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

Andrew Jones
2023-05-31T13:54:38Z

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.

>
> 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>