linux-kernel - [PATCH v5 15/34] perf pmu: Remove perf_pmu__hybrid

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Message-Id: <20230527072210.2900565-16-irogers@google.com>
Date:   Sat, 27 May 2023 00:21:51 -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 v5 15/34] perf pmu: Remove perf_pmu__hybrid_mounted

perf_pmu__hybrid_mounted is used to detect whether cpu_core or
cpu_atom is mounted with a non-empty cpus file by
pmu_lookup. Discussion [1] showed the empty cpus file check to be
redundant and so pmu_lookup needn't have a call to
perf_pmu__hybrid_mounted.

Checking hybrid_mounted in pmu_is_uncore is redundant as the next
cpumask read will fail returning false.

Reduce the scope of perf_pmu__find_hybrid_pmu by making it static.

[1] https://lore.kernel.org/lkml/20230524221831.1741381-17-irogers@google.com/

Signed-off-by: Ian Rogers <irogers@...gle.com>
Reviewed-by: Kan Liang <kan.liang@...ux.intel.com>
---
 tools/perf/util/pmu-hybrid.c | 15 +--------------
 tools/perf/util/pmu-hybrid.h |  3 ---
 tools/perf/util/pmu.c        | 13 +------------
 3 files changed, 2 insertions(+), 29 deletions(-)

diff --git a/tools/perf/util/pmu-hybrid.c b/tools/perf/util/pmu-hybrid.c
index bc4cb0738c35..7fe943dd3217 100644
--- a/tools/perf/util/pmu-hybrid.c
+++ b/tools/perf/util/pmu-hybrid.c
@@ -18,20 +18,7 @@
 
 LIST_HEAD(perf_pmu__hybrid_pmus);
 
-bool perf_pmu__hybrid_mounted(const char *name)
-{
-	int cpu;
-	char pmu_name[PATH_MAX];
-	struct perf_pmu pmu = {.name = pmu_name};
-
-	if (strncmp(name, "cpu_", 4))
-		return false;
-
-	strlcpy(pmu_name, name, sizeof(pmu_name));
-	return perf_pmu__scan_file(&pmu, "cpus", "%u", &cpu) > 0;
-}
-
-struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name)
+static struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name)
 {
 	struct perf_pmu *pmu;
 
diff --git a/tools/perf/util/pmu-hybrid.h b/tools/perf/util/pmu-hybrid.h
index 206b94931531..8dbcae935020 100644
--- a/tools/perf/util/pmu-hybrid.h
+++ b/tools/perf/util/pmu-hybrid.h
@@ -13,9 +13,6 @@ extern struct list_head perf_pmu__hybrid_pmus;
 #define perf_pmu__for_each_hybrid_pmu(pmu)	\
 	list_for_each_entry(pmu, &perf_pmu__hybrid_pmus, hybrid_list)
 
-bool perf_pmu__hybrid_mounted(const char *name);
-
-struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name);
 bool perf_pmu__is_hybrid(const char *name);
 
 static inline int perf_pmu__hybrid_pmu_num(void)
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index cd94abe7a87a..83c7eeb8abea 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -617,9 +617,6 @@ static bool pmu_is_uncore(int dirfd, const char *name)
 {
 	int fd;
 
-	if (perf_pmu__hybrid_mounted(name))
-		return false;
-
 	fd = perf_pmu__pathname_fd(dirfd, name, "cpumask", O_PATH);
 	if (fd < 0)
 		return false;
@@ -907,15 +904,8 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)
 	LIST_HEAD(aliases);
 	__u32 type;
 	char *name = pmu_find_real_name(lookup_name);
-	bool is_hybrid = perf_pmu__hybrid_mounted(name);
 	char *alias_name;
 
-	/*
-	 * Check pmu name for hybrid and the pmu may be invalid in sysfs
-	 */
-	if (!strncmp(name, "cpu_", 4) && !is_hybrid)
-		return NULL;
-
 	/*
 	 * The pmu data we store & need consists of the pmu
 	 * type value and format definitions. Load both right
@@ -936,7 +926,6 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)
 
 	pmu->cpus = pmu_cpumask(dirfd, name);
 	pmu->name = strdup(name);
-
 	if (!pmu->name)
 		goto err;
 
@@ -967,7 +956,7 @@ static struct perf_pmu *pmu_lookup(int dirfd, const char *lookup_name)
 	list_splice(&aliases, &pmu->aliases);
 	list_add_tail(&pmu->list, &pmus);
 
-	if (is_hybrid)
+	if (!strcmp(name, "cpu_core") || !strcmp(name, "cpu_atom"))
 		list_add_tail(&pmu->hybrid_list, &perf_pmu__hybrid_pmus);
 	else
 		INIT_LIST_HEAD(&pmu->hybrid_list);
-- 
2.41.0.rc0.172.g3f132b7071-goog