets + * a new timer to run. + * + * Must hold base->lock when calling. + */ +static void alarmtimer_remove(struct alarm_base *base, struct alarm *alarm) +{ + struct timerqueue_node *next = timerqueue_getnext(&base->timerqueue); + + timerqueue_del(&base->timerqueue, &alarm->node); + if (next == &alarm->node) { + hrtimer_try_to_cancel(&base->timer); + next = timerqueue_getnext(&base->timerqueue); + if (!next) + return; + hrtimer_start(&base->timer, next->expires, HRTIMER_MODE_ABS); + } +} + + +/** + * alarmtimer_fired - Handles alarm hrtimer being fired. + * @timer: pointer to hrtimer being run + * + * When a alarm timer fires, this runs through the timerqueue to + * see which alarms expired, and runs those. If there are more alarm + * timers queued for the future, we set the hrtimer to fire when + * when the next future alarm timer expires. + */ +static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) +{ + struct alarm_base *base = container_of(timer, struct alarm_base, timer); + struct timerqueue_node *next; + unsigned long flags; + ktime_t now; + int ret = HRTIMER_NORESTART; + + spin_lock_irqsave(&base->lock, flags); + now = base->gettime(); + while ((next = timerqueue_getnext(&base->timerqueue))) { + struct alarm *alarm; + ktime_t expired = next->expires; + + if (expired.tv64 >= now.tv64) + break; + + alarm = container_of(next, struct alarm, node); + + timerqueue_del(&base->timerqueue, &alarm->node); + alarm->enabled = 0; + /* Re-add periodic timers */ + if (alarm->period.tv64) { + alarm->node.expires = ktime_add(expired, alarm->period); + timerqueue_add(&base->timerqueue, &alarm->node); + alarm->enabled = 1; + } + spin_unlock_irqrestore(&base->lock, flags); + if (alarm->function) + alarm->function(alarm); + spin_lock_irqsave(&base->lock, flags); + } + + if (next) { + hrtimer_set_expires(&base->timer, next->expires); + ret = HRTIMER_RESTART; + } + spin_unlock_irqrestore(&base->lock, flags); + + return ret; + +} + +#ifdef CONFIG_RTC_CLASS +/** + * alarmtimer_suspend - Suspend time callback + * @dev: unused + * @state: unused + * + * When we are going into suspend, we look through the bases + * to see which is the soonest timer to expire. We then + * set an rtc timer to fire that far into the future, which + * will wake us from suspend. + */ +static int alarmtimer_suspend(struct device *dev) +{ + struct rtc_time tm; + ktime_t min, now; + unsigned long flags; + int i; + + spin_lock_irqsave(&freezer_delta_lock, flags); + min = freezer_delta; + freezer_delta = ktime_set(0, 0); + spin_unlock_irqrestore(&freezer_delta_lock, flags); + + /* If we have no rtcdev, just return */ + if (!rtcdev) + return 0; + + /* Find the soonest timer to expire*/ + for (i = 0; i < ALARM_NUMTYPE; i++) { + struct alarm_base *base = &alarm_bases[i]; + struct timerqueue_node *next; + ktime_t delta; + + spin_lock_irqsave(&base->lock, flags); + next = timerqueue_getnext(&base->timerqueue); + spin_unlock_irqrestore(&base->lock, flags); + if (!next) + continue; + delta = ktime_sub(next->expires, base->gettime()); + if (!min.tv64 || (delta.tv64 < min.tv64)) + min = delta; + } + if (min.tv64 == 0) + return 0; + + /* XXX - Should we enforce a minimum sleep time? */ + WARN_ON(min.tv64 < NSEC_PER_SEC); + + /* Setup an rtc timer to fire that far in the future */ + rtc_timer_cancel(rtcdev, &rtctimer); + rtc_read_time(rtcdev, &tm); + now = rtc_tm_to_ktime(tm); + now = ktime_add(now, min); + + rtc_timer_start(rtcdev, &rtctimer, now, ktime_set(0, 0)); + + return 0; +} +#else +static int alarmtimer_suspend(struct device *dev) +{ + return 0; +} +#endif + +static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) +{ + ktime_t delta; + unsigned long flags; + struct alarm_base *base = &alarm_bases[type]; + + delta = ktime_sub(absexp, base->gettime()); + + spin_lock_irqsave(&freezer_delta_lock, flags); + if (!freezer_delta.tv64 || (delta.tv64 < freezer_delta.tv64)) + freezer_delta = delta; + spin_unlock_irqrestore(&freezer_delta_lock, flags); +} + + +/** + * alarm_init - Initialize an alarm structure + * @alarm: ptr to alarm to be initialized + * @type: the type of the alarm + * @function: callback that is run when the alarm fires + */ +void alarm_init(struct alarm *alarm, enum alarmtimer_type type, + void (*function)(struct alarm *)) +{ + timerqueue_init(&alarm->node); + alarm->period = ktime_set(0, 0); + alarm->function = function; + alarm->type = type; + alarm->enabled = 0; +} + +/** + * alarm_start - Sets an alarm to fire + * @alarm: ptr to alarm to set + * @start: time to run the alarm + * @period: period at which the alarm will recur + */ +void alarm_start(struct alarm *alarm, ktime_t start, ktime_t period) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + unsigned long flags; + + spin_lock_irqsave(&base->lock, flags); + if (alarm->enabled) + alarmtimer_remove(base, alarm); + alarm->node.expires = start; + alarm->period = period; + alarmtimer_enqueue(base, alarm); + alarm->enabled = 1; + spin_unlock_irqrestore(&base->lock, flags); +} + +/** + * alarm_cancel - Tries to cancel an alarm timer + * @alarm: ptr to alarm to be canceled + */ +void alarm_cancel(struct alarm *alarm) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + unsigned long flags; + + spin_lock_irqsave(&base->lock, flags); + if (alarm->enabled) + alarmtimer_remove(base, alarm); + alarm->enabled = 0; + spin_unlock_irqrestore(&base->lock, flags); +} + + +/** + * clock2alarm - helper that converts from clockid to alarmtypes + * @clockid: clockid. + */ +static enum alarmtimer_type clock2alarm(clockid_t clockid) +{ + if (clockid == CLOCK_REALTIME_ALARM) + return ALARM_REALTIME; + if (clockid == CLOCK_BOOTTIME_ALARM) + return ALARM_BOOTTIME; + return -1; +} + +/** + * alarm_handle_timer - Callback for posix timers + * @alarm: alarm that fired + * + * Posix timer callback for expired alarm timers. + */ +static void alarm_handle_timer(struct alarm *alarm) +{ + struct k_itimer *ptr = container_of(alarm, struct k_itimer, + it.alarmtimer); + if (posix_timer_event(ptr, 0) != 0) + ptr->it_overrun++; +} + +/** + * alarm_clock_getres - posix getres interface + * @which_clock: clockid + * @tp: timespec to fill + * + * Returns the granularity of underlying alarm base clock + */ +static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp) +{ + clockid_t baseid = alarm_bases[clock2alarm(which_clock)].base_clockid; + + return hrtimer_get_res(baseid, tp); +} + +/** + * alarm_clock_get - posix clock_get interface + * @which_clock: clockid + * @tp: timespec to fill. + * + * Provides the underlying alarm base time. + */ +static int alarm_clock_get(clockid_t which_clock, struct timespec *tp) +{ + struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; + + *tp = ktime_to_timespec(base->gettime()); + return 0; +} + +/** + * alarm_timer_create - posix timer_create interface + * @new_timer: k_itimer pointer to manage + * + * Initializes the k_itimer structure. + */ +static int alarm_timer_create(struct k_itimer *new_timer) +{ + enum alarmtimer_type type; + struct alarm_base *base; + + if (!capable(CAP_WAKE_ALARM)) + return -EPERM; + + type = clock2alarm(new_timer->it_clock); + base = &alarm_bases[type]; + alarm_init(&new_timer->it.alarmtimer, type, alarm_handle_timer); + return 0; +} + +/** + * alarm_timer_get - posix timer_get interface + * @new_timer: k_itimer pointer + * @cur_setting: itimerspec data to fill + * + * Copies the itimerspec data out from the k_itimer + */ +static void alarm_timer_get(struct k_itimer *timr, + struct itimerspec *cur_setting) +{ + cur_setting->it_interval = + ktime_to_timespec(timr->it.alarmtimer.period); + cur_setting->it_value = + ktime_to_timespec(timr->it.alarmtimer.node.expires); + return; +} + +/** + * alarm_timer_del - posix timer_del interface + * @timr: k_itimer pointer to be deleted + * + * Cancels any programmed alarms for the given timer. + */ +static int alarm_timer_del(struct k_itimer *timr) +{ + alarm_cancel(&timr->it.alarmtimer); + return 0; +} + +/** + * alarm_timer_set - posix timer_set interface + * @timr: k_itimer pointer to be deleted + * @flags: timer flags + * @new_setting: itimerspec to be used + * @old_setting: itimerspec being replaced + * + * Sets the timer to new_setting, and starts the timer. + */ +static int alarm_timer_set(struct k_itimer *timr, int flags, + struct itimerspec *new_setting, + struct itimerspec *old_setting) +{ + /* Save old values */ + old_setting->it_interval = + ktime_to_timespec(timr->it.alarmtimer.period); + old_setting->it_value = + ktime_to_timespec(timr->it.alarmtimer.node.expires); + + /* If the timer was already set, cancel it */ + alarm_cancel(&timr->it.alarmtimer); + + /* start the timer */ + alarm_start(&timr->it.alarmtimer, + timespec_to_ktime(new_setting->it_value), + timespec_to_ktime(new_setting->it_interval)); + return 0; +} + +/** + * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep + * @alarm: ptr to alarm that fired + * + * Wakes up the task that set the alarmtimer + */ +static void alarmtimer_nsleep_wakeup(struct alarm *alarm) +{ + struct task_struct *task = (struct task_struct *)alarm->data; + + alarm->data = NULL; + if (task) + wake_up_process(task); +} + +/** + * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation + * @alarm: ptr to alarmtimer + * @absexp: absolute expiration time + * + * Sets the alarm timer and sleeps until it is fired or interrupted. + */ +static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp) +{ + alarm->data = (void *)current; + do { + set_current_state(TASK_INTERRUPTIBLE); + alarm_start(alarm, absexp, ktime_set(0, 0)); + if (likely(alarm->data)) + schedule(); + + alarm_cancel(alarm); + } while (alarm->data && !signal_pending(current)); + + __set_current_state(TASK_RUNNING); + + return (alarm->data == NULL); +} + + +/** + * update_rmtp - Update remaining timespec value + * @exp: expiration time + * @type: timer type + * @rmtp: user pointer to remaining timepsec value + * + * Helper function that fills in rmtp value with time between + * now and the exp value + */ +static int update_rmtp(ktime_t exp, enum alarmtimer_type type, + struct timespec __user *rmtp) +{ + struct timespec rmt; + ktime_t rem; + + rem = ktime_sub(exp, alarm_bases[type].gettime()); + + if (rem.tv64 <= 0) + return 0; + rmt = ktime_to_timespec(rem); + + if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) + return -EFAULT; + + return 1; + +} + +/** + * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep + * @restart: ptr to restart block + * + * Handles restarted clock_nanosleep calls + */ +static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) +{ + enum alarmtimer_type type = restart->nanosleep.index; + ktime_t exp; + struct timespec __user *rmtp; + struct alarm alarm; + int ret = 0; + + exp.tv64 = restart->nanosleep.expires; + alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); + + if (alarmtimer_do_nsleep(&alarm, exp)) + goto out; + + if (freezing(current)) + alarmtimer_freezerset(exp, type); + + rmtp = restart->nanosleep.rmtp; + if (rmtp) { + ret = update_rmtp(exp, type, rmtp); + if (ret <= 0) + goto out; + } + + + /* The other values in restart are already filled in */ + ret = -ERESTART_RESTARTBLOCK; +out: + return ret; +} + +/** + * alarm_timer_nsleep - alarmtimer nanosleep + * @which_clock: clockid + * @flags: determins abstime or relative + * @tsreq: requested sleep time (abs or rel) + * @rmtp: remaining sleep time saved + * + * Handles clock_nanosleep calls against _ALARM clockids + */ +static int alarm_timer_nsleep(const clockid_t which_clock, int flags, + struct timespec *tsreq, struct timespec __user *rmtp) +{ + enum alarmtimer_type type = clock2alarm(which_clock); + struct alarm alarm; + ktime_t exp; + int ret = 0; + struct restart_block *restart; + + if (!capable(CAP_WAKE_ALARM)) + return -EPERM; + + alarm_init(&alarm, type, alarmtimer_nsleep_wakeup); + + exp = timespec_to_ktime(*tsreq); + /* Convert (if necessary) to absolute time */ + if (flags != TIMER_ABSTIME) { + ktime_t now = alarm_bases[type].gettime(); + exp = ktime_add(now, exp); + } + + if (alarmtimer_do_nsleep(&alarm, exp)) + goto out; + + if (freezing(current)) + alarmtimer_freezerset(exp, type); + + /* abs timers don't set remaining time or restart */ + if (flags == TIMER_ABSTIME) { + ret = -ERESTARTNOHAND; + goto out; + } + + if (rmtp) { + ret = update_rmtp(exp, type, rmtp); + if (ret <= 0) + goto out; + } + + restart = ¤t_thread_info()->restart_block; + restart->fn = alarm_timer_nsleep_restart; + restart->nanosleep.index = type; + restart->nanosleep.expires = exp.tv64; + restart->nanosleep.rmtp = rmtp; + ret = -ERESTART_RESTARTBLOCK; + +out: + return ret; +} + + +/* Suspend hook structures */ +static const struct dev_pm_ops alarmtimer_pm_ops = { + .suspend = alarmtimer_suspend, +}; + +static struct platform_driver alarmtimer_driver = { + .driver = { + .name = "alarmtimer", + .pm = &alarmtimer_pm_ops, + } +}; + +/** + * alarmtimer_init - Initialize alarm timer code + * + * This function initializes the alarm bases and registers + * the posix clock ids. + */ +static int __init alarmtimer_init(void) +{ + int error = 0; + int i; + struct k_clock alarm_clock = { + .clock_getres = alarm_clock_getres, + .clock_get = alarm_clock_get, + .timer_create = alarm_timer_create, + .timer_set = alarm_timer_set, + .timer_del = alarm_timer_del, + .timer_get = alarm_timer_get, + .nsleep = alarm_timer_nsleep, + }; + + posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock); + posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock); + + /* Initialize alarm bases */ + alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; + alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; + alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; + alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; + for (i = 0; i < ALARM_NUMTYPE; i++) { + timerqueue_init_head(&alarm_bases[i].timerqueue); + spin_lock_init(&alarm_bases[i].lock); + hrtimer_init(&alarm_bases[i].timer, + alarm_bases[i].base_clockid, + HRTIMER_MODE_ABS); + alarm_bases[i].timer.function = alarmtimer_fired; + } + error = platform_driver_register(&alarmtimer_driver); + platform_device_register_simple("alarmtimer", -1, NULL, 0); + + return error; +} +device_initcall(alarmtimer_init); + +#ifdef CONFIG_RTC_CLASS +/** + * has_wakealarm - check rtc device has wakealarm ability + * @dev: current device + * @name_ptr: name to be returned + * + * This helper function checks to see if the rtc device can wake + * from suspend. + */ +static int __init has_wakealarm(struct device *dev, void *name_ptr) +{ + struct rtc_device *candidate = to_rtc_device(dev); + + if (!candidate->ops->set_alarm) + return 0; + if (!device_may_wakeup(candidate->dev.parent)) + return 0; + + *(const char **)name_ptr = dev_name(dev); + return 1; +} + +/** + * alarmtimer_init_late - Late initializing of alarmtimer code + * + * This function locates a rtc device to use for wakealarms. + * Run as late_initcall to make sure rtc devices have been + * registered. + */ +static int __init alarmtimer_init_late(void) +{ + char *str; + + /* Find an rtc device and init the rtc_timer */ + class_find_device(rtc_class, NULL, &str, has_wakealarm); + if (str) + rtcdev = rtc_class_open(str); + if (!rtcdev) { + printk(KERN_WARNING "No RTC device found, ALARM timers will" + " not wake from suspend"); + } + rtc_timer_init(&rtctimer, NULL, NULL); + + return 0; +} +#else +static int __init alarmtimer_init_late(void) +{ + printk(KERN_WARNING "Kernel not built with RTC support, ALARM timers" + " will not wake from suspend"); + return 0; +} +#endif +late_initcall(alarmtimer_init_late); diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index d7395fdfb9f..22a9da9a9c9 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -18,7 +18,6 @@ #include <linux/notifier.h> #include <linux/smp.h> #include <linux/sysdev.h> -#include <linux/tick.h> #include "tick-internal.h" @@ -195,6 +194,70 @@ void clockevents_register_device(struct clock_event_device *dev) } EXPORT_SYMBOL_GPL(clockevents_register_device); +static void clockevents_config(struct clock_event_device *dev, + u32 freq) +{ + unsigned long sec; + + if (!(dev->features & CLOCK_EVT_FEAT_ONESHOT)) + return; + + /* + * Calculate the maximum number of seconds we can sleep. Limit + * to 10 minutes for hardware which can program more than + * 32bit ticks so we still get reasonable conversion values. + */ + sec = dev->max_delta_ticks; + do_div(sec, freq); + if (!sec) + sec = 1; + else if (sec > 600 && dev->max_delta_ticks > UINT_MAX) + sec = 600; + + clockevents_calc_mult_shift(dev, freq, sec); + dev->min_delta_ns = clockevent_delta2ns(dev->min_delta_ticks, dev); + dev->max_delta_ns = clockevent_delta2ns(dev->max_delta_ticks, dev); +} + +/** + * clockevents_config_and_register - Configure and register a clock event device + * @dev: device to register + * @freq: The clock frequency + * @min_delta: The minimum clock ticks to program in oneshot mode + * @max_delta: The maximum clock ticks to program in oneshot mode + * + * min/max_delta can be 0 for devices which do not support oneshot mode. + */ +void clockevents_config_and_register(struct clock_event_device *dev, + u32 freq, unsigned long min_delta, + unsigned long max_delta) +{ + dev->min_delta_ticks = min_delta; + dev->max_delta_ticks = max_delta; + clockevents_config(dev, freq); + clockevents_register_device(dev); +} + +/** + * clockevents_update_freq - Update frequency and reprogram a clock event device. + * @dev: device to modify + * @freq: new device frequency + * + * Reconfigure and reprogram a clock event device in oneshot + * mode. Must be called on the cpu for which the device delivers per + * cpu timer events with interrupts disabled! Returns 0 on success, + * -ETIME when the event is in the past. + */ +int clockevents_update_freq(struct clock_event_device *dev, u32 freq) +{ + clockevents_config(dev, freq); + + if (dev->mode != CLOCK_EVT_MODE_ONESHOT) + return 0; + + return clockevents_program_event(dev, dev->next_event, ktime_get()); +} + /* * Noop handler when we shut down an event device */ diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index c18d7efa1b4..d9d5f8c885f 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -113,7 +113,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); * @shift: pointer to shift variable * @from: frequency to convert from * @to: frequency to convert to - * @minsec: guaranteed runtime conversion range in seconds + * @maxsec: guaranteed runtime conversion range in seconds * * The function evaluates the shift/mult pair for the scaled math * operations of clocksources and clockevents. @@ -122,7 +122,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); * NSEC_PER_SEC == 1GHz and @from is the counter frequency. For clock * event @to is the counter frequency and @from is NSEC_PER_SEC. * - * The @minsec conversion range argument controls the time frame in + * The @maxsec conversion range argument controls the time frame in * seconds which must be covered by the runtime conversion with the * calculated mult and shift factors. This guarantees that no 64bit * overflow happens when the input value of the conversion is @@ -131,7 +131,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time); * factors. */ void -clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec) +clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec) { u64 tmp; u32 sft, sftacc= 32; @@ -140,7 +140,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec) * Calculate the shift factor which is limiting the conversion * range: */ - tmp = ((u64)minsec * from) >> 32; + tmp = ((u64)maxsec * from) >> 32; while (tmp) { tmp >>=1; sftacc--; @@ -152,6 +152,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec) */ for (sft = 32; sft > 0; sft--) { tmp = (u64) to << sft; + tmp += from / 2; do_div(tmp, from); if ((tmp >> sftacc) == 0) break; @@ -625,19 +626,6 @@ static void clocksource_enqueue(struct clocksource *cs) list_add(&cs->list, entry); } - -/* - * Maximum time we expect to go between ticks. This includes idle - * tickless time. It provides the trade off between selecting a - * mult/shift pair that is very precise but can only handle a short - * period of time, vs. a mult/shift pair that can handle long periods - * of time but isn't as precise. - * - * This is a subsystem constant, and actual hardware limitations - * may override it (ie: clocksources that wrap every 3 seconds). - */ -#define MAX_UPDATE_LENGTH 5 /* Seconds */ - /** * __clocksource_updatefreq_scale - Used update clocksource with new freq * @t: clocksource to be registered @@ -651,15 +639,28 @@ static void clocksource_enqueue(struct clocksource *cs) */ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) { + unsigned long sec; + /* - * Ideally we want to use some of the limits used in - * clocksource_max_deferment, to provide a more informed - * MAX_UPDATE_LENGTH. But for now this just gets the - * register interface working properly. + * Calc the maximum number of seconds which we can run before + * wrapping around. For clocksources which have a mask > 32bit + * we need to limit the max sleep time to have a good + * conversion precision. 10 minutes is still a reasonable + * amount. That results in a shift value of 24 for a + * clocksource with mask >= 40bit and f >= 4GHz. That maps to + * ~ 0.06ppm granularity for NTP. We apply the same 12.5% + * margin as we do in clocksource_max_deferment() */ + sec = (cs->mask - (cs->mask >> 5)); + do_div(sec, freq); + do_div(sec, scale); + if (!sec) + sec = 1; + else if (sec > 600 && cs->mask > UINT_MAX) + sec = 600; + clocks_calc_mult_shift(&cs->mult, &cs->shift, freq, - NSEC_PER_SEC/scale, - MAX_UPDATE_LENGTH*scale); + NSEC_PER_SEC / scale, sec * scale); cs->max_idle_ns = clocksource_max_deferment(cs); } EXPORT_SYMBOL_GPL(__clocksource_updatefreq_scale); @@ -678,14 +679,14 @@ EXPORT_SYMBOL_GPL(__clocksource_updatefreq_scale); int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq) { - /* Intialize mult/shift and max_idle_ns */ + /* Initialize mult/shift and max_idle_ns */ __clocksource_updatefreq_scale(cs, scale, freq); /* Add clocksource to the clcoksource list */ mutex_lock(&clocksource_mutex); clocksource_enqueue(cs); - clocksource_select(); clocksource_enqueue_watchdog(cs); + clocksource_select(); mutex_unlock(&clocksource_mutex); return 0; } @@ -705,8 +706,8 @@ int clocksource_register(struct clocksource *cs) mutex_lock(&clocksource_mutex); clocksource_enqueue(cs); - clocksource_select(); clocksource_enqueue_watchdog(cs); + clocksource_select(); mutex_unlock(&clocksource_mutex); return 0; } diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index 5404a845690..a470154e040 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -22,8 +22,11 @@ ************************************************************************/ #include <linux/clocksource.h> #include <linux/jiffies.h> +#include <linux/module.h> #include <linux/init.h> +#include "tick-internal.h" + /* The Jiffies based clocksource is the lowest common * denominator clock source which should function on * all systems. It has the same coarse resolution as @@ -31,7 +34,7 @@ * inaccuracies caused by missed or lost timer * interrupts and the inability for the timer * interrupt hardware to accuratly tick at the - * requested HZ value. It is also not reccomended + * requested HZ value. It is also not recommended * for "tick-less" systems. */ #define NSEC_PER_JIFFY ((u32)((((u64)NSEC_PER_SEC)<<8)/ACTHZ)) @@ -64,6 +67,23 @@ struct clocksource clocksource_jiffies = { .shift = JIFFIES_SHIFT, }; +#if (BITS_PER_LONG < 64) +u64 get_jiffies_64(void) +{ + unsigned long seq; + u64 ret; + + do { + seq = read_seqbegin(&xtime_lock); + ret = jiffies_64; + } while (read_seqretry(&xtime_lock, seq)); + return ret; +} +EXPORT_SYMBOL(get_jiffies_64); +#endif + +EXPORT_SYMBOL(jiffies); + static int __init init_jiffies_clocksource(void) { return clocksource_register(&clocksource_jiffies); diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index d2321891538..f6117a4c7cb 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -14,6 +14,9 @@ #include <linux/timex.h> #include <linux/time.h> #include <linux/mm.h> +#include <linux/module.h> + +#include "tick-internal.h" /* * NTP timekeeping variables: @@ -74,6 +77,162 @@ static long time_adjust; /* constant (boot-param configurable) NTP tick adjustment (upscaled) */ static s64 ntp_tick_adj; +#ifdef CONFIG_NTP_PPS + +/* + * The following variables are used when a pulse-per-second (PPS) signal + * is available. They establish the engineering parameters of the clock + * discipline loop when controlled by the PPS signal. + */ +#define PPS_VALID 10 /* PPS signal watchdog max (s) */ +#define PPS_POPCORN 4 /* popcorn spike threshold (shift) */ +#define PPS_INTMIN 2 /* min freq interval (s) (shift) */ +#define PPS_INTMAX 8 /* max freq interval (s) (shift) */ +#define PPS_INTCOUNT 4 /* number of consecutive good intervals to + increase pps_shift or consecutive bad + intervals to decrease it */ +#define PPS_MAXWANDER 100000 /* max PPS freq wander (ns/s) */ + +static int pps_valid; /* signal watchdog counter */ +static long pps_tf[3]; /* phase median filter */ +static long pps_jitter; /* current jitter (ns) */ +static struct timespec pps_fbase; /* beginning of the last freq interval */ +static int pps_shift; /* current interval duration (s) (shift) */ +static int pps_intcnt; /* interval counter */ +static s64 pps_freq; /* frequency offset (scaled ns/s) */ +static long pps_stabil; /* current stability (scaled ns/s) */ + +/* + * PPS signal quality monitors + */ +static long pps_calcnt; /* calibration intervals */ +static long pps_jitcnt; /* jitter limit exceeded */ +static long pps_stbcnt; /* stability limit exceeded */ +static long pps_errcnt; /* calibration errors */ + + +/* PPS kernel consumer compensates the whole phase error immediately. + * Otherwise, reduce the offset by a fixed factor times the time constant. + */ +static inline s64 ntp_offset_chunk(s64 offset) +{ + if (time_status & STA_PPSTIME && time_status & STA_PPSSIGNAL) + return offset; + else + return shift_right(offset, SHIFT_PLL + time_constant); +} + +static inline void pps_reset_freq_interval(void) +{ + /* the PPS calibration interval may end + surprisingly early */ + pps_shift = PPS_INTMIN; + pps_intcnt = 0; +} + +/** + * pps_clear - Clears the PPS state variables + * + * Must be called while holding a write on the xtime_lock + */ +static inline void pps_clear(void) +{ + pps_reset_freq_interval(); + pps_tf[0] = 0; + pps_tf[1] = 0; + pps_tf[2] = 0; + pps_fbase.tv_sec = pps_fbase.tv_nsec = 0; + pps_freq = 0; +} + +/* Decrease pps_valid to indicate that another second has passed since + * the last PPS signal. When it reaches 0, indicate that PPS signal is + * missing. + * + * Must be called while holding a write on the xtime_lock + */ +static inline void pps_dec_valid(void) +{ + if (pps_valid > 0) + pps_valid--; + else { + time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER | + STA_PPSWANDER | STA_PPSERROR); + pps_clear(); + } +} + +static inline void pps_set_freq(s64 freq) +{ + pps_freq = freq; +} + +static inline int is_error_status(int status) +{ + return (time_status & (STA_UNSYNC|STA_CLOCKERR)) + /* PPS signal lost when either PPS time or + * PPS frequency synchronization requested + */ + || ((time_status & (STA_PPSFREQ|STA_PPSTIME)) + && !(time_status & STA_PPSSIGNAL)) + /* PPS jitter exceeded when + * PPS time synchronization requested */ + || ((time_status & (STA_PPSTIME|STA_PPSJITTER)) + == (STA_PPSTIME|STA_PPSJITTER)) + /* PPS wander exceeded or calibration error when + * PPS frequency synchronization requested + */ + || ((time_status & STA_PPSFREQ) + && (time_status & (STA_PPSWANDER|STA_PPSERROR))); +} + +static inline void pps_fill_timex(struct timex *txc) +{ + txc->ppsfreq = shift_right((pps_freq >> PPM_SCALE_INV_SHIFT) * + PPM_SCALE_INV, NTP_SCALE_SHIFT); + txc->jitter = pps_jitter; + if (!(time_status & STA_NANO)) + txc->jitter /= NSEC_PER_USEC; + txc->shift = pps_shift; + txc->stabil = pps_stabil; + txc->jitcnt = pps_jitcnt; + txc->calcnt = pps_calcnt; + txc->errcnt = pps_errcnt; + txc->stbcnt = pps_stbcnt; +} + +#else /* !CONFIG_NTP_PPS */ + +static inline s64 ntp_offset_chunk(s64 offset) +{ + return shift_right(offset, SHIFT_PLL + time_constant); +} + +static inline void pps_reset_freq_interval(void) {} +static inline void pps_clear(void) {} +static inline void pps_dec_valid(void) {} +static inline void pps_set_freq(s64 freq) {} + +static inline int is_error_status(int status) +{ + return status & (STA_UNSYNC|STA_CLOCKERR); +} + +static inline void pps_fill_timex(struct timex *txc) +{ + /* PPS is not implemented, so these are zero */ + txc->ppsfreq = 0; + txc->jitter = 0; + txc->shift = 0; + txc->stabil = 0; + txc->jitcnt = 0; + txc->calcnt = 0; + txc->errcnt = 0; + txc->stbcnt = 0; +} + +#endif /* CONFIG_NTP_PPS */ + /* * NTP methods: */ @@ -185,6 +344,9 @@ void ntp_clear(void) tick_length = tick_length_base; time_offset = 0; + + /* Clear PPS state variables */ + pps_clear(); } /* @@ -250,16 +412,16 @@ void second_overflow(void) time_status |= STA_UNSYNC; } - /* - * Compute the phase adjustment for the next second. The offset is - * reduced by a fixed factor times the time constant. - */ + /* Compute the phase adjustment for the next second */ tick_length = tick_length_base; - delta = shift_right(time_offset, SHIFT_PLL + time_constant); + delta = ntp_offset_chunk(time_offset); time_offset -= delta; tick_length += delta; + /* Check PPS signal */ + pps_dec_valid(); + if (!time_adjust) return; @@ -369,6 +531,8 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts) if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { time_state = TIME_OK; time_status = STA_UNSYNC; + /* restart PPS frequency calibration */ + pps_reset_freq_interval(); } /* @@ -418,6 +582,8 @@ static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts time_freq = txc->freq * PPM_SCALE; time_freq = min(time_freq, MAXFREQ_SCALED); time_freq = max(time_freq, -MAXFREQ_SCALED); + /* update pps_freq */ + pps_set_freq(time_freq); } if (txc->modes & ADJ_MAXERROR) @@ -482,6 +648,19 @@ int do_adjtimex(struct timex *txc) hrtimer_cancel(&leap_timer); } + if (txc->modes & ADJ_SETOFFSET) { + struct timespec delta; + delta.tv_sec = txc->time.tv_sec; + delta.tv_nsec = txc->time.tv_usec; + if (!capable(CAP_SYS_TIME)) + return -EPERM; + if (!