Subject: Re: [RFC PATCH 1/1] perf arm64: Implement --topdown with metrics
To:     Andrew Kilroy <andrew.kilroy@arm.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-perf-users@vger.kernel.org" <linux-perf-users@vger.kernel.org>,
        "acme@kernel.org" <acme@kernel.org>
CC:     Will Deacon <will@kernel.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Leo Yan <leo.yan@linaro.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        "Namhyung Kim" <namhyung@kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>
References: <4c375d34-bf20-496d-22fc-aed8597126e2@huawei.com>
 <20211214184240.24215-1-andrew.kilroy@arm.com>
 <20211214184240.24215-2-andrew.kilroy@arm.com>
From:   John Garry <john.garry@huawei.com>
Message-ID: <48437bee-9c39-38ba-e990-ba9a6a5378b4@huawei.com>
Date:   Fri, 17 Dec 2021 10:19:31 +0000
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.12.1
MIME-Version: 1.0
In-Reply-To: <20211214184240.24215-2-andrew.kilroy@arm.com>
Content-Type: text/plain; charset="gbk"; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 14/12/2021 18:42, Andrew Kilroy wrote:
> This patch implements the --topdown option by making use of metrics to
> dictate what counters are obtained in order to show the various topdown
> columns, e.g.  Frontend Bound, Backend Bound, Retiring and Bad
> Speculation.
> 
> The MetricGroup name is used to identify which set of metrics are to be
> shown.  For the moment use TopDownL1 and enable for arm64
> 
> Signed-off-by: Andrew Kilroy<andrew.kilroy@arm.com>

This works in that it gives results, but does not supply the same output 
format as for x86 nor has same restrictions in usage (-a commandline 
required, for example, below).

For my x86 broadwell:

john@localhost:~/linux/tools/perf> sudo ./perf stat --topdown  sleep 1
top down event configuration requires system-wide mode (-a)

john@localhost:~/linux/tools/perf> sudo ./perf stat --topdown -a sleep 1
Performance counter stats for 'system wide':

                                    retiring      bad speculation 
frontend bound        backend bound
S0-D0-C0           2                29.2%                 6.3% 
      37.4%                27.1%
S0-D0-C1           2                20.4%                 6.2% 
      42.1%                31.3%

       0.998007338 seconds time elapsed

john@localhost:~/linux/tools/perf>

---

Then my arm64 hip08 platform:

john@debian:~/kernel-dev/tools/perf$ sudo ./perf stat  --topdown sleep 1

  Performance counter stats for 'sleep 1':

             retiring      bad_speculation        backend_bound 
frontend_bound
                 0.19                 0.17                 0.27 
        0.37

        1.000832714 seconds time elapsed

        0.000891000 seconds user
        0.000000000 seconds sys

And there is no colouring for results which are above/below standard 
thresholds (see stat-shadow.c:get_radio_color()).

My impression is that we're not plugging the results from 
metricgroup__parse_groups_to_evlist() into the --topdown print 
functionality properly.

Thanks,
John