Re: [PATCH v4 14/25] perf stat: Add default hybrid events

Jin, Yao
2021-04-22T02:13:16Z

Hi Jiri,

On 4/22/2021 2:29 AM, Jiri Olsa wrote:
> On Fri, Apr 16, 2021 at 10:05:06PM +0800, Jin Yao wrote:
>
> SNIP
>
>> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
>> index 1255af4751c2..0351b99d17a7 100644
>> --- a/tools/perf/builtin-stat.c
>> +++ b/tools/perf/builtin-stat.c
>> @@ -1145,6 +1145,13 @@ static int parse_stat_cgroups(const struct option *opt,
>> return parse_cgroups(opt, str, unset);
>> }
>>
>> +static int add_default_hybrid_events(struct evlist *evlist)
>> +{
>> + struct parse_events_error err;
>> +
>> + return parse_events(evlist, "cycles,instructions,branches,branch-misses", &err);
>> +}
>> +
>> static struct option stat_options[] = {
>> OPT_BOOLEAN('T', "transaction", &transaction_run,
>> "hardware transaction statistics"),
>> @@ -1626,6 +1633,12 @@ static int add_default_attributes(void)
>> { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
>> { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_BRANCH_MISSES },
>>
>> +};
>> + struct perf_event_attr default_sw_attrs[] = {
>> + { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_TASK_CLOCK },
>> + { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CONTEXT_SWITCHES },
>> + { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_MIGRATIONS },
>> + { .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_PAGE_FAULTS },
>
> hum, why not use default_attrs0, it's the same, no?
>

The default_attrs0 has one more item " {.type = PERF_TYPE_HARDWARE, .config =
PERF_COUNT_HW_CPU_CYCLES },"

So I have to only pick out the sw attrs and save them to default_sw_attrs.

>> };
>>
>> /*
>> @@ -1863,6 +1876,14 @@ static int add_default_attributes(void)
>> }
>>
>> if (!evsel_list->core.nr_entries) {
>> + if (perf_pmu__has_hybrid()) {
>> + if (evlist__add_default_attrs(evsel_list,
>> + default_sw_attrs) < 0) {
>> + return -1;
>> + }
>> + return add_default_hybrid_events(evsel_list);
>
> please do it the same way like when topdown calls parse events,
> we don't need to check for cycles, but please check result and
> display the error
>

Something like this?

err = parse_events(evsel_list, "cycles,instructions,branches,branch-misses", &errinfo);
if (err) {
fprintf(stderr,...);
parse_events_print_error(&errinfo, ...);
return -1;
}

>
>> + }
>> +
>> if (target__has_cpu(&target))
>> default_attrs0[0].config = PERF_COUNT_SW_CPU_CLOCK;
>
> also you still want this change for hybrid pmus as well
>

Yes, the default_sw_attr only uses 'PERF_COUNT_SW_TASK_CLOCK', we do need to change it to
PERF_COUNT_SW_CPU_CLOCK for system wide.

> thanks,
> jirka
>

Thanks
Jin Yao

>>
>> --
>> 2.17.1
>>
>