1 files changed, 81 insertions, 36 deletions

diff --git a/tools/perf/arch/x86/util/topdown.c b/tools/perf/arch/x86/util/topdown.c
index 2f3d96aa92a5..bafd285119d7 100644
--- a/tools/perf/arch/x86/util/topdown.c
+++ b/tools/perf/arch/x86/util/topdown.c
@@ -1,63 +1,108 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <stdio.h>
-#include "api/fs/fs.h"
+#include <errno.h>
+#include "util/evlist.h"
 #include "util/pmu.h"
+#include "util/pmus.h"
 #include "util/topdown.h"
+#include "topdown.h"
+#include "evsel.h"
 
-/*
- * Check whether we can use a group for top down.
- * Without a group may get bad results due to multiplexing.
- */
-bool arch_topdown_check_group(bool *warn)
+// cmask=0, inv=0, pc=0, edge=0, umask=4, event=0
+#define TOPDOWN_SLOTS		0x0400
+
+/* Check whether there is a PMU which supports the perf metrics. */
+bool topdown_sys_has_perf_metrics(void)
 {
-	int n;
+	static bool has_perf_metrics;
+	static bool cached;
+	struct perf_pmu *pmu;
 
-	if (sysctl__read_int("kernel/nmi_watchdog", &n) < 0)
-		return false;
-	if (n > 0) {
-		*warn = true;
-		return false;
-	}
-	return true;
+	if (cached)
+		return has_perf_metrics;
+
+	/*
+	 * The perf metrics feature is a core PMU feature.
+	 * The PERF_TYPE_RAW type is the type of a core PMU.
+	 * The slots event is only available when the core PMU
+	 * supports the perf metrics feature.
+	 */
+	pmu = perf_pmus__find_by_type(PERF_TYPE_RAW);
+	if (pmu && perf_pmu__have_event(pmu, "slots"))
+		has_perf_metrics = true;
+
+	cached = true;
+	return has_perf_metrics;
 }
 
-void arch_topdown_group_warn(void)
+bool arch_is_topdown_slots(const struct evsel *evsel)
 {
-	fprintf(stderr,
-		"nmi_watchdog enabled with topdown. May give wrong results.\n"
-		"Disable with echo 0 > /proc/sys/kernel/nmi_watchdog\n");
+	return evsel->core.attr.type == PERF_TYPE_RAW &&
+	       evsel->core.attr.config == TOPDOWN_SLOTS &&
+	       evsel->core.attr.config1 == 0;
 }
 
-#define TOPDOWN_SLOTS		0x0400
+bool arch_is_topdown_metrics(const struct evsel *evsel)
+{
+	// cmask=0, inv=0, pc=0, edge=0, umask=0x80-0x87, event=0
+	return evsel->core.attr.type == PERF_TYPE_RAW &&
+		(evsel->core.attr.config & 0xFFFFF8FF) == 0x8000 &&
+		evsel->core.attr.config1 == 0;
+}
 
-static bool is_topdown_slots_event(struct evsel *counter)
+/*
+ * Check whether a topdown group supports sample-read.
+ *
+ * Only Topdown metric supports sample-read. The slots
+ * event must be the leader of the topdown group.
+ */
+bool arch_topdown_sample_read(struct evsel *leader)
 {
-	if (!counter->pmu_name)
+	struct evsel *evsel;
+
+	if (!evsel__sys_has_perf_metrics(leader))
 		return false;
 
-	if (strcmp(counter->pmu_name, "cpu"))
+	if (!arch_is_topdown_slots(leader))
 		return false;
 
-	if (counter->core.attr.config == TOPDOWN_SLOTS)
-		return true;
+	/*
+	 * If slots event as leader event but no topdown metric events
+	 * in group, slots event should still sample as leader.
+	 */
+	evlist__for_each_entry(leader->evlist, evsel) {
+		if (evsel->core.leader != leader->core.leader)
+			continue;
+		if (evsel != leader && arch_is_topdown_metrics(evsel))
+			return true;
+	}
 
 	return false;
 }
 
 /*
- * Check whether a topdown group supports sample-read.
- *
- * Only Topdown metic supports sample-read. The slots
- * event must be the leader of the topdown group.
+ * Make a copy of the topdown metric event metric_event with the given index but
+ * change its configuration to be a topdown slots event. Copying from
+ * metric_event ensures modifiers are the same.
  */
-
-bool arch_topdown_sample_read(struct evsel *leader)
+int topdown_insert_slots_event(struct list_head *list, int idx, struct evsel *metric_event)
 {
-	if (!pmu_have_event("cpu", "slots"))
-		return false;
+	struct evsel *evsel = evsel__new_idx(&metric_event->core.attr, idx);
 
-	if (is_topdown_slots_event(leader))
-		return true;
+	if (!evsel)
+		return -ENOMEM;
 
-	return false;
+	evsel->core.attr.config = TOPDOWN_SLOTS;
+	evsel->core.cpus = perf_cpu_map__get(metric_event->core.cpus);
+	evsel->core.pmu_cpus = perf_cpu_map__get(metric_event->core.pmu_cpus);
+	evsel->core.is_pmu_core = true;
+	evsel->pmu = metric_event->pmu;
+	evsel->name = strdup("slots");
+	evsel->precise_max = metric_event->precise_max;
+	evsel->sample_read = metric_event->sample_read;
+	evsel->weak_group = metric_event->weak_group;
+	evsel->bpf_counter = metric_event->bpf_counter;
+	evsel->retire_lat = metric_event->retire_lat;
+	evsel__set_leader(evsel, evsel__leader(metric_event));
+	list_add_tail(&evsel->core.node, list);
+	return 0;
 }