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From: Ian Rogers <irogers@google.com>
Date: Tue, 21 May 2024 10:13:07 -0700
Message-ID: <CAP-5=fXtahvLa5hFqdQpPyeHYsUNe=MkJBn8Yf5npNUvGJOU0w@mail.gmail.com>
Subject: Re: [PATCH v1] perf jevents: Autogenerate empty-pmu-events.c
To: John Garry <john.g.garry@oracle.com>
Cc: Weilin Wang <weilin.wang@intel.com>, Peter Zijlstra <peterz@infradead.org>, 
	Ingo Molnar <mingo@redhat.com>, Arnaldo Carvalho de Melo <acme@kernel.org>, Namhyung Kim <namhyung@kernel.org>, 
	Mark Rutland <mark.rutland@arm.com>, 
	Alexander Shishkin <alexander.shishkin@linux.intel.com>, Jiri Olsa <jolsa@kernel.org>, 
	Adrian Hunter <adrian.hunter@intel.com>, Kan Liang <kan.liang@linux.intel.com>, 
	Jing Zhang <renyu.zj@linux.alibaba.com>, Sandipan Das <sandipan.das@amd.com>, 
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
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On Tue, May 21, 2024 at 4:45=E2=80=AFAM John Garry <john.g.garry@oracle.com=
> wrote:
>
> On 20/05/2024 16:36, Ian Rogers wrote:
> >       }
> > +                ret =3D pmu_events_table__find_event_pmu(table, table_=
pmu, name, fn, data);
> > +                if (ret !=3D -1000)
> > +                        return ret;
> > +        }
> >           return -1000;
>
> what's -1000 meaning? It would be nice to use some standard error codes.

This is a pre-existing thing. 0 means continue and anything else
generally aborts a search, -1000 is used when searching multiple
tables to indicate not found in 1 table but potentially not all.

Commit 3d5045492ab2 ("perf pmu-events: Add
pmu_events_table__find_event()") added this [1], you were on the cc
list ;-) I think moving to a named constant would make this more
intention revealing so I'll add this to a v2 set.

Thanks,
Ian

[1] https://lore.kernel.org/r/20230824041330.266337-9-irogers@google.com

> Thanks,
> John
>
>