perf list: Show error if tracepoints not available

Tracepoints are not visible in "perf list" on Fedora 19 because regular users have no permission to /sys/kernel/debug by default. Show an error message so that the user knows about it instead of assuming that tracepoints are not supported on the system. Signed-off-by: Pekka Enberg <[email protected]> Acked-by: Ingo Molnar <[email protected]> Cc: Ingo Molnar <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
TechNexion · Oct 21, 2013 · f11cfc6 · f11cfc6
1 parent 243be3d
commit f11cfc6
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
@@ -998,8 +998,10 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob,
 	char evt_path[MAXPATHLEN];
 	char dir_path[MAXPATHLEN];
 
-	if (debugfs_valid_mountpoint(tracing_events_path))
+	if (debugfs_valid_mountpoint(tracing_events_path)) {
+		printf("  [ Tracepoints not available: %s ]\n", strerror(errno));
 		return;
+	}
 
 	sys_dir = opendir(tracing_events_path);
 	if (!sys_dir)