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>

1 files changed, 11 insertions, 17 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;
 }