Re: [PATCH V1 02/23] libperf evsel: Add perf_evsel__enable_thread()

[Adrian Hunter]

On 6/05/22 01:48, Ian Rogers wrote:
> On Thu, May 5, 2022 at 9:56 AM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>>
>> Add perf_evsel__enable_thread() as a counterpart to
>> perf_evsel__enable_cpu(), to enable all events for a thread.
>>
>> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>> ---
>>  tools/lib/perf/evsel.c              | 10 ++++++++++
>>  tools/lib/perf/include/perf/evsel.h |  1 +
>>  2 files changed, 11 insertions(+)
>>
>> diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
>> index 20ae9f5f8b30..dcc928dd25f8 100644
>> --- a/tools/lib/perf/evsel.c
>> +++ b/tools/lib/perf/evsel.c
>> @@ -360,6 +360,16 @@ int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
>>         return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, cpu_map_idx);
>>  }
>>
>> +int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread)
>> +{
>> +       int err = 0;
>> +       int idx;
>> +
>> +       for (idx = 0; idx < xyarray__max_x(evsel->fd) && !err; idx++)
>> +               err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, idx, thread);
> 
> For perf_cpu_map code like this has been replaced with
> perf_cpu_map__for_each_cpu, it would be nice here to use a
> perf_thread_map__for_each_thread. I understand we don't have that at
> the moment. It would be easier to find places to add this if there is
> a call to perf_thread_map__nr. Adding an assert of:
> 
> assert(perf_thread_map__nr(evsel->thread_map) == xyarray__max_x(evsel->fd));

Threads go in the y direction.

I'll change it to use perf_cpu_map__for_each_cpu

> 
> Would help, or we could add the loop.
> 
> Thanks,
> Ian
> 
>> +       return err;
>> +}
>> +
>>  int perf_evsel__enable(struct perf_evsel *evsel)
>>  {
>>         int i;
>> diff --git a/tools/lib/perf/include/perf/evsel.h b/tools/lib/perf/include/perf/evsel.h
>> index 2a9516b42d15..699c0ed97d34 100644
>> --- a/tools/lib/perf/include/perf/evsel.h
>> +++ b/tools/lib/perf/include/perf/evsel.h
>> @@ -36,6 +36,7 @@ LIBPERF_API int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int
>>                                  struct perf_counts_values *count);
>>  LIBPERF_API int perf_evsel__enable(struct perf_evsel *evsel);
>>  LIBPERF_API int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
>> +LIBPERF_API int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread);
>>  LIBPERF_API int perf_evsel__disable(struct perf_evsel *evsel);
>>  LIBPERF_API int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
>>  LIBPERF_API struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel);
>> --
>> 2.25.1
>>