Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1244 insertions, 0 deletions

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
new file mode 100644
index 000000000..060454a17
--- /dev/null
+++ b/tools/perf/util/metricgroup.c
@@ -0,0 +1,1244 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2017, Intel Corporation.
+ */
+
+/* Manage metrics and groups of metrics from JSON files */
+
+#include "metricgroup.h"
+#include "debug.h"
+#include "evlist.h"
+#include "evsel.h"
+#include "strbuf.h"
+#include "pmu.h"
+#include "expr.h"
+#include "rblist.h"
+#include <string.h>
+#include <errno.h>
+#include "strlist.h"
+#include <assert.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/zalloc.h>
+#include <subcmd/parse-options.h>
+#include <api/fs/fs.h>
+#include "util.h"
+#include <asm/bug.h>
+#include "cgroup.h"
+
+struct metric_event *metricgroup__lookup(struct rblist *metric_events,
+					 struct evsel *evsel,
+					 bool create)
+{
+	struct rb_node *nd;
+	struct metric_event me = {
+		.evsel = evsel
+	};
+
+	if (!metric_events)
+		return NULL;
+
+	nd = rblist__find(metric_events, &me);
+	if (nd)
+		return container_of(nd, struct metric_event, nd);
+	if (create) {
+		rblist__add_node(metric_events, &me);
+		nd = rblist__find(metric_events, &me);
+		if (nd)
+			return container_of(nd, struct metric_event, nd);
+	}
+	return NULL;
+}
+
+static int metric_event_cmp(struct rb_node *rb_node, const void *entry)
+{
+	struct metric_event *a = container_of(rb_node,
+					      struct metric_event,
+					      nd);
+	const struct metric_event *b = entry;
+
+	if (a->evsel == b->evsel)
+		return 0;
+	if ((char *)a->evsel < (char *)b->evsel)
+		return -1;
+	return +1;
+}
+
+static struct rb_node *metric_event_new(struct rblist *rblist __maybe_unused,
+					const void *entry)
+{
+	struct metric_event *me = malloc(sizeof(struct metric_event));
+
+	if (!me)
+		return NULL;
+	memcpy(me, entry, sizeof(struct metric_event));
+	me->evsel = ((struct metric_event *)entry)->evsel;
+	INIT_LIST_HEAD(&me->head);
+	return &me->nd;
+}
+
+static void metric_event_delete(struct rblist *rblist __maybe_unused,
+				struct rb_node *rb_node)
+{
+	struct metric_event *me = container_of(rb_node, struct metric_event, nd);
+	struct metric_expr *expr, *tmp;
+
+	list_for_each_entry_safe(expr, tmp, &me->head, nd) {
+		free(expr->metric_refs);
+		free(expr->metric_events);
+		free(expr);
+	}
+
+	free(me);
+}
+
+static void metricgroup__rblist_init(struct rblist *metric_events)
+{
+	rblist__init(metric_events);
+	metric_events->node_cmp = metric_event_cmp;
+	metric_events->node_new = metric_event_new;
+	metric_events->node_delete = metric_event_delete;
+}
+
+void metricgroup__rblist_exit(struct rblist *metric_events)
+{
+	rblist__exit(metric_events);
+}
+
+/*
+ * A node in the list of referenced metrics. metric_expr
+ * is held as a convenience to avoid a search through the
+ * metric list.
+ */
+struct metric_ref_node {
+	const char *metric_name;
+	const char *metric_expr;
+	struct list_head list;
+};
+
+struct metric {
+	struct list_head nd;
+	struct expr_parse_ctx pctx;
+	const char *metric_name;
+	const char *metric_expr;
+	const char *metric_unit;
+	struct list_head metric_refs;
+	int metric_refs_cnt;
+	int runtime;
+	bool has_constraint;
+};
+
+#define RECURSION_ID_MAX 1000
+
+struct expr_ids {
+	struct expr_id	id[RECURSION_ID_MAX];
+	int		cnt;
+};
+
+static struct expr_id *expr_ids__alloc(struct expr_ids *ids)
+{
+	if (ids->cnt >= RECURSION_ID_MAX)
+		return NULL;
+	return &ids->id[ids->cnt++];
+}
+
+static void expr_ids__exit(struct expr_ids *ids)
+{
+	int i;
+
+	for (i = 0; i < ids->cnt; i++)
+		free(ids->id[i].id);
+}
+
+static bool contains_event(struct evsel **metric_events, int num_events,
+			const char *event_name)
+{
+	int i;
+
+	for (i = 0; i < num_events; i++) {
+		if (!strcmp(metric_events[i]->name, event_name))
+			return true;
+	}
+	return false;
+}
+
+/**
+ * Find a group of events in perf_evlist that correspond to those from a parsed
+ * metric expression. Note, as find_evsel_group is called in the same order as
+ * perf_evlist was constructed, metric_no_merge doesn't need to test for
+ * underfilling a group.
