perf evlist: Refactor evlist__for_each_cpu()

Previously evlist__for_each_cpu() needed to iterate over the evlist in
an inner loop and call "skip" routines. Refactor this so that the
iteratr is smarter and the next function can update both the current CPU
and evsel.

By using a cpu map index, fix apparent off-by-1 in __run_perf_stat's
call to perf_evsel__close_cpu().

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-35-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 81 insertions, 65 deletions

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 5f92319ce258..39d294f6c321 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -342,36 +342,65 @@ static int evlist__nr_threads(struct evlist *evlist, struct evsel *evsel)
 		return perf_thread_map__nr(evlist->core.threads);
 }
 
-void evlist__cpu_iter_start(struct evlist *evlist)
-{
-	struct evsel *pos;
-
-	/*
-	 * Reset the per evsel cpu_iter. This is needed because
-	 * each evsel's cpumap may have a different index space,
-	 * and some operations need the index to modify
-	 * the FD xyarray (e.g. open, close)
-	 */
-	evlist__for_each_entry(evlist, pos)
-		pos->cpu_iter = 0;
-}
+struct evlist_cpu_iterator evlist__cpu_begin(struct evlist *evlist, struct affinity *affinity)
+{
+	struct evlist_cpu_iterator itr = {
+		.container = evlist,
+		.evsel = evlist__first(evlist),
+		.cpu_map_idx = 0,
+		.evlist_cpu_map_idx = 0,
+		.evlist_cpu_map_nr = perf_cpu_map__nr(evlist->core.all_cpus),
+		.cpu = -1,
+		.affinity = affinity,
+	};
 
-bool evsel__cpu_iter_skip_no_inc(struct evsel *ev, int cpu)
-{
-	if (ev->cpu_iter >= ev->core.cpus->nr)
-		return true;
-	if (cpu >= 0 && ev->core.cpus->map[ev->cpu_iter] != cpu)
-		return true;
-	return false;
+	if (itr.affinity) {
+		itr.cpu = perf_cpu_map__cpu(evlist->core.all_cpus, 0);
+		affinity__set(itr.affinity, itr.cpu);
+		itr.cpu_map_idx = perf_cpu_map__idx(itr.evsel->core.cpus, itr.cpu);
+		/*
+		 * If this CPU isn't in the evsel's cpu map then advance through
+		 * the list.
+		 */
+		if (itr.cpu_map_idx == -1)
+			evlist_cpu_iterator__next(&itr);
+	}
+	return itr;
+}
+
+void evlist_cpu_iterator__next(struct evlist_cpu_iterator *evlist_cpu_itr)
+{
+	while (evlist_cpu_itr->evsel != evlist__last(evlist_cpu_itr->container)) {
+		evlist_cpu_itr->evsel = evsel__next(evlist_cpu_itr->evsel);
+		evlist_cpu_itr->cpu_map_idx =
+			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
+					  evlist_cpu_itr->cpu);
+		if (evlist_cpu_itr->cpu_map_idx != -1)
+			return;
+	}
+	evlist_cpu_itr->evlist_cpu_map_idx++;
+	if (evlist_cpu_itr->evlist_cpu_map_idx < evlist_cpu_itr->evlist_cpu_map_nr) {
+		evlist_cpu_itr->evsel = evlist__first(evlist_cpu_itr->container);
+		evlist_cpu_itr->cpu =
+			perf_cpu_map__cpu(evlist_cpu_itr->container->core.all_cpus,
+					  evlist_cpu_itr->evlist_cpu_map_idx);
+		if (evlist_cpu_itr->affinity)
+			affinity__set(evlist_cpu_itr->affinity, evlist_cpu_itr->cpu);
+		evlist_cpu_itr->cpu_map_idx =
+			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
+					  evlist_cpu_itr->cpu);
+		/*
+		 * If this CPU isn't in the evsel's cpu map then advance through
+		 * the list.
+		 */
+		if (evlist_cpu_itr->cpu_map_idx == -1)
+			evlist_cpu_iterator__next(evlist_cpu_itr);
+	}
 }
 
