From cd2af07d823e5287cd6c91d54337348c2a873462 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 30 Apr 2018 12:00:13 +0200 Subject: clocksource: Consistent de-rate when marking unstable When a registered clocksource gets marked unstable the watchdog_kthread will de-rate and re-select the clocksource. Ensure it also de-rates when getting called on an unregistered clocksource. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Rafael J. Wysocki Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.594904898@infradead.org --- kernel/time/clocksource.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 935f39eb8aac..605656df16c4 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -152,12 +152,19 @@ static void __clocksource_unstable(struct clocksource *cs) cs->flags &= ~(CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_WATCHDOG); cs->flags |= CLOCK_SOURCE_UNSTABLE; - if (list_empty(&cs->list)) + /* + * If the clocksource is registered clocksource_watchdog_kthread() will + * re-rate and re-select. + */ + if (list_empty(&cs->list)) { + cs->rating = 0; return; + } if (cs->mark_unstable) cs->mark_unstable(cs); + /* kick clocksource_watchdog_kthread() */ if (finished_booting) schedule_work(&watchdog_work); } -- cgit v1.2.3