diff options
author | David S. Miller <davem@davemloft.net> | 2009-12-05 15:22:26 -0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2009-12-05 15:22:26 -0800 |
commit | 28b4d5cc17c20786848cdc07b7ea237a309776bb (patch) | |
tree | bae406a4b17229dcce7c11be5073f7a67665e477 /kernel | |
parent | d29cecda036f251aee4947f47eea0fe9ed8cc931 (diff) | |
parent | 96fa2b508d2d3fe040cf4ef2fffb955f0a537ea1 (diff) |
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts:
drivers/net/pcmcia/fmvj18x_cs.c
drivers/net/pcmcia/nmclan_cs.c
drivers/net/pcmcia/xirc2ps_cs.c
drivers/net/wireless/ray_cs.c
Diffstat (limited to 'kernel')
36 files changed, 2135 insertions, 825 deletions
diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks new file mode 100644 index 00000000000..88c92fb4461 --- /dev/null +++ b/kernel/Kconfig.locks @@ -0,0 +1,202 @@ +# +# The ARCH_INLINE foo is necessary because select ignores "depends on" +# +config ARCH_INLINE_SPIN_TRYLOCK + bool + +config ARCH_INLINE_SPIN_TRYLOCK_BH + bool + +config ARCH_INLINE_SPIN_LOCK + bool + +config ARCH_INLINE_SPIN_LOCK_BH + bool + +config ARCH_INLINE_SPIN_LOCK_IRQ + bool + +config ARCH_INLINE_SPIN_LOCK_IRQSAVE + bool + +config ARCH_INLINE_SPIN_UNLOCK + bool + +config ARCH_INLINE_SPIN_UNLOCK_BH + bool + +config ARCH_INLINE_SPIN_UNLOCK_IRQ + bool + +config ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE + bool + + +config ARCH_INLINE_READ_TRYLOCK + bool + +config ARCH_INLINE_READ_LOCK + bool + +config ARCH_INLINE_READ_LOCK_BH + bool + +config ARCH_INLINE_READ_LOCK_IRQ + bool + +config ARCH_INLINE_READ_LOCK_IRQSAVE + bool + +config ARCH_INLINE_READ_UNLOCK + bool + +config ARCH_INLINE_READ_UNLOCK_BH + bool + +config ARCH_INLINE_READ_UNLOCK_IRQ + bool + +config ARCH_INLINE_READ_UNLOCK_IRQRESTORE + bool + + +config ARCH_INLINE_WRITE_TRYLOCK + bool + +config ARCH_INLINE_WRITE_LOCK + bool + +config ARCH_INLINE_WRITE_LOCK_BH + bool + +config ARCH_INLINE_WRITE_LOCK_IRQ + bool + +config ARCH_INLINE_WRITE_LOCK_IRQSAVE + bool + +config ARCH_INLINE_WRITE_UNLOCK + bool + +config ARCH_INLINE_WRITE_UNLOCK_BH + bool + +config ARCH_INLINE_WRITE_UNLOCK_IRQ + bool + +config ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE + bool + +# +# lock_* functions are inlined when: +# - DEBUG_SPINLOCK=n and GENERIC_LOCKBREAK=n and ARCH_INLINE_*LOCK=y +# +# trylock_* functions are inlined when: +# - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y +# +# unlock and unlock_irq functions are inlined when: +# - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y +# or +# - DEBUG_SPINLOCK=n and PREEMPT=n +# +# unlock_bh and unlock_irqrestore functions are inlined when: +# - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y +# + +config INLINE_SPIN_TRYLOCK + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_TRYLOCK + +config INLINE_SPIN_TRYLOCK_BH + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_TRYLOCK_BH + +config INLINE_SPIN_LOCK + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_SPIN_LOCK + +config INLINE_SPIN_LOCK_BH + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_SPIN_LOCK_BH + +config INLINE_SPIN_LOCK_IRQ + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_SPIN_LOCK_IRQ + +config INLINE_SPIN_LOCK_IRQSAVE + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_SPIN_LOCK_IRQSAVE + +config INLINE_SPIN_UNLOCK + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_SPIN_UNLOCK) + +config INLINE_SPIN_UNLOCK_BH + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_UNLOCK_BH + +config INLINE_SPIN_UNLOCK_IRQ + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_SPIN_UNLOCK_BH) + +config INLINE_SPIN_UNLOCK_IRQRESTORE + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE + + +config INLINE_READ_TRYLOCK + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_TRYLOCK + +config INLINE_READ_LOCK + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_READ_LOCK + +config INLINE_READ_LOCK_BH + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_READ_LOCK_BH + +config INLINE_READ_LOCK_IRQ + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_READ_LOCK_IRQ + +config INLINE_READ_LOCK_IRQSAVE + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_READ_LOCK_IRQSAVE + +config INLINE_READ_UNLOCK + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_READ_UNLOCK) + +config INLINE_READ_UNLOCK_BH + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_UNLOCK_BH + +config INLINE_READ_UNLOCK_IRQ + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_READ_UNLOCK_BH) + +config INLINE_READ_UNLOCK_IRQRESTORE + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_UNLOCK_IRQRESTORE + + +config INLINE_WRITE_TRYLOCK + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_TRYLOCK + +config INLINE_WRITE_LOCK + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_WRITE_LOCK + +config INLINE_WRITE_LOCK_BH + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_WRITE_LOCK_BH + +config INLINE_WRITE_LOCK_IRQ + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_WRITE_LOCK_IRQ + +config INLINE_WRITE_LOCK_IRQSAVE + def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \ + ARCH_INLINE_WRITE_LOCK_IRQSAVE + +config INLINE_WRITE_UNLOCK + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_WRITE_UNLOCK) + +config INLINE_WRITE_UNLOCK_BH + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_BH + +config INLINE_WRITE_UNLOCK_IRQ + def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_WRITE_UNLOCK_BH) + +config INLINE_WRITE_UNLOCK_IRQRESTORE + def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE + +config MUTEX_SPIN_ON_OWNER + def_bool SMP && !DEBUG_MUTEXES && !HAVE_DEFAULT_NO_SPIN_MUTEXES diff --git a/kernel/Makefile b/kernel/Makefile index d7c13d249b2..dcf6789bf54 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -82,6 +82,7 @@ obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o obj-$(CONFIG_TREE_RCU) += rcutree.o obj-$(CONFIG_TREE_PREEMPT_RCU) += rcutree.o obj-$(CONFIG_TREE_RCU_TRACE) += rcutree_trace.o +obj-$(CONFIG_TINY_RCU) += rcutiny.o obj-$(CONFIG_RELAY) += relay.o obj-$(CONFIG_SYSCTL) += utsname_sysctl.o obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o diff --git a/kernel/capability.c b/kernel/capability.c index 4e17041963f..7f876e60521 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -29,7 +29,6 @@ EXPORT_SYMBOL(__cap_empty_set); EXPORT_SYMBOL(__cap_full_set); EXPORT_SYMBOL(__cap_init_eff_set); -#ifdef CONFIG_SECURITY_FILE_CAPABILITIES int file_caps_enabled = 1; static int __init file_caps_disable(char *str) @@ -38,7 +37,6 @@ static int __init file_caps_disable(char *str) return 1; } __setup("no_file_caps", file_caps_disable); -#endif /* * More recent versions of libcap are available from: @@ -169,8 +167,8 @@ SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr) kernel_cap_t pE, pI, pP; ret = cap_validate_magic(header, &tocopy); - if (ret != 0) - return ret; + if ((dataptr == NULL) || (ret != 0)) + return ((dataptr == NULL) && (ret == -EINVAL)) ? 