4.16-stable review patch. If anyone has any objections, please let me know.
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From: Peter Zijlstra peterz@infradead.org
commit e3b4f79025e0a4eb7e2a2c7d24dadfa1e38893b0 upstream.
mark_tsc_unstable() also needs to affect tsc_early, Now that clocksource_mark_unstable() can be used on a clocksource irrespective of its registration state, use it on both tsc_early and tsc.
This does however require cs->list to be initialized empty, otherwise it cannot tell the registation state before registation.
Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Diego Viola diego.viola@gmail.com Reviewed-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.533326547@infradead.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kernel/tsc.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
--- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1067,6 +1067,7 @@ static struct clocksource clocksource_ts .resume = tsc_resume, .mark_unstable = tsc_cs_mark_unstable, .tick_stable = tsc_cs_tick_stable, + .list = LIST_HEAD_INIT(clocksource_tsc_early.list), };
/* @@ -1086,6 +1087,7 @@ static struct clocksource clocksource_ts .resume = tsc_resume, .mark_unstable = tsc_cs_mark_unstable, .tick_stable = tsc_cs_tick_stable, + .list = LIST_HEAD_INIT(clocksource_tsc.list), };
void mark_tsc_unstable(char *reason) @@ -1098,13 +1100,9 @@ void mark_tsc_unstable(char *reason) clear_sched_clock_stable(); disable_sched_clock_irqtime(); pr_info("Marking TSC unstable due to %s\n", reason); - /* Change only the rating, when not registered */ - if (clocksource_tsc.mult) { - clocksource_mark_unstable(&clocksource_tsc); - } else { - clocksource_tsc.flags |= CLOCK_SOURCE_UNSTABLE; - clocksource_tsc.rating = 0; - } + + clocksource_mark_unstable(&clocksource_tsc_early); + clocksource_mark_unstable(&clocksource_tsc); }
EXPORT_SYMBOL_GPL(mark_tsc_unstable);