[tip:sched/core] sched: Fix the task-group check in tg_has_rt_tasks()

[tip-bot for Oleg Nesterov <tipbot@zytor.com>]

Commit-ID:  8651c65844e93af44554272b7e0d2b142837b244
Gitweb:     http://git.kernel.org/tip/8651c65844e93af44554272b7e0d2b142837b244
Author:     Oleg Nesterov <oleg@redhat.com>
AuthorDate: Sun, 21 Sep 2014 21:33:36 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Wed, 24 Sep 2014 14:47:00 +0200

sched: Fix the task-group check in tg_has_rt_tasks()

tg_has_rt_tasks() wants to find an RT task in this task_group, but
task_rq(p)->rt.tg wrongly checks the root rt_rq.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Link: http://lkml.kernel.org/r/20140921193336.GA28618@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 09bde2a..0abfb7e 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7441,7 +7441,7 @@ static inline int tg_has_rt_tasks(struct task_group *tg)
 	struct task_struct *g, *p;
 
 	for_each_process_thread(g, p) {
-		if (rt_task(p) && task_rq(p)->rt.tg == tg)
+		if (rt_task(p) && task_group(p) == tg)
 			return 1;
 	}