From eec399dd862762b9594df3659f15839a4e12f17a Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 7 Feb 2020 13:38:54 +0100 Subject: x86/vdso: Move VDSO clocksource state tracking to callback All architectures which use the generic VDSO code have their own storage for the VDSO clock mode. That's pointless and just requires duplicate code. X86 abuses the function which retrieves the architecture specific clock mode storage to mark the clocksource as used in the VDSO. That's silly because this is invoked on every tick when the VDSO data is updated. Move this functionality to the clocksource::enable() callback so it gets invoked once when the clocksource is installed. This allows to make the clock mode storage generic. Signed-off-by: Thomas Gleixner Reviewed-by: Michael Kelley (Hyper-V parts) Reviewed-by: Vincenzo Frascino (VDSO parts) Acked-by: Juergen Gross (Xen parts) Link: https://lkml.kernel.org/r/20200207124402.934519777@linutronix.de --- arch/x86/kernel/tsc.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) (limited to 'arch/x86/kernel/tsc.c') diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 7e322e2daaf5..742da141a30a 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1108,17 +1108,24 @@ static void tsc_cs_tick_stable(struct clocksource *cs) sched_clock_tick_stable(); } +static int tsc_cs_enable(struct clocksource *cs) +{ + vclocks_set_used(VCLOCK_TSC); + return 0; +} + /* * .mask MUST be CLOCKSOURCE_MASK(64). See comment above read_tsc() */ static struct clocksource clocksource_tsc_early = { - .name = "tsc-early", - .rating = 299, - .read = read_tsc, - .mask = CLOCKSOURCE_MASK(64), - .flags = CLOCK_SOURCE_IS_CONTINUOUS | + .name = "tsc-early", + .rating = 299, + .read = read_tsc, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_MUST_VERIFY, - .archdata = { .vclock_mode = VCLOCK_TSC }, + .archdata = { .vclock_mode = VCLOCK_TSC }, + .enable = tsc_cs_enable, .resume = tsc_resume, .mark_unstable = tsc_cs_mark_unstable, .tick_stable = tsc_cs_tick_stable, @@ -1131,14 +1138,15 @@ static struct clocksource clocksource_tsc_early = { * been found good. */ static struct clocksource clocksource_tsc = { - .name = "tsc", - .rating = 300, - .read = read_tsc, - .mask = CLOCKSOURCE_MASK(64), - .flags = CLOCK_SOURCE_IS_CONTINUOUS | + .name = "tsc", + .rating = 300, + .read = read_tsc, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_VALID_FOR_HRES | CLOCK_SOURCE_MUST_VERIFY, - .archdata = { .vclock_mode = VCLOCK_TSC }, + .archdata = { .vclock_mode = VCLOCK_TSC }, + .enable = tsc_cs_enable, .resume = tsc_resume, .mark_unstable = tsc_cs_mark_unstable, .tick_stable = tsc_cs_tick_stable, -- cgit