(txc->modes & ADJ_NANO)) + delta.tv_nsec *= 1000; + result = timekeeping_inject_offset(&delta); + if (result) + return result; + } + getnstimeofday(&ts); write_seqlock_irq(&xtime_lock); @@ -508,7 +687,8 @@ int do_adjtimex(struct timex *txc) } result = time_state; /* mostly `TIME_OK' */ - if (time_status & (STA_UNSYNC|STA_CLOCKERR)) + /* check for errors */ + if (is_error_status(time_status)) result = TIME_ERROR; txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * @@ -522,15 +702,8 @@ int do_adjtimex(struct timex *txc) txc->tick = tick_usec; txc->tai = time_tai; - /* PPS is not implemented, so these are zero */ - txc->ppsfreq = 0; - txc->jitter = 0; - txc->shift = 0; - txc->stabil = 0; - txc->jitcnt = 0; - txc->calcnt = 0; - txc->errcnt = 0; - txc->stbcnt = 0; + /* fill PPS status fields */ + pps_fill_timex(txc); write_sequnlock_irq(&xtime_lock); @@ -544,6 +717,243 @@ int do_adjtimex(struct timex *txc) return result; } +#ifdef CONFIG_NTP_PPS + +/* actually struct pps_normtime is good old struct timespec, but it is + * semantically different (and it is the reason why it was invented): + * pps_normtime.nsec has a range of ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] + * while timespec.tv_nsec has a range of [0, NSEC_PER_SEC) */ +struct pps_normtime { + __kernel_time_t sec; /* seconds */ + long nsec; /* nanoseconds */ +}; + +/* normalize the timestamp so that nsec is in the + ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] interval */ +static inline struct pps_normtime pps_normalize_ts(struct timespec ts) +{ + struct pps_normtime norm = { + .sec = ts.tv_sec, + .nsec = ts.tv_nsec + }; + + if (norm.nsec > (NSEC_PER_SEC >> 1)) { + norm.nsec -= NSEC_PER_SEC; + norm.sec++; + } + + return norm; +} + +/* get current phase correction and jitter */ +static inline long pps_phase_filter_get(long *jitter) +{ + *jitter = pps_tf[0] - pps_tf[1]; + if (*jitter < 0) + *jitter = -*jitter; + + /* TODO: test various filters */ + return pps_tf[0]; +} + +/* add the sample to the phase filter */ +static inline void pps_phase_filter_add(long err) +{ + pps_tf[2] = pps_tf[1]; + pps_tf[1] = pps_tf[0]; + pps_tf[0] = err; +} + +/* decrease frequency calibration interval length. + * It is halved after four consecutive unstable intervals. + */ +static inline void pps_dec_freq_interval(void) +{ + if (--pps_intcnt <= -PPS_INTCOUNT) { + pps_intcnt = -PPS_INTCOUNT; + if (pps_shift > PPS_INTMIN) { + pps_shift--; + pps_intcnt = 0; + } + } +} + +/* increase frequency calibration interval length. + * It is doubled after four consecutive stable intervals. + */ +static inline void pps_inc_freq_interval(void) +{ + if (++pps_intcnt >= PPS_INTCOUNT) { + pps_intcnt = PPS_INTCOUNT; + if (pps_shift < PPS_INTMAX) { + pps_shift++; + pps_intcnt = 0; + } + } +} + +/* update clock frequency based on MONOTONIC_RAW clock PPS signal + * timestamps + * + * At the end of the calibration interval the difference between the + * first and last MONOTONIC_RAW clock timestamps divided by the length + * of the interval becomes the frequency update. If the interval was + * too long, the data are discarded. + * Returns the difference between old and new frequency values. + */ +static long hardpps_update_freq(struct pps_normtime freq_norm) +{ + long delta, delta_mod; + s64 ftemp; + + /* check if the frequency interval was too long */ + if (freq_norm.sec > (2 << pps_shift)) { + time_status |= STA_PPSERROR; + pps_errcnt++; + pps_dec_freq_interval(); + pr_err("hardpps: PPSERROR: interval too long - %ld s\n", + freq_norm.sec); + return 0; + } + + /* here the raw frequency offset and wander (stability) is + * calculated. If the wander is less than the wander threshold + * the interval is increased; otherwise it is decreased. + */ + ftemp = div_s64(((s64)(-freq_norm.nsec)) << NTP_SCALE_SHIFT, + freq_norm.sec); + delta = shift_right(ftemp - pps_freq, NTP_SCALE_SHIFT); + pps_freq = ftemp; + if (delta > PPS_MAXWANDER || delta < -PPS_MAXWANDER) { + pr_warning("hardpps: PPSWANDER: change=%ld\n", delta); + time_status |= STA_PPSWANDER; + pps_stbcnt++; + pps_dec_freq_interval(); + } else { /* good sample */ + pps_inc_freq_interval(); + } + + /* the stability metric is calculated as the average of recent + * frequency changes, but is used only for performance + * monitoring + */ + delta_mod = delta; + if (delta_mod < 0) + delta_mod = -delta_mod; + pps_stabil += (div_s64(((s64)delta_mod) << + (NTP_SCALE_SHIFT - SHIFT_USEC), + NSEC_PER_USEC) - pps_stabil) >> PPS_INTMIN; + + /* if enabled, the system clock frequency is updated */ + if ((time_status & STA_PPSFREQ) != 0 && + (time_status & STA_FREQHOLD) == 0) { + time_freq = pps_freq; + ntp_update_frequency(); + } + + return delta; +} + +/* correct REALTIME clock phase error against PPS signal */ +static void hardpps_update_phase(long error) +{ + long correction = -error; + long jitter; + + /* add the sample to the median filter */ + pps_phase_filter_add(correction); + correction = pps_phase_filter_get(&jitter); + + /* Nominal jitter is due to PPS signal noise. If it exceeds the + * threshold, the sample is discarded; otherwise, if so enabled, + * the time offset is updated. + */ + if (jitter > (pps_jitter << PPS_POPCORN)) { + pr_warning("hardpps: PPSJITTER: jitter=%ld, limit=%ld\n", + jitter, (pps_jitter << PPS_POPCORN)); + time_status |= STA_PPSJITTER; + pps_jitcnt++; + } else if (time_status & STA_PPSTIME) { + /* correct the time using the phase offset */ + time_offset = div_s64(((s64)correction) << NTP_SCALE_SHIFT, + NTP_INTERVAL_FREQ); + /* cancel running adjtime() */ + time_adjust = 0; + } + /* update jitter */ + pps_jitter += (jitter - pps_jitter) >> PPS_INTMIN; +} + +/* + * hardpps() - discipline CPU clock oscillator to external PPS signal + * + * This routine is called at each PPS signal arrival in order to + * discipline the CPU clock oscillator to the PPS signal. It takes two + * parameters: REALTIME and MONOTONIC_RAW clock timestamps. The former + * is used to correct clock phase error and the latter is used to + * correct the frequency. + * + * This code is based on David Mills's reference nanokernel + * implementation. It was mostly rewritten but keeps the same idea. + */ +void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) +{ + struct pps_normtime pts_norm, freq_norm; + unsigned long flags; + + pts_norm = pps_normalize_ts(*phase_ts); + + write_seqlock_irqsave(&xtime_lock, flags); + + /* clear the error bits, they will be set again if needed */ + time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR); + + /* indicate signal presence */ + time_status |= STA_PPSSIGNAL; + pps_valid = PPS_VALID; + + /* when called for the first time, + * just start the frequency interval */ + if (unlikely(pps_fbase.tv_sec == 0)) { + pps_fbase = *raw_ts; + write_sequnlock_irqrestore(&xtime_lock, flags); + return; + } + + /* ok, now we have a base for frequency calculation */ + freq_norm = pps_normalize_ts(timespec_sub(*raw_ts, pps_fbase)); + + /* check that the signal is in the range + * [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */ + if ((freq_norm.sec == 0) || + (freq_norm.nsec > MAXFREQ * freq_norm.sec) || + (freq_norm.nsec < -MAXFREQ * freq_norm.sec)) { + time_status |= STA_PPSJITTER; + /* restart the frequency calibration interval */ + pps_fbase = *raw_ts; + write_sequnlock_irqrestore(&xtime_lock, flags); + pr_err("hardpps: PPSJITTER: bad pulse\n"); + return; + } + + /* signal is ok */ + + /* check if the current frequency interval is finished */ + if (freq_norm.sec >= (1 << pps_shift)) { + pps_calcnt++; + /* restart the frequency calibration interval */ + pps_fbase = *raw_ts; + hardpps_update_freq(freq_norm); + } + + hardpps_update_phase(pts_norm.nsec); + + write_sequnlock_irqrestore(&xtime_lock, flags); +} +EXPORT_SYMBOL(hardpps); + +#endif /* CONFIG_NTP_PPS */ + static int __init ntp_tick_adj_setup(char *str) { ntp_tick_adj = simple_strtol(str, NULL, 0); diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c new file mode 100644 index 00000000000..c340ca658f3 --- /dev/null +++ b/kernel/time/posix-clock.c @@ -0,0 +1,445 @@ +/* + * posix-clock.c - support for dynamic clock devices + * + * Copyright (C) 2010 OMICRON electronics GmbH + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#include <linux/device.h> +#include <linux/file.h> +#include <linux/posix-clock.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/uaccess.h> + +static void delete_clock(struct kref *kref); + +/* + * Returns NULL if the posix_clock instance attached to 'fp' is old and stale. + */ +static struct posix_clock *get_posix_clock(struct file *fp) +{ + struct posix_clock *clk = fp->private_data; + + down_read(&clk->rwsem); + + if (!clk->zombie) + return clk; + + up_read(&clk->rwsem); + + return NULL; +} + +static void put_posix_clock(struct posix_clock *clk) +{ + up_read(&clk->rwsem); +} + +static ssize_t posix_clock_read(struct file *fp, char __user *buf, + size_t count, loff_t *ppos) +{ + struct posix_clock *clk = get_posix_clock(fp); + int err = -EINVAL; + + if (!clk) + return -ENODEV; + + if (clk->ops.read) + err = clk->ops.read(clk, fp->f_flags, buf, count); + + put_posix_clock(clk); + + return err; +} + +static unsigned int posix_clock_poll(struct file *fp, poll_table *wait) +{ + struct posix_clock *clk = get_posix_clock(fp); + int result = 0; + + if (!clk) + return -ENODEV; + + if (clk->ops.poll) + result = clk->ops.poll(clk, fp, wait); + + put_posix_clock(clk); + + return result; +} + +static int posix_clock_fasync(int fd, struct file *fp, int on) +{ + struct posix_clock *clk = get_posix_clock(fp); + int err = 0; + + if (!clk) + return -ENODEV; + + if (clk->ops.fasync) + err = clk->ops.fasync(clk, fd, fp, on); + + put_posix_clock(clk); + + return err; +} + +static int posix_clock_mmap(struct file *fp, struct vm_area_struct *vma) +{ + struct posix_clock *clk = get_posix_clock(fp); + int err = -ENODEV; + + if (!clk) + return -ENODEV; + + if (clk->ops.mmap) + err = clk->ops.mmap(clk, vma); + + put_posix_clock(clk); + + return err; +} + +static long posix_clock_ioctl(struct file *fp, + unsigned int cmd, unsigned long arg) +{ + struct posix_clock *clk = get_posix_clock(fp); + int err = -ENOTTY; + + if (!clk) + return -ENODEV; + + if (clk->ops.ioctl) + err = clk->ops.ioctl(clk, cmd, arg); + + put_posix_clock(clk); + + return err; +} + +#ifdef CONFIG_COMPAT +static long posix_clock_compat_ioctl(struct file *fp, + unsigned int cmd, unsigned long arg) +{ + struct posix_clock *clk = get_posix_clock(fp); + int err = -ENOTTY; + + if (!clk) + return -ENODEV; + + if (clk->ops.ioctl) + err = clk->ops.ioctl(clk, cmd, arg); + + put_posix_clock(clk); + + return err; +} +#endif + +static int posix_clock_open(struct inode *inode, struct file *fp) +{ + int err; + struct posix_clock *clk = + container_of(inode->i_cdev, struct posix_clock, cdev); + + down_read(&clk->rwsem); + + if (clk->zombie) { + err = -ENODEV; + goto out; + } + if (clk->ops.open) + err = clk->ops.open(clk, fp->f_mode); + else + err = 0; + + if (!err) { + kref_get(&clk->kref); + fp->private_data = clk; + } +out: + up_read(&clk->rwsem); + return err; +} + +static int posix_clock_release(struct inode *inode, struct file *fp) +{ + struct posix_clock *clk = fp->private_data; + int err = 0; + + if (clk->ops.release) + err = clk->ops.release(clk); + + kref_put(&clk->kref, delete_clock); + + fp->private_data = NULL; + + return err; +} + +static const struct file_operations posix_clock_file_operations = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = posix_clock_read, + .poll = posix_clock_poll, + .unlocked_ioctl = posix_clock_ioctl, + .open = posix_clock_open, + .release = posix_clock_release, + .fasync = posix_clock_fasync, + .mmap = posix_clock_mmap, +#ifdef CONFIG_COMPAT + .compat_ioctl = posix_clock_compat_ioctl, +#endif +}; + +int posix_clock_register(struct posix_clock *clk, dev_t devid) +{ + int err; + + kref_init(&clk->kref); + init_rwsem(&clk->rwsem); + + cdev_init(&clk->cdev, &posix_clock_file_operations); + clk->cdev.owner = clk->ops.owner; + err = cdev_add(&clk->cdev, devid, 1); + + return err; +} +EXPORT_SYMBOL_GPL(posix_clock_register); + +static void delete_clock(struct kref *kref) +{ + struct posix_clock *clk = container_of(kref, struct posix_clock, kref); + + if (clk->release) + clk->release(clk); +} + +void posix_clock_unregister(struct posix_clock *clk) +{ + cdev_del(&clk->cdev); + + down_write(&clk->rwsem); + clk->zombie = true; + up_write(&clk->rwsem); + + kref_put(&clk->kref, delete_clock); +} +EXPORT_SYMBOL_GPL(posix_clock_unregister); + +struct posix_clock_desc { + struct file *fp; + struct posix_clock *clk; +}; + +static int get_clock_desc(const clockid_t id, struct posix_clock_desc *cd) +{ + struct file *fp = fget(CLOCKID_TO_FD(id)); + int err = -EINVAL; + + if (!fp) + return err; + + if (fp->f_op->open != posix_clock_open || !fp->private_data) + goto out; + + cd->fp = fp; + cd->clk = get_posix_clock(fp); + + err = cd->clk ? 0 : -ENODEV; +out: + if (err) + fput(fp); + return err; +} + +static void put_clock_desc(struct posix_clock_desc *cd) +{ + put_posix_clock(cd->clk); + fput(cd->fp); +} + +static int pc_clock_adjtime(clockid_t id, struct timex *tx) +{ + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if ((cd.fp->f_mode & FMODE_WRITE) == 0) { + err = -EACCES; + goto out; + } + + if (cd.clk->ops.clock_adjtime) + err = cd.clk->ops.clock_adjtime(cd.clk, tx); + else + err = -EOPNOTSUPP; +out: + put_clock_desc(&cd); + + return err; +} + +static int pc_clock_gettime(clockid_t id, struct timespec *ts) +{ + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if (cd.clk->ops.clock_gettime) + err = cd.clk->ops.clock_gettime(cd.clk, ts); + else + err = -EOPNOTSUPP; + + put_clock_desc(&cd); + + return err; +} + +static int pc_clock_getres(clockid_t id, struct timespec *ts) +{ + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if (cd.clk->ops.clock_getres) + err = cd.clk->ops.clock_getres(cd.clk, ts); + else + err = -EOPNOTSUPP; + + put_clock_desc(&cd); + + return err; +} + +static int pc_clock_settime(clockid_t id, const struct timespec *ts) +{ + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if ((cd.fp->f_mode & FMODE_WRITE) == 0) { + err = -EACCES; + goto out; + } + + if (cd.clk->ops.clock_settime) + err = cd.clk->ops.clock_settime(cd.clk, ts); + else + err = -EOPNOTSUPP; +out: + put_clock_desc(&cd); + + return err; +} + +static int pc_timer_create(struct k_itimer *kit) +{ + clockid_t id = kit->it_clock; + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if (cd.clk->ops.timer_create) + err = cd.clk->ops.timer_create(cd.clk, kit); + else + err = -EOPNOTSUPP; + + put_clock_desc(&cd); + + return err; +} + +static int pc_timer_delete(struct k_itimer *kit) +{ + clockid_t id = kit->it_clock; + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if (cd.clk->ops.timer_delete) + err = cd.clk->ops.timer_delete(cd.clk, kit); + else + err = -EOPNOTSUPP; + + put_clock_desc(&cd); + + return err; +} + +static void pc_timer_gettime(struct k_itimer *kit, struct itimerspec *ts) +{ + clockid_t id = kit->it_clock; + struct posix_clock_desc cd; + + if (get_clock_desc(id, &cd)) + return; + + if (cd.clk->ops.timer_gettime) + cd.clk->ops.timer_gettime(cd.clk, kit, ts); + + put_clock_desc(&cd); +} + +static int pc_timer_settime(struct k_itimer *kit, int flags, + struct itimerspec *ts, struct itimerspec *old) +{ + clockid_t id = kit->it_clock; + struct posix_clock_desc cd; + int err; + + err = get_clock_desc(id, &cd); + if (err) + return err; + + if (cd.clk->ops.timer_settime) + err = cd.clk->ops.timer_settime(cd.clk, kit, flags, ts, old); + else + err = -EOPNOTSUPP; + + put_clock_desc(&cd); + + return err; +} + +struct k_clock clock_posix_dynamic = { + .clock_getres = pc_clock_getres, + .clock_set = pc_clock_settime, + .clock_get = pc_clock_gettime, + .clock_adj = pc_clock_adjtime, + .timer_create = pc_timer_create, + .timer_set = pc_timer_settime, + .timer_del = pc_timer_delete, + .timer_get = pc_timer_gettime, +}; diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 48b2761b566..723c7637e55 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -18,7 +18,6 @@ #include <linux/percpu.h> #include <linux/profile.h> #include <linux/sched.h> -#include <linux/tick.h> #include "tick-internal.h" @@ -523,10 +522,11 @@ static void tick_broadcast_init_next_event(struct cpumask *mask, */ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { + int cpu = smp_processor_id(); + /* Set it up only once ! */ if (bc->event_handler != tick_handle_oneshot_broadcast) { int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC; - int cpu = smp_processor_id(); bc->event_handler = tick_handle_oneshot_broadcast; clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); @@ -552,6 +552,15 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) tick_broadcast_set_event(tick_next_period, 1); } else bc->next_event.tv64 = KTIME_MAX; + } else { + /* + * The first cpu which switches to oneshot mode sets + * the bit for all other cpus which are in the general + * (periodic) broadcast mask. So the bit is set and + * would prevent the first broadcast enter after this + * to program the bc device. + */ + tick_broadcast_clear_oneshot(cpu); } } @@ -600,4 +609,14 @@ int tick_broadcast_oneshot_active(void) return tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT; } +/* + * Check whether the broadcast device supports oneshot. + */ +bool tick_broadcast_oneshot_available(void) +{ + struct clock_event_device *bc = tick_broadcast_device.evtdev; + + return bc ? bc->features & CLOCK_EVT_FEAT_ONESHOT : false; +} + #endif diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index b6b898d2eee..119528de823 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -18,7 +18,6 @@ #include <linux/percpu.h> #include <linux/profile.h> #include <linux/sched.h> -#include <linux/tick.h> #include <asm/irq_regs.h> @@ -49,9 +48,13 @@ struct tick_device *tick_get_device(int cpu) */ int tick_is_oneshot_available(void) { - struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; + struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev); - return dev && (dev->features & CLOCK_EVT_FEAT_ONESHOT); + if (!dev || !(dev->features & CLOCK_EVT_FEAT_ONESHOT)) + return 0; + if (!(dev->features & CLOCK_EVT_FEAT_C3STOP)) + return 1; + return tick_broadcast_oneshot_available(); } /* diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 290eefbc1f6..1009b06d6f8 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -1,6 +1,10 @@ /* * tick internal variable and functions used by low/high res code */ +#include <linux/hrtimer.h> +#include <linux/tick.h> + +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD #define TICK_DO_TIMER_NONE -1 #define TICK_DO_TIMER_BOOT -2 @@ -36,6 +40,7 @@ extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup); extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc); extern int tick_broadcast_oneshot_active(void); extern void tick_check_oneshot_broadcast(int cpu); +bool tick_broadcast_oneshot_available(void); # else /* BROADCAST */ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { @@ -46,6 +51,7 @@ static inline void tick_broadcast_switch_to_oneshot(void) { } static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { } static inline int tick_broadcast_oneshot_active(void) { return 0; } static inline void tick_check_oneshot_broadcast(int cpu) { } +static inline bool tick_broadcast_oneshot_available(void) { return true; } # endif /* !BROADCAST */ #else /* !ONESHOT */ @@ -76,6 +82,7 @@ static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc) return 0; } static inline int tick_broadcast_oneshot_active(void) { return 0; } +static inline bool tick_broadcast_oneshot_available(void) { return false; } #endif /* !TICK_ONESHOT */ /* @@ -132,3 +139,8 @@ static inline int tick_device_is_functional(struct clock_event_device *dev) { return !(dev->features & CLOCK_EVT_FEAT_DUMMY); } + +#endif + +extern void do_timer(unsigned long ticks); +extern seqlock_t xtime_lock; diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index aada0e52680..2d04411a5f0 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -18,7 +18,6 @@ #include <linux/percpu.h> #include <linux/profile.h> #include <linux/sched.h> -#include <linux/tick.h> #include "tick-internal.h" @@ -95,7 +94,7 @@ int tick_dev_program_event(struct clock_event_device *dev, ktime_t expires, */ int tick_program_event(ktime_t expires, int force) { - struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; + struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev); return tick_dev_program_event(dev, expires, force); } @@ -167,7 +166,7 @@ int tick_oneshot_mode_active(void) int ret; local_irq_save(flags); - ret = __get_cpu_var(tick_cpu_device).mode == TICKDEV_MODE_ONESHOT; + ret = __this_cpu_read(tick_cpu_device.mode) == TICKDEV_MODE_ONESHOT; local_irq_restore(flags); return ret; diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 3e216e01bbd..d5097c44b40 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -19,7 +19,6 @@ #include <linux/percpu.h> #include <linux/profile.h> #include <linux/sched.h> -#include <linux/tick.h> #include <linux/module.h> #include <asm/irq_regs.h> @@ -642,8 +641,7 @@ static void tick_nohz_switch_to_nohz(void) } local_irq_enable(); - printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", - smp_processor_id()); + printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", smp_processor_id()); } /* @@ -795,8 +793,10 @@ void tick_setup_sched_timer(void) } #ifdef CONFIG_NO_HZ - if (tick_nohz_enabled) + if (tick_nohz_enabled) { ts->nohz_mode = NOHZ_MODE_HIGHRES; + printk(KERN_INFO "Switched to NOHz mode on CPU #%d\n", smp_processor_id()); + } #endif } #endif /* HIGH_RES_TIMERS */ diff --git a/kernel/time/timecompare.c b/kernel/time/timecompare.c index ac38fbb176c..a9ae369925c 100644 --- a/kernel/time/timecompare.c +++ b/kernel/time/timecompare.c @@ -21,6 +21,7 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/math64.h> +#include <linux/kernel.h> /* * fixed point arithmetic scale factor for skew @@ -57,11 +58,11 @@ int timecompare_offset(struct timecompare *sync, int index; int num_samples = sync->num_samples; - if (num_samples > sizeof(buffer)/sizeof(buffer[0])) { + if (num_samples > ARRAY_SIZE(buffer)) { samples = kmalloc(sizeof(*samples) * num_samples, GFP_ATOMIC); if (!samples) { samples = buffer; - num_samples = sizeof(buffer)/sizeof(buffer[0]); + num_samples = ARRAY_SIZE(buffer); } } else { samples = buffer; diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 49010d822f7..8e6a05a5915 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -14,7 +14,7 @@ #include <linux/init.h> #include <linux/mm.h> #include <linux/sched.h> -#include <linux/sysdev.h> +#include <linux/syscore_ops.h> #include <linux/clocksource.h> #include <linux/jiffies.h> #include <linux/time.h> @@ -32,6 +32,8 @@ struct timekeeper { cycle_t cycle_interval; /* Number of clock shifted nano seconds in one NTP interval. */ u64 xtime_interval; + /* shifted nano seconds left over when rounding cycle_interval */ + s64 xtime_remainder; /* Raw nano seconds accumulated per NTP interval. */ u32 raw_interval; @@ -47,7 +49,7 @@ struct timekeeper { u32 mult; }; -struct timekeeper timekeeper; +static struct timekeeper timekeeper; /** * timekeeper_setup_internals - Set up internals to use clocksource clock. @@ -62,7 +64,7 @@ struct timekeeper timekeeper; static void timekeeper_setup_internals(struct clocksource *clock) { cycle_t interval; - u64 tmp; + u64 tmp, ntpinterval; timekeeper.clock = clock; clock->cycle_last = clock->read(clock); @@ -70,6 +72,7 @@ static void timekeeper_setup_internals(struct clocksource *clock) /* Do the ns -> cycle conversion first, using original mult */ tmp = NTP_INTERVAL_LENGTH; tmp <<= clock->shift; + ntpinterval = tmp; tmp += clock->mult/2; do_div(tmp, clock->mult); if (tmp == 0) @@ -80,6 +83,7 @@ static void timekeeper_setup_internals(struct clocksource *clock) /* Go back from cycles -> shifted ns */ timekeeper.xtime_interval = (u64) interval * clock->mult; + timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval; timekeeper.raw_interval = ((u64) interval * clock->mult) >> clock->shift; @@ -160,7 +164,7 @@ static struct timespec total_sleep_time; /* * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */ -struct timespec raw_time; +static struct timespec raw_time; /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; @@ -284,6 +288,49 @@ void ktime_get_ts(struct timespec *ts) } EXPORT_SYMBOL_GPL(ktime_get_ts); +#ifdef CONFIG_NTP_PPS + +/** + * getnstime_raw_and_real - get day and raw monotonic time in timespec format + * @ts_raw: pointer to the timespec to be set to raw monotonic time + * @ts_real: pointer to the timespec to be set to the time of day + * + * This function reads both the time of day and raw monotonic time at the + * same time atomically and stores the resulting timestamps in timespec + * format. + */ +void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) +{ + unsigned long seq; + s64 nsecs_raw, nsecs_real; + + WARN_ON_ONCE(timekeeping_suspended); + + do { + u32 arch_offset; + + seq = read_seqbegin(&xtime_lock); + + *ts_raw = raw_time; + *ts_real = xtime; + + nsecs_raw = timekeeping_get_ns_raw(); + nsecs_real = timekeeping_get_ns(); + + /* If arch requires, add in gettimeoffset() */ + arch_offset = arch_gettimeoffset(); + nsecs_raw += arch_offset; + nsecs_real += arch_offset; + + } while (read_seqretry(&xtime_lock, seq)); + + timespec_add_ns(ts_raw, nsecs_raw); + timespec_add_ns(ts_real, nsecs_real); +} +EXPORT_SYMBOL(getnstime_raw_and_real); + +#endif /* CONFIG_NTP_PPS */ + /** * do_gettimeofday - Returns the time of day in a timeval * @tv: pointer to the timeval to be set @@ -306,7 +353,7 @@ EXPORT_SYMBOL(do_gettimeofday); * * Sets the time of day to the new time and update NTP and notify hrtimers */ -int do_settimeofday(struct timespec *tv) +int do_settimeofday(const struct timespec *tv) { struct timespec ts_delta; unsigned long flags; @@ -340,6 +387,42 @@ int do_settimeofday(struct timespec *tv) EXPORT_SYMBOL(do_settimeofday); + +/** + * timekeeping_inject_offset - Adds or subtracts from the current time. + * @tv: pointer to the timespec variable containing the offset + * + * Adds or subtracts an offset value from the current time. + */ +int timekeeping_inject_offset(struct timespec *ts) +{ + unsigned long flags; + + if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) + return -EINVAL; + + write_seqlock_irqsave(&xtime_lock, flags); + + timekeeping_forward_now(); + + xtime = timespec_add(xtime, *ts); + wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts); + + timekeeper.ntp_error = 0; + ntp_clear(); + + update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, + timekeeper.mult); + + write_sequnlock_irqrestore(&xtime_lock, flags); + + /* signal hrtimers about time change */ + clock_was_set(); + + return 0; +} +EXPORT_SYMBOL(timekeeping_inject_offset); + /** * change_clocksource - Swaps clocksources if a new one is available * @@ -513,14 +596,65 @@ void __init timekeeping_init(void) static struct timespec timekeeping_suspend_time; /** + * __timekeeping_inject_sleeptime - Internal function to add sleep interval + * @delta: pointer to a timespec delta value + * + * Takes a timespec offset measuring a suspend interval and properly + * adds the sleep offset to the timekeeping variables. + */ +static void __timekeeping_inject_sleeptime(struct timespec *delta) +{ + xtime = timespec_add(xtime, *delta); + wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta); + total_sleep_time = timespec_add(total_sleep_time, *delta); +} + + +/** + * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values + * @delta: pointer to a timespec delta value + * + * This hook is for architectures that cannot support read_persistent_clock + * because their RTC/persistent clock is only accessible when irqs are enabled. + * + * This function should only be called by rtc_resume(), and allows + * a suspend offset to be injected into the timekeeping values. + */ +void timekeeping_inject_sleeptime(struct timespec *delta) +{ + unsigned long flags; + struct timespec ts; + + /* Make sure we don't set the clock twice */ + read_persistent_clock(&ts); + if (!