Re: [PATCH v2 0/2] perf: arm_pmuv3: Don't use PMCCNTR_EL0 on SMT cores

Will Deacon
2025-09-18T16:43:57Z

On Wed, 20 Aug 2025 16:45:32 +0800, Yicong Yang wrote:
> This patchset fixed CPU_CYCLES counting on SMT system. CPU_CYCLES can use
> PMCCNTR_EL0 which will count the hardware processor clock rather than the
> PE clock (ARM DDI0487 L.b D13.1.3) on SMT cores which fails the users
> expectation as CPU_CYCLES (0x0011) is defined to count on each PE cycles.
> Fix this by avoid using PMCCNTR_EL0 on SMT cores when counting CPU_CYCLES.
>
> Changes since v1:
> - remove redundant comment and add tags on Patch 1/2
> - detect the SMT implementation during PMU probe rather than runtime
> Link: https://lore.kernel.org/linux-arm-kernel/20250812080830.20796-1-yangyicong@huawei.com/
>
> [...]

Applied first patch to will (for-next/perf), thanks!

[1/2] perf: arm_pmuv3: Factor out PMCCNTR_EL0 use conditions
https://git.kernel.org/will/c/f8f89e8cf3d6

Cheers,
--
Will