0 : ret; if (get_user(pid, &header->pid)) return -EFAULT; @@ -238,7 +236,7 @@ SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr) SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data) { struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S]; - unsigned i, tocopy; + unsigned i, tocopy, copybytes; kernel_cap_t inheritable, permitted, effective; struct cred *new; int ret; @@ -255,8 +253,11 @@ SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data) if (pid != 0 && pid != task_pid_vnr(current)) return -EPERM; - if (copy_from_user(&kdata, data, - tocopy * sizeof(struct __user_cap_data_struct))) + copybytes = tocopy * sizeof(struct __user_cap_data_struct); + if (copybytes > sizeof(kdata)) + return -EFAULT; + + if (copy_from_user(&kdata, data, copybytes)) return -EFAULT; for (i = 0; i < tocopy; i++) { diff --git a/kernel/hung_task.c b/kernel/hung_task.c index d4e84174740..0c642d51aac 100644 --- a/kernel/hung_task.c +++ b/kernel/hung_task.c @@ -144,7 +144,7 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout) rcu_read_lock(); do_each_thread(g, t) { - if (!--max_count) + if (!max_count--) goto unlock; if (!--batch_count) { batch_count = HUNG_TASK_BATCHING; diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index c1660194d11..ba566c261ad 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -166,11 +166,11 @@ int set_irq_data(unsigned int irq, void *data) EXPORT_SYMBOL(set_irq_data); /** - * set_irq_data - set irq type data for an irq + * set_irq_msi - set MSI descriptor data for an irq * @irq: Interrupt number * @entry: Pointer to MSI descriptor data * - * Set the hardware irq controller data for an irq + * Set the MSI descriptor entry for an irq */ int set_irq_msi(unsigned int irq, struct msi_desc *entry) { @@ -590,7 +590,7 @@ out_unlock: } /** - * handle_percpu_IRQ - Per CPU local irq handler + * handle_percpu_irq - Per CPU local irq handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 692363dd591..0832145fea9 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -136,7 +136,7 @@ out: static int default_affinity_open(struct inode *inode, struct file *file) { - return single_open(file, default_affinity_show, NULL); + return single_open(file, default_affinity_show, PDE(inode)->data); } static const struct file_operations default_affinity_proc_fops = { @@ -148,18 +148,28 @@ static const struct file_operations default_affinity_proc_fops = { }; #endif -static int irq_spurious_read(char *page, char **start, off_t off, - int count, int *eof, void *data) +static int irq_spurious_proc_show(struct seq_file *m, void *v) { - struct irq_desc *desc = irq_to_desc((long) data); - return sprintf(page, "count %u\n" - "unhandled %u\n" - "last_unhandled %u ms\n", - desc->irq_count, - desc->irqs_unhandled, - jiffies_to_msecs(desc->last_unhandled)); + struct irq_desc *desc = irq_to_desc((long) m->private); + + seq_printf(m, "count %u\n" "unhandled %u\n" "last_unhandled %u ms\n", + desc->irq_count, desc->irqs_unhandled, + jiffies_to_msecs(desc->last_unhandled)); + return 0; +} + +static int irq_spurious_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, irq_spurious_proc_show, NULL); } +static const struct file_operations irq_spurious_proc_fops = { + .open = irq_spurious_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + #define MAX_NAMELEN 128 static int name_unique(unsigned int irq, struct irqaction *new_action) @@ -204,7 +214,6 @@ void register_handler_proc(unsigned int irq, struct irqaction *action) void register_irq_proc(unsigned int irq, struct irq_desc *desc) { char name [MAX_NAMELEN]; - struct proc_dir_entry *entry; if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir) return; @@ -214,6 +223,8 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) /* create /proc/irq/1234 */ desc->dir = proc_mkdir(name, root_irq_dir); + if (!desc->dir) + return; #ifdef CONFIG_SMP /* create /proc/irq/<irq>/smp_affinity */ @@ -221,11 +232,8 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) &irq_affinity_proc_fops, (void *)(long)irq); #endif - entry = create_proc_entry("spurious", 