(ts.tv_sec == 0 && ts.tv_nsec == 0)) + return; + + write_seqlock_irqsave(&xtime_lock, flags); + timekeeping_forward_now(); + + __timekeeping_inject_sleeptime(delta); + + timekeeper.ntp_error = 0; + ntp_clear(); + update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock, + timekeeper.mult); + + write_sequnlock_irqrestore(&xtime_lock, flags); + + /* signal hrtimers about time change */ + clock_was_set(); +} + + +/** * timekeeping_resume - Resumes the generic timekeeping subsystem. - * @dev: unused * * This is for the generic clocksource timekeeping. * xtime/wall_to_monotonic/jiffies/etc are * still managed by arch specific suspend/resume code. */ -static int timekeeping_resume(struct sys_device *dev) +static void timekeeping_resume(void) { unsigned long flags; struct timespec ts; @@ -533,9 +667,7 @@ static int timekeeping_resume(struct sys_device *dev) if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { ts = timespec_sub(ts, timekeeping_suspend_time); - xtime = timespec_add(xtime, ts); - wall_to_monotonic = timespec_sub(wall_to_monotonic, ts); - total_sleep_time = timespec_add(total_sleep_time, ts); + __timekeeping_inject_sleeptime(&ts); } /* re-base the last cycle value */ timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); @@ -549,11 +681,9 @@ static int timekeeping_resume(struct sys_device *dev) /* Resume hrtimers */ hres_timers_resume(); - - return 0; } -static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) +static int timekeeping_suspend(void) { unsigned long flags; @@ -571,26 +701,18 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) } /* sysfs resume/suspend bits for timekeeping */ -static struct sysdev_class timekeeping_sysclass = { - .name = "timekeeping", +static struct syscore_ops timekeeping_syscore_ops = { .resume = timekeeping_resume, .suspend = timekeeping_suspend, }; -static struct sys_device device_timer = { - .id = 0, - .cls = &timekeeping_sysclass, -}; - -static int __init timekeeping_init_device(void) +static int __init timekeeping_init_ops(void) { - int error = sysdev_class_register(&timekeeping_sysclass); - if (!error) - error = sysdev_register(&device_timer); - return error; + register_syscore_ops(&timekeeping_syscore_ops); + return 0; } -device_initcall(timekeeping_init_device); +device_initcall(timekeeping_init_ops); /* * If the error is already larger, we look ahead even further @@ -719,7 +841,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) /* Accumulate error between NTP and clock interval */ timekeeper.ntp_error += tick_length << shift; - timekeeper.ntp_error -= timekeeper.xtime_interval << + timekeeper.ntp_error -= + (timekeeper.xtime_interval + timekeeper.xtime_remainder) << (timekeeper.ntp_error_shift + shift); return offset; @@ -731,7 +854,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) * * Called from the timer interrupt, must hold a write on xtime_lock. */ -void update_wall_time(void) +static void update_wall_time(void) { struct clocksource *clock; cycle_t offset; @@ -823,7 +946,7 @@ void update_wall_time(void) * getboottime - Return the real time of system boot. * @ts: pointer to the timespec to be set * - * Returns the time of day in a timespec. + * Returns the wall-time of boot in a timespec. * * This is based on the wall_to_monotonic offset and the total suspend * time. Calls to settimeofday will affect the value returned (which @@ -841,6 +964,55 @@ void getboottime(struct timespec *ts) } EXPORT_SYMBOL_GPL(getboottime); + +/** + * get_monotonic_boottime - Returns monotonic time since boot + * @ts: pointer to the timespec to be set + * + * Returns the monotonic time since boot in a timespec. + * + * This is similar to CLOCK_MONTONIC/ktime_get_ts, but also + * includes the time spent in suspend. + */ +void get_monotonic_boottime(struct timespec *ts) +{ + struct timespec tomono, sleep; + unsigned int seq; + s64 nsecs; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqbegin(&xtime_lock); + *ts = xtime; + tomono = wall_to_monotonic; + sleep = total_sleep_time; + nsecs = timekeeping_get_ns(); + + } while (read_seqretry(&xtime_lock, seq)); + + set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec, + ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec + nsecs); +} +EXPORT_SYMBOL_GPL(get_monotonic_boottime); + +/** + * ktime_get_boottime - Returns monotonic time since boot in a ktime + * + * Returns the monotonic time since boot in a ktime + * + * This is similar to CLOCK_MONTONIC/ktime_get, but also + * includes the time spent in suspend. + */ +ktime_t ktime_get_boottime(void) +{ + struct timespec ts; + + get_monotonic_boottime(&ts); + return timespec_to_ktime(ts); +} +EXPORT_SYMBOL_GPL(ktime_get_boottime); + /** * monotonic_to_bootbased - Convert the monotonic time to boot based. * @ts: pointer to the timespec to be converted @@ -862,11 +1034,6 @@ struct timespec __current_kernel_time(void) return xtime; } -struct timespec __get_wall_to_monotonic(void) -{ - return wall_to_monotonic; -} - struct timespec current_kernel_time(void) { struct timespec now; @@ -898,3 +1065,48 @@ struct timespec get_monotonic_coarse(void) now.tv_nsec + mono.tv_nsec); return now; } + +/* + * The 64-bit jiffies value is not atomic - you MUST NOT read it + * without sampling the sequence number in xtime_lock. + * jiffies is defined in the linker script... + */ +void do_timer(unsigned long ticks) +{ + jiffies_64 += ticks; + update_wall_time(); + calc_global_load(ticks); +} + +/** + * get_xtime_and_monotonic_and_sleep_offset() - get xtime, wall_to_monotonic, + * and sleep offsets. + * @xtim: pointer to timespec to be set with xtime + * @wtom: pointer to timespec to be set with wall_to_monotonic + * @sleep: pointer to timespec to be set with time in suspend + */ +void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, + struct timespec *wtom, struct timespec *sleep) +{ + unsigned long seq; + + do { + seq = read_seqbegin(&xtime_lock); + *xtim = xtime; + *wtom = wall_to_monotonic; + *sleep = total_sleep_time; + } while (read_seqretry(&xtime_lock, seq)); +} + +/** + * xtime_update() - advances the timekeeping infrastructure + * @ticks: number of ticks, that have elapsed since the last call. + * + * Must be called with interrupts disabled. + */ +void xtime_update(unsigned long ticks) +{ + write_seqlock(&xtime_lock); + do_timer(ticks); + write_sequnlock(&xtime_lock); +} diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index ab8f5e33fa9..3258455549f 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -41,7 +41,7 @@ static void print_name_offset(struct seq_file *m, void *sym) char symname[KSYM_NAME_LEN]; if (lookup_symbol_name((unsigned long)sym, symname) < 0) - SEQ_printf(m, "<%p>", sym); + SEQ_printf(m, "<%pK>", sym); else SEQ_printf(m, "%s", symname); } @@ -79,26 +79,26 @@ print_active_timers(struct seq_file *m, struct hrtimer_clock_base *base, { struct hrtimer *timer, tmp; unsigned long next = 0, i; - struct rb_node *curr; + struct timerqueue_node *curr; unsigned long flags; next_one: i = 0; raw_spin_lock_irqsave(&base->cpu_base->lock, flags); - curr = base->first; + curr = timerqueue_getnext(&base->active); /* * Crude but we have to do this O(N*N) thing, because * we have to unlock the base when printing: */ while (curr && i < next) { - curr = rb_next(curr); + curr = timerqueue_iterate_next(curr); i++; } if (curr) { - timer = rb_entry(curr, struct hrtimer, node); + timer = container_of(curr, struct hrtimer, node); tmp = *timer; raw_spin_unlock_irqrestore(&base->cpu_base->lock, flags); @@ -112,7 +112,7 @@ next_one: static void print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now) { - SEQ_printf(m, " .base: %p\n", base); + SEQ_printf(m, " .base: %pK\n", base); SEQ_printf(m, " .index: %d\n", base->index); SEQ_printf(m, " .resolution: %Lu nsecs\n", diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c index 2f3b585b8d7..a5d0a3a85dd 100644 --- a/kernel/time/timer_stats.c +++ b/kernel/time/timer_stats.c @@ -236,7 +236,7 @@ void timer_stats_update_stats(void *timer, pid_t pid, void *startf, unsigned int timer_flag) { /* - * It doesnt matter which lock we take: + * It doesn't matter which lock we take: */ raw_spinlock_t *lock; struct entry *entry, input; diff --git a/kernel/timer.c b/kernel/timer.c index 68a9ae7679b..fd6198692b5 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -88,18 +88,6 @@ struct tvec_base boot_tvec_bases; EXPORT_SYMBOL(boot_tvec_bases); static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases; -/* - * Note that all tvec_bases are 2 byte aligned and lower bit of - * base in timer_list is guaranteed to be zero. Use the LSB to - * indicate whether the timer is deferrable. - * - * A deferrable timer will work normally when the system is busy, but - * will not cause a CPU to come out of idle just to service it; instead, - * the timer will be serviced when the CPU eventually wakes up with a - * subsequent non-deferrable timer. - */ -#define TBASE_DEFERRABLE_FLAG (0x1) - /* Functions below help us manage 'deferrable' flag */ static inline unsigned int tbase_get_deferrable(struct tvec_base *base) { @@ -113,8 +101,7 @@ static inline struct tvec_base *tbase_get_base(struct tvec_base *base) static inline void timer_set_deferrable(struct timer_list *timer) { - timer->base = ((struct tvec_base *)((unsigned long)(timer->base) | - TBASE_DEFERRABLE_FLAG)); + timer->base = TBASE_MAKE_DEFERRED(timer->base); } static inline void @@ -343,15 +330,6 @@ void set_timer_slack(struct timer_list *timer, int slack_hz) } EXPORT_SYMBOL_GPL(set_timer_slack); - -static inline void set_running_timer(struct tvec_base *base, - struct timer_list *timer) -{ -#ifdef CONFIG_SMP - base->running_timer = timer; -#endif -} - static void internal_add_timer(struct tvec_base *base, struct timer_list *timer) { unsigned long expires = timer->expires; @@ -426,6 +404,11 @@ static void timer_stats_account_timer(struct timer_list *timer) {} static struct debug_obj_descr timer_debug_descr; +static void *timer_debug_hint(void *addr) +{ + return ((struct timer_list *) addr)->function; +} + /* * fixup_init is called when: * - an active object is initialized @@ -499,6 +482,7 @@ static int timer_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr timer_debug_descr = { .name = "timer_list", + .debug_hint = timer_debug_hint, .fixup_init = timer_fixup_init, .fixup_activate = timer_fixup_activate, .fixup_free = timer_fixup_free, @@ -936,15 +920,12 @@ int del_timer(struct timer_list *timer) } EXPORT_SYMBOL(del_timer); -#ifdef CONFIG_SMP /** * try_to_del_timer_sync - Try to deactivate a timer * @timer: timer do del * * This function tries to deactivate a timer. Upon successful (ret >= 0) * exit the timer is not queued and the handler is not running on any CPU. - * - * It must not be called from interrupt contexts. */ int try_to_del_timer_sync(struct timer_list *timer) { @@ -973,6 +954,7 @@ out: } EXPORT_SYMBOL(try_to_del_timer_sync); +#ifdef CONFIG_SMP /** * del_timer_sync - deactivate a timer and wait for the handler to finish. * @timer: the timer to be deactivated @@ -988,6 +970,25 @@ EXPORT_SYMBOL(try_to_del_timer_sync); * add_timer_on(). Upon exit the timer is not queued and the handler is * not running on any CPU. * + * Note: You must not hold locks that are held in interrupt context + * while calling this function. Even if the lock has nothing to do + * with the timer in question. Here's why: + * + * CPU0 CPU1 + * ---- ---- + * <SOFTIRQ> + * call_timer_fn(); + * base->running_timer = mytimer; + * spin_lock_irq(somelock); + * <IRQ> + * spin_lock(somelock); + * del_timer_sync(mytimer); + * while (base->running_timer == mytimer); + * + * Now del_timer_sync() will never return and never release somelock. + * The interrupt on the other CPU is waiting to grab somelock but + * it has interrupted the softirq that CPU0 is waiting to finish. + * * The function returns whether it has deactivated a pending timer or not. */ int del_timer_sync(struct timer_list *timer) @@ -995,12 +996,20 @@ int del_timer_sync(struct timer_list *timer) #ifdef CONFIG_LOCKDEP unsigned long flags; + /* + * If lockdep gives a backtrace here, please reference + * the synchronization rules above. + */ local_irq_save(flags); lock_map_acquire(&timer->lockdep_map); lock_map_release(&timer->lockdep_map); local_irq_restore(flags); #endif - + /* + * don't use it in hardirq context, because it + * could lead to deadlock. + */ + WARN_ON(in_irq()); for (;;) { int ret = try_to_del_timer_sync(timer); if (ret >= 0) @@ -1111,7 +1120,7 @@ static inline void __run_timers(struct tvec_base *base) timer_stats_account_timer(timer); - set_running_timer(base, timer); + base->running_timer = timer; detach_timer(timer, 1); spin_unlock_irq(&base->lock); @@ -1119,7 +1128,7 @@ static inline void __run_timers(struct tvec_base *base) spin_lock_irq(&base->lock); } } - set_running_timer(base, NULL); + base->running_timer = NULL; spin_unlock_irq(&base->lock); } @@ -1249,9 +1258,15 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now, */ unsigned long get_next_timer_interrupt(unsigned long now) { - struct tvec_base *base = __get_cpu_var(tvec_bases); + struct tvec_base *base = __this_cpu_read(tvec_bases); unsigned long expires; + /* + * Pretend that there is no timer pending if the cpu is offline. + * Possible pending timers will be migrated later to an active cpu. + */ + if (cpu_is_offline(smp_processor_id())) + return now + NEXT_TIMER_MAX_DELTA; spin_lock(&base->lock); if (time_before_eq(base->next_timer, base->timer_jiffies)) base->next_timer = __next_timer_interrupt(base); @@ -1292,7 +1307,7 @@ void update_process_times(int user_tick) */ static void run_timer_softirq(struct softirq_action *h) { - struct tvec_base *base = __get_cpu_var(tvec_bases); + struct tvec_base *base = __this_cpu_read(tvec_bases); hrtimer_run_pending(); @@ -1309,19 +1324,6 @@ void run_local_timers(void) raise_softirq(TIMER_SOFTIRQ); } -/* - * The 64-bit jiffies value is not atomic - you MUST NOT read it - * without sampling the sequence number in xtime_lock. - * jiffies is defined in the linker script... - */ - -void do_timer(unsigned long ticks) -{ - jiffies_64 += ticks; - update_wall_time(); - calc_global_load(); -} - #ifdef __ARCH_WANT_SYS_ALARM /* diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index e04b8bcdef8..2ad39e556cb 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -69,6 +69,21 @@ config EVENT_TRACING select CONTEXT_SWITCH_TRACER bool +config EVENT_POWER_TRACING_DEPRECATED + depends on EVENT_TRACING + bool "Deprecated power event trace API, to be removed" + default y + help + Provides old power event types: + C-state/idle accounting events: + power:power_start + power:power_end + and old cpufreq accounting event: + power:power_frequency + This is for userspace compatibility + and will vanish after 5 kernel iterations, + namely 2.6.41. + config CONTEXT_SWITCH_TRACER bool @@ -126,7 +141,7 @@ if FTRACE config FUNCTION_TRACER bool "Kernel Function Tracer" depends on HAVE_FUNCTION_TRACER - select FRAME_POINTER if (!ARM_UNWIND) + select FRAME_POINTER if !ARM_UNWIND && !S390 && !MICROBLAZE select KALLSYMS select GENERIC_TRACER select CONTEXT_SWITCH_TRACER @@ -260,7 +275,7 @@ config PROFILE_ANNOTATED_BRANCHES This tracer profiles all the the likely and unlikely macros in the kernel. It will display the results in: - /sys/kernel/debug/tracing/profile_annotated_branch + /sys/kernel/debug/tracing/trace_stat/branch_annotated Note: this will add a significant overhead; only turn this on if you need to profile the system's use of these macros. @@ -273,7 +288,7 @@ config PROFILE_ALL_BRANCHES taken in the kernel is recorded whether it hit or miss. The results will be displayed in: - /sys/kernel/debug/tracing/profile_branch + /sys/kernel/debug/tracing/trace_stat/branch_all This option also enables the likely/unlikely profiler. diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index 53f338190b2..761c510a06c 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -52,7 +52,7 @@ obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o -obj-$(CONFIG_EVENT_TRACING) += power-traces.o +obj-$(CONFIG_TRACEPOINTS) += power-traces.o ifeq ($(CONFIG_TRACING),y) obj-$(CONFIG_KGDB_KDB) += trace_kdb.o endif diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index bc251ed6672..6957aa298df 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -138,6 +138,13 @@ void __trace_note_message(struct blk_trace *bt, const char *fmt, ...) !blk_tracer_enabled)) return; + /* + * If the BLK_TC_NOTIFY action mask isn't set, don't send any note + * message to the trace. + */ + if (!(bt->act_mask & BLK_TC_NOTIFY)) + return; + local_irq_save(flags); buf = per_cpu_ptr(bt->msg_data, smp_processor_id()); va_start(args, fmt); @@ -168,7 +175,6 @@ static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, static const u32 ddir_act[2] = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK_TC_WRITE) }; -#define BLK_TC_HARDBARRIER BLK_TC_BARRIER #define BLK_TC_RAHEAD BLK_TC_AHEAD /* The ilog2() calls fall out because they're constant */ @@ -196,7 +202,6 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, return; what |= ddir_act[rw & WRITE]; - what |= MASK_TC_BIT(rw, HARDBARRIER); what |= MASK_TC_BIT(rw, SYNC); what |= MASK_TC_BIT(rw, RAHEAD); what |= MASK_TC_BIT(rw, META); @@ -698,28 +703,21 @@ void blk_trace_shutdown(struct request_queue *q) * **/ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, - u32 what) + u32 what) { struct blk_trace *bt = q->blk_trace; - int rw = rq->cmd_flags & 0x03; if (likely(!bt)) return; - if (rq->cmd_flags & REQ_DISCARD) - rw |= REQ_DISCARD; - - if (rq->cmd_flags & REQ_SECURE) - rw |= REQ_SECURE; - if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { what |= BLK_TC_ACT(BLK_TC_PC); - __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, + __blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags, what, rq->errors, rq->cmd_len, rq->cmd); } else { what |= BLK_TC_ACT(BLK_TC_FS); - __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), rw, - what, rq->errors, 0, NULL); + __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), + rq->cmd_flags, what, rq->errors, 0, NULL); } } @@ -760,53 +758,58 @@ static void blk_add_trace_rq_complete(void *ignore, * @q: queue the io is for * @bio: the source bio * @what: the action + * @error: error, if any * * Description: * Records an action against a bio. Will log the bio offset + size. * **/ static void blk_add_trace_bio(struct request_queue *q, struct bio *bio, - u32 what) + u32 what, int error) { struct blk_trace *bt = q->blk_trace; if (likely(!bt)) return; + if (!error && !bio_flagged(bio, BIO_UPTODATE)) + error = EIO; + __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, - !bio_flagged(bio, BIO_UPTODATE), 0, NULL); + error, 0, NULL); } static void blk_add_trace_bio_bounce(void *ignore, struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_BOUNCE); + blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0); } static void blk_add_trace_bio_complete(void *ignore, - struct request_queue *q, struct bio *bio) + struct request_queue *q, struct bio *bio, + int error) { - blk_add_trace_bio(q, bio, BLK_TA_COMPLETE); + blk_add_trace_bio(q, bio, BLK_TA_COMPLETE, error); } static void blk_add_trace_bio_backmerge(void *ignore, struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); + blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0); } static void blk_add_trace_bio_frontmerge(void *ignore, struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); + blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0); } static void blk_add_trace_bio_queue(void *ignore, struct request_queue *q, struct bio *bio) { - blk_add_trace_bio(q, bio, BLK_TA_QUEUE); + blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0); } static void blk_add_trace_getrq(void *ignore, @@ -814,7 +817,7 @@ static void blk_add_trace_getrq(void *ignore, struct bio *bio, int rw) { if (bio) - blk_add_trace_bio(q, bio, BLK_TA_GETRQ); + blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0); else { struct blk_trace *bt = q->blk_trace; @@ -829,7 +832,7 @@ static void blk_add_trace_sleeprq(void *ignore, struct bio *bio, int rw) { if (bio) - blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ); + blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0); else { struct blk_trace *bt = q->blk_trace; @@ -847,29 +850,21 @@ static void blk_add_trace_plug(void *ignore, struct request_queue *q) __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); } -static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) +static void blk_add_trace_unplug(void *ignore, struct request_queue *q, + unsigned int depth, bool explicit) { struct blk_trace *bt = q->blk_trace; if (bt) { - unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; - __be64 rpdu = cpu_to_be64(pdu); - - __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, - sizeof(rpdu), &rpdu); - } -} - -static void blk_add_trace_unplug_timer(void *ignore, struct request_queue *q) -{ - struct blk_trace *bt = q->blk_trace; + __be64 rpdu = cpu_to_be64(depth); + u32 what; - if (bt) { - unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; - __be64 rpdu = cpu_to_be64(pdu); + if (explicit) + what = BLK_TA_UNPLUG_IO; + else + what = BLK_TA_UNPLUG_TIMER; - __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_TIMER, 0, - sizeof(rpdu), &rpdu); + __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); } } @@ -889,7 +884,7 @@ static void blk_add_trace_split(void *ignore, } /** - * blk_add_trace_remap - Add a trace for a remap operation + * blk_add_trace_bio_remap - Add a trace for a bio-remap operation * @ignore: trace callback data parameter (not used) * @q: queue the io is for * @bio: the source bio @@ -901,9 +896,9 @@ static void blk_add_trace_split(void *ignore, * it spans a stripe (or similar). Add a trace for that action. * **/ -static void blk_add_trace_remap(void *ignore, - struct request_queue *q, struct bio *bio, - dev_t dev, sector_t from) +static void blk_add_trace_bio_remap(void *ignore, + struct request_queue *q, struct bio *bio, + dev_t dev, sector_t from) { struct blk_trace *bt = q->blk_trace; struct blk_io_trace_remap r; @@ -1012,13 +1007,11 @@ static void blk_register_tracepoints(void) WARN_ON(ret); ret = register_trace_block_plug(blk_add_trace_plug, NULL); WARN_ON(ret); - ret = register_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); - WARN_ON(ret); - ret = register_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); + ret = register_trace_block_unplug(blk_add_trace_unplug, NULL); WARN_ON(ret); ret = register_trace_block_split(blk_add_trace_split, NULL); WARN_ON(ret); - ret = register_trace_block_remap(blk_add_trace_remap, NULL); + ret = register_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); WARN_ON(ret); ret = register_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); WARN_ON(ret); @@ -1027,10 +1020,9 @@ static void blk_register_tracepoints(void) static void blk_unregister_tracepoints(void) { unregister_trace_block_rq_remap(blk_add_trace_rq_remap, NULL); - unregister_trace_block_remap(blk_add_trace_remap, NULL); + unregister_trace_block_bio_remap(blk_add_trace_bio_remap, NULL); unregister_trace_block_split(blk_add_trace_split, NULL); - unregister_trace_block_unplug_io(blk_add_trace_unplug_io, NULL); - unregister_trace_block_unplug_timer(blk_add_trace_unplug_timer, NULL); + unregister_trace_block_unplug(blk_add_trace_unplug, NULL); unregister_trace_block_plug(blk_add_trace_plug, NULL); unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL); unregister_trace_block_getrq(blk_add_trace_getrq, NULL); @@ -1807,8 +1799,6 @@ void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) if (rw & REQ_RAHEAD) rwbs[i++] = 'A'; - if (rw & REQ_HARDBARRIER) - rwbs[i++] = 'B'; if (rw & REQ_SYNC) rwbs[i++] = 'S'; if (rw & REQ_META) @@ -1819,21 +1809,5 @@ void blk_fill_rwbs(char *rwbs, u32 rw, int bytes) rwbs[i] = '\0'; } -void blk_fill_rwbs_rq(char *rwbs, struct request *rq) -{ - int rw = rq->cmd_flags & 0x03; - int bytes; - - if (rq->cmd_flags & REQ_DISCARD) - rw |= REQ_DISCARD; - - if (rq->cmd_flags & REQ_SECURE) - rw |= REQ_SECURE; - - bytes = blk_rq_bytes(rq); - - blk_fill_rwbs(rwbs, rw, bytes); -} - #endif /* CONFIG_EVENT_TRACING */ diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f3dadae8388..d017c2c82c4 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -39,20 +39,26 @@ #include "trace_stat.h" #define FTRACE_WARN_ON(cond) \ - do { \ - if (WARN_ON(cond)) \ + ({ \ + int ___r = cond; \ + if (WARN_ON(___r)) \ ftrace_kill(); \ - } while (0) + ___r; \ + }) #define FTRACE_WARN_ON_ONCE(cond) \ - do { \ - if (WARN_ON_ONCE(cond)) \ + ({ \ + int ___r = cond; \ + if (WARN_ON_ONCE(___r)) \ ftrace_kill(); \ - } while (0) + ___r; \ + }) /* hash bits for specific function selection */ #define FTRACE_HASH_BITS 7 #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) +#define FTRACE_HASH_DEFAULT_BITS 10 +#define FTRACE_HASH_MAX_BITS 12 /* ftrace_enabled is a method to turn ftrace on or off */ int ftrace_enabled __read_mostly; @@ -81,23 +87,29 @@ static struct ftrace_ops ftrace_list_end __read_mostly = .func = ftrace_stub, }; -static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; +static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end; +static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; +static struct ftrace_ops global_ops; + +static void +ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip); /* - * Traverse the ftrace_list, invoking all entries. The reason that we + * Traverse the ftrace_global_list, invoking all entries. The reason that we * can use rcu_dereference_raw() is that elements removed from this list * are simply leaked, so there is no need to interact with a grace-period * mechanism. The rcu_dereference_raw() calls are needed to handle - * concurrent insertions into the ftrace_list. + * concurrent insertions into the ftrace_global_list. * * Silly Alpha and silly pointer-speculation compiler optimizations! */ -static void ftrace_list_func(unsigned long ip, unsigned long parent_ip) +static void ftrace_global_list_func(unsigned long ip, + unsigned long parent_ip) { - struct ftrace_ops *op = rcu_dereference_raw(ftrace_list); /*see above*/ + struct ftrace_ops *op = rcu_dereference_raw(ftrace_global_list); /*see above*/ while (op != &ftrace_list_end) { op->func(ip, parent_ip); @@ -147,46 +159,69 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) } #endif -static int __register_ftrace_function(struct ftrace_ops *ops) +static void update_global_ops(void) { - ops->next = ftrace_list; + ftrace_func_t func; + /* - * We are entering ops into the ftrace_list but another - * CPU might be walking that list. We need to make sure - * the ops->next pointer is valid before another CPU sees - * the ops pointer included into the ftrace_list. + * If there's only one function registered, then call that + * function directly. Otherwise, we need to iterate over the + * registered callers. */ - rcu_assign_pointer(ftrace_list, ops); + if (ftrace_global_list == &ftrace_list_end || + ftrace_global_list->next == &ftrace_list_end) + func = ftrace_global_list->func; + else + func = ftrace_global_list_func; - if (ftrace_enabled) { - ftrace_func_t func; + /* If we filter on pids, update to use the pid function */ + if (!list_empty(&ftrace_pids)) { + set_ftrace_pid_function(func); + func = ftrace_pid_func; + } - if (ops->next == &ftrace_list_end) - func = ops->func; - else - func = ftrace_list_func; + global_ops.func = func; +} - if (!list_empty(&ftrace_pids)) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } +static void update_ftrace_function(void) +{ + ftrace_func_t func; + + update_global_ops(); + + /* + * If we are at the end of the list and this ops is + * not dynamic, then have the mcount trampoline call + * the function directly + */ + if (ftrace_ops_list == &ftrace_list_end || + (ftrace_ops_list->next == &ftrace_list_end && + !