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

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

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