// 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 "pmus.h"
#include "print-events.h"
#include "smt.h"
#include "tool_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/list_sort.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include <perf/cpumap.h>
#include <subcmd/parse-options.h>
#include <api/fs/fs.h>
#include "util.h"
#include <asm/bug.h>
#include "cgroup.h"
#include "util/hashmap.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;

        if (evsel && evsel->metric_leader)
                me.evsel = evsel->metric_leader;
        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;
        me->is_default = false;
        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) {
                zfree(&expr->metric_name);
                zfree(&expr->metric_refs);
                zfree(&expr->metric_events);
                free(expr);
        }

        free(me);
}

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);
}

/**
 * The metric under construction. The data held here will be placed in a
 * metric_expr.
 */
struct metric {
        struct list_head nd;
        /**
         * The expression parse context importantly holding the IDs contained
         * within the expression.
         */
        struct expr_parse_ctx *pctx;
        const char *pmu;
        /** The name of the metric such as "IPC". */
        const char *metric_name;
        /** Modifier on the metric such as "u" or NULL for none. */
        const char *modifier;
        /** The expression to parse, for example, "instructions/cycles". */
        const char *metric_expr;
        /** Optional threshold expression where zero value is green, otherwise red. */
        const char *metric_threshold;
        /**
         * The "ScaleUnit" that scales and adds a unit to the metric during
         * output.
         */
        const char *metric_unit;
        /**
         * Optional name of the metric group reported
         * if the Default metric group is being processed.
         */
        const char *default_metricgroup_name;
        /** Optional null terminated array of referenced metrics. */
        struct metric_ref *metric_refs;
        /**
         * Should events of the metric be grouped?
         */
        bool group_events;
        /** Show events even if in the Default metric group. */
        bool default_show_events;
        /**
         * Parsed events for the metric. Optional as events may be taken from a
         * different metric whose group contains all the IDs necessary for this
         * one.
         */
        struct evlist *evlist;
};

static void metric__watchdog_constraint_hint(const char *name, bool foot)
{
        static bool violate_nmi_constraint;

        if (!foot) {
                pr_warning("Not grouping metric %s's events.\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 metric__group_events(const struct pmu_metric *pm, bool metric_no_threshold)
{
        switch (pm->event_grouping) {
        case MetricNoGroupEvents:
                return false;
        case MetricNoGroupEventsNmi:
                if (!sysctl__nmi_watchdog_enabled())
                        return true;
                metric__watchdog_constraint_hint(pm->metric_name, /*foot=*/false);
                return false;
        case MetricNoGroupEventsSmt:
                return !smt_on();
        case MetricNoGroupEventsThresholdAndNmi:
                if (metric_no_threshold)
                        return true;
                if (!sysctl__nmi_watchdog_enabled())
                        return true;
                metric__watchdog_constraint_hint(pm->metric_name, /*foot=*/false);
                return false;
        case MetricGroupEvents:
        default:
                return true;
        }
}

static void metric__free(struct metric *m)
{
        if (!m)
                return;

        zfree(&m->metric_refs);
        expr__ctx_free(m->pctx);
        zfree(&m->modifier);
        evlist__delete(m->evlist);
        free(m);
}

static struct metric *metric__new(const struct pmu_metric *pm,
                                  const char *modifier,
                                  bool metric_no_group,
                                  bool metric_no_threshold,
                                  int runtime,
                                  const char *user_requested_cpu_list,
                                  bool system_wide)
{
        struct metric *m;

        m = zalloc(sizeof(*m));
        if (!m)
                return NULL;

        m->pctx = expr__ctx_new();
        if (!m->pctx)
                goto out_err;

        m->pmu = pm->pmu ?: "cpu";
        m->metric_name = pm->metric_name;
        m->default_metricgroup_name = pm->default_metricgroup_name ?: "";
        m->modifier = NULL;
        if (modifier) {
                m->modifier = strdup(modifier);
                if (!m->modifier)
                        goto out_err;
        }
        m->metric_expr = pm->metric_expr;
        m->metric_threshold = pm->metric_threshold;
        m->metric_unit = pm->unit;
        m->pctx->sctx.user_requested_cpu_list = NULL;
        if (user_requested_cpu_list) {
                m->pctx->sctx.user_requested_cpu_list = strdup(user_requested_cpu_list);
                if (!m->pctx->sctx.user_requested_cpu_list)
                        goto out_err;
        }
        m->pctx->sctx.runtime = runtime;
        m->pctx->sctx.system_wide = system_wide;
        m->group_events = !metric_no_group && metric__group_events(pm, metric_no_threshold);
        m->default_show_events = pm->default_show_events;
        m->metric_refs = NULL;
        m->evlist = NULL;

        return m;
out_err:
        metric__free(m);
        return NULL;
}

static bool contains_metric_id(struct evsel **metric_events, int num_events,
                               const char *metric_id)
{
        int i;

        for (i = 0; i < num_events; i++) {
                if (!strcmp(evsel__metric_id(metric_events[i]), metric_id))
                        return true;
        }
        return false;
}

/**
 * setup_metric_events - Find a group of events in metric_evlist that correspond
 *                       to the IDs from a parsed metric expression.
 * @pmu: The PMU for the IDs.
 * @ids: the metric IDs to match.
 * @metric_evlist: the list of perf events.
 * @out_metric_events: holds the created metric events array.
 */
static int setup_metric_events(const char *pmu, struct hashmap *ids,
                               struct evlist *metric_evlist,
                               struct evsel ***out_metric_events)
{
        struct evsel **metric_events;
        const char *metric_id;
        struct evsel *ev;
        size_t ids_size, matched_events, i;
        bool all_pmus = !strcmp(pmu, "all") || perf_pmus__num_core_pmus() == 1 || !is_pmu_core(pmu);

        *out_metric_events = NULL;
        ids_size = hashmap__size(ids);

        metric_events = calloc(ids_size + 1, sizeof(void *));
        if (!metric_events)
                return -ENOMEM;

        matched_events = 0;
        evlist__for_each_entry(metric_evlist, ev) {
                struct expr_id_data *val_ptr;