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC))) + func = ftrace_ops_list->func; + else + func = ftrace_ops_list_func; - /* - * For one func, simply call it directly. - * For more than one func, call the chain. - */ #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; + ftrace_trace_function = func; #else - __ftrace_trace_function = func; - ftrace_trace_function = ftrace_test_stop_func; + __ftrace_trace_function = func; + ftrace_trace_function = ftrace_test_stop_func; #endif - } +} - return 0; +static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) +{ + ops->next = *list; + /* + * We are entering ops into the list but another + * CPU might be walking that list. We need to make sure + * the ops->next pointer is valid before another CPU sees + * the ops pointer included into the list. + */ + rcu_assign_pointer(*list, ops); } -static int __unregister_ftrace_function(struct ftrace_ops *ops) +static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { struct ftrace_ops **p; @@ -194,13 +229,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) * If we are removing the last function, then simply point * to the ftrace_stub. */ - if (ftrace_list == ops && ops->next == &ftrace_list_end) { - ftrace_trace_function = ftrace_stub; - ftrace_list = &ftrace_list_end; + if (*list == ops && ops->next == &ftrace_list_end) { + *list = &ftrace_list_end; return 0; } - for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) + for (p = list; *p != &ftrace_list_end; p = &(*p)->next) if (*p == ops) break; @@ -208,53 +242,83 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) return -1; *p = (*p)->next; + return 0; +} - if (ftrace_enabled) { - /* If we only have one func left, then call that directly */ - if (ftrace_list->next == &ftrace_list_end) { - ftrace_func_t func = ftrace_list->func; +static int __register_ftrace_function(struct ftrace_ops *ops) +{ + if (ftrace_disabled) + return -ENODEV; - if (!list_empty(&ftrace_pids)) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; -#else - __ftrace_trace_function = func; -#endif - } - } + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; + + if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) + return -EBUSY; + + if (!core_kernel_data((unsigned long)ops)) + ops->flags |= FTRACE_OPS_FL_DYNAMIC; + + if (ops->flags & FTRACE_OPS_FL_GLOBAL) { + int first = ftrace_global_list == &ftrace_list_end; + add_ftrace_ops(&ftrace_global_list, ops); + ops->flags |= FTRACE_OPS_FL_ENABLED; + if (first) + add_ftrace_ops(&ftrace_ops_list, &global_ops); + } else + add_ftrace_ops(&ftrace_ops_list, ops); + + if (ftrace_enabled) + update_ftrace_function(); return 0; } -static void ftrace_update_pid_func(void) +static int __unregister_ftrace_function(struct ftrace_ops *ops) { - ftrace_func_t func; + int ret; - if (ftrace_trace_function == ftrace_stub) - return; + if (ftrace_disabled) + return -ENODEV; -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - func = ftrace_trace_function; -#else - func = __ftrace_trace_function; -#endif + if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) + return -EBUSY; - if (!list_empty(&ftrace_pids)) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } else { - if (func == ftrace_pid_func) - func = ftrace_pid_function; - } + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; -#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST - ftrace_trace_function = func; -#else - __ftrace_trace_function = func; -#endif + if (ops->flags & FTRACE_OPS_FL_GLOBAL) { + ret = remove_ftrace_ops(&ftrace_global_list, ops); + if (!ret && ftrace_global_list == &ftrace_list_end) + ret = remove_ftrace_ops(&ftrace_ops_list, &global_ops); + if (!ret) + ops->flags &= ~FTRACE_OPS_FL_ENABLED; + } else + ret = remove_ftrace_ops(&ftrace_ops_list, ops); + + if (ret < 0) + return ret; + + if (ftrace_enabled) + update_ftrace_function(); + + /* + * Dynamic ops may be freed, we must make sure that all + * callers are done before leaving this function. + */ + if (ops->flags & FTRACE_OPS_FL_DYNAMIC) + synchronize_sched(); + + return 0; +} + +static void ftrace_update_pid_func(void) +{ + /* Only do something if we are tracing something */ + if (ftrace_trace_function == ftrace_stub) + return; + + update_ftrace_function(); } #ifdef CONFIG_FUNCTION_PROFILER @@ -888,8 +952,35 @@ enum { FTRACE_START_FUNC_RET = (1 << 3), FTRACE_STOP_FUNC_RET = (1 << 4), }; +struct ftrace_func_entry { + struct hlist_node hlist; + unsigned long ip; +}; + +struct ftrace_hash { + unsigned long size_bits; + struct hlist_head *buckets; + unsigned long count; + struct rcu_head rcu; +}; -static int ftrace_filtered; +/* + * We make these constant because no one should touch them, + * but they are used as the default "empty hash", to avoid allocating + * it all the time. These are in a read only section such that if + * anyone does try to modify it, it will cause an exception. + */ +static const struct hlist_head empty_buckets[1]; +static const struct ftrace_hash empty_hash = { + .buckets = (struct hlist_head *)empty_buckets, +}; +#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) + +static struct ftrace_ops global_ops = { + .func = ftrace_stub, + .notrace_hash = EMPTY_HASH, + .filter_hash = EMPTY_HASH, +}; static struct dyn_ftrace *ftrace_new_addrs; @@ -912,6 +1003,269 @@ static struct ftrace_page *ftrace_pages; static struct dyn_ftrace *ftrace_free_records; +static struct ftrace_func_entry * +ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) +{ + unsigned long key; + struct ftrace_func_entry *entry; + struct hlist_head *hhd; + struct hlist_node *n; + + if (!hash->count) + return NULL; + + if (hash->size_bits > 0) + key = hash_long(ip, hash->size_bits); + else + key = 0; + + hhd = &hash->buckets[key]; + + hlist_for_each_entry_rcu(entry, n, hhd, hlist) { + if (entry->ip == ip) + return entry; + } + return NULL; +} + +static void __add_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + struct hlist_head *hhd; + unsigned long key; + + if (hash->size_bits) + key = hash_long(entry->ip, hash->size_bits); + else + key = 0; + + hhd = &hash->buckets[key]; + hlist_add_head(&entry->hlist, hhd); + hash->count++; +} + +static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) +{ + struct ftrace_func_entry *entry; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + entry->ip = ip; + __add_hash_entry(hash, entry); + + return 0; +} + +static void +free_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + hlist_del(&entry->hlist); + kfree(entry); + hash->count--; +} + +static void +remove_hash_entry(struct ftrace_hash *hash, + struct ftrace_func_entry *entry) +{ + hlist_del(&entry->hlist); + hash->count--; +} + +static void ftrace_hash_clear(struct ftrace_hash *hash) +{ + struct hlist_head *hhd; + struct hlist_node *tp, *tn; + struct ftrace_func_entry *entry; + int size = 1 << hash->size_bits; + int i; + + if (!hash->count) + return; + + for (i = 0; i < size; i++) { + hhd = &hash->buckets[i]; + hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) + free_hash_entry(hash, entry); + } + FTRACE_WARN_ON(hash->count); +} + +static void free_ftrace_hash(struct ftrace_hash *hash) +{ + if (!hash || hash == EMPTY_HASH) + return; + ftrace_hash_clear(hash); + kfree(hash->buckets); + kfree(hash); +} + +static void __free_ftrace_hash_rcu(struct rcu_head *rcu) +{ + struct ftrace_hash *hash; + + hash = container_of(rcu, struct ftrace_hash, rcu); + free_ftrace_hash(hash); +} + +static void free_ftrace_hash_rcu(struct ftrace_hash *hash) +{ + if (!hash || hash == EMPTY_HASH) + return; + call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); +} + +static struct ftrace_hash *alloc_ftrace_hash(int size_bits) +{ + struct ftrace_hash *hash; + int size; + + hash = kzalloc(sizeof(*hash), GFP_KERNEL); + if (!hash) + return NULL; + + size = 1 << size_bits; + hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL); + + if (!hash->buckets) { + kfree(hash); + return NULL; + } + + hash->size_bits = size_bits; + + return hash; +} + +static struct ftrace_hash * +alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) +{ + struct ftrace_func_entry *entry; + struct ftrace_hash *new_hash; + struct hlist_node *tp; + int size; + int ret; + int i; + + new_hash = alloc_ftrace_hash(size_bits); + if (!new_hash) + return NULL; + + /* Empty hash? */ + if (!hash || !hash->count) + return new_hash; + + size = 1 << hash->size_bits; + for (i = 0; i < size; i++) { + hlist_for_each_entry(entry, tp, &hash->buckets[i], hlist) { + ret = add_hash_entry(new_hash, entry->ip); + if (ret < 0) + goto free_hash; + } + } + + FTRACE_WARN_ON(new_hash->count != hash->count); + + return new_hash; + + free_hash: + free_ftrace_hash(new_hash); + return NULL; +} + +static int +ftrace_hash_move(struct ftrace_hash **dst, struct ftrace_hash *src) +{ + struct ftrace_func_entry *entry; + struct hlist_node *tp, *tn; + struct hlist_head *hhd; + struct ftrace_hash *old_hash; + struct ftrace_hash *new_hash; + unsigned long key; + int size = src->count; + int bits = 0; + int i; + + /* + * If the new source is empty, just free dst and assign it + * the empty_hash. + */ + if (!src->count) { + free_ftrace_hash_rcu(*dst); + rcu_assign_pointer(*dst, EMPTY_HASH); + return 0; + } + + /* + * Make the hash size about 1/2 the # found + */ + for (size /= 2; size; size >>= 1) + bits++; + + /* Don't allocate too much */ + if (bits > FTRACE_HASH_MAX_BITS) + bits = FTRACE_HASH_MAX_BITS; + + new_hash = alloc_ftrace_hash(bits); + if (!new_hash) + return -ENOMEM; + + size = 1 << src->size_bits; + for (i = 0; i < size; i++) { + hhd = &src->buckets[i]; + hlist_for_each_entry_safe(entry, tp, tn, hhd, hlist) { + if (bits > 0) + key = hash_long(entry->ip, bits); + else + key = 0; + remove_hash_entry(src, entry); + __add_hash_entry(new_hash, entry); + } + } + + old_hash = *dst; + rcu_assign_pointer(*dst, new_hash); + free_ftrace_hash_rcu(old_hash); + + return 0; +} + +/* + * Test the hashes for this ops to see if we want to call + * the ops->func or not. + * + * It's a match if the ip is in the ops->filter_hash or + * the filter_hash does not exist or is empty, + * AND + * the ip is not in the ops->notrace_hash. + * + * This needs to be called with preemption disabled as + * the hashes are freed with call_rcu_sched(). + */ +static int +ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) +{ + struct ftrace_hash *filter_hash; + struct ftrace_hash *notrace_hash; + int ret; + + filter_hash = rcu_dereference_raw(ops->filter_hash); + notrace_hash = rcu_dereference_raw(ops->notrace_hash); + + if ((!filter_hash || !filter_hash->count || + ftrace_lookup_ip(filter_hash, ip)) && + (!notrace_hash || !notrace_hash->count || + !ftrace_lookup_ip(notrace_hash, ip))) + ret = 1; + else + ret = 0; + + return ret; +} + /* * This is a double for. Do not use 'break' to break out of the loop, * you must use a goto. @@ -926,6 +1280,105 @@ static struct dyn_ftrace *ftrace_free_records; } \ } +static void __ftrace_hash_rec_update(struct ftrace_ops *ops, + int filter_hash, + bool inc) +{ + struct ftrace_hash *hash; + struct ftrace_hash *other_hash; + struct ftrace_page *pg; + struct dyn_ftrace *rec; + int count = 0; + int all = 0; + + /* Only update if the ops has been registered */ + if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) + return; + + /* + * In the filter_hash case: + * If the count is zero, we update all records. + * Otherwise we just update the items in the hash. + * + * In the notrace_hash case: + * We enable the update in the hash. + * As disabling notrace means enabling the tracing, + * and enabling notrace means disabling, the inc variable + * gets inversed. + */ + if (filter_hash) { + hash = ops->filter_hash; + other_hash = ops->notrace_hash; + if (!hash || !hash->count) + all = 1; + } else { + inc = !inc; + hash = ops->notrace_hash; + other_hash = ops->filter_hash; + /* + * If the notrace hash has no items, + * then there's nothing to do. + */ + if (hash && !hash->count) + return; + } + + do_for_each_ftrace_rec(pg, rec) { + int in_other_hash = 0; + int in_hash = 0; + int match = 0; + + if (all) { + /* + * Only the filter_hash affects all records. + * Update if the record is not in the notrace hash. + */ + if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) + match = 1; + } else { + in_hash = hash && !!ftrace_lookup_ip(hash, rec->ip); + in_other_hash = other_hash && !!ftrace_lookup_ip(other_hash, rec->ip); + + /* + * + */ + if (filter_hash && in_hash && !in_other_hash) + match = 1; + else if (!filter_hash && in_hash && + (in_other_hash || !other_hash->count)) + match = 1; + } + if (!match) + continue; + + if (inc) { + rec->flags++; + if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX)) + return; + } else { + if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0)) + return; + rec->flags--; + } + count++; + /* Shortcut, if we handled all records, we are done. */ + if (!all && count == hash->count) + return; + } while_for_each_ftrace_rec(); +} + +static void ftrace_hash_rec_disable(struct ftrace_ops *ops, + int filter_hash) +{ + __ftrace_hash_rec_update(ops, filter_hash, 0); +} + +static void ftrace_hash_rec_enable(struct ftrace_ops *ops, + int filter_hash) +{ + __ftrace_hash_rec_update(ops, filter_hash, 1); +} + static void ftrace_free_rec(struct dyn_ftrace *rec) { rec->freelist = ftrace_free_records; @@ -1047,18 +1500,18 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable) ftrace_addr = (unsigned long)FTRACE_ADDR; /* - * If this record is not to be traced or we want to disable it, - * then disable it. + * If we are enabling tracing: * - * If we want to enable it and filtering is off, then enable it. + * If the record has a ref count, then we need to enable it + * because someone is using it. * - * If we want to enable it and filtering is on, enable it only if - * it's filtered + * Otherwise we make sure its disabled. + * + * If we are disabling tracing, then disable all records that + * are enabled. */ - if (enable && !(rec->flags & FTRACE_FL_NOTRACE)) { - if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER)) - flag = FTRACE_FL_ENABLED; - } + if (enable && (rec->flags & ~FTRACE_FL_MASK)) + flag = FTRACE_FL_ENABLED; /* If the state of this record hasn't changed, then do nothing */ if ((rec->flags & FTRACE_FL_ENABLED) == flag) @@ -1079,19 +1532,16 @@ static void ftrace_replace_code(int enable) struct ftrace_page *pg; int failed; + if (unlikely(ftrace_disabled)) + return; + do_for_each_ftrace_rec(pg, rec) { - /* - * Skip over free records, records that have - * failed and not converted. - */ - if (rec->flags & FTRACE_FL_FREE || - rec->flags & FTRACE_FL_FAILED || - !(rec->flags & FTRACE_FL_CONVERTED)) + /* Skip over free records */ + if (rec->flags & FTRACE_FL_FREE) continue; failed = __ftrace_replace_code(rec, enable); if (failed) { - rec->flags |= FTRACE_FL_FAILED; ftrace_bug(failed, rec->ip); /* Stop processing */ return; @@ -1107,10 +1557,12 @@ ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) ip = rec->ip; + if (unlikely(ftrace_disabled)) + return 0; + ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); if (ret) { ftrace_bug(ret, ip); - rec->flags |= FTRACE_FL_FAILED; return 0; } return 1; @@ -1171,6 +1623,7 @@ static void ftrace_run_update_code(int command) static ftrace_func_t saved_ftrace_func; static int ftrace_start_up; +static int global_start_up; static void ftrace_startup_enable(int command) { @@ -1185,19 +1638,36 @@ static void ftrace_startup_enable(int command) ftrace_run_update_code(command); } -static void ftrace_startup(int command) +static void ftrace_startup(struct ftrace_ops *ops, int command) { + bool hash_enable = true; + if (unlikely(ftrace_disabled)) return; ftrace_start_up++; command |= FTRACE_ENABLE_CALLS; + /* ops marked global share the filter hashes */ + if (ops->flags & FTRACE_OPS_FL_GLOBAL) { + ops = &global_ops; + /* Don't update hash if global is already set */ + if (global_start_up) + hash_enable = false; + global_start_up++; + } + + ops->flags |= FTRACE_OPS_FL_ENABLED; + if (hash_enable) + ftrace_hash_rec_enable(ops, 1); + ftrace_startup_enable(command); } -static void ftrace_shutdown(int command) +static void ftrace_shutdown(struct ftrace_ops *ops, int command) { + bool hash_disable = true; + if (unlikely(ftrace_disabled)) return; @@ -1209,6 +1679,23 @@ static void ftrace_shutdown(int command) */ WARN_ON_ONCE(ftrace_start_up < 0); + if (ops->flags & FTRACE_OPS_FL_GLOBAL) { + ops = &global_ops; + global_start_up--; + WARN_ON_ONCE(global_start_up < 0); + /* Don't update hash if global still has users */ + if (global_start_up) { + WARN_ON_ONCE(!ftrace_start_up); + hash_disable = false; + } + } + + if (hash_disable) + ftrace_hash_rec_disable(ops, 1); + + if (ops != &global_ops || !global_start_up) + ops->flags &= ~FTRACE_OPS_FL_ENABLED; + if (!ftrace_start_up) command |= FTRACE_DISABLE_CALLS; @@ -1268,15 +1755,15 @@ static int ftrace_update_code(struct module *mod) p->flags = 0L; /* - * Do the initial record convertion from mcount jump + * Do the initial record conversion from mcount jump * to the NOP instructions. */ if (!ftrace_code_disable(mod, p)) { ftrace_free_rec(p); - continue; + /* Game over */ + break; } - p->flags |= FTRACE_FL_CONVERTED; ftrace_update_cnt++; /* @@ -1351,9 +1838,9 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init) enum { FTRACE_ITER_FILTER = (1 << 0), FTRACE_ITER_NOTRACE = (1 << 1), - FTRACE_ITER_FAILURES = (1 << 2), - FTRACE_ITER_PRINTALL = (1 << 3), - FTRACE_ITER_HASH = (1 << 4), + FTRACE_ITER_PRINTALL = (1 << 2), + FTRACE_ITER_HASH = (1 << 3), + FTRACE_ITER_ENABLED = (1 << 4), }; #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ @@ -1365,6 +1852,8 @@ struct ftrace_iterator { struct dyn_ftrace *func; struct ftrace_func_probe *probe; struct trace_parser parser; + struct ftrace_hash *hash; + struct ftrace_ops *ops; int hidx; int idx; unsigned flags; @@ -1461,13 +1950,17 @@ static void * t_next(struct seq_file *m, void *v, loff_t *pos) { struct ftrace_iterator *iter = m->private; + struct ftrace_ops *ops = &global_ops; struct dyn_ftrace *rec = NULL; + if (unlikely(ftrace_disabled)) + return NULL; + if (iter->flags & FTRACE_ITER_HASH) return t_hash_next(m, pos); (*pos)++; - iter->pos = *pos; + iter->pos = iter->func_pos = *pos; if (iter->flags & FTRACE_ITER_PRINTALL) return t_hash_start(m, pos); @@ -1483,17 +1976,15 @@ t_next(struct seq_file *m, void *v, loff_t *pos) rec = &iter->pg->records[iter->idx++]; if ((rec->flags & FTRACE_FL_FREE) || - (!(iter->flags & FTRACE_ITER_FAILURES) && - (rec->flags & FTRACE_FL_FAILED)) || - - ((iter->flags & FTRACE_ITER_FAILURES) && - !(rec->flags & FTRACE_FL_FAILED)) || - ((iter->flags & FTRACE_ITER_FILTER) && - !(rec->flags & FTRACE_FL_FILTER)) || + !(ftrace_lookup_ip(ops->filter_hash, rec->ip))) || ((iter->flags & FTRACE_ITER_NOTRACE) && - !(rec->flags & FTRACE_FL_NOTRACE))) { + !ftrace_lookup_ip(ops->notrace_hash, rec->ip)) || + + ((iter->flags & FTRACE_ITER_ENABLED) && + !(rec->flags & ~FTRACE_FL_MASK))) { + rec = NULL; goto retry; } @@ -1502,7 +1993,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos) if (!rec) return t_hash_start(m, pos); - iter->func_pos = *pos; iter->func = rec; return iter; @@ -1518,10 +2008,15 @@ static void reset_iter_read(struct ftrace_iterator *iter) static void *t_start(struct seq_file *m, loff_t *pos) { struct ftrace_iterator *iter = m->private; + struct ftrace_ops *ops = &global_ops; void *p = NULL; loff_t l; mutex_lock(&ftrace_lock); + + if (unlikely(ftrace_disabled)) + return NULL; + /* * If an lseek was done, then reset and start from beginning. */ @@ -1533,7 +2028,7 @@ static void *t_start(struct seq_file *m, loff_t *pos) * off, we can short cut and just print out that all * functions are enabled. */ - if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) { + if (iter->flags & FTRACE_ITER_FILTER && !ops->filter_hash->count) { if (*pos > 0) return t_hash_start(m, pos); iter->flags |= FTRACE_ITER_PRINTALL; @@ -1591,7 +2086,11 @@ static int t_show(struct seq_file *m, void *v) if (!rec) return 0; - seq_printf(m, "%ps\n", (void *)rec->ip); + seq_printf(m, "%ps", (void *)rec->ip); + if (iter->flags & FTRACE_ITER_ENABLED) + seq_printf(m, " (%ld)", + rec->flags & ~FTRACE_FL_MASK); + seq_printf(m, "\n"); return 0; } @@ -1631,44 +2130,46 @@ ftrace_avail_open(struct inode *inode, struct file *file) } static int -ftrace_failures_open(struct inode *inode, struct file *file) +ftrace_enabled_open(struct inode *inode, struct file *file) { - int ret; - struct seq_file *m; struct ftrace_iterator *iter; + int ret; - ret = ftrace_avail_open(inode, file); + if (unlikely(ftrace_disabled)) + return -ENODEV; + + iter = kzalloc(sizeof(*iter), GFP_KERNEL); + if (!iter) + return -ENOMEM; + + iter->pg = ftrace_pages_start; + iter->flags = FTRACE_ITER_ENABLED; + + ret = seq_open(file, &show_ftrace_seq_ops); if (!ret) { - m = file->private_data; - iter = m->private; - iter->flags = FTRACE_ITER_FAILURES; + struct seq_file *m = file->private_data; + + m->private = iter; + } else { + kfree(iter); } return ret; } - -static void ftrace_filter_reset(int enable) +static void ftrace_filter_reset(struct ftrace_hash *hash) { - struct ftrace_page *pg; - struct dyn_ftrace *rec; - unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - mutex_lock(&ftrace_lock); - if (enable) - ftrace_filtered = 0; - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; - rec->flags &= ~type; - } while_for_each_ftrace_rec(); + ftrace_hash_clear(hash); mutex_unlock(&ftrace_lock); } static int -ftrace_regex_open(struct inode *inode, struct file *file, int enable) +ftrace_regex_open(struct ftrace_ops *ops, int flag, + struct inode *inode, struct file *file) { struct ftrace_iterator *iter; + struct ftrace_hash *hash; int ret = 0; if (unlikely(ftrace_disabled)) @@ -1683,21 +2184,42 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable) return -ENOMEM; } + if (flag & FTRACE_ITER_NOTRACE) + hash = ops->notrace_hash; + else + hash = ops->filter_hash; + + iter->ops = ops; + iter->flags = flag; + + if (file->f_mode & FMODE_WRITE) { + mutex_lock(&ftrace_lock); + iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); + mutex_unlock(&ftrace_lock); + + if (!iter->hash) { + trace_parser_put(&iter->parser); + kfree(iter); + return -ENOMEM; + } + } + mutex_lock(&ftrace_regex_lock); + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) - ftrace_filter_reset(enable); + ftrace_filter_reset(iter->hash); if (file->f_mode & FMODE_READ) { iter->pg = ftrace_pages_start; - iter->flags = enable ? FTRACE_ITER_FILTER : - FTRACE_ITER_NOTRACE; ret = seq_open(file, &show_ftrace_seq_ops); if (!ret) { struct seq_file *m = file->private_data; m->private = iter; } else { + /* Failed */ + free_ftrace_hash(iter->hash); trace_parser_put(&iter->parser); kfree(iter); } @@ -1711,13 +2233,15 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable) static int ftrace_filter_open(struct inode *inode, struct file *file) { - return ftrace_regex_open(inode, file, 1); + return ftrace_regex_open(&global_ops, FTRACE_ITER_FILTER, + inode, file); } static int ftrace_notrace_open(struct inode *inode, struct file *file) { - return ftrace_regex_open(inode, file, 0); + return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE, + inode, file); } static loff_t @@ -1762,86 +2286,99 @@ static int ftrace_match(char *str, char *regex, int len, int type) } static int -ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type) +enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) +{ + struct ftrace_func_entry *entry; + int ret = 0; + + entry = ftrace_lookup_ip(hash, rec->ip); + if (not) { + /* Do nothing if it doesn't exist */ + if (!entry) + return 0; + + free_hash_entry(hash, entry); + } else { + /* Do nothing if it exists */ + if (entry) + return 0; + + ret = add_hash_entry(hash, rec->ip); + } + return ret; +} + +static int +ftrace_match_record(struct dyn_ftrace *rec, char *mod, + char *regex, int len, int type) { char str[KSYM_SYMBOL_LEN]; + char *modname; + + kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); + + if (mod) { + /* module lookup requires matching the module */ + if (!modname || strcmp(modname, mod)) + return 0; + + /* blank search means to match all funcs in the mod */ + if (!len) + return 1; + } - kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); return ftrace_match(str, regex, len, type); } -static int ftrace_match_records(char *buff, int len, int enable) +static int +match_records(struct ftrace_hash *hash, char *buff, + int len, char *mod, int not) { - unsigned int search_len; + unsigned search_len = 0; struct ftrace_page *pg; struct dyn_ftrace *rec; - unsigned long flag; - char *search; - int type; - int not; + int type = MATCH_FULL; + char *search = buff; int found = 0; + int ret; - flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; - type = filter_parse_regex(buff, len, &search, ¬); - - search_len = strlen(search); + if (len) { + type = filter_parse_regex(buff, len, &search, ¬); + search_len = strlen(search); + } mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; + if (unlikely(ftrace_disabled)) + goto out_unlock; - if (ftrace_match_record(rec, search, search_len, type)) { - if (not) - rec->flags &= ~flag; - else - rec->flags |= flag; + do_for_each_ftrace_rec(pg, rec) { + + if (ftrace_match_record(rec, mod, search, search_len, type)) { + ret = enter_record(hash, rec, not); + if (ret < 0) { + found = ret; + goto out_unlock; + } found = 1; } - /* - * Only enable filtering if we have a function that - * is filtered on. - */ - if (enable && (rec->flags & FTRACE_FL_FILTER)) - ftrace_filtered = 1; } while_for_each_ftrace_rec(); + out_unlock: mutex_unlock(&ftrace_lock); return found; } static int -ftrace_match_module_record(struct dyn_ftrace *rec, char *mod, - char *regex, int len, int type) +ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) { - char str[KSYM_SYMBOL_LEN]; - char *modname; - - kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); - - if (!modname || strcmp(modname, mod)) - return 0; - - /* blank search means to match all funcs in the mod */ - if (len) - return ftrace_match(str, regex, len, type); - else - return 1; + return match_records(hash, buff, len, NULL, 0); } -static int ftrace_match_module_records(char *buff, char *mod, int enable) +static int +ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) { - unsigned search_len = 0; - struct ftrace_page *pg; - struct dyn_ftrace *rec; - int type = MATCH_FULL; - char *search = buff; - unsigned long flag; int not = 0; - int found = 0; - - flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE; /* blank or '*' mean the same */ if (strcmp(buff, "*") == 0) @@ -1853,32 +2390,7 @@ static int ftrace_match_module_records(char *buff, char *mod, int enable) not = 1; } - if (strlen(buff)) { - type = filter_parse_regex(buff, strlen(buff), &search, ¬); - search_len = strlen(search); - } - - mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - - if (rec->flags & FTRACE_FL_FAILED) - continue; - - if (ftrace_match_module_record(rec, mod, - search, search_len, type)) { - if (not) - rec->flags &= ~flag; - else - rec->flags |= flag; - found = 1; - } - if (enable && (rec->flags & FTRACE_FL_FILTER)) - ftrace_filtered = 1; - - } while_for_each_ftrace_rec(); - mutex_unlock(&ftrace_lock); - - return found; + return match_records(hash, buff, strlen(buff), mod, not); } /* @@ -1889,7 +2401,10 @@ static int ftrace_match_module_records(char *buff, char *mod, int enable) static int ftrace_mod_callback(char *func, char *cmd, char *param, int enable) { + struct ftrace_ops *ops = &global_ops; + struct ftrace_hash *hash; char *mod; + int ret = -EINVAL; /* * cmd == 'mod' because we only registered this func @@ -1901,15 +2416,24 @@ ftrace_mod_callback(char *func, char *cmd, char *param, int enable) /* we must have a module name */ if (!param) - return -EINVAL; + return ret; mod = strsep(¶m, ":"); if (!strlen(mod)) - return -EINVAL; + return ret; - if (ftrace_match_module_records(func, mod, enable)) - return 0; - return -EINVAL; + if (enable) + hash = ops->filter_hash; + else + hash = ops->notrace_hash; + + ret = ftrace_match_module_records(hash, func, mod); + if (!ret) + ret = -EINVAL; + if (ret < 0) + return ret; + + return 0; } static struct ftrace_func_command ftrace_mod_cmd = { @@ -1960,6 +2484,7 @@ static int ftrace_probe_registered; static void __enable_ftrace_function_probe(void) { + int ret; int i; if (ftrace_probe_registered) @@ -1974,13 +2499,16 @@ static void __enable_ftrace_function_probe(void) if (i == FTRACE_FUNC_HASHSIZE) return; - __register_ftrace_function(&trace_probe_ops); - ftrace_startup(0); + ret = __register_ftrace_function(&trace_probe_ops); + if (!ret) + ftrace_startup(&trace_probe_ops, 0); + ftrace_probe_registered = 1; } static void __disable_ftrace_function_probe(void) { + int ret; int i; if (!ftrace_probe_registered) @@ -1993,8 +2521,10 @@ static void __disable_ftrace_function_probe(void) } /* no more funcs left */ - __unregister_ftrace_function(&trace_probe_ops); - ftrace_shutdown(0); + ret = __unregister_ftrace_function(&trace_probe_ops); + if (!ret) + ftrace_shutdown(&trace_probe_ops, 0); + ftrace_probe_registered = 0; } @@ -2030,12 +2560,13 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, return -EINVAL; mutex_lock(&ftrace_lock); - do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & FTRACE_FL_FAILED) - continue; + if (unlikely(ftrace_disabled)) + goto out_unlock; + + do_for_each_ftrace_rec(pg, rec) { - if (!ftrace_match_record(rec, search, len, type)) + if (!ftrace_match_record(rec, NULL, search, len, type)) continue; entry = kmalloc(sizeof(*entry), GFP_KERNEL); @@ -2196,18 +2727,22 @@ int unregister_ftrace_command(struct ftrace_func_command *cmd) return ret; } -static int ftrace_process_regex(char *buff, int len, int enable) +static int ftrace_process_regex(struct ftrace_hash *hash, + char *buff, int len, int enable) { char *func, *command, *next = buff; struct ftrace_func_command *p; - int ret = -EINVAL; + int ret; func = strsep(&next, ":"); if (!next) { - if (ftrace_match_records(func, len, enable)) - return 0; - return ret; + ret = ftrace_match_records(hash, func, len); + if (!ret) + ret = -EINVAL; + if (ret < 0) + return ret; + return 0; } /* command found */ @@ -2240,6 +2775,10 @@ ftrace_regex_write(struct file *file, const char __user *ubuf, mutex_lock(&ftrace_regex_lock); + ret = -ENODEV; + if (unlikely(ftrace_disabled)) + goto out_unlock; + if (file->f_mode & FMODE_READ) { struct seq_file *m = file->private_data; iter = m->private; @@ -2251,7 +2790,7 @@ ftrace_regex_write(struct file *file, const char __user *ubuf, if (read >= 0 && trace_parser_loaded(parser) && !trace_parser_cont(parser)) { - ret = ftrace_process_regex(parser->buffer, + ret = ftrace_process_regex(iter->hash, parser->buffer, parser->idx, enable); trace_parser_clear(parser); if (ret) @@ -2279,22 +2818,83 @@ ftrace_notrace_write(struct file *file, const char __user *ubuf, return ftrace_regex_write(file, ubuf, cnt, ppos, 0); } -static void -ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) +static int +ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, + int reset, int enable) { + struct ftrace_hash **orig_hash; + struct ftrace_hash *hash; + int ret; + + /* All global ops uses the global ops filters */ + if (ops->flags & FTRACE_OPS_FL_GLOBAL) + ops = &global_ops; + if (unlikely(ftrace_disabled)) - return; + return -ENODEV; + + if (enable) + orig_hash = &ops->filter_hash; + else + orig_hash = &ops->notrace_hash; + + hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); + if (!hash) + return -ENOMEM; mutex_lock(&ftrace_regex_lock); if (reset) - ftrace_filter_reset(enable); + ftrace_filter_reset(hash); if (buf) - ftrace_match_records(buf, len, enable); + ftrace_match_records(hash, buf, len); + + mutex_lock(&ftrace_lock); + ret = ftrace_hash_move(orig_hash, hash); + mutex_unlock(&ftrace_lock); + mutex_unlock(&ftrace_regex_lock); + + free_ftrace_hash(hash); + return ret; +} + +/** + * ftrace_set_filter - set a function to filter on in ftrace + * @ops - the ops to set the filter with + * @buf - the string that holds the function filter text. + * @len - the length of the string. + * @reset - non zero to reset all filters before applying this filter. + * + * Filters denote which functions should be enabled when tracing is enabled. + * If @buf is NULL and reset is set, all functions will be enabled for tracing. + */ +void ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset) +{ + ftrace_set_regex(ops, buf, len, reset, 1); } +EXPORT_SYMBOL_GPL(ftrace_set_filter); /** + * ftrace_set_notrace - set a function to not trace in ftrace + * @ops - the ops to set the notrace filter with + * @buf - the string that holds the function notrace text. + * @len - the length of the string. + * @reset - non zero to reset all filters before applying this filter. + * + * Notrace Filters denote which functions should not be enabled when tracing + * is enabled. If @buf is NULL and reset is set, all functions will be enabled + * for tracing. + */ +void ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, + int len, int reset) +{ + ftrace_set_regex(ops, buf, len, reset, 0); +} +EXPORT_SYMBOL_GPL(ftrace_set_notrace); +/** * ftrace_set_filter - set a function to filter on in ftrace + * @ops - the ops to set the filter with * @buf - the string that holds the function filter text. * @len - the length of the string. * @reset - non zero to reset all filters before applying this filter. @@ -2302,13 +2902,15 @@ ftrace_set_regex(unsigned char *buf, int len, int reset, int enable) * Filters denote which functions should be enabled when tracing is enabled. * If @buf is NULL and reset is set, all functions will be enabled for tracing. */ -void ftrace_set_filter(unsigned char *buf, int len, int reset) +void ftrace_set_global_filter(unsigned char *buf, int len, int reset) { - ftrace_set_regex(buf, len, reset, 1); + ftrace_set_regex(&global_ops, buf, len, reset, 1); } +EXPORT_SYMBOL_GPL(ftrace_set_global_filter); /** * ftrace_set_notrace - set a function to not trace in ftrace + * @ops - the ops to set the notrace filter with * @buf - the string that holds the function notrace text. * @len - the length of the string. * @reset - non zero to reset all filters before applying this filter. @@ -2317,10 +2919,11 @@ void ftrace_set_filter(unsigned char *buf, int len, int reset) * is enabled. If @buf is NULL and reset is set, all functions will be enabled * for tracing. */ -void ftrace_set_notrace(unsigned char *buf, int len, int reset) +void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) { - ftrace_set_regex(buf, len, reset, 