Re: [PATCH v4 10/10] perf record: introduce --ctl-fd[-ack] options

[Alexey Budankov]

On 03.06.2020 15:05, Adrian Hunter wrote:
> On 25/05/20 5:23 pm, Alexey Budankov wrote:
>>
>> Introduce --ctl-fd[-ack] options to pass open file descriptors numbers
>> from command line. Extend perf-record.txt file with --ctl-fd[-ack]
>> options description. Document possible usage model introduced by
>> --ctl-fd[-ack] options by providing example bash shell script.
>>
>> Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
>> ---
>>  tools/perf/Documentation/perf-record.txt | 39 ++++++++++++++++++++++++
>>  tools/perf/builtin-record.c              | 10 ++++++
>>  tools/perf/util/record.h                 |  2 ++
>>  3 files changed, 51 insertions(+)
>>
>> diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
>> index c2c4ce7ccee2..5c012cfe68a4 100644
>> --- a/tools/perf/Documentation/perf-record.txt
>> +++ b/tools/perf/Documentation/perf-record.txt
>> @@ -614,6 +614,45 @@ appended unit character - B/K/M/G
>>  	The number of threads to run when synthesizing events for existing processes.
>>  	By default, the number of threads equals 1.
>>  
>> +--ctl-fd::
>> +--ctl-fd-ack::
>> +Listen on ctl-fd descriptor for command to control measurement ('enable': enable events,
>> +'disable': disable events. Optionally send control command completion ('ack') to fd-ack
>> +descriptor to synchronize with the controlling process. 
> 
> You should also explain the use of --delay=-1 here.

Well, possibly like this:

"Listen on ctl-fd descriptor for command to control measurement ('enable': enable events,
 'disable': disable events). Measurements can be started paused using --delay=-1 option.
 Optionally send control command completion ('ack') to fd-ack descriptor to synchronize
 with the controlling process. Example of bash shell script to enable and disable events
 during measurements:"