Re: [PATCH v3 05/10] perf/x86/rapl: Move cpumask variable to rapl_pmus struct

[Dhananjay Ugwekar]

Hello Peter,

On 7/1/2024 6:32 PM, Peter Zijlstra wrote:
> On Mon, Jun 24, 2024 at 05:59:02AM +0000, Dhananjay Ugwekar wrote:
>> This patch is in preparation for addition of per-core energy counter
>> support for AMD CPUs.
>>
>> Per-core energy counter PMU will need a separate cpumask. It seems like
>> a better approach to add the cpumask inside the rapl_pmus struct, instead
>> of creating another global cpumask variable for per-core PMU. This way, in
>> future, if there is a need for a new PMU with a different scope (e.g. CCD),
>> adding a new global cpumask variable won't be necessary.
>>
>> No functional change.
>>
>> Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@xxxxxxx>
>> ---
>>  arch/x86/events/rapl.c | 12 ++++++------
>>  1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/x86/events/rapl.c b/arch/x86/events/rapl.c
>> index e5e878146542..be139e9f9ee0 100644
>> --- a/arch/x86/events/rapl.c
>> +++ b/arch/x86/events/rapl.c
>> @@ -119,6 +119,7 @@ struct rapl_pmu {
>>  
>>  struct rapl_pmus {
>>  	struct pmu		pmu;
>> +	cpumask_t		cpumask;
>>  	unsigned int		nr_rapl_pmu;
>>  	struct rapl_pmu		*rapl_pmu[] __counted_by(nr_rapl_pmu);
>>  };
> 
> Yikes no, please use cpumask_var_t and alloc_cpumask_var() and friends.

Ah yes!, I did not know about this API, will use this in the next version.

Thanks,
Dhananjay