0444, desc->dir); - if (entry) { - entry->data = (void *)(long)irq; - entry->read_proc = irq_spurious_read; - } + proc_create_data("spurious", 0444, desc->dir, + &irq_spurious_proc_fops, (void *)(long)irq); } #undef MAX_NAMELEN diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index bd7273e6282..22b0a6eedf2 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -104,7 +104,7 @@ static int misrouted_irq(int irq) return ok; } -static void poll_all_shared_irqs(void) +static void poll_spurious_irqs(unsigned long dummy) { struct irq_desc *desc; int i; @@ -125,23 +125,11 @@ static void poll_all_shared_irqs(void) try_one_irq(i, desc); local_irq_enable(); } -} - -static void poll_spurious_irqs(unsigned long dummy) -{ - poll_all_shared_irqs(); mod_timer(&poll_spurious_irq_timer, jiffies + POLL_SPURIOUS_IRQ_INTERVAL); } -#ifdef CONFIG_DEBUG_SHIRQ -void debug_poll_all_shared_irqs(void) -{ - poll_all_shared_irqs(); -} -#endif - /* * If 99,900 of the previous 100,000 interrupts have not been handled * then assume that the IRQ is stuck in some manner. Drop a diagnostic diff --git a/kernel/kmod.c b/kernel/kmod.c index 9fcb53a11f8..25b10319036 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -80,16 +80,16 @@ int __request_module(bool wait, const char *fmt, ...) #define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */ static int kmod_loop_msg; - ret = security_kernel_module_request(); - if (ret) - return ret; - va_start(args, fmt); ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args); va_end(args); if (ret >= MODULE_NAME_LEN) return -ENAMETOOLONG; + ret = security_kernel_module_request(module_name); + if (ret) + return ret; + /* If modprobe needs a service that is in a module, we get a recursive * loop. Limit the number of running kmod threads to max_threads/2 or * MAX_KMOD_CONCURRENT, whichever is the smaller. A cleaner method diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 5240d75f4c6..1494e85b35f 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1014,9 +1014,9 @@ int __kprobes register_kretprobe(struct kretprobe *rp) /* Pre-allocate memory for max kretprobe instances */ if (rp->maxactive <= 0) { #ifdef CONFIG_PREEMPT - rp->maxactive = max(10, 2 * NR_CPUS); + rp->maxactive = max(10, 2 * num_possible_cpus()); #else - rp->maxactive = NR_CPUS; + rp->maxactive = num_possible_cpus(); #endif } spin_lock_init(&rp->lock); diff --git a/kernel/module.c b/kernel/module.c index 8b7d8805819..5842a71cf05 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1187,7 +1187,8 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect, /* Count loaded sections and allocate structures */ for (i = 0; i < nsect; i++) - if (sechdrs[i].sh_flags & SHF_ALLOC) + if (sechdrs[i].sh_flags & SHF_ALLOC + && sechdrs[i].sh_size) nloaded++; size[0] = ALIGN(sizeof(*sect_attrs) + nloaded * sizeof(sect_attrs->attrs[0]), @@ -1207,6 +1208,8 @@ static void add_sect_attrs(struct module *mod, unsigned int nsect, for (i = 0; i < nsect; i++) { if (! (sechdrs[i].sh_flags & SHF_ALLOC)) continue; + if (!sechdrs[i].sh_size) + continue; sattr->address = sechdrs[i].sh_addr; sattr->name = kstrdup(secstrings + sechdrs[i].sh_name, GFP_KERNEL); diff --git a/kernel/mutex.c b/kernel/mutex.c index 947b3ad551f..632f04c57d8 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -148,8 +148,8 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, preempt_disable(); mutex_acquire(&lock->dep_map, subclass, 0, ip); -#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) && \ - !defined(CONFIG_HAVE_DEFAULT_NO_SPIN_MUTEXES) + +#ifdef CONFIG_MUTEX_SPIN_ON_OWNER /* * Optimistic spinning. * diff --git a/kernel/printk.c b/kernel/printk.c