From: Thomas Gleixner Date: Tue, 12 Sep 2017 19:37:22 +0000 (+0200) Subject: watchdog/hardlockup/perf: Simplify deferred event destroy X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a33d44843d4574ec05bec39527d8a87b7af2072c;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git watchdog/hardlockup/perf: Simplify deferred event destroy Now that all functionality is properly serialized against CPU hotplug, remove the extra per cpu storage which holds the disabled events for cleanup. The core makes sure that cleanup happens before new events are created. Signed-off-by: Thomas Gleixner Reviewed-by: Don Zickus Cc: Andrew Morton Cc: Borislav Petkov Cc: Chris Metcalf Cc: Linus Torvalds Cc: Nicholas Piggin Cc: Peter Zijlstra Cc: Sebastian Siewior Cc: Ulrich Obergfell Link: http://lkml.kernel.org/r/20170912194148.340708074@linutronix.de Signed-off-by: Ingo Molnar --- diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c index 509bb6b59c41..b2931154b5f2 100644 --- a/kernel/watchdog_hld.c +++ b/kernel/watchdog_hld.c @@ -21,7 +21,6 @@ static DEFINE_PER_CPU(bool, hard_watchdog_warn); static DEFINE_PER_CPU(bool, watchdog_nmi_touch); static DEFINE_PER_CPU(struct perf_event *, watchdog_ev); -static DEFINE_PER_CPU(struct perf_event *, dead_event); static struct cpumask dead_events_mask; static unsigned long hardlockup_allcpu_dumped; @@ -204,8 +203,6 @@ void hardlockup_detector_perf_disable(void) if (event) { perf_event_disable(event); - this_cpu_write(watchdog_ev, NULL); - this_cpu_write(dead_event, event); cpumask_set_cpu(smp_processor_id(), &dead_events_mask); watchdog_cpus--; } @@ -221,9 +218,9 @@ void hardlockup_detector_perf_cleanup(void) int cpu; for_each_cpu(cpu, &dead_events_mask) { - struct perf_event *event = per_cpu(dead_event, cpu); + struct perf_event *event = per_cpu(watchdog_ev, cpu); - per_cpu(dead_event, cpu) = NULL; + per_cpu(watchdog_ev, cpu) = NULL; perf_event_release_kernel(event); } cpumask_clear(&dead_events_mask);