diff options
| author | Michael Kelley <mikelley@microsoft.com> | 2021-03-02 13:38:20 -0800 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2021-03-08 17:33:00 +0000 |
| commit | eb3e1d370b4c57be1acbb9de51a7deaa036eff4b (patch) | |
| tree | d476d56fb76984e4a0eaa2d4efe0a4990133c85f /drivers/clocksource | |
| parent | e4ab4658f1cff14c82202132f7af2cb5c2741469 (diff) | |
clocksource/drivers/hyper-v: Handle sched_clock differences inline
While the Hyper-V Reference TSC code is architecture neutral, the
pv_ops.time.sched_clock() function is implemented for x86/x64, but not
for ARM64. Current code calls a utility function under arch/x86 (and
coming, under arch/arm64) to handle the difference.
Change this approach to handle the difference inline based on whether
GENERIC_SCHED_CLOCK is present. The new approach removes code under
arch/* since the difference is tied more to the specifics of the Linux
implementation than to the architecture.
No functional change.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1614721102-2241-9-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/clocksource')
| -rw-r--r-- | drivers/clocksource/hyperv_timer.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c index 06984fa11936..10eb5c645141 100644 --- a/drivers/clocksource/hyperv_timer.c +++ b/drivers/clocksource/hyperv_timer.c @@ -423,6 +423,30 @@ static struct clocksource hyperv_cs_msr = { .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; +/* + * Reference to pv_ops must be inline so objtool + * detection of noinstr violations can work correctly. + */ +#ifdef CONFIG_GENERIC_SCHED_CLOCK +static __always_inline void hv_setup_sched_clock(void *sched_clock) +{ + /* + * We're on an architecture with generic sched clock (not x86/x64). + * The Hyper-V sched clock read function returns nanoseconds, not + * the normal 100ns units of the Hyper-V synthetic clock. + */ + sched_clock_register(sched_clock, 64, NSEC_PER_SEC); +} +#elif defined CONFIG_PARAVIRT +static __always_inline void hv_setup_sched_clock(void *sched_clock) +{ + /* We're on x86/x64 *and* using PV ops */ + pv_ops.time.sched_clock = sched_clock; +} +#else /* !CONFIG_GENERIC_SCHED_CLOCK && !CONFIG_PARAVIRT */ +static __always_inline void hv_setup_sched_clock(void *sched_clock) {} +#endif /* CONFIG_GENERIC_SCHED_CLOCK */ + static bool __init hv_init_tsc_clocksource(void) { u64 tsc_msr; |