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Date: Mon, 27 Nov 2023 18:53:19 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>, Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>, Mark Rutland <mark.rutland@arm.com>,
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Subject: Re: [PATCH v4 01/53] perf comm: Use regular mutex
Message-ID: <ZWUPz6ETFEBsrDkZ@kernel.org>
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Em Sun, Nov 05, 2023 at 09:31:47AM -0800, Namhyung Kim escreveu:
> Hi Ian,
> 
> On Thu, Nov 2, 2023 at 10:58 AM Ian Rogers <irogers@google.com> wrote:
> >
> > The rwsem is only after used for writing so switch to a mutex that has
> > better error checking.
> 
> Hmm.. ok.  It doesn't make sense to use rwsem without readers.

Well, the only reader is a findnew method, that will primarily read,
but possibly write if it doesn't find it there, so converting to a
regular mutex seems sensible.

- Arnaldo
 
> > Fixes: 7a8f349e9d14 ("perf rwsem: Add debug mode that uses a mutex")
> 
> But I'm not sure this is a fix.  Other than that,

Yeah, agreed, will remove the fixes.
 
> > Signed-off-by: Ian Rogers <irogers@google.com>
> 
> Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,

- Arnaldo