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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 08:27:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 08:27:54 -0700
commitb8ae30ee26d379db436b0b8c8c3ff1b52f69e5d1 (patch)
tree506aa0b4bdbf90f61e7e9261c7db90aa1452dcce /kernel
parent4d7b4ac22fbec1a03206c6cde353f2fd6942f828 (diff)
parent9c6f7e43b4e02c161b53e97ba913855246876c61 (diff)
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (49 commits) stop_machine: Move local variable closer to the usage site in cpu_stop_cpu_callback() sched, wait: Use wrapper functions sched: Remove a stale comment ondemand: Make the iowait-is-busy time a sysfs tunable ondemand: Solve a big performance issue by counting IOWAIT time as busy sched: Intoduce get_cpu_iowait_time_us() sched: Eliminate the ts->idle_lastupdate field sched: Fold updating of the last_update_time_info into update_ts_time_stats() sched: Update the idle statistics in get_cpu_idle_time_us() sched: Introduce a function to update the idle statistics sched: Add a comment to get_cpu_idle_time_us() cpu_stop: add dummy implementation for UP sched: Remove rq argument to the tracepoints rcu: need barrier() in UP synchronize_sched_expedited() sched: correctly place paranioa memory barriers in synchronize_sched_expedited() sched: kill paranoia check in synchronize_sched_expedited() sched: replace migration_thread with cpu_stop stop_machine: reimplement using cpu_stop cpu_stop: implement stop_cpu[s]() sched: Fix select_idle_sibling() logic in select_task_rq_fair() ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile2
-rw-r--r--kernel/capability.c1
-rw-r--r--kernel/cgroup.c2
-rw-r--r--kernel/cpu.c26
-rw-r--r--kernel/cpuset.c67
-rw-r--r--kernel/cred-internals.h21
-rw-r--r--kernel/cred.c3
-rw-r--r--kernel/exit.c1
-rw-r--r--kernel/module.c14
-rw-r--r--kernel/rcutorture.c2
-rw-r--r--kernel/sched.c726
-rw-r--r--kernel/sched_debug.c108
-rw-r--r--kernel/sched_fair.c350
-rw-r--r--kernel/sched_features.h55
-rw-r--r--kernel/sched_idletask.c8
-rw-r--r--kernel/sched_rt.c15
-rw-r--r--kernel/stop_machine.c537
-rw-r--r--kernel/time/tick-sched.c84
-rw-r--r--kernel/time/timer_list.c1
-rw-r--r--kernel/trace/ftrace.c3
-rw-r--r--kernel/trace/trace_sched_switch.c5
-rw-r--r--kernel/trace/trace_sched_wakeup.c5
-rw-r--r--kernel/user.c11
23 files changed, 1001 insertions, 1046 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index a987aa1676b..149e18ef1ab 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -68,7 +68,7 @@ obj-$(CONFIG_USER_NS) += user_namespace.o
obj-$(CONFIG_PID_NS) += pid_namespace.o
obj-$(CONFIG_IKCONFIG) += configs.o
obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
-obj-$(CONFIG_STOP_MACHINE) += stop_machine.o
+obj-$(CONFIG_SMP) += stop_machine.o
obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
obj-$(CONFIG_AUDIT) += audit.o auditfilter.o audit_watch.o
obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
diff --git a/kernel/capability.c b/kernel/capability.c
index 9e4697e9b27..2f05303715a 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -15,7 +15,6 @@
#include <linux/syscalls.h>
#include <linux/pid_namespace.h>
#include <asm/uaccess.h>
-#include "cred-internals.h"
/*
* Leveraged for setting/resetting capabilities
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 6d870f2d122..e9ec642932e 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -3016,7 +3016,7 @@ static int cgroup_event_wake(wait_queue_t *wait, unsigned mode,
unsigned long flags = (unsigned long)key;
if (flags & POLLHUP) {
- remove_wait_queue_locked(event->wqh, &event->wait);
+ __remove_wait_queue(event->wqh, &event->wait);
spin_lock(&cgrp->event_list_lock);
