// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
 *
 * Parts came from builtin-{top,stat,record}.c, see those files for further
 * copyright notes.
 */
#include <api/fs/fs.h>
#include <errno.h>
#include <inttypes.h>
#include <poll.h>
#include "cpumap.h"
#include "util/mmap.h"
#include "thread_map.h"
#include "target.h"
#include "evlist.h"
#include "evsel.h"
#include "record.h"
#include "debug.h"
#include "units.h"
#include "bpf_counter.h"
#include <internal/lib.h> // page_size
#include "affinity.h"
#include "../perf.h"
#include "asm/bug.h"
#include "bpf-event.h"
#include "util/event.h"
#include "util/string2.h"
#include "util/perf_api_probe.h"
#include "util/evsel_fprintf.h"
#include "util/pmu.h"
#include "util/sample.h"
#include "util/bpf-filter.h"
#include "util/stat.h"
#include "util/util.h"
#include "util/env.h"
#include "util/intel-tpebs.h"
#include "util/metricgroup.h"
#include "util/strbuf.h"
#include <signal.h>
#include <unistd.h>
#include <sched.h>
#include <stdlib.h>

#include "parse-events.h"
#include <subcmd/parse-options.h>

#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/prctl.h>
#include <sys/timerfd.h>
#include <sys/wait.h>

#include <linux/bitops.h>
#include <linux/hash.h>
#include <linux/log2.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/time64.h>
#include <linux/zalloc.h>
#include <perf/evlist.h>
#include <perf/evsel.h>
#include <perf/cpumap.h>
#include <perf/mmap.h>

#include <internal/xyarray.h>

#ifdef LACKS_SIGQUEUE_PROTOTYPE
int sigqueue(pid_t pid, int sig, const union sigval value);
#endif

#define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
#define SID(e, x, y) xyarray__entry(e->core.sample_id, x, y)

void evlist__init(struct evlist *evlist, struct perf_cpu_map *cpus,
                  struct perf_thread_map *threads)
{
        perf_evlist__init(&evlist->core);
        perf_evlist__set_maps(&evlist->core, cpus, threads);
        evlist->workload.pid = -1;
        evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
        evlist->ctl_fd.fd = -1;
        evlist->ctl_fd.ack = -1;
        evlist->ctl_fd.pos = -1;
        evlist->nr_br_cntr = -1;
        metricgroup__rblist_init(&evlist->metric_events);
        INIT_LIST_HEAD(&evlist->deferred_samples);
}

struct evlist *evlist__new(void)
{
        struct evlist *evlist = zalloc(sizeof(*evlist));

        if (evlist != NULL)
                evlist__init(evlist, NULL, NULL);

        return evlist;
}

struct evlist *evlist__new_default(void)
{
        struct evlist *evlist = evlist__new();
        bool can_profile_kernel;
        struct perf_pmu *pmu = NULL;

        if (!evlist)
                return NULL;

        can_profile_kernel = perf_event_paranoid_check(1);

        while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
                char buf[256];
                int err;

                snprintf(buf, sizeof(buf), "%s/cycles/%s", pmu->name,
                         can_profile_kernel ? "P" : "Pu");
                err = parse_event(evlist, buf);
                if (err) {
                        evlist__delete(evlist);
                        return NULL;
                }
        }

        if (evlist->core.nr_entries > 1) {
                struct evsel *evsel;

                evlist__for_each_entry(evlist, evsel)
                        evsel__set_sample_id(evsel, /*can_sample_identifier=*/false);
        }

        return evlist;
}

struct evlist *evlist__new_dummy(void)
{
        struct evlist *evlist = evlist__new();

        if (evlist && evlist__add_dummy(evlist)) {
                evlist__delete(evlist);
                evlist = NULL;
        }

        return evlist;
}

/**
 * evlist__set_id_pos - set the positions of event ids.
 * @evlist: selected event list
 *
 * Events with compatible sample types all have the same id_pos
 * and is_pos.  For convenience, put a copy on evlist.
 */
void evlist__set_id_pos(struct evlist *evlist)
{
        struct evsel *first = evlist__first(evlist);

        evlist->id_pos = first->id_pos;
        evlist->is_pos = first->is_pos;
}

static void evlist__update_id_pos(struct evlist *evlist)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel)
                evsel__calc_id_pos(evsel);

        evlist__set_id_pos(evlist);
}

static void evlist__purge(struct evlist *evlist)
{
        struct evsel *pos, *n;

        evlist__for_each_entry_safe(evlist, n, pos) {
                list_del_init(&pos->core.node);
                pos->evlist = NULL;
                evsel__delete(pos);
        }

        evlist->core.nr_entries = 0;
}

void evlist__exit(struct evlist *evlist)
{
        metricgroup__rblist_exit(&evlist->metric_events);
        event_enable_timer__exit(&evlist->eet);
        zfree(&evlist->mmap);
        zfree(&evlist->overwrite_mmap);
        perf_evlist__exit(&evlist->core);
}

void evlist__delete(struct evlist *evlist)
{
        if (evlist == NULL)
                return;

        evlist__free_stats(evlist);
        evlist__munmap(evlist);
        evlist__close(evlist);
        evlist__purge(evlist);
        evlist__exit(evlist);
        free(evlist);
}

void evlist__add(struct evlist *evlist, struct evsel *entry)
{
        perf_evlist__add(&evlist->core, &entry->core);
        entry->evlist = evlist;
        entry->tracking = !entry->core.idx;

        if (evlist->core.nr_entries == 1)
                evlist__set_id_pos(evlist);
}

void evlist__remove(struct evlist *evlist, struct evsel *evsel)
{
        evsel->evlist = NULL;
        perf_evlist__remove(&evlist->core, &evsel->core);
}

void evlist__splice_list_tail(struct evlist *evlist, struct list_head *list)
{
        while (!list_empty(list)) {
                struct evsel *evsel, *temp, *leader = NULL;

                __evlist__for_each_entry_safe(list, temp, evsel) {
                        list_del_init(&evsel->core.node);
                        evlist__add(evlist, evsel);
                        leader = evsel;
                        break;
                }

