Re: [PATCH v2] perf list: For metricgroup only list include description

[Namhyung Kim <namhyung@kernel.org>]

On Fri, Feb 16, 2024 at 11:20:44AM -0800, Ian Rogers wrote:
> If perf list is invoked with 'metricgroups' include the description
> unless it is invoked with flags to exclude it. Make the description of
> metricgroup dumping dependent on the desc flag in print_state as with
> metrics.
> 
> Before:
> ```
> $ perf list metricgroups
> List of pre-defined events (to be used in -e or -M):
> 
> Metric Groups:
> 
> Backend
> Bad
> BadSpec
> ...
> ```
> 
> After:
> ```
> $ perf list metricgroups
> List of pre-defined events (to be used in -e or -M):
> 
> Metric Groups:
> 
> Backend [Grouping from Top-down Microarchitecture Analysis Metrics spreadsheet]
> Bad [Grouping from Top-down Microarchitecture Analysis Metrics spreadsheet]
> BadSpec
> ...
> ```

When I run `perf list` and look at the Metric Groups:

  Metric Groups:
  
  Backend: [Grouping from Top-down Microarchitecture Analysis Metrics spreadsheet]
    tma_core_bound
         [This metric represents fraction of slots where Core non-memory issues were of a bottleneck]
    tma_info_core_ilp
         [Instruction-Level-Parallelism (average number of uops executed when there is execution) per-core]
    tma_info_memory_l2mpki
         [L2 cache true misses per kilo instruction for retired demand loads]
    tma_memory_bound
         [This metric represents fraction of slots the Memory subsystem within the Backend was a bottleneck]
  
  Bad: [Grouping from Top-down Microarchitecture Analysis Metrics spreadsheet]
    tma_info_bad_spec_branch_misprediction_cost
         [Branch Misprediction Cost: Fraction of TMA slots wasted per non-speculative branch misprediction (retired JEClear)]
    tma_info_bad_spec_ipmisp_cond_ntaken
         [Instructions per retired mispredicts for conditional non-taken branches (lower number means higher occurrence rate)]
    tma_info_bad_spec_ipmisp_cond_taken
         [Instructions per retired mispredicts for conditional taken branches (lower number means higher occurrence rate)]
    ...
 
So this change aligns with the default behavior, so

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
> v2 rebases on top of perf-tools-next patch:
> 79bacb6ad73c perf list: Add output file option
> https://lore.kernel.org/r/20240124043015.1388867-3-irogers@google.com
> ---
>  tools/perf/builtin-list.c | 21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/perf/builtin-list.c b/tools/perf/builtin-list.c
> index e27a1b1288c2..02bf608d585e 100644
> --- a/tools/perf/builtin-list.c
> +++ b/tools/perf/builtin-list.c
> @@ -208,17 +208,24 @@ static void default_print_metric(void *ps,
>  	if (!print_state->last_metricgroups ||
>  	    strcmp(print_state->last_metricgroups, group ?: "")) {
>  		if (group && print_state->metricgroups) {
> -			if (print_state->name_only)
> +			if (print_state->name_only) {
>  				fprintf(fp, "%s ", group);
> -			else if (print_state->metrics) {
> -				const char *gdesc = describe_metricgroup(group);
> +			} else {
> +				const char *gdesc = print_state->desc
> +					? describe_metricgroup(group)
> +					: NULL;
> +				const char *print_colon = "";
> +
> +				if (print_state->metrics) {
> +					print_colon = ":";
> +					fputc('\n', fp);
> +				}
>  
>  				if (gdesc)
> -					fprintf(fp, "\n%s: [%s]\n", group, gdesc);
> +					fprintf(fp, "%s%s [%s]\n", group, print_colon, gdesc);
>  				else
> -					fprintf(fp, "\n%s:\n", group);
> -			} else
> -				fprintf(fp, "%s\n", group);
> +					fprintf(fp, "%s%s\n", group, print_colon);
> +			}
>  		}
>  		zfree(&print_state->last_metricgroups);
>  		print_state->last_metricgroups = strdup(group ?: "");
> -- 
> 2.44.0.rc0.258.g7320e95886-goog
>