1 files changed, 115 insertions, 43 deletions

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 02aee946b6c1..926449a7cdbf 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -22,6 +22,8 @@
 #include <linux/string.h>
 #include <linux/zalloc.h>
 #include <subcmd/parse-options.h>
+#include <api/fs/fs.h>
+#include "util.h"
 
 struct metric_event *metricgroup__lookup(struct rblist *metric_events,
 					 struct evsel *evsel,
@@ -93,13 +95,16 @@ struct egroup {
 static struct evsel *find_evsel_group(struct evlist *perf_evlist,
 				      const char **ids,
 				      int idnum,
-				      struct evsel **metric_events)
+				      struct evsel **metric_events,
+				      bool *evlist_used)
 {
 	struct evsel *ev;
-	int i = 0;
+	int i = 0, j = 0;
 	bool leader_found;
 
 	evlist__for_each_entry (perf_evlist, ev) {
+		if (evlist_used[j++])
+			continue;
 		if (!strcmp(ev->name, ids[i])) {
 			if (!metric_events[i])
 				metric_events[i] = ev;
@@ -107,22 +112,17 @@ static struct evsel *find_evsel_group(struct evlist *perf_evlist,
 			if (i == idnum)
 				break;
 		} else {
-			if (i + 1 == idnum) {
-				/* Discard the whole match and start again */
-				i = 0;
-				memset(metric_events, 0,
-				       sizeof(struct evsel *) * idnum);
-				continue;
-			}
-
-			if (!strcmp(ev->name, ids[i]))
-				metric_events[i] = ev;
-			else {
-				/* Discard the whole match and start again */
-				i = 0;
-				memset(metric_events, 0,
-				       sizeof(struct evsel *) * idnum);
-				continue;
+			/* Discard the whole match and start again */
+			i = 0;
+			memset(metric_events, 0,
+				sizeof(struct evsel *) * idnum);
+
+			if (!strcmp(ev->name, ids[i])) {
+				if (!metric_events[i])
+					metric_events[i] = ev;
+				i++;
+				if (i == idnum)
+					break;
 			}
 		}
 	}
@@ -144,7 +144,10 @@ static struct evsel *find_evsel_group(struct evlist *perf_evlist,
 			    !strcmp(ev->name, metric_events[i]->name)) {
 				ev->metric_leader = metric_events[i];
 			}
+			j++;
 		}
+		ev = metric_events[i];
+		evlist_used[ev->idx] = true;
 	}
 
 	return metric_events[0];
@@ -160,6 +163,13 @@ static int metricgroup__setup_events(struct list_head *groups,
 	int ret = 0;
 	struct egroup *eg;
 	struct evsel *evsel;
+	bool *evlist_used;
+
+	evlist_used = calloc(perf_evlist->core.nr_entries, sizeof(bool));
+	if (!evlist_used) {
+		ret = -ENOMEM;
+		return ret;
+	}
 
 	list_for_each_entry (eg, groups, nd) {
 		struct evsel **metric_events;
@@ -170,7 +180,7 @@ static int metricgroup__setup_events(struct list_head *groups,
 			break;
 		}
 		evsel = find_evsel_group(perf_evlist, eg->ids, eg->idnum,
-					 metric_events);
+					 metric_events, evlist_used);
 		if (!evsel) {
 			pr_debug("Cannot resolve %s: %s\n",
 					eg->metric_name, eg->metric_expr);
@@ -194,6 +204,9 @@ static int metricgroup__setup_events(struct list_head *groups,
 		expr->metric_events = metric_events;
 		list_add(&expr->nd, &me->head);
 	}
+
+	free(evlist_used);
+
 	return ret;
 }
 
@@ -399,13 +412,85 @@ void metricgroup__print(bool metrics, bool metricgroups, char *filter,
 	strlist__delete(metriclist);
 }
 
