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

Arnaldo Carvalho de Melo
2020-05-06T20:23:45Z

Em Wed, May 06, 2020 at 09:29:05PM +0300, Alexey Budankov escreveu:
>
> Implement handling of 'enable' and 'disable' control commands
> coming from control file descriptor.
>
> Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
> ---
> 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:

Shouldn't we have a pr_debug() or even pr_err() for the unsupported one?

> + default:
> + break;
> + }
> + }
> + }
> waking++;
>
> if (evlist__filter_pollfd(rec->evlist, POLLERR | POLLHUP) == 0)
> --
> 2.24.1
>
>

--

- Arnaldo