list_del(&event->list);
spin_unlock(&cgrp->event_list_lock);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 25bba73b1be..54577757477 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -164,6 +164,7 @@ static inline void check_for_tasks(int cpu)
}
struct take_cpu_down_param {
+ struct task_struct *caller;
unsigned long mod;
void *hcpu;
};
@@ -172,6 +173,7 @@ 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. */
@@ -182,6 +184,8 @@ static int __ref take_cpu_down(void *_param)
raw_notifier_call_chain(&cpu_chain, 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();
@@ -192,10 +196,10 @@ static int __ref take_cpu_down(void *_param)
static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
{
int err, nr_calls = 0;
- cpumask_var_t old_allowed;
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,
};
@@ -206,9 +210,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
if (!cpu_online(cpu))
return -EINVAL;
- if (!alloc_cpumask_var(&old_allowed, GFP_KERNEL))
- return -ENOMEM;
-
cpu_hotplug_begin();
set_cpu_active(cpu, false);
err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
@@ -225,10 +226,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
goto out_release;
}
- /* Ensure that we are not runnable on dying cpu */
- cpumask_copy(old_allowed, &current->cpus_allowed);
- set_cpus_allowed_ptr(current, cpu_active_mask);
-
err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
if (err) {
set_cpu_active(cpu, true);
@@ -237,7 +234,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
hcpu) == NOTIFY_BAD)
BUG();
- goto out_allowed;
+ goto out_release;
}
BUG_ON(cpu_online(cpu));
@@ -255,8 +252,6 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
check_for_tasks(cpu);
-out_allowed:
- set_cpus_allowed_ptr(current, old_allowed);
out_release:
cpu_hotplug_done();
if (!err) {
@@ -264,7 +259,6 @@ out_release:
hcpu) == NOTIFY_BAD)
BUG();
}
- free_cpumask_var(old_allowed);
return err;
}
@@ -272,9 +266,6 @@ int __ref cpu_down(unsigned int cpu)
{
int err;
- err = stop_machine_create();
- if (err)
- return err;
cpu_maps_update_begin();
if (cpu_hotplug_disabled) {
@@ -286,7 +277,6 @@ int __ref cpu_down(unsigned int cpu)
out:
cpu_maps_update_done();
- stop_machine_destroy();
return err;
}
EXPORT_SYMBOL(cpu_down);
@@ -367,9 +357,6 @@ int disable_nonboot_cpus(void)
{
int cpu, first_cpu, error;
- error = stop_machine_create();
- if (error)
- return error;
cpu_maps_update_begin();
first_cpu = cpumask_first(cpu_online_mask);
/*
@@ -400,7 +387,6 @@ int disable_nonboot_cpus(void)
printk(KERN_ERR "Non-boot CPUs are not disabled\n");
}
cpu_maps_update_done();
- stop_machine_destroy();
return error;
}
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index d10946748ec..9a50c5f6e72 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2182,19 +2182,52 @@ void __init cpuset_init_smp(void)
void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
{
mutex_lock(&callback_mutex);
- cpuset_cpus_allowed_locked(tsk, pmask);
+ task_lock(tsk);
+ guarantee_online_cpus(task_cs(tsk), pmask);
+ task_unlock(tsk);
mutex_unlock(&callback_mutex);
}
-/**
- * cpuset_cpus_allowed_locked - return cpus_allowed mask from a tasks cpuset.
- * Must be called with callback_mutex held.
- **/
-void cpuset_cpus_allowed_locked(struct task_struct *tsk, struct cpumask *pmask)
+int cpuset_cpus_allowed_fallback(struct task_struct *tsk)
{
- task_lock(tsk);
- guarantee_online_cpus(task_cs(tsk), pmask);
- task_unlock(tsk);
+ const struct cpuset *cs;
+ int cpu;
+
+ rcu_read_lock();
+ cs = task_cs(tsk);
+ if (cs)
+ cpumask_copy(&tsk->cpus_allowed, cs->cpus_allowed);
+ rcu_read_unlock();
+
+ /*
+ * We own tsk->cpus_allowed, nobody can change it under us.
