1 files changed, 27 insertions, 15 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index d264c143b592..5df59812b80c 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -3562,7 +3562,7 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err,
 
 		/* If event has exclude user then don't exclude kernel. */
 		if (evsel->core.attr.exclude_user)
-			return false;
+			goto no_fallback;
 
 		/* Is there already the separator in the name. */
 		if (strchr(name, '/') ||
@@ -3570,7 +3570,7 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err,
 			sep = "";
 
 		if (asprintf(&new_name, "%s%su", name, sep) < 0)
-			return false;
+			goto no_fallback;
 
 		free(evsel->name);
 		evsel->name = new_name;
@@ -3593,17 +3593,19 @@ bool evsel__fallback(struct evsel *evsel, struct target *target, int err,
 			sep = "";
 
 		if (asprintf(&new_name, "%s%sH", name, sep) < 0)
-			return false;
+			goto no_fallback;
 
 		free(evsel->name);
 		evsel->name = new_name;
 		/* Apple M1 requires exclude_guest */
-		scnprintf(msg, msgsize, "trying to fall back to excluding guest samples");
+		scnprintf(msg, msgsize, "Trying to fall back to excluding guest samples");
 		evsel->core.attr.exclude_guest = 1;
 
 		return true;
 	}
-
+no_fallback:
+	scnprintf(msg, msgsize, "No fallback found for '%s' for error %d",
+		  evsel__name(evsel), err);
 	return false;
 }
 
@@ -3935,6 +3937,8 @@ bool evsel__is_hybrid(const struct evsel *evsel)
 
 struct evsel *evsel__leader(const struct evsel *evsel)
 {
+	if (evsel->core.leader == NULL)
+		return NULL;
 	return container_of(evsel->core.leader, struct evsel, core);
 }
 
@@ -4048,9 +4052,9 @@ bool evsel__set_needs_uniquify(struct evsel *counter, const struct perf_stat_con
 
 void evsel__uniquify_counter(struct evsel *counter)
 {
-	const char *name, *pmu_name;
-	char *new_name, *config;
-	int ret;
+	const char *name, *pmu_name, *config;
+	char *new_name;
+	int len, ret;
 
 	/* No uniquification necessary. */
 	if (!counter->needs_uniquify)
@@ -4064,15 +4068,23 @@ void evsel__uniquify_counter(struct evsel *counter)
 	counter->uniquified_name = true;
 
 	name = evsel__name(counter);
+	config = strchr(name, '/');
 	pmu_name = counter->pmu->name;
-	/* Already prefixed by the PMU name. */
-	if (!strncmp(name, pmu_name, strlen(pmu_name)))
-		return;
 
-	config = strchr(name, '/');
-	if (config) {
-		int len = config - name;
+	/* Already prefixed by the PMU name? */
+	len = pmu_name_len_no_suffix(pmu_name);
+
+	if (!strncmp(name, pmu_name, len)) {
+		/*
+		 * If the PMU name is there, then there is no sense in not
+		 * having a slash. Do this for robustness.
+		 */
+		if (config == NULL)
+			config = name - 1;
 
+		ret = asprintf(&new_name, "%s/%s", pmu_name, config + 1);
+	} else if (config) {
+		len = config - name;
 		if (config[1] == '/') {
 			/* case: event// */
 			ret = asprintf(&new_name, "%s/%.*s/%s", pmu_name, len, name, config + 2);
@@ -4084,7 +4096,7 @@ void evsel__uniquify_counter(struct evsel *counter)
 		config = strchr(name, ':');
 		if (config) {
 			/* case: event:.. */
-			int len = config - name;
+			len = config - name;
 
 			ret = asprintf(&new_name, "%s/%.*s/%s", pmu_name, len, name, config + 1);
 		} else {