sched: Clean up idle task SMP logic

commit 6c3b4d44ba2838f00614a5a2d777d4401e0bfd71 upstream.

The idle post_schedule flag is just a vile waste of time, furthermore
it appears unneeded, move the idle_enter_fair() call into
pick_next_task_idle().

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: alex.shi@linaro.org
Cc: mingo@kernel.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-aljykihtxJt3mkokxi0qZurb@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c
index d8da01008d390a770acb43c22bfb1de38e389a76..ecc371e86da195d1948c65464d429a6a51bee2c5 100644 (file)
--- a/kernel/sched/idle_task.c
+++ b/kernel/sched/idle_task.c
@@ -19,11 +19,6 @@ static void pre_schedule_idle(struct rq *rq, struct task_struct *prev)
        idle_exit_fair(rq);
        rq_last_tick_reset(rq);
 }
-
-static void post_schedule_idle(struct rq *rq)
-{
-       idle_enter_fair(rq);
-}
 #endif /* CONFIG_SMP */
 /*
  * Idle tasks are unconditionally rescheduled:
@@ -37,8 +32,7 @@ static struct task_struct *pick_next_task_idle(struct rq *rq)
 {
        schedstat_inc(rq, sched_goidle);
 #ifdef CONFIG_SMP
-       /* Trigger the post schedule to do an idle_enter for CFS */
-       rq->post_schedule = 1;
+       idle_enter_fair(rq);
 #endif
        return rq->idle;
 }
@@ -102,7 +96,6 @@ const struct sched_class idle_sched_class = {
 #ifdef CONFIG_SMP
        .select_task_rq         = select_task_rq_idle,
        .pre_schedule           = pre_schedule_idle,
-       .post_schedule          = post_schedule_idle,
 #endif
 
        .set_curr_task          = set_curr_task_idle,