+ *
+ * But we used cs && cs->cpus_allowed lockless and thus can
+ * race with cgroup_attach_task() or update_cpumask() and get
+ * the wrong tsk->cpus_allowed. However, both cases imply the
+ * subsequent cpuset_change_cpumask()->set_cpus_allowed_ptr()
+ * which takes task_rq_lock().
+ *
+ * If we are called after it dropped the lock we must see all
+ * changes in tsk_cs()->cpus_allowed. Otherwise we can temporary
+ * set any mask even if it is not right from task_cs() pov,
+ * the pending set_cpus_allowed_ptr() will fix things.
+ */
+
+ cpu = cpumask_any_and(&tsk->cpus_allowed, cpu_active_mask);
+ if (cpu >= nr_cpu_ids) {
+ /*
+ * Either tsk->cpus_allowed is wrong (see above) or it
+ * is actually empty. The latter case is only possible
+ * if we are racing with remove_tasks_in_empty_cpuset().
+ * Like above we can temporary set any mask and rely on
+ * set_cpus_allowed_ptr() as synchronization point.
+ */
+ cpumask_copy(&tsk->cpus_allowed, cpu_possible_mask);
+ cpu = cpumask_any(cpu_active_mask);
+ }
+
+ return cpu;
}
void cpuset_init_current_mems_allowed(void)
@@ -2383,22 +2416,6 @@ int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
}
/**
- * cpuset_lock - lock out any changes to cpuset structures
- *
- * The out of memory (oom) code needs to mutex_lock cpusets
- * from being changed while it scans the tasklist looking for a
- * task in an overlapping cpuset. Expose callback_mutex via this
- * cpuset_lock() routine, so the oom code can lock it, before
- * locking the task list. The tasklist_lock is a spinlock, so
- * must be taken inside callback_mutex.
- */
-
-void cpuset_lock(void)
-{
- mutex_lock(&callback_mutex);
-}
-
-/**
* cpuset_unlock - release lock on cpuset changes
*
* Undo the lock taken in a previous cpuset_lock() call.
diff --git a/kernel/cred-internals.h b/kernel/cred-internals.h
deleted file mode 100644
index 2dc4fc2d0bf..00000000000
--- a/kernel/cred-internals.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/* Internal credentials stuff
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public Licence
- * as published by the Free Software Foundation; either version
- * 2 of the Licence, or (at your option) any later version.
- */
-
-/*
- * user.c
- */
-static inline void sched_switch_user(struct task_struct *p)
-{
-#ifdef CONFIG_USER_SCHED
- sched_move_task(p);
-#endif /* CONFIG_USER_SCHED */
-}
-
diff --git a/kernel/cred.c b/kernel/cred.c
index 62af1816c23..8f3672a58a1 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -17,7 +17,6 @@
#include <linux/init_task.h>
#include <linux/security.h>
#include <linux/cn_proc.h>
-#include "cred-internals.h"
#if 0
#define kdebug(FMT, ...) \
@@ -560,8 +559,6 @@ int commit_creds(struct cred *new)
atomic_dec(&old->user->processes);
alter_cred_subscribers(old, -2);
- sched_switch_user(task);
-
/* send notifications */
if (new->uid != old->uid ||
new->euid != old->euid ||
diff --git a/kernel/exit.c b/kernel/exit.c
index 7f2683a10ac..eabca5a73a8 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -55,7 +55,6 @@
#include <asm/unistd.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
-#include "cred-internals.h"
static void exit_mm(struct task_struct * tsk);
diff --git a/kernel/module.c b/kernel/module.c
index b8a1e313448..e2564580f3f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -724,16 +724,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
return -EFAULT;
name[MODULE_NAME_LEN-1] = '\0';
- /* Create stop_machine threads since free_module relies on
- * a non-failing stop_machine call. */
- ret = stop_machine_create();
- if (ret)
- return ret;
-
