diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2016-12-15 11:44:28 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-01-14 11:29:43 +0100 |
| commit | 12907fbb1a691807bb0420a27126e15934cb7954 (patch) | |
| tree | 14ba1797a6e24d566513b368c59b13948130dc40 /arch/x86/kernel | |
| parent | cb42c9a3ebbbb23448c3f9a25417fae6309b1a92 (diff) | |
| download | linux-12907fbb1a691807bb0420a27126e15934cb7954.tar.bz2 | |
sched/clock, clocksource: Add optional cs::mark_unstable() method
PeterZ reported that we'd fail to mark the TSC unstable when the
clocksource watchdog finds it unsuitable.
Allow a clocksource to run a custom action when its being marked
unstable and hook up the TSC unstable code.
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/tsc.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index be3a49ee0356..c8174c815d83 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1106,6 +1106,16 @@ static u64 read_tsc(struct clocksource *cs) return (u64)rdtsc_ordered(); } +static void tsc_cs_mark_unstable(struct clocksource *cs) +{ + if (tsc_unstable) + return; + tsc_unstable = 1; + clear_sched_clock_stable(); + disable_sched_clock_irqtime(); + pr_info("Marking TSC unstable due to clocksource watchdog\n"); +} + /* * .mask MUST be CLOCKSOURCE_MASK(64). See comment above read_tsc() */ @@ -1118,6 +1128,7 @@ static struct clocksource clocksource_tsc = { CLOCK_SOURCE_MUST_VERIFY, .archdata = { .vclock_mode = VCLOCK_TSC }, .resume = tsc_resume, + .mark_unstable = tsc_cs_mark_unstable, }; void mark_tsc_unstable(char *reason) |