aboutsummaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorMike Galbraith <efault@gmx.de>2009-11-12 11:07:44 +0100
committerIngo Molnar <mingo@elte.hu>2009-11-12 12:28:29 +0100
commit055a00865dcfc8e61f3cbefbb879c9577bd36ae5 (patch)
tree73d406a3e05b5226c8a83f9ce3f6d0c67a063cb7 /kernel
parentaa021baa3295fa6e3f367d80f8955dd5176656eb (diff)
downloadkernel_samsung_espresso10-055a00865dcfc8e61f3cbefbb879c9577bd36ae5.zip
kernel_samsung_espresso10-055a00865dcfc8e61f3cbefbb879c9577bd36ae5.tar.gz
kernel_samsung_espresso10-055a00865dcfc8e61f3cbefbb879c9577bd36ae5.tar.bz2
sched: Fix/add missing update_rq_clock() calls
kthread_bind(), migrate_task() and sched_fork were missing updates, and try_to_wake_up() was updating after having already used the stale clock. Aside from preventing potential latency hits, there' a side benefit in that early boot printk time stamps become monotonic. Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258020464.6491.2.camel@marge.simson.net> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <new-submission>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched.c17
1 files changed, 12 insertions, 5 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 3c11ae0..701eca4 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2017,6 +2017,7 @@ void kthread_bind(struct task_struct *p, unsigned int cpu)
}
spin_lock_irqsave(&rq->lock, flags);
+ update_rq_clock(rq);
set_task_cpu(p, cpu);
p->cpus_allowed = cpumask_of_cpu(cpu);
p->rt.nr_cpus_allowed = 1;
@@ -2115,6 +2116,7 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req)
* it is sufficient to simply update the task's cpu field.
*/
if (!p->se.on_rq && !task_running(rq, p)) {
+ update_rq_clock(rq);
set_task_cpu(p, dest_cpu);
return 0;
}
@@ -2376,14 +2378,15 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
task_rq_unlock(rq, &flags);
cpu = p->sched_class->select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
- if (cpu != orig_cpu)
+ if (cpu != orig_cpu) {
+ local_irq_save(flags);
+ rq = cpu_rq(cpu);
+ update_rq_clock(rq);
set_task_cpu(p, cpu);
-
+ local_irq_restore(flags);
+ }
rq = task_rq_lock(p, &flags);
- if (rq != orig_rq)
- update_rq_clock(rq);
-
WARN_ON(p->state != TASK_WAKING);
cpu = task_cpu(p);
@@ -2545,6 +2548,7 @@ static void __sched_fork(struct task_struct *p)
void sched_fork(struct task_struct *p, int clone_flags)
{
int cpu = get_cpu();
+ unsigned long flags;
__sched_fork(p);
@@ -2581,7 +2585,10 @@ void sched_fork(struct task_struct *p, int clone_flags)
#ifdef CONFIG_SMP
cpu = p->sched_class->select_task_rq(p, SD_BALANCE_FORK, 0);
#endif
+ local_irq_save(flags);
+ update_rq_clock(cpu_rq(cpu));
set_task_cpu(p, cpu);
+ local_irq_restore(flags);
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
if (likely(sched_info_on()))