diff options
| author | Darren Hart <dvhart@linux.intel.com> | 2011-02-22 13:04:33 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-03-04 11:14:29 +0100 |
| commit | a2f5c9ab79f78e8b91ac993e0543d65b661dd19b (patch) | |
| tree | 9fcdae7cad6745d02d5389ab591b454bb4c17b60 /kernel/sched_fair.c | |
| parent | e0a92c17470775cd85bac52f5372ccc3dc58254a (diff) | |
sched: Allow SCHED_BATCH to preempt SCHED_IDLE tasks
Perform the test for SCHED_IDLE before testing for SCHED_BATCH (and
ensure idle tasks don't preempt idle tasks) so the non-interactive,
but still important, SCHED_BATCH tasks will run in favor of the very
low priority SCHED_IDLE tasks.
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
LKML-Reference: <1298408674-3130-2-git-send-email-dvhart@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
| -rw-r--r-- | kernel/sched_fair.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 3a88dee165c..1438e13cf8b 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1870,16 +1870,18 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ if (test_tsk_need_resched(curr)) return; + /* Idle tasks are by definition preempted by non-idle tasks. */ + if (unlikely(curr->policy == SCHED_IDLE) && + likely(p->policy != SCHED_IDLE)) + goto preempt; + /* - * Batch and idle tasks do not preempt (their preemption is driven by - * the tick): + * Batch and idle tasks do not preempt non-idle tasks (their preemption + * is driven by the tick): */ if (unlikely(p->policy != SCHED_NORMAL)) return; - /* Idle tasks are by definition preempted by everybody. */ - if (unlikely(curr->policy == SCHED_IDLE)) - goto preempt; if (!sched_feat(WAKEUP_PREEMPT)) return; |