From: Ian Rogers <irogers@google.com>
Date: Sun, 5 Oct 2025 18:24:22 +0000 (-0700)
Subject: perf evlist: Avoid scanning all PMUs for evlist__new_default
X-Git-Tag: v6.19-rc1~61^2~191
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5bf6291113d2aaa559455a04ecc2c5e6396d05a0;p=thirdparty%2Fkernel%2Flinux.git

perf evlist: Avoid scanning all PMUs for evlist__new_default

Rather than wildcard matching the cycles event specify only the core
PMUs. This avoids potentially loading unnecessary uncore PMUs.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 80d8387e6b97b..e8217efdda532 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -101,16 +101,24 @@ struct evlist *evlist__new_default(void)
 {
 	struct evlist *evlist = evlist__new();
 	bool can_profile_kernel;
-	int err;
+	struct perf_pmu *pmu = NULL;
 
 	if (!evlist)
 		return NULL;
 
 	can_profile_kernel = perf_event_paranoid_check(1);
-	err = parse_event(evlist, can_profile_kernel ? "cycles:P" : "cycles:Pu");
-	if (err) {
-		evlist__delete(evlist);
-		return NULL;
+
+	while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
+		char buf[256];
+		int err;
+
+		snprintf(buf, sizeof(buf), "%s/cycles/%s", pmu->name,
+			 can_profile_kernel ? "P" : "Pu");
+		err = parse_event(evlist, buf);
+		if (err) {
+			evlist__delete(evlist);
+			return NULL;
+		}
 	}
 
 	if (evlist->core.nr_entries > 1) {