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Date:   Mon, 14 Sep 2020 22:47:01 +0200
From:   Jiri Olsa <jolsa@redhat.com>
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Jiri Olsa <jolsa@kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Ingo Molnar <mingo@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Michael Petlan <mpetlan@redhat.com>,
        Song Liu <songliubraving@fb.com>,
        "Frank Ch. Eigler" <fche@redhat.com>,
        Ian Rogers <irogers@google.com>,
        Stephane Eranian <eranian@google.com>,
        Alexey Budankov <alexey.budankov@linux.intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Adrian Hunter <adrian.hunter@intel.com>
Subject: Re: [PATCH 05/26] perf tools: Add build_id__is_defined function
Message-ID: <20200914204701.GZ1714160@krava>
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 <20200913210313.1985612-6-jolsa@kernel.org>
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On Mon, Sep 14, 2020 at 02:44:35PM +0900, Namhyung Kim wrote:
> On Mon, Sep 14, 2020 at 6:05 AM Jiri Olsa <jolsa@kernel.org> wrote:
> >
> > Adding build_id__is_defined helper to check build id
> > is defined and is != zero build id.
> >
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > ---
> >  tools/perf/util/build-id.c | 11 +++++++++++
> >  tools/perf/util/build-id.h |  1 +
> >  2 files changed, 12 insertions(+)
> >
> > diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
> > index 31207b6e2066..bdee4e08e60d 100644
> > --- a/tools/perf/util/build-id.c
> > +++ b/tools/perf/util/build-id.c
> > @@ -902,3 +902,14 @@ bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
> >
> >         return ret;
> >  }
> > +
> > +bool build_id__is_defined(const u8 *build_id)
> > +{
> > +       static u8 zero[BUILD_ID_SIZE];
> > +       int err = 0;
> > +
> > +       if (build_id)
> > +               err = memcmp(build_id, &zero, BUILD_ID_SIZE);
> > +
> > +       return err ? true : false;
> > +}
> 
> I think this is a bit confusing.. How about this?
> 
>   bool ret = false;
>   if (build_id)
>       ret = memcmp(...);
>   return ret;

ok

> 
> Or, it can be a oneliner..

everything can be oneliner ;-)

thanks,
jirka