From ab1a1c77a38ad1efea4396f271ccde53b58c1b8e Mon Sep 17 00:00:00 2001
From: Ian Rogers <irogers@google.com>
Date: Sat, 27 May 2023 00:21:52 -0700
Subject: [PATCH] perf pmu: Rewrite perf_pmu__has_hybrid to avoid list

Rather than list empty on perf_pmu__hybrid_pmus, detect if any core
PMUs match the hybrid name. Computed values held in statics to avoid
recomputation.

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ali Saidi <alisaidi@amazon.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kang Minchul <tegongkang@gmail.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230527072210.2900565-17-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/pmu.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 83c7eeb..5a7bfbf 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -60,8 +60,6 @@ struct perf_pmu_format {
 	struct list_head list;
 };
 
-static bool hybrid_scanned;
-
 static struct perf_pmu *perf_pmu__find2(int dirfd, const char *name);
 
 /*
@@ -2013,12 +2011,20 @@ void perf_pmu__warn_invalid_config(struct perf_pmu *pmu, __u64 config,
 
 bool perf_pmu__has_hybrid(void)
 {
+	static bool hybrid_scanned, has_hybrid;
+
 	if (!hybrid_scanned) {
+		struct perf_pmu *pmu = NULL;
+
+		while ((pmu = perf_pmu__scan(pmu)) != NULL) {
+			if (pmu->is_core && is_pmu_hybrid(pmu->name)) {
+				has_hybrid = true;
+				break;
+			}
+		}
 		hybrid_scanned = true;
-		perf_pmu__scan(NULL);
 	}
-
-	return !list_empty(&perf_pmu__hybrid_pmus);
+	return has_hybrid;
 }
 
 int perf_pmu__match(char *pattern, char *name, char *tok)
-- 
2.7.4