[RFC PATCH v5 06/16] perf stat: Add functions to get counter info

[weilin . wang]

From: Weilin Wang <weilin.wang@xxxxxxxxx>

Add data structure metricgroup__pmu_counters to represent hardware counters
available in the system.

Add functions to parse pmu-events and create the list of pmu_info_list to
hold the counter information of the system.

Add functions to free pmu_info_list and event_info_list before exit
grouping for hardware-grouping method

This method would fall back to normal grouping when event json files do not
support hardware aware grouping.

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>
Signed-off-by: Weilin Wang <weilin.wang@xxxxxxxxx>
---
 tools/perf/util/metricgroup.c | 115 +++++++++++++++++++++++++++++++++-
 1 file changed, 112 insertions(+), 3 deletions(-)

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 1a7ac17f7ae1..78a5410cdc09 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -183,6 +183,21 @@ struct metricgroup__event_info {
 	DECLARE_BITMAP(counters, NR_COUNTERS);
 };
 
+/**
+ * A node is the counter availability of a pmu.
+ * This info is built up at the beginning from JSON file and
+ * used as a reference in metric grouping process.
+ */
+struct metricgroup__pmu_counters {
+	struct list_head nd;
+	/** The name of the pmu the event collected on. */
+	const char *name;
+	/** The number of gp counters in the pmu. */
+	size_t counters_num_gp;
+	/** The number of fixed counters in the pmu. */
+	size_t counters_num_fixed;
+};
+
 /**
  * Each group is one node in the group string list.
  */
@@ -1534,6 +1549,40 @@ static int parse_counter(const char *counter,
 	return 0;
 }
 
+static void metricgroup__event_info__delete(struct metricgroup__event_info *e)
+{
+	zfree(&e->name);
+	zfree(&e->pmu_name);
+	free(e);
+}
+
+static void metricgroup__pmu_counter__delete(struct metricgroup__pmu_counters *p)
+{
+	zfree(&p->name);
+	free(p);
+}
+
+static void metricgroup__free_event_info(struct list_head
+					*event_info_list)
+{
+	struct metricgroup__event_info *e, *tmp;
+
+	list_for_each_entry_safe(e, tmp, event_info_list, nd) {
+		list_del_init(&e->nd);
+		metricgroup__event_info__delete(e);
+	}
+}
+
+static void metricgroup__free_pmu_info(struct list_head *pmu_info_list)
+{
+	struct metricgroup__pmu_counters *p, *tmp;
+
+	list_for_each_entry_safe(p, tmp, pmu_info_list, nd) {
+		list_del_init(&p->nd);
+		metricgroup__pmu_counter__delete(p);
+	}
+}
+
 static struct metricgroup__event_info *event_info__new(const char *name,
 						      const char *pmu_name,
 						      const char *counter,
@@ -1589,7 +1638,9 @@ static int metricgroup__add_metric_event_callback(const struct pmu_event *pe,
 	struct metricgroup__add_metric_event_data *d = data;
 
 	if (!strcasecmp(pe->name, d->event_name)) {
-		event = event_info__new(d->event_id, pe->pmu, pe->counter, /*free_counter=*/false);
+		if (!pe->counters_list)
+			return -EINVAL;
+		event = event_info__new(d->event_id, pe->pmu, pe->counters_list, /*free_counter=*/false);
 		if (!event)
 			return -ENOMEM;
 		list_add(&event->nd, d->list);
@@ -1630,7 +1681,7 @@ static int get_metricgroup_events(const char *full_id,
 			.event_name = id,
 			.event_id = full_id,
 		};
-		ret = pmu_events_table_for_each_event(table,
+		ret = pmu_events_table__for_each_event(table, /*pmu=*/NULL,
 				metricgroup__add_metric_event_callback, &data);
 	}
 
@@ -1639,6 +1690,59 @@ static int get_metricgroup_events(const char *full_id,
 	return ret;
 }
 
+static struct metricgroup__pmu_counters *pmu_layout__new(const struct pmu_layout *pl)
+{
+	struct metricgroup__pmu_counters *l;
+
+	l = zalloc(sizeof(*l));
+
+	if (!l)
+		return NULL;
+
+	l->name = strdup(pl->pmu);
+	if (!l->name)
+		return NULL;
+	l->counters_num_gp = pl->counters_num_gp;
+	l->counters_num_fixed = pl->counters_num_fixed;
+	pr_debug("create new pmu_layout: [pmu]=%s, [gp_size]=%ld, [fixed_size]=%ld\n",
+		l->name, l->counters_num_gp, l->counters_num_fixed);
+	return l;
+}
+
+static int metricgroup__add_pmu_layout_callback(const struct pmu_layout *pl,
+						void *data)
+{
+	struct metricgroup__pmu_counters *pmu;
+	struct list_head *d = data;
+	int ret = 0;
+
+	pmu = pmu_layout__new(pl);
+	if (!pmu)
+		return -ENOMEM;
+	list_add(&pmu->nd, d);
+	return ret;
+}
+
+/**
+ * get_pmu_counter_layouts - Find counter info of the architecture from
+ * the pmu_layouts table
+ * @pmu_info_list: the list that the new counter info of a pmu is added to.
+ * @table: pmu_layouts table that is searched for counter info.
+ */
+static int get_pmu_counter_layouts(struct list_head *pmu_info_list,
+				   const struct pmu_layouts_table
+				   *table)
+{
+	LIST_HEAD(list);
+	int ret;
+
+	ret = pmu_layouts_table__for_each_layout(table,
+						metricgroup__add_pmu_layout_callback, &list);
+
+	list_splice(&list, pmu_info_list);
+	return ret;
+}
+
 /**
  * hw_aware_build_grouping - Build event groupings by reading counter
  * requirement of the events and counter available on the system from
@@ -1657,6 +1761,7 @@ static int hw_aware_build_grouping(struct expr_parse_ctx *ctx __maybe_unused,
 	LIST_HEAD(event_info_list);
 	size_t bkt;
 	const struct pmu_events_table *etable = perf_pmu__find_events_table(NULL);
+	const struct pmu_layouts_table *ltable = perf_pmu__find_layouts_table(NULL);
 
 #define RETURN_IF_NON_ZERO(x) do { if (x) return x; } while (0)
 	hashmap__for_each_entry(ctx->ids, cur, bkt) {
@@ -1666,9 +1771,13 @@ static int hw_aware_build_grouping(struct expr_parse_ctx *ctx __maybe_unused,
 
 		ret = get_metricgroup_events(id, etable, &event_info_list);
 		if (ret)
-			return ret;
+			goto err_out;
 	}
+	ret = get_pmu_counter_layouts(&pmu_info_list, ltable);
 
+err_out:
+	metricgroup__free_event_info(&event_info_list);
+	metricgroup__free_pmu_info(&pmu_info_list);
 	return ret;
 #undef RETURN_IF_NON_ZERO
 }
-- 
2.42.0