perf evlist: New command to list the names of events present in a perf.data file

[root@emilia ~]# perf record -a -e sched:* -e timer:timer* sleep 5
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.172 MB perf.data (~7530 samples) ]
[root@emilia ~]# perf evlist
sched:sched_kthread_stop
sched:sched_kthread_stop_ret
sched:sched_wakeup
sched:sched_wakeup_new
sched:sched_switch
sched:sched_migrate_task
sched:sched_process_free
sched:sched_process_exit
sched:sched_wait_task
sched:sched_process_wait
sched:sched_process_fork
sched:sched_stat_wait
sched:sched_stat_sleep
sched:sched_stat_iowait
sched:sched_stat_runtime
sched:sched_pi_setprio
timer:timer_init
timer:timer_start
timer:timer_expire_entry
timer:timer_expire_exit
timer:timer_cancel
[root@emilia ~]#

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-evlist.c b/tools/perf/builtin-evlist.c
new file mode 100644
index 0000000..4c5e9e0
--- /dev/null
+++ b/tools/perf/builtin-evlist.c
@@ -0,0 +1,54 @@
+/*
+ * Builtin evlist command: Show the list of event selectors present
+ * in a perf.data file.
+ */
+#include "builtin.h"
+
+#include "util/util.h"
+
+#include <linux/list.h>
+
+#include "perf.h"
+#include "util/evlist.h"
+#include "util/evsel.h"
+#include "util/parse-events.h"
+#include "util/parse-options.h"
+#include "util/session.h"
+
+static char const *input_name = "perf.data";
+
+static int __cmd_evlist(void)
+{
+	struct perf_session *session;
+	struct perf_evsel *pos;
+
+	session = perf_session__new(input_name, O_RDONLY, 0, false, NULL);
+	if (session == NULL)
+		return -ENOMEM;
+
+	list_for_each_entry(pos, &session->evlist->entries, node)
+		printf("%s\n", event_name(pos));
+
+	perf_session__delete(session);
+	return 0;
+}
+
+static const char * const evlist_usage[] = {
+	"perf evlist [<options>]",
+	NULL
+};
+
+static const struct option options[] = {
+	OPT_STRING('i', "input", &input_name, "file",
+		    "input file name"),
+	OPT_END()
+};
+
+int cmd_evlist(int argc, const char **argv, const char *prefix __used)
+{
+	argc = parse_options(argc, argv, options, evlist_usage, 0);
+	if (argc)
+		usage_with_options(evlist_usage, options);
+
+	return __cmd_evlist();
+}