[PATCH 14/23] perf list: Add -q/--quiet option

[Namhyung Kim]

The -q/--quiet option is to suppress any message.  Sometimes users just
want to run the command and it can be used for that case.

Suggested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
 tools/perf/Documentation/perf-list.txt | 9 ++++++++-
 tools/perf/builtin-list.c              | 9 +++++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/tools/perf/Documentation/perf-list.txt b/tools/perf/Documentation/perf-list.txt
index 41857cce5e86..7964d0e9dc8a 100644
--- a/tools/perf/Documentation/perf-list.txt
+++ b/tools/perf/Documentation/perf-list.txt
@@ -8,7 +8,7 @@ perf-list - List all symbolic event types
 SYNOPSIS
 --------
 [verse]
-'perf list' [--no-desc] [--long-desc] [hw|sw|cache|tracepoint|pmu|event_glob]
+'perf list' <options> [hw|sw|cache|tracepoint|pmu|event_glob]
 
 DESCRIPTION
 -----------
@@ -24,6 +24,13 @@ Don't print descriptions.
 --long-desc::
 Print longer event descriptions.
 
+-q::
+--quiet::
+	Do not show any message.
+
+--debug::
+	Enable debugging output.
+
 
 [[EVENT_MODIFIERS]]
 EVENT MODIFIERS
diff --git a/tools/perf/builtin-list.c b/tools/perf/builtin-list.c
index 3b9d98b5feef..b53b3597ee0f 100644
--- a/tools/perf/builtin-list.c
+++ b/tools/perf/builtin-list.c
@@ -32,6 +32,7 @@ int cmd_list(int argc, const char **argv, const char *prefix __maybe_unused)
 			    "Print longer event descriptions."),
 		OPT_INCR(0, "debug", &verbose,
 			     "Enable debugging output"),
+		OPT_BOOLEAN('q', "quiet", &quiet, "Do not show any message"),
 		OPT_END()
 	};
 	const char * const list_usage[] = {
@@ -44,9 +45,12 @@ int cmd_list(int argc, const char **argv, const char *prefix __maybe_unused)
 	argc = parse_options(argc, argv, list_options, list_usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
+	if (quiet)
+		perf_quiet_option();
+
 	setup_pager();
 
-	if (!raw_dump && pager_in_use())
+	if (!raw_dump && pager_in_use() && !quiet)
 		printf("\nList of pre-defined events (to be used in -e):\n\n");
 
 	if (argc == 0) {
@@ -94,7 +98,8 @@ int cmd_list(int argc, const char **argv, const char *prefix __maybe_unused)
 			free(s);
 		} else {
 			if (asprintf(&s, "*%s*", argv[i]) < 0) {
-				printf("Critical: Not enough memory! Trying to continue...\n");
+				if (!quiet)
+					printf("Critical: Not enough memory! Trying to continue...\n");
 				continue;
 			}
 			print_symbol_events(s, PERF_TYPE_HARDWARE,
-- 
2.11.0