                __evlist__for_each_entry_safe(list, temp, evsel) {
                        if (evsel__has_leader(evsel, leader)) {
                                list_del_init(&evsel->core.node);
                                evlist__add(evlist, evsel);
                        }
                }
        }
}

int __evlist__set_tracepoints_handlers(struct evlist *evlist,
                                       const struct evsel_str_handler *assocs, size_t nr_assocs)
{
        size_t i;
        int err;

        for (i = 0; i < nr_assocs; i++) {
                // Adding a handler for an event not in this evlist, just ignore it.
                struct evsel *evsel = evlist__find_tracepoint_by_name(evlist, assocs[i].name);
                if (evsel == NULL)
                        continue;

                err = -EEXIST;
                if (evsel->handler != NULL)
                        goto out;
                evsel->handler = assocs[i].handler;
        }

        err = 0;
out:
        return err;
}

static void evlist__set_leader(struct evlist *evlist)
{
        perf_evlist__set_leader(&evlist->core);
}

static struct evsel *evlist__dummy_event(struct evlist *evlist)
{
        struct perf_event_attr attr = {
                .type   = PERF_TYPE_SOFTWARE,
                .config = PERF_COUNT_SW_DUMMY,
                .size   = sizeof(attr), /* to capture ABI version */
                /* Avoid frequency mode for dummy events to avoid associated timers. */
                .freq = 0,
                .sample_period = 1,
        };

        return evsel__new_idx(&attr, evlist->core.nr_entries);
}

int evlist__add_dummy(struct evlist *evlist)
{
        struct evsel *evsel = evlist__dummy_event(evlist);

        if (evsel == NULL)
                return -ENOMEM;

        evlist__add(evlist, evsel);
        return 0;
}

struct evsel *evlist__add_aux_dummy(struct evlist *evlist, bool system_wide)
{
        struct evsel *evsel = evlist__dummy_event(evlist);

        if (!evsel)
                return NULL;

        evsel->core.attr.exclude_kernel = 1;
        evsel->core.attr.exclude_guest = 1;
        evsel->core.attr.exclude_hv = 1;
        evsel->core.system_wide = system_wide;
        evsel->no_aux_samples = true;
        evsel->name = strdup("dummy:u");

        evlist__add(evlist, evsel);
        return evsel;
}

#ifdef HAVE_LIBTRACEEVENT
struct evsel *evlist__add_sched_switch(struct evlist *evlist, bool system_wide)
{
        struct evsel *evsel = evsel__newtp_idx("sched", "sched_switch", 0,
                                               /*format=*/true);

        if (IS_ERR(evsel))
                return evsel;

        evsel__set_sample_bit(evsel, CPU);
        evsel__set_sample_bit(evsel, TIME);

        evsel->core.system_wide = system_wide;
        evsel->no_aux_samples = true;

        evlist__add(evlist, evsel);
        return evsel;
}
#endif

struct evsel *evlist__find_tracepoint_by_name(struct evlist *evlist, const char *name)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if ((evsel->core.attr.type == PERF_TYPE_TRACEPOINT) &&
                    (strcmp(evsel->name, name) == 0))
                        return evsel;
        }

        return NULL;
}

#ifdef HAVE_LIBTRACEEVENT
int evlist__add_newtp(struct evlist *evlist, const char *sys, const char *name, void *handler)
{
        struct evsel *evsel = evsel__newtp(sys, name);

        if (IS_ERR(evsel))
                return -1;

        evsel->handler = handler;
        evlist__add(evlist, evsel);
        return 0;
}
#endif

/*
 * Should sched_setaffinity be used with evlist__for_each_cpu? Determine if
 * migrating the thread will avoid possibly numerous IPIs.
 */
static bool evlist__use_affinity(struct evlist *evlist)
{
        struct evsel *pos;
        struct perf_cpu_map *used_cpus = NULL;
        bool ret = false;

        if (evlist->no_affinity || !evlist->core.user_requested_cpus ||
            cpu_map__is_dummy(evlist->core.user_requested_cpus))
                return false;

        evlist__for_each_entry(evlist, pos) {
                struct perf_cpu_map *intersect;

                if (!perf_pmu__benefits_from_affinity(pos->pmu))
                        continue;

                if (evsel__is_dummy_event(pos)) {
                        /*
                         * The dummy event is opened on all CPUs so assume >1
                         * event with shared CPUs.
                         */
                        ret = true;
                        break;
                }
                if (evsel__is_retire_lat(pos)) {
                        /*
                         * Retirement latency events are similar to tool ones in
                         * their implementation, and so don't require affinity.
                         */
                        continue;
                }
                if (perf_cpu_map__is_empty(used_cpus)) {
                        /* First benefitting event, we want >1 on a common CPU. */
                        used_cpus = perf_cpu_map__get(pos->core.cpus);
                        continue;
                }
                if ((pos->core.attr.read_format & PERF_FORMAT_GROUP) &&
                    evsel__leader(pos) != pos) {
                        /* Skip members of the same sample group. */
                        continue;
                }
                intersect = perf_cpu_map__intersect(used_cpus, pos->core.cpus);
                if (!perf_cpu_map__is_empty(intersect)) {
                        /* >1 event with shared CPUs. */
                        perf_cpu_map__put(intersect);
                        ret = true;
                        break;
                }
                perf_cpu_map__put(intersect);
                perf_cpu_map__merge(&used_cpus, pos->core.cpus);
        }
        perf_cpu_map__put(used_cpus);
        return ret;
}

void evlist_cpu_iterator__init(struct evlist_cpu_iterator *itr, struct evlist *evlist)
{
        *itr = (struct evlist_cpu_iterator){
                .container = evlist,
                .evsel = NULL,
                .cpu_map_idx = 0,
                .evlist_cpu_map_idx = 0,
                .evlist_cpu_map_nr = perf_cpu_map__nr(evlist->core.all_cpus),
                .cpu = (struct perf_cpu){ .cpu = -1},
                .affinity = NULL,
        };

        if (evlist__empty(evlist)) {
                /* Ensure the empty list doesn't iterate. */
                itr->evlist_cpu_map_idx = itr->evlist_cpu_map_nr;
                return;
        }

        if (evlist__use_affinity(evlist)) {
                if (affinity__setup(&itr->saved_affinity) == 0)
                        itr->affinity = &itr->saved_affinity;
        }
        itr->evsel = evlist__first(evlist);
        itr->cpu = perf_cpu_map__cpu(evlist->core.all_cpus, 0);
        if (itr->affinity)
                affinity__set(itr->affinity, itr->cpu.cpu);
        itr->cpu_map_idx = perf_cpu_map__idx(itr->evsel->core.cpus, itr->cpu);
        /*
         * If this CPU isn't in the evsel's cpu map then advance
         * through the list.
         */
        if (itr->cpu_map_idx == -1)
                evlist_cpu_iterator__next(itr);
}

void evlist_cpu_iterator__exit(struct evlist_cpu_iterator *itr)
{
        if (!itr->affinity)
                return;