+static void metricgroup__add_metric_weak_group(struct strbuf *events,
+					       const char **ids,
+					       int idnum)
+{
+	bool no_group = false;
+	int i;
+
+	for (i = 0; i < idnum; i++) {
+		pr_debug("found event %s\n", ids[i]);
+		/*
+		 * Duration time maps to a software event and can make
+		 * groups not count. Always use it outside a
+		 * group.
+		 */
+		if (!strcmp(ids[i], "duration_time")) {
+			if (i > 0)
+				strbuf_addf(events, "}:W,");
+			strbuf_addf(events, "duration_time");
+			no_group = true;
+			continue;
+		}
+		strbuf_addf(events, "%s%s",
+			i == 0 || no_group ? "{" : ",",
+			ids[i]);
+		no_group = false;
+	}
+	if (!no_group)
+		strbuf_addf(events, "}:W");
+}
+
+static void metricgroup__add_metric_non_group(struct strbuf *events,
+					      const char **ids,
+					      int idnum)
+{
+	int i;
+
+	for (i = 0; i < idnum; i++)
+		strbuf_addf(events, ",%s", ids[i]);
+}
+
+static void metricgroup___watchdog_constraint_hint(const char *name, bool foot)
+{
+	static bool violate_nmi_constraint;
+
+	if (!foot) {
+		pr_warning("Splitting metric group %s into standalone metrics.\n", name);
+		violate_nmi_constraint = true;
+		return;
+	}
+
+	if (!violate_nmi_constraint)
+		return;
+
+	pr_warning("Try disabling the NMI watchdog to comply NO_NMI_WATCHDOG metric constraint:\n"
+		   "    echo 0 > /proc/sys/kernel/nmi_watchdog\n"
+		   "    perf stat ...\n"
+		   "    echo 1 > /proc/sys/kernel/nmi_watchdog\n");
+}
+
+static bool metricgroup__has_constraint(struct pmu_event *pe)
+{
+	if (!pe->metric_constraint)
+		return false;
+
+	if (!strcmp(pe->metric_constraint, "NO_NMI_WATCHDOG") &&
+	    sysctl__nmi_watchdog_enabled()) {
+		metricgroup___watchdog_constraint_hint(pe->metric_name, false);
+		return true;
+	}
+
+	return false;
+}
+
 static int metricgroup__add_metric(const char *metric, struct strbuf *events,
 				   struct list_head *group_list)
 {
 	struct pmu_events_map *map = perf_pmu__find_map(NULL);
 	struct pmu_event *pe;
-	int ret = -EINVAL;
-	int i, j;
+	int i, ret = -EINVAL;
 
 	if (!map)
 		return 0;
@@ -422,7 +507,6 @@ static int metricgroup__add_metric(const char *metric, struct strbuf *events,
 			const char **ids;
 			int idnum;
 			struct egroup *eg;
-			bool no_group = false;
 
 			pr_debug("metric expr %s for %s\n", pe->metric_expr, pe->metric_name);
 
@@ -431,27 +515,11 @@ static int metricgroup__add_metric(const char *metric, struct strbuf *events,
 				continue;
 			if (events->len > 0)
 				strbuf_addf(events, ",");
-			for (j = 0; j < idnum; j++) {
-				pr_debug("found event %s\n", ids[j]);
-				/*
-				 * Duration time maps to a software event and can make
-				 * groups not count. Always use it outside a
-				 * group.
-				 */
-				if (!strcmp(ids[j], "duration_time")) {
-					if (j > 0)
-						strbuf_addf(events, "}:W,");
-					strbuf_addf(events, "duration_time");
-					no_group = true;
-					continue;
-				}
-				strbuf_addf(events, "%s%s",
-					j == 0 || no_group ? "{" : ",",
-					ids[j]);
-				no_group = false;
-			}
-			if (!no_group)
-				strbuf_addf(events, "}:W");
+
+			if (metricgroup__has_constraint(pe))
+				metricgroup__add_metric_non_group(events, ids, idnum);
+			else
+				metricgroup__add_metric_weak_group(events, ids, idnum);
 
 			eg = malloc(sizeof(struct egroup));
 			if (!eg) {
@@ -493,6 +561,10 @@ static int metricgroup__add_metric_list(const char *list, struct strbuf *events,
 		}
 	}
 	free(nlist);
+
+	if (!ret)
+		metricgroup___watchdog_constraint_hint(NULL, true);
+
 	return ret;
 }