Re: [PATCH] perf test: Retry without grouping for all metrics test

[Ayush Jain]

Hello Sandipan,

Thank you for this patch,

On 6/14/2023 2:37 PM, Sandipan Das wrote:
> There are cases where a metric uses more events than the number of
> counters. E.g. AMD Zen, Zen 2 and Zen 3 processors have four data fabric
> counters but the "nps1_die_to_dram" metric has eight events. By default,
> the constituent events are placed in a group. Since the events cannot be
> scheduled at the same time, the metric is not computed. The all metrics
> test also fails because of this.
>
> Before announcing failure, the test can try multiple options for each
> available metric. After system-wide mode fails, retry once again with
> the "--metric-no-group" option.
>
> E.g.
>
>    $ sudo perf test -v 100
>
> Before:
>
>    100: perf all metrics test                                           :
>    --- start ---
>    test child forked, pid 672731
>    Testing branch_misprediction_ratio
>    Testing all_remote_links_outbound
>    Testing nps1_die_to_dram
>    Metric 'nps1_die_to_dram' not printed in:
>    Error:
>    Invalid event (dram_channel_data_controller_4) in per-thread mode, enable system wide with '-a'.
>    Testing macro_ops_dispatched
>    Testing all_l2_cache_accesses
>    Testing all_l2_cache_hits
>    Testing all_l2_cache_misses
>    Testing ic_fetch_miss_ratio
>    Testing l2_cache_accesses_from_l2_hwpf
>    Testing l2_cache_misses_from_l2_hwpf
>    Testing op_cache_fetch_miss_ratio
>    Testing l3_read_miss_latency
>    Testing l1_itlb_misses
>    test child finished with -1
>    ---- end ----
>    perf all metrics test: FAILED!
>
> After:
>
>    100: perf all metrics test                                           :
>    --- start ---
>    test child forked, pid 672887
>    Testing branch_misprediction_ratio
>    Testing all_remote_links_outbound
>    Testing nps1_die_to_dram
>    Testing macro_ops_dispatched
>    Testing all_l2_cache_accesses
>    Testing all_l2_cache_hits
>    Testing all_l2_cache_misses
>    Testing ic_fetch_miss_ratio
>    Testing l2_cache_accesses_from_l2_hwpf
>    Testing l2_cache_misses_from_l2_hwpf
>    Testing op_cache_fetch_miss_ratio
>    Testing l3_read_miss_latency
>    Testing l1_itlb_misses
>    test child finished with 0
>    ---- end ----
>    perf all metrics test: Ok

Issue gets resolved after applying this patch

  $ ./perf test 102 -vvv
  $102: perf all metrics test                                           :
  $--- start ---
  $test child forked, pid 244991
  $Testing branch_misprediction_ratio
  $Testing all_remote_links_outbound
  $Testing nps1_die_to_dram
  $Testing all_l2_cache_accesses
  $Testing all_l2_cache_hits
  $Testing all_l2_cache_misses
  $Testing ic_fetch_miss_ratio
  $Testing l2_cache_accesses_from_l2_hwpf
  $Testing l2_cache_misses_from_l2_hwpf
  $Testing l3_read_miss_latency
  $Testing l1_itlb_misses
  $test child finished with 0
  $---- end ----
  $perf all metrics test: Ok

> Reported-by: Ayush Jain <ayush.jain3@xxxxxxx>
> Signed-off-by: Sandipan Das <sandipan.das@xxxxxxx>

Tested-by: Ayush Jain <ayush.jain3@xxxxxxx>

> ---
>   tools/perf/tests/shell/stat_all_metrics.sh | 7 +++++++
>   1 file changed, 7 insertions(+)
>
> diff --git a/tools/perf/tests/shell/stat_all_metrics.sh b/tools/perf/tests/shell/stat_all_metrics.sh
> index 54774525e18a..1e88ea8c5677 100755
> --- a/tools/perf/tests/shell/stat_all_metrics.sh
> +++ b/tools/perf/tests/shell/stat_all_metrics.sh
> @@ -16,6 +16,13 @@ for m in $(perf list --raw-dump metrics); do
>     then
>       continue
>     fi
> +  # Failed again, possibly there are not enough counters so retry system wide
> +  # mode but without event grouping.
> +  result=$(perf stat -M "$m" --metric-no-group -a sleep 0.01 2>&1)
> +  if [[ "$result" =~ ${m:0:50} ]]
> +  then
> +    continue
> +  fi
>     # Failed again, possibly the workload was too small so retry with something
>     # longer.
>     result=$(perf stat -M "$m" perf bench internals synthesize 2>&1)

Thanks & Regards,
Ayush Jain