- if (mutex_lock_interruptible(&module_mutex) != 0) {
- ret = -EINTR;
- goto out_stop;
- }
+ if (mutex_lock_interruptible(&module_mutex) != 0)
+ return -EINTR;
mod = find_module(name);
if (!mod) {
@@ -793,8 +785,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
out:
mutex_unlock(&module_mutex);
-out_stop:
- stop_machine_destroy();
return ret;
}
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 077defb3457..6535ac8bc6a 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -671,7 +671,7 @@ static struct rcu_torture_ops sched_expedited_ops = {
.sync = synchronize_sched_expedited,
.cb_barrier = NULL,
.fqs = rcu_sched_force_quiescent_state,
- .stats = rcu_expedited_torture_stats,
+ .stats = NULL,
.irq_capable = 1,
.name = "sched_expedited"
};
diff --git a/kernel/sched.c b/kernel/sched.c
index 5cd607ec840..1d93cd0ae4d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -55,9 +55,9 @@
#include <linux/cpu.h>
#include <linux/cpuset.h>
#include <linux/percpu.h>
-#include <linux/kthread.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include <linux/stop_machine.h>
#include <linux/sysctl.h>
#include <linux/syscalls.h>
#include <linux/times.h>
@@ -503,8 +503,11 @@ struct rq {
#define CPU_LOAD_IDX_MAX 5
unsigned long cpu_load[CPU_LOAD_IDX_MAX];
#ifdef CONFIG_NO_HZ
+ u64 nohz_stamp;
unsigned char in_nohz_recently;
#endif
+ unsigned int skip_clock_update;
+
/* capture load from *all* tasks on this cpu: */
struct load_weight load;
unsigned long nr_load_updates;
@@ -546,15 +549,13 @@ struct rq {
int post_schedule;
int active_balance;
int push_cpu;
+ struct cpu_stop_work active_balance_work;
/* cpu of this runqueue: */
int cpu;
int online;
unsigned long avg_load_per_task;
- struct task_struct *migration_thread;
- struct list_head migration_queue;
-
u64 rt_avg;
u64 age_stamp;
u64 idle_stamp;
@@ -602,6 +603,13 @@ 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 inline int cpu_of(struct rq *rq)
@@ -636,7 +644,8 @@ static inline int cpu_of(struct rq *rq)
inline void update_rq_clock(struct rq *rq)
{
- rq->clock = sched_clock_cpu(cpu_of(rq));
+ if (!rq->skip_clock_update)
+ rq->clock = sched_clock_cpu(cpu_of(rq));
}
/*
@@ -914,16 +923,12 @@ 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 against
- * ttwu() so that task_cpu() reports a stable number.
- *
- * We need to make an exception for PF_STARTING tasks because the fork
- * path might require task_rq_lock() to work, eg. it can call
- * set_cpus_allowed_ptr() from the cpuset clone_ns code.
+ * 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) && !(p->flags & PF_STARTING));
+ return unlikely(p->state == TASK_WAKING);
}
/*
@@ -936,11 +941,9 @@ static inline struct rq *__task_rq_lock(struct task_struct *p)
struct rq *rq;
for (;;) {
- while (task_is_waking(p))
- cpu_relax();
rq = task_rq(p);
raw_spin_lock(&rq->lock);
- if (likely(rq == task_rq(p) && !task_is_waking(p)))
+ if (likely(rq == task_rq(p)))
return rq;
raw_spin_unlock(&rq->lock);
}
@@ -957,12 +960,10 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
struct rq *rq;
for (;;) {
- while (task_is_waking(p))
- cpu_relax();
local_irq_save(*flags);
rq = task_rq(p);
raw_spin_lock(&rq->lock);
- if (likely(rq == task_rq(p) && !task_is_waking(p)))
+ if (likely(rq == task_rq(p)))
return rq;
raw_spin_unlock_irqrestore(&rq->lock, *flags);
}
@@ -1239,6 +1240,17 @@ void wake_up_idle_cpu(int cpu)
if (!tsk_is_polling(rq->idle))
smp_send_reschedule(cpu);
}
+
+int nohz_ratelimit(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ u64 diff = rq->clock - rq->nohz_stamp;
+
+ rq->nohz_stamp = rq->clock;
+
+ return diff < (NSEC_PER_SEC / HZ) >> 1;
+}
+
