On Wed, Sep 14, 2022 at 02:47:43PM +0100, John Garry wrote:
[...]
> > 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);
>
> should you break if found_etm and found_spe are set? Or, indeed, error and
> return directly as we do below? Indeed, I am not sure why you even require
> auxtrace_event_cnt
I think this was my suggestion :)
We can check if both 'found_etm' and 'found_spe' are set and directly
break (and bail out) for this case. But it would introduce more complex
checking if we connect with patch 2 with new flag 'found_ptt', something
like:
if ((found_etm && found_spe) ||
(found_etm && found_ptt) ||
(found_spe && found_ptt))
break;
This is hard for later's extension if we need to support a new auxtrace
event, so using auxtrace_event_cnt would be easier to extend more
auxtrace event on Arm platforms.
Thanks,
Leo
> > }
> > +
> > 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;
> > }
>
