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| author | Mike Galbraith <efault@gmx.de> | 2010-03-11 17:17:04 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-03-11 18:32:53 +0100 |
| commit | 13814d42e45dfbe845a0bbe5184565d9236896ae (patch) | |
| tree | 6c4c010829e126af2c4a0620e47ee00d867d7f5d | |
| parent | c6ee36c423c3ed1fb86bb3eabba9fc256a300d16 (diff) | |
| download | op-kernel-dev-13814d42e45dfbe845a0bbe5184565d9236896ae.zip op-kernel-dev-13814d42e45dfbe845a0bbe5184565d9236896ae.tar.gz | |
sched: Remove ASYM_GRAN feature
This features has been enabled for quite a while, after testing showed that
easing preemption for light tasks was harmful to high priority threads.
Remove the feature flag.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301675.6785.44.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/sched_fair.c | 28 | ||||
| -rw-r--r-- | kernel/sched_features.h | 6 |
2 files changed, 11 insertions, 23 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 1d99535..9357ecd 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1583,24 +1583,18 @@ wakeup_gran(struct sched_entity *curr, struct sched_entity *se) /* * Since its curr running now, convert the gran from real-time * to virtual-time in his units. + * + * By using 'se' instead of 'curr' we penalize light tasks, so + * they get preempted easier. That is, if 'se' < 'curr' then + * the resulting gran will be larger, therefore penalizing the + * lighter, if otoh 'se' > 'curr' then the resulting gran will + * be smaller, again penalizing the lighter task. + * + * This is especially important for buddies when the leftmost + * task is higher priority than the buddy. */ - if (sched_feat(ASYM_GRAN)) { - /* - * By using 'se' instead of 'curr' we penalize light tasks, so - * they get preempted easier. That is, if 'se' < 'curr' then - * the resulting gran will be larger, therefore penalizing the - * lighter, if otoh 'se' > 'curr' then the resulting gran will - * be smaller, again penalizing the lighter task. - * - * This is especially important for buddies when the leftmost - * task is higher priority than the buddy. - */ - if (unlikely(se->load.weight != NICE_0_LOAD)) - gran = calc_delta_fair(gran, se); - } else { - if (unlikely(curr->load.weight != NICE_0_LOAD)) - gran = calc_delta_fair(gran, curr); - } + if (unlikely(se->load.weight != NICE_0_LOAD)) + gran = calc_delta_fair(gran, se); return gran; } diff --git a/kernel/sched_features.h b/kernel/sched_features.h index f54b6f9..83c66e8 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -17,12 +17,6 @@ SCHED_FEAT(START_DEBIT, 1) SCHED_FEAT(WAKEUP_PREEMPT, 1) /* - * When converting the wakeup granularity to virtual time, do it such - * that heavier tasks preempting a lighter task have an edge. - */ -SCHED_FEAT(ASYM_GRAN, 1) - -/* * Based on load and program behaviour, see if it makes sense to place * a newly woken task on the same cpu as the task that woke it -- * improve cache locality. Typically used with SYNC wakeups as |
