perf auxtrace arm: Refactor event list iteration in auxtrace_record__init()

Add find_pmu_for_event() and use to simplify logic in
auxtrace_record_init(). find_pmu_for_event() will be reused in
subsequent patches.

Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Liu <liuqi6124@gmail.com>
Cc: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zeng Prime <prime.zeng@huawei.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: linuxarm@huawei.com
Link: https://lore.kernel.org/r/20220927081400.14364-2-yangyicong@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: 77liuqi

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;
 	}