0); + ftrace_set_regex(&global_ops, buf, len, reset, 0); } +EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); /* * command line interface to allow users to set filters on boot up. @@ -2371,22 +2974,23 @@ static void __init set_ftrace_early_graph(char *buf) } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -static void __init set_ftrace_early_filter(char *buf, int enable) +static void __init +set_ftrace_early_filter(struct ftrace_ops *ops, char *buf, int enable) { char *func; while (buf) { func = strsep(&buf, ","); - ftrace_set_regex(func, strlen(func), 0, enable); + ftrace_set_regex(ops, func, strlen(func), 0, enable); } } static void __init set_ftrace_early_filters(void) { if (ftrace_filter_buf[0]) - set_ftrace_early_filter(ftrace_filter_buf, 1); + set_ftrace_early_filter(&global_ops, ftrace_filter_buf, 1); if (ftrace_notrace_buf[0]) - set_ftrace_early_filter(ftrace_notrace_buf, 0); + set_ftrace_early_filter(&global_ops, ftrace_notrace_buf, 0); #ifdef CONFIG_FUNCTION_GRAPH_TRACER if (ftrace_graph_buf[0]) set_ftrace_early_graph(ftrace_graph_buf); @@ -2394,11 +2998,14 @@ static void __init set_ftrace_early_filters(void) } static int -ftrace_regex_release(struct inode *inode, struct file *file, int enable) +ftrace_regex_release(struct inode *inode, struct file *file) { struct seq_file *m = (struct seq_file *)file->private_data; struct ftrace_iterator *iter; + struct ftrace_hash **orig_hash; struct trace_parser *parser; + int filter_hash; + int ret; mutex_lock(&ftrace_regex_lock); if (file->f_mode & FMODE_READ) { @@ -2411,33 +3018,41 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable) parser = &iter->parser; if (trace_parser_loaded(parser)) { parser->buffer[parser->idx] = 0; - ftrace_match_records(parser->buffer, parser->idx, enable); + ftrace_match_records(iter->hash, parser->buffer, parser->idx); } - mutex_lock(&ftrace_lock); - if (ftrace_start_up && ftrace_enabled) - ftrace_run_update_code(FTRACE_ENABLE_CALLS); - mutex_unlock(&ftrace_lock); - trace_parser_put(parser); + + if (file->f_mode & FMODE_WRITE) { + filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); + + if (filter_hash) + orig_hash = &iter->ops->filter_hash; + else + orig_hash = &iter->ops->notrace_hash; + + mutex_lock(&ftrace_lock); + /* + * Remove the current set, update the hash and add + * them back. + */ + ftrace_hash_rec_disable(iter->ops, filter_hash); + ret = ftrace_hash_move(orig_hash, iter->hash); + if (!ret) { + ftrace_hash_rec_enable(iter->ops, filter_hash); + if (iter->ops->flags & FTRACE_OPS_FL_ENABLED + && ftrace_enabled) + ftrace_run_update_code(FTRACE_ENABLE_CALLS); + } + mutex_unlock(&ftrace_lock); + } + free_ftrace_hash(iter->hash); kfree(iter); mutex_unlock(&ftrace_regex_lock); return 0; } -static int -ftrace_filter_release(struct inode *inode, struct file *file) -{ - return ftrace_regex_release(inode, file, 1); -} - -static int -ftrace_notrace_release(struct inode *inode, struct file *file) -{ - return ftrace_regex_release(inode, file, 0); -} - static const struct file_operations ftrace_avail_fops = { .open = ftrace_avail_open, .read = seq_read, @@ -2445,8 +3060,8 @@ static const struct file_operations ftrace_avail_fops = { .release = seq_release_private, }; -static const struct file_operations ftrace_failures_fops = { - .open = ftrace_failures_open, +static const struct file_operations ftrace_enabled_fops = { + .open = ftrace_enabled_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release_private, @@ -2457,7 +3072,7 @@ static const struct file_operations ftrace_filter_fops = { .read = seq_read, .write = ftrace_filter_write, .llseek = ftrace_regex_lseek, - .release = ftrace_filter_release, + .release = ftrace_regex_release, }; static const struct file_operations ftrace_notrace_fops = { @@ -2465,7 +3080,7 @@ static const struct file_operations ftrace_notrace_fops = { .read = seq_read, .write = ftrace_notrace_write, .llseek = ftrace_regex_lseek, - .release = ftrace_notrace_release, + .release = ftrace_regex_release, }; #ifdef CONFIG_FUNCTION_GRAPH_TRACER @@ -2574,9 +3189,6 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer) bool exists; int i; - if (ftrace_disabled) - return -ENODEV; - /* decode regex */ type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); if (!not && *idx >= FTRACE_GRAPH_MAX_FUNCS) @@ -2585,12 +3197,18 @@ ftrace_set_func(unsigned long *array, int *idx, char *buffer) search_len = strlen(search); mutex_lock(&ftrace_lock); + + if (unlikely(ftrace_disabled)) { + mutex_unlock(&ftrace_lock); + return -ENODEV; + } + do_for_each_ftrace_rec(pg, rec) { - if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE)) + if (rec->flags & FTRACE_FL_FREE) continue; - if (ftrace_match_record(rec, search, search_len, type)) { + if (ftrace_match_record(rec, NULL, search, search_len, type)) { /* if it is in the array */ exists = false; for (i = 0; i < *idx; i++) { @@ -2680,8 +3298,8 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) trace_create_file("available_filter_functions", 0444, d_tracer, NULL, &ftrace_avail_fops); - trace_create_file("failures", 0444, - d_tracer, NULL, &ftrace_failures_fops); + trace_create_file("enabled_functions", 0444, + d_tracer, NULL, &ftrace_enabled_fops); trace_create_file("set_ftrace_filter", 0644, d_tracer, NULL, &ftrace_filter_fops); @@ -2704,7 +3322,6 @@ static int ftrace_process_locs(struct module *mod, { unsigned long *p; unsigned long addr; - unsigned long flags; mutex_lock(&ftrace_lock); p = start; @@ -2721,10 +3338,7 @@ static int ftrace_process_locs(struct module *mod, ftrace_record_ip(addr); } - /* disable interrupts to prevent kstop machine */ - local_irq_save(flags); ftrace_update_code(mod); - local_irq_restore(flags); mutex_unlock(&ftrace_lock); return 0; @@ -2736,10 +3350,11 @@ void ftrace_release_mod(struct module *mod) struct dyn_ftrace *rec; struct ftrace_page *pg; + mutex_lock(&ftrace_lock); + if (ftrace_disabled) - return; + goto out_unlock; - mutex_lock(&ftrace_lock); do_for_each_ftrace_rec(pg, rec) { if (within_module_core(rec->ip, mod)) { /* @@ -2750,6 +3365,7 @@ void ftrace_release_mod(struct module *mod) ftrace_free_rec(rec); } } while_for_each_ftrace_rec(); + out_unlock: mutex_unlock(&ftrace_lock); } @@ -2836,6 +3452,10 @@ void __init ftrace_init(void) #else +static struct ftrace_ops global_ops = { + .func = ftrace_stub, +}; + static int __init ftrace_nodyn_init(void) { ftrace_enabled = 1; @@ -2846,12 +3466,38 @@ device_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } /* Keep as macros so we do not need to define the commands */ -# define ftrace_startup(command) do { } while (0) -# define ftrace_shutdown(command) do { } while (0) +# define ftrace_startup(ops, command) do { } while (0) +# define ftrace_shutdown(ops, command) do { } while (0) # define ftrace_startup_sysctl() do { } while (0) # define ftrace_shutdown_sysctl() do { } while (0) + +static inline int +ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) +{ + return 1; +} + #endif /* CONFIG_DYNAMIC_FTRACE */ +static void +ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip) +{ + struct ftrace_ops *op; + + /* + * Some of the ops may be dynamically allocated, + * they must be freed after a synchronize_sched(). + */ + preempt_disable_notrace(); + op = rcu_dereference_raw(ftrace_ops_list); + while (op != &ftrace_list_end) { + if (ftrace_ops_test(op, ip)) + op->func(ip, parent_ip); + op = rcu_dereference_raw(op->next); + }; + preempt_enable_notrace(); +} + static void clear_ftrace_swapper(void) { struct task_struct *p; @@ -3144,19 +3790,23 @@ void ftrace_kill(void) */ int register_ftrace_function(struct ftrace_ops *ops) { - int ret; - - if (unlikely(ftrace_disabled)) - return -1; + int ret = -1; mutex_lock(&ftrace_lock); + if (unlikely(ftrace_disabled)) + goto out_unlock; + ret = __register_ftrace_function(ops); - ftrace_startup(0); + if (!ret) + ftrace_startup(ops, 0); + + out_unlock: mutex_unlock(&ftrace_lock); return ret; } +EXPORT_SYMBOL_GPL(register_ftrace_function); /** * unregister_ftrace_function - unregister a function for profiling. @@ -3170,25 +3820,27 @@ int unregister_ftrace_function(struct ftrace_ops *ops) mutex_lock(&ftrace_lock); ret = __unregister_ftrace_function(ops); - ftrace_shutdown(0); + if (!ret) + ftrace_shutdown(ops, 0); mutex_unlock(&ftrace_lock); return ret; } +EXPORT_SYMBOL_GPL(unregister_ftrace_function); int ftrace_enable_sysctl(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { - int ret; - - if (unlikely(ftrace_disabled)) - return -ENODEV; + int ret = -ENODEV; mutex_lock(&ftrace_lock); - ret = proc_dointvec(table, write, buffer, lenp, ppos); + if (unlikely(ftrace_disabled)) + goto out; + + ret = proc_dointvec(table, write, buffer, lenp, ppos); if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) goto out; @@ -3200,11 +3852,11 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, ftrace_startup_sysctl(); /* we are starting ftrace again */ - if (ftrace_list != &ftrace_list_end) { - if (ftrace_list->next == &ftrace_list_end) - ftrace_trace_function = ftrace_list->func; + if (ftrace_ops_list != &ftrace_list_end) { + if (ftrace_ops_list->next == &ftrace_list_end) + ftrace_trace_function = ftrace_ops_list->func; else - ftrace_trace_function = ftrace_list_func; + ftrace_trace_function = ftrace_ops_list_func; } } else { @@ -3328,7 +3980,7 @@ static int start_graph_tracing(void) /* The cpu_boot init_task->ret_stack will never be freed */ for_each_online_cpu(cpu) { if (!idle_task(cpu)->ret_stack) - ftrace_graph_init_task(idle_task(cpu)); + ftrace_graph_init_idle_task(idle_task(cpu), cpu); } do { @@ -3393,7 +4045,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, ftrace_graph_return = retfunc; ftrace_graph_entry = entryfunc; - ftrace_startup(FTRACE_START_FUNC_RET); + ftrace_startup(&global_ops, FTRACE_START_FUNC_RET); out: mutex_unlock(&ftrace_lock); @@ -3410,7 +4062,7 @@ void unregister_ftrace_graph(void) ftrace_graph_active--; ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; ftrace_graph_entry = ftrace_graph_entry_stub; - ftrace_shutdown(FTRACE_STOP_FUNC_RET); + ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET); unregister_pm_notifier(&ftrace_suspend_notifier); unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); @@ -3418,6 +4070,49 @@ void unregister_ftrace_graph(void) mutex_unlock(&ftrace_lock); } +static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); + +static void +graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) +{ + atomic_set(&t->tracing_graph_pause, 0); + atomic_set(&t->trace_overrun, 0); + t->ftrace_timestamp = 0; + /* make curr_ret_stack visible before we add the ret_stack */ + smp_wmb(); + t->ret_stack = ret_stack; +} + +/* + * Allocate a return stack for the idle task. May be the first + * time through, or it may be done by CPU hotplug online. + */ +void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) +{ + t->curr_ret_stack = -1; + /* + * The idle task has no parent, it either has its own + * stack or no stack at all. + */ + if (t->ret_stack) + WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); + + if (ftrace_graph_active) { + struct ftrace_ret_stack *ret_stack; + + ret_stack = per_cpu(idle_ret_stack, cpu); + if (!ret_stack) { + ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH + * sizeof(struct ftrace_ret_stack), + GFP_KERNEL); + if (!ret_stack) + return; + per_cpu(idle_ret_stack, cpu) = ret_stack; + } + graph_init_task(t, ret_stack); + } +} + /* Allocate a return stack for newly created task */ void ftrace_graph_init_task(struct task_struct *t) { @@ -3433,12 +4128,7 @@ void ftrace_graph_init_task(struct task_struct *t) GFP_KERNEL); if (!ret_stack) return; - atomic_set(&t->tracing_graph_pause, 0); - atomic_set(&t->trace_overrun, 0); - t->ftrace_timestamp = 0; - /* make curr_ret_stack visable before we add the ret_stack */ - smp_wmb(); - t->ret_stack = ret_stack; + graph_init_task(t, ret_stack); } } diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c index a22582a0616..f55fcf61b22 100644 --- a/kernel/trace/power-traces.c +++ b/kernel/trace/power-traces.c @@ -13,5 +13,8 @@ #define CREATE_TRACE_POINTS #include <trace/events/power.h> -EXPORT_TRACEPOINT_SYMBOL_GPL(power_frequency); +#ifdef EVENT_POWER_TRACING_DEPRECATED +EXPORT_TRACEPOINT_SYMBOL_GPL(power_start); +#endif +EXPORT_TRACEPOINT_SYMBOL_GPL(cpu_idle); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 9ed509a015d..0ef7b4b2a1f 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -5,7 +5,6 @@ */ #include <linux/ring_buffer.h> #include <linux/trace_clock.h> -#include <linux/ftrace_irq.h> #include <linux/spinlock.h> #include <linux/debugfs.h> #include <linux/uaccess.h> @@ -669,7 +668,7 @@ static struct list_head *rb_list_head(struct list_head *list) * the reader page). But if the next page is a header page, * its flags will be non zero. */ -static int inline +static inline int rb_is_head_page(struct ring_buffer_per_cpu *cpu_buffer, struct buffer_page *page, struct list_head *list) { @@ -1429,6 +1428,17 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) } EXPORT_SYMBOL_GPL(ring_buffer_resize); +void ring_buffer_change_overwrite(struct ring_buffer *buffer, int val) +{ + mutex_lock(&buffer->mutex); + if (val) + buffer->flags |= RB_FL_OVERWRITE; + else + buffer->flags &= ~RB_FL_OVERWRITE; + mutex_unlock(&buffer->mutex); +} +EXPORT_SYMBOL_GPL(ring_buffer_change_overwrite); + static inline void * __rb_data_page_index(struct buffer_data_page *bpage, unsigned index) { @@ -1468,7 +1478,7 @@ static inline unsigned long rb_page_entries(struct buffer_page *bpage) return local_read(&bpage->entries) & RB_WRITE_MASK; } -/* Size is determined by what has been commited */ +/* Size is determined by what has been committed */ static inline unsigned rb_page_size(struct buffer_page *bpage) { return rb_page_commit(bpage); @@ -2162,11 +2172,19 @@ rb_reserve_next_event(struct ring_buffer *buffer, if (likely(ts >= cpu_buffer->write_stamp)) { delta = diff; if (unlikely(test_time_stamp(delta))) { + int local_clock_stable = 1; +#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK + local_clock_stable = sched_clock_stable; +#endif WARN_ONCE(delta > (1ULL << 59), - KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n", + KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s", (unsigned long long)delta, (unsigned long long)ts, - (unsigned long long)cpu_buffer->write_stamp); + (unsigned long long)cpu_buffer->write_stamp, + local_clock_stable ? "" : + "If you just came from a suspend/resume,\n" + "please switch to the trace global clock:\n" + " echo global > /sys/kernel/debug/tracing/trace_clock\n"); add_timestamp = 1; } } @@ -2914,7 +2932,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) /* * cpu_buffer->pages just needs to point to the buffer, it * has no specific buffer page to point to. Lets move it out - * of our way so we don't accidently swap it. + * of our way so we don't accidentally swap it. */ cpu_buffer->pages = reader->list.prev; @@ -3853,6 +3871,13 @@ int ring_buffer_read_page(struct ring_buffer *buffer, /* Need to copy one event at a time */ do { + /* We need the size of one event, because + * rb_advance_reader only advances by one event, + * whereas rb_event_ts_length may include the size of + * one or two events. + * We have already ensured there's enough space if this + * is a time extend. */ + size = rb_event_length(event); memcpy(bpage->data + pos, rpage->data + rpos, size); len -= size; @@ -3867,7 +3892,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer, event = rb_reader_event(cpu_buffer); /* Always keep the time extend and data together */ size = rb_event_ts_length(event); - } while (len > size); + } while (len >= size); /* update bpage */ local_set(&bpage->commit, pos); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 82d9b8106cd..ee9c921d7f2 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -17,7 +17,6 @@ #include <linux/writeback.h> #include <linux/kallsyms.h> #include <linux/seq_file.h> -#include <linux/smp_lock.h> #include <linux/notifier.h> #include <linux/irqflags.h> #include <linux/debugfs.h> @@ -42,8 +41,6 @@ #include "trace.h" #include "trace_output.h" -#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) - /* * On boot up, the ring buffer is set to the minimum size, so that * we do not waste memory on systems that are not using tracing. @@ -341,7 +338,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait); /* trace_flags holds trace_options default values */ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | - TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD; + TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE; static int trace_stop_count; static DEFINE_SPINLOCK(tracing_start_lock); @@ -426,6 +423,7 @@ static const char *trace_options[] = { "sleep-time", "graph-time", "record-cmd", + "overwrite", NULL }; @@ -781,6 +779,11 @@ __acquires(kernel_lock) tracing_reset_online_cpus(tr); current_trace = type; + + /* If we expanded the buffers, make sure the max is expanded too */ + if (ring_buffer_expanded && type->use_max_tr) + ring_buffer_resize(max_tr.buffer, trace_buf_size); + /* the test is responsible for initializing and enabling */ pr_info("Testing tracer %s: ", type->name); ret = type->selftest(type, tr); @@ -793,6 +796,10 @@ __acquires(kernel_lock) /* Only reset on passing, to avoid touching corrupted buffers */ tracing_reset_online_cpus(tr); + /* Shrink the max buffer again */ + if (ring_buffer_expanded && type->use_max_tr) + ring_buffer_resize(max_tr.buffer, 1); + printk(KERN_CONT "PASSED\n"); } #endif @@ -1103,7 +1110,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; - entry->lock_depth = (tsk) ? tsk->lock_depth : 0; + entry->padding = 0; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | @@ -1284,6 +1291,8 @@ void trace_dump_stack(void) __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); } +static DEFINE_PER_CPU(int, user_stack_count); + void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { @@ -1302,10 +1311,20 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) if (unlikely(in_nmi())) return; + /* + * prevent recursion, since the user stack tracing may + * trigger other kernel events. + */ + preempt_disable(); + if (__this_cpu_read(user_stack_count)) + goto out; + + __this_cpu_inc(user_stack_count); + event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, sizeof(*entry), flags, pc); if (!event) - return; + goto out_drop_count; entry = ring_buffer_event_data(event); entry->tgid = current->tgid; @@ -1319,6 +1338,11 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) save_stack_trace_user(&trace); if (!filter_check_discard(call, entry, buffer, event)) ring_buffer_unlock_commit(buffer, event); + + out_drop_count: + __this_cpu_dec(user_stack_count); + out: + preempt_enable(); } #ifdef UNUSED @@ -1733,10 +1757,9 @@ static void print_lat_help_header(struct seq_file *m) seq_puts(m, "# | / _----=> need-resched \n"); seq_puts(m, "# || / _---=> hardirq/softirq \n"); seq_puts(m, "# ||| / _--=> preempt-depth \n"); - seq_puts(m, "# |||| /_--=> lock-depth \n"); - seq_puts(m, "# |||||/ delay \n"); - seq_puts(m, "# cmd pid |||||| time | caller \n"); - seq_puts(m, "# \\ / |||||| \\ | / \n"); + seq_puts(m, "# |||| / delay \n"); + seq_puts(m, "# cmd pid ||||| time | caller \n"); + seq_puts(m, "# \\ / ||||| \\ | / \n"); } static void print_func_help_header(struct seq_file *m) @@ -1991,9 +2014,10 @@ enum print_line_t print_trace_line(struct trace_iterator *iter) { enum print_line_t ret; - if (iter->lost_events) - trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", - iter->cpu, iter->lost_events); + if (iter->lost_events && + !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", + iter->cpu, iter->lost_events)) + return TRACE_TYPE_PARTIAL_LINE; if (iter->trace && iter->trace->print_line) { ret = iter->trace->print_line(iter); @@ -2320,11 +2344,19 @@ tracing_write_stub(struct file *filp, const char __user *ubuf, return count; } +static loff_t tracing_seek(struct file *file, loff_t offset, int origin) +{ + if (file->f_mode & FMODE_READ) + return seq_lseek(file, offset, origin); + else + return 0; +} + static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, .write = tracing_write_stub, - .llseek = seq_lseek, + .llseek = tracing_seek, .release = tracing_release, }; @@ -2505,6 +2537,9 @@ static void set_tracer_flags(unsigned int mask, int enabled) if (mask == TRACE_ITER_RECORD_CMD) trace_event_enable_cmd_record(enabled); + + if (mask == TRACE_ITER_OVERWRITE) + ring_buffer_change_overwrite(global_trace.buffer, enabled); } static ssize_t @@ -2686,6 +2721,10 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf, mutex_lock(&trace_types_lock); if (tracer_enabled ^ val) { + + /* Only need to warn if this is used to change the state */ + WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); + if (val) { tracer_enabled = 1; if (current_trace->start) @@ -3192,6 +3231,14 @@ waitagain: if (iter->seq.len >= cnt) break; + + /* + * Setting the full flag means we reached the trace_seq buffer + * size and we should leave by partial output condition above. + * One of the trace_seq_* functions is not used properly. + */ + WARN_ONCE(iter->seq.full, "full flag set for trace type %d", + iter->ent->type); } trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); @@ -3202,7 +3249,7 @@ waitagain: trace_seq_init(&iter->seq); /* - * If there was nothing to send to user, inspite of consuming trace + * If there was nothing to send to user, in spite of consuming trace * entries, go back to wait for more entries. */ if (sret == -EBUSY) @@ -4527,9 +4574,11 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) __init static int tracer_alloc_buffers(void) { int ring_buf_size; + enum ring_buffer_flags rb_flags; int i; int ret = -ENOMEM; + if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; @@ -4542,12 +4591,13 @@ __init static int tracer_alloc_buffers(void) else ring_buf_size = 1; + rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + cpumask_copy(tracing_buffer_mask, cpu_possible_mask); cpumask_copy(tracing_cpumask, cpu_all_mask); /* TODO: make the number of buffers hot pluggable with CPUS */ - global_trace.buffer = ring_buffer_alloc(ring_buf_size, - TRACE_BUFFER_FLAGS); + global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); if (!global_trace.buffer) { printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); WARN_ON(1); @@ -4557,7 +4607,7 @@ __init static int tracer_alloc_buffers(void) #ifdef CONFIG_TRACER_MAX_TRACE - max_tr.buffer = ring_buffer_alloc(1, TRACE_BUFFER_FLAGS); + max_tr.buffer = ring_buffer_alloc(1, rb_flags); if (!max_tr.buffer) { printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); WARN_ON(1); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 9021f8c0c0c..6b69c4bd306 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -272,8 +272,8 @@ struct tracer { /* If you handled the flag setting, return 0 */ int (*set_flag)(u32 old_flags, u32 bit, int set); struct tracer *next; - int print_max; struct tracer_flags *flags; + int print_max; int use_max_tr; }; @@ -419,6 +419,8 @@ extern void trace_find_cmdline(int pid, char comm[]); extern unsigned long ftrace_update_tot_cnt; #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func extern int DYN_FTRACE_TEST_NAME(void); +#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 +extern int DYN_FTRACE_TEST_NAME2(void); #endif extern int ring_buffer_expanded; @@ -606,6 +608,7 @@ enum trace_iterator_flags { TRACE_ITER_SLEEP_TIME = 0x40000, TRACE_ITER_GRAPH_TIME = 0x80000, TRACE_ITER_RECORD_CMD = 0x100000, + TRACE_ITER_OVERWRITE = 0x200000, }; /* @@ -661,8 +664,10 @@ struct ftrace_event_field { }; struct event_filter { - int n_preds; - struct filter_pred **preds; + int n_preds; /* Number assigned */ + int a_preds; /* allocated */ + struct filter_pred *preds; + struct filter_pred *root; char *filter_string; }; @@ -674,11 +679,23 @@ struct event_subsystem { int nr_events; }; +#define FILTER_PRED_INVALID ((unsigned short)-1) +#define FILTER_PRED_IS_RIGHT (1 << 15) +#define FILTER_PRED_FOLD (1 << 15) + +/* + * The max preds is the size of unsigned short with + * two flags at the MSBs. One bit is used for both the IS_RIGHT + * and FOLD flags. The other is reserved. + * + * 2^14 preds is way more than enough. + */ +#define MAX_FILTER_PRED 16384 + struct filter_pred; struct regex; -typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event, - int val1, int val2); +typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event); typedef int (*regex_match_func)(char *str, struct regex *r, int len); @@ -700,11 +717,23 @@ struct filter_pred { filter_pred_fn_t fn; u64 val; struct regex regex; - char *field_name; + /* + * Leaf nodes use field_name, ops is used by AND and OR + * nodes. The field_name is always freed when freeing a pred. + * We can overload field_name for ops and have it freed + * as well. + */ + union { + char *field_name; + unsigned short *ops; + }; int offset; int not; int op; - int pop_n; + unsigned short index; + unsigned short parent; + unsigned short left; + unsigned short right; }; extern struct list_head ftrace_common_fields; diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c index 685a67d55db..6302747a139 100644 --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -46,7 +46,7 @@ u64 notrace trace_clock_local(void) } /* - * trace_clock(): 'inbetween' trace clock. Not completely serialized, + * trace_clock(): 'between' trace clock. Not completely serialized, * but not completely incorrect when crossing CPUs either. * * This is based on cpu_clock(), which will allow at most ~1 jiffy of diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index e3dfecaf13e..e32744c84d9 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -27,7 +27,7 @@ * in the structure. * * * for structures within structures, the format of the internal - * structure is layed out. This allows the internal structure + * structure is laid out. This allows the internal structure * to be deciphered for the format file. Although these macros * may become out of sync with the internal structure, they * will create a compile error if it happens. Since the @@ -53,7 +53,7 @@ */ /* - * Function trace entry - function address and parent function addres: + * Function trace entry - function address and parent function address: */ FTRACE_ENTRY(function, ftrace_entry, @@ -109,12 +109,12 @@ FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry, */ #define FTRACE_CTX_FIELDS \ __field( unsigned int, prev_pid ) \ + __field( unsigned int, next_pid ) \ + __field( unsigned int, next_cpu ) \ __field( unsigned char, prev_prio ) \ __field( unsigned char, prev_state ) \ - __field( unsigned int, next_pid ) \ __field( unsigned char, next_prio ) \ - __field( unsigned char, next_state ) \ - __field( unsigned int, next_cpu ) + __field( unsigned char, next_state ) FTRACE_ENTRY(context_switch, ctx_switch_entry, diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 39c059ca670..19a359d5e6d 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -21,17 +21,46 @@ typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / sizeof(unsigned long)]) /* Count the events in use (per event id, not per instance) */ static int total_ref_count; +static int perf_trace_event_perm(struct ftrace_event_call *tp_event, + struct perf_event *p_event) +{ + /* No tracing, just counting, so no obvious leak */ + if (!(p_event->attr.sample_type & PERF_SAMPLE_RAW)) + return 0; + + /* Some events are ok to be traced by non-root users... */ + if (p_event->attach_state == PERF_ATTACH_TASK) { + if (tp_event->flags & TRACE_EVENT_FL_CAP_ANY) + return 0; + } + + /* + * ...otherwise raw tracepoint data can be a severe data leak, + * only allow root to have these. + */ + if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + return 0; +} + static int perf_trace_event_init(struct ftrace_event_call *tp_event, struct perf_event *p_event) { struct hlist_head __percpu *list; - int ret = -ENOMEM; + int ret; int cpu; + ret = perf_trace_event_perm(tp_event, p_event); + if (ret) + return ret; + p_event->tp_event = tp_event; if (tp_event->perf_refcount++ > 0) return 0; + ret = -ENOMEM; + list = alloc_percpu(struct hlist_head); if (!list) goto fail; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 0725eeab193..2fe11034135 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,6 +27,12 @@ DEFINE_MUTEX(event_mutex); +DEFINE_MUTEX(event_storage_mutex); +EXPORT_SYMBOL_GPL(event_storage_mutex); + +char event_storage[EVENT_STORAGE_SIZE]; +EXPORT_SYMBOL_GPL(event_storage); + LIST_HEAD(ftrace_events); LIST_HEAD(ftrace_common_fields); @@ -110,7 +116,7 @@ static int trace_define_common_fields(void) __common_field(unsigned char, flags); __common_field(unsigned char, preempt_count); __common_field(int, pid); - __common_field(int, lock_depth); + __common_field(int, padding); return ret; } @@ -320,6 +326,7 @@ int trace_set_clr_event(const char *system, const char *event, int set) { return __ftrace_set_clr_event(NULL, system, event, set); } +EXPORT_SYMBOL_GPL(trace_set_clr_event); /* 128 should be much more than enough */ #define EVENT_BUF_SIZE 127 @@ -1278,7 +1285,7 @@ trace_create_file_ops(struct module *mod) static void trace_module_add_events(struct module *mod) { struct ftrace_module_file_ops *file_ops = NULL; - struct ftrace_event_call *call, *start, *end; + struct ftrace_event_call **call, **start, **end; start = mod->trace_events; end = mod->trace_events + mod->num_trace_events; @@ -1291,7 +1298,7 @@ static void trace_module_add_events(struct module *mod) return; for_each_event(call, start, end) { - __trace_add_event_call(call, mod, + __trace_add_event_call(*call, mod, &file_ops->id, &file_ops->enable, &file_ops->filter, &file_ops->format); } @@ -1361,8 +1368,8 @@ static struct notifier_block trace_module_nb = { .priority = 0, }; -extern struct ftrace_event_call __start_ftrace_events[]; -extern struct ftrace_event_call __stop_ftrace_events[]; +extern struct ftrace_event_call *__start_ftrace_events[]; +extern struct ftrace_event_call *__stop_ftrace_events[]; static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; @@ -1378,7 +1385,7 @@ __setup("trace_event=", setup_trace_event); static __init int event_trace_init(void) { - struct ftrace_event_call *call; + struct ftrace_event_call **call; struct dentry *d_tracer; struct dentry *entry; struct dentry *d_events; @@ -1424,7 +1431,7 @@ static __init int event_trace_init(void) pr_warning("tracing: Failed to allocate common fields"); for_each_event(call, __start_ftrace_events, __stop_ftrace_events) { - __trace_add_event_call(call, NULL, &ftrace_event_id_fops, + __trace_add_event_call(*call, NULL, &ftrace_event_id_fops, &ftrace_enable_fops, &ftrace_event_filter_fops, &ftrace_event_format_fops); diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 36d40104b17..8008ddcfbf2 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -123,9 +123,13 @@ struct filter_parse_state { } operand; }; +struct pred_stack { + struct filter_pred **preds; + int index; +}; + #define DEFINE_COMPARISON_PRED(type) \ -static int filter_pred_##type(struct filter_pred *pred, void *event, \ - int val1, int val2) \ +static int filter_pred_##type(struct filter_pred *pred, void *event) \ { \ type *addr = (type *)(event + pred->offset); \ type val = (type)pred->val; \ @@ -152,8 +156,7 @@ static int filter_pred_##type(struct filter_pred *pred, void *event, \ } #define DEFINE_EQUALITY_PRED(size) \ -static int filter_pred_##size(struct filter_pred *pred, void *event, \ - int val1, int val2) \ +static int filter_pred_##size(struct filter_pred *pred, void *event) \ { \ u##size *addr = (u##size *)(event + pred->offset); \ u##size val = (u##size)pred->val; \ @@ -178,23 +181,8 @@ DEFINE_EQUALITY_PRED(32); DEFINE_EQUALITY_PRED(16); DEFINE_EQUALITY_PRED(8); -static int filter_pred_and(struct filter_pred *pred __attribute((unused)), - void *event __attribute((unused)), - int val1, int val2) -{ - return val1 && val2; -} - -static int filter_pred_or(struct filter_pred *pred __attribute((unused)), - void *event __attribute((unused)), - int val1, int val2) -{ - return val1 || val2; -} - /* Filter predicate for fixed sized arrays of characters */ -static int filter_pred_string(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_string(struct filter_pred *pred, void *event) { char *addr = (char *)(event + pred->offset); int cmp, match; @@ -207,8 +195,7 @@ static int filter_pred_string(struct filter_pred *pred, void *event, } /* Filter predicate for char * pointers */ -static int filter_pred_pchar(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_pchar(struct filter_pred *pred, void *event) { char **addr = (char **)(event + pred->offset); int cmp, match; @@ -231,8 +218,7 @@ static int filter_pred_pchar(struct filter_pred *pred, void *event, * and add it to the address of the entry, and at last we have * the address of the string. */ -static int filter_pred_strloc(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_strloc(struct filter_pred *pred, void *event) { u32 str_item = *(u32 *)(event + pred->offset); int str_loc = str_item & 0xffff; @@ -247,8 +233,7 @@ static int filter_pred_strloc(struct filter_pred *pred, void *event, return match; } -static int filter_pred_none(struct filter_pred *pred, void *event, - int val1, int val2) +static int filter_pred_none(struct filter_pred *pred, void *event) { return 0; } @@ -377,32 +362,147 @@ static void filter_build_regex(struct filter_pred *pred) pred->not ^= not; } +enum move_type { + MOVE_DOWN, + MOVE_UP_FROM_LEFT, + MOVE_UP_FROM_RIGHT +}; + +static struct filter_pred * +get_pred_parent(struct filter_pred *pred, struct filter_pred *preds, + int index, enum move_type *move) +{ + if (pred->parent & FILTER_PRED_IS_RIGHT) + *move = MOVE_UP_FROM_RIGHT; + else + *move = MOVE_UP_FROM_LEFT; + pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT]; + + return pred; +} + +/* + * A series of AND or ORs where found together. Instead of + * climbing up and down the tree branches, an array of the + * ops were made in order of checks. We can just move across + * the array and short circuit if needed. + */ +static int process_ops(struct filter_pred *preds, + struct filter_pred *op, void *rec) +{ + struct filter_pred *pred; + int match = 0; + int type; + int i; + + /* + * Micro-optimization: We set type to true if op + * is an OR and false otherwise (AND). Then we + * just need to test if the match is equal to + * the type, and if it is, we can short circuit the + * rest of the checks: + * + * if ((match && op->op == OP_OR) || + * (!match && op->op == OP_AND)) + * return match; + */ + type = op->op == OP_OR; + + for (i = 0; i < op->val; i++) { + pred = &preds[op->ops[i]]; + match = pred->fn(pred, rec); + if (!!match == type) + return match; + } + return match; +} + /* return 1 if event matches, 0 otherwise (discard) */ int filter_match_preds(struct event_filter *filter, void *rec) { - int match, top = 0, val1 = 0, val2 = 0; - int stack[MAX_FILTER_PRED]; + int match = -1; + enum move_type move = MOVE_DOWN; + struct filter_pred *preds; struct filter_pred *pred; - int i; + struct filter_pred *root; + int n_preds; + int done = 0; + + /* no filter is considered a match */ + if (!filter) + return 1; + + n_preds = filter->n_preds; + + if (!n_preds) + return 1; + + /* + * n_preds, root and filter->preds are protect with preemption disabled. + */ + preds = rcu_dereference_sched(filter->preds); + root = rcu_dereference_sched(filter->root); + if (!root) + return 1; + + pred = root; - for (i = 0; i < filter->n_preds; i++) { - pred = filter->preds[i]; - if (!pred->pop_n) { - match = pred->fn(pred, rec, val1, val2); - stack[top++] = match; + /* match is currently meaningless */ + match = -1; + + do { + switch (move) { + case MOVE_DOWN: + /* only AND and OR have children */ + if (pred->left != FILTER_PRED_INVALID) { + /* If ops is set, then it was folded. */ + if (!pred->ops) { + /* keep going to down the left side */ + pred = &preds[pred->left]; + continue; + } + /* We can treat folded ops as a leaf node */ + match = process_ops(preds, pred, rec); + } else + match = pred->fn(pred, rec); + /* If this pred is the only pred */ + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + case MOVE_UP_FROM_LEFT: + /* + * Check for short circuits. + * + * Optimization: !!match == (pred->op == OP_OR) + * is the same as: + * if ((match && pred->op == OP_OR) || + * (!match && pred->op == OP_AND)) + */ + if (!!match == (pred->op == OP_OR)) { + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + } + /* now go down the right side of the tree. */ + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + /* We finished this equation. */ + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); continue; } - if (pred->pop_n > top) { - WARN_ON_ONCE(1); - return 0; - } - val1 = stack[--top]; - val2 = stack[--top]; - match = pred->fn(pred, rec, val1, val2); - stack[top++] = match; - } + done = 1; + } while (!done); - return stack[--top]; + return match; } EXPORT_SYMBOL_GPL(filter_match_preds); @@ -414,6 +514,9 @@ static void parse_error(struct filter_parse_state *ps, int err, int pos) static void remove_filter_string(struct event_filter *filter) { + if (!filter) + return; + kfree(filter->filter_string); filter->filter_string = NULL; } @@ -473,9 +576,10 @@ static void append_filter_err(struct filter_parse_state *ps, void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) { - struct event_filter *filter = call->filter; + struct event_filter *filter; mutex_lock(&event_mutex); + filter = call->filter; if (filter && filter->filter_string) trace_seq_printf(s, "%s\n", filter->filter_string); else @@ -486,9 +590,10 @@ void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) void print_subsystem_event_filter(struct event_subsystem *system, struct trace_seq *s) { - struct event_filter *filter = system->filter; + struct event_filter *filter; mutex_lock(&event_mutex); + filter = system->filter; if (filter && filter->filter_string) trace_seq_printf(s, "%s\n", filter->filter_string); else @@ -539,10 +644,58 @@ static void filter_clear_pred(struct filter_pred *pred) pred->regex.len = 0; } -static int filter_set_pred(struct filter_pred *dest, +static int __alloc_pred_stack(struct pred_stack *stack, int n_preds) +{ + stack->preds = kzalloc(sizeof(*stack->preds)*(n_preds + 1), GFP_KERNEL); + if (!stack->preds) + return -ENOMEM; + stack->index = n_preds; + return 0; +} + +static void __free_pred_stack(struct pred_stack *stack) +{ + kfree(stack->preds); + stack->index = 0; +} + +static int __push_pred_stack(struct pred_stack *stack, + struct filter_pred *pred) +{ + int index = stack->index; + + if (WARN_ON(index == 0)) + return -ENOSPC; + + stack->preds[--index] = pred; + stack->index = index; + return 0; +} + +static struct filter_pred * +__pop_pred_stack(struct pred_stack *stack) +{ + struct filter_pred *pred; + int index = stack->index; + + pred = stack->preds[index++]; + if (!pred) + return NULL; + + stack->index = index; + return pred; +} + +static int filter_set_pred(struct event_filter *filter, + int idx, + struct pred_stack *stack, struct filter_pred *src, filter_pred_fn_t fn) { + struct filter_pred *dest = &filter->preds[idx]; + struct filter_pred *left; + struct filter_pred *right; + *dest = *src; if (src->field_name) { dest->field_name = kstrdup(src->field_name, GFP_KERNEL); @@ -550,116 +703,140 @@ static int filter_set_pred(struct filter_pred *dest, return -ENOMEM; } dest->fn = fn; + dest->index = idx; - return 0; + if (dest->op == OP_OR || dest->op == OP_AND) { + right = __pop_pred_stack(stack); + left = __pop_pred_stack(stack); + if (!left || !right) + return -EINVAL; + /* + * If both children can be folded + * and they are the same op as this op or a leaf, + * then this op can be folded. + */ + if (left->index & FILTER_PRED_FOLD && + (left->op == dest->op || + left->left == FILTER_PRED_INVALID) && + right->index & FILTER_PRED_FOLD && + (right->op == dest->op || + right->left == FILTER_PRED_INVALID)) + dest->index |= FILTER_PRED_FOLD; + + dest->left = left->index & ~FILTER_PRED_FOLD; + dest->right = right->index & ~FILTER_PRED_FOLD; + left->parent = dest->index & ~FILTER_PRED_FOLD; + right->parent = dest->index | FILTER_PRED_IS_RIGHT; + } else { + /* + * Make dest->left invalid to be used as a quick + * way to know this is a leaf node. + */ + dest->left = FILTER_PRED_INVALID; + + /* All leafs allow folding the parent ops. */ + dest->index |= FILTER_PRED_FOLD; + } + + return __push_pred_stack(stack, dest); } -static void filter_disable_preds(struct ftrace_event_call *call) +static void __free_preds(struct event_filter *filter) { - struct event_filter *filter = call->filter; int i; - call->flags &= ~TRACE_EVENT_FL_FILTERED; + if (filter->preds) { + for (i = 0; i < filter->a_preds; i++) + kfree(filter->preds[i].field_name); + kfree(filter->preds); + filter->preds = NULL; + } + filter->a_preds = 0; filter->n_preds = 0; - - for (i = 0; i < MAX_FILTER_PRED; i++) - filter->preds[i]->fn = filter_pred_none; } -static void __free_preds(struct event_filter *filter) +static void filter_disable(struct ftrace_event_call *call) { - int i; + call->flags &= ~TRACE_EVENT_FL_FILTERED; +} +static void __free_filter(struct event_filter *filter) +{ if (!filter) return; - for (i = 0; i < MAX_FILTER_PRED; i++) { - if (filter->preds[i]) - filter_free_pred(filter->preds[i]); - } - kfree(filter->preds); + __free_preds(filter); kfree(filter->filter_string); kfree(filter); } +/* + * Called when destroying the ftrace_event_call. + * The call is being freed, so we do not need to worry about + * the call being currently used. This is for module code removing + * the tracepoints from within it. + */ void destroy_preds(struct ftrace_event_call *call) { - __free_preds(call->filter); + __free_filter(call->filter); call->filter = NULL; - call->flags &= ~TRACE_EVENT_FL_FILTERED; } -static struct event_filter *__alloc_preds(void) +static struct event_filter *__alloc_filter(void) { struct event_filter *filter; + + filter = kzalloc(sizeof(*filter), GFP_KERNEL); + return filter; +} + +static int __alloc_preds(struct event_filter *filter, int n_preds) +{ struct filter_pred *pred; int i; - filter = kzalloc(sizeof(*filter), GFP_KERNEL); - if (!filter) - return ERR_PTR(-ENOMEM); + if (filter->preds) + __free_preds(filter); - filter->n_preds = 0; + filter->preds = + kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL); - filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL); if (!filter->preds) - goto oom; + return -ENOMEM; - for (i = 0; i < MAX_FILTER_PRED; i++) { - pred = kzalloc(sizeof(*pred), GFP_KERNEL); - if (!pred) - goto oom; + filter->a_preds = n_preds; + filter->n_preds = 0; + + for (i = 0; i < n_preds; i++) { + pred = &filter->preds[i]; pred->fn = filter_pred_none; - filter->preds[i] = pred; } - return filter; - -oom: - __free_preds(filter); - return ERR_PTR(-ENOMEM); -} - -static int init_preds(struct ftrace_event_call *call) -{ - if (call->filter) - return 0; - - call->flags &= ~TRACE_EVENT_FL_FILTERED; - call->filter = __alloc_preds(); - if (IS_ERR(call->filter)) - return PTR_ERR(call->filter); - return 0; } -static int init_subsystem_preds(struct event_subsystem *system) +static void filter_free_subsystem_preds(struct event_subsystem *system) { struct ftrace_event_call *call; - int err; list_for_each_entry(call, &ftrace_events, list) { if (strcmp(call->class->system, system->name) != 0) continue; - err = init_preds(call); - if (err) - return err; + filter_disable(call); + remove_filter_string(call->filter); } - - return 0; } -static void filter_free_subsystem_preds(struct event_subsystem *system) +static void filter_free_subsystem_filters(struct event_subsystem *system) { struct ftrace_event_call *call; list_for_each_entry(call, &ftrace_events, list) { if (strcmp(call->class->system, system->name) != 0) continue; - - filter_disable_preds(call); - remove_filter_string(call->filter); + __free_filter(call->filter); + call->filter = NULL; } } @@ -667,18 +844,19 @@ static int filter_add_pred_fn(struct filter_parse_state *ps, struct ftrace_event_call *call, struct event_filter *filter, struct filter_pred *pred, + struct pred_stack *stack, filter_pred_fn_t fn) { int idx, err; - if (filter->n_preds == MAX_FILTER_PRED) { + if (WARN_ON(filter->n_preds == filter->a_preds)) { parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); return -ENOSPC; } idx = filter->n_preds; - filter_clear_pred(filter->preds[idx]); - err = filter_set_pred(filter->preds[idx], pred, fn); + filter_clear_pred(&filter->preds[idx]); + err = filter_set_pred(filter, idx, stack, pred, fn); if (err) return err; @@ -763,6 +941,7 @@ static int filter_add_pred(struct filter_parse_state *ps, struct ftrace_event_call *call, struct event_filter *filter, struct filter_pred *pred, + struct pred_stack *stack, bool dry_run) { struct ftrace_event_field *field; @@ -770,17 +949,12 @@ static int filter_add_pred(struct filter_parse_state *ps, unsigned long long val; int ret; - pred->fn = filter_pred_none; + fn = pred->fn = filter_pred_none; - if (pred->op == OP_AND) { - pred->pop_n = 2; - fn = filter_pred_and; + if (pred->op == OP_AND) goto add_pred_fn; - } else if (pred->op == OP_OR) { - pred->pop_n = 2; - fn = filter_pred_or; + else if (pred->op == OP_OR) goto add_pred_fn; - } field = find_event_field(call, pred->field_name); if (!field) { @@ -829,7 +1003,7 @@ static int filter_add_pred(struct filter_parse_state *ps, add_pred_fn: if (!dry_run) - return filter_add_pred_fn(ps, call, filter, pred, fn); + return filter_add_pred_fn(ps, call, filter, pred, stack, fn); return 0; } @@ -1187,6 +1361,234 @@ static int check_preds(struct filter_parse_state *ps) return 0; } +static int count_preds(struct filter_parse_state *ps) +{ + struct postfix_elt *elt; + int n_preds = 0; + + list_for_each_entry(elt, &ps->postfix, list) { + if (elt->op == OP_NONE) + continue; + n_preds++; + } + + return n_preds; +} + +/* + * The tree is walked at filtering of an event. If the tree is not correctly + * built, it may cause an infinite loop. Check here that the tree does + * indeed terminate. + */ +static int check_pred_tree(struct event_filter *filter, + struct filter_pred *root) +{ + struct filter_pred *preds; + struct filter_pred *pred; + enum move_type move = MOVE_DOWN; + int count = 0; + int done = 0; + int max; + + /* + * The max that we can hit a node is three times. + * Once going down, once coming up from left, and + * once coming up from right. This is more than enough + * since leafs are only hit a single time. + */ + max = 3 * filter->n_preds; + + preds = filter->preds; + if (!preds) + return -EINVAL; + pred = root; + + do { + if (WARN_ON(count++ > max)) + return -EINVAL; + + switch (move) { + case MOVE_DOWN: + if (pred->left != FILTER_PRED_INVALID) { + pred = &preds[pred->left]; + continue; + } + /* A leaf at the root is just a leaf in the tree */ + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + case MOVE_UP_FROM_LEFT: + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + } + done = 1; + } while (!done); + + /* We are fine. */ + return 0; +} + +static int count_leafs(struct filter_pred *preds, struct filter_pred *root) +{ + struct filter_pred *pred; + enum move_type move = MOVE_DOWN; + int count = 0; + int done = 0; + + pred = root; + + do { + switch (move) { + case MOVE_DOWN: + if (pred->left != FILTER_PRED_INVALID) { + pred = &preds[pred->left]; + continue; + } + /* A leaf at the root is just a leaf in the tree */ + if (pred == root) + return 1; + count++; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + case MOVE_UP_FROM_LEFT: + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + } + done = 1; + } while (!done); + + return count; +} + +static int fold_pred(struct filter_pred *preds, struct filter_pred *root) +{ + struct filter_pred *pred; + enum move_type move = MOVE_DOWN; + int count = 0; + int children; + int done = 0; + + /* No need to keep the fold flag */ + root->index &= ~FILTER_PRED_FOLD; + + /* If the root is a leaf then do nothing */ + if (root->left == FILTER_PRED_INVALID) + return 0; + + /* count the children */ + children = count_leafs(preds, &preds[root->left]); + children += count_leafs(preds, &preds[root->right]); + + root->ops = kzalloc(sizeof(*root->ops) * children, GFP_KERNEL); + if (!root->ops) + return -ENOMEM; + + root->val = children; + + pred = root; + do { + switch (move) { + case MOVE_DOWN: + if (pred->left != FILTER_PRED_INVALID) { + pred = &preds[pred->left]; + continue; + } + if (WARN_ON(count == children)) + return -EINVAL; + pred->index &= ~FILTER_PRED_FOLD; + root->ops[count++] = pred->index; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + case MOVE_UP_FROM_LEFT: + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + } + done = 1; + } while (!done); + + return 0; +} + +/* + * To optimize the processing of the ops, if we have several "ors" or + * "ands" together, we can put them in an array and process them all + * together speeding up the filter logic. + */ +static int fold_pred_tree(struct event_filter *filter, + struct filter_pred *root) +{ + struct filter_pred *preds; + struct filter_pred *pred; + enum move_type move = MOVE_DOWN; + int done = 0; + int err; + + preds = filter->preds; + if (!preds) + return -EINVAL; + pred = root; + + do { + switch (move) { + case MOVE_DOWN: + if (pred->index & FILTER_PRED_FOLD) { + err = fold_pred(preds, pred); + if (err) + return err; + /* Folded nodes are like leafs */ + } else if (pred->left != FILTER_PRED_INVALID) { + pred = &preds[pred->left]; + continue; + } + + /* A leaf at the root is just a leaf in the tree */ + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + case MOVE_UP_FROM_LEFT: + pred = &preds[pred->right]; + move = MOVE_DOWN; + continue; + case MOVE_UP_FROM_RIGHT: + if (pred == root) + break; + pred = get_pred_parent(pred, preds, + pred->parent, &move); + continue; + } + done = 1; + } while (!done); + + return 0; +} + static int replace_preds(struct ftrace_event_call *call, struct event_filter *filter, struct filter_parse_state *ps, @@ -1195,14 +1597,32 @@ static int replace_preds(struct ftrace_event_call *call, { char *operand1 = NULL, *operand2 = NULL; struct filter_pred *pred; + struct filter_pred *root; struct postfix_elt *elt; + struct pred_stack stack = { }; /* init to NULL */ int err; int n_preds = 0; + n_preds = count_preds(ps); + if (n_preds >= MAX_FILTER_PRED) { + parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); + return -ENOSPC; + } + err = check_preds(ps); if (err) return err; + if (!dry_run) { + err = __alloc_pred_stack(&stack, n_preds); + if (err) + return err; + err = __alloc_preds(filter, n_preds); + if (err) + goto fail; + } + + n_preds = 0; list_for_each_entry(elt, &ps->postfix, list) { if (elt->op == OP_NONE) { if (!operand1) @@ -1211,14 +1631,16 @@ static int replace_preds(struct ftrace_event_call *call, operand2 = elt->operand; else { parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0); - return -EINVAL; + err = -EINVAL; + goto fail; } continue; } - if (n_preds++ == MAX_FILTER_PRED) { + if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) { parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); - return -ENOSPC; + err = -ENOSPC; + goto fail; } if (elt->op == OP_AND || elt->op == OP_OR) { @@ -1228,76 +1650,181 @@ static int replace_preds(struct ftrace_event_call *call, if (!operand1 || !operand2) { parse_error(ps, FILT_ERR_MISSING_FIELD, 0); - return -EINVAL; + err = -EINVAL; + goto fail; } pred = create_pred(elt->op, operand1, operand2); add_pred: - if (!pred) - return -ENOMEM; - err = filter_add_pred(ps, call, filter, pred, dry_run); + if (!pred) { + err = -ENOMEM; + goto fail; + } + err = filter_add_pred(ps, call, filter, pred, &stack, dry_run); filter_free_pred(pred); if (err) - return err; + goto fail; operand1 = operand2 = NULL; } - return 0; + if (!dry_run) { + /* We should have one item left on the stack */ + pred = __pop_pred_stack(&stack); + if (!pred) + return -EINVAL; + /* This item is where we start from in matching */ + root = pred; + /* Make sure the stack is empty */ + pred = __pop_pred_stack(&stack); + if (WARN_ON(pred)) { + err = -EINVAL; + filter->root = NULL; + goto fail; + } + err = check_pred_tree(filter, root); + if (err) + goto fail; + + /* Optimize the tree */ + err = fold_pred_tree(filter, root); + if (err) + goto fail; + + /* We don't set root until we know it works */ + barrier(); + filter->root = root; + } + + err = 0; +fail: + __free_pred_stack(&stack); + return err; } +struct filter_list { + struct list_head list; + struct event_filter *filter; +}; + static int replace_system_preds(struct event_subsystem *system, struct filter_parse_state *ps, char *filter_string) { struct ftrace_event_call *call; + struct filter_list *filter_item; + struct filter_list *tmp; + LIST_HEAD(filter_list); bool fail = true; int err; list_for_each_entry(call, &ftrace_events, list) { - struct event_filter *filter = call->filter; if (strcmp(call->class->system, system->name) != 0) continue; - /* try to see if the filter can be applied */ - err = replace_preds(call, filter, ps, filter_string, true); + /* + * Try to see if the filter can be applied + * (filter arg is ignored on dry_run) + */ + err = replace_preds(call, NULL, ps, filter_string, true); if (err) + goto fail; + } + + list_for_each_entry(call, &ftrace_events, list) { + struct event_filter *filter; + + if (strcmp(call->class->system, system->name) != 0) continue; - /* really apply the filter */ - filter_disable_preds(call); - err = replace_preds(call, filter, ps, filter_string, false); + filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); + if (!filter_item) + goto fail_mem; + + list_add_tail(&filter_item->list, &filter_list); + + filter_item->filter = __alloc_filter(); + if (!filter_item->filter) + goto fail_mem; + filter = filter_item->filter; + + /* Can only fail on no memory */ + err = replace_filter_string(filter, filter_string); if (err) - filter_disable_preds(call); - else { + goto fail_mem; + + err = replace_preds(call, filter, ps, filter_string, false); + if (err) { + filter_disable(call); + parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); + append_filter_err(ps, filter); + } else call->flags |= TRACE_EVENT_FL_FILTERED; - replace_filter_string(filter, filter_string); - } + /* + * Regardless of if this returned an error, we still + * replace the filter for the call. + */ + filter = call->filter; + call->filter = filter_item->filter; + filter_item->filter = filter; + fail = false; } - if (fail) { - parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); - return -EINVAL; + if (fail) + goto fail; + + /* + * The calls can still be using the old filters. + * Do a synchronize_sched() to ensure all calls are + * done with them before we free them. + */ + synchronize_sched(); + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + __free_filter(filter_item->filter); + list_del(&filter_item->list); + kfree(filter_item); } return 0; + fail: + /* No call succeeded */ + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + list_del(&filter_item->list); + kfree(filter_item); + } + parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); + return -EINVAL; + fail_mem: + /* If any call succeeded, we still need to sync */ + if (!fail) + synchronize_sched(); + list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { + __free_filter(filter_item->filter); + list_del(&filter_item->list); + kfree(filter_item); + } + return -ENOMEM; } int apply_event_filter(struct ftrace_event_call *call, char *filter_string) { - int err; struct filter_parse_state *ps; + struct event_filter *filter; + struct event_filter *tmp; + int err = 0; mutex_lock(&event_mutex); - err = init_preds(call); - if (err) - goto out_unlock; - if (!strcmp(strstrip(filter_string), "0")) { - filter_disable_preds(call); - remove_filter_string(call->filter); + filter_disable(call); + filter = call->filter; + if (!filter) + goto out_unlock; + call->filter = NULL; + /* Make sure the filter is not being used */ + synchronize_sched(); + __free_filter(filter); goto out_unlock; } @@ -1306,22 +1833,41 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string) if (!ps) goto out_unlock; - filter_disable_preds(call); - replace_filter_string(call->filter, filter_string); + filter = __alloc_filter(); + if (!filter) { + kfree(ps); + goto out_unlock; + } + + replace_filter_string(filter, filter_string); parse_init(ps, filter_ops, filter_string); err = filter_parse(ps); if (err) { - append_filter_err(ps, call->filter); + append_filter_err(ps, filter); goto out; } - err = replace_preds(call, call->filter, ps, filter_string, false); - if (err) - append_filter_err(ps, call->filter); - else + err = replace_preds(call, filter, ps, filter_string, false); + if (err) { + filter_disable(call); + append_filter_err(ps, filter); + } else call->flags |= TRACE_EVENT_FL_FILTERED; out: + /* + * Always swap the call filter with the new filter + * even if there was an error. If there was an error + * in the filter, we disable the filter and show the error + * string + */ + tmp = call->filter; + call->filter = filter; + if (tmp) { + /* Make sure the call is done with the filter */ + synchronize_sched(); + __free_filter(tmp); + } filter_opstack_clear(ps); postfix_clear(ps); kfree(ps); @@ -1334,18 +1880,21 @@ out_unlock: int apply_subsystem_event_filter(struct event_subsystem *system, char *filter_string) { - int err; struct filter_parse_state *ps; + struct event_filter *filter; + int err = 0; mutex_lock(&event_mutex); - err = init_subsystem_preds(system); - if (err) - goto out_unlock; - if (!strcmp(strstrip(filter_string), "0")) { filter_free_subsystem_preds(system); remove_filter_string(system->filter); + filter = system->filter; + system->filter = NULL; + /* Ensure all filters are no longer used */ + synchronize_sched(); + filter_free_subsystem_filters(system); + __free_filter(filter); goto out_unlock; } @@ -1354,7 +1903,17 @@ int apply_subsystem_event_filter(struct event_subsystem *system, if (!ps) goto out_unlock; - replace_filter_string(system->filter, filter_string); + filter = __alloc_filter(); + if (!filter) + goto out; + + replace_filter_string(filter, filter_string); + /* + * No event actually uses the system filter + * we can free it without synchronize_sched(). + */ + __free_filter(system->filter); + system->filter = filter; parse_init(ps, filter_ops, filter_string); err = filter_parse(ps); @@ -1384,7 +1943,7 @@ void ftrace_profile_free_filter(struct perf_event *event) struct event_filter *filter = event->filter; event->filter = NULL; - __free_preds(filter); + __free_filter(filter); } int ftrace_profile_set_filter(struct perf_event *event, int event_id, @@ -1410,8 +1969,8 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id, if (event->filter) goto out_unlock; - filter = __alloc_preds(); - if (IS_ERR(filter)) { + filter = __alloc_filter(); + if (!filter) { err = PTR_ERR(filter); goto out_unlock; } @@ -1419,7 +1978,7 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id, err = -ENOMEM; ps = kzalloc(sizeof(*ps), GFP_KERNEL); if (!ps) - goto free_preds; + goto free_filter; parse_init(ps, filter_ops, filter_str); err = filter_parse(ps); @@ -1435,9 +1994,9 @@ free_ps: postfix_clear(ps); kfree(ps); -free_preds: +free_filter: if (err) - __free_preds(filter); + __free_filter(filter); out_unlock: mutex_unlock(&event_mutex); diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index 4ba44deaac2..bbeec31e0ae 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -83,13 +83,19 @@ static void __always_unused ____ftrace_check_##name(void) \ #undef __array #define __array(type, item, len) \ - BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ - ret = trace_define_field(event_call, #type "[" #len "]", #item, \ + do { \ + BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \ + mutex_lock(&event_storage_mutex); \ + snprintf(event_storage, sizeof(event_storage), \ + "%s[%d]", #type, len); \ + ret = trace_define_field(event_call, event_storage, #item, \ offsetof(typeof(field), item), \ sizeof(field.item), \ is_signed_type(type), FILTER_OTHER); \ - if (ret) \ - return ret; + mutex_unlock(&event_storage_mutex); \ + if (ret) \ + return ret; \ + } while (0); #undef __array_desc #define __array_desc(type, container, item, len) \ @@ -155,13 +161,13 @@ struct ftrace_event_class event_class_ftrace_##call = { \ .fields = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\ }; \ \ -struct ftrace_event_call __used \ -__attribute__((__aligned__(4))) \ -__attribute__((section("_ftrace_events"))) event_##call = { \ +struct ftrace_event_call __used event_##call = { \ .name = #call, \ .event.type = etype, \ .class = &event_class_ftrace_##call, \ .print_fmt = print, \ }; \ +struct ftrace_event_call __used \ +__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call; #include "trace_entries.h" diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 16aee4d44e8..8d0e1cc4e97 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -149,11 +149,13 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip) static struct ftrace_ops trace_ops __read_mostly = { .func = function_trace_call, + .flags = FTRACE_OPS_FL_GLOBAL, }; static struct ftrace_ops trace_stack_ops __read_mostly = { .func = function_stack_trace_call, + .flags = FTRACE_OPS_FL_GLOBAL, }; /* Our two options */ diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 76b05980225..962cdb24ed8 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -905,7 +905,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, * * returns 1 if * - we are inside irq code - * - we just extered irq code + * - we just entered irq code * * retunns 0 if * - funcgraph-interrupts option is set diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 5cf8c602b88..c77424be284 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -80,7 +80,7 @@ static struct tracer_flags tracer_flags = { * skip the latency if the sequence has changed - some other section * did a maximum and could disturb our measurement with serial console * printouts, etc. Truly coinciding maximum latencies should be rare - * and what happens together happens separately as well, so this doesnt + * and what happens together happens separately as well, so this doesn't * decrease the validity of the maximum found: */ static __cacheline_aligned_in_smp unsigned long max_sequence; @@ -153,6 +153,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip) static struct ftrace_ops trace_ops __read_mostly = { .func = irqsoff_tracer_call, + .flags = FTRACE_OPS_FL_GLOBAL, }; #endif /* CONFIG_FUNCTION_TRACER */ @@ -453,14 +454,6 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1) * Stubs: */ -void early_boot_irqs_off(void) -{ -} - -void early_boot_irqs_on(void) -{ -} - void trace_softirqs_on(unsigned long ip) { } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 2dec9bcde8b..f925c45f0af 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -53,7 +53,6 @@ const char *reserved_field_names[] = { "common_preempt_count", "common_pid", "common_tgid", - "common_lock_depth", FIELD_STRING_IP, FIELD_STRING_RETIP, FIELD_STRING_FUNC, @@ -353,6 +352,43 @@ static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data) kfree(data); } +/* Bitfield fetch function */ +struct bitfield_fetch_param { + struct fetch_param orig; + unsigned char hi_shift; + unsigned char low_shift; +}; + +#define DEFINE_FETCH_bitfield(type) \ +static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\ + void *data, void *dest) \ +{ \ + struct bitfield_fetch_param *bprm = data; \ + type buf = 0; \ + call_fetch(&bprm->orig, regs, &buf); \ + if (buf) { \ + buf <<= bprm->hi_shift; \ + buf >>= bprm->low_shift; \ + } \ + *(type *)dest = buf; \ +} +DEFINE_BASIC_FETCH_FUNCS(bitfield) +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +static __kprobes void +free_bitfield_fetch_param(struct bitfield_fetch_param *data) +{ + /* + * Don't check the bitfield itself, because this must be the + * last fetch function. + */ + if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) + free_deref_fetch_param(data->orig.data); + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) + free_symbol_cache(data->orig.data); + kfree(data); +} /* Default (unsigned long) fetch type */ #define __DEFAULT_FETCH_TYPE(t) u##t #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) @@ -367,6 +403,7 @@ enum { FETCH_MTD_memory, FETCH_MTD_symbol, FETCH_MTD_deref, + FETCH_MTD_bitfield, FETCH_MTD_END, }; @@ -387,6 +424,7 @@ ASSIGN_FETCH_FUNC(retval, ftype), \ ASSIGN_FETCH_FUNC(memory, ftype), \ ASSIGN_FETCH_FUNC(symbol, ftype), \ ASSIGN_FETCH_FUNC(deref, ftype), \ +ASSIGN_FETCH_FUNC(bitfield, ftype), \ } \ } @@ -430,9 +468,33 @@ static const struct fetch_type *find_fetch_type(const char *type) if (!type) type = DEFAULT_FETCH_TYPE_STR; + /* Special case: bitfield */ + if (*type == 'b') { + unsigned long bs; + type = strchr(type, '/'); + if (!type) + goto fail; + type++; + if (strict_strtoul(type, 0, &bs)) + goto fail; + switch (bs) { + case 8: + return find_fetch_type("u8"); + case 16: + return find_fetch_type("u16"); + case 32: + return find_fetch_type("u32"); + case 64: + return find_fetch_type("u64"); + default: + goto fail; + } + } + for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) if (strcmp(type, fetch_type_table[i].name) == 0) return &fetch_type_table[i]; +fail: return NULL; } @@ -586,7 +648,9 @@ error: static void free_probe_arg(struct probe_arg *arg) { - if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) + free_bitfield_fetch_param(arg->fetch.data); + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) free_deref_fetch_param(arg->fetch.data); else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) free_symbol_cache(arg->fetch.data); @@ -767,16 +831,15 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t, } break; case '+': /* deref memory */ + arg++; /* Skip '+', because strict_strtol() rejects it. */ case '-': tmp = strchr(arg, '('); if (!tmp) break; *tmp = '\0'; - ret = strict_strtol(arg + 1, 0, &offset); + ret = strict_strtol(arg, 0, &offset); if (ret) break; - if (arg[0] == '-') - offset = -offset; arg = tmp + 1; tmp = strrchr(arg, ')'); if (tmp) { @@ -807,6 +870,41 @@ static int __parse_probe_arg(char *arg, const struct fetch_type *t, return ret; } +#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) + +/* Bitfield type needs to be parsed into a fetch function */ +static int __parse_bitfield_probe_arg(const char *bf, + const struct fetch_type *t, + struct fetch_param *f) +{ + struct bitfield_fetch_param *bprm; + unsigned long bw, bo; + char *tail; + + if (*bf != 'b') + return 0; + + bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); + if (!bprm) + return -ENOMEM; + bprm->orig = *f; + f->fn = t->fetch[FETCH_MTD_bitfield]; + f->data = (void *)bprm; + + bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ + if (bw == 0 || *tail != '@') + return -EINVAL; + + bf = tail + 1; + bo = simple_strtoul(bf, &tail, 0); + if (tail == bf || *tail != '/') + return -EINVAL; + + bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo); + bprm->low_shift = bprm->hi_shift + bo; + return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; +} + /* String length checking wrapper */ static int parse_probe_arg(char *arg, struct trace_probe *tp, struct probe_arg *parg, int is_return) @@ -836,6 +934,8 @@ static int parse_probe_arg(char *arg, struct trace_probe *tp, parg->offset = tp->size; tp->size += parg->type->size; ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return); + if (ret >= 0 && t != NULL) + ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); if (ret >= 0) { parg->fetch_size.fn = get_fetch_size_function(parg->type, parg->fetch.fn); @@ -1130,7 +1230,7 @@ static int command_trace_probe(const char *buf) return ret; } -#define WRITE_BUFSIZE 128 +#define WRITE_BUFSIZE 4096 static ssize_t probes_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) @@ -1738,7 +1838,7 @@ static void unregister_probe_event(struct trace_probe *tp) kfree(tp->call.print_fmt); } -/* Make a debugfs interface for controling probe points */ +/* Make a debugfs interface for controlling probe points */ static __init int init_kprobe_trace(void) { struct dentry *d_tracer; diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 02272baa220..cf535ccedc8 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -529,24 +529,34 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) * @entry: The trace entry field from the ring buffer * * Prints the generic fields of irqs off, in hard or softirq, preempt - * count and lock depth. + * count. */ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) { - int hardirq, softirq; + char hardsoft_irq; + char need_resched; + char irqs_off; + int hardirq; + int softirq; int ret; hardirq = entry->flags & TRACE_FLAG_HARDIRQ; softirq = entry->flags & TRACE_FLAG_SOFTIRQ; + irqs_off = + (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : + (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : + '.'; + need_resched = + (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.'; + hardsoft_irq = + (hardirq && softirq) ? 'H' : + hardirq ? 'h' : + softirq ? 's' : + '.'; + if (!trace_seq_printf(s, "%c%c%c", - (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : - (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? - 'X' : '.', - (entry->flags & TRACE_FLAG_NEED_RESCHED) ? - 'N' : '.', - (hardirq && softirq) ? 'H' : - hardirq ? 'h' : softirq ? 's' : '.')) + irqs_off, need_resched, hardsoft_irq)) return 0; if (entry->preempt_count) @@ -554,13 +564,7 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) else ret = trace_seq_putc(s, '.'); - if (!ret) - return 0; - - if (entry->lock_depth < 0) - return trace_seq_putc(s, '.'); - - return trace_seq_printf(s, "%d", entry->lock_depth); + return ret; } static int @@ -826,6 +830,9 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_event); enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags, struct trace_event *event) { + if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type)) + return TRACE_TYPE_PARTIAL_LINE; + return TRACE_TYPE_HANDLED; } diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index 2547d8813cf..dff763b7baf 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -32,7 +32,7 @@ static DEFINE_MUTEX(btrace_mutex); struct trace_bprintk_fmt { struct list_head list; - char fmt[0]; + const char *fmt; }; static inline struct trace_bprintk_fmt *lookup_format(const char *fmt) @@ -49,6 +49,7 @@ static void hold_module_trace_bprintk_format(const char **start, const char **end) { const char **iter; + char *fmt; mutex_lock(&btrace_mutex); for (iter = start; iter < end; iter++) { @@ -58,14 +59,18 @@ void hold_module_trace_bprintk_format(const char **start, const char **end) continue; } - tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt) - + strlen(*iter) + 1, GFP_KERNEL); - if (tb_fmt) { + tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL); + if (tb_fmt) + fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL); + if (tb_fmt && fmt) { list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list); - strcpy(tb_fmt->fmt, *iter); + strcpy(fmt, *iter); + tb_fmt->fmt = fmt; *iter = tb_fmt->fmt; - } else + } else { + kfree(tb_fmt); *iter = NULL; + } } mutex_unlock(&btrace_mutex); } @@ -84,6 +89,76 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self, return 0; } +/* + * The debugfs/tracing/printk_formats file maps the addresses with + * the ASCII formats that are used in the bprintk events in the + * buffer. For userspace tools to be able to decode the events from + * the buffer, they need to be able to map the address with the format. + * + * The addresses of the bprintk formats are in their own section + * __trace_printk_fmt. But for modules we copy them into a link list. + * The code to print the formats and their addresses passes around the + * address of the fmt string. If the fmt address passed into the seq + * functions is within the kernel core __trace_printk_fmt section, then + * it simply uses the next pointer in the list. + * + * When the fmt pointer is outside the kernel core __trace_printk_fmt + * section, then we need to read the link list pointers. The trick is + * we pass the address of the string to the seq function just like + * we do for the kernel core formats. To get back the structure that + * holds the format, we simply use containerof() and then go to the + * next format in the list. + */ +static const char ** +find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos) +{ + struct trace_bprintk_fmt *mod_fmt; + + if (list_empty(&trace_bprintk_fmt_list)) + return NULL; + + /* + * v will point to the address of the fmt record from t_next + * v will be NULL from t_start. + * If this is the first pointer or called from start + * then we need to walk the list. + */ + if (!v || start_index == *pos) { + struct trace_bprintk_fmt *p; + + /* search the module list */ + list_for_each_entry(p, &trace_bprintk_fmt_list, list) { + if (start_index == *pos) + return &p->fmt; + start_index++; + } + /* pos > index */ + return NULL; + } + + /* + * v points to the address of the fmt field in the mod list + * structure that holds the module print format. + */ + mod_fmt = container_of(v, typeof(*mod_fmt), fmt); + if (mod_fmt->list.next == &trace_bprintk_fmt_list) + return NULL; + + mod_fmt = container_of(mod_fmt->list.next, typeof(*mod_fmt), list); + + return &mod_fmt->fmt; +} + +static void format_mod_start(void) +{ + mutex_lock(&btrace_mutex); +} + +static void format_mod_stop(void) +{ + mutex_unlock(&btrace_mutex); +} + #else /* !CONFIG_MODULES */ __init static int module_trace_bprintk_format_notify(struct notifier_block *self, @@ -91,6 +166,13 @@ module_trace_bprintk_format_notify(struct notifier_block *self, { return 0; } +static inline const char ** +find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos) +{ + return NULL; +} +static inline void format_mod_start(void) { } +static inline void format_mod_stop(void) { } #endif /* CONFIG_MODULES */ @@ -153,20 +235,33 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) } EXPORT_SYMBOL_GPL(__ftrace_vprintk); +static const char **find_next(void *v, loff_t *pos) +{ + const char **fmt = v; + int start_index; + + if (!fmt) + fmt = __start___trace_bprintk_fmt + *pos; + + start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt; + + if (*pos < start_index) + return fmt; + + return find_next_mod_format(start_index, v, fmt, pos); +} + static void * t_start(struct seq_file *m, loff_t *pos) { - const char **fmt = __start___trace_bprintk_fmt + *pos; - - if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt) - return NULL; - return fmt; + format_mod_start(); + return find_next(NULL, pos); } static void *t_next(struct seq_file *m, void * v, loff_t *pos) { (*pos)++; - return t_start(m, pos); + return find_next(v, pos); } static int t_show(struct seq_file *m, void *v) @@ -205,6 +300,7 @@ static int t_show(struct seq_file *m, void *v) static void t_stop(struct seq_file *m, void *p) { + format_mod_stop(); } static const struct seq_operations show_format_seq_ops = { diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 8f758d070c4..7e62c0a1845 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -247,51 +247,3 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr) ctx_trace = tr; } -static void stop_sched_trace(struct trace_array *tr) -{ - tracing_stop_sched_switch_record(); -} - -static int sched_switch_trace_init(struct trace_array *tr) -{ - ctx_trace = tr; - tracing_reset_online_cpus(tr); - tracing_start_sched_switch_record(); - return 0; -} - -static void sched_switch_trace_reset(struct trace_array *tr) -{ - if (sched_ref) - stop_sched_trace(tr); -} - -static void sched_switch_trace_start(struct trace_array *tr) -{ - sched_stopped = 0; -} - -static void sched_switch_trace_stop(struct trace_array *tr) -{ - sched_stopped = 1; -} - -static struct tracer sched_switch_trace __read_mostly = -{ - .name = "sched_switch", - .init = sched_switch_trace_init, - .reset = sched_switch_trace_reset, - .start = sched_switch_trace_start, - .stop = sched_switch_trace_stop, - .wait_pipe = poll_wait_pipe, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_sched_switch, -#endif -}; - -__init static int init_sched_switch_trace(void) -{ - return register_tracer(&sched_switch_trace); -} -device_initcall(init_sched_switch_trace); - diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 7319559ed59..f029dd4fd2c 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -129,6 +129,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip) static struct ftrace_ops trace_ops __read_mostly = { .func = wakeup_tracer_call, + .flags = FTRACE_OPS_FL_GLOBAL, }; #endif /* CONFIG_FUNCTION_TRACER */ diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 155a415b320..288541f977f 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -101,6 +101,206 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret) #ifdef CONFIG_DYNAMIC_FTRACE +static int trace_selftest_test_probe1_cnt; +static void trace_selftest_test_probe1_func(unsigned long ip, + unsigned long pip) +{ + trace_selftest_test_probe1_cnt++; +} + +static int trace_selftest_test_probe2_cnt; +static void trace_selftest_test_probe2_func(unsigned long ip, + unsigned long pip) +{ + trace_selftest_test_probe2_cnt++; +} + +static int trace_selftest_test_probe3_cnt; +static void trace_selftest_test_probe3_func(unsigned long ip, + unsigned long pip) +{ + trace_selftest_test_probe3_cnt++; +} + +static int trace_selftest_test_global_cnt; +static void trace_selftest_test_global_func(unsigned long ip, + unsigned long pip) +{ + trace_selftest_test_global_cnt++; +} + +static int trace_selftest_test_dyn_cnt; +static void trace_selftest_test_dyn_func(unsigned long ip, + unsigned long pip) +{ + trace_selftest_test_dyn_cnt++; +} + +static struct ftrace_ops test_probe1 = { + .func = trace_selftest_test_probe1_func, +}; + +static struct ftrace_ops test_probe2 = { + .func = trace_selftest_test_probe2_func, +}; + +static struct ftrace_ops test_probe3 = { + .func = trace_selftest_test_probe3_func, +}; + +static struct ftrace_ops test_global = { + .func = trace_selftest_test_global_func, + .flags = FTRACE_OPS_FL_GLOBAL, +}; + +static void print_counts(void) +{ + printk("(%d %d %d %d %d) ", + trace_selftest_test_probe1_cnt, + trace_selftest_test_probe2_cnt, + trace_selftest_test_probe3_cnt, + trace_selftest_test_global_cnt, + trace_selftest_test_dyn_cnt); +} + +static void reset_counts(void) +{ + trace_selftest_test_probe1_cnt = 0; + trace_selftest_test_probe2_cnt = 0; + trace_selftest_test_probe3_cnt = 0; + trace_selftest_test_global_cnt = 0; + trace_selftest_test_dyn_cnt = 0; +} + +static int trace_selftest_ops(int cnt) +{ + int save_ftrace_enabled = ftrace_enabled; + struct ftrace_ops *dyn_ops; + char *func1_name; + char *func2_name; + int len1; + int len2; + int ret = -1; + + printk(KERN_CONT "PASSED\n"); + pr_info("Testing dynamic ftrace ops #%d: ", cnt); + + ftrace_enabled = 1; + reset_counts(); + + /* Handle PPC64 '.' name */ + func1_name = "*" __stringify(DYN_FTRACE_TEST_NAME); + func2_name = "*" __stringify(DYN_FTRACE_TEST_NAME2); + len1 = strlen(func1_name); + len2 = strlen(func2_name); + + /* + * Probe 1 will trace function 1. + * Probe 2 will trace function 2. + * Probe 3 will trace functions 1 and 2. + */ + ftrace_set_filter(&test_probe1, func1_name, len1, 1); + ftrace_set_filter(&test_probe2, func2_name, len2, 1); + ftrace_set_filter(&test_probe3, func1_name, len1, 1); + ftrace_set_filter(&test_probe3, func2_name, len2, 0); + + register_ftrace_function(&test_probe1); + register_ftrace_function(&test_probe2); + register_ftrace_function(&test_probe3); + register_ftrace_function(&test_global); + + DYN_FTRACE_TEST_NAME(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 1) + goto out; + if (trace_selftest_test_probe2_cnt != 0) + goto out; + if (trace_selftest_test_probe3_cnt != 1) + goto out; + if (trace_selftest_test_global_cnt == 0) + goto out; + + DYN_FTRACE_TEST_NAME2(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 1) + goto out; + if (trace_selftest_test_probe2_cnt != 1) + goto out; + if (trace_selftest_test_probe3_cnt != 2) + goto out; + + /* Add a dynamic probe */ + dyn_ops = kzalloc(sizeof(*dyn_ops), GFP_KERNEL); + if (!dyn_ops) { + printk("MEMORY ERROR "); + goto out; + } + + dyn_ops->func = trace_selftest_test_dyn_func; + + register_ftrace_function(dyn_ops); + + trace_selftest_test_global_cnt = 0; + + DYN_FTRACE_TEST_NAME(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 2) + goto out_free; + if (trace_selftest_test_probe2_cnt != 1) + goto out_free; + if (trace_selftest_test_probe3_cnt != 3) + goto out_free; + if (trace_selftest_test_global_cnt == 0) + goto out; + if (trace_selftest_test_dyn_cnt == 0) + goto out_free; + + DYN_FTRACE_TEST_NAME2(); + + print_counts(); + + if (trace_selftest_test_probe1_cnt != 2) + goto out_free; + if (trace_selftest_test_probe2_cnt != 2) + goto out_free; + if (trace_selftest_test_probe3_cnt != 4) + goto out_free; + + ret = 0; + out_free: + unregister_ftrace_function(dyn_ops); + kfree(dyn_ops); + + out: + /* Purposely unregister in the same order */ + unregister_ftrace_function(&test_probe1); + unregister_ftrace_function(&test_probe2); + unregister_ftrace_function(&test_probe3); + unregister_ftrace_function(&test_global); + + /* Make sure everything is off */ + reset_counts(); + DYN_FTRACE_TEST_NAME(); + DYN_FTRACE_TEST_NAME(); + + if (trace_selftest_test_probe1_cnt || + trace_selftest_test_probe2_cnt || + trace_selftest_test_probe3_cnt || + trace_selftest_test_global_cnt || + trace_selftest_test_dyn_cnt) + ret = -1; + + ftrace_enabled = save_ftrace_enabled; + + return ret; +} + /* Test dynamic code modification and ftrace filters */ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, struct trace_array *tr, @@ -131,7 +331,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); /* filter only on our function */ - ftrace_set_filter(func_name, strlen(func_name), 1); + ftrace_set_global_filter(func_name, strlen(func_name), 1); /* enable tracing */ ret = tracer_init(trace, tr); @@ -166,22 +366,30 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace, /* check the trace buffer */ ret = trace_test_buffer(tr, &count); - trace->reset(tr); tracing_start(); /* we should only have one item */ if (!ret && count != 1) { + trace->reset(tr); printk(KERN_CONT ".. filter failed count=%ld ..", count); ret = -1; goto out; } + /* Test the ops with global tracing running */ + ret = trace_selftest_ops(1); + trace->reset(tr); + out: ftrace_enabled = save_ftrace_enabled; tracer_enabled = save_tracer_enabled; /* Enable tracing on all functions again */ - ftrace_set_filter(NULL, 0, 1); + ftrace_set_global_filter(NULL, 0, 1); + + /* Test the ops with global tracing off */ + if (!ret) + ret = trace_selftest_ops(2); return ret; } @@ -558,7 +766,7 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr) static int trace_wakeup_test_thread(void *data) { /* Make this a RT thread, doesn't need to be too high */ - struct sched_param param = { .sched_priority = 5 }; + static const struct sched_param param = { .sched_priority = 5 }; struct completion *x = data; sched_setscheduler(current, SCHED_FIFO, ¶m); diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c index 54dd77cce5b..b4c475a0a48 100644 --- a/kernel/trace/trace_selftest_dynamic.c +++ b/kernel/trace/trace_selftest_dynamic.c @@ -5,3 +5,9 @@ int DYN_FTRACE_TEST_NAME(void) /* used to call mcount */ return 0; } + +int DYN_FTRACE_TEST_NAME2(void) +{ + /* used to call mcount */ + return 0; +} diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 4c5dead0c23..b0b53b8e4c2 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -133,6 +133,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip) static struct ftrace_ops trace_ops __read_mostly = { .func = stack_trace_call, + .flags = FTRACE_OPS_FL_GLOBAL, }; static ssize_t diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index bac752f0cfb..ee7b5a0bb9f 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -23,9 +23,6 @@ static int syscall_exit_register(struct ftrace_event_call *event, static int syscall_enter_define_fields(struct ftrace_event_call *call); static int syscall_exit_define_fields(struct ftrace_event_call *call); -/* All syscall exit events have the same fields */ -static LIST_HEAD(syscall_exit_fields); - static struct list_head * syscall_get_enter_fields(struct ftrace_event_call *call) { @@ -34,61 +31,66 @@ syscall_get_enter_fields(struct ftrace_event_call *call) return &entry->enter_fields; } -static struct list_head * -syscall_get_exit_fields(struct ftrace_event_call *call) -{ - return &syscall_exit_fields; -} - struct trace_event_functions enter_syscall_print_funcs = { - .trace = print_syscall_enter, + .trace = print_syscall_enter, }; struct trace_event_functions exit_syscall_print_funcs = { - .trace = print_syscall_exit, + .trace = print_syscall_exit, }; struct ftrace_event_class event_class_syscall_enter = { - .system = "syscalls", - .reg = syscall_enter_register, - .define_fields = syscall_enter_define_fields, - .get_fields = syscall_get_enter_fields, - .raw_init = init_syscall_trace, + .system = "syscalls", + .reg = syscall_enter_register, + .define_fields = syscall_enter_define_fields, + .get_fields = syscall_get_enter_fields, + .raw_init = init_syscall_trace, }; struct ftrace_event_class event_class_syscall_exit = { - .system = "syscalls", - .reg = syscall_exit_register, - .define_fields = syscall_exit_define_fields, - .get_fields = syscall_get_exit_fields, - .raw_init = init_syscall_trace, + .system = "syscalls", + .reg = syscall_exit_register, + .define_fields = syscall_exit_define_fields, + .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields), + .raw_init = init_syscall_trace, }; -extern unsigned long __start_syscalls_metadata[]; -extern unsigned long __stop_syscalls_metadata[]; +extern struct syscall_metadata *__start_syscalls_metadata[]; +extern struct syscall_metadata *__stop_syscalls_metadata[]; static struct syscall_metadata **syscalls_metadata; -static struct syscall_metadata *find_syscall_meta(unsigned long syscall) +#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME +static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) +{ + /* + * Only compare after the "sys" prefix. Archs that use + * syscall wrappers may have syscalls symbols aliases prefixed + * with "SyS" instead of "sys", leading to an unwanted + * mismatch. + */ + return !strcmp(sym + 3, name + 3); +} +#endif + +static __init struct syscall_metadata * +find_syscall_meta(unsigned long syscall) { - struct syscall_metadata *start; - struct syscall_metadata *stop; + struct syscall_metadata **start; + struct syscall_metadata **stop; char str[KSYM_SYMBOL_LEN]; - start = (struct syscall_metadata *)__start_syscalls_metadata; - stop = (struct syscall_metadata *)__stop_syscalls_metadata; + start = __start_syscalls_metadata; + stop = __stop_syscalls_metadata; kallsyms_lookup(syscall, NULL, NULL, NULL, str); + if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) + return NULL; + for ( ; start < stop; start++) { - /* - * Only compare after the "sys" prefix. Archs that use - * syscall wrappers may have syscalls symbols aliases prefixed - * with "SyS" instead of "sys", leading to an unwanted - * mismatch. - */ - if (start->name && !strcmp(start->name + 3, str + 3)) - return start; + if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) + return *start; } return NULL; } @@ -367,7 +369,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_enter) @@ -385,7 +387,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_enter--; @@ -401,7 +403,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_exit) @@ -419,7 +421,7 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_exit--; @@ -432,6 +434,14 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call) int init_syscall_trace(struct ftrace_event_call *call) { int id; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (num < 0 || num >= NR_syscalls) { + pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", + ((struct syscall_metadata *)call->data)->name); + return -ENOSYS; + } if (set_syscall_print_fmt(call) < 0) return -ENOMEM; @@ -446,7 +456,7 @@ int init_syscall_trace(struct ftrace_event_call *call) return id; } -unsigned long __init arch_syscall_addr(int nr) +unsigned long __init __weak arch_syscall_addr(int nr) { return (unsigned long)sys_call_table[nr]; } diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index e95ee7f31d4..b219f1449c5 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -27,8 +27,8 @@ #include <linux/sched.h> #include <linux/jump_label.h> -extern struct tracepoint __start___tracepoints[]; -extern struct tracepoint __stop___tracepoints[]; +extern struct tracepoint * const __start___tracepoints_ptrs[]; +extern struct tracepoint * const __stop___tracepoints_ptrs[]; /* Set to 1 to enable tracepoint debug output */ static const int tracepoint_debug; @@ -251,9 +251,9 @@ static void set_tracepoint(struct tracepoint_entry **entry, { WARN_ON(strcmp((*entry)->name, elem->name) != 0); - if (elem->regfunc && !elem->state && active) + if (elem->regfunc && !jump_label_enabled(&elem->key) && active) elem->regfunc(); - else if (elem->unregfunc && elem->state && !active) + else if (elem->unregfunc && jump_label_enabled(&elem->key) && !active) elem->unregfunc(); /* @@ -264,13 +264,10 @@ static void set_tracepoint(struct tracepoint_entry **entry, * is used. */ rcu_assign_pointer(elem->funcs, (*entry)->funcs); - if (!elem->state && active) { - jump_label_enable(&elem->state); - elem->state = active; - } else if (elem->state && !active) { - jump_label_disable(&elem->state); - elem->state = active; - } + if (active && !jump_label_enabled(&elem->key)) + jump_label_inc(&elem->key); + else if (!active && jump_label_enabled(&elem->key)) + jump_label_dec(&elem->key); } /* @@ -281,13 +278,11 @@ static void set_tracepoint(struct tracepoint_entry **entry, */ static void disable_tracepoint(struct tracepoint *elem) { - if (elem->unregfunc && elem->state) + if (elem->unregfunc && jump_label_enabled(&elem->key)) elem->unregfunc(); - if (elem->state) { - jump_label_disable(&elem->state); - elem->state = 0; - } + if (jump_label_enabled(&elem->key)) + jump_label_dec(&elem->key); rcu_assign_pointer(elem->funcs, NULL); } @@ -298,10 +293,10 @@ static void disable_tracepoint(struct tracepoint *elem) * * Updates the probe callback corresponding to a range of tracepoints. */ -void -tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end) +void tracepoint_update_probe_range(struct tracepoint * const *begin, + struct tracepoint * const *end) { - struct tracepoint *iter; + struct tracepoint * const *iter; struct tracepoint_entry *mark_entry; if (!begin) @@ -309,12 +304,12 @@ tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end) mutex_lock(&tracepoints_mutex); for (iter = begin; iter < end; iter++) { - mark_entry = get_tracepoint(iter->name); + mark_entry = get_tracepoint((*iter)->name); if (mark_entry) { - set_tracepoint(&mark_entry, iter, + set_tracepoint(&mark_entry, *iter, !!mark_entry->refcount); } else { - disable_tracepoint(iter); + disable_tracepoint(*iter); } } mutex_unlock(&tracepoints_mutex); @@ -326,8 +321,8 @@ tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end) static void tracepoint_update_probes(void) { /* Core kernel tracepoints */ - tracepoint_update_probe_range(__start___tracepoints, - __stop___tracepoints); + tracepoint_update_probe_range(__start___tracepoints_ptrs, + __stop___tracepoints_ptrs); /* tracepoints in modules. */ module_update_tracepoints(); } @@ -514,8 +509,8 @@ EXPORT_SYMBOL_GPL(tracepoint_probe_update_all); * Will return the first tracepoint in the range if the input tracepoint is * NULL. */ -int tracepoint_get_iter_range(struct tracepoint **tracepoint, - struct tracepoint *begin, struct tracepoint *end) +int tracepoint_get_iter_range(struct tracepoint * const **tracepoint, + struct tracepoint * const *begin, struct tracepoint * const *end) { if (!