Re: [PATCH 5/9] perf stat: Fix --metric-only --json output

From: Arnaldo Carvalho de Melo
Date: Tue Nov 08 2022 - 15:46:16 EST


Em Mon, Nov 07, 2022 at 01:33:10PM -0800, Namhyung Kim escreveu:
> Currently it prints all metric headers for JSON output. But actually it
> skips some metrics with valid_only_metric(). So the output looks like:
>
> $ perf stat --metric-only --json true
> {"unit" : "CPUs utilized", "unit" : "/sec", "unit" : "/sec", "unit" : "/sec", "unit" : "GHz", "unit" : "insn per cycle", "unit" : "/sec", "unit" : "branch-misses of all branches"}
> {"metric-value" : "3.861"}{"metric-value" : "0.79"}{"metric-value" : "3.04"}
>
> As you can see there are 8 units in the header but only 3 metric-values
> are there. It should skip the unused headers as well. Also each unit
> should be printed as a separate object like metric values.
>
> With this patch:
>
> $ perf stat --metric-only --json true
> {"unit" : "GHz"}{"unit" : "insn per cycle"}{"unit" : "branch-misses of all branches"}
> {"metric-value" : "4.166"}{"metric-value" : "0.73"}{"metric-value" : "2.96"}

Can we get a Fixes tag for this one?

- Arnaldo

> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> tools/perf/util/stat-display.c | 22 +++-------------------
> 1 file changed, 3 insertions(+), 19 deletions(-)
>
> diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
> index 115477461224..515fb6db3d67 100644
> --- a/tools/perf/util/stat-display.c
> +++ b/tools/perf/util/stat-display.c
> @@ -430,12 +430,12 @@ static void print_metric_header(struct perf_stat_config *config,
> os->evsel->priv != os->evsel->evlist->selected->priv)
> return;
>
> - if (!valid_only_metric(unit) && !config->json_output)
> + if (!valid_only_metric(unit))
> return;
> unit = fixunit(tbuf, os->evsel, unit);
>
> if (config->json_output)
> - fprintf(os->fh, "\"unit\" : \"%s\"", unit);
> + fprintf(os->fh, "{\"unit\" : \"%s\"}", unit);
> else if (config->csv_output)
> fprintf(os->fh, "%s%s", unit, config->csv_sep);
> else
> @@ -847,10 +847,6 @@ static void print_metric_headers(struct perf_stat_config *config,
> .new_line = new_line_metric,
> .force_header = true,
> };
> - bool first = true;
> -
> - if (config->json_output && !config->interval)
> - fprintf(config->output, "{");
>
> if (prefix && !config->json_output)
> fprintf(config->output, "%s", prefix);
> @@ -871,18 +867,12 @@ static void print_metric_headers(struct perf_stat_config *config,
> evlist__for_each_entry(evlist, counter) {
> os.evsel = counter;
>
> - if (!first && config->json_output)
> - fprintf(config->output, ", ");
> - first = false;
> -
> perf_stat__print_shadow_stats(config, counter, 0,
> 0,
> &out,
> &config->metric_events,
> &rt_stat);
> }
> - if (config->json_output)
> - fprintf(config->output, "}");
> fputc('\n', config->output);
> }
>
> @@ -954,14 +944,8 @@ static void print_interval(struct perf_stat_config *config,
> }
> }
>
> - if ((num_print_interval == 0 || config->interval_clear)
> - && metric_only && !config->json_output)
> + if ((num_print_interval == 0 || config->interval_clear) && metric_only)
> print_metric_headers(config, evlist, " ", true);
> - if ((num_print_interval == 0 || config->interval_clear)
> - && metric_only && config->json_output) {
> - fprintf(output, "{");
> - print_metric_headers(config, evlist, " ", true);
> - }
> if (++num_print_interval == 25)
> num_print_interval = 0;
> }
> --
> 2.38.1.431.g37b22c650d-goog

--

- Arnaldo