                /* Don't match events for the wrong hybrid PMU. */
                if (!all_pmus && ev->pmu && evsel__is_hybrid(ev) &&
                    strcmp(ev->pmu->name, pmu))
                        continue;
                /*
                 * 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.
                 */
                metric_id = evsel__metric_id(ev);
                if (contains_metric_id(metric_events, matched_events, metric_id))
                        continue;
                /*
                 * Does this event belong to the parse context? For
                 * combined or shared groups, this metric may not care
                 * about this event.
                 */
                if (hashmap__find(ids, metric_id, &val_ptr)) {
                        pr_debug("Matched metric-id %s to %s\n", metric_id, evsel__name(ev));
                        metric_events[matched_events++] = ev;

                        if (matched_events >= ids_size)
                                break;
                }
        }
        if (matched_events < ids_size) {
                free(metric_events);
                return -EINVAL;
        }
        for (i = 0; i < ids_size; i++) {
                ev = metric_events[i];
                ev->collect_stat = true;

                /*
                 * 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.
                 */
                metric_id = evsel__metric_id(ev);
                evlist__for_each_entry_continue(metric_evlist, ev) {
                        if (!strcmp(evsel__metric_id(ev), metric_id))
                                ev->metric_leader = metric_events[i];
                }
        }
        *out_metric_events = metric_events;
        return 0;
}

static bool match_metric_or_groups(const char *metric_or_groups, const char *sought)
{
        int len;
        const char *m;

        if (!sought)
                return false;
        if (!strcmp(sought, "all"))
                return true;
        if (!metric_or_groups)
                return !strcasecmp(sought, "No_group");
        len = strlen(sought);
        if (!strncasecmp(metric_or_groups, sought, len) &&
            (metric_or_groups[len] == 0 || metric_or_groups[len] == ';'))
                return true;
        m = strchr(metric_or_groups, ';');
        return m && match_metric_or_groups(m + 1, sought);
}

static bool match_pm_metric_or_groups(const struct pmu_metric *pm, const char *pmu,
                                      const char *metric_or_groups)
{
        const char *pm_pmu = pm->pmu ?: "cpu";

        if (strcmp(pmu, "all") && strcmp(pm_pmu, pmu))
                return false;

        return match_metric_or_groups(pm->metric_group, metric_or_groups) ||
               match_metric_or_groups(pm->metric_name, metric_or_groups);
}

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

static int metricgroup__sys_event_iter(const struct pmu_metric *pm,
                                       const struct pmu_metrics_table *table,
                                       void *data)
{
        struct metricgroup_iter_data *d = data;
        struct perf_pmu *pmu = NULL;

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

        while ((pmu = perf_pmus__scan(pmu))) {

                if (!pmu->id || !pmu_uncore_identifier_match(pm->compat, pmu->id))
                        continue;

                return d->fn(pm, table, d->data);
        }
        return 0;
}

int metricgroup__for_each_metric(const struct pmu_metrics_table *table, pmu_metric_iter_fn fn,
                                 void *data)
{
        struct metricgroup_iter_data sys_data = {
                .fn = fn,
                .data = data,
        };
        const struct pmu_metrics_table *tables[2] = {
                table,
                pmu_metrics_table__default(),
        };

        for (size_t i = 0; i < ARRAY_SIZE(tables); i++) {
                int ret;

                if (!tables[i])
                        continue;

                ret = pmu_metrics_table__for_each_metric(tables[i], fn, data);
                if (ret)
                        return ret;
        }

        return pmu_for_each_sys_metric(metricgroup__sys_event_iter, &sys_data);
}

static const char *code_characters = ",-=@";

static int encode_metric_id(struct strbuf *sb, const char *x)
{
        int ret = 0;

        for (; *x; x++) {
                const char *c = strchr(code_characters, *x);
                if (c) {
                        ret = strbuf_addch(sb, '!');
                        if (ret)
                                break;

                        ret = strbuf_addch(sb, '0' + (c - code_characters));
                        if (ret)
                                break;
                } else {
                        ret = strbuf_addch(sb, *x);
                        if (ret)
                                break;
                }
        }
        return ret;
}

static int decode_metric_id(struct strbuf *sb, const char *x)
{
        const char *orig = x;
        size_t i;
        char c;
        int ret;

        for (; *x; x++) {
                c = *x;
                if (*x == '!') {
                        x++;
                        i = *x - '0';
                        if (i > strlen(code_characters)) {
                                pr_err("Bad metric-id encoding in: '%s'", orig);
                                return -1;
                        }
                        c = code_characters[i];
                }
                ret = strbuf_addch(sb, c);
                if (ret)
                        return ret;
        }
        return 0;
}

static int decode_all_metric_ids(struct evlist *perf_evlist, const char *modifier)
{
        struct evsel *ev;
        struct strbuf sb = STRBUF_INIT;
        char *cur;
        int ret = 0;

        evlist__for_each_entry(perf_evlist, ev) {
                if (!ev->metric_id)
                        continue;

                ret = strbuf_setlen(&sb, 0);
                if (ret)
                        break;

                ret = decode_metric_id(&sb, ev->metric_id);
                if (ret)
                        break;

                free((char *)ev->metric_id);
                ev->metric_id = strdup(sb.buf);
                if (!ev->metric_id) {
                        ret = -ENOMEM;
                        break;
                }
                /*
                 * If the name is just the parsed event, use the metric-id to
                 * give a more friendly display version.
                 */
                if (strstr(ev->name, "metric-id=")) {
                        bool has_slash = false;

                        zfree(&ev->name);
                        for (cur = strchr(sb.buf, '@') ; cur; cur = strchr(++cur, '@')) {
                                *cur = '/';
                                has_slash = true;
                        }

