[PATCH v1 7/8] perf record: implement resume and pause control commands handling

[Alexey Budankov]

Implement handling of events coming from control file descriptor.

Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
 tools/perf/builtin-record.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index f99751943b40..ae6f7d08e472 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1418,6 +1418,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 	struct evlist *sb_evlist = NULL;
 	int fd;
 	float ratio = 0;
+	enum evlist_ctl_cmd cmd = CTL_CMD_UNSUPPORTED;
 
 	atexit(record__sig_exit);
 	signal(SIGCHLD, sig_handler);
@@ -1620,6 +1621,8 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 		perf_evlist__start_workload(rec->evlist);
 	}
 
+	perf_evlist__initialize_ctlfd(rec->evlist, opts->ctl_fd, opts->ctl_fd_ack);
+
 	if (opts->initial_delay) {
 		pr_info(PERF_EVLIST__PAUSED_MSG);
 		if (opts->initial_delay > 0) {
@@ -1710,8 +1713,23 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 			 * Propagate error, only if there's any. Ignore positive
 			 * number of returned events and interrupt error.
 			 */
-			if (err > 0 || (err < 0 && errno == EINTR))
+			if (err > 0 || (err < 0 && errno == EINTR)) {
 				err = 0;
+				if (perf_evlist__ctlfd_process(rec->evlist, &cmd) > 0) {
+					switch (cmd) {
+					case CTL_CMD_RESUME:
+						pr_info(PERF_EVLIST__RESUMED_MSG);
+						break;
+					case CTL_CMD_PAUSE:
+						pr_info(PERF_EVLIST__PAUSED_MSG);
+						break;
+					case CTL_CMD_ACK:
+					case CTL_CMD_UNSUPPORTED:
+					default:
+						break;
+					}
+				}
+			}
 			waking++;
 
 			if (evlist__filter_pollfd(rec->evlist, POLLERR | POLLHUP) == 0)
@@ -1751,6 +1769,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
 		record__synthesize_workload(rec, true);
 
 out_child:
+	perf_evlist__finalize_ctlfd(rec->evlist);
 	record__mmap_read_all(rec, true);
 	record__aio_mmap_read_sync(rec);
 
-- 
2.24.1