        affinity__cleanup(itr->affinity);
        itr->affinity = NULL;
}

void evlist_cpu_iterator__next(struct evlist_cpu_iterator *evlist_cpu_itr)
{
        while (evlist_cpu_itr->evsel != evlist__last(evlist_cpu_itr->container)) {
                evlist_cpu_itr->evsel = evsel__next(evlist_cpu_itr->evsel);
                evlist_cpu_itr->cpu_map_idx =
                        perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
                                          evlist_cpu_itr->cpu);
                if (evlist_cpu_itr->cpu_map_idx != -1)
                        return;
        }
        evlist_cpu_itr->evlist_cpu_map_idx++;
        if (evlist_cpu_itr->evlist_cpu_map_idx < evlist_cpu_itr->evlist_cpu_map_nr) {
                evlist_cpu_itr->evsel = evlist__first(evlist_cpu_itr->container);
                evlist_cpu_itr->cpu =
                        perf_cpu_map__cpu(evlist_cpu_itr->container->core.all_cpus,
                                          evlist_cpu_itr->evlist_cpu_map_idx);
                if (evlist_cpu_itr->affinity)
                        affinity__set(evlist_cpu_itr->affinity, evlist_cpu_itr->cpu.cpu);
                evlist_cpu_itr->cpu_map_idx =
                        perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
                                          evlist_cpu_itr->cpu);
                /*
                 * If this CPU isn't in the evsel's cpu map then advance through
                 * the list.
                 */
                if (evlist_cpu_itr->cpu_map_idx == -1)
                        evlist_cpu_iterator__next(evlist_cpu_itr);
        } else {
                evlist_cpu_iterator__exit(evlist_cpu_itr);
        }
}

static int evsel__strcmp(struct evsel *pos, char *evsel_name)
{
        if (!evsel_name)
                return 0;
        if (evsel__is_dummy_event(pos))
                return 1;
        return !evsel__name_is(pos, evsel_name);
}

static int evlist__is_enabled(struct evlist *evlist)
{
        struct evsel *pos;

        evlist__for_each_entry(evlist, pos) {
                if (!evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
                /* If at least one event is enabled, evlist is enabled. */
                if (!pos->disabled)
                        return true;
        }
        return false;
}

static void __evlist__disable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
{
        struct evsel *pos;
        struct evlist_cpu_iterator evlist_cpu_itr;
        bool has_imm = false;

        /* Disable 'immediate' events last */
        for (int imm = 0; imm <= 1; imm++) {
                evlist__for_each_cpu(evlist_cpu_itr, evlist) {
                        pos = evlist_cpu_itr.evsel;
                        if (evsel__strcmp(pos, evsel_name))
                                continue;
                        if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
                                continue;
                        if (excl_dummy && evsel__is_dummy_event(pos))
                                continue;
                        if (pos->immediate)
                                has_imm = true;
                        if (pos->immediate != imm)
                                continue;
                        evsel__disable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
                }
                if (!has_imm)
                        break;
        }

        evlist__for_each_entry(evlist, pos) {
                if (evsel__strcmp(pos, evsel_name))
                        continue;
                if (!evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
                if (excl_dummy && evsel__is_dummy_event(pos))
                        continue;
                pos->disabled = true;
        }

        /*
         * If we disabled only single event, we need to check
         * the enabled state of the evlist manually.
         */
        if (evsel_name)
                evlist->enabled = evlist__is_enabled(evlist);
        else
                evlist->enabled = false;
}

void evlist__disable(struct evlist *evlist)
{
        __evlist__disable(evlist, NULL, false);
}

void evlist__disable_non_dummy(struct evlist *evlist)
{
        __evlist__disable(evlist, NULL, true);
}

void evlist__disable_evsel(struct evlist *evlist, char *evsel_name)
{
        __evlist__disable(evlist, evsel_name, false);
}

static void __evlist__enable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
{
        struct evsel *pos;
        struct evlist_cpu_iterator evlist_cpu_itr;

        evlist__for_each_cpu(evlist_cpu_itr, evlist) {
                pos = evlist_cpu_itr.evsel;
                if (evsel__strcmp(pos, evsel_name))
                        continue;
                if (!evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
                if (excl_dummy && evsel__is_dummy_event(pos))
                        continue;
                evsel__enable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
        }
        evlist__for_each_entry(evlist, pos) {
                if (evsel__strcmp(pos, evsel_name))
                        continue;
                if (!evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
                if (excl_dummy && evsel__is_dummy_event(pos))
                        continue;
                pos->disabled = false;
        }

        /*
         * Even single event sets the 'enabled' for evlist,
         * so the toggle can work properly and toggle to
         * 'disabled' state.
         */
        evlist->enabled = true;
}

void evlist__enable(struct evlist *evlist)
{
        __evlist__enable(evlist, NULL, false);
}

void evlist__enable_non_dummy(struct evlist *evlist)
{
        __evlist__enable(evlist, NULL, true);
}

void evlist__enable_evsel(struct evlist *evlist, char *evsel_name)
{
        __evlist__enable(evlist, evsel_name, false);
}

void evlist__toggle_enable(struct evlist *evlist)
{
        (evlist->enabled ? evlist__disable : evlist__enable)(evlist);
}

int evlist__add_pollfd(struct evlist *evlist, int fd)
{
        return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN, fdarray_flag__default);
}

int evlist__filter_pollfd(struct evlist *evlist, short revents_and_mask)
{
        return perf_evlist__filter_pollfd(&evlist->core, revents_and_mask);
}

#ifdef HAVE_EVENTFD_SUPPORT
int evlist__add_wakeup_eventfd(struct evlist *evlist, int fd)
{
        return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
                                       fdarray_flag__nonfilterable |
                                       fdarray_flag__non_perf_event);
}
#endif

int evlist__poll(struct evlist *evlist, int timeout)
{
        return perf_evlist__poll(&evlist->core, timeout);
}

struct perf_sample_id *evlist__id2sid(struct evlist *evlist, u64 id)
{
        struct hlist_head *head;
        struct perf_sample_id *sid;
        int hash;

        hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
        head = &evlist->core.heads[hash];

        hlist_for_each_entry(sid, head, node)
                if (sid->id == id)
                        return sid;

        return NULL;
}

struct evsel *evlist__id2evsel(struct evlist *evlist, u64 id)
{
        struct perf_sample_id *sid;

        if (evlist->core.nr_entries == 1 || !id)
                return evlist__first(evlist);

        sid = evlist__id2sid(evlist, id);
        if (sid)
                return container_of(sid->evsel, struct evsel, core);

        if (!evlist__sample_id_all(evlist))
                return evlist__first(evlist);

        return NULL;
}

struct evsel *evlist__id2evsel_strict(struct evlist *evlist, u64 id)
{
        struct perf_sample_id *sid;

        if (!id)
                return NULL;

        sid = evlist__id2sid(evlist, id);
        if (sid)
                return container_of(sid->evsel, struct evsel, core);

        return NULL;
}

static int evlist__event2id(struct evlist *evlist, union perf_event *event, u64 *id)
{
        const __u64 *array = event->sample.array;
        ssize_t n;

        n = (event->header.size - sizeof(event->header)) >> 3;

        if (event->header.type == PERF_RECORD_SAMPLE) {
                if (evlist->id_pos >= n)
                        return -1;
                *id = array[evlist->id_pos];
        } else {
                if (evlist->is_pos > n)
                        return -1;
                n -= evlist->is_pos;
                *id = array[n];
        }
        return 0;
}

struct evsel *evlist__event2evsel(struct evlist *evlist, union perf_event *event)
{
        struct evsel *first = evlist__first(evlist);
        struct hlist_head *head;
        struct perf_sample_id *sid;
        int hash;
        u64 id;

        if (evlist->core.nr_entries == 1)
                return first;

        if (!first->core.attr.sample_id_all &&
            event->header.type != PERF_RECORD_SAMPLE)
                return first;

        if (evlist__event2id(evlist, event, &id))
                return NULL;