#endif /* CONFIG_NO_HZ */
static u64 sched_avg_period(void)
@@ -1781,8 +1793,6 @@ static void double_rq_lock(struct rq *rq1, struct rq *rq2)
raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
}
}
- update_rq_clock(rq1);
- update_rq_clock(rq2);
}
/*
@@ -1813,7 +1823,7 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
}
#endif
-static void calc_load_account_active(struct rq *this_rq);
+static void calc_load_account_idle(struct rq *this_rq);
static void update_sysctl(void);
static int get_update_sysctl_factor(void);
@@ -1870,62 +1880,43 @@ static void set_load_weight(struct task_struct *p)
p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
}
-static void update_avg(u64 *avg, u64 sample)
+static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
{
- s64 diff = sample - *avg;
- *avg += diff >> 3;
-}
-
-static void
-enqueue_task(struct rq *rq, struct task_struct *p, int wakeup, bool head)
-{
- if (wakeup)
- p->se.start_runtime = p->se.sum_exec_runtime;
-
+ update_rq_clock(rq);
sched_info_queued(p);
- p->sched_class->enqueue_task(rq, p, wakeup, head);
+ 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 sleep)
+static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
{
- if (sleep) {
- if (p->se.last_wakeup) {
- update_avg(&p->se.avg_overlap,
- p->se.sum_exec_runtime - p->se.last_wakeup);
- p->se.last_wakeup = 0;
- } else {
- update_avg(&p->se.avg_wakeup,
- sysctl_sched_wakeup_granularity);
- }
- }
-
+ update_rq_clock(rq);
sched_info_dequeued(p);
- p->sched_class->dequeue_task(rq, p, sleep);
+ p->sched_class->dequeue_task(rq, p, flags);
p->se.on_rq = 0;
}
/*
* activate_task - move a task to the runqueue.
*/
-static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
+static void activate_task(struct rq *rq, struct task_struct *p, int flags)
{
if (task_contributes_to_load(p))
rq->nr_uninterruptible--;
- enqueue_task(rq, p, wakeup, false);
+ enqueue_task(rq, p, flags);
inc_nr_running(rq);
}
/*
* deactivate_task - remove a task from the runqueue.
*/
-static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
+static void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
{
if (task_contributes_to_load(p))
rq->nr_uninterruptible++;
- dequeue_task(rq, p, sleep);
+ dequeue_task(rq, p, flags);
dec_nr_running(rq);
}
@@ -2054,21 +2045,18 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
__set_task_cpu(p, new_cpu);
}
-struct migration_req {
- struct list_head list;
-
+struct migration_arg {
struct task_struct *task;
int dest_cpu;
-
- struct completion done;
};
+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 int
-migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
+static bool migrate_task(struct task_struct *p, int dest_cpu)
{
struct rq *rq = task_rq(p);
@@ -2076,15 +2064,7 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
* If the task is not on a runqueue (and not running), then
* the next wake-up will properly place the task.
*/
- if (!p->se.on_rq && !task_running(rq, p))
- return 0;
-
- init_completion(&req->done);
- req->task = p;
- req->dest_cpu = dest_cpu;
- list_add(&req->list, &rq->migration_queue);
-
- return 1;
+ return p->se.on_rq || task_running(rq, p);
}
/*
@@ -2142,7 +2122,7 @@ unsigned long wait_task_inactive(struct task_struct *p, long match_state)
* just go back and repeat.
*/
rq = task_rq_lock(p, &flags);
- trace_sched_wait_task(rq, p);
+ trace_sched_wait_task(p);
running = task_running(rq, p);
on_rq = p->se.on_rq;
ncsw = 0;
@@ -2240,6 +2220,9 @@ void task_oncpu_function_call(struct task_struct *p,
}
#ifdef CONFIG_SMP
+/*
+ * ->cpus_allowed is protected by either TASK_WAKING or rq->lock held.
