Re: [PATCH 08/13] drivers/perf: apple_m1: Add Apple A18 Support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] drivers/perf: apple_m1: redundant a18_pmu_* aliases and unused macro
--

commit 96c1a110d959d59196297459a3c8bd2316dfaece
Author: Myria Sarvay <myrialsarvay@gmail.com>

drivers/perf: apple_m1: Add Apple A18 Support

This commit adds CPU PMU support for the Apple A18 (Tahiti) cores by
reusing the M4 PMU event mappings and callbacks.

> diff --git a/drivers/perf/apple_m1_cpu_pmu.c b/drivers/perf/apple_m1_cpu_pmu.c
> index bdbd138cf1db8..775f3d5aba7ea 100644
> --- a/drivers/perf/apple_m1_cpu_pmu.c
> +++ b/drivers/perf/apple_m1_cpu_pmu.c
> @@ -1149,12 +1149,23 @@ static int gen ## _pmu_ ## family ## _init(struct arm_pmu *cpu_pmu)				\
>  #define m4_pmu_set_event_filter		m3_pmu_set_event_filter
>  #define m4_pmu_format_attr_group	m3_pmu_format_attr_group
>  
> +#define a18_pmu_enable_event		m4_pmu_enable_event
> +#define a18_pmu_map_event		m4_pmu_map_event
> +#define a18_pmu_get_event_idx		m4_pmu_get_event_idx
> +#define a18_pmu_set_event_filter	m4_pmu_set_event_filter
> +#define a18_pmu_map_pmuv3_event		m4_pmu_map_pmuv3_event
> +#define a18_pmu_init_pmceid		m4_pmu_init_pmceid
> +#define a18_pmu_events_attr_group	m4_pmu_events_attr_group
> +#define a18_pmu_format_attr_group	m4_pmu_format_attr_group
> +
>  APPLE_PMU_INIT(m1, icestorm)
>  APPLE_PMU_INIT(m1, firestorm)
>  APPLE_PMU_INIT(m2, avalanche)
>  APPLE_PMU_INIT(m2, blizzard)
>  APPLE_PMU_INIT(m3, sawtooth)
>  APPLE_PMU_INIT(m3, everest)
> +APPLE_PMU_INIT(a18, tahiti_e)
> +APPLE_PMU_INIT(a18, tahiti_p)

[Severity: Low]
This isn't a bug, but since APPLE_PMU_INIT(gen, family) only uses the gen
argument to select the gen_pmu_* callbacks and attribute groups (while
cpu_pmu->name is constructed solely from family), are the a18_pmu_* alias
macros needed here?

Unlike m2 and m4, which define generation-specific callbacks or attribute
groups and only alias the remaining symbols from an earlier generation, a18
aliases every symbol to m4_pmu_*. In addition, a18_pmu_init_pmceid is never
used by APPLE_PMU_INIT() and expands to m4_pmu_init_pmceid, which does not
exist.

Could this use APPLE_PMU_INIT(m4, tahiti_e) and APPLE_PMU_INIT(m4, tahiti_p)
directly (with m4_pmu_tahiti_e_init and m4_pmu_tahiti_p_init in
m1_pmu_of_device_ids) and drop the a18_pmu_* macro definitions?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261103-m3-plus-pmu-events-v1-0-a8eb6c1139fe@gmail.com?part=8