The following commit has been merged into the timers/core branch of tip:
Commit-ID: 49a101d7169c7729c7bab6b2f896faae34bd6c3d
Gitweb: https://git.kernel.org/tip/49a101d7169c7729c7bab6b2f896faae34bd6c3d
Author: Christophe Leroy <christophe.leroy@xxxxxx>
AuthorDate: Thu, 16 Jan 2020 17:58:27
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 16 Jan 2020 21:24:46 +01:00
lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres()
Only perform READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res) for
HRES and RAW clocks.
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/7ac2f0d21652f95e2bbdfa6bd514ae6c7caf53ab.1579196675.git.christophe.leroy@xxxxxx
---
lib/vdso/gettimeofday.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index f342ac1..f8b8ec5 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -312,7 +312,6 @@ static __maybe_unused
int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
{
const struct vdso_data *vd = __arch_get_vdso_data();
- u64 hrtimer_res;
u32 msk;
u64 ns;
@@ -323,7 +322,6 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
if (IS_ENABLED(CONFIG_TIME_NS) && vd->clock_mode == VCLOCK_TIMENS)
vd = __arch_get_timens_vdso_data();
- hrtimer_res = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
/*
* Convert the clockid to a bitmask and use it to check which
* clocks are handled in the VDSO directly.
@@ -333,7 +331,7 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
/*
* Preserves the behaviour of posix_get_hrtimer_res().
*/
- ns = hrtimer_res;
+ ns = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
} else if (msk & VDSO_COARSE) {
/*
* Preserves the behaviour of posix_get_coarse_res().
|