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)
update_rq_clock(rq);
sched_info_dequeued(p);
p->sched_class->dequeue_task(rq, p, flags);
- p->se.on_rq = 0;
}
/*
* 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->se.on_rq && test_tsk_need_resched(rq->curr))
+ if (rq->curr->on_rq && test_tsk_need_resched(rq->curr))
rq->skip_clock_update = 1;
}
* 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, struct rq *rq)
+static bool need_migrate_task(struct task_struct *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);
+ bool running = p->on_rq || p->on_cpu;
+ smp_rmb(); /* finish_lock_switch() */
+ return running;
}
/*
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 */
#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)
{
}
/*
- * 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
}
#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 rq *rq, struct task_struct *p, int cpu, int wake_flags)
{
+#ifdef CONFIG_SCHEDSTATS
+#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);
+ for_each_domain(this_cpu, sd) {
+ if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
+ schedstat_inc(sd, ttwu_wake_remote);
+ break;
+ }
+ }
+ }
+#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)
+static void
+ttwu_post_activation(struct task_struct *p, struct rq *rq, int wake_flags)
{
- trace_sched_wakeup(p, success);
+ trace_sched_wakeup(p, true);
check_preempt_curr(rq, p, wake_flags);
p->state = TASK_RUNNING;
this_cpu = get_cpu();
smp_wmb();
- rq = task_rq_lock(p, &flags);
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
+ rq = __task_rq_lock(p);
if (!(p->state & state))
goto out;
- if (p->se.on_rq)
+ cpu = task_cpu(p);
+
+ if (p->on_rq)
goto out_running;
- cpu = task_cpu(p);
orig_cpu = cpu;
-
#ifdef CONFIG_SMP
if (unlikely(task_running(rq, p)))
goto out_activate;
p->state = TASK_WAKING;
if (p->sched_class->task_waking) {
- p->sched_class->task_waking(rq, p);
+ p->sched_class->task_waking(p);
en_flags |= ENQUEUE_WAKING;
}
- cpu = select_task_rq(rq, p, SD_BALANCE_WAKE, wake_flags);
+ cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
if (cpu != orig_cpu)
set_task_cpu(p, cpu);
__task_rq_unlock(rq);
WARN_ON(task_cpu(p) != cpu);
WARN_ON(p->state != TASK_WAKING);
-#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 */
-
out_activate:
#endif /* CONFIG_SMP */
- ttwu_activate(p, rq, wake_flags & WF_SYNC, orig_cpu != cpu,
- cpu == this_cpu, en_flags);
- success = 1;
+ ttwu_activate(rq, p, en_flags);
out_running:
- ttwu_post_activation(p, rq, wake_flags, success);
+ ttwu_post_activation(p, rq, wake_flags);
+ ttwu_stat(rq, p, cpu, wake_flags);
+ success = 1;
out:
- task_rq_unlock(rq, &flags);
+ __task_rq_unlock(rq);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
put_cpu();
return success;
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);
if (!(p->state & TASK_NORMAL))
return;
- 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_post_activation(p, rq, 0);
+ ttwu_stat(rq, p, smp_processor_id(), 0);
}
/**
*/
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);
* 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);
+ cpu = select_task_rq(p, SD_BALANCE_FORK, 0);
set_task_cpu(p, cpu);
p->state = TASK_RUNNING;
rq = task_rq_lock(p, &flags);
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)
int dest_cpu;
rq = task_rq_lock(p, &flags);
- dest_cpu = p->sched_class->select_task_rq(rq, p, SD_BALANCE_EXEC, 0);
+ 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, rq)) {
+ likely(cpu_active(dest_cpu)) && need_migrate_task(p)) {
struct migration_arg arg = { p, dest_cpu };
task_rq_unlock(rq, &flags);
static void put_prev_task(struct rq *rq, struct task_struct *prev)
{
- if (prev->se.on_rq)
+ if (prev->on_rq)
update_rq_clock(rq);
prev->sched_class->put_prev_task(rq, prev);
}
if (to_wakeup)
try_to_wake_up_local(to_wakeup);
}
+
deactivate_task(rq, prev, DEQUEUE_SLEEP);
+ prev->on_rq = 0;
/*
* If we are going to sleep and we have plugged IO queued, make
BUG_ON(prio < 0 || prio > MAX_PRIO);
+ lockdep_assert_held(&p->pi_lock);
+
rq = task_rq_lock(p, &flags);
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);
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);
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);
raw_spin_unlock_irqrestore(&p->pi_lock, 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);
{
struct task_struct *p;
unsigned long flags;
- struct rq *rq;
int retval;
get_online_cpus();
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();
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;
- }
+ raw_spin_lock_irqsave(&p->pi_lock, flags);
+ rq = __task_rq_lock(p);
if (!cpumask_intersects(new_mask, cpu_active_mask)) {
ret = -EINVAL;
goto out;
dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
- if (migrate_task(p, rq)) {
+ if (need_migrate_task(p)) {
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);
+ raw_spin_unlock_irqrestore(&p->pi_lock, 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);
+ raw_spin_unlock_irqrestore(&p->pi_lock, flags);
return ret;
}
* 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);
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);
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);