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Message-ID: <dc07fcb8-9a7c-7f74-375f-99ce192c4f39@linux.intel.com>
Date:   Tue, 23 Aug 2022 17:10:55 +0200
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Subject: Re: [PATCH v1 1/2] perf stat: Clear reset_group for each stat run
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To:     Ian Rogers <irogers@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Kan Liang <kan.liang@linux.intel.com>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Stephane Eranian <eranian@google.com>
References: <20220822213352.75721-1-irogers@google.com>
From:   Andi Kleen <ak@linux.intel.com>
In-Reply-To: <20220822213352.75721-1-irogers@google.com>
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On 8/22/2022 11:33 PM, Ian Rogers wrote:
> If a weak group is broken then the reset_group flag remains set for
> the next run. Having reset_group set means the counter isn't created
> and ultimately a segfault.
>
> A simple reproduction of this is:
> perf stat -r2 -e '{cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles}:W
> which will be added as a test in the next patch.
>
> Fixes: 4804e0111662 ("perf stat: Use affinity for opening events")
> Signed-off-by: Ian Rogers <irogers@google.com>


Makes sense


Reviewed-by: Andi Kleen <ak@linux.intel.com>