Re: [PATCH v2 01/10] perf: Fix wrong comment about default event_idx

Alexandre Ghiti
2023-06-15T07:11:09Z

On 31/05/2023 15:54, Andrew Jones wrote:
> On Fri, May 12, 2023 at 10:53:12AM +0200, Alexandre Ghiti wrote:
>> event_idx default implementation returns 0, not idx + 1.
> The comment was correct until commit c719f56092ad ("perf: Fix and clean
> up initialization of pmu::event_idx"). I'm not sure that warrants a fixes
> tag, but maybe a reference in the commit message.

You're right, I'll add a reference, I don't think it deserves a
backport, that's just a comment.

>> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
>> ---
>> include/linux/perf_event.h | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
>> index d5628a7b5eaa..56fe43b20966 100644
>> --- a/include/linux/perf_event.h
>> +++ b/include/linux/perf_event.h
>> @@ -442,7 +442,8 @@ struct pmu {
>>
>> /*
>> * Will return the value for perf_event_mmap_page::index for this event,
>> - * if no implementation is provided it will default to: event->hw.idx + 1.
>> + * if no implementation is provided it will default to 0 (see
>> + * perf_event_idx_default).
>> */
>> int (*event_idx) (struct perf_event *event); /*optional */
>>
>> --
>> 2.37.2
>>
> Otherwise,
>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks!