sched: old sleeper bonus

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

kernel/sched.c

@@ -680,6 +680,7 @@ enum {
 	SCHED_FEAT_SYNC_WAKEUPS		= 32,
 	SCHED_FEAT_HRTICK		= 64,
 	SCHED_FEAT_DOUBLE_TICK		= 128,
+	SCHED_FEAT_NORMALIZED_SLEEPER	= 256,
 };
 
 const_debug unsigned int sysctl_sched_features =
@@ -690,7 +691,8 @@ const_debug unsigned int sysctl_sched_features =
 		SCHED_FEAT_CACHE_HOT_BUDDY	* 1 |
 		SCHED_FEAT_SYNC_WAKEUPS		* 1 |
 		SCHED_FEAT_HRTICK		* 1 |
-		SCHED_FEAT_DOUBLE_TICK		* 0;
+		SCHED_FEAT_DOUBLE_TICK		* 0 |
+		SCHED_FEAT_NORMALIZED_SLEEPER	* 1;
 
 #define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x)
 

kernel/sched_fair.c

@@ -501,8 +501,11 @@ 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 -= calc_delta_fair(sysctl_sched_latency,
-						    &cfs_rq->load);
+			if (sched_feat(NORMALIZED_SLEEPER))
+				vruntime -= calc_delta_fair(sysctl_sched_latency,
+						&cfs_rq->load);
+			else
+				vruntime -= sysctl_sched_latency;
 		}
 
 		/* ensure we never gain time by being placed backwards. */