perf stat: Support regex pattern in --for-each-cgroup

To make the command line even more compact with cgroups, support regex
pattern matching in cgroup names.

  $ perf stat -a -e cpu-clock,cycles --for-each-cgroup ^foo sleep 1

          3,000.73 msec cpu-clock                 foo #    2.998 CPUs utilized
    12,530,992,699      cycles                    foo #    7.517 GHz                      (100.00%)
          1,000.61 msec cpu-clock                 foo/bar #    1.000 CPUs utilized
     4,178,529,579      cycles                    foo/bar #    2.506 GHz                      (100.00%)
          1,000.03 msec cpu-clock                 foo/baz #    0.999 CPUs utilized
     4,176,104,315      cycles                    foo/baz #    2.505 GHz                      (100.00%)

       1.000892614 seconds time elapsed

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201027072855.655449-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index b01af171d94f..6709578128c9 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -2235,8 +2235,11 @@ int cmd_stat(int argc, const char **argv)
 		}
 
 		if (evlist__expand_cgroup(evsel_list, stat_config.cgroup_list,
-					  &stat_config.metric_events, true) < 0)
+					  &stat_config.metric_events, true) < 0) {
+			parse_options_usage(stat_usage, stat_options,
+					    "for-each-cgroup", 0);
 			goto out;
+		}
 	}
 
 	target__validate(&target);