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>

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 09bde2ab2a0a00e2abc9cf6bbb6f8b58448c2f0d..0abfb7ec9e62e2b43ac34fc8aa4404be4cdaa680 100644 (file)
--- 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;
        }