+ */
static int select_fallback_rq(int cpu, struct task_struct *p)
{
int dest_cpu;
@@ -2256,12 +2239,8 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
return dest_cpu;
/* No more Mr. Nice Guy. */
- if (dest_cpu >= nr_cpu_ids) {
- rcu_read_lock();
- cpuset_cpus_allowed_locked(p, &p->cpus_allowed);
- rcu_read_unlock();
- dest_cpu = cpumask_any_and(cpu_active_mask, &p->cpus_allowed);
-
+ 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
@@ -2278,17 +2257,12 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
}
/*
- * Gets called from 3 sites (exec, fork, wakeup), since it is called without
- * holding rq->lock we need to ensure ->cpus_allowed is stable, this is done
- * by:
- *
- * exec: is unstable, retry loop
- * fork & wake-up: serialize ->cpus_allowed against TASK_WAKING
+ * The caller (fork, wakeup) owns TASK_WAKING, ->cpus_allowed is stable.
*/
static inline
-int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
+int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_flags)
{
- int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
+ int cpu = p->sched_class->select_task_rq(rq, p, sd_flags, wake_flags);
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -2306,6 +2280,12 @@ int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
return cpu;
}
+
+static void update_avg(u64 *avg, u64 sample)
+{
+ s64 diff = sample - *avg;
+ *avg += diff >> 3;
+}
#endif
/***
@@ -2327,16 +2307,13 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
{
int cpu, orig_cpu, this_cpu, success = 0;
unsigned long flags;
+ unsigned long en_flags = ENQUEUE_WAKEUP;
struct rq *rq;
- if (!sched_feat(SYNC_WAKEUPS))
- wake_flags &= ~WF_SYNC;
-
this_cpu = get_cpu();
smp_wmb();
rq = task_rq_lock(p, &flags);
- update_rq_clock(rq);
if (!(p->state & state))
goto out;
@@ -2356,28 +2333,26 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
*
* First fix up the nr_uninterruptible count:
*/
- if (task_contributes_to_load(p))
- rq->nr_uninterruptible--;
+ 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)
+ if (p->sched_class->task_waking) {
p->sched_class->task_waking(rq, p);
+ en_flags |= ENQUEUE_WAKING;
+ }
- __task_rq_unlock(rq);
-
- cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
- if (cpu != orig_cpu) {
- /*
- * Since we migrate the task without holding any rq->lock,
- * we need to be careful with task_rq_lock(), since that
- * might end up locking an invalid rq.
- */
+ 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);
- update_rq_clock(rq);
/*
* We migrated the task without holding either rq->lock, however
@@ -2405,36 +2380,20 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
out_activate:
#endif /* CONFIG_SMP */
- schedstat_inc(p, se.nr_wakeups);
+ schedstat_inc(p, se.statistics.nr_wakeups);
if (wake_flags & WF_SYNC)
- schedstat_inc(p, se.nr_wakeups_sync);
+ schedstat_inc(p, se.statistics.nr_wakeups_sync);
if (orig_cpu != cpu)
- schedstat_inc(p, se.nr_wakeups_migrate);
+ schedstat_inc(p, se.statistics.nr_wakeups_migrate);
if (cpu == this_cpu)
- schedstat_inc(p, se.nr_wakeups_local);
+ schedstat_inc(p, se.statistics.nr_wakeups_local);
else
- schedstat_inc(p, se.nr_wakeups_remote);
- activate_task(rq, p, 1);
+ schedstat_inc(p, se.statistics.nr_wakeups_remote);
+ activate_task(rq, p, en_flags);
success = 1;
- /*
- * Only attribute actual wakeups done by this task.
