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From:   Namhyung Kim <namhyung@kernel.org>
Date:   Fri, 16 Dec 2022 10:08:50 -0800
Message-ID: <CAM9d7ciS3H=2OVGGiNg5N6NeyZtfSE6D5kCHmQu_Otem4ByuuA@mail.gmail.com>
Subject: Re: [PATCH 2/9] perf report: Ignore SIGPIPE for srcline
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        linux-perf-users@vger.kernel.org,
        Milian Wolff <milian.wolff@kdab.com>,
        Leo Yan <leo.yan@linaro.org>
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Hi Andi,

On Thu, Dec 15, 2022 at 11:25 PM Andi Kleen <ak@linux.intel.com> wrote:
>
>
> On 12/15/2022 9:28 PM, Namhyung Kim wrote:
> > It can get SIGPIPE when it uses an external addr2line process and the
> > process was terminated unexpectedly.  Let's ignore the signal and move
> > on to the next sample.  The sample will get the default srcline value
> > anyway.
>
>
> That's a bit dangerous -- if perf report output is piped to something
> else you really want to stop on SIGPIPE.

Maybe we can handle the pipe write errors gracefully, but it'd require
more changes in many places.

>
> You would need to find a way to distinguish those cases.

Hmm.. ok.  I guess we can just drop this for now.  With checking
the .debug_line section, problematic cases should be gone mostly.

Thanks,
Namhyung