        /* Synthesized events have an id of zero */
        if (!id)
                return first;

        hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
        head = &evlist->core.heads[hash];

        hlist_for_each_entry(sid, head, node) {
                if (sid->id == id)
                        return container_of(sid->evsel, struct evsel, core);
        }
        return NULL;
}

static int evlist__set_paused(struct evlist *evlist, bool value)
{
        int i;

        if (!evlist->overwrite_mmap)
                return 0;

        for (i = 0; i < evlist->core.nr_mmaps; i++) {
                int fd = evlist->overwrite_mmap[i].core.fd;
                int err;

                if (fd < 0)
                        continue;
                err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
                if (err)
                        return err;
        }
        return 0;
}

static int evlist__pause(struct evlist *evlist)
{
        return evlist__set_paused(evlist, true);
}

static int evlist__resume(struct evlist *evlist)
{
        return evlist__set_paused(evlist, false);
}

static void evlist__munmap_nofree(struct evlist *evlist)
{
        int i;

        if (evlist->mmap)
                for (i = 0; i < evlist->core.nr_mmaps; i++)
                        perf_mmap__munmap(&evlist->mmap[i].core);

        if (evlist->overwrite_mmap)
                for (i = 0; i < evlist->core.nr_mmaps; i++)
                        perf_mmap__munmap(&evlist->overwrite_mmap[i].core);
}

void evlist__munmap(struct evlist *evlist)
{
        evlist__munmap_nofree(evlist);
        zfree(&evlist->mmap);
        zfree(&evlist->overwrite_mmap);
}

static void perf_mmap__unmap_cb(struct perf_mmap *map)
{
        struct mmap *m = container_of(map, struct mmap, core);

        mmap__munmap(m);
}

static struct mmap *evlist__alloc_mmap(struct evlist *evlist,
                                       bool overwrite)
{
        int i;
        struct mmap *map;

        map = zalloc(evlist->core.nr_mmaps * sizeof(struct mmap));
        if (!map)
                return NULL;

        for (i = 0; i < evlist->core.nr_mmaps; i++) {
                struct perf_mmap *prev = i ? &map[i - 1].core : NULL;

                /*
                 * When the perf_mmap() call is made we grab one refcount, plus
                 * one extra to let perf_mmap__consume() get the last
                 * events after all real references (perf_mmap__get()) are
                 * dropped.
                 *
                 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
                 * thus does perf_mmap__get() on it.
                 */
                perf_mmap__init(&map[i].core, prev, overwrite, perf_mmap__unmap_cb);
        }

        return map;
}

static void
perf_evlist__mmap_cb_idx(struct perf_evlist *_evlist,
                         struct perf_evsel *_evsel,
                         struct perf_mmap_param *_mp,
                         int idx)
{
        struct evlist *evlist = container_of(_evlist, struct evlist, core);
        struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
        struct evsel *evsel = container_of(_evsel, struct evsel, core);

        auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, evsel, idx);
}

static struct perf_mmap*
perf_evlist__mmap_cb_get(struct perf_evlist *_evlist, bool overwrite, int idx)
{
        struct evlist *evlist = container_of(_evlist, struct evlist, core);
        struct mmap *maps;

        maps = overwrite ? evlist->overwrite_mmap : evlist->mmap;

        if (!maps) {
                maps = evlist__alloc_mmap(evlist, overwrite);
                if (!maps)
                        return NULL;

                if (overwrite) {
                        evlist->overwrite_mmap = maps;
                        if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
                                evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
                } else {
                        evlist->mmap = maps;
                }
        }

        return &maps[idx].core;
}

static int
perf_evlist__mmap_cb_mmap(struct perf_mmap *_map, struct perf_mmap_param *_mp,
                          int output, struct perf_cpu cpu)
{
        struct mmap *map = container_of(_map, struct mmap, core);
        struct mmap_params *mp = container_of(_mp, struct mmap_params, core);

        return mmap__mmap(map, mp, output, cpu);
}

unsigned long perf_event_mlock_kb_in_pages(void)
{
        unsigned long pages;
        int max;

        if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
                /*
                 * Pick a once upon a time good value, i.e. things look
                 * strange since we can't read a sysctl value, but lets not
                 * die yet...
                 */
                max = 512;
        } else {
                max -= (page_size / 1024);
        }

        pages = (max * 1024) / page_size;
        if (!is_power_of_2(pages))
                pages = rounddown_pow_of_two(pages);

        return pages;
}

size_t evlist__mmap_size(unsigned long pages)
{
        if (pages == UINT_MAX)
                pages = perf_event_mlock_kb_in_pages();
        else if (!is_power_of_2(pages))
                return 0;

        return (pages + 1) * page_size;
}

static long parse_pages_arg(const char *str, unsigned long min,
                            unsigned long max)
{
        unsigned long pages, val;
        static struct parse_tag tags[] = {
                { .tag  = 'B', .mult = 1       },
                { .tag  = 'K', .mult = 1 << 10 },
                { .tag  = 'M', .mult = 1 << 20 },
                { .tag  = 'G', .mult = 1 << 30 },
                { .tag  = 0 },
        };

        if (str == NULL)
                return -EINVAL;

        val = parse_tag_value(str, tags);
        if (val != (unsigned long) -1) {
                /* we got file size value */
                pages = PERF_ALIGN(val, page_size) / page_size;
        } else {
                /* we got pages count value */
                char *eptr;
                pages = strtoul(str, &eptr, 10);
                if (*eptr != '\0')
                        return -EINVAL;
        }

        if (pages == 0 && min == 0) {
                /* leave number of pages at 0 */
        } else if (!is_power_of_2(pages)) {
                char buf[100];

                /* round pages up to next power of 2 */
                pages = roundup_pow_of_two(pages);
                if (!pages)
                        return -EINVAL;

                unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
                pr_info("rounding mmap pages size to %s (%lu pages)\n",
                        buf, pages);
        }

        if (pages > max)
                return -EINVAL;

        return pages;
}

int __evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
{
        unsigned long max = UINT_MAX;
        long pages;

        if (max > SIZE_MAX / page_size)
                max = SIZE_MAX / page_size;

        pages = parse_pages_arg(str, 1, max);
        if (pages < 0) {
                pr_err("Invalid argument for --mmap_pages/-m\n");
                return -1;
        }

        *mmap_pages = pages;
        return 0;
}

int evlist__parse_mmap_pages(const struct option *opt, const char *str, int unset __maybe_unused)
{
        return __evlist__parse_mmap_pages(opt->value, str);
}