                        if (modifier) {
                                if (!has_slash && !strchr(sb.buf, ':')) {
                                        ret = strbuf_addch(&sb, ':');
                                        if (ret)
                                                break;
                                }
                                ret = strbuf_addstr(&sb, modifier);
                                if (ret)
                                        break;
                        }
                        ev->name = strdup(sb.buf);
                        if (!ev->name) {
                                ret = -ENOMEM;
                                break;
                        }
                }
        }
        strbuf_release(&sb);
        return ret;
}

static int metricgroup__build_event_string(struct strbuf *events,
                                           const struct expr_parse_ctx *ctx,
                                           const char *modifier,
                                           bool group_events)
{
        struct hashmap_entry *cur;
        size_t bkt;
        bool no_group = true, has_tool_events = false;
        bool tool_events[TOOL_PMU__EVENT_MAX] = {false};
        int ret = 0;

#define RETURN_IF_NON_ZERO(x) do { if (x) return x; } while (0)

        hashmap__for_each_entry(ctx->ids, cur, bkt) {
                const char *sep, *rsep, *id = cur->pkey;
                enum tool_pmu_event ev;

                pr_debug("found event %s\n", id);

                /* Always move tool events outside of the group. */
                ev = tool_pmu__str_to_event(id);
                if (ev != TOOL_PMU__EVENT_NONE) {
                        has_tool_events = true;
                        tool_events[ev] = true;
                        continue;
                }
                /* Separate events with commas and open the group if necessary. */
                if (no_group) {
                        if (group_events) {
                                ret = strbuf_addch(events, '{');
                                RETURN_IF_NON_ZERO(ret);
                        }

                        no_group = false;
                } else {
                        ret = strbuf_addch(events, ',');
                        RETURN_IF_NON_ZERO(ret);
                }
                /*
                 * Encode the ID as an event string. Add a qualifier for
                 * metric_id that is the original name except with characters
                 * that parse-events can't parse replaced. For example,
                 * 'msr@tsc@' gets added as msr/tsc,metric-id=msr!3tsc!3/
                 */
                sep = strchr(id, '@');
                if (sep != NULL) {
                        ret = strbuf_add(events, id, sep - id);
                        RETURN_IF_NON_ZERO(ret);
                        ret = strbuf_addch(events, '/');
                        RETURN_IF_NON_ZERO(ret);
                        rsep = strrchr(sep, '@');
                        ret = strbuf_add(events, sep + 1, rsep - sep - 1);
                        RETURN_IF_NON_ZERO(ret);
                        ret = strbuf_addstr(events, ",metric-id=");
                        RETURN_IF_NON_ZERO(ret);
                        sep = rsep;
                } else {
                        sep = strchr(id, ':');
                        if (sep != NULL) {
                                ret = strbuf_add(events, id, sep - id);
                                RETURN_IF_NON_ZERO(ret);
                        } else {
                                ret = strbuf_addstr(events, id);
                                RETURN_IF_NON_ZERO(ret);
                        }
                        ret = strbuf_addstr(events, "/metric-id=");
                        RETURN_IF_NON_ZERO(ret);
                }
                ret = encode_metric_id(events, id);
                RETURN_IF_NON_ZERO(ret);
                ret = strbuf_addstr(events, "/");
                RETURN_IF_NON_ZERO(ret);

                if (sep != NULL) {
                        ret = strbuf_addstr(events, sep + 1);
                        RETURN_IF_NON_ZERO(ret);
                }
                if (modifier) {
                        ret = strbuf_addstr(events, modifier);
                        RETURN_IF_NON_ZERO(ret);
                }
        }
        if (!no_group && group_events) {
                ret = strbuf_addf(events, "}:W");
                RETURN_IF_NON_ZERO(ret);
        }
        if (has_tool_events) {
                int i;

                tool_pmu__for_each_event(i) {
                        if (tool_events[i]) {
                                if (!no_group) {
                                        ret = strbuf_addch(events, ',');
                                        RETURN_IF_NON_ZERO(ret);
                                }
                                no_group = false;
                                ret = strbuf_addstr(events, tool_pmu__event_to_str(i));
                                RETURN_IF_NON_ZERO(ret);
                        }
                }
        }

        return ret;
#undef RETURN_IF_NON_ZERO
}

int __weak arch_get_runtimeparam(const struct pmu_metric *pm __maybe_unused)
{
        return 1;
}

/*
 * A singly linked list on the stack of the names of metrics being
 * processed. Used to identify recursion.
 */
struct visited_metric {
        const char *name;
        const struct visited_metric *parent;
};

struct metricgroup_add_iter_data {
        struct list_head *metric_list;
        const char *pmu;
        const char *metric_name;
        const char *modifier;
        int *ret;
        bool *has_match;
        bool metric_no_group;
        bool metric_no_threshold;
        const char *user_requested_cpu_list;
        bool system_wide;
        struct metric *root_metric;
        const struct visited_metric *visited;
        const struct pmu_metrics_table *table;
};

static int add_metric(struct list_head *metric_list,
                      const struct pmu_metric *pm,
                      const char *modifier,
                      bool metric_no_group,
                      bool metric_no_threshold,
                      const char *user_requested_cpu_list,
                      bool system_wide,
                      struct metric *root_metric,
                      const struct visited_metric *visited,
                      const struct pmu_metrics_table *table);

static int metricgroup__find_metric_callback(const struct pmu_metric *pm,
                                             const struct pmu_metrics_table *table  __maybe_unused,
                                             void *vdata)
{
        struct pmu_metric *copied_pm = vdata;

        memcpy(copied_pm, pm, sizeof(*pm));
        return 0;
}

/**
 * resolve_metric - Locate metrics within the root metric and recursively add
 *                    references to them.
 * @metric_list: The list the metric is added to.
 * @pmu: The PMU name to resolve metrics on, or "all" for all PMUs.
 * @modifier: if non-null event modifiers like "u".
 * @metric_no_group: Should events written to events be grouped "{}" or
 *                   global. Grouping is the default but due to multiplexing the
 *                   user may override.
 * @user_requested_cpu_list: Command line specified CPUs to record on.
 * @system_wide: Are events for all processes recorded.
 * @root_metric: Metrics may reference other metrics to form a tree. In this
 *               case the root_metric holds all the IDs and a list of referenced
 *               metrics. When adding a root this argument is NULL.
 * @visited: A singly linked list of metric names being added that is used to
 *           detect recursion.
 * @table: The table that is searched for metrics, most commonly the table for the
 *       architecture perf is running upon.
 */
static int resolve_metric(struct list_head *metric_list,
                          struct perf_pmu *pmu,
                          const char *modifier,
                          bool metric_no_group,
                          bool metric_no_threshold,
                          const char *user_requested_cpu_list,
                          bool system_wide,
                          struct metric *root_metric,
                          const struct visited_metric *visited,
                          const struct pmu_metrics_table *table)
{
        struct hashmap_entry *cur;
        size_t bkt;
        struct to_resolve {
                /* The metric to resolve. */
                struct pmu_metric pm;
                /*
                 * The key in the IDs map, this may differ from in case,
                 * etc. from pm->metric_name.
                 */
                const char *key;
        } *pending = NULL;
        int i, ret = 0, pending_cnt = 0;

