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perf stat: Use counter cpumask to skip zero values

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When a counter is 0 it may or may not be skipped.

For uncore counters it is common they are only valid on 1 logical CPU
and all other CPUs should be skipped.

The PMU's cpumask was used for the skip calculation, but that cpumask
may not reflect user overrides.

Similarly a counter on a core PMU may explicitly not request a CPU be
gathered.

If the counter on this CPU's value is 0 then the counter should be
skipped as it wasn't requested.

Switch from using the PMU cpumask to that associated with the evsel to
support these cases.

Avoid potential crash with --per-thread mode where config->aggr_get_id
is NULL. Add some examples for the tool event 0 counter skipping.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20250403194337.40202-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ian Rogers 2025-04-03 12:43:35 -07:00 committed by Arnaldo Carvalho de Melo
parent 2e7a2f7f3c
commit f60c3f4468
1 changed files with 13 additions and 8 deletions
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21
tools/perf/util/stat-display.c
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@ -1008,8 +1008,16 @@ static bool should_skip_zero_counter(struct perf_stat_config *config,
return true;
/*
* Many tool events are only gathered on the first index, skip other
* zero values.
* In per-thread mode the aggr_map and aggr_get_id functions may be
* NULL, assume all 0 values should be output in that case.
*/
if (!config->aggr_map || !config->aggr_get_id)
return false;
/*
* Tool events may be gathered on all logical CPUs, for example
* system_time, but for many the first index is the only one used, for
* example num_cores. Don't skip for the first index.
*/
if (evsel__is_tool(counter)) {
struct aggr_cpu_id own_id =
@ -1017,15 +1025,12 @@ static bool should_skip_zero_counter(struct perf_stat_config *config,
return !aggr_cpu_id__equal(id, &own_id);
}
/*
* Skip value 0 when it's an uncore event and the given aggr id
* does not belong to the PMU cpumask.
* Skip value 0 when the counter's cpumask doesn't match the given aggr
* id.
*/
if (!counter->pmu || !counter->pmu->is_uncore)
return false;
perf_cpu_map__for_each_cpu(cpu, idx, counter->pmu->cpus) {
perf_cpu_map__for_each_cpu(cpu, idx, counter->core.cpus) {
struct aggr_cpu_id own_id = config->aggr_get_id(config, cpu);
if (aggr_cpu_id__equal(id, &own_id))