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Date:   Thu, 14 Sep 2023 07:40:41 +0100
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Subject: Re: [PATCH v3 2/3] perf pmus: Simplify perf_pmus__find_core_pmu()
Content-Language: en-US
To:     James Clark <james.clark@arm.com>,
        linux-perf-users@vger.kernel.org, irogers@google.com,
        acme@kernel.org
Cc:     Will Deacon <will@kernel.org>, Mike Leach <mike.leach@linaro.org>,
        Leo Yan <leo.yan@linaro.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Kan Liang <kan.liang@linux.intel.com>,
        Jing Zhang <renyu.zj@linux.alibaba.com>,
        Haixin Yu <yuhaixin.yhx@linux.alibaba.com>,
        Eduard Zingerman <eddyz87@gmail.com>,
        Ravi Bangoria <ravi.bangoria@amd.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230913153355.138331-1-james.clark@arm.com>
 <20230913153355.138331-3-james.clark@arm.com>
From:   John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
In-Reply-To: <20230913153355.138331-3-james.clark@arm.com>
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On 13/09/2023 16:33, James Clark wrote:
> Currently the while loop always either exits on the first iteration with
> a core PMU, or exits with NULL on heterogeneous systems or when not all
> CPUs are online.
> 
> Both of the latter behaviors are undesirable for platforms other than
> Arm so simplify it to always return the first core PMU, or NULL if none
> exist.
> 
> This behavior was depended on by the Arm version of
> pmu_metrics_table__find(), so the logic has been moved there instead.
> 
> Suggested-by: Ian Rogers <irogers@google.com>
> Reviewed-by: Ian Rogers <irogers@google.com>
> Signed-off-by: James Clark <james.clark@arm.com>

Reviewed-by: John Garry <john.g.garry@oracle.com>