From 24f73b99716a9cd8cbb345c41ced6b3b5ed94006 Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 13 Jul 2016 17:16:59 +0000 Subject: timers/core: Convert to hotplug state machine When tearing down, call timers_dead_cpu() before notify_dead(). There is a hidden dependency between: - timers - block multiqueue - rcutree If timers_dead_cpu() comes later than blk_mq_queue_reinit_notify() that latter function causes a RCU stall. Signed-off-by: Richard Cochran Signed-off-by: Anna-Maria Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: John Stultz Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rasmus Villemoes Cc: Thomas Gleixner Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153337.566790058@linutronix.de Signed-off-by: Ingo Molnar --- kernel/cpu.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/cpu.c') diff --git a/kernel/cpu.c b/kernel/cpu.c index 85500e7fe238..e1017d92d308 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1195,6 +1195,11 @@ static struct cpuhp_step cpuhp_bp_states[] = { .startup = hrtimers_prepare_cpu, .teardown = hrtimers_dead_cpu, }, + [CPUHP_TIMERS_DEAD] = { + .name = "timers dead", + .startup = NULL, + .teardown = timers_dead_cpu, + }, /* * Preparatory and dead notifiers. Will be replaced once the notifiers * are converted to states. -- cgit v1.2.3