perf test parse-events: Test complex name has required event format

test__checkevent_complex_name will use an "event" format which if not
present, such as with a placeholder PMU, will cause test failures. Skip
the test in this case to avoid failures in restricted environments.

Add perf_pmu__has_format utility as a general PMU utility.

Fixes: 628eaa4 ("perf pmus: Add placeholder core PMU")
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
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>
Link: https://lore.kernel.org/r/20230706183705.601412-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: captain5050

tools/perf/tests/parse-events.c

@@ -1631,6 +1631,16 @@ static bool test__pmu_cpu_valid(void)
 	return !!perf_pmus__find("cpu");
 }
 
+static bool test__pmu_cpu_event_valid(void)
+{
+	struct perf_pmu *pmu = perf_pmus__find("cpu");
+
+	if (!pmu)
+		return false;
+
+	return perf_pmu__has_format(pmu, "event");
+}
+
 static bool test__intel_pt_valid(void)
 {
 	return !!perf_pmus__find("intel_pt");
@@ -2179,7 +2189,7 @@ static const struct evlist_test test__events_pmu[] = {
 	},
 	{
 		.name  = "cpu/name='COMPLEX_CYCLES_NAME:orig=cycles,desc=chip-clock-ticks',period=0x1,event=0x2/ukp",
-		.valid = test__pmu_cpu_valid,
+		.valid = test__pmu_cpu_event_valid,
 		.check = test__checkevent_complex_name,
 		/* 3 */
 	},

tools/perf/util/pmu.c

@@ -1440,6 +1440,17 @@ void perf_pmu__del_formats(struct list_head *formats)
 	}
 }
 
+bool perf_pmu__has_format(const struct perf_pmu *pmu, const char *name)
+{
+	struct perf_pmu_format *format;
+
+	list_for_each_entry(format, &pmu->format, list) {
+		if (!strcmp(format->name, name))
+			return true;
+	}
+	return false;
+}
+
 bool is_pmu_core(const char *name)
 {
 	return !strcmp(name, "cpu") || !strcmp(name, "cpum_cf") || is_sysfs_pmu_core(name);

tools/perf/util/pmu.h

@@ -234,6 +234,7 @@ int perf_pmu__new_format(struct list_head *list, char *name,
 void perf_pmu__set_format(unsigned long *bits, long from, long to);
 int perf_pmu__format_parse(int dirfd, struct list_head *head);
 void perf_pmu__del_formats(struct list_head *formats);
+bool perf_pmu__has_format(const struct perf_pmu *pmu, const char *name);
 
 bool is_pmu_core(const char *name);
 bool perf_pmu__supports_legacy_cache(const struct perf_pmu *pmu);