index f38b07f78a4..b5ac4d99c66 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -33,6 +33,7 @@ #include <linux/bootmem.h> #include <linux/syscalls.h> #include <linux/kexec.h> +#include <linux/ratelimit.h> #include <asm/uaccess.h> @@ -1376,11 +1377,11 @@ late_initcall(disable_boot_consoles); */ DEFINE_RATELIMIT_STATE(printk_ratelimit_state, 5 * HZ, 10); -int printk_ratelimit(void) +int __printk_ratelimit(const char *func) { - return __ratelimit(&printk_ratelimit_state); + return ___ratelimit(&printk_ratelimit_state, func); } -EXPORT_SYMBOL(printk_ratelimit); +EXPORT_SYMBOL(__printk_ratelimit); /** * printk_timed_ratelimit - caller-controlled printk ratelimiting diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index 400183346ad..9b7fd472387 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -44,7 +44,6 @@ #include <linux/cpu.h> #include <linux/mutex.h> #include <linux/module.h> -#include <linux/kernel_stat.h> #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key rcu_lock_key; @@ -53,8 +52,6 @@ struct lockdep_map rcu_lock_map = EXPORT_SYMBOL_GPL(rcu_lock_map); #endif -int rcu_scheduler_active __read_mostly; - /* * Awaken the corresponding synchronize_rcu() instance now that a * grace period has elapsed. @@ -66,122 +63,3 @@ void wakeme_after_rcu(struct rcu_head *head) rcu = container_of(head, struct rcu_synchronize, head); complete(&rcu->completion); } - -#ifdef CONFIG_TREE_PREEMPT_RCU - -/** - * synchronize_rcu - wait until a grace period has elapsed. - * - * Control will return to the caller some time after a full grace - * period has elapsed, in other words after all currently executing RCU - * read-side critical sections have completed. RCU read-side critical - * sections are delimited by rcu_read_lock() and rcu_read_unlock(), - * and may be nested. - */ -void synchronize_rcu(void) -{ - struct rcu_synchronize rcu; - - if (!rcu_scheduler_active) - return; - - init_completion(&rcu.completion); - /* Will wake me after RCU finished. */ - call_rcu(&rcu.head, wakeme_after_rcu); - /* Wait for it. */ - wait_for_completion(&rcu.completion); -} -EXPORT_SYMBOL_GPL(synchronize_rcu); - -#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ - -/** - * synchronize_sched - wait until an rcu-sched grace period has elapsed. - * - * Control will return to the caller some time after a full rcu-sched - * grace period has elapsed, in other words after all currently executing - * rcu-sched read-side critical sections have completed. These read-side - * critical sections are delimited by rcu_read_lock_sched() and - * rcu_read_unlock_sched(), and may be nested. Note that preempt_disable(), - * local_irq_disable(), and so on may be used in place of - * rcu_read_lock_sched(). - * - * This means that all preempt_disable code sequences, including NMI and - * hardware-interrupt handlers, in progress on entry will have completed - * before this primitive returns. However, this does not guarantee that - * softirq handlers will have completed, since in some kernels, these - * handlers can run in process context, and can block. - * - * This primitive provides the guarantees made by the (now removed) - * synchronize_kernel() API. In contrast, synchronize_rcu() only - * guarantees that rcu_read_lock() sections will have completed. - * In "classic RCU", these two guarantees happen to be one and - * the same, but can differ in realtime RCU implementations. - */ -void synchronize_sched(void) -{ - struct rcu_synchronize rcu; - - if (rcu_blocking_is_gp()) - return; - - init_completion(&rcu.completion); - /* Will wake me after RCU finished. */ - call_rcu_sched(&rcu.head, wakeme_after_rcu); - /* Wait for it. */ - wait_for_completion(&rcu.completion); -} -EXPORT_SYMBOL_GPL(synchronize_sched); - -/** - * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed. - * - * Control will return to the caller some time after a full rcu_bh grace - * period has elapsed, in other words after all currently executing rcu_bh - * read-side critical sections have completed. RCU read-side critical - * sections are delimited by rcu_read_lock_bh() and rcu_read_unlock_bh(), - * and may be nested. - */ -void synchronize_rcu_bh(void) -{ - struct rcu_synchronize rcu; - - if (rcu_blocking_is_gp()) - return; - - init_completion(&rcu.completion); - /* Will wake me after RCU finished. */ - call_rcu_bh(&rcu.head, wakeme_after_rcu); - /* Wait for it. */ - wait_for_completion(&rcu.completion); -} -EXPORT_SYMBOL_GPL(synchronize_rcu_bh); - -static int __cpuinit rcu_barrier_cpu_hotplug(struct notifier_block *self, - unsigned long action, void *hcpu) -{ - return rcu_cpu_notify(self, action, hcpu); -} - -void __init rcu_init(void) -{ - int i; - - __rcu_init(); - cpu_notifier(rcu_barrier_cpu_hotplug, 0); - - /* - * We don't need protection against CPU-hotplug here because - * this is called early in boot, before either interrupts - * or the scheduler are operational. - */ - for_each_online_cpu(i) - rcu_barrier_cpu_hotplug(NULL, CPU_UP_PREPARE, (void *)(long)i); -} - -void rcu_scheduler_starting(void) -{ - WARN_ON(num_online_cpus() != 1); - WARN_ON(nr_context_switches() > 0); - rcu_scheduler_active = 1; -} diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c new file mode 100644 index 00000000000..9f6d9ff2572 --- /dev/null +++ b/kernel/rcutiny.c @@ -0,0 +1,282 @@ +/* + * Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition. + * + * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright IBM Corporation, 2008 + * + * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com> + * + * For detailed explanation of Read-Copy Update mechanism see - + * Documentation/RCU + */ +#include <linux/moduleparam.h> +#include <linux/completion.h> +#include <linux/interrupt.h> +#include <linux/notifier.h> +#include <linux/rcupdate.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/types.h> +#include <linux/init.h> +#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_ctrlblk = { + .donetail = &rcu_ctrlblk.rcucblist, + .curtail = &rcu_ctrlblk.rcucblist, +}; + +static struct rcu_ctrlblk rcu_bh_ctrlblk = { + .donetail = &rcu_bh_ctrlblk.rcucblist, + .curtail = &rcu_bh_ctrlblk.rcucblist, +}; + +#ifdef CONFIG_NO_HZ + +static long rcu_dynticks_nesting = 1; + +/* + * Enter dynticks-idle mode, which is an extended quiescent state + * if we have fully entered that mode (i.e., if the new value of + * dynticks_nesting is zero). + */ +void rcu_enter_nohz(void) +{ + if (--rcu_dynticks_nesting == 0) + rcu_sched_qs(0); /* implies rcu_bh_qsctr_inc(0) */ +} + +/* + * Exit dynticks-idle mode, so that we are no longer in an extended + * quiescent state. + */ +void rcu_exit_nohz(void) +{ + rcu_dynticks_nesting++; +} + +#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 + * 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; +} + +/* + * 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) +{ + if (rcu_qsctr_help(&rcu_ctrlblk) + rcu_qsctr_help(&rcu_bh_ctrlblk)) + raise_softirq(RCU_SOFTIRQ); +} + +/* + * Record an rcu_bh quiescent state. + */ +void rcu_bh_qs(int cpu) +{ + if (rcu_qsctr_help(&rcu_bh_ctrlblk)) + raise_softirq(RCU_SOFTIRQ); +} + +/* + * Check to see if the scheduling-clock interrupt came from an extended + * quiescent state, and, if so, tell RCU about it. + */ +void rcu_check_callbacks(int cpu, int user) +{ + if (user || + (idle_cpu(cpu) && + |