[PATCH 4/4] sched: fix wakeup preemption

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

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In my recent wakeup preempt rework I messed up the asym wakeup.
The idea is that it should be easier to preempt lighter tasks
but not harder to preempt heavier tasks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
 kernel/sched_fair.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Index: linux-2.6/kernel/sched_fair.c
===================================================================
--- linux-2.6.orig/kernel/sched_fair.c
+++ linux-2.6/kernel/sched_fair.c
@@ -1243,8 +1243,8 @@ static unsigned long wakeup_gran(struct 
 	 * More easily preempt - nice tasks, while not making it harder for
 	 * + nice tasks.
 	 */
-	if (sched_feat(ASYM_GRAN))
-		gran = calc_delta_mine(gran, NICE_0_LOAD, &se->load);
+	if (sched_feat(ASYM_GRAN) && se->load.weight < NICE_0_LOAD)
+		gran = (gran * se->load.weight) >> NICE_0_SHIFT;
 
 	return gran;
 }
@@ -1296,7 +1296,7 @@ static void check_preempt_wakeup(struct 
 	}
 
 	delta_exec = se->sum_exec_runtime - se->prev_sum_exec_runtime;
-	if (delta_exec > wakeup_gran(pse))
+	if (delta_exec > wakeup_gran(se))
 		resched_task(curr);
 }
 

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