+ * @perf_evlist: a list of events something like: {metric1 leader, metric1
+ * sibling, metric1 sibling}:W,duration_time,{metric2 leader, metric2 sibling,
+ * metric2 sibling}:W,duration_time
+ * @pctx: the parse context for the metric expression.
+ * @metric_no_merge: don't attempt to share events for the metric with other
+ * metrics.
+ * @has_constraint: is there a contraint on the group of events? In which case
+ * the events won't be grouped.
+ * @metric_events: out argument, null terminated array of evsel's associated
+ * with the metric.
+ * @evlist_used: in/out argument, bitmap tracking which evlist events are used.
+ * @return the first metric event or NULL on failure.
+ */
+static struct evsel *find_evsel_group(struct evlist *perf_evlist,
+				      struct expr_parse_ctx *pctx,
+				      bool metric_no_merge,
+				      bool has_constraint,
+				      struct evsel **metric_events,
+				      unsigned long *evlist_used)
+{
+	struct evsel *ev, *current_leader = NULL;
+	struct expr_id_data *val_ptr;
+	int i = 0, matched_events = 0, events_to_match;
+	const int idnum = (int)hashmap__size(&pctx->ids);
+
+	/*
+	 * duration_time is always grouped separately, when events are grouped
+	 * (ie has_constraint is false) then ignore it in the matching loop and
+	 * add it to metric_events at the end.
+	 */
+	if (!has_constraint &&
+	    hashmap__find(&pctx->ids, "duration_time", (void **)&val_ptr))
+		events_to_match = idnum - 1;
+	else
+		events_to_match = idnum;
+
+	evlist__for_each_entry (perf_evlist, ev) {
+		/*
+		 * Events with a constraint aren't grouped and match the first
+		 * events available.
+		 */
+		if (has_constraint && ev->weak_group)
+			continue;
+		/* Ignore event if already used and merging is disabled. */
+		if (metric_no_merge && test_bit(ev->idx, evlist_used))
+			continue;
+		if (!has_constraint && ev->leader != current_leader) {
+			/*
+			 * Start of a new group, discard the whole match and
+			 * start again.
+			 */
+			matched_events = 0;
+			memset(metric_events, 0,
+				sizeof(struct evsel *) * idnum);
+			current_leader = ev->leader;
+		}
+		/*
+		 * Check for duplicate events with the same name. For example,
+		 * uncore_imc/cas_count_read/ will turn into 6 events per socket
+		 * on skylakex. Only the first such event is placed in
+		 * metric_events. If events aren't grouped then this also
+		 * ensures that the same event in different sibling groups
+		 * aren't both added to metric_events.
+		 */
+		if (contains_event(metric_events, matched_events, ev->name))
+			continue;
+		/* Does this event belong to the parse context? */
+		if (hashmap__find(&pctx->ids, ev->name, (void **)&val_ptr))
+			metric_events[matched_events++] = ev;
+
+		if (matched_events == events_to_match)
+			break;
+	}
+
+	if (events_to_match != idnum) {
+		/* Add the first duration_time. */
+		evlist__for_each_entry(perf_evlist, ev) {
+			if (!strcmp(ev->name, "duration_time")) {
+				metric_events[matched_events++] = ev;
+				break;
+			}
+		}
+	}
+
+	if (matched_events != idnum) {
+		/* Not a whole match */
+		return NULL;
+	}
+
+	metric_events[idnum] = NULL;
+
+	for (i = 0; i < idnum; i++) {
+		ev = metric_events[i];
+		/* Don't free the used events. */
+		set_bit(ev->idx, evlist_used);
+		/*
+		 * The metric leader points to the identically named event in
+		 * metric_events.
+		 */
+		ev->metric_leader = ev;
+		/*
+		 * Mark two events with identical names in the same group (or
+		 * globally) as being in use as uncore events may be duplicated
+		 * for each pmu. Set the metric leader of such events to be the
+		 * event that appears in metric_events.
+		 */
+		evlist__for_each_entry_continue(perf_evlist, ev) {
+			/*
+			 * If events are grouped then the search can terminate
+			 * when then group is left.
