perf evsel: Reduce scanning core PMUs in is_hybrid

captain5050 · namhyung · commit 340c345e587e · 2025-02-04T21:28:25.000-08:00
evsel__is_hybrid returns true if there are multiple core PMUs and the evsel is for a core PMU. Determining the number of core PMUs can require loading/scanning PMUs. There's no point doing the scanning if evsel for the is_hybrid test isn't core so reorder the tests to reduce PMU scanning. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20250201074320.746259-2-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
@@ -3866,10 +3866,10 @@ void evsel__zero_per_pkg(struct evsel *evsel)
  */
 bool evsel__is_hybrid(const struct evsel *evsel)
 {
-	if (perf_pmus__num_core_pmus() == 1)
+	if (!evsel->core.is_pmu_core)
 		return false;
 
-	return evsel->core.is_pmu_core;
+	return perf_pmus__num_core_pmus() > 1;
 }
 
 struct evsel *evsel__leader(const struct evsel *evsel)

Original file line number	Diff line number	Diff line change
`@@ -3866,10 +3866,10 @@ void evsel__zero_per_pkg(struct evsel *evsel)`
`3866`	`3866`	`*/`
`3867`	`3867`	`bool evsel__is_hybrid(const struct evsel *evsel)`
`3868`	`3868`	`{`
`3869`		`- if (perf_pmus__num_core_pmus() == 1)`
	`3869`	`+ if (!evsel->core.is_pmu_core)`
`3870`	`3870`	`return false;`
`3871`	`3871`
`3872`		`- return evsel->core.is_pmu_core;`
	`3872`	`+ return perf_pmus__num_core_pmus() > 1;`
`3873`	`3873`	`}`
`3874`	`3874`
`3875`	`3875`	`struct evsel evsel__leader(const struct evsel evsel)`