[PATCH 2/2] perf list: Add usage

[David Ahern <dsahern@gmail.com>]

Currently perf list is not very helpful if you forget the syntax:
  $ perf list -h

  List of pre-defined events (to be used in -e):

After:
  $ perf list -h

   usage: perf list [hw|sw|cache|tracepoint|pmu|event_glob]

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
---
 tools/perf/builtin-list.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tools/perf/builtin-list.c b/tools/perf/builtin-list.c
index 45000e7d4398..a5ad93206044 100644
--- a/tools/perf/builtin-list.c
+++ b/tools/perf/builtin-list.c
@@ -14,10 +14,21 @@
 #include "util/parse-events.h"
 #include "util/cache.h"
 #include "util/pmu.h"
+#include "util/parse-options.h"
 
 int cmd_list(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	int i;
+	const struct option list_options[] = {
+		OPT_END()
+	};
+	const char * const list_usage[] = {
+		"perf list [hw|sw|cache|tracepoint|pmu|event_glob]",
+		NULL
+	};
+
+	argc = parse_options(argc, argv, list_options, list_usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
 
 	setup_pager();
 
-- 
1.8.3.4 (Apple Git-47)