+			 */
+			if (!has_constraint &&
+			    ev->leader != metric_events[i]->leader)
+				break;
+			if (!strcmp(metric_events[i]->name, ev->name)) {
+				set_bit(ev->idx, evlist_used);
+				ev->metric_leader = metric_events[i];
+			}
+		}
+	}
+
+	return metric_events[0];
+}
+
+static int metricgroup__setup_events(struct list_head *groups,
+				     bool metric_no_merge,
+				     struct evlist *perf_evlist,
+				     struct rblist *metric_events_list)
+{
+	struct metric_event *me;
+	struct metric_expr *expr;
+	int i = 0;
+	int ret = 0;
+	struct metric *m;
+	struct evsel *evsel, *tmp;
+	unsigned long *evlist_used;
+
+	evlist_used = bitmap_alloc(perf_evlist->core.nr_entries);
+	if (!evlist_used)
+		return -ENOMEM;
+
+	list_for_each_entry (m, groups, nd) {
+		struct evsel **metric_events;
+		struct metric_ref *metric_refs = NULL;
+
+		metric_events = calloc(sizeof(void *),
+				hashmap__size(&m->pctx.ids) + 1);
+		if (!metric_events) {
+			ret = -ENOMEM;
+			break;
+		}
+		evsel = find_evsel_group(perf_evlist, &m->pctx,
+					 metric_no_merge,
+					 m->has_constraint, metric_events,
+					 evlist_used);
+		if (!evsel) {
+			pr_debug("Cannot resolve %s: %s\n",
+					m->metric_name, m->metric_expr);
+			free(metric_events);
+			continue;
+		}
+		for (i = 0; metric_events[i]; i++)
+			metric_events[i]->collect_stat = true;
+		me = metricgroup__lookup(metric_events_list, evsel, true);
+		if (!me) {
+			ret = -ENOMEM;
+			free(metric_events);
+			break;
+		}
+		expr = malloc(sizeof(struct metric_expr));
+		if (!expr) {
+			ret = -ENOMEM;
+			free(metric_events);
+			break;
+		}
+
+		/*
+		 * Collect and store collected nested expressions
+		 * for metric processing.
+		 */
+		if (m->metric_refs_cnt) {
+			struct metric_ref_node *ref;
+
+			metric_refs = zalloc(sizeof(struct metric_ref) * (m->metric_refs_cnt + 1));
+			if (!metric_refs) {
+				ret = -ENOMEM;
+				free(metric_events);
+				free(expr);
+				break;
+			}
+
+			i = 0;
+			list_for_each_entry(ref, &m->metric_refs, list) {
+				/*
+				 * Intentionally passing just const char pointers,
+				 * originally from 'struct pmu_event' object.
+				 * We don't need to change them, so there's no
+				 * need to create our own copy.
+				 */
+				metric_refs[i].metric_name = ref->metric_name;
+				metric_refs[i].metric_expr = ref->metric_expr;
+				i++;
+			}
+		};
+
+		expr->metric_refs = metric_refs;
+		expr->metric_expr = m->metric_expr;
+		expr->metric_name = m->metric_name;
+		expr->metric_unit = m->metric_unit;
+		expr->metric_events = metric_events;
+		expr->runtime = m->runtime;
+		list_add(&expr->nd, &me->head);
+	}
+
+	evlist__for_each_entry_safe(perf_evlist, tmp, evsel) {
+		if (!test_bit(evsel->idx, evlist_used)) {
+			evlist__remove(perf_evlist, evsel);
+			evsel__delete(evsel);
+		}
+	}
+	bitmap_free(evlist_used);
+
+	return ret;
+}
+
+static bool match_metric(const char *n, const char *list)
+{
+	int len;
+	char *m;
+
+	if (!list)
+		return false;
+	if (!strcmp(list, "all"))
+		return true;
+	if (!n)
+		return !strcasecmp(list, "No_group");
+	len = strlen(list);
+	m = strcasestr(n, list);
+	if (!m)
+		return false;
+	if ((m == n || m[-1] == ';' || m[-1] == ' ') &&
+	    (m[len] == 0 || m[len] == ';'))
+		return true;
+	return false;
+}
+
+struct mep {
+	struct rb_node nd;
+	const char *name;
+	struct strlist *metrics;
+};
+
+static int mep_cmp(struct rb_node *rb_node, const void *entry)
+{
+	struct mep *a = container_of(rb_node, struct mep, nd);
+	struct mep *b = (struct mep *)entry;
+
+	return strcmp(a->name, b->name);
+}
+
+static struct rb_node *mep_new(struct rblist *rl __maybe_unused,
+					const void *entry)
+{
+	struct mep *me = malloc(sizeof(struct mep));
+
+	if (!me)
+		return NULL;
+	memcpy(me, entry, sizeof(struct mep));
+	me->name = strdup(me->name);
+	if (!me->name)
+		goto out_me;