/**
 * evlist__mmap_ex - Create mmaps to receive events.
 * @evlist: list of events
 * @pages: map length in pages
 * @overwrite: overwrite older events?
 * @auxtrace_pages - auxtrace map length in pages
 * @auxtrace_overwrite - overwrite older auxtrace data?
 *
 * If @overwrite is %false the user needs to signal event consumption using
 * perf_mmap__write_tail().  Using evlist__mmap_read() does this
 * automatically.
 *
 * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
 * consumption using auxtrace_mmap__write_tail().
 *
 * Return: %0 on success, negative error code otherwise.
 */
int evlist__mmap_ex(struct evlist *evlist, unsigned int pages,
                         unsigned int auxtrace_pages,
                         bool auxtrace_overwrite, int nr_cblocks, int affinity, int flush,
                         int comp_level)
{
        /*
         * Delay setting mp.prot: set it before calling perf_mmap__mmap.
         * Its value is decided by evsel's write_backward.
         * So &mp should not be passed through const pointer.
         */
        struct mmap_params mp = {
                .nr_cblocks     = nr_cblocks,
                .affinity       = affinity,
                .flush          = flush,
                .comp_level     = comp_level
        };
        struct perf_evlist_mmap_ops ops = {
                .idx  = perf_evlist__mmap_cb_idx,
                .get  = perf_evlist__mmap_cb_get,
                .mmap = perf_evlist__mmap_cb_mmap,
        };

        evlist->core.mmap_len = evlist__mmap_size(pages);
        pr_debug("mmap size %zuB\n", evlist->core.mmap_len);

        auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->core.mmap_len,
                                   auxtrace_pages, auxtrace_overwrite);

        return perf_evlist__mmap_ops(&evlist->core, &ops, &mp.core);
}

int evlist__mmap(struct evlist *evlist, unsigned int pages)
{
        return evlist__mmap_ex(evlist, pages, 0, false, 0, PERF_AFFINITY_SYS, 1, 0);
}

int evlist__create_maps(struct evlist *evlist, struct target *target)
{
        bool all_threads = (target->per_thread && target->system_wide);
        struct perf_cpu_map *cpus;
        struct perf_thread_map *threads;

        /*
         * If specify '-a' and '--per-thread' to perf record, perf record
         * will override '--per-thread'. target->per_thread = false and
         * target->system_wide = true.
         *
         * If specify '--per-thread' only to perf record,
         * target->per_thread = true and target->system_wide = false.
         *
         * So target->per_thread && target->system_wide is false.
         * For perf record, thread_map__new_str doesn't call
         * thread_map__new_all_cpus. That will keep perf record's
         * current behavior.
         *
         * For perf stat, it allows the case that target->per_thread and
         * target->system_wide are all true. It means to collect system-wide
         * per-thread data. thread_map__new_str will call
         * thread_map__new_all_cpus to enumerate all threads.
         */
        threads = thread_map__new_str(target->pid, target->tid, all_threads);

        if (!threads)
                return -1;

        if (target__uses_dummy_map(target) && !evlist__has_bpf_output(evlist))
                cpus = perf_cpu_map__new_any_cpu();
        else
                cpus = perf_cpu_map__new(target->cpu_list);

        if (!cpus)
                goto out_delete_threads;

        evlist->core.has_user_cpus = !!target->cpu_list;

        perf_evlist__set_maps(&evlist->core, cpus, threads);

        /* as evlist now has references, put count here */
        perf_cpu_map__put(cpus);
        perf_thread_map__put(threads);

        return 0;

out_delete_threads:
        perf_thread_map__put(threads);
        return -1;
}

int evlist__apply_filters(struct evlist *evlist, struct evsel **err_evsel,
                          struct target *target)
{
        struct evsel *evsel;
        int err = 0;

        evlist__for_each_entry(evlist, evsel) {
                /*
                 * filters only work for tracepoint event, which doesn't have cpu limit.
                 * So evlist and evsel should always be same.
                 */
                if (evsel->filter) {
                        err = perf_evsel__apply_filter(&evsel->core, evsel->filter);
                        if (err) {
                                *err_evsel = evsel;
                                break;
                        }
                }

                /*
                 * non-tracepoint events can have BPF filters.
                 */
                if (!list_empty(&evsel->bpf_filters)) {
                        err = perf_bpf_filter__prepare(evsel, target);
                        if (err) {
                                *err_evsel = evsel;
                                break;
                        }
                }
        }

        return err;
}

int evlist__set_tp_filter(struct evlist *evlist, const char *filter)
{
        struct evsel *evsel;
        int err = 0;

        if (filter == NULL)
                return -1;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
                        continue;

                err = evsel__set_filter(evsel, filter);
                if (err)
                        break;
        }

        return err;
}

int evlist__append_tp_filter(struct evlist *evlist, const char *filter)
{
        struct evsel *evsel;
        int err = 0;

        if (filter == NULL)
                return -1;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
                        continue;

                err = evsel__append_tp_filter(evsel, filter);
                if (err)
                        break;
        }

        return err;
}

char *asprintf__tp_filter_pids(size_t npids, pid_t *pids)
{
        char *filter;
        size_t i;

        for (i = 0; i < npids; ++i) {
                if (i == 0) {
                        if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
                                return NULL;
                } else {
                        char *tmp;

                        if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
                                goto out_free;

                        free(filter);
                        filter = tmp;
                }
        }

        return filter;
out_free:
        free(filter);
        return NULL;
}

int evlist__set_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
{
        char *filter = asprintf__tp_filter_pids(npids, pids);
        int ret = evlist__set_tp_filter(evlist, filter);

        free(filter);
        return ret;
}

int evlist__append_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
{
        char *filter = asprintf__tp_filter_pids(npids, pids);
        int ret = evlist__append_tp_filter(evlist, filter);

        free(filter);
        return ret;
}

int evlist__append_tp_filter_pid(struct evlist *evlist, pid_t pid)
{
        return evlist__append_tp_filter_pids(evlist, 1, &pid);
}

bool evlist__valid_sample_type(struct evlist *evlist)
{
        struct evsel *pos;

        if (evlist->core.nr_entries == 1)
                return true;

        if (evlist->id_pos < 0 || evlist->is_pos < 0)
                return false;

        evlist__for_each_entry(evlist, pos) {
                if (pos->id_pos != evlist->id_pos ||
                    pos->is_pos != evlist->is_pos)
                        return false;
        }

        return true;
}

u64 __evlist__combined_sample_type(struct evlist *evlist)
{
        struct evsel *evsel;

        if (evlist->combined_sample_type)
                return evlist->combined_sample_type;

        evlist__for_each_entry(evlist, evsel)
                evlist->combined_sample_type |= evsel->core.attr.sample_type;

        return evlist->combined_sample_type;
}

u64 evlist__combined_sample_type(struct evlist *evlist)
{
        evlist->combined_sample_type = 0;
        return __evlist__combined_sample_type(evlist);
}

u64 evlist__combined_branch_type(struct evlist *evlist)
{
        struct evsel *evsel;
        u64 branch_type = 0;

        evlist__for_each_entry(evlist, evsel)
                branch_type |= evsel->core.attr.branch_sample_type;
        return branch_type;
}

static struct evsel *
evlist__find_dup_event_from_prev(struct evlist *evlist, struct evsel *event)
{
        struct evsel *pos;

        evlist__for_each_entry(evlist, pos) {
                if (event == pos)
                        break;
                if ((pos->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) &&
                    !strcmp(pos->name, event->name))
                        return pos;
        }
        return NULL;
}

