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| author |   Thomas Gleixner <tglx@linutronix.de> | 2020-02-07 13:38:54 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-02-17 14:40:22 +0100 |
| commit | eec399dd862762b9594df3659f15839a4e12f17a (patch) | |
| tree | 2ad42d36c099f2ec9b7eceff537281d0bad7c690 /arch/x86/kernel/tsc.c | |
| parent | clocksource: Cleanup struct clocksource and documentation (diff) | |
| download | linux-dev-eec399dd862762b9594df3659f15839a4e12f17a.tar.xz linux-dev-eec399dd862762b9594df3659f15839a4e12f17a.zip | |
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 <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> (Hyper-V parts)
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Link: https://lkml.kernel.org/r/20200207124402.934519777@linutronix.de
Diffstat (limited to 'arch/x86/kernel/tsc.c')
| -rw-r--r-- | arch/x86/kernel/tsc.c | 32 |
1 files changed, 20 insertions, 12 deletions
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, |