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authorGregory Haskins <ghaskins@novell.com>2008-06-27 14:30:00 -0600
committerIngo Molnar <mingo@elte.hu>2008-07-04 12:50:22 +0200
commit2087a1ad822cd3a68b73338457047fcc54da726b (patch)
tree1ebc45b2499034ffe37b29bf7a748b8e992cd870 /kernel/sched_fair.c
parentc4acb2c0669c5c5c9b28e9d02a34b5c67edf7092 (diff)
sched: add avg-overlap support to RT tasks
We have the notion of tracking process-coupling (a.k.a. buddy-wake) via the p->se.last_wake / p->se.avg_overlap facilities, but it is only used for cfs to cfs interactions. There is no reason why an rt to cfs interaction cannot share in establishing a relationhip in a similar manner. Because PREEMPT_RT runs many kernel threads as FIFO priority, we often times have heavy interaction between RT threads waking CFS applications. This patch offers a substantial boost (50-60%+) in perfomance under those circumstances. Signed-off-by: Gregory Haskins <ghaskins@novell.com> Cc: npiggin@suse.de Cc: rostedt@goodmis.org Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r--kernel/sched_fair.c21
1 files changed, 2 insertions, 19 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 2e43d4a748c..f2aa987027d 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -726,21 +726,6 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
__enqueue_entity(cfs_rq, se);
}
-static void update_avg(u64 *avg, u64 sample)
-{
- s64 diff = sample - *avg;
- *avg += diff >> 3;
-}
-
-static void update_avg_stats(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- if (!se->last_wakeup)
- return;
-
- update_avg(&se->avg_overlap, se->sum_exec_runtime - se->last_wakeup);
- se->last_wakeup = 0;
-}
-
static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
{
@@ -751,7 +736,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
update_stats_dequeue(cfs_rq, se);
if (sleep) {
- update_avg_stats(cfs_rq, se);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
struct task_struct *tsk = task_of(se);
@@ -1196,9 +1180,9 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
* a reasonable amount of time then attract this newly
* woken task:
*/
- if (sync && balanced && curr->sched_class == &fair_sched_class) {
+ if (sync && balanced) {
if (curr->se.avg_overlap < sysctl_sched_migration_cost &&
- p->se.avg_overlap < sysctl_sched_migration_cost)
+ p->se.avg_overlap < sysctl_sched_migration_cost)
return 1;
}
@@ -1359,7 +1343,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
return;
}
- se->last_wakeup = se->sum_exec_runtime;
if (unlikely(se == pse))
return;