+	me->metrics = strlist__new(NULL, NULL);
+	if (!me->metrics)
+		goto out_name;
+	return &me->nd;
+out_name:
+	zfree(&me->name);
+out_me:
+	free(me);
+	return NULL;
+}
+
+static struct mep *mep_lookup(struct rblist *groups, const char *name)
+{
+	struct rb_node *nd;
+	struct mep me = {
+		.name = name
+	};
+	nd = rblist__find(groups, &me);
+	if (nd)
+		return container_of(nd, struct mep, nd);
+	rblist__add_node(groups, &me);
+	nd = rblist__find(groups, &me);
+	if (nd)
+		return container_of(nd, struct mep, nd);
+	return NULL;
+}
+
+static void mep_delete(struct rblist *rl __maybe_unused,
+		       struct rb_node *nd)
+{
+	struct mep *me = container_of(nd, struct mep, nd);
+
+	strlist__delete(me->metrics);
+	zfree(&me->name);
+	free(me);
+}
+
+static void metricgroup__print_strlist(struct strlist *metrics, bool raw)
+{
+	struct str_node *sn;
+	int n = 0;
+
+	strlist__for_each_entry (sn, metrics) {
+		if (raw)
+			printf("%s%s", n > 0 ? " " : "", sn->s);
+		else
+			printf("  %s\n", sn->s);
+		n++;
+	}
+	if (raw)
+		putchar('\n');
+}
+
+void metricgroup__print(bool metrics, bool metricgroups, char *filter,
+			bool raw, bool details)
+{
+	struct pmu_events_map *map = perf_pmu__find_map(NULL);
+	struct pmu_event *pe;
+	int i;
+	struct rblist groups;
+	struct rb_node *node, *next;
+	struct strlist *metriclist = NULL;
+
+	if (!map)
+		return;
+
+	if (!metricgroups) {
+		metriclist = strlist__new(NULL, NULL);
+		if (!metriclist)
+			return;
+	}
+
+	rblist__init(&groups);
+	groups.node_new = mep_new;
+	groups.node_cmp = mep_cmp;
+	groups.node_delete = mep_delete;
+	for (i = 0; ; i++) {
+		const char *g;
+		pe = &map->table[i];
+
+		if (!pe->name && !pe->metric_group && !pe->metric_name)
+			break;
+		if (!pe->metric_expr)
+			continue;
+		g = pe->metric_group;
+		if (!g && pe->metric_name) {
+			if (pe->name)
+				continue;
+			g = "No_group";
+		}
+		if (g) {
+			char *omg;
+			char *mg = strdup(g);
+
+			if (!mg)
+				return;
+			omg = mg;
+			while ((g = strsep(&mg, ";")) != NULL) {
+				struct mep *me;
+				char *s;
+
+				g = skip_spaces(g);
+				if (*g == 0)
+					g = "No_group";
+				if (filter && !strstr(g, filter))
+					continue;
+				if (raw)
+					s = (char *)pe->metric_name;
+				else {
+					if (asprintf(&s, "%s\n%*s%s]",
+						     pe->metric_name, 8, "[", pe->desc) < 0)
+						return;
+
+					if (details) {
+						if (asprintf(&s, "%s\n%*s%s]",
+							     s, 8, "[", pe->metric_expr) < 0)
+							return;
+					}
+				}
+
+				if (!s)
+					continue;
+
+				if (!metricgroups) {
+					strlist__add(metriclist, s);
+				} else {
+					me = mep_lookup(&groups, g);
+					if (!me)
+						continue;
+					strlist__add(me->metrics, s);
+				}
+
+				if (!raw)
+					free(s);
+			}
+			free(omg);
+		}
+	}
+
+	if (!filter || !rblist__empty(&groups)) {
+		if (metricgroups && !raw)
+			printf("\nMetric Groups:\n\n");
+		else if (metrics && !raw)
+			printf("\nMetrics:\n\n");
+	}
+
+	for (node = rb_first_cached(&groups.entries); node; node = next) {
+		struct mep *me = container_of(node, struct mep, nd);
+
+		if (metricgroups)
+			printf("%s%s%s", me->name, metrics && !raw ? ":" : "", raw ? " " : "\n");
+		if (metrics)
+			metricgroup__print_strlist(me->metrics, raw);
+		next = rb_next(node);
+		rblist__remove_node(&groups, node);
+	}
+	if (!metricgroups)
+		metricgroup__print_strlist(metriclist, raw);
+	strlist__delete(metriclist);
+}
+
+static void metricgroup__add_metric_weak_group(struct strbuf *events,
+					       struct expr_parse_ctx *ctx)
+{
+	struct hashmap_entry *cur;
+	size_t bkt;
+	bool no_group = true, has_duration = false;
+
+	hashmap__for_each_entry((&ctx->ids), cur, bkt) {
+		pr_debug("found event %s\n", (const char *)cur->key);
+		/*
+		 * Duration time maps to a software event and can make
+		 * groups not count. Always use it outside a
+		 * group.
