[tip:timers/nohz] nohz: Include local CPU in full dynticks global kick

From: tip-bot for Frederic Weisbecker
Date: Fri Aug 16 2013 - 14:49:21 EST


Commit-ID: c2e7fcf53c3cb02b4ada1c66a9bc8a4d97d58aba
Gitweb: http://git.kernel.org/tip/c2e7fcf53c3cb02b4ada1c66a9bc8a4d97d58aba
Author: Frederic Weisbecker <fweisbec@xxxxxxxxx>
AuthorDate: Fri, 2 Aug 2013 18:29:56 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Fri, 16 Aug 2013 17:55:33 +0200

nohz: Include local CPU in full dynticks global kick

tick_nohz_full_kick_all() is useful to notify all full dynticks
CPUs that there is a system state change to checkout before
re-evaluating the need for the tick.

Unfortunately this is implemented using smp_call_function_many()
that ignores the local CPU. This CPU also needs to re-evaluate
the tick.

on_each_cpu_mask() is not useful either because we don't want to
re-evaluate the tick state in place but asynchronously from an IPI
to avoid messing up with any random locking scenario.

So lets call tick_nohz_full_kick() from tick_nohz_full_kick_all()
so that the usual irq work takes care of it.

Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Li Zhong <zhong@xxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Kevin Hilman <khilman@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1375460996-16329-4-git-send-email-fweisbec@xxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
kernel/time/tick-sched.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index adea6fc3..3612fc7 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -246,6 +246,7 @@ void tick_nohz_full_kick_all(void)
preempt_disable();
smp_call_function_many(tick_nohz_full_mask,
nohz_full_kick_ipi, NULL, false);
+ tick_nohz_full_kick();
preempt_enable();
}

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