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@xxxxxxxxxxxx> > --- > 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@xxxxxxxxxxxxxxxx>