sched: fixup buddy selection

We should set the buddy even though we might already have the
TIF_RESCHED flag set.

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

kernel/sched_fair.c

@@ -1249,15 +1249,15 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
 	if (unlikely(se == pse))
 		return;
 
+	cfs_rq_of(pse)->next = pse;
+
 	/*
 	 * We can come here with TIF_NEED_RESCHED already set from new task
 	 * wake up path.
 	 */
 	if (test_tsk_need_resched(curr))
 		return;
 
-	cfs_rq_of(pse)->next = pse;
-
 	/*
 	 * Batch tasks do not preempt (their preemption is driven by
 	 * the tick):