Re: [PATCH V3 1/5] perf/core: Add PERF_SAMPLE_WEIGHT_STRUCT

[Namhyung Kim]

On Fri, Feb 5, 2021 at 12:24 AM Liang, Kan <kan.liang@xxxxxxxxxxxxxxx> wrote:
>
> On 2/4/2021 9:00 AM, Namhyung Kim wrote:
> > Hi Kan,
> >
> > On Sat, Jan 30, 2021 at 2:25 AM Liang, Kan <kan.liang@xxxxxxxxxxxxxxx> wrote:
> > [SNIP]
> >> diff --git a/include/uapi/linux/perf_event.h
> >> b/include/uapi/linux/perf_event.h
> >> index b15e344..c50718a 100644
> >> --- a/include/uapi/linux/perf_event.h
> >> +++ b/include/uapi/linux/perf_event.h
> >> @@ -145,12 +145,14 @@ enum perf_event_sample_format {
> >>          PERF_SAMPLE_CGROUP                      = 1U << 21,
> >>          PERF_SAMPLE_DATA_PAGE_SIZE              = 1U << 22,
> >>          PERF_SAMPLE_CODE_PAGE_SIZE              = 1U << 23,
> >> +       PERF_SAMPLE_WEIGHT_STRUCT               = 1U << 24,
> >>
> >> -       PERF_SAMPLE_MAX = 1U << 24,             /* non-ABI */
> >> +       PERF_SAMPLE_MAX = 1U << 25,             /* non-ABI */
> >>
> >>          __PERF_SAMPLE_CALLCHAIN_EARLY           = 1ULL << 63, /* non-ABI; internal use */
> >>    };
> >>
> >> +#define PERF_SAMPLE_WEIGHT_TYPE        (PERF_SAMPLE_WEIGHT |
> >> PERF_SAMPLE_WEIGHT_STRUCT)
> >
> > I'm not sure you want to expose it in the uapi header as it's not
> > intended to be used IMHO.
> >
>
> I'm not sure I understood, but it's indeed used in the tool patch set.
>
> https://lore.kernel.org/lkml/1612296553-21962-6-git-send-email-kan.liang@xxxxxxxxxxxxxxx/

Well, it's not a big deal.. but I just worried if some users might do

  event.attr.sample_type = PERF_SAMPLE_WEIGHT_TYPE;

Thanks,
Namhyung