        /*
         * Iterate all the parsed IDs and if there's a matching metric and it to
         * the pending array.
         */
        hashmap__for_each_entry(root_metric->pctx->ids, cur, bkt) {
                struct pmu_metric pm;

                if (pmu_metrics_table__find_metric(table, pmu, cur->pkey,
                                                   metricgroup__find_metric_callback,
                                                   &pm) != PMU_METRICS__NOT_FOUND) {
                        pending = realloc(pending,
                                        (pending_cnt + 1) * sizeof(struct to_resolve));
                        if (!pending)
                                return -ENOMEM;

                        memcpy(&pending[pending_cnt].pm, &pm, sizeof(pm));
                        pending[pending_cnt].key = cur->pkey;
                        pending_cnt++;
                }
        }

        /* Remove the metric IDs from the context. */
        for (i = 0; i < pending_cnt; i++)
                expr__del_id(root_metric->pctx, pending[i].key);

        /*
         * Recursively add all the metrics, IDs are added to the root metric's
         * context.
         */
        for (i = 0; i < pending_cnt; i++) {
                ret = add_metric(metric_list, &pending[i].pm, modifier, metric_no_group,
                                 metric_no_threshold, user_requested_cpu_list, system_wide,
                                 root_metric, visited, table);
                if (ret)
                        break;
        }

        free(pending);
        return ret;
}

/**
 * __add_metric - Add a metric to metric_list.
 * @metric_list: The list the metric is added to.
 * @pm: The pmu_metric containing the metric to be added.
 * @modifier: if non-null event modifiers like "u".
 * @metric_no_group: Should events written to events be grouped "{}" or
 *                   global. Grouping is the default but due to multiplexing the
 *                   user may override.
 * @metric_no_threshold: Should threshold expressions be ignored?
 * @runtime: A special argument for the parser only known at runtime.
 * @user_requested_cpu_list: Command line specified CPUs to record on.
 * @system_wide: Are events for all processes recorded.
 * @root_metric: Metrics may reference other metrics to form a tree. In this
 *               case the root_metric holds all the IDs and a list of referenced
 *               metrics. When adding a root this argument is NULL.
 * @visited: A singly linked list of metric names being added that is used to
 *           detect recursion.
 * @table: The table that is searched for metrics, most commonly the table for the
 *       architecture perf is running upon.
 */
static int __add_metric(struct list_head *metric_list,
                        const struct pmu_metric *pm,
                        const char *modifier,
                        bool metric_no_group,
                        bool metric_no_threshold,
                        int runtime,
                        const char *user_requested_cpu_list,
                        bool system_wide,
                        struct metric *root_metric,
                        const struct visited_metric *visited,
                        const struct pmu_metrics_table *table)
{
        const struct visited_metric *vm;
        int ret;
        bool is_root = !root_metric;
        const char *expr;
        struct visited_metric visited_node = {
                .name = pm->metric_name,
                .parent = visited,
        };

        for (vm = visited; vm; vm = vm->parent) {
                if (!strcmp(pm->metric_name, vm->name)) {
                        pr_err("failed: recursion detected for %s\n", pm->metric_name);
                        return -1;
                }
        }

        if (is_root) {
                /*
                 * This metric is the root of a tree and may reference other
                 * metrics that are added recursively.
                 */
                root_metric = metric__new(pm, modifier, metric_no_group, metric_no_threshold,
                                          runtime, user_requested_cpu_list, system_wide);
                if (!root_metric)
                        return -ENOMEM;

        } else {
                int cnt = 0;

                /*
                 * This metric was referenced in a metric higher in the
                 * tree. Check if the same metric is already resolved in the
                 * metric_refs list.
                 */
                if (root_metric->metric_refs) {
                        for (; root_metric->metric_refs[cnt].metric_name; cnt++) {
                                if (!strcmp(pm->metric_name,
                                            root_metric->metric_refs[cnt].metric_name))
                                        return 0;
                        }
                }

                /* Create reference. Need space for the entry and the terminator. */
                root_metric->metric_refs = realloc(root_metric->metric_refs,
                                                (cnt + 2) * sizeof(struct metric_ref));
                if (!root_metric->metric_refs)
                        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.
                 */
                root_metric->metric_refs[cnt].metric_name = pm->metric_name;
                root_metric->metric_refs[cnt].metric_expr = pm->metric_expr;

                /* Null terminate array. */
                root_metric->metric_refs[cnt+1].metric_name = NULL;
                root_metric->metric_refs[cnt+1].metric_expr = NULL;
        }

        /*
         * For both the parent and referenced metrics, we parse
         * all the metric's IDs and add it to the root context.
         */
        ret = 0;
        expr = pm->metric_expr;
        if (is_root && pm->metric_threshold) {
                /*
                 * Threshold expressions are built off the actual metric. Switch
                 * to use that in case of additional necessary events. Change
                 * the visited node name to avoid this being flagged as
                 * recursion. If the threshold events are disabled, just use the
                 * metric's name as a reference. This allows metric threshold
                 * computation if there are sufficient events.
                 */
                assert(strstr(pm->metric_threshold, pm->metric_name));
                expr = metric_no_threshold ? pm->metric_name : pm->metric_threshold;
                visited_node.name = "__threshold__";
        }
        if (expr__find_ids(expr, NULL, root_metric->pctx) < 0) {
                /* Broken metric. */
                ret = -EINVAL;
        }
        if (!ret) {
                /* Resolve referenced metrics. */
                struct perf_pmu *pmu;

                if (pm->pmu && pm->pmu[0] != '\0')
                        pmu = perf_pmus__find(pm->pmu);
                else
                        pmu = perf_pmus__scan_core(/*pmu=*/ NULL);

                ret = resolve_metric(metric_list, pmu, modifier, metric_no_group,
                                     metric_no_threshold, user_requested_cpu_list,
                                     system_wide, root_metric, &visited_node,
                                     table);
        }
        if (ret) {
                if (is_root)
                        metric__free(root_metric);

