1 files changed, 24 insertions, 18 deletions

diff --git a/tools/perf/util/print-events.c b/tools/perf/util/print-events.c
index b0fc48be623f..7b54e9385442 100644
--- a/tools/perf/util/print-events.c
+++ b/tools/perf/util/print-events.c
@@ -28,6 +28,7 @@
 #include "tracepoint.h"
 #include "pfm.h"
 #include "thread_map.h"
+#include "util.h"
 
 #define MAX_NAME_LEN 100
 
@@ -63,17 +64,16 @@ void print_tracepoint_events(const struct print_callbacks *print_cb __maybe_unus
 {
 	char *events_path = get_tracing_file("events");
 	int events_fd = open(events_path, O_PATH);
+	struct dirent **sys_namelist = NULL;
+	int sys_items;
 
 	put_tracing_file(events_path);
 	if (events_fd < 0) {
-		printf("Error: failed to open tracing events directory\n");
+		pr_err("Error: failed to open tracing events directory\n");
 		return;
 	}
 
-#ifdef HAVE_SCANDIRAT_SUPPORT
-{
-	struct dirent **sys_namelist = NULL;
-	int sys_items = tracing_events__scandir_alphasort(&sys_namelist);
+	sys_items = tracing_events__scandir_alphasort(&sys_namelist);
 
 	for (int i = 0; i < sys_items; i++) {
 		struct dirent *sys_dirent = sys_namelist[i];
@@ -130,11 +130,6 @@ next_sys:
 	}
 
 	free(sys_namelist);
-}
-#else
-	printf("\nWARNING: Your libc doesn't have the scandirat function, please ask its maintainers to implement it.\n"
-	       "         As a rough fallback, please do 'ls %s' to see the available tracepoint events.\n", events_path);
-#endif
 	close(events_fd);
 }
 
@@ -232,7 +227,6 @@ void print_sdt_events(const struct print_callbacks *print_cb, void *print_state)
 bool is_event_supported(u8 type, u64 config)
 {
 	bool ret = true;
-	int open_return;
 	struct evsel *evsel;
 	struct perf_event_attr attr = {
 		.type = type,
@@ -246,20 +240,32 @@ bool is_event_supported(u8 type, u64 config)
 
 	evsel = evsel__new(&attr);
 	if (evsel) {
-		open_return = evsel__open(evsel, NULL, tmap);
-		ret = open_return >= 0;
+		ret = evsel__open(evsel, NULL, tmap) >= 0;
 
-		if (open_return == -EACCES) {
+		if (!ret) {
 			/*
-			 * This happens if the paranoid value
+			 * The event may fail to open if the paranoid value
 			 * /proc/sys/kernel/perf_event_paranoid is set to 2
-			 * Re-run with exclude_kernel set; we don't do that
-			 * by default as some ARM machines do not support it.
-			 *
+			 * Re-run with exclude_kernel set; we don't do that by
+			 * default as some ARM machines do not support it.
 			 */
 			evsel->core.attr.exclude_kernel = 1;
 			ret = evsel__open(evsel, NULL, tmap) >= 0;
 		}
+
+		if (!ret) {
+			/*
+			 * The event may fail to open if the PMU requires
+			 * exclude_guest to be set (e.g. as the Apple M1 PMU
+			 * requires).
+			 * Re-run with exclude_guest set; we don't do that by
+			 * default as it's equally legitimate for another PMU
+			 * driver to require that exclude_guest is clear.
+			 */
+			evsel->core.attr.exclude_guest = 1;
+			ret = evsel__open(evsel, NULL, tmap) >= 0;
+		}
+
 		evsel__delete(evsel);
 	}