+		 */
+		if (!strcmp(cur->key, "duration_time")) {
+			has_duration = true;
+			continue;
+		}
+		strbuf_addf(events, "%s%s",
+			no_group ? "{" : ",",
+			(const char *)cur->key);
+		no_group = false;
+	}
+	if (!no_group) {
+		strbuf_addf(events, "}:W");
+		if (has_duration)
+			strbuf_addf(events, ",duration_time");
+	} else if (has_duration)
+		strbuf_addf(events, "duration_time");
+}
+
+static void metricgroup__add_metric_non_group(struct strbuf *events,
+					      struct expr_parse_ctx *ctx)
+{
+	struct hashmap_entry *cur;
+	size_t bkt;
+	bool first = true;
+
+	hashmap__for_each_entry((&ctx->ids), cur, bkt) {
+		if (!first)
+			strbuf_addf(events, ",");
+		strbuf_addf(events, "%s", (const char *)cur->key);
+		first = false;
+	}
+}
+
+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;
+}
+
+int __weak arch_get_runtimeparam(struct pmu_event *pe __maybe_unused)
+{
+	return 1;
+}
+
+static int __add_metric(struct list_head *metric_list,
+			struct pmu_event *pe,
+			bool metric_no_group,
+			int runtime,
+			struct metric **mp,
+			struct expr_id *parent,
+			struct expr_ids *ids)
+{
+	struct metric_ref_node *ref;
+	struct metric *m;
+
+	if (*mp == NULL) {
+		/*
+		 * We got in here for the parent group,
+		 * allocate it and put it on the list.
+		 */
+		m = zalloc(sizeof(*m));
+		if (!m)
+			return -ENOMEM;
+
+		expr__ctx_init(&m->pctx);
+		m->metric_name = pe->metric_name;
+		m->metric_expr = pe->metric_expr;
+		m->metric_unit = pe->unit;
+		m->runtime = runtime;
+		m->has_constraint = metric_no_group || metricgroup__has_constraint(pe);
+		INIT_LIST_HEAD(&m->metric_refs);
+		m->metric_refs_cnt = 0;
+
+		parent = expr_ids__alloc(ids);
+		if (!parent) {
+			free(m);
+			return -EINVAL;
+		}
+
+		parent->id = strdup(pe->metric_name);
+		if (!parent->id) {
+			free(m);
+			return -ENOMEM;
+		}
+		*mp = m;
+	} else {
+		/*
+		 * We got here for the referenced metric, via the
+		 * recursive metricgroup__add_metric call, add
+		 * it to the parent group.
+		 */
+		m = *mp;
+
+		ref = malloc(sizeof(*ref));
+		if (!ref)
+			return -ENOMEM;
+
+		/*
+		 * Intentionally passing just const char pointers,
+		 * from 'pe' object, so they never go away. We don't
+		 * need to change them, so there's no need to create
+		 * our own copy.
+		 */
+		ref->metric_name = pe->metric_name;
+		ref->metric_expr = pe->metric_expr;
+
+		list_add(&ref->list, &m->metric_refs);
+		m->metric_refs_cnt++;
+	}
+
+	/* Force all found IDs in metric to have us as parent ID. */
+	WARN_ON_ONCE(!parent);
+	m->pctx.parent = parent;
+
+	/*
+	 * For both the parent and referenced metrics, we parse
+	 * all the metric's IDs and add it to the parent context.
+	 */
+	if (expr__find_other(pe->metric_expr, NULL, &m->pctx, runtime) < 0) {
+		if (m->metric_refs_cnt == 0) {
+			expr__ctx_clear(&m->pctx);
+			free(m);
+			*mp = NULL;
+		}
+		return -EINVAL;
+	}
+
+	/*
+	 * We add new group only in the 'parent' call,
+	 * so bail out for referenced metric case.