#define MAX_NR_ABBR_NAME        (26 * 11)

/*
 * The abbr name is from A to Z9. If the number of event
 * which requires the branch counter > MAX_NR_ABBR_NAME,
 * return NA.
 */
static void evlist__new_abbr_name(char *name)
{
        static int idx;
        int i = idx / 26;

        if (idx >= MAX_NR_ABBR_NAME) {
                name[0] = 'N';
                name[1] = 'A';
                name[2] = '\0';
                return;
        }

        name[0] = 'A' + (idx % 26);

        if (!i)
                name[1] = '\0';
        else {
                name[1] = '0' + i - 1;
                name[2] = '\0';
        }

        idx++;
}

void evlist__update_br_cntr(struct evlist *evlist)
{
        struct evsel *evsel, *dup;
        int i = 0;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) {
                        evsel->br_cntr_idx = i++;
                        evsel__leader(evsel)->br_cntr_nr++;

                        dup = evlist__find_dup_event_from_prev(evlist, evsel);
                        if (dup)
                                memcpy(evsel->abbr_name, dup->abbr_name, 3 * sizeof(char));
                        else
                                evlist__new_abbr_name(evsel->abbr_name);
                }
        }
        evlist->nr_br_cntr = i;
}

bool evlist__valid_read_format(struct evlist *evlist)
{
        struct evsel *first = evlist__first(evlist), *pos = first;
        u64 read_format = first->core.attr.read_format;
        u64 sample_type = first->core.attr.sample_type;

        evlist__for_each_entry(evlist, pos) {
                if (read_format != pos->core.attr.read_format) {
                        pr_debug("Read format differs %#" PRIx64 " vs %#" PRIx64 "\n",
                                 read_format, (u64)pos->core.attr.read_format);
                }
        }

        /* PERF_SAMPLE_READ implies PERF_FORMAT_ID. */
        if ((sample_type & PERF_SAMPLE_READ) &&
            !(read_format & PERF_FORMAT_ID)) {
                return false;
        }

        return true;
}

u16 evlist__id_hdr_size(struct evlist *evlist)
{
        struct evsel *first = evlist__first(evlist);

        return first->core.attr.sample_id_all ? evsel__id_hdr_size(first) : 0;
}

bool evlist__valid_sample_id_all(struct evlist *evlist)
{
        struct evsel *first = evlist__first(evlist), *pos = first;

        evlist__for_each_entry_continue(evlist, pos) {
                if (first->core.attr.sample_id_all != pos->core.attr.sample_id_all)
                        return false;
        }

        return true;
}

bool evlist__sample_id_all(struct evlist *evlist)
{
        struct evsel *first = evlist__first(evlist);
        return first->core.attr.sample_id_all;
}

void evlist__set_selected(struct evlist *evlist, struct evsel *evsel)
{
        evlist->selected = evsel;
}

void evlist__close(struct evlist *evlist)
{
        struct evsel *evsel;
        struct evlist_cpu_iterator evlist_cpu_itr;

        evlist__for_each_cpu(evlist_cpu_itr, evlist) {
                if (evlist_cpu_itr.cpu_map_idx == 0 && evsel__is_retire_lat(evlist_cpu_itr.evsel))
                        evsel__tpebs_close(evlist_cpu_itr.evsel);
                perf_evsel__close_cpu(&evlist_cpu_itr.evsel->core,
                                      evlist_cpu_itr.cpu_map_idx);
        }

        evlist__for_each_entry_reverse(evlist, evsel) {
                perf_evsel__free_fd(&evsel->core);
                perf_evsel__free_id(&evsel->core);
        }
        perf_evlist__reset_id_hash(&evlist->core);
}

static int evlist__create_syswide_maps(struct evlist *evlist)
{
        struct perf_cpu_map *cpus;
        struct perf_thread_map *threads;

        /*
         * Try reading /sys/devices/system/cpu/online to get
         * an all cpus map.
         *
         * FIXME: -ENOMEM is the best we can do here, the cpu_map
         * code needs an overhaul to properly forward the
         * error, and we may not want to do that fallback to a
         * default cpu identity map :-\
         */
        cpus = perf_cpu_map__new_online_cpus();
        if (!cpus)
                return -ENOMEM;

        threads = perf_thread_map__new_dummy();
        if (!threads) {
                perf_cpu_map__put(cpus);
                return -ENOMEM;
        }

        perf_evlist__set_maps(&evlist->core, cpus, threads);
        perf_thread_map__put(threads);
        perf_cpu_map__put(cpus);
        return 0;
}

int evlist__open(struct evlist *evlist)
{
        struct evsel *evsel;
        int err;

        /*
         * Default: one fd per CPU, all threads, aka systemwide
         * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
         */
        if (evlist->core.threads == NULL && evlist->core.user_requested_cpus == NULL) {
                err = evlist__create_syswide_maps(evlist);
                if (err < 0)
                        goto out_err;
        }

        evlist__update_id_pos(evlist);

        evlist__for_each_entry(evlist, evsel) {
                err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
                if (err < 0)
                        goto out_err;
        }

        return 0;
out_err:
        evlist__close(evlist);
        errno = -err;
        return err;
}

int evlist__prepare_workload(struct evlist *evlist, struct target *target, const char *argv[],
                             bool pipe_output, void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
{
        int child_ready_pipe[2], go_pipe[2];
        char bf;

        evlist->workload.cork_fd = -1;

        if (pipe(child_ready_pipe) < 0) {
                perror("failed to create 'ready' pipe");
                return -1;
        }

        if (pipe(go_pipe) < 0) {
                perror("failed to create 'go' pipe");
                goto out_close_ready_pipe;
        }

        evlist->workload.pid = fork();
        if (evlist->workload.pid < 0) {
                perror("failed to fork");
                goto out_close_pipes;
        }

        if (!evlist->workload.pid) {
                int ret;

                if (pipe_output)
                        dup2(2, 1);

                signal(SIGTERM, SIG_DFL);

                close(child_ready_pipe[0]);
                close(go_pipe[1]);
                fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);

                /*
                 * Change the name of this process not to confuse --exclude-perf users
                 * that sees 'perf' in the window up to the execvp() and thinks that
                 * perf samples are not being excluded.
                 */
                prctl(PR_SET_NAME, "perf-exec");

                /*
                 * Tell the parent we're ready to go
                 */
                close(child_ready_pipe[1]);