        } else if (is_root)
                list_add(&root_metric->nd, metric_list);

        return ret;
}

static int add_metric(struct list_head *metric_list,
                      const struct pmu_metric *pm,
                      const char *modifier,
                      bool metric_no_group,
                      bool metric_no_threshold,
                      const char *user_requested_cpu_list,
                      bool system_wide,
                      struct metric *root_metric,
                      const struct visited_metric *visited,
                      const struct pmu_metrics_table *table)
{
        int ret = 0;

        pr_debug("metric expr %s for %s\n", pm->metric_expr, pm->metric_name);

        if (!strstr(pm->metric_expr, "?")) {
                ret = __add_metric(metric_list, pm, modifier, metric_no_group,
                                   metric_no_threshold, 0, user_requested_cpu_list,
                                   system_wide, root_metric, visited, table);
        } else {
                int j, count;

                count = arch_get_runtimeparam(pm);

                /* 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++)
                        ret = __add_metric(metric_list, pm, modifier, metric_no_group,
                                           metric_no_threshold, j, user_requested_cpu_list,
                                           system_wide, root_metric, visited, table);
        }

        return ret;
}

/**
 * metric_list_cmp - list_sort comparator that sorts metrics with more events to
 *                   the front. tool events are excluded from the count.
 */
static int metric_list_cmp(void *priv __maybe_unused, const struct list_head *l,
                           const struct list_head *r)
{
        const struct metric *left = container_of(l, struct metric, nd);
        const struct metric *right = container_of(r, struct metric, nd);
        struct expr_id_data *data;
        int i, left_count, right_count;

        left_count = hashmap__size(left->pctx->ids);
        tool_pmu__for_each_event(i) {
                if (!expr__get_id(left->pctx, tool_pmu__event_to_str(i), &data))
                        left_count--;
        }

        right_count = hashmap__size(right->pctx->ids);
        tool_pmu__for_each_event(i) {
                if (!expr__get_id(right->pctx, tool_pmu__event_to_str(i), &data))
                        right_count--;
        }

        return right_count - left_count;
}

/**
 * default_metricgroup_cmp - Implements complex key for the Default metricgroup
 *                           that first sorts by default_metricgroup_name, then
 *                           metric_name.
 */
static int default_metricgroup_cmp(void *priv __maybe_unused,
                                   const struct list_head *l,
                                   const struct list_head *r)
{
        const struct metric *left = container_of(l, struct metric, nd);
        const struct metric *right = container_of(r, struct metric, nd);
        int diff = strcmp(right->default_metricgroup_name, left->default_metricgroup_name);

        if (diff)
                return diff;

        return strcmp(right->metric_name, left->metric_name);
}

struct metricgroup__add_metric_data {
        struct list_head *list;
        const char *pmu;
        const char *metric_name;
        const char *modifier;
        const char *user_requested_cpu_list;
        bool metric_no_group;
        bool metric_no_threshold;
        bool system_wide;
        bool has_match;
};

static int metricgroup__add_metric_callback(const struct pmu_metric *pm,
                                            const struct pmu_metrics_table *table,
                                            void *vdata)
{
        struct metricgroup__add_metric_data *data = vdata;
        int ret = 0;

        if (pm->metric_expr && match_pm_metric_or_groups(pm, data->pmu, data->metric_name)) {
                bool metric_no_group = data->metric_no_group ||
                        match_metric_or_groups(pm->metricgroup_no_group, data->metric_name);

                data->has_match = true;
                ret = add_metric(data->list, pm, data->modifier, metric_no_group,
                                 data->metric_no_threshold, data->user_requested_cpu_list,
                                 data->system_wide, /*root_metric=*/NULL,
                                 /*visited_metrics=*/NULL, table);
        }
        return ret;
}

/**
 * metricgroup__add_metric - Find and add a metric, or a metric group.
 * @pmu: The PMU name to search for metrics on, or "all" for all PMUs.
 * @metric_name: The name of the metric or metric group. For example, "IPC"
 *               could be the name of a metric and "TopDownL1" the name of a
 *               metric group.
 * @modifier: if non-null event modifiers like "u".
 * @metric_no_group: Should events written to events be grouped "{}" or
 *                   global. Grouping is the default but due to multiplexing the
 *                   user may override.
 * @user_requested_cpu_list: Command line specified CPUs to record on.
 * @system_wide: Are events for all processes recorded.
 * @metric_list: The list that the metric or metric group are added to.
 * @table: The table that is searched for metrics, most commonly the table for the
 *       architecture perf is running upon.
 */
static int metricgroup__add_metric(const char *pmu, const char *metric_name, const char *modifier,
                                   bool metric_no_group, bool metric_no_threshold,
                                   const char *user_requested_cpu_list,
                                   bool system_wide,
                                   struct list_head *metric_list,
                                   const struct pmu_metrics_table *table)
{
        LIST_HEAD(list);
        int ret;
        struct metricgroup__add_metric_data data = {
                .list = &list,
                .pmu = pmu,
                .metric_name = metric_name,
                .modifier = modifier,
                .metric_no_group = metric_no_group,
                .metric_no_threshold = metric_no_threshold,
                .user_requested_cpu_list = user_requested_cpu_list,
                .system_wide = system_wide,
                .has_match = false,
        };

        /*
         * Iterate over all metrics seeing if metric matches either the
         * name or group. When it does add the metric to the list.
         */
        ret = metricgroup__for_each_metric(table, metricgroup__add_metric_callback, &data);
        if (!ret && !data.has_match)
                ret = -EINVAL;

