[PATCH v3 7/7] docs: perf: Update metric usage for Alibaba's T-Head PMU driver

[Ian Rogers]

On Tue, May 30, 2023 at 2:19 AM Jing Zhang <renyu.zj at linux.alibaba.com> wrote:
>
> Alibaba's T-Head ali_drw PMU supports DDR bandwidth metrics. Update
> its usage in the documentation.
>
> Signed-off-by: Jing Zhang <renyu.zj at linux.alibaba.com>

Acked-by: Ian Rogers <irogers at google.com>

Thanks,
Ian

> ---
>  Documentation/admin-guide/perf/alibaba_pmu.rst | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/Documentation/admin-guide/perf/alibaba_pmu.rst b/Documentation/admin-guide/perf/alibaba_pmu.rst
> index 11de998..7d84002 100644
> --- a/Documentation/admin-guide/perf/alibaba_pmu.rst
> +++ b/Documentation/admin-guide/perf/alibaba_pmu.rst
> @@ -88,6 +88,11 @@ data bandwidth::
>      -e ali_drw_27080/hif_rmw/ \
>      -e ali_drw_27080/cycle/ -- sleep 10
>
> +Example usage of counting all memory read/write bandwidth by metric::
> +
> +  perf stat -M ddr_read_bandwidth.all -- sleep 10
> +  perf stat -M ddr_write_bandwidth.all -- sleep 10
> +
>  The average DRAM bandwidth can be calculated as follows:
>
>  - Read Bandwidth =  perf_hif_rd * DDRC_WIDTH * DDRC_Freq / DDRC_Cycle
> --
> 1.8.3.1
>