Re: [PATCH v3 3/7] perf vendor events: Add JSON metrics for CMN

From: Ian Rogers <irogers@google.com>
To: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: John Garry <john.g.garry@oracle.com>,
	Will Deacon <will@kernel.org>,
	Shuai Xue <xueshuai@linux.alibaba.com>,
	Robin Murphy <robin.murphy@arm.com>,
	James Clark <james.clark@arm.com>,
	Mike Leach <mike.leach@linaro.org>, Leo Yan <leo.yan@linaro.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Ilkka Koskinen <ilkka@os.amperecomputing.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org,
	Zhuo Song <zhuo.song@linux.alibaba.com>
Subject: Re: [PATCH v3 3/7] perf vendor events: Add JSON metrics for CMN
Date: Tue, 30 May 2023 18:18:31 -0700	[thread overview]
Message-ID: <CAP-5=fVF4wD0t5Sxa56-pPevv4_NqKOYEeqqRLFYPL7a3FSffA@mail.gmail.com> (raw)
In-Reply-To: <1685438374-33287-4-git-send-email-renyu.zj@linux.alibaba.com>

On Tue, May 30, 2023 at 2:19 AM Jing Zhang <renyu.zj@linux.alibaba.com> wrote:
>
> Add JSON metrics for arm CMN. Currently just add part of CMN PMU
> metrics which are general and compatible for any SoC and CMN-ANY.
>
> Signed-off-by: Jing Zhang <renyu.zj@linux.alibaba.com>
> ---
>  .../pmu-events/arch/arm64/arm/cmn/sys/metrics.json | 74 ++++++++++++++++++++++
>  tools/perf/pmu-events/jevents.py                   |  1 +
>  2 files changed, 75 insertions(+)
>  create mode 100644 tools/perf/pmu-events/arch/arm64/arm/cmn/sys/metrics.json
>
> diff --git a/tools/perf/pmu-events/arch/arm64/arm/cmn/sys/metrics.json b/tools/perf/pmu-events/arch/arm64/arm/cmn/sys/metrics.json
> new file mode 100644
> index 0000000..e70ac1a
> --- /dev/null
> +++ b/tools/perf/pmu-events/arch/arm64/arm/cmn/sys/metrics.json
> @@ -0,0 +1,74 @@
> +[
> +       {
> +               "MetricName": "slc_miss_rate",
> +               "BriefDescription": "The system level cache miss rate include.",

Nit, partial sentence?

> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "hnf_cache_miss / hnf_slc_sf_cache_access",
> +               "ScaleUnit": "100%",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "hnf_message_retry_rate",
> +               "BriefDescription": "HN-F message retry rate indicates whether a lack of credits is causing the bottlenecks.",
> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "hnf_pocq_retry / hnf_pocq_reqs_recvd",
> +               "ScaleUnit": "100%",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "sf_hit_rate",
> +               "BriefDescription": "Snoop filter hit rate can be used to measure the Snoop Filter efficiency.",

Nit, inconsistent capitalization?

> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "hnf_sf_hit / hnf_slc_sf_cache_access",
> +               "ScaleUnit": "100%",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "mc_message_retry_rate",
> +               "BriefDescription": "The memory controller request retries rate indicates whether the memory controller is the bottleneck.",
> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "hnf_mc_retries / hnf_mc_reqs",
> +               "ScaleUnit": "100%",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "rni_actual_read_bandwidth.all",
> +               "BriefDescription": "This event measure the actual bandwidth(MB/sec) that RN-I bridge sends to the interconnect.",

Nit, the MB/sec is in the ScaleUnit so could be dropped here.

> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "rnid_rxdat_flits * 32 / 1e6 / duration_time",
> +               "ScaleUnit": "1MB/s",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "rni_actual_write_bandwidth.all",
> +               "BriefDescription": "This event measures the actual write bandwidth(MB/sec) at RN-I bridges.",

Nit, same thing.

> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "rnid_txdat_flits * 32 / 1e6 / duration_time",
> +               "ScaleUnit": "1MB/s",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "rni_retry_rate",
> +               "BriefDescription": "RN-I bridge retry rate indicates whether the memory controller is the bottleneck.",
> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "rnid_txreq_flits_retried / rnid_txreq_flits_total",
> +               "ScaleUnit": "100%",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       },
> +       {
> +               "MetricName": "sbsx_actual_write_bandwidth.all",
> +               "BriefDescription": "sbsx actual write bandwidth(MB/sec).",

Nit, same thing.

Thanks,
Ian

> +               "MetricGroup": "arm_cmn",
> +               "MetricExpr": "sbsx_txdat_flitv * 32 / 1e6 / duration_time",
> +               "ScaleUnit": "1MB/s",
> +               "Unit": "arm_cmn",
> +               "Compat": "arm_cmn600;arm_cmn650;arm_cmn700;arm_ci700"
> +       }
> +]
> diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
> index 2bcd07c..7cff2c6 100755
> --- a/tools/perf/pmu-events/jevents.py
> +++ b/tools/perf/pmu-events/jevents.py
> @@ -256,6 +256,7 @@ class JsonEvent:
>            'DFPMC': 'amd_df',
>            'cpu_core': 'cpu_core',
>            'cpu_atom': 'cpu_atom',
> +          'arm_cmn': 'arm_cmn',
>        }
>        return table[unit] if unit in table else f'uncore_{unit.lower()}'
>
> --
> 1.8.3.1
>