Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  cpuset: Fix cpuset_cpus_allowed_fallback(), don't update tsk->rt.nr_cpus_allowed
  sched: Fix ->min_vruntime calculation in dequeue_entity()
  sched: Fix ttwu() for __ARCH_WANT_INTERRUPTS_ON_CTXSW
  sched: More sched_domain iterations fixes
This commit is contained in:
Linus Torvalds 2011-05-28 12:56:46 -07:00
commit 08a8b79600
8 changed files with 65 additions and 27 deletions

View File

@ -146,7 +146,7 @@ static inline void cpuset_cpus_allowed(struct task_struct *p,
static inline int cpuset_cpus_allowed_fallback(struct task_struct *p)
{
cpumask_copy(&p->cpus_allowed, cpu_possible_mask);
do_set_cpus_allowed(p, cpu_possible_mask);
return cpumask_any(cpu_active_mask);
}

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@ -1841,9 +1841,16 @@ static inline void rcu_copy_process(struct task_struct *p)
#endif
#ifdef CONFIG_SMP
extern void do_set_cpus_allowed(struct task_struct *p,
const struct cpumask *new_mask);
extern int set_cpus_allowed_ptr(struct task_struct *p,
const struct cpumask *new_mask);
#else
static inline void do_set_cpus_allowed(struct task_struct *p,
const struct cpumask *new_mask)
{
}
static inline int set_cpus_allowed_ptr(struct task_struct *p,
const struct cpumask *new_mask)
{

View File

@ -2190,7 +2190,7 @@ int cpuset_cpus_allowed_fallback(struct task_struct *tsk)
rcu_read_lock();
cs = task_cs(tsk);
if (cs)
cpumask_copy(&tsk->cpus_allowed, cs->cpus_allowed);
do_set_cpus_allowed(tsk, cs->cpus_allowed);
rcu_read_unlock();
/*
@ -2217,7 +2217,7 @@ int cpuset_cpus_allowed_fallback(struct task_struct *tsk)
* 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);
do_set_cpus_allowed(tsk, cpu_possible_mask);
cpu = cpumask_any(cpu_active_mask);
}

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@ -202,8 +202,8 @@ void kthread_bind(struct task_struct *p, unsigned int cpu)
return;
}
p->cpus_allowed = cpumask_of_cpu(cpu);
p->rt.nr_cpus_allowed = 1;
/* It's safe because the task is inactive. */
do_set_cpus_allowed(p, cpumask_of(cpu));
p->flags |= PF_THREAD_BOUND;
}
EXPORT_SYMBOL(kthread_bind);

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@ -2573,7 +2573,26 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
if (!next)
smp_send_reschedule(cpu);
}
#endif
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
static int ttwu_activate_remote(struct task_struct *p, int wake_flags)
{
struct rq *rq;
int ret = 0;
rq = __task_rq_lock(p);
if (p->on_cpu) {
ttwu_activate(rq, p, ENQUEUE_WAKEUP);
ttwu_do_wakeup(rq, p, wake_flags);
ret = 1;
}
__task_rq_unlock(rq);
return ret;
}
#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
#endif /* CONFIG_SMP */
static void ttwu_queue(struct task_struct *p, int cpu)
{
@ -2631,17 +2650,17 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
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.
* In case the architecture enables interrupts in
* context_switch(), we cannot busy wait, since that
* would lead to deadlocks when an interrupt hits and
* tries to wake up @prev. So bail and do a complete
* remote wakeup.
*/
if (p == current) {
ttwu_queue(p, cpu);
if (ttwu_activate_remote(p, wake_flags))
goto stat;
}
#endif
#else
cpu_relax();
#endif
}
/*
* Pairs with the smp_wmb() in finish_lock_switch().
@ -5841,7 +5860,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
idle->state = TASK_RUNNING;
idle->se.exec_start = sched_clock();
cpumask_copy(&idle->cpus_allowed, cpumask_of(cpu));
do_set_cpus_allowed(idle, cpumask_of(cpu));
/*
* We're having a chicken and egg problem, even though we are
* holding rq->lock, the cpu isn't yet set to this cpu so the
@ -5929,6 +5948,16 @@ static inline void sched_init_granularity(void)
}
#ifdef CONFIG_SMP
void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
{
if (p->sched_class && p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, new_mask);
else {
cpumask_copy(&p->cpus_allowed, new_mask);
p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
}
}
/*
* This is how migration works:
*
@ -5974,12 +6003,7 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
goto out;
}
if (p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, new_mask);
else {
cpumask_copy(&p->cpus_allowed, new_mask);
p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
}
do_set_cpus_allowed(p, new_mask);
/* Can the task run on the task's current CPU? If so, we're done */
if (cpumask_test_cpu(task_cpu(p), new_mask))

View File

@ -1076,8 +1076,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
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
@ -1086,6 +1084,9 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
*/
if (!(flags & DEQUEUE_SLEEP))
se->vruntime -= cfs_rq->min_vruntime;
update_min_vruntime(cfs_rq);
update_cfs_shares(cfs_rq);
}
/*

View File

@ -1263,6 +1263,7 @@ static int find_lowest_rq(struct task_struct *task)
if (!cpumask_test_cpu(this_cpu, lowest_mask))
this_cpu = -1; /* Skip this_cpu opt if not among lowest */
rcu_read_lock();
for_each_domain(cpu, sd) {
if (sd->flags & SD_WAKE_AFFINE) {
int best_cpu;
@ -1272,15 +1273,20 @@ static int find_lowest_rq(struct task_struct *task)
* remote processor.
*/
if (this_cpu != -1 &&
cpumask_test_cpu(this_cpu, sched_domain_span(sd)))
cpumask_test_cpu(this_cpu, sched_domain_span(sd))) {
rcu_read_unlock();
return this_cpu;
}
best_cpu = cpumask_first_and(lowest_mask,
sched_domain_span(sd));
if (best_cpu < nr_cpu_ids)
if (best_cpu < nr_cpu_ids) {
rcu_read_unlock();
return best_cpu;
}
}
}
rcu_read_unlock();
/*
* And finally, if there were no matches within the domains

View File

@ -37,7 +37,7 @@ static int show_schedstat(struct seq_file *seq, void *v)
#ifdef CONFIG_SMP
/* domain-specific stats */
preempt_disable();
rcu_read_lock();
for_each_domain(cpu, sd) {
enum cpu_idle_type itype;
@ -64,7 +64,7 @@ static int show_schedstat(struct seq_file *seq, void *v)
sd->ttwu_wake_remote, sd->ttwu_move_affine,
sd->ttwu_move_balance);
}
preempt_enable();
rcu_read_unlock();
#endif
}
kfree(mask_str);