+	 */
+	if (m->metric_refs_cnt)
+		return 0;
+
+	if (list_empty(metric_list))
+		list_add(&m->nd, metric_list);
+	else {
+		struct list_head *pos;
+
+		/* Place the largest groups at the front. */
+		list_for_each_prev(pos, metric_list) {
+			struct metric *old = list_entry(pos, struct metric, nd);
+
+			if (hashmap__size(&m->pctx.ids) <=
+			    hashmap__size(&old->pctx.ids))
+				break;
+		}
+		list_add(&m->nd, pos);
+	}
+
+	return 0;
+}
+
+#define map_for_each_event(__pe, __idx, __map)				\
+	for (__idx = 0, __pe = &__map->table[__idx];			\
+	     __pe->name || __pe->metric_group || __pe->metric_name;	\
+	     __pe = &__map->table[++__idx])
+
+#define map_for_each_metric(__pe, __idx, __map, __metric)		\
+	map_for_each_event(__pe, __idx, __map)				\
+		if (__pe->metric_expr &&				\
+		    (match_metric(__pe->metric_group, __metric) ||	\
+		     match_metric(__pe->metric_name, __metric)))
+
+static struct pmu_event *find_metric(const char *metric, struct pmu_events_map *map)
+{
+	struct pmu_event *pe;
+	int i;
+
+	map_for_each_event(pe, i, map) {
+		if (match_metric(pe->metric_name, metric))
+			return pe;
+	}
+
+	return NULL;
+}
+
+static int recursion_check(struct metric *m, const char *id, struct expr_id **parent,
+			   struct expr_ids *ids)
+{
+	struct expr_id_data *data;
+	struct expr_id *p;
+	int ret;
+
+	/*
+	 * We get the parent referenced by 'id' argument and
+	 * traverse through all the parent object IDs to check
+	 * if we already processed 'id', if we did, it's recursion
+	 * and we fail.
+	 */
+	ret = expr__get_id(&m->pctx, id, &data);
+	if (ret)
+		return ret;
+
+	p = data->parent;
+
+	while (p->parent) {
+		if (!strcmp(p->id, id)) {
+			pr_err("failed: recursion detected for %s\n", id);
+			return -1;
+		}
+		p = p->parent;
+	}
+
+	/*
+	 * If we are over the limit of static entris, the metric
+	 * is too difficult/nested to process, fail as well.
+	 */
+	p = expr_ids__alloc(ids);
+	if (!p) {
+		pr_err("failed: too many nested metrics\n");
+		return -EINVAL;
+	}
+
+	p->id     = strdup(id);
+	p->parent = data->parent;
+	*parent   = p;
+
+	return p->id ? 0 : -ENOMEM;
+}
+
+static int add_metric(struct list_head *metric_list,
+		      struct pmu_event *pe,
+		      bool metric_no_group,
+		      struct metric **mp,
+		      struct expr_id *parent,
+		      struct expr_ids *ids);
+
+static int __resolve_metric(struct metric *m,
+			    bool metric_no_group,
+			    struct list_head *metric_list,
+			    struct pmu_events_map *map,
+			    struct expr_ids *ids)
+{
+	struct hashmap_entry *cur;
+	size_t bkt;
+	bool all;
+	int ret;
+
+	/*
+	 * Iterate all the parsed IDs and if there's metric,
+	 * add it to the context.
+	 */
+	do {
+		all = true;
+		hashmap__for_each_entry((&m->pctx.ids), cur, bkt) {
+			struct expr_id *parent;
+			struct pmu_event *pe;
+
+			pe = find_metric(cur->key, map);
+			if (!pe)
+				continue;
+
+			ret = recursion_check(m, cur->key, &parent, ids);
+			if (ret)
+				return ret;
+
+			all = false;
+			/* The metric key itself needs to go out.. */
+			expr__del_id(&m->pctx, cur->key);
+
+			/* ... and it gets resolved to the parent context. */
+			ret = add_metric(metric_list, pe, metric_no_group, &m, parent, ids);
+			if (ret)
+				return ret;
+
+			/*
+			 * We added new metric to hashmap, so we need
+			 * to break the iteration and start over.
+			 */
+			break;
+		}
+	} while (!all);
+
+	return 0;
+}
+
+static int resolve_metric(bool metric_no_group,
+			  struct list_head *metric_list,
+			  struct pmu_events_map *map,
+			  struct expr_ids *ids)
+{
+	struct metric *m;
+	int err;
+
+	list_for_each_entry(m, metric_list, nd) {
+		err = __resolve_metric(m, metric_no_group, metric_list, map, ids);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+static int add_metric(struct list_head *metric_list,
+		      struct pmu_event *pe,
+		      bool metric_no_group,
+		      struct metric **m,
+		      struct expr_id *parent,
+		      struct expr_ids *ids)
+{
+	struct metric *orig = *m;
+	int ret = 0;
+
+	pr_debug("metric expr %s for %s\n", pe->metric_expr, pe->metric_name);
+
+	if (!strstr(pe->metric_expr, "?")) {
+		ret = __add_metric(metric_list, pe, metric_no_group, 1, m, parent, ids);
+	} else {
+		int j, count;
+
+		count = arch_get_runtimeparam(pe);
+
+		/* This loop is added to create multiple
+		 * events depend on count value and add
+		 * those events to metric_list.
