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Merge branch 'sched/urgent' into sched/core, to pick up fixes before applying new changes

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Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar
2015-12-04 10:27:36 +01:00
parent 525628c73b ecf7d01c22
commit 467386fbbf
4 changed files with 44 additions and 14 deletions
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36
kernel/sched/core.c
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@@ -1957,6 +1957,25 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
goto stat;
#ifdef CONFIG_SMP
/*
* Ensure we load p->on_cpu _after_ p->on_rq, otherwise it would be
* possible to, falsely, observe p->on_cpu == 0.
*
* One must be running (->on_cpu == 1) in order to remove oneself
* from the runqueue.
*
* [S] ->on_cpu = 1; [L] ->on_rq
* UNLOCK rq->lock
* RMB
* LOCK rq->lock
* [S] ->on_rq = 0; [L] ->on_cpu
*
* Pairs with the full barrier implied in the UNLOCK+LOCK on rq->lock
* from the consecutive calls to schedule(); the first switching to our
* task, the second putting it to sleep.
*/
smp_rmb();
/*
* If the owning (remote) cpu is still in the middle of schedule() with
* this task as prev, wait until its done referencing the task.
@@ -1964,7 +1983,13 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
while (p->on_cpu)
cpu_relax();
/*
* Pairs with the smp_wmb() in finish_lock_switch().
* Combined with the control dependency above, we have an effective
* smp_load_acquire() without the need for full barriers.
*
* Pairs with the smp_store_release() in finish_lock_switch().
*
* This ensures that tasks getting woken will be fully ordered against
* their previous state and preserve Program Order.
*/
smp_rmb();
@@ -2050,7 +2075,6 @@ out:
*/
int wake_up_process(struct task_struct *p)
{
WARN_ON(task_is_stopped_or_traced(p));
return try_to_wake_up(p, TASK_NORMAL, 0);
}
EXPORT_SYMBOL(wake_up_process);
@@ -5858,13 +5882,13 @@ static int init_rootdomain(struct root_domain *rd)
{
memset(rd, 0, sizeof(*rd));
if (!alloc_cpumask_var(&rd->span, GFP_KERNEL))
if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))
goto out;
if (!alloc_cpumask_var(&rd->online, GFP_KERNEL))
if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL))
goto free_span;
if (!alloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
if (!zalloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
goto free_online;
if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
goto free_dlo_mask;
init_dl_bw(&rd->dl_bw);