From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Tue, 4 Nov 2008 20:25:08 +0000 (+0100)
Subject: sched: fix fair preempt check
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d95f98d0691d3aba5e35850011946a08c9b36428;p=linux-beck.git

sched: fix fair preempt check

Impact: fix cross-class preemption

Inter-class wakeup preemptions should go on class order.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 6167336a2372..ebd6de8d17fd 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1329,6 +1329,9 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
 		return;
 	}
 
+	if (unlikely(p->sched_class != &fair_sched_class))
+		return;
+
 	if (unlikely(se == pse))
 		return;