[PATCH v2 09/11] perf record: implement control commands handling

From: Alexey Budankov
Date: Wed May 06 2020 - 14:29:16 EST



Implement handling of 'enable' and 'disable' control commands
coming from control file descriptor.

Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
tools/perf/builtin-record.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 8a14e68b86ad..2278a3efc747 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1496,6 +1496,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
bool disabled = false, draining = false;
int fd;
float ratio = 0;
+ enum evlist_ctl_cmd cmd = CTL_CMD_UNSUPPORTED;

atexit(record__sig_exit);
signal(SIGCHLD, sig_handler);
@@ -1793,8 +1794,23 @@ 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_ENABLE:
+ pr_info(PERF_EVLIST__ENABLED_MSG);
+ break;
+ case CTL_CMD_DISABLE:
+ pr_info(PERF_EVLIST__DISABLED_MSG);
+ break;
+ case CTL_CMD_ACK:
+ case CTL_CMD_UNSUPPORTED:
+ default:
+ break;
+ }
+ }
+ }
waking++;

if (evlist__filter_pollfd(rec->evlist, POLLERR | POLLHUP) == 0)
--
2.24.1