[PATCH v2 06/23] perf pmu: Detect ARM and hybrid PMUs with sysfs

Ian Rogers irogers at google.com
Sun May 21 23:43:13 PDT 2023


is_arm_pmu_core detects a core PMU via the presence of a "cpus" file
rather than a "cpumask" file. This pattern holds for hybrid PMUs so
rename the function and remove redundant perf_pmu__is_hybrid
tests.

Add a new helper is_pmu_hybrid similar to is_pmu_core.

Signed-off-by: Ian Rogers <irogers at google.com>
---
 tools/perf/util/pmu.c | 29 ++++++++++++++++++-----------
 tools/perf/util/pmu.h |  1 +
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 729b1f166f80..0fa451c60c77 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -640,12 +640,14 @@ static char *pmu_id(const char *name)
 	return str;
 }
 
-/*
- *  PMU CORE devices have different name other than cpu in sysfs on some
- *  platforms.
- *  Looking for possible sysfs files to identify the arm core device.
+/**
+ * is_sysfs_pmu_core() - PMU CORE devices have different name other than cpu in
+ *         sysfs on some platforms like ARM or Intel hybrid. Looking for
+ *         possible the cpus file in sysfs files to identify whether this is a
+ *         core device.
+ * @name: The PMU name such as "cpu_atom".
  */
-static int is_arm_pmu_core(const char *name)
+static int is_sysfs_pmu_core(const char *name)
 {
 	char path[PATH_MAX];
 
@@ -811,7 +813,7 @@ void pmu_add_cpu_aliases_table(struct list_head *head, struct perf_pmu *pmu,
 	struct pmu_add_cpu_aliases_map_data data = {
 		.head = head,
 		.name = pmu->name,
-		.cpu_name = is_arm_pmu_core(pmu->name) ? pmu->name : "cpu",
+		.cpu_name = is_sysfs_pmu_core(pmu->name) ? pmu->name : "cpu",
 		.pmu = pmu,
 	};
 
@@ -1649,22 +1651,27 @@ static int cmp_sevent(const void *a, const void *b)
 
 bool is_pmu_core(const char *name)
 {
-	return !strcmp(name, "cpu") || is_arm_pmu_core(name);
+	return !strcmp(name, "cpu") || is_sysfs_pmu_core(name);
+}
+
+bool is_pmu_hybrid(const char *name)
+{
+	return !strcmp(name, "cpu_atom") || !strcmp(name, "cpu_core");
 }
 
 bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu)
 {
-	return is_pmu_core(pmu->name) || perf_pmu__is_hybrid(pmu->name);
+	return is_pmu_core(pmu->name);
 }
 
 bool perf_pmu__supports_wildcard_numeric(const struct perf_pmu *pmu)
 {
-	return is_pmu_core(pmu->name) || perf_pmu__is_hybrid(pmu->name);
+	return is_pmu_core(pmu->name);
 }
 
 bool perf_pmu__auto_merge_stats(const struct perf_pmu *pmu)
 {
-	return !perf_pmu__is_hybrid(pmu->name);
+	return !is_pmu_hybrid(pmu->name);
 }
 
 static bool pmu_alias_is_duplicate(struct sevent *alias_a,
@@ -1718,7 +1725,7 @@ void print_pmu_events(const struct print_callbacks *print_cb, void *print_state)
 	pmu = NULL;
 	j = 0;
 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
-		bool is_cpu = is_pmu_core(pmu->name) || perf_pmu__is_hybrid(pmu->name);
+		bool is_cpu = is_pmu_core(pmu->name);
 
 		list_for_each_entry(event, &pmu->aliases, list) {
 			aliases[j].event = event;
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index 49033bb134f3..99e0273027bf 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -220,6 +220,7 @@ void perf_pmu__del_formats(struct list_head *formats);
 struct perf_pmu *perf_pmu__scan(struct perf_pmu *pmu);
 
 bool is_pmu_core(const char *name);
+bool is_pmu_hybrid(const char *name);
 bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu);
 bool perf_pmu__supports_wildcard_numeric(const struct perf_pmu *pmu);
 bool perf_pmu__auto_merge_stats(const struct perf_pmu *pmu);
-- 
2.40.1.698.g37aff9b760-goog




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