// 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;
}

static bool evsel_same_pmu_or_none(struct evsel *ev1, struct evsel *ev2)
{
        if (!ev1->pmu_name || !ev2->pmu_name)
                return true;

        return !strcmp(ev1->pmu_name, ev2->pmu_name);
}

/**
 * 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 constraint 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->core.idx, evlist_used))
                        continue;
                if (!has_constraint && !evsel__has_leader(ev, 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 = evsel__leader(ev);
                }
                /*
                 * 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->core.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->core.leader != metric_events[i]->core.leader &&
                            evsel_same_pmu_or_none(evsel__leader(ev), evsel__leader(metric_events[i])))
                                break;
                        if (!strcmp(metric_events[i]->name, ev->name)) {
                                set_bit(ev->core.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->core.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;
}

static bool match_pe_metric(struct pmu_event *pe, const char *metric)
{
        return match_metric(pe->metric_group, metric) ||
               match_metric(pe->metric_name, metric);
}

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');
}

static int metricgroup__print_pmu_event(struct pmu_event *pe,
                                        bool metricgroups, char *filter,
                                        bool raw, bool details,
                                        struct rblist *groups,
                                        struct strlist *metriclist)
{
        const char *g;
        char *omg, *mg;

        g = pe->metric_group;
        if (!g && pe->metric_name) {
                if (pe->name)
                        return 0;
                g = "No_group";
        }

        if (!g)
                return 0;

        mg = strdup(g);

        if (!mg)
                return -ENOMEM;
        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 -1;
                        if (details) {
                                if (asprintf(&s, "%s\n%*s%s]",
                                             s, 8, "[", pe->metric_expr) < 0)
                                        return -1;
                        }
                }

                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);

        return 0;
}

struct metricgroup_print_sys_idata {
        struct strlist *metriclist;
        char *filter;
        struct rblist *groups;
        bool metricgroups;
        bool raw;
        bool details;
};

typedef int (*metricgroup_sys_event_iter_fn)(struct pmu_event *pe, void *);

struct metricgroup_iter_data {
        metricgroup_sys_event_iter_fn fn;
        void *data;
};

static int metricgroup__sys_event_iter(struct pmu_event *pe, void *data)
{
        struct metricgroup_iter_data *d = data;
        struct perf_pmu *pmu = NULL;

        if (!pe->metric_expr || !pe->compat)
                return 0;

        while ((pmu = perf_pmu__scan(pmu))) {

                if (!pmu->id || strcmp(pmu->id, pe->compat))
                        continue;

                return d->fn(pe, d->data);
        }

        return 0;
}

static int metricgroup__print_sys_event_iter(struct pmu_event *pe, void *data)
{
        struct metricgroup_print_sys_idata *d = data;

        return metricgroup__print_pmu_event(pe, d->metricgroups, d->filter, d->raw,
                                     d->details, d->groups, d->metriclist);
}

void metricgroup__print(bool metrics, bool metricgroups, char *filter,
                        bool raw, bool details)
{
        struct pmu_events_map *map = pmu_events_map__find();
        struct pmu_event *pe;
        int i;
        struct rblist groups;
        struct rb_node *node, *next;
        struct strlist *metriclist = NULL;

        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; map; i++) {
                pe = &map->table[i];

                if (!pe->name && !pe->metric_group && !pe->metric_name)
                        break;
                if (!pe->metric_expr)
                        continue;
                if (metricgroup__print_pmu_event(pe, metricgroups, filter,
                                                 raw, details, &groups,
                                                 metriclist) < 0)
                        return;
        }

        {
                struct metricgroup_iter_data data = {
                        .fn = metricgroup__print_sys_event_iter,
                        .data = (void *) &(struct metricgroup_print_sys_idata){
                                .metriclist = metriclist,
                                .metricgroups = metricgroups,
                                .filter = filter,
                                .raw = raw,
                                .details = details,
                                .groups = &groups,
                        },
                };

                pmu_for_each_sys_event(metricgroup__sys_event_iter, &data);
        }

        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;
}

struct metricgroup_add_iter_data {
        struct list_head *metric_list;
        const char *metric;
        struct expr_ids *ids;
        int *ret;
        bool *has_match;
        bool metric_no_group;
};

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)                                  \
        if (__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)))

struct pmu_event *metricgroup__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 = expr_id_data__parent(data);

        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 = expr_id_data__parent(data);
        *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 = metricgroup__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_sys_event_iter(struct pmu_event *pe,
                                                  void *data)
{
        struct metricgroup_add_iter_data *d = data;
        struct metric *m = NULL;
        int ret;

        if (!match_pe_metric(pe, d->metric))
                return 0;

        ret = add_metric(d->metric_list, pe, d->metric_no_group, &m, NULL, d->ids);
        if (ret)
                goto out;

        ret = resolve_metric(d->metric_no_group,
                                     d->metric_list, NULL, d->ids);
        if (ret)
                goto out;

        *(d->has_match) = true;

out:
        *(d->ret) = ret;
        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;
        }

        {
                struct metricgroup_iter_data data = {
                        .fn = metricgroup__add_metric_sys_event_iter,
                        .data = (void *) &(struct metricgroup_add_iter_data) {
                                .metric_list = &list,
                                .metric = metric,
                                .metric_no_group = metric_no_group,
                                .ids = &ids,
                                .has_match = &has_match,
                                .ret = &ret,
                        },
                };

                pmu_for_each_sys_event(metricgroup__sys_event_iter, &data);
        }
        /* 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 = pmu_events_map__find();

        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 = pmu_events_map__find();
        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->core.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->core.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->core.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;
}