                /*
                 * Wait until the parent tells us to go.
                 */
                ret = read(go_pipe[0], &bf, 1);
                /*
                 * The parent will ask for the execvp() to be performed by
                 * writing exactly one byte, in workload.cork_fd, usually via
                 * evlist__start_workload().
                 *
                 * For cancelling the workload without actually running it,
                 * the parent will just close workload.cork_fd, without writing
                 * anything, i.e. read will return zero and we just exit()
                 * here (See evlist__cancel_workload()).
                 */
                if (ret != 1) {
                        if (ret == -1)
                                perror("unable to read pipe");
                        exit(ret);
                }

                execvp(argv[0], (char **)argv);

                if (exec_error) {
                        union sigval val;

                        val.sival_int = errno;
                        if (sigqueue(getppid(), SIGUSR1, val))
                                perror(argv[0]);
                } else
                        perror(argv[0]);
                exit(-1);
        }

        if (exec_error) {
                struct sigaction act = {
                        .sa_flags     = SA_SIGINFO,
                        .sa_sigaction = exec_error,
                };
                sigaction(SIGUSR1, &act, NULL);
        }

        if (target__none(target)) {
                if (evlist->core.threads == NULL) {
                        fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
                                __func__, __LINE__);
                        goto out_close_pipes;
                }
                perf_thread_map__set_pid(evlist->core.threads, 0, evlist->workload.pid);
        }

        close(child_ready_pipe[1]);
        close(go_pipe[0]);
        /*
         * wait for child to settle
         */
        if (read(child_ready_pipe[0], &bf, 1) == -1) {
                perror("unable to read pipe");
                goto out_close_pipes;
        }

        fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
        evlist->workload.cork_fd = go_pipe[1];
        close(child_ready_pipe[0]);
        return 0;

out_close_pipes:
        close(go_pipe[0]);
        close(go_pipe[1]);
out_close_ready_pipe:
        close(child_ready_pipe[0]);
        close(child_ready_pipe[1]);
        return -1;
}

int evlist__start_workload(struct evlist *evlist)
{
        if (evlist->workload.cork_fd >= 0) {
                char bf = 0;
                int ret;
                /*
                 * Remove the cork, let it rip!
                 */
                ret = write(evlist->workload.cork_fd, &bf, 1);
                if (ret < 0)
                        perror("unable to write to pipe");

                close(evlist->workload.cork_fd);
                evlist->workload.cork_fd = -1;
                return ret;
        }

        return 0;
}

void evlist__cancel_workload(struct evlist *evlist)
{
        int status;

        if (evlist->workload.cork_fd >= 0) {
                close(evlist->workload.cork_fd);
                evlist->workload.cork_fd = -1;
                waitpid(evlist->workload.pid, &status, WNOHANG);
        }
}

int evlist__parse_sample(struct evlist *evlist, union perf_event *event, struct perf_sample *sample)
{
        struct evsel *evsel = evlist__event2evsel(evlist, event);
        int ret;

        if (!evsel)
                return -EFAULT;
        ret = evsel__parse_sample(evsel, event, sample);
        if (ret)
                return ret;
        if (perf_guest && sample->id) {
                struct perf_sample_id *sid = evlist__id2sid(evlist, sample->id);

                if (sid) {
                        sample->machine_pid = sid->machine_pid;
                        sample->vcpu = sid->vcpu.cpu;
                }
        }
        return 0;
}

int evlist__parse_sample_timestamp(struct evlist *evlist, union perf_event *event, u64 *timestamp)
{
        struct evsel *evsel = evlist__event2evsel(evlist, event);

        if (!evsel)
                return -EFAULT;
        return evsel__parse_sample_timestamp(evsel, event, timestamp);
}

int evlist__strerror_open(struct evlist *evlist, int err, char *buf, size_t size)
{
        int printed, value;

        switch (err) {
        case EACCES:
        case EPERM:
                errno = err;
                printed = scnprintf(buf, size,
                                    "Error:\t%m.\n"
                                    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.");

                value = perf_event_paranoid();

                printed += scnprintf(buf + printed, size - printed, "\nHint:\t");

                if (value >= 2) {
                        printed += scnprintf(buf + printed, size - printed,
                                             "For your workloads it needs to be <= 1\nHint:\t");
                }
                printed += scnprintf(buf + printed, size - printed,
                                     "For system wide tracing it needs to be set to -1.\n");

                printed += scnprintf(buf + printed, size - printed,
                                    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
                                    "Hint:\tThe current value is %d.", value);
                break;
        case EINVAL: {
                struct evsel *first = evlist__first(evlist);
                int max_freq;

                if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
                        goto out_default;

                if (first->core.attr.sample_freq < (u64)max_freq)
                        goto out_default;

                errno = err;
                printed = scnprintf(buf, size,
                                    "Error:\t%m.\n"
                                    "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
                                    "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
                                    max_freq, first->core.attr.sample_freq);
                break;
        }
        default:
out_default:
                errno = err;
                scnprintf(buf, size, "%m");
                break;
        }

        return 0;
}

int evlist__strerror_mmap(struct evlist *evlist, int err, char *buf, size_t size)
{
        int pages_attempted = evlist->core.mmap_len / 1024, pages_max_per_user, printed = 0;

        switch (err) {
        case EPERM:
                sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
                errno = err;
                printed += scnprintf(buf + printed, size - printed,
                                     "Error:\t%m.\n"
                                     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
                                     "Hint:\tTried using %zd kB.\n",
                                     pages_max_per_user, pages_attempted);

                if (pages_attempted >= pages_max_per_user) {
                        printed += scnprintf(buf + printed, size - printed,
                                             "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
                                             pages_max_per_user + pages_attempted);
                }

                printed += scnprintf(buf + printed, size - printed,
                                     "Hint:\tTry using a smaller -m/--mmap-pages value.");
                break;
        default:
                errno = err;
                scnprintf(buf, size, "%m");
                break;
        }

        return 0;
}

void evlist__to_front(struct evlist *evlist, struct evsel *move_evsel)
{
        struct evsel *evsel, *n;
        LIST_HEAD(move);

        if (move_evsel == evlist__first(evlist))
                return;

        evlist__for_each_entry_safe(evlist, n, evsel) {
                if (evsel__leader(evsel) == evsel__leader(move_evsel))
                        list_move_tail(&evsel->core.node, &move);
        }

        list_splice(&move, &evlist->core.entries);
}

struct evsel *evlist__get_tracking_event(struct evlist *evlist)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->tracking)
                        return evsel;
        }

        return evlist__first(evlist);
}

void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel)
{
        struct evsel *evsel;

        if (tracking_evsel->tracking)
                return;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel != tracking_evsel)
                        evsel->tracking = false;
        }

        tracking_evsel->tracking = true;
}

struct evsel *evlist__findnew_tracking_event(struct evlist *evlist, bool system_wide)
{
        struct evsel *evsel;