*tracepoint && begin != end) { *tracepoint = begin; @@ -534,7 +529,8 @@ static void tracepoint_get_iter(struct tracepoint_iter *iter) /* Core kernel tracepoints */ if (!iter->module) { found = tracepoint_get_iter_range(&iter->tracepoint, - __start___tracepoints, __stop___tracepoints); + __start___tracepoints_ptrs, + __stop___tracepoints_ptrs); if (found) goto end; } @@ -585,8 +581,8 @@ int tracepoint_module_notify(struct notifier_block *self, switch (val) { case MODULE_STATE_COMING: case MODULE_STATE_GOING: - tracepoint_update_probe_range(mod->tracepoints, - mod->tracepoints + mod->num_tracepoints); + tracepoint_update_probe_range(mod->tracepoints_ptrs, + mod->tracepoints_ptrs + mod->num_tracepoints); break; } return 0; diff --git a/kernel/uid16.c b/kernel/uid16.c index 419209893d8..51c6e89e861 100644 --- a/kernel/uid16.c +++ b/kernel/uid16.c @@ -189,7 +189,7 @@ SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist) struct group_info *group_info; int retval; - if (!capable(CAP_SETGID)) + if (!nsown_capable(CAP_SETGID)) return -EPERM; if ((unsigned)gidsetsize > NGROUPS_MAX) return -EINVAL; diff --git a/kernel/user-return-notifier.c b/kernel/user-return-notifier.c index eb27fd3430a..92cb706c7fc 100644 --- a/kernel/user-return-notifier.c +++ b/kernel/user-return-notifier.c @@ -20,7 +20,7 @@ EXPORT_SYMBOL_GPL(user_return_notifier_register); /* * Removes a registered user return notifier. Must be called from atomic - * context, and from the same cpu registration occured in. + * context, and from the same cpu registration occurred in. */ void user_return_notifier_unregister(struct user_return_notifier *urn) { diff --git a/kernel/user.c b/kernel/user.c index 2c7d8d5914b..9e03e9c1df8 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -17,9 +17,13 @@ #include <linux/module.h> #include <linux/user_namespace.h> +/* + * userns count is 1 for root user, 1 for init_uts_ns, + * and 1 for... ? + */ struct user_namespace init_user_ns = { .kref = { - .refcount = ATOMIC_INIT(2), + .refcount = ATOMIC_INIT(3), }, .creator = &root_user, }; @@ -47,7 +51,7 @@ static struct kmem_cache *uid_cachep; */ static DEFINE_SPINLOCK(uidhash_lock); -/* root_user.__count is 2, 1 for init task cred, 1 for init_user_ns->creator */ +/* root_user.__count is 2, 1 for init task cred, 1 for init_user_ns->user_ns */ struct user_struct root_user = { .__count = ATOMIC_INIT(2), .processes = ATOMIC_INIT(1), @@ -158,6 +162,7 @@ struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid) spin_lock_irq(&uidhash_lock); up = uid_hash_find(uid, hashent); if (up) { + put_user_ns(ns); key_put(new->uid_keyring); key_put(new->session_keyring); kmem_cache_free(uid_cachep, new); diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index 25915832291..9da289c34f2 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -12,6 +12,8 @@ #include <linux/highuid.h> #include <linux/cred.h> +static struct kmem_cache *user_ns_cachep __read_mostly; + /* * Create a new user namespace, deriving the creator from the user in the * passed credentials, and replacing that user with the new root user for the @@ -26,7 +28,7 @@ int create_user_ns(struct cred *new) struct user_struct *root_user; int n; - ns = kmalloc(sizeof(struct user_namespace), GFP_KERNEL); + ns = kmem_cache_alloc(user_ns_cachep, GFP_KERNEL); if (!ns) return -ENOMEM; @@ -38,7 +40,7 @@ int create_user_ns(struct cred *new) /* Alloc new root user. */ root_user = alloc_uid(ns, 0); if (!root_user) { - kfree(ns); + kmem_cache_free(user_ns_cachep, ns); return -ENOMEM; } @@ -71,7 +73,7 @@ static void free_user_ns_work(struct work_struct *work) struct user_namespace *ns = container_of(work, struct user_namespace, destroyer); free_uid(ns->creator); - kfree(ns); + kmem_cache_free(user_ns_cachep, ns); } void free_user_ns(struct kref *kref) @@ -126,3 +128,10 @@ gid_t user_ns_map_gid(struct user_namespace *to, const struct cred *cred, gid_t /* No useful relationship so no mapping */ return overflowgid; } + +static __init int user_namespaces_init(void) +{ + user_ns_cachep = KMEM_CACHE(user_namespace, SLAB_PANIC); + return 0; +} +module_init(user_namespaces_init); diff --git a/kernel/utsname.c b/kernel/utsname.c index 8a82b4b8ea5..44646179eab 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -14,6 +14,7 @@ #include <linux/utsname.h> #include <linux/err.h> #include <linux/slab.h> +#include <linux/user_namespace.h> static struct uts_namespace *create_uts_ns(void) { @@ -30,7 +31,8 @@ static struct uts_namespace *create_uts_ns(void) * @old_ns: namespace to clone * Return NULL on error (failure to kmalloc), new ns otherwise */ -static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns) +static struct uts_namespace *clone_uts_ns(struct task_struct *tsk, + struct uts_namespace *old_ns) { struct uts_namespace *ns; @@ -40,6 +42,7 @@ static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns) down_read(&uts_sem); memcpy(&ns->name, &old_ns->name, sizeof(ns->name)); + ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns); up_read(&uts_sem); return ns; } @@ -50,8 +53,10 @@ static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns) * utsname of this process won't be seen by parent, and vice * versa. */ -struct uts_namespace *copy_utsname(unsigned long flags, struct uts_namespace *old_ns) +struct uts_namespace *copy_utsname(unsigned long flags, + struct task_struct *tsk) { + struct uts_namespace *old_ns = tsk->nsproxy->uts_ns; struct uts_namespace *new_ns; BUG_ON(!old_ns); @@ -60,7 +65,7 @@ struct uts_namespace *copy_utsname(unsigned long flags, struct uts_namespace *ol if (!(flags & CLONE_NEWUTS)) return old_ns; - new_ns = clone_uts_ns(old_ns); + new_ns = clone_uts_ns(tsk, old_ns); put_uts_ns(old_ns); return new_ns; @@ -71,5 +76,6 @@ void free_uts_ns(struct kref *kref) struct uts_namespace *ns; ns = container_of(kref, struct uts_namespace, kref); + put_user_ns(ns->user_ns); kfree(ns); } diff --git a/kernel/wait.c b/kernel/wait.c index b0310eb6cc1..f45ea8d2a1c 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -142,7 +142,7 @@ EXPORT_SYMBOL(finish_wait); * woken up through the queue. * * This prevents waiter starvation where an exclusive waiter - * aborts and is woken up concurrently and noone wakes up + * aborts and is woken up concurrently and no one wakes up * the next waiter. */ void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, diff --git a/kernel/watchdog.c b/kernel/watchdog.c index bafba687a6d..6e63097fa73 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -27,8 +27,8 @@ #include <asm/irq_regs.h> #include <linux/perf_event.h> -int watchdog_enabled; -int __read_mostly softlockup_thresh = 60; +int watchdog_enabled = 1; +int __read_mostly watchdog_thresh = 10; static DEFINE_PER_CPU(unsigned long, watchdog_touch_ts); static DEFINE_PER_CPU(struct task_struct *, softlockup_watchdog); @@ -43,20 +43,22 @@ static DEFINE_PER_CPU(unsigned long, hrtimer_interrupts_saved); static DEFINE_PER_CPU(struct perf_event *, watchdog_ev); #endif -static int __initdata no_watchdog; - - /* boot commands */ /* * Should we panic when a soft-lockup or hard-lockup occurs: */ #ifdef CONFIG_HARDLOCKUP_DETECTOR -static int hardlockup_panic; +static int hardlockup_panic = + CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE; static int __init hardlockup_panic_setup(char *str) { if (!strncmp(str, "panic", 5)) hardlockup_panic = 1; + else if (!strncmp(str, "nopanic", 7)) + hardlockup_panic = 0; + else if (!strncmp(str, "0", 1)) + watchdog_enabled = 0; return 1; } __setup("nmi_watchdog=", hardlockup_panic_setup); @@ -75,7 +77,7 @@ __setup("softlockup_panic=", softlockup_panic_setup); static int __init nowatchdog_setup(char *str) { - no_watchdog = 1; + watchdog_enabled = 0; return 1; } __setup("nowatchdog", nowatchdog_setup); @@ -83,12 +85,23 @@ __setup("nowatchdog", nowatchdog_setup); /* deprecated */ static int __init nosoftlockup_setup(char *str) { - no_watchdog = 1; + watchdog_enabled = 0; return 1; } __setup("nosoftlockup", nosoftlockup_setup); /* */ +/* + * Hard-lockup warnings should be triggered after just a few seconds. Soft- + * lockups can have false positives under extreme conditions. So we generally + * want a higher threshold for soft lockups than for hard lockups. So we couple + * the thresholds with a factor: we make the soft threshold twice the amount of + * time the hard threshold is. + */ +static int get_softlockup_thresh() +{ + return watchdog_thresh * 2; +} /* * Returns seconds, approximately. We don't need nanosecond @@ -103,12 +116,12 @@ static unsigned long get_timestamp(int this_cpu) static unsigned long get_sample_period(void) { /* - * convert softlockup_thresh from seconds to ns + * convert watchdog_thresh from seconds to ns * the divide by 5 is to give hrtimer 5 chances to * increment before the hardlockup detector generates * a warning */ - return softlockup_thresh / 5 * NSEC_PER_SEC; + return get_softlockup_thresh() * (NSEC_PER_SEC / 5); } /* Commands for resetting the watchdog */ @@ -116,12 +129,12 @@ static void __touch_watchdog(void) { int this_cpu = smp_processor_id(); - __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); + __this_cpu_write(watchdog_touch_ts, get_timestamp(this_cpu)); } void touch_softlockup_watchdog(void) { - __raw_get_cpu_var(watchdog_touch_ts) = 0; + __this_cpu_write(watchdog_touch_ts, 0); } EXPORT_SYMBOL(touch_softlockup_watchdog); @@ -165,12 +178,12 @@ void touch_softlockup_watchdog_sync(void) /* watchdog detector functions */ static int is_hardlockup(void) { - unsigned long hrint = __get_cpu_var(hrtimer_interrupts); + unsigned long hrint = __this_cpu_read(hrtimer_interrupts); - if (__get_cpu_var(hrtimer_interrupts_saved) == hrint) + if (__this_cpu_read(hrtimer_interrupts_saved) == hrint) return 1; - __get_cpu_var(hrtimer_interrupts_saved) = hrint; + __this_cpu_write(hrtimer_interrupts_saved, hrint); return 0; } #endif @@ -180,7 +193,7 @@ static int is_softlockup(unsigned long touch_ts) unsigned long now = get_timestamp(smp_processor_id()); /* Warn about unreasonable delays: */ - if (time_after(now, touch_ts + softlockup_thresh)) + if (time_after(now, touch_ts + get_softlockup_thresh())) return now - touch_ts; return 0; @@ -203,8 +216,8 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, /* Ensure the watchdog never gets throttled */ event->hw.interrupts = 0; - if (__get_cpu_var(watchdog_nmi_touch) == true) { - __get_cpu_var(watchdog_nmi_touch) = false; + if (__this_cpu_read(watchdog_nmi_touch) == true) { + __this_cpu_write(watchdog_nmi_touch, false); return; } @@ -218,7 +231,7 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, int this_cpu = smp_processor_id(); /* only print hardlockups once */ - if (__get_cpu_var(hard_watchdog_warn) == true) + if (__this_cpu_read(hard_watchdog_warn) == true) return; if (hardlockup_panic) @@ -226,16 +239,16 @@ static void watchdog_overflow_callback(struct perf_event *event, int nmi, else WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); - __get_cpu_var(hard_watchdog_warn) = true; + __this_cpu_write(hard_watchdog_warn, true); return; } - __get_cpu_var(hard_watchdog_warn) = false; + __this_cpu_write(hard_watchdog_warn, false); return; } static void watchdog_interrupt_count(void) { - __get_cpu_var(hrtimer_interrupts)++; + __this_cpu_inc(hrtimer_interrupts); } #else static inline void watchdog_interrupt_count(void) { return; } @@ -244,7 +257,7 @@ static inline void watchdog_interrupt_count(void) { return; } /* watchdog kicker functions */ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) { - unsigned long touch_ts = __get_cpu_var(watchdog_touch_ts); + unsigned long touch_ts = __this_cpu_read(watchdog_touch_ts); struct pt_regs *regs = get_irq_regs(); int duration; @@ -252,18 +265,18 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) watchdog_interrupt_count(); /* kick the softlockup detector */ - wake_up_process(__get_cpu_var(softlockup_watchdog)); + wake_up_process(__this_cpu_read(softlockup_watchdog)); /* .. and repeat */ hrtimer_forward_now(hrtimer, ns_to_ktime(get_sample_period())); if (touch_ts == 0) { - if (unlikely(__get_cpu_var(softlockup_touch_sync))) { + if (unlikely(__this_cpu_read(softlockup_touch_sync))) { /* * If the time stamp was touched atomically * make sure the scheduler tick is up to date. */ - __get_cpu_var(softlockup_touch_sync) = false; + __this_cpu_write(softlockup_touch_sync, false); sched_clock_tick(); } __touch_watchdog(); @@ -279,7 +292,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) duration = is_softlockup(touch_ts); if (unlikely(duration)) { /* only warn once */ - if (__get_cpu_var(soft_watchdog_warn) == true) + if (__this_cpu_read(soft_watchdog_warn) == true) return HRTIMER_RESTART; printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", @@ -294,9 +307,9 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) if (softlockup_panic) panic("softlockup: hung tasks"); - __get_cpu_var(soft_watchdog_warn) = true; + __this_cpu_write(soft_watchdog_warn, true); } else - __get_cpu_var(soft_watchdog_warn) = false; + __this_cpu_write(soft_watchdog_warn, false); return HRTIMER_RESTART; } @@ -307,7 +320,7 @@ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) */ static int watchdog(void *unused) { - struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + static struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; struct hrtimer *hrtimer = &__raw_get_cpu_var(watchdog_hrtimer); sched_setscheduler(current, SCHED_FIFO, ¶m); @@ -357,14 +370,21 @@ static int watchdog_nmi_enable(int cpu) /* Try to register using hardware perf events */ wd_attr = &wd_hw_attr; - wd_attr->sample_period = hw_nmi_get_sample_period(); + wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh); event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback); if (!IS_ERR(event)) { printk(KERN_INFO "NMI watchdog enabled, takes one hw-pmu counter.\n"); goto out_save; } - printk(KERN_ERR "NMI watchdog failed to create perf event on cpu%i: %p\n", cpu, event); + + /* vary the KERN level based on the returned errno */ + if (PTR_ERR(event) == -EOPNOTSUPP) + printk(KERN_INFO "NMI watchdog disabled (cpu%i): not supported (no LAPIC?)\n", cpu); + else if (PTR_ERR(event) == -ENOENT) + printk(KERN_WARNING "NMI watchdog disabled (cpu%i): hardware events not enabled\n", cpu); + else + printk(KERN_ERR "NMI watchdog disabled (cpu%i): unable to create perf event: %ld\n", cpu, PTR_ERR(event)); return PTR_ERR(event); /* success path */ @@ -409,19 +429,25 @@ static int watchdog_prepare_cpu(int cpu) static int watchdog_enable(int cpu) { struct task_struct *p = per_cpu(softlockup_watchdog, cpu); - int err; + int err = 0; /* enable the perf event */ err = watchdog_nmi_enable(cpu); - if (err) - return err; + + /* Regardless of err above, fall through and start softlockup */ /* create the watchdog thread */ if (!p) { p = kthread_create(watchdog, (void *)(unsigned long)cpu, "watchdog/%d", cpu); if (IS_ERR(p)) { printk(KERN_ERR "softlockup watchdog for %i failed\n", cpu); - return PTR_ERR(p); + if (!err) { + /* if hardlockup hasn't already set this */ + err = PTR_ERR(p); + /* and disable the perf event */ + watchdog_nmi_disable(cpu); + } + goto out; } kthread_bind(p, cpu); per_cpu(watchdog_touch_ts, cpu) = 0; @@ -429,10 +455,8 @@ static int watchdog_enable(int cpu) wake_up_process(p); } - /* if any cpu succeeds, watchdog is considered enabled for the system */ - watchdog_enabled = 1; - - return 0; +out: + return err; } static void watchdog_disable(int cpu) @@ -459,12 +483,16 @@ static void watchdog_disable(int cpu) static void watchdog_enable_all_cpus(void) { int cpu; - int result = 0; + + watchdog_enabled = 0; for_each_online_cpu(cpu) - result += watchdog_enable(cpu); + if (!watchdog_enable(cpu)) + /* if any cpu succeeds, watchdog is considered + enabled for the system */ + watchdog_enabled = 1; - if (result) + if (!watchdog_enabled) printk(KERN_ERR "watchdog: failed to be enabled on some cpus\n"); } @@ -473,9 +501,6 @@ static void watchdog_disable_all_cpus(void) { int cpu; - if (no_watchdog) - return; - for_each_online_cpu(cpu) watchdog_disable(cpu); @@ -487,26 +512,25 @@ static void watchdog_disable_all_cpus(void) /* sysctl functions */ #ifdef CONFIG_SYSCTL /* - * proc handler for /proc/sys/kernel/nmi_watchdog + * proc handler for /proc/sys/kernel/nmi_watchdog,watchdog_thresh */ -int proc_dowatchdog_enabled(struct ctl_table *table, int write, - void __user *buffer, size_t *length, loff_t *ppos) +int proc_dowatchdog(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) { - proc_dointvec(table, write, buffer, length, ppos); + int ret; - if (watchdog_enabled) + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + if (ret || !write) + goto out; + + if (watchdog_enabled && watchdog_thresh) watchdog_enable_all_cpus(); else watchdog_disable_all_cpus(); - return 0; -} -int proc_dowatchdog_thresh(struct ctl_table *table, int write, - void __user *buffer, - size_t *lenp, loff_t *ppos) -{ - return proc_dointvec_minmax(table, write, buffer, lenp, ppos); +out: + return ret; } #endif /* CONFIG_SYSCTL */ @@ -527,7 +551,8 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) break; case CPU_ONLINE: case CPU_ONLINE_FROZEN: - err = watchdog_enable(hotcpu); + if (watchdog_enabled) + err = watchdog_enable(hotcpu); break; #ifdef CONFIG_HOTPLUG_CPU case CPU_UP_CANCELED: @@ -540,27 +565,29 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) break; #endif /* CONFIG_HOTPLUG_CPU */ } - return notifier_from_errno(err); + + /* + * hardlockup and softlockup are not important enough + * to block cpu bring up. Just always succeed and + * rely on printk output to flag problems. + */ + return NOTIFY_OK; } static struct notifier_block __cpuinitdata cpu_nfb = { .notifier_call = cpu_callback }; -static int __init spawn_watchdog_task(void) +void __init lockup_detector_init(void) { void *cpu = (void *)(long)smp_processor_id(); int err; - if (no_watchdog) - return 0; - err = cpu_callback(&cpu_nfb, CPU_UP_PREPARE, cpu); WARN_ON(notifier_to_errno(err)); cpu_callback(&cpu_nfb, CPU_ONLINE, cpu); register_cpu_notifier(&cpu_nfb); - return 0; + return; } -early_initcall(spawn_watchdog_task); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 90db1bd1a97..e3378e8d3a5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -79,7 +79,9 @@ enum { MAX_IDLE_WORKERS_RATIO = 4, /* 1/4 of busy can be idle */ IDLE_WORKER_TIMEOUT = 300 * HZ, /* keep idle ones for 5 mins */ - MAYDAY_INITIAL_TIMEOUT = HZ / 100, /* call for help after 10ms */ + MAYDAY_INITIAL_TIMEOUT = HZ / 100 >= 2 ? HZ / 100 : 2, + /* call for help after 10ms + (min two ticks) */ MAYDAY_INTERVAL = HZ / 10, /* and then every 100ms */ CREATE_COOLDOWN = HZ, /* time to breath after fail */ TRUSTEE_COOLDOWN = HZ / 10, /* for trustee draining */ @@ -249,10 +251,12 @@ struct workqueue_struct *system_wq __read_mostly; struct workqueue_struct *system_long_wq __read_mostly; struct workqueue_struct *system_nrt_wq __read_mostly; struct workqueue_struct *system_unbound_wq __read_mostly; +struct workqueue_struct *system_freezable_wq __read_mostly; EXPORT_SYMBOL_GPL(system_wq); EXPORT_SYMBOL_GPL(system_long_wq); EXPORT_SYMBOL_GPL(system_nrt_wq); EXPORT_SYMBOL_GPL(system_unbound_wq); +EXPORT_SYMBOL_GPL(system_freezable_wq); #define CREATE_TRACE_POINTS #include <trace/events/workqueue.h> @@ -314,6 +318,11 @@ static inline int __next_wq_cpu(int cpu, const struct cpumask *mask, static struct debug_obj_descr work_debug_descr; +static void *work_debug_hint(void *addr) +{ + return ((struct work_struct *) addr)->func; +} + /* * fixup_init is called when: * - an active object is initialized @@ -385,6 +394,7 @@ static int work_fixup_free(void *addr, enum debug_obj_state state) static struct debug_obj_descr work_debug_descr = { .name = "work_struct", + .debug_hint = work_debug_hint, .fixup_init = work_fixup_init, .fixup_activate = work_fixup_activate, .fixup_free = work_fixup_free, @@ -661,7 +671,7 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu) { struct worker *worker = kthread_data(task); - if (likely(!(worker->flags & WORKER_NOT_RUNNING))) + if (!(worker->flags & WORKER_NOT_RUNNING)) atomic_inc(get_gcwq_nr_running(cpu)); } @@ -687,7 +697,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task, struct global_cwq *gcwq = get_gcwq(cpu); atomic_t *nr_running = get_gcwq_nr_running(cpu); - if (unlikely(worker->flags & WORKER_NOT_RUNNING)) + if (worker->flags & WORKER_NOT_RUNNING) return NULL; /* this can only happen on the local cpu */ @@ -768,7 +778,11 @@ static inline void worker_clr_flags(struct worker *worker, unsigned int flags) worker->flags &= ~flags; - /* if transitioning out of NOT_RUNNING, increment nr_running */ + /* + * If transitioning out of NOT_RUNNING, increment nr_running. Note + * that the nested NOT_RUNNING is not a noop. NOT_RUNNING is mask + * of multiple flags, not a single flag. + */ if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING)) if (!(worker->flags & WORKER_NOT_RUNNING)) atomic_inc(get_gcwq_nr_running(gcwq->cpu)); @@ -932,6 +946,38 @@ static void insert_work(struct cpu_workqueue_struct *cwq, wake_up_worker(gcwq); } +/* + * Test whether @work is being queued from another work executing on the + * same workqueue. This is rather expensive and should only be used from + * cold paths. + */ +static bool is_chained_work(struct workqueue_struct *wq) +{ + unsigned long flags; + unsigned int cpu; + + for_each_gcwq_cpu(cpu) { + struct global_cwq *gcwq = get_gcwq(cpu); + struct worker *worker; + struct hlist_node *pos; + int i; + + spin_lock_irqsave(&gcwq->lock, flags); + for_each_busy_worker(worker, i, pos, gcwq) { + if (worker->task != current) + continue; + spin_unlock_irqrestore(&gcwq->lock, flags); + /* + * I'm @worker, no locking necessary. See if @work + * is headed to the same workqueue. + */ + return worker->current_cwq->wq == wq; + } + spin_unlock_irqrestore(&gcwq->lock, flags); + } + return false; +} + static void __queue_work(unsigned int cpu, struct workqueue_struct *wq, struct work_struct *work) { @@ -943,7 +989,9 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq, debug_work_activate(work); - if (WARN_ON_ONCE(wq->flags & WQ_DYING)) + /* if dying, only works from the same workqueue are allowed */ + if (unlikely(wq->flags & WQ_DYING) && + WARN_ON_ONCE(!is_chained_work(wq))) return; /* determine gcwq to use */ @@ -1243,8 +1291,14 @@ __acquires(&gcwq->lock) return true; spin_unlock_irq(&gcwq->lock); - /* CPU has come up inbetween, retry migration */ + /* + * We've raced with CPU hot[un]plug. Give it a breather + * and retry migration. cond_resched() is required here; + * otherwise, we might deadlock against cpu_stop trying to + * bring down the CPU on non-preemptive kernel. + */ cpu_relax(); + cond_resched(); } } @@ -1318,8 +1372,10 @@ static struct worker *create_worker(struct global_cwq *gcwq, bool bind) worker->id = id; if (!on_unbound_cpu) - worker->task = kthread_create(worker_thread, worker, - "kworker/%u:%d", gcwq->cpu, id); + worker->task = kthread_create_on_node(worker_thread, + worker, + cpu_to_node(gcwq->cpu), + "kworker/%u:%d", gcwq->cpu, id); else worker->task = kthread_create(worker_thread, worker, "kworker/u:%d", id); @@ -1806,7 +1862,7 @@ __acquires(&gcwq->lock) spin_unlock_irq(&gcwq->lock); work_clear_pending(work); - lock_map_acquire(&cwq->wq->lockdep_map); + lock_map_acquire_read(&cwq->wq->lockdep_map); lock_map_acquire(&lockdep_map); trace_workqueue_execute_start(work); f(work); @@ -2009,6 +2065,15 @@ repeat: move_linked_works(work, scheduled, &n); process_scheduled_works(rescuer); + + /* + * Leave this gcwq. If keep_working() is %true, notify a + * regular worker; otherwise, we end up with 0 concurrency + * and stalling the execution. + */ + if (keep_working(gcwq)) + wake_up_worker(gcwq); + spin_unlock_irq(&gcwq->lock); } @@ -2350,8 +2415,18 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr, insert_wq_barrier(cwq, barr, work, worker); spin_unlock_irq(&gcwq->lock); - lock_map_acquire(&cwq->wq->lockdep_map); + /* + * If @max_active is 1 or rescuer is in use, flushing another work + * item on the same workqueue may lead to deadlock. Make sure the + * flusher is not running on the same workqueue by verifying write + * access. + */ + if (cwq->wq->saved_max_active == 1 || cwq->wq->flags & WQ_RESCUER) + lock_map_acquire(&cwq->wq->lockdep_map); + else + lock_map_acquire_read(&cwq->wq->lockdep_map); lock_map_release(&cwq->wq->lockdep_map); + return true; already_gone: spin_unlock_irq(&gcwq->lock); @@ -2908,7 +2983,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *name, */ spin_lock(&workqueue_lock); - if (workqueue_freezing && wq->flags & WQ_FREEZEABLE) + if (workqueue_freezing && wq->flags & WQ_FREEZABLE) for_each_cwq_cpu(cpu, wq) get_cwq(cpu, wq)->max_active = 0; @@ -2936,11 +3011,35 @@ EXPORT_SYMBOL_GPL(__alloc_workqueue_key); */ void destroy_workqueue(struct workqueue_struct *wq) { + unsigned int flush_cnt = 0; unsigned int cpu; + /* + * Mark @wq dying and drain all pending works. Once WQ_DYING is + * set, only chain queueing is allowed. IOW, only currently + * pending or running work items on @wq can queue further work + * items on it. @wq is flushed repeatedly until it becomes empty. + * The number of flushing is detemined by the depth of chaining and + * should be relatively short. Whine if it takes too long. + */ wq->flags |= WQ_DYING; +reflush: flush_workqueue(wq); + for_each_cwq_cpu(cpu, wq) { + struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); + + if (!cwq->nr_active && list_empty(&cwq->delayed_works)) + continue; + + if (++flush_cnt == 10 || + (flush_cnt % 100 == 0 && flush_cnt <= 1000)) + printk(KERN_WARNING "workqueue %s: flush on " + "destruction isn't complete after %u tries\n", + wq->name, flush_cnt); + goto reflush; + } + /* * wq list is used to freeze wq, remove from list after * flushing is complete in case freeze races us. @@ -2996,7 +3095,7 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active) spin_lock_irq(&gcwq->lock); - if (!(wq->flags & WQ_FREEZEABLE) || + if (!(wq->flags & WQ_FREEZABLE) || !(gcwq->flags & GCWQ_FREEZING)) get_cwq(gcwq->cpu, wq)->max_active = max_active; @@ -3246,7 +3345,7 @@ static int __cpuinit trustee_thread(void *__gcwq) * want to get it over with ASAP - spam rescuers, wake up as * many idlers as necessary and create new ones till the * worklist is empty. Note that if the gcwq is frozen, there - * may be frozen works in freezeable cwqs. Don't declare + * may be frozen works in freezable cwqs. Don't declare * completion while frozen. */ while (gcwq->nr_workers != gcwq->nr_idle || @@ -3504,9 +3603,9 @@ EXPORT_SYMBOL_GPL(work_on_cpu); /** * freeze_workqueues_begin - begin freezing workqueues * - * Start freezing workqueues. After this function returns, all - * freezeable workqueues will queue new works to their frozen_works - * list instead of gcwq->worklist. + * Start freezing workqueues. After this function returns, all freezable + * workqueues will queue new works to their frozen_works list instead of + * gcwq->worklist. * * CONTEXT: * Grabs and releases workqueue_lock and gcwq->lock's. @@ -3532,7 +3631,7 @@ void freeze_workqueues_begin(void) list_for_each_entry(wq, &workqueues, list) { struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); - if (cwq && wq->flags & WQ_FREEZEABLE) + if (cwq && wq->flags & WQ_FREEZABLE) cwq->max_active = 0; } @@ -3543,7 +3642,7 @@ void freeze_workqueues_begin(void) } /** - * freeze_workqueues_busy - are freezeable workqueues still busy? + * freeze_workqueues_busy - are freezable workqueues still busy? * * Check whether freezing is complete. This function must be called * between freeze_workqueues_begin() and thaw_workqueues(). @@ -3552,8 +3651,8 @@ void freeze_workqueues_begin(void) * Grabs and releases workqueue_lock. * * RETURNS: - * %true if some freezeable workqueues are still busy. %false if - * freezing is complete. + * %true if some freezable workqueues are still busy. %false if freezing + * is complete. */ bool freeze_workqueues_busy(void) { @@ -3573,7 +3672,7 @@ bool freeze_workqueues_busy(void) list_for_each_entry(wq, &workqueues, list) { struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); - if (!cwq || !(wq->flags & WQ_FREEZEABLE)) + if (!cwq || !(wq->flags & WQ_FREEZABLE)) continue; BUG_ON(cwq->nr_active < 0); @@ -3618,7 +3717,7 @@ void thaw_workqueues(void) list_for_each_entry(wq, &workqueues, list) { struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); - if (!cwq || !(wq->flags & WQ_FREEZEABLE)) + if (!cwq || !(wq->flags & WQ_FREEZABLE)) continue; /* restore max_active and repopulate worklist */ @@ -3692,7 +3791,10 @@ static int __init init_workqueues(void) system_nrt_wq = alloc_workqueue("events_nrt", WQ_NON_REENTRANT, 0); system_unbound_wq = alloc_workqueue("events_unbound", WQ_UNBOUND, WQ_UNBOUND_MAX_ACTIVE); - BUG_ON(!system_wq || !system_long_wq || !system_nrt_wq); + system_freezable_wq = alloc_workqueue("events_freezable", + WQ_FREEZABLE, 0); + BUG_ON(!system_wq || !system_long_wq || !system_nrt_wq || + !system_unbound_wq || !system_freezable_wq); return 0; } early_initcall(init_workqueues); |