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

Alexey Budankov
2020-05-07T08:58:56Z

On 06.05.2020 23:23, Arnaldo Carvalho de Melo wrote:
> 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?

It already exists on lower level, at perf_evlist__ctlfd_process() (see patch 02/11).

~Alexey