linux-kernel - [PATCH v3 05/35] perf pmu: Detect ARM and hybrid PMUs with sysfs

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Message-Id: <20230524221831.1741381-6-irogers@google.com>
Date:   Wed, 24 May 2023 15:18:01 -0700
From:   Ian Rogers <irogers@...gle.com>
To:     Suzuki K Poulose <suzuki.poulose@....com>,
        Mike Leach <mike.leach@...aro.org>,
        Leo Yan <leo.yan@...aro.org>,
        John Garry <john.g.garry@...cle.com>,
        Will Deacon <will@...nel.org>,
        James Clark <james.clark@....com>,
        Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Jiri Olsa <jolsa@...nel.org>,
        Namhyung Kim <namhyung@...nel.org>,
        Ian Rogers <irogers@...gle.com>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Kajol Jain <kjain@...ux.ibm.com>,
        Jing Zhang <renyu.zj@...ux.alibaba.com>,
        Kan Liang <kan.liang@...ux.intel.com>,
        Zhengjun Xing <zhengjun.xing@...ux.intel.com>,
        Ravi Bangoria <ravi.bangoria@....com>,
        Madhavan Srinivasan <maddy@...ux.ibm.com>,
        Athira Rajeev <atrajeev@...ux.vnet.ibm.com>,
        Ming Wang <wangming01@...ngson.cn>,
        Huacai Chen <chenhuacai@...nel.org>,
        Sandipan Das <sandipan.das@....com>,
        Dmitrii Dolgov <9erthalion6@...il.com>,
        Sean Christopherson <seanjc@...gle.com>,
        Ali Saidi <alisaidi@...zon.com>, Rob Herring <robh@...nel.org>,
        Thomas Richter <tmricht@...ux.ibm.com>,
        Kang Minchul <tegongkang@...il.com>,
        linux-kernel@...r.kernel.org, coresight@...ts.linaro.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-perf-users@...r.kernel.org
Subject: [PATCH v3 05/35] perf pmu: Detect ARM and hybrid PMUs with sysfs

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@...gle.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 f4f0afbc391c..7392cec725bf 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -643,12 +643,14 @@ 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];
 
@@ -814,7 +816,7 @@ 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,
 	};
 
@@ -1647,22 +1649,27 @@ 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,
@@ -1716,7 +1723,7 @@ 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 0e0cb6283594..f50919f1b34c 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