- */
- if (!in_interrupt()) {
- struct sched_entity *se = &current->se;
- u64 sample = se->sum_exec_runtime;
-
- if (se->last_wakeup)
- sample -= se->last_wakeup;
- else
- sample -= se->start_runtime;
- update_avg(&se->avg_wakeup, sample);
-
- se->last_wakeup = se->sum_exec_runtime;
- }
-
out_running:
- trace_sched_wakeup(rq, p, success);
+ trace_sched_wakeup(p, success);
check_preempt_curr(rq, p, wake_flags);
p->state = TASK_RUNNING;
@@ -2494,42 +2453,9 @@ static void __sched_fork(struct task_struct *p)
p->se.sum_exec_runtime = 0;
p->se.prev_sum_exec_runtime = 0;
p->se.nr_migrations = 0;
- p->se.last_wakeup = 0;
- p->se.avg_overlap = 0;
- p->se.start_runtime = 0;
- p->se.avg_wakeup = sysctl_sched_wakeup_granularity;
#ifdef CONFIG_SCHEDSTATS
- p->se.wait_start = 0;
- p->se.wait_max = 0;
- p->se.wait_count = 0;
- p->se.wait_sum = 0;
-
- p->se.sleep_start = 0;
- p->se.sleep_max = 0;
- p->se.sum_sleep_runtime = 0;
-
- p->se.block_start = 0;
- p->se.block_max = 0;
- p->se.exec_max = 0;
- p->se.slice_max = 0;
-
- p->se.nr_migrations_cold = 0;
- p->se.nr_failed_migrations_affine = 0;
- p->se.nr_failed_migrations_running = 0;
- p->se.nr_failed_migrations_hot = 0;
- p->se.nr_forced_migrations = 0;
-
- p->se.nr_wakeups = 0;
- p->se.nr_wakeups_sync = 0;
- p->se.nr_wakeups_migrate = 0;
- p->se.nr_wakeups_local = 0;
- p->se.nr_wakeups_remote = 0;
- p->se.nr_wakeups_affine = 0;
- p->se.nr_wakeups_affine_attempts = 0;
- p->se.nr_wakeups_passive = 0;
- p->se.nr_wakeups_idle = 0;
-
+ memset(&p->se.statistics, 0, sizeof(p->se.statistics));
#endif
INIT_LIST_HEAD(&p->rt.run_list);
@@ -2550,11 +2476,11 @@ void sched_fork(struct task_struct *p, int clone_flags)
__sched_fork(p);
/*
- * We mark the process as waking here. This guarantees that
+ * We mark the process as running here. This guarantees that
* nobody will actually run it, and a signal or other external
* event cannot wake it up and insert it on the runqueue either.
*/
- p->state = TASK_WAKING;
+ p->state = TASK_RUNNING;
/*
* Revert to default priority/policy on fork if requested.
@@ -2621,31 +2547,27 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
int cpu __maybe_unused = get_cpu();
#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 still have TASK_WAKING but PF_STARTING is gone now, meaning
- * ->cpus_allowed is stable, we have preemption disabled, meaning
- * cpu_online_mask is stable.
+ * We set TASK_WAKING so that select_task_rq() can drop rq->lock
+ * without people poking at ->cpus_allowed.
*/
- cpu = select_task_rq(p, SD_BALANCE_FORK, 0);
+ cpu = select_task_rq(rq, p, SD_BALANCE_FORK, 0);
set_task_cpu(p, cpu);
-#endif
- /*
- * Since the task is not on the rq and we still have TASK_WAKING set
- * nobody else will migrate this task.
- */
- rq = cpu_rq(cpu);
- raw_spin_lock_irqsave(&rq->lock, flags);
-
- BUG_ON(p->state != TASK_WAKING);
p->state = TASK_RUNNING;
- update_rq_clock(rq);
+ task_rq_unlock(rq, &flags);
+#endif
+
+ rq = task_rq_lock(p, &flags);
activate_task(rq, p, 0);
- trace_sched_wakeup_new(rq, p, 1);
+ trace_sched_wakeup_new(p, 1);
check_preempt_curr(rq, p, WF_FORK);
#ifdef CONFIG_SMP
if (p->sched_class->task_woken)
@@ -2865,7 +2787,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
struct mm_struct *mm, *oldmm;
prepare_task_switch(rq, prev, next);
- trace_sched_switch(rq, prev, next);
+ trace_sched_switch(prev, next);
mm = next->mm;
oldmm = prev->active_mm;
/*
@@ -2982,6 +2904,61 @@ static unsigned long calc_load_update;
unsigned long avenrun[3];
EXPORT_SYMBOL(avenrun);
+static long calc_load_fold_active(struct rq *this_rq)
+{
+ long nr_active, delta = 0;
+