diff options
author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-11-28 18:51:02 +0100 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-12-09 10:03:07 +0100 |
commit | 3a7e73a2e26fffdbc46ba95fc0425418984f5140 (patch) | |
tree | 02fdd1c081acfde7522a971bc2969bca76ca90c7 /kernel/sched_fair.c | |
parent | a65ac745e47e91f9d98dbf07f22ed0492e34d998 (diff) | |
download | linux-3a7e73a2e26fffdbc46ba95fc0425418984f5140.tar.bz2 |
sched: Clean up check_preempt_wakeup()
Streamline the wakeup preemption code a bit, unifying the preempt path
so that they all do the same.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r-- | kernel/sched_fair.c | 73 |
1 files changed, 33 insertions, 40 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 4dec18579c9a..76b5792c4198 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1651,10 +1651,8 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ int sync = wake_flags & WF_SYNC; int scale = cfs_rq->nr_running >= sched_nr_latency; - if (unlikely(rt_prio(p->prio))) { - resched_task(curr); - return; - } + if (unlikely(rt_prio(p->prio))) + goto preempt; if (unlikely(p->sched_class != &fair_sched_class)) return; @@ -1680,52 +1678,47 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ return; /* Idle tasks are by definition preempted by everybody. */ - if (unlikely(curr->policy == SCHED_IDLE)) { - resched_task(curr); - return; - } + if (unlikely(curr->policy == SCHED_IDLE)) + goto preempt; - if ((sched_feat(WAKEUP_SYNC) && sync) || - (sched_feat(WAKEUP_OVERLAP) && - (se->avg_overlap < sysctl_sched_migration_cost && - pse->avg_overlap < sysctl_sched_migration_cost))) { - resched_task(curr); - return; - } + if (sched_feat(WAKEUP_SYNC) && sync) + goto preempt; - if (sched_feat(WAKEUP_RUNNING)) { - if (pse->avg_running < se->avg_running) { - set_next_buddy(pse); - resched_task(curr); - return; - } - } + if (sched_feat(WAKEUP_OVERLAP) && + se->avg_overlap < sysctl_sched_migration_cost && + pse->avg_overlap < sysctl_sched_migration_cost) + goto preempt; + + if (sched_feat(WAKEUP_RUNNING) && pse->avg_running < se->avg_running) + goto preempt; if (!sched_feat(WAKEUP_PREEMPT)) return; + update_curr(cfs_rq); find_matching_se(&se, &pse); - BUG_ON(!pse); + if (wakeup_preempt_entity(se, pse) == 1) + goto preempt; - update_curr(cfs_rq); + return; - if (wakeup_preempt_entity(se, pse) == 1) { - resched_task(curr); - /* - * Only set the backward buddy when the current task is still - * on the rq. This can happen when a wakeup gets interleaved - * with schedule on the ->pre_schedule() or idle_balance() - * point, either of which can * drop the rq lock. - * - * Also, during early boot the idle thread is in the fair class, - * for obvious reasons its a bad idea to schedule back to it. - */ - if (unlikely(!se->on_rq || curr == rq->idle)) - return; - if (sched_feat(LAST_BUDDY) && scale && entity_is_task(se)) - set_last_buddy(se); - } +preempt: + resched_task(curr); + /* + * Only set the backward buddy when the current task is still + * on the rq. This can happen when a wakeup gets interleaved + * with schedule on the ->pre_schedule() or idle_balance() + * point, either of which can * drop the rq lock. + * + * Also, during early boot the idle thread is in the fair class, + * for obvious reasons its a bad idea to schedule back to it. + */ + if (unlikely(!se->on_rq || curr == rq->idle)) + return; + + if (sched_feat(LAST_BUDDY) && scale && entity_is_task(se)) + set_last_buddy(se); } static struct task_struct *pick_next_task_fair(struct rq *rq) |