Re: [PATCH 1/3] drivers/perf: hisi: Consolidate uncore PMU cpuhp states

From: Yushan Wang

Date: Thu Jul 30 2026 - 22:56:54 EST




On 7/27/2026 8:41 PM, Robin Murphy wrote:
> On 24/07/2026 3:52 am, Yushan Wang wrote:
>> Every HiSilicon uncore PMU driver allocates its own static cpuhp state
>> even though they all register identical online/offline callbacks. This
>> wastes slots in the cpuhp state enum and needlessly fragments the
>> hotplug state space.
>>
>> Move the cpuhp state setup into the shared hisi_uncore_pmu framework:
>> register a single dynamic state (CPUHP_AP_ONLINE_DYN) at framework
>> module init and export it for all HiSilicon uncore PMU drivers to use.
>> Drop the now-unused static CPUHP_AP_PERF_ARM_HISI_* entries from
>> include/linux/cpuhotplug.h.
>>
>> The L3C PMU driver keeps a private dynamic state because it has its own
>> hotplug callbacks for migrating multiple per-CPU interrupt affinities,
>> but switches from its former static slot to CPUHP_AP_ONLINE_DYN for
>> consistency.
>>
>> No intended functional changes.
>>
>> Signed-off-by: Yushan Wang <wangyushan12@xxxxxxxxxx>
>> ---
>>   drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c  | 34 +++---------------
>>   drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c | 34 +++---------------
>>   drivers/perf/hisilicon/hisi_uncore_hha_pmu.c  | 34 +++---------------
>>   drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c  | 21 +++++------
>>   drivers/perf/hisilicon/hisi_uncore_mn_pmu.c   | 35 ++----------------
>>   drivers/perf/hisilicon/hisi_uncore_noc_pmu.c  | 35 ++----------------
>>   drivers/perf/hisilicon/hisi_uncore_pa_pmu.c   | 34 +++---------------
>>   drivers/perf/hisilicon/hisi_uncore_pmu.c      | 25 +++++++++++++
>>   drivers/perf/hisilicon/hisi_uncore_pmu.h      |  2 ++
>>   drivers/perf/hisilicon/hisi_uncore_sllc_pmu.c | 34 +++---------------
>>   drivers/perf/hisilicon/hisi_uncore_uc_pmu.c   | 36 ++-----------------
>>   include/linux/cpuhotplug.h                    |  6 ----
>>   12 files changed, 67 insertions(+), 263 deletions(-)
>
> Neat! Seems like a pretty nice win already, plus it only makes a conversion easier if my generic hotplug idea takes off :)
>
> Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx> 
>
Thanks for review, hisi pmu drivers can be the first users for it ;)