        /*
         * add to metric_list so that they can be released
         * even if it's failed
         */
        list_splice(&list, metric_list);
        return ret;
}

/**
 * metricgroup__add_metric_list - Find and add metrics, or metric groups,
 *                                specified in a list.
 * @pmu: A pmu to restrict the metrics to, or "all" for all PMUS.
 * @list: the list of metrics or metric groups. For example, "IPC,CPI,TopDownL1"
 *        would match the IPC and CPI metrics, and TopDownL1 would match all
 *        the metrics in the TopDownL1 group.
 * @metric_no_group: Should events written to events be grouped "{}" or
 *                   global. Grouping is the default but due to multiplexing the
 *                   user may override.
 * @user_requested_cpu_list: Command line specified CPUs to record on.
 * @system_wide: Are events for all processes recorded.
 * @metric_list: The list that metrics are added to.
 * @table: The table that is searched for metrics, most commonly the table for the
 *       architecture perf is running upon.
 */
static int metricgroup__add_metric_list(const char *pmu, const char *list,
                                        bool metric_no_group,
                                        bool metric_no_threshold,
                                        const char *user_requested_cpu_list,
                                        bool system_wide, struct list_head *metric_list,
                                        const struct pmu_metrics_table *table)
{
        char *list_itr, *list_copy, *metric_name, *modifier;
        int ret, count = 0;

        list_copy = strdup(list);
        if (!list_copy)
                return -ENOMEM;
        list_itr = list_copy;

        while ((metric_name = strsep(&list_itr, ",")) != NULL) {
                modifier = strchr(metric_name, ':');
                if (modifier)
                        *modifier++ = '\0';

                ret = metricgroup__add_metric(pmu, metric_name, modifier,
                                              metric_no_group, metric_no_threshold,
                                              user_requested_cpu_list,
                                              system_wide, metric_list, table);
                if (ret == -EINVAL)
                        pr_err("Cannot find metric or group `%s'\n", metric_name);

                if (ret)
                        break;

                count++;
        }
        free(list_copy);

        if (!ret) {
                /*
                 * Warn about nmi_watchdog if any parsed metrics had the
                 * NO_NMI_WATCHDOG constraint.
                 */
                metric__watchdog_constraint_hint(NULL, /*foot=*/true);
                /* No metrics. */
                if (count == 0)
                        return -EINVAL;
        }
        return ret;
}

static void metricgroup__free_metrics(struct list_head *metric_list)
{
        struct metric *m, *tmp;

        list_for_each_entry_safe (m, tmp, metric_list, nd) {
                list_del_init(&m->nd);
                metric__free(m);
        }
}

/**
 * find_tool_events - Search for the pressence of tool events in metric_list.
 * @metric_list: List to take metrics from.
 * @tool_events: Array of false values, indices corresponding to tool events set
 *               to true if tool event is found.
 */
static void find_tool_events(const struct list_head *metric_list,
                             bool tool_events[TOOL_PMU__EVENT_MAX])
{
        struct metric *m;

        list_for_each_entry(m, metric_list, nd) {
                int i;

                tool_pmu__for_each_event(i) {
                        struct expr_id_data *data;

                        if (!tool_events[i] &&
                            !expr__get_id(m->pctx, tool_pmu__event_to_str(i), &data))
                                tool_events[i] = true;
                }
        }
}

/**
 * build_combined_expr_ctx - Make an expr_parse_ctx with all !group_events
 *                           metric IDs, as the IDs are held in a set,
 *                           duplicates will be removed.
 * @metric_list: List to take metrics from.
 * @combined: Out argument for result.
 */
static int build_combined_expr_ctx(const struct list_head *metric_list,
                                   struct expr_parse_ctx **combined)
{
        struct hashmap_entry *cur;
        size_t bkt;
        struct metric *m;
        char *dup;
        int ret;

        *combined = expr__ctx_new();
        if (!*combined)
                return -ENOMEM;

        list_for_each_entry(m, metric_list, nd) {
                if (!m->group_events && !m->modifier) {
                        hashmap__for_each_entry(m->pctx->ids, cur, bkt) {
                                dup = strdup(cur->pkey);
                                if (!dup) {
                                        ret = -ENOMEM;
                                        goto err_out;
                                }
                                ret = expr__add_id(*combined, dup);
                                if (ret)
                                        goto err_out;
                        }
                }
        }
        return 0;
err_out:
        expr__ctx_free(*combined);
        *combined = NULL;
        return ret;
}

/**
 * parse_ids - Build the event string for the ids and parse them creating an
 *             evlist. The encoded metric_ids are decoded.
 * @metric_no_merge: is metric sharing explicitly disabled.
 * @fake_pmu: use a fake PMU when testing metrics not supported by the current CPU.
 * @ids: the event identifiers parsed from a metric.
 * @modifier: any modifiers added to the events.
 * @group_events: should events be placed in a weak group.
 * @tool_events: entries set true if the tool event of index could be present in
 *               the overall list of metrics.
 * @out_evlist: the created list of events.
 */
static int parse_ids(bool metric_no_merge, bool fake_pmu,
                     struct expr_parse_ctx *ids, const char *modifier,
                     bool group_events, const bool tool_events[TOOL_PMU__EVENT_MAX],
                     struct evlist **out_evlist)
{
        struct parse_events_error parse_error;
        struct evlist *parsed_evlist;
        struct strbuf events = STRBUF_INIT;
        int ret;

        *out_evlist = NULL;
        if (!metric_no_merge || hashmap__size(ids->ids) == 0) {
                bool added_event = false;
                int i;
                /*
                 * We may fail to share events between metrics because a tool
                 * event isn't present in one metric. For example, a ratio of
                 * cache misses doesn't need duration_time but the same events
                 * may be used for a misses per second. Events without sharing
                 * implies multiplexing, that is best avoided, so place
                 * all tool events in every group.
                 *
                 * Also, there may be no ids/events in the expression parsing
                 * context because of constant evaluation, e.g.:
                 *    event1 if #smt_on else 0
                 * Add a tool event to avoid a parse error on an empty string.
                 */
                tool_pmu__for_each_event(i) {
                        if (tool_events[i]) {
                                char *tmp = strdup(tool_pmu__event_to_str(i));

