[PATCH 2/2] sched/deadline: fix pull if dl task who's prio changed is not on queue

From: Wanpeng Li <wanpeng.li@linux.intel.com>
To: Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>,
	Kirill Tkhai <ktkhai@parallels.com>,
	linux-kernel@vger.kernel.org,
	Wanpeng Li <wanpeng.li@linux.intel.com>
Subject: [PATCH 2/2] sched/deadline: fix pull if dl task who's prio changed is not on queue
Date: Wed, 19 Nov 2014 16:35:03 +0800	[thread overview]
Message-ID: <1416386103-90800-2-git-send-email-wanpeng.li@linux.intel.com> (raw)
In-Reply-To: <1416386103-90800-1-git-send-email-wanpeng.li@linux.intel.com>

Dl task who is not on queue and it is also the curr task simultaneously 
can not happen. In addition, pull since the priority of a not on queue 
dl task doesn't make any sense.

This patch fix it by don't pull if dl task who's prio changed is not on 
queue.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
---
 kernel/sched/deadline.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index b9e44ae..4eaf55c 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1678,7 +1678,10 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
 static void prio_changed_dl(struct rq *rq, struct task_struct *p,
 			    int oldprio)
 {
-	if (task_on_rq_queued(p) || rq->curr == p) {
+	if (!task_on_rq_queued(p))
+		return;
+
+	if (rq->curr == p) {
 #ifdef CONFIG_SMP
 		/*
 		 * This might be too much, but unfortunately
-- 
1.9.1

