Re: [PATCH RFC 02/21] libperf evsel: Add perf_evsel__enable_thread()

From: Adrian Hunter
Date: Thu Apr 28 2022 - 00:15:35 EST


On 28/04/22 00:48, Namhyung Kim wrote:
> Hi Adrian,
>
> On Fri, Apr 22, 2022 at 9:24 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..2a1f07f877be 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 i;
>> +
>> + for (i = 0; i < xyarray__max_x(evsel->fd) && !err; i++)
>> + err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, i, thread);
>
> You might want to break the loop when it fails.

Thanks for looking at this. It should break because of " && !err".

>
> Thanks,
> Namhyung
>
>
>> + 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
>>