                                if (!tmp)
                                        return -ENOMEM;
                                ids__insert(ids->ids, tmp);
                                added_event = true;
                        }
                }
                if (!added_event && hashmap__size(ids->ids) == 0) {
                        char *tmp = strdup("duration_time");

                        if (!tmp)
                                return -ENOMEM;
                        ids__insert(ids->ids, tmp);
                }
        }
        ret = metricgroup__build_event_string(&events, ids, modifier,
                                              group_events);
        if (ret)
                return ret;

        parsed_evlist = evlist__new();
        if (!parsed_evlist) {
                ret = -ENOMEM;
                goto err_out;
        }
        pr_debug("Parsing metric events '%s'\n", events.buf);
        parse_events_error__init(&parse_error);
        ret = __parse_events(parsed_evlist, events.buf, /*pmu_filter=*/NULL,
                             &parse_error, fake_pmu, /*warn_if_reordered=*/false,
                             /*fake_tp=*/false);
        if (ret) {
                parse_events_error__print(&parse_error, events.buf);
                goto err_out;
        }
        ret = decode_all_metric_ids(parsed_evlist, modifier);
        if (ret)
                goto err_out;

        *out_evlist = parsed_evlist;
        parsed_evlist = NULL;
err_out:
        parse_events_error__exit(&parse_error);
        evlist__delete(parsed_evlist);
        strbuf_release(&events);
        return ret;
}

/* How many times will a given evsel be used in a set of metrics? */
static int count_uses(struct list_head *metric_list, struct evsel *evsel)
{
        const char *metric_id = evsel__metric_id(evsel);
        struct metric *m;
        int uses = 0;

        list_for_each_entry(m, metric_list, nd) {
                if (hashmap__find(m->pctx->ids, metric_id, NULL))
                        uses++;
        }
        return uses;
}

/*
 * Select the evsel that stat-display will use to trigger shadow/metric
 * printing. Pick the least shared non-tool evsel, encouraging metrics to be
 * with a hardware counter that is specific to them.
 */
static struct evsel *pick_display_evsel(struct list_head *metric_list,
                                        struct evsel **metric_events)
{
        struct evsel *selected = metric_events[0];
        size_t selected_uses;
        bool selected_is_tool;

        if (!selected)
                return NULL;

        selected_uses = count_uses(metric_list, selected);
        selected_is_tool = evsel__is_tool(selected);
        for (int i = 1; metric_events[i]; i++) {
                struct evsel *candidate = metric_events[i];
                size_t candidate_uses = count_uses(metric_list, candidate);

                if ((selected_is_tool && !evsel__is_tool(candidate)) ||
                    (candidate_uses < selected_uses)) {
                        selected = candidate;
                        selected_uses = candidate_uses;
                        selected_is_tool = evsel__is_tool(selected);
                }
        }
        return selected;
}

static int parse_groups(struct evlist *perf_evlist,
                        const char *pmu, const char *str,
                        bool metric_no_group,
                        bool metric_no_merge,
                        bool metric_no_threshold,
                        const char *user_requested_cpu_list,
                        bool system_wide,
                        bool fake_pmu,
                        const struct pmu_metrics_table *table)
{
        struct evlist *combined_evlist = NULL;
        LIST_HEAD(metric_list);
        struct metric *m;
        bool tool_events[TOOL_PMU__EVENT_MAX] = {false};
        bool is_default = !strcmp(str, "Default");
        int ret;

        ret = metricgroup__add_metric_list(pmu, str, metric_no_group, metric_no_threshold,
                                           user_requested_cpu_list,
                                           system_wide, &metric_list, table);
        if (ret)
                goto out;

        /* Sort metrics from largest to smallest. */
        list_sort(NULL, &metric_list, metric_list_cmp);

        if (!metric_no_merge) {
                struct expr_parse_ctx *combined = NULL;

                find_tool_events(&metric_list, tool_events);

                ret = build_combined_expr_ctx(&metric_list, &combined);

                if (!ret && combined && hashmap__size(combined->ids)) {
                        ret = parse_ids(metric_no_merge, fake_pmu, combined,
                                        /*modifier=*/NULL,
                                        /*group_events=*/false,
                                        tool_events,
                                        &combined_evlist);
                }
                if (combined)
                        expr__ctx_free(combined);

                if (ret)
                        goto out;
        }

        if (is_default)
                list_sort(NULL, &metric_list, default_metricgroup_cmp);

        list_for_each_entry(m, &metric_list, nd) {
                struct metric_event *me;
                struct evsel **metric_events;
                struct evlist *metric_evlist = NULL;
                struct metric *n;
                struct metric_expr *expr;

                if (combined_evlist && !m->group_events) {
                        metric_evlist = combined_evlist;
                } else if (!metric_no_merge) {
                        /*
                         * See if the IDs for this metric are a subset of an
                         * earlier metric.
                         */
                        list_for_each_entry(n, &metric_list, nd) {
                                if (m == n)
                                        break;

                                if (n->evlist == NULL)
                                        continue;

                                if ((!m->modifier && n->modifier) ||
                                    (m->modifier && !n->modifier) ||
                                    (m->modifier && n->modifier &&
                                            strcmp(m->modifier, n->modifier)))
                                        continue;

                                if ((!m->pmu && n->pmu) ||
                                    (m->pmu && !n->pmu) ||
                                    (m->pmu && n->pmu && strcmp(m->pmu, n->pmu)))
                                        continue;

                                if (expr__subset_of_ids(n->pctx, m->pctx)) {
                                        pr_debug("Events in '%s' fully contained within '%s'\n",
                                                 m->metric_name, n->metric_name);
                                        metric_evlist = n->evlist;
                                        break;
                                }

                        }
                }
                if (!metric_evlist) {
                        ret = parse_ids(metric_no_merge, fake_pmu, m->pctx, m->modifier,
                                        m->group_events, tool_events, &m->evlist);
                        if (ret)
                                goto out;

