[PATCH v8 4/8] perf arm: Refactor event list iteration in auxtrace_record__init()

[liuqi (BA)]

On 2022/5/17 0:29, John Garry wrote:
> On 16/05/2022 13:52, Yicong Yang wrote:
> 
> As requested before, please mention "perf tool" in the commit subject
"perf arm" is used referenced to previous commit, ok, will mention "perf 
tool" in the commit subject next time.

Thanks,
Qi
> 
>> From: Qi Liu <liuqi115 at huawei.com>
>>
>> Use find_pmu_for_event() to simplify logic in auxtrace_record__init().
>>
>> Signed-off-by: Qi Liu <liuqi115 at huawei.com>
>> Signed-off-by: Yicong Yang <yangyicong at hisilicon.com>
>> ---
>>   tools/perf/arch/arm/util/auxtrace.c | 53 ++++++++++++++++++-----------
>>   1 file changed, 34 insertions(+), 19 deletions(-)
>>
>> diff --git a/tools/perf/arch/arm/util/auxtrace.c 
>> b/tools/perf/arch/arm/util/auxtrace.c
>> index 5fc6a2a3dbc5..384c7cfda0fd 100644
>> --- a/tools/perf/arch/arm/util/auxtrace.c
>> +++ b/tools/perf/arch/arm/util/auxtrace.c
>> @@ -50,16 +50,32 @@ static struct perf_pmu **find_all_arm_spe_pmus(int 
>> *nr_spes, int *err)
>>       return arm_spe_pmus;
>>   }
>> +static struct perf_pmu *find_pmu_for_event(struct perf_pmu **pmus,
>> +                       int pmu_nr, struct evsel *evsel)
>> +{
>> +    int i;
>> +
>> +    if (!pmus)
>> +        return NULL;
>> +
>> +    for (i = 0; i < pmu_nr; i++) {
>> +        if (evsel->core.attr.type == pmus[i]->type)
>> +            return pmus[i];
>> +    }
>> +
>> +    return NULL;
>> +}
>> +
>>   struct auxtrace_record
>>   *auxtrace_record__init(struct evlist *evlist, int *err)
>>   {
>> -    struct perf_pmu    *cs_etm_pmu;
>> +    struct perf_pmu    *cs_etm_pmu = NULL;
>> +    struct perf_pmu **arm_spe_pmus = NULL;
>>       struct evsel *evsel;
>> -    bool found_etm = false;
>> +    struct perf_pmu *found_etm = NULL;
>>       struct perf_pmu *found_spe = NULL;
>> -    struct perf_pmu **arm_spe_pmus = NULL;
>> +    int auxtrace_event_cnt = 0;
>>       int nr_spes = 0;
>> -    int i = 0;
>>       if (!evlist)
>>           return NULL;
>> @@ -68,24 +84,23 @@ struct auxtrace_record
>>       arm_spe_pmus = find_all_arm_spe_pmus(&nr_spes, err);
>>       evlist__for_each_entry(evlist, evsel) {
>> -        if (cs_etm_pmu &&
>> -            evsel->core.attr.type == cs_etm_pmu->type)
>> -            found_etm = true;
>> -
>> -        if (!nr_spes || found_spe)
>> -            continue;
>> -
>> -        for (i = 0; i < nr_spes; i++) {
>> -            if (evsel->core.attr.type == arm_spe_pmus[i]->type) {
>> -                found_spe = arm_spe_pmus[i];
>> -                break;
>> -            }
>> -        }
>> +        if (cs_etm_pmu && !found_etm)
>> +            found_etm = find_pmu_for_event(&cs_etm_pmu, 1, evsel);
>> +
>> +        if (arm_spe_pmus && !found_spe)
>> +            found_spe = find_pmu_for_event(arm_spe_pmus, nr_spes, 
>> evsel);
>>       }
>> +
>>       free(arm_spe_pmus);
>> -    if (found_etm && found_spe) {
>> -        pr_err("Concurrent ARM Coresight ETM and SPE operation not 
>> currently supported\n");
>> +    if (found_etm)
>> +        auxtrace_event_cnt++;
>> +
>> +    if (found_spe)
>> +        auxtrace_event_cnt++;
>> +
>> +    if (auxtrace_event_cnt > 1) {
>> +        pr_err("Concurrent AUX trace operation not currently 
>> supported\n");
>>           *err = -EOPNOTSUPP;
>>           return NULL;
>>       }
> 
> .