diff options
| author | Vincenzo Frascino <vincenzo.frascino@arm.com> | 2019-04-16 17:14:30 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-31 06:48:23 -0700 |
| commit | 9f641ee2b749d57b4672e4c28f4dba9523923ac4 (patch) | |
| tree | b99ce92c05ff07c1f10c5f559b7bfca5d828153d /arch/arm64/include | |
| parent | f64615a8573059ad5c0602266a8b8c9f7ecaff02 (diff) | |
arm64: vdso: Fix clock_getres() for CLOCK_REALTIME
[ Upstream commit 81fb8736dd81da3fe94f28968dac60f392ec6746 ]
clock_getres() in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().
In particular, posix_get_hrtimer_res() does:
sec = 0;
ns = hrtimer_resolution;
where 'hrtimer_resolution' depends on whether or not high resolution
timers are enabled, which is a runtime decision.
The vDSO incorrectly returns the constant CLOCK_REALTIME_RES. Fix this
by exposing 'hrtimer_resolution' in the vDSO datapage and returning that
instead.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[will: Use WRITE_ONCE(), move adr off COARSE path, renumber labels, use 'w' reg]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/vdso_datapage.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/vdso_datapage.h b/arch/arm64/include/asm/vdso_datapage.h index 2b9a63771eda..f89263c8e11a 100644 --- a/arch/arm64/include/asm/vdso_datapage.h +++ b/arch/arm64/include/asm/vdso_datapage.h @@ -38,6 +38,7 @@ struct vdso_data { __u32 tz_minuteswest; /* Whacky timezone stuff */ __u32 tz_dsttime; __u32 use_syscall; + __u32 hrtimer_res; }; #endif /* !__ASSEMBLY__ */ |