+		 */
+
+		for (j = 0; j < count && !ret; j++, *m = orig)
+			ret = __add_metric(metric_list, pe, metric_no_group, j, m, parent, ids);
+	}
+
+	return ret;
+}
+
+static int metricgroup__add_metric(const char *metric, bool metric_no_group,
+				   struct strbuf *events,
+				   struct list_head *metric_list,
+				   struct pmu_events_map *map)
+{
+	struct expr_ids ids = { .cnt = 0, };
+	struct pmu_event *pe;
+	struct metric *m;
+	LIST_HEAD(list);
+	int i, ret;
+	bool has_match = false;
+
+	map_for_each_metric(pe, i, map, metric) {
+		has_match = true;
+		m = NULL;
+
+		ret = add_metric(&list, pe, metric_no_group, &m, NULL, &ids);
+		if (ret)
+			goto out;
+
+		/*
+		 * Process any possible referenced metrics
+		 * included in the expression.
+		 */
+		ret = resolve_metric(metric_no_group,
+				     &list, map, &ids);
+		if (ret)
+			goto out;
+	}
+
+	/* End of pmu events. */
+	if (!has_match) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	list_for_each_entry(m, &list, nd) {
+		if (events->len > 0)
+			strbuf_addf(events, ",");
+
+		if (m->has_constraint) {
+			metricgroup__add_metric_non_group(events,
+							  &m->pctx);
+		} else {
+			metricgroup__add_metric_weak_group(events,
+							   &m->pctx);
+		}
+	}
+
+out:
+	/*
+	 * add to metric_list so that they can be released
+	 * even if it's failed
+	 */
+	list_splice(&list, metric_list);
+	expr_ids__exit(&ids);
+	return ret;
+}
+
+static int metricgroup__add_metric_list(const char *list, bool metric_no_group,
+					struct strbuf *events,
+					struct list_head *metric_list,
+					struct pmu_events_map *map)
+{
+	char *llist, *nlist, *p;
+	int ret = -EINVAL;
+
+	nlist = strdup(list);
+	if (!nlist)
+		return -ENOMEM;
+	llist = nlist;
+
+	strbuf_init(events, 100);
+	strbuf_addf(events, "%s", "");
+
+	while ((p = strsep(&llist, ",")) != NULL) {
+		ret = metricgroup__add_metric(p, metric_no_group, events,
+					      metric_list, map);
+		if (ret == -EINVAL) {
+			fprintf(stderr, "Cannot find metric or group `%s'\n",
+					p);
+			break;
+		}
+	}
+	free(nlist);
+
+	if (!ret)
+		metricgroup___watchdog_constraint_hint(NULL, true);
+
+	return ret;
+}
+
+static void metric__free_refs(struct metric *metric)
+{
+	struct metric_ref_node *ref, *tmp;
+
+	list_for_each_entry_safe(ref, tmp, &metric->metric_refs, list) {
+		list_del(&ref->list);
+		free(ref);
+	}
+}
+
+static void metricgroup__free_metrics(struct list_head *metric_list)
+{
+	struct metric *m, *tmp;
+
+	list_for_each_entry_safe (m, tmp, metric_list, nd) {
+		metric__free_refs(m);
+		expr__ctx_clear(&m->pctx);
+		list_del_init(&m->nd);
+		free(m);
+	}
+}
+
+static int parse_groups(struct evlist *perf_evlist, const char *str,
+			bool metric_no_group,
+			bool metric_no_merge,
+			struct perf_pmu *fake_pmu,
+			struct rblist *metric_events,
+			struct pmu_events_map *map)
+{
+	struct parse_events_error parse_error;
+	struct strbuf extra_events;
+	LIST_HEAD(metric_list);
+	int ret;
+
+	if (metric_events->nr_entries == 0)
+		metricgroup__rblist_init(metric_events);
+	ret = metricgroup__add_metric_list(str, metric_no_group,
+					   &extra_events, &metric_list, map);
+	if (ret)
+		goto out;
+	pr_debug("adding %s\n", extra_events.buf);
+	bzero(&parse_error, sizeof(parse_error));
+	ret = __parse_events(perf_evlist, extra_events.buf, &parse_error, fake_pmu);
+	if (ret) {
+		parse_events_print_error(&parse_error, extra_events.buf);
+		goto out;
+	}
+	ret = metricgroup__setup_events(&metric_list, metric_no_merge,
+					perf_evlist, metric_events);
+out:
+	metricgroup__free_metrics(&metric_list);
+	strbuf_release(&extra_events);
+	return ret;
+}
+
+int metricgroup__parse_groups(const struct option *opt,
