sched: fix fair sleepers
Ingo Molnar [Fri, 14 Mar 2008 21:16:08 +0000 (22:16 +0100)]
Fair sleepers need to scale their latency target down by runqueue
weight. Otherwise busy systems will gain ever larger sleep bonus.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

kernel/sched_fair.c

index 31c4a29..31aa1b9 100644 (file)
@@ -528,8 +528,10 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 
        if (!initial) {
                /* sleeps upto a single latency don't count. */
-               if (sched_feat(NEW_FAIR_SLEEPERS))
-                       vruntime -= sysctl_sched_latency;
+               if (sched_feat(NEW_FAIR_SLEEPERS)) {
+                       vruntime -= calc_delta_fair(sysctl_sched_latency,
+                                                   &cfs_rq->load);
+               }
 
                /* ensure we never gain time by being placed backwards. */
                vruntime = max_vruntime(se->vruntime, vruntime);