[PATCH v2 0/3] Use CNTVCTSS_EL0 in gettimeofday()
Joey Gouly
joey.gouly at arm.com
Tue Aug 30 03:48:30 PDT 2022
Hi all,
This patchset adds support for using CNTVCTSS_EL0 in gettimeofday() in the vDSO.
This can improve the accuracy and efficiency of some applications that call
gettimeofday() a lot.
This has been tested on an internal platform and a publicly available platform
that has FEAT_ECV.
Changes since v1 [1]:
- Tidy up asm() statement in gettimeofday.h
- Move vdso patching before __apply_alternatives_multi_stop
Thanks,
Joey
[1]: https://lore.kernel.org/linux-arm-kernel/20220825102025.53916-1-joey.gouly@arm.com/
Joey Gouly (3):
arm64: module: move find_section to header
arm64: alternative: patch alternatives in the vDSO
arm64: vdso: use SYS_CNTVCTSS_EL0 for gettimeofday
arch/arm64/include/asm/module.h | 15 ++++++++++++
arch/arm64/include/asm/vdso.h | 3 +++
arch/arm64/include/asm/vdso/gettimeofday.h | 19 +++++++++++----
arch/arm64/kernel/alternative.c | 28 ++++++++++++++++++++++
arch/arm64/kernel/module.c | 15 ------------
arch/arm64/kernel/vdso.c | 3 ---
arch/arm64/kernel/vdso/vdso.lds.S | 7 ++++++
7 files changed, 68 insertions(+), 22 deletions(-)
--
2.17.1
More information about the linux-arm-kernel
mailing list