                        metric_evlist = m->evlist;
                }
                ret = setup_metric_events(fake_pmu ? "all" : m->pmu, m->pctx->ids,
                                          metric_evlist, &metric_events);
                if (ret) {
                        pr_err("Cannot resolve IDs for %s: %s\n",
                                m->metric_name, m->metric_expr);
                        goto out;
                }

                me = metricgroup__lookup(&perf_evlist->metric_events,
                                         pick_display_evsel(&metric_list, metric_events),
                                         /*create=*/true);

                expr = malloc(sizeof(struct metric_expr));
                if (!expr) {
                        ret = -ENOMEM;
                        free(metric_events);
                        goto out;
                }

                expr->metric_refs = m->metric_refs;
                m->metric_refs = NULL;
                expr->metric_expr = m->metric_expr;
                if (m->modifier) {
                        char *tmp;

                        if (asprintf(&tmp, "%s:%s", m->metric_name, m->modifier) < 0)
                                expr->metric_name = NULL;
                        else
                                expr->metric_name = tmp;
                } else
                        expr->metric_name = strdup(m->metric_name);

                if (!expr->metric_name) {
                        ret = -ENOMEM;
                        free(expr);
                        free(metric_events);
                        goto out;
                }
                if (m->default_show_events) {
                        struct evsel *pos;

                        for (int i = 0; metric_events[i]; i++)
                                metric_events[i]->default_show_events = true;
                        evlist__for_each_entry(metric_evlist, pos) {
                                if (pos->metric_leader && pos->metric_leader->default_show_events)
                                        pos->default_show_events = true;
                        }
                }
                expr->metric_threshold = m->metric_threshold;
                expr->metric_unit = m->metric_unit;
                expr->metric_events = metric_events;
                expr->runtime = m->pctx->sctx.runtime;
                expr->default_metricgroup_name = m->default_metricgroup_name;
                me->is_default = is_default;
                list_add(&expr->nd, &me->head);
        }


        if (combined_evlist) {
                evlist__splice_list_tail(perf_evlist, &combined_evlist->core.entries);
                evlist__delete(combined_evlist);
        }

        list_for_each_entry(m, &metric_list, nd) {
                if (m->evlist)
                        evlist__splice_list_tail(perf_evlist, &m->evlist->core.entries);
        }

out:
        metricgroup__free_metrics(&metric_list);
        return ret;
}

int metricgroup__parse_groups(struct evlist *perf_evlist,
                              const char *pmu,
                              const char *str,
                              bool metric_no_group,
                              bool metric_no_merge,
                              bool metric_no_threshold,
                              const char *user_requested_cpu_list,
                              bool system_wide,
                              bool hardware_aware_grouping)
{
        const struct pmu_metrics_table *table = pmu_metrics_table__find();

        if (hardware_aware_grouping)
                pr_debug("Use hardware aware grouping instead of traditional metric grouping method\n");

        return parse_groups(perf_evlist, pmu, str, metric_no_group, metric_no_merge,
                            metric_no_threshold, user_requested_cpu_list, system_wide,
                            /*fake_pmu=*/false, table);
}

int metricgroup__parse_groups_test(struct evlist *evlist,
                                   const struct pmu_metrics_table *table,
                                   const char *str)
{
        return parse_groups(evlist, "all", str,
                            /*metric_no_group=*/false,
                            /*metric_no_merge=*/false,
                            /*metric_no_threshold=*/false,
                            /*user_requested_cpu_list=*/NULL,
                            /*system_wide=*/false,
                            /*fake_pmu=*/true, table);
}

struct metricgroup__has_metric_data {
        const char *pmu;
        const char *metric_or_groups;
};
static int metricgroup__has_metric_or_groups_callback(const struct pmu_metric *pm,
                                                      const struct pmu_metrics_table *table
                                                        __maybe_unused,
                                                      void *vdata)
{
        struct metricgroup__has_metric_data *data = vdata;

        return match_pm_metric_or_groups(pm, data->pmu, data->metric_or_groups) ? 1 : 0;
}

bool metricgroup__has_metric_or_groups(const char *pmu, const char *metric_or_groups)
{
        const struct pmu_metrics_table *table = pmu_metrics_table__find();
        struct metricgroup__has_metric_data data = {
                .pmu = pmu,
                .metric_or_groups = metric_or_groups,
        };

        return metricgroup__for_each_metric(table,
                                            metricgroup__has_metric_or_groups_callback,
                                            &data)
                ? true : false;
}

static int metricgroup__topdown_max_level_callback(const struct pmu_metric *pm,
                                            const struct pmu_metrics_table *table __maybe_unused,
                                            void *data)
{
        unsigned int *max_level = data;
        unsigned int level;
        const char *p = strstr(pm->metric_group ?: "", "TopdownL");

        if (!p || p[8] == '\0')
                return 0;

        level = p[8] - '0';
        if (level > *max_level)
                *max_level = level;

        return 0;
}

unsigned int metricgroups__topdown_max_level(void)
{
        unsigned int max_level = 0;
        const struct pmu_metrics_table *table = pmu_metrics_table__find();

        if (!table)
                return false;

        pmu_metrics_table__for_each_metric(table, metricgroup__topdown_max_level_callback,
                                          &max_level);
        return max_level;
}

int metricgroup__copy_metric_events(struct evlist *evlist, struct cgroup *cgrp,
                                    struct rblist *new_metric_events,
                                    struct rblist *old_metric_events)
{
        unsigned int 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, /*create=*/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);

                new_me->is_default = old_me->is_default;
                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_threshold = old_expr->metric_threshold;
                        new_expr->metric_name = strdup(old_expr->metric_name);
                        if (!new_expr->metric_name)
                                return -ENOMEM;

                        new_expr->metric_unit = old_expr->metric_unit;
                        new_expr->runtime = old_expr->runtime;
                        new_expr->default_metricgroup_name = old_expr->default_metricgroup_name;

                        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) {
                                zfree(&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) {
                                        zfree(&new_expr->metric_events);
                                        zfree(&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;
}