From d4bdd0b21c7652a8271f873cc755486b255c1bbd Mon Sep 17 00:00:00 2001 From: Ulrich Obergfell Date: Fri, 4 Sep 2015 15:45:21 -0700 Subject: [PATCH] watchdog: use park/unpark functions in update_watchdog_all_cpus() Remove update_watchdog() and restart_watchdog_hrtimer() since these functions are no longer needed. Changes of parameters such as the sample period are honored at the time when the watchdog threads are being unparked. Signed-off-by: Ulrich Obergfell Reviewed-by: Aaron Tomlin Cc: Guenter Roeck Cc: Don Zickus Cc: Ulrich Obergfell Cc: Jiri Olsa Cc: Michal Hocko Cc: Stephane Eranian Cc: Chris Metcalf Cc: Frederic Weisbecker Cc: Peter Zijlstra Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/watchdog.c | 40 ++-------------------------------------- 1 file changed, 2 insertions(+), 38 deletions(-) diff --git a/kernel/watchdog.c b/kernel/watchdog.c index e6eb5b697212..eb8f94b50101 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -745,46 +745,10 @@ void watchdog_resume(void) mutex_unlock(&watchdog_proc_mutex); } -static void restart_watchdog_hrtimer(void *info) -{ - struct hrtimer *hrtimer = raw_cpu_ptr(&watchdog_hrtimer); - int ret; - - /* - * No need to cancel and restart hrtimer if it is currently executing - * because it will reprogram itself with the new period now. - * We should never see it unqueued here because we are running per-cpu - * with interrupts disabled. - */ - ret = hrtimer_try_to_cancel(hrtimer); - if (ret == 1) - hrtimer_start(hrtimer, ns_to_ktime(sample_period), - HRTIMER_MODE_REL_PINNED); -} - -static void update_watchdog(int cpu) -{ - /* - * Make sure that perf event counter will adopt to a new - * sampling period. Updating the sampling period directly would - * be much nicer but we do not have an API for that now so - * let's use a big hammer. - * Hrtimer will adopt the new period on the next tick but this - * might be late already so we have to restart the timer as well. - */ - watchdog_nmi_disable(cpu); - smp_call_function_single(cpu, restart_watchdog_hrtimer, NULL, 1); - watchdog_nmi_enable(cpu); -} - static void update_watchdog_all_cpus(void) { - int cpu; - - get_online_cpus(); - for_each_watchdog_cpu(cpu) - update_watchdog(cpu); - put_online_cpus(); + watchdog_park_threads(); + watchdog_unpark_threads(); } static int watchdog_enable_all_cpus(void) -- 2.20.1