+			      const char *str,
+			      bool metric_no_group,
+			      bool metric_no_merge,
+			      struct rblist *metric_events)
+{
+	struct evlist *perf_evlist = *(struct evlist **)opt->value;
+	struct pmu_events_map *map = perf_pmu__find_map(NULL);
+
+	if (!map)
+		return 0;
+
+	return parse_groups(perf_evlist, str, metric_no_group,
+			    metric_no_merge, NULL, metric_events, map);
+}
+
+int metricgroup__parse_groups_test(struct evlist *evlist,
+				   struct pmu_events_map *map,
+				   const char *str,
+				   bool metric_no_group,
+				   bool metric_no_merge,
+				   struct rblist *metric_events)
+{
+	return parse_groups(evlist, str, metric_no_group,
+			    metric_no_merge, &perf_pmu__fake, metric_events, map);
+}
+
+bool metricgroup__has_metric(const char *metric)
+{
+	struct pmu_events_map *map = perf_pmu__find_map(NULL);
+	struct pmu_event *pe;
+	int i;
+
+	if (!map)
+		return false;
+
+	for (i = 0; ; i++) {
+		pe = &map->table[i];
+
+		if (!pe->name && !pe->metric_group && !pe->metric_name)
+			break;
+		if (!pe->metric_expr)
+			continue;
+		if (match_metric(pe->metric_name, metric))
+			return true;
+	}
+	return false;
+}
+
+int metricgroup__copy_metric_events(struct evlist *evlist, struct cgroup *cgrp,
+				    struct rblist *new_metric_events,
+				    struct rblist *old_metric_events)
+{
+	unsigned i;
+
+	for (i = 0; i < rblist__nr_entries(old_metric_events); i++) {
+		struct rb_node *nd;
+		struct metric_event *old_me, *new_me;
+		struct metric_expr *old_expr, *new_expr;
+		struct evsel *evsel;
+		size_t alloc_size;
+		int idx, nr;
+
+		nd = rblist__entry(old_metric_events, i);
+		old_me = container_of(nd, struct metric_event, nd);
+
+		evsel = evlist__find_evsel(evlist, old_me->evsel->idx);
+		if (!evsel)
+			return -EINVAL;
+		new_me = metricgroup__lookup(new_metric_events, evsel, true);
+		if (!new_me)
+			return -ENOMEM;
+
+		pr_debug("copying metric event for cgroup '%s': %s (idx=%d)\n",
+			 cgrp ? cgrp->name : "root", evsel->name, evsel->idx);
+
+		list_for_each_entry(old_expr, &old_me->head, nd) {
+			new_expr = malloc(sizeof(*new_expr));
+			if (!new_expr)
+				return -ENOMEM;
+
+			new_expr->metric_expr = old_expr->metric_expr;
+			new_expr->metric_name = old_expr->metric_name;
+			new_expr->metric_unit = old_expr->metric_unit;
+			new_expr->runtime = old_expr->runtime;
+
+			if (old_expr->metric_refs) {
+				/* calculate number of metric_events */
+				for (nr = 0; old_expr->metric_refs[nr].metric_name; nr++)
+					continue;
+				alloc_size = sizeof(*new_expr->metric_refs);
+				new_expr->metric_refs = calloc(nr + 1, alloc_size);
+				if (!new_expr->metric_refs) {
+					free(new_expr);
+					return -ENOMEM;
+				}
+
+				memcpy(new_expr->metric_refs, old_expr->metric_refs,
+				       nr * alloc_size);
+			} else {
+				new_expr->metric_refs = NULL;
+			}
+
+			/* calculate number of metric_events */
+			for (nr = 0; old_expr->metric_events[nr]; nr++)
+				continue;
+			alloc_size = sizeof(*new_expr->metric_events);
+			new_expr->metric_events = calloc(nr + 1, alloc_size);
+			if (!new_expr->metric_events) {
+				free(new_expr->metric_refs);
+				free(new_expr);
+				return -ENOMEM;
+			}
+
+			/* copy evsel in the same position */
+			for (idx = 0; idx < nr; idx++) {
+				evsel = old_expr->metric_events[idx];
+				evsel = evlist__find_evsel(evlist, evsel->idx);
+				if (evsel == NULL) {
+					free(new_expr->metric_events);
+					free(new_expr->metric_refs);
+					free(new_expr);
+					return -EINVAL;
+				}
+				new_expr->metric_events[idx] = evsel;
+			}
+
+			list_add(&new_expr->nd, &new_me->head);
+		}
+	}
+	return 0;
+}