linux-kernel - Re: [PATCH v3 09/18] perf ui: Update use of pthread mutex

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Message-ID: <CAM9d7ciroc1XzRL+W34D5G7kCp4KCzRxjyRqnO2OXj=-ZaMTLQ@mail.gmail.com>
Date:   Fri, 26 Aug 2022 13:40:10 -0700
From:   Namhyung Kim <namhyung@...nel.org>
To:     Adrian Hunter <adrian.hunter@...el.com>
Cc:     Ian Rogers <irogers@...gle.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
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Subject: Re: [PATCH v3 09/18] perf ui: Update use of pthread mutex

On Fri, Aug 26, 2022 at 12:21 PM Adrian Hunter <adrian.hunter@...el.com> wrote:
>
> On 26/08/22 22:00, Namhyung Kim wrote:
> > On Fri, Aug 26, 2022 at 11:53 AM Adrian Hunter <adrian.hunter@...el.com> wrote:
> >> Below seems adequate for now, at least logically, but maybe it
> >> would confuse clang thread-safety analysis?
> >
> > I think it's not just about locks, the exit_browser should bail out early
> > if the setup code was not called.
>
> In those cases, use_browser is 0 or -1 unless someone has inserted
> an invalid perf config like "tui.script=on" or "gtk.script=on".
> So currently, in cases where exit_browser() is called without
> setup_browser(), it does nothing.  Which means it is only the
> unconditional mutex_destroy() that needs to be conditional.

Yeah there's a possibility that it can be called with > 0 use_browser
on some broken config or something.  So I think it's safer and better
for future changes.

Thanks,
Namhyung