Commit 06c3bc65 authored Feb 02, 2011 by Peter Zijlstra Committed by Ingo Molnar Feb 03, 2011

sched: Fix update_curr_rt()



cpu_stopper_thread()
  migration_cpu_stop()
    __migrate_task()
      deactivate_task()
        dequeue_task()
          dequeue_task_rq()
            update_curr_rt()

Will call update_curr_rt() on rq->curr, which at that time is
rq->stop. The problem is that rq->stop.prio matches an RT prio and
thus falsely assumes its a rt_sched_class task.

Reported-Debuged-Tested-Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Cc: stable@kernel.org # .37
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 1e1dbb25

kernel/sched_rt.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -625,7 +625,7 @@ static void update_curr_rt(struct rq *rq)
		struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
		u64 delta_exec;

		if (!task_has_rt_policy(curr))
		if (curr->sched_class != &rt_sched_class)
		return;

		delta_exec = rq->clock_task - curr->se.exec_start;