-bool evsel__cpu_iter_skip(struct evsel *ev, int cpu)
+bool evlist_cpu_iterator__end(const struct evlist_cpu_iterator *evlist_cpu_itr)
 {
-	if (!evsel__cpu_iter_skip_no_inc(ev, cpu)) {
-		ev->cpu_iter++;
-		return false;
-	}
-	return true;
+	return evlist_cpu_itr->evlist_cpu_map_idx >= evlist_cpu_itr->evlist_cpu_map_nr;
 }
 
 static int evsel__strcmp(struct evsel *pos, char *evsel_name)
@@ -400,31 +429,26 @@ static int evlist__is_enabled(struct evlist *evlist)
 static void __evlist__disable(struct evlist *evlist, char *evsel_name)
 {
 	struct evsel *pos;
+	struct evlist_cpu_iterator evlist_cpu_itr;
 	struct affinity affinity;
-	int cpu, i, imm = 0;
 	bool has_imm = false;
 
 	if (affinity__setup(&affinity) < 0)
 		return;
 
 	/* Disable 'immediate' events last */
-	for (imm = 0; imm <= 1; imm++) {
-		evlist__for_each_cpu(evlist, i, cpu) {
-			affinity__set(&affinity, cpu);
-
-			evlist__for_each_entry(evlist, pos) {
-				if (evsel__strcmp(pos, evsel_name))
-					continue;
-				if (evsel__cpu_iter_skip(pos, cpu))
-					continue;
-				if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
-					continue;
-				if (pos->immediate)
-					has_imm = true;
-				if (pos->immediate != imm)
-					continue;
-				evsel__disable_cpu(pos, pos->cpu_iter - 1);
-			}
+	for (int imm = 0; imm <= 1; imm++) {
+		evlist__for_each_cpu(evlist_cpu_itr, evlist, &affinity) {
+			pos = evlist_cpu_itr.evsel;
+			if (evsel__strcmp(pos, evsel_name))
+				continue;
+			if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
+				continue;
+			if (pos->immediate)
+				has_imm = true;
+			if (pos->immediate != imm)
+				continue;
+			evsel__disable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
 		}
 		if (!has_imm)
 			break;
@@ -462,24 +486,19 @@ void evlist__disable_evsel(struct evlist *evlist, char *evsel_name)
 static void __evlist__enable(struct evlist *evlist, char *evsel_name)
 {
 	struct evsel *pos;
+	struct evlist_cpu_iterator evlist_cpu_itr;
 	struct affinity affinity;
-	int cpu, i;
 
 	if (affinity__setup(&affinity) < 0)
 		return;
 
-	evlist__for_each_cpu(evlist, i, cpu) {
-		affinity__set(&affinity, cpu);
-
-		evlist__for_each_entry(evlist, pos) {
-			if (evsel__strcmp(pos, evsel_name))
-				continue;
-			if (evsel__cpu_iter_skip(pos, cpu))
-				continue;
-			if (!evsel__is_group_leader(pos) || !pos->core.fd)
-				continue;
-			evsel__enable_cpu(pos, pos->cpu_iter - 1);
-		}
+	evlist__for_each_cpu(evlist_cpu_itr, evlist, &affinity) {
+		pos = evlist_cpu_itr.evsel;
+		if (evsel__strcmp(pos, evsel_name))
+			continue;
+		if (!evsel__is_group_leader(pos) || !pos->core.fd)
+			continue;
+		evsel__enable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
 	}
 	affinity__cleanup(&affinity);
 	evlist__for_each_entry(evlist, pos) {
@@ -1264,8 +1283,8 @@ void evlist__set_selected(struct evlist *evlist, struct evsel *evsel)
 void evlist__close(struct evlist *evlist)
 {
 	struct evsel *evsel;
+	struct evlist_cpu_iterator evlist_cpu_itr;
 	struct affinity affinity;
-	int cpu, i;
 
 	/*
 	 * With perf record core.cpus is usually NULL.
@@ -1279,15 +1298,12 @@ void evlist__close(struct evlist *evlist)
 
 	if (affinity__setup(&affinity) < 0)
 		return;
-	evlist__for_each_cpu(evlist, i, cpu) {
-		affinity__set(&affinity, cpu);
 
-		evlist__for_each_entry_reverse(evlist, evsel) {
-			if (evsel__cpu_iter_skip(evsel, cpu))
-			    continue;
-			perf_evsel__close_cpu(&evsel->core, evsel->cpu_iter - 1);
-		}
+	evlist__for_each_cpu(evlist_cpu_itr, evlist, &affinity) {
+		perf_evsel__close_cpu(&evlist_cpu_itr.evsel->core,
+				      evlist_cpu_itr.cpu_map_idx);
 	}
+
 	affinity__cleanup(&affinity);
 	evlist__for_each_entry_reverse(evlist, evsel) {
 		perf_evsel__free_fd(&evsel->core);