[PATCH 0/2] arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO
Kevin Brodsky
kevin.brodsky at arm.com
Mon May 9 05:36:59 PDT 2016
Hi,
This small series adds support for CLOCK_MONOTONIC_RAW to
clock_gettime() (and clock_getres()) in the arm64 vDSO. This should make
calls to clock_gettime() with CLOCK_MONOTONIC_RAW just as fast as
CLOCK_MONOTONIC and such, instead of falling back to the significantly
slower syscall.
Given that gettimeofday.S is already quite difficult to understand, and
directly adding MONOTONIC_RAW support makes it even more so, the first
patch refactors it to make it simpler, and save a few instructions along
the way. The second patch actually adds support for MONOTONIC_RAW, which
is made quite easy by the refactoring.
Thanks,
Kevin
Kevin Brodsky (2):
arm64: Refactor vDSO time functions
arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO
arch/arm64/include/asm/vdso_datapage.h | 8 +-
arch/arm64/kernel/asm-offsets.c | 6 +-
arch/arm64/kernel/vdso.c | 8 +-
arch/arm64/kernel/vdso/gettimeofday.S | 317 ++++++++++++++++++++-------------
4 files changed, 215 insertions(+), 124 deletions(-)
--
2.8.0
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