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

Pull scheduler fixes from Ingo Molnar:
 "Two fixes:

   - a SCHED_DEADLINE task selection fix
   - a sched/numa related lockdep splat fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Check for stop task appearance when balancing happens
  sched/numa: Fix task_numa_free() lockdep splat
This commit is contained in:
Linus Torvalds 2014-04-19 10:40:51 -07:00
commit 8f98f6f5d6
4 changed files with 32 additions and 11 deletions

View file

@ -1021,8 +1021,17 @@ struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
dl_rq = &rq->dl;
if (need_pull_dl_task(rq, prev))
if (need_pull_dl_task(rq, prev)) {
pull_dl_task(rq);
/*
* pull_rt_task() can drop (and re-acquire) rq->lock; this
* means a stop task can slip in, in which case we need to
* re-start task selection.
*/
if (rq->stop && rq->stop->on_rq)
return RETRY_TASK;
}
/*
* When prev is DL, we may throttle it in put_prev_task().
* So, we update time before we check for dl_nr_running.

View file

@ -1497,7 +1497,7 @@ static void task_numa_placement(struct task_struct *p)
/* If the task is part of a group prevent parallel updates to group stats */
if (p->numa_group) {
group_lock = &p->numa_group->lock;
spin_lock(group_lock);
spin_lock_irq(group_lock);
}
/* Find the node with the highest number of faults */
@ -1572,7 +1572,7 @@ static void task_numa_placement(struct task_struct *p)
}
}
spin_unlock(group_lock);
spin_unlock_irq(group_lock);
}
/* Preferred node as the node with the most faults */
@ -1677,7 +1677,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
if (!join)
return;
double_lock(&my_grp->lock, &grp->lock);
BUG_ON(irqs_disabled());
double_lock_irq(&my_grp->lock, &grp->lock);
for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++) {
my_grp->faults[i] -= p->numa_faults_memory[i];
@ -1691,7 +1692,7 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
grp->nr_tasks++;
spin_unlock(&my_grp->lock);
spin_unlock(&grp->lock);
spin_unlock_irq(&grp->lock);
rcu_assign_pointer(p->numa_group, grp);
@ -1710,14 +1711,14 @@ void task_numa_free(struct task_struct *p)
void *numa_faults = p->numa_faults_memory;
if (grp) {
spin_lock(&grp->lock);
spin_lock_irq(&grp->lock);
for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
grp->faults[i] -= p->numa_faults_memory[i];
grp->total_faults -= p->total_numa_faults;
list_del(&p->numa_entry);
grp->nr_tasks--;
spin_unlock(&grp->lock);
spin_unlock_irq(&grp->lock);
rcu_assign_pointer(p->numa_group, NULL);
put_numa_group(grp);
}
@ -6727,7 +6728,8 @@ static int idle_balance(struct rq *this_rq)
out:
/* Is there a task of a high priority class? */
if (this_rq->nr_running != this_rq->cfs.h_nr_running &&
(this_rq->dl.dl_nr_running ||
((this_rq->stop && this_rq->stop->on_rq) ||
this_rq->dl.dl_nr_running ||
(this_rq->rt.rt_nr_running && !rt_rq_throttled(&this_rq->rt))))
pulled_task = -1;

View file

@ -1362,10 +1362,11 @@ pick_next_task_rt(struct rq *rq, struct task_struct *prev)
pull_rt_task(rq);
/*
* pull_rt_task() can drop (and re-acquire) rq->lock; this
* means a dl task can slip in, in which case we need to
* re-start task selection.
* means a dl or stop task can slip in, in which case we need
* to re-start task selection.
*/
if (unlikely(rq->dl.dl_nr_running))
if (unlikely((rq->stop && rq->stop->on_rq) ||
rq->dl.dl_nr_running))
return RETRY_TASK;
}

View file

@ -1385,6 +1385,15 @@ static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
}
static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
{
if (l1 > l2)
swap(l1, l2);
spin_lock_irq(l1);
spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
}
static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
{
if (l1 > l2)