        evsel = evlist__get_tracking_event(evlist);
        if (!evsel__is_dummy_event(evsel)) {
                evsel = evlist__add_aux_dummy(evlist, system_wide);
                if (!evsel)
                        return NULL;

                evlist__set_tracking_event(evlist, evsel);
        } else if (system_wide) {
                perf_evlist__go_system_wide(&evlist->core, &evsel->core);
        }

        return evsel;
}

struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (!evsel->name)
                        continue;
                if (evsel__name_is(evsel, str))
                        return evsel;
        }

        return NULL;
}

void evlist__toggle_bkw_mmap(struct evlist *evlist, enum bkw_mmap_state state)
{
        enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
        enum action {
                NONE,
                PAUSE,
                RESUME,
        } action = NONE;

        if (!evlist->overwrite_mmap)
                return;

        switch (old_state) {
        case BKW_MMAP_NOTREADY: {
                if (state != BKW_MMAP_RUNNING)
                        goto state_err;
                break;
        }
        case BKW_MMAP_RUNNING: {
                if (state != BKW_MMAP_DATA_PENDING)
                        goto state_err;
                action = PAUSE;
                break;
        }
        case BKW_MMAP_DATA_PENDING: {
                if (state != BKW_MMAP_EMPTY)
                        goto state_err;
                break;
        }
        case BKW_MMAP_EMPTY: {
                if (state != BKW_MMAP_RUNNING)
                        goto state_err;
                action = RESUME;
                break;
        }
        default:
                WARN_ONCE(1, "Shouldn't get there\n");
        }

        evlist->bkw_mmap_state = state;

        switch (action) {
        case PAUSE:
                evlist__pause(evlist);
                break;
        case RESUME:
                evlist__resume(evlist);
                break;
        case NONE:
        default:
                break;
        }

state_err:
        return;
}

bool evlist__exclude_kernel(struct evlist *evlist)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (!evsel->core.attr.exclude_kernel)
                        return false;
        }

        return true;
}

/*
 * Events in data file are not collect in groups, but we still want
 * the group display. Set the artificial group and set the leader's
 * forced_leader flag to notify the display code.
 */
void evlist__force_leader(struct evlist *evlist)
{
        if (evlist__nr_groups(evlist) == 0) {
                struct evsel *leader = evlist__first(evlist);

                evlist__set_leader(evlist);
                leader->forced_leader = true;
        }
}

struct evsel *evlist__reset_weak_group(struct evlist *evsel_list, struct evsel *evsel, bool close)
{
        struct evsel *c2, *leader;
        bool is_open = true;

        leader = evsel__leader(evsel);

        pr_debug("Weak group for %s/%d failed\n",
                        leader->name, leader->core.nr_members);

        /*
         * for_each_group_member doesn't work here because it doesn't
         * include the first entry.
         */
        evlist__for_each_entry(evsel_list, c2) {
                if (c2 == evsel)
                        is_open = false;
                if (evsel__has_leader(c2, leader)) {
                        if (is_open && close)
                                perf_evsel__close(&c2->core);
                        /*
                         * We want to close all members of the group and reopen
                         * them. Some events, like Intel topdown, require being
                         * in a group and so keep these in the group.
                         */
                        evsel__remove_from_group(c2, leader);

                        /*
                         * Set this for all former members of the group
                         * to indicate they get reopened.
                         */
                        c2->reset_group = true;
                }
        }
        /* Reset the leader count if all entries were removed. */
        if (leader->core.nr_members == 1)
                leader->core.nr_members = 0;
        return leader;
}

static int evlist__parse_control_fifo(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
{
        char *s, *p;
        int ret = 0, fd;

        if (strncmp(str, "fifo:", 5))
                return -EINVAL;

        str += 5;
        if (!*str || *str == ',')
                return -EINVAL;

        s = strdup(str);
        if (!s)
                return -ENOMEM;

        p = strchr(s, ',');
        if (p)
                *p = '\0';

        /*
         * O_RDWR avoids POLLHUPs which is necessary to allow the other
         * end of a FIFO to be repeatedly opened and closed.
         */
        fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC);
        if (fd < 0) {
                ret = -errno;
                pr_err("Failed to open '%s': %m\n", s);
                goto out_free;
        }
        *ctl_fd = fd;
        *ctl_fd_close = true;

        if (p && *++p) {
                /* O_RDWR | O_NONBLOCK means the other end need not be open */
                fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC);
                if (fd < 0) {
                        pr_err("Failed to open '%s': %m\n", p);
                        ret = -errno;
                        goto out_free;
                }
                *ctl_fd_ack = fd;
        }

out_free:
        free(s);
        return ret;
}

int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
{
        const char *comma = NULL;
        char *endptr = NULL;

        *ctl_fd_close = false;

        if (strncmp(str, "fd:", 3))
                return evlist__parse_control_fifo(str, ctl_fd, ctl_fd_ack, ctl_fd_close);

        *ctl_fd = strtoul(&str[3], &endptr, 0);
        if (endptr == &str[3])
                return -EINVAL;

        comma = strchr(str, ',');
        if (comma) {
                if (endptr != comma)
                        return -EINVAL;

                *ctl_fd_ack = strtoul(comma + 1, &endptr, 0);
                if (endptr == comma + 1 || *endptr != '\0')
                        return -EINVAL;
        }

        return 0;
}

void evlist__close_control(int ctl_fd, int ctl_fd_ack, bool *ctl_fd_close)
{
        if (*ctl_fd_close) {
                *ctl_fd_close = false;
                close(ctl_fd);
                if (ctl_fd_ack >= 0)
                        close(ctl_fd_ack);
        }
}

int evlist__initialize_ctlfd(struct evlist *evlist, int fd, int ack)
{
        if (fd == -1) {
                pr_debug("Control descriptor is not initialized\n");
                return 0;
        }

        evlist->ctl_fd.pos = perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
                                                     fdarray_flag__nonfilterable |
                                                     fdarray_flag__non_perf_event);
        if (evlist->ctl_fd.pos < 0) {
                evlist->ctl_fd.pos = -1;
                pr_err("Failed to add ctl fd entry: %m\n");
                return -1;
        }

        evlist->ctl_fd.fd = fd;
        evlist->ctl_fd.ack = ack;

        return 0;
}

bool evlist__ctlfd_initialized(struct evlist *evlist)
{
        return evlist->ctl_fd.pos >= 0;
}

int evlist__finalize_ctlfd(struct evlist *evlist)
{
        struct pollfd *entries = evlist->core.pollfd.entries;

        if (!evlist__ctlfd_initialized(evlist))
                return 0;

        entries[evlist->ctl_fd.pos].fd = -1;
        entries[evlist->ctl_fd.pos].events = 0;
        entries[evlist->ctl_fd.pos].revents = 0;

        evlist->ctl_fd.pos = -1;
        evlist->ctl_fd.ack = -1;
        evlist->ctl_fd.fd = -1;

        return 0;
}

static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd,
                              char *cmd_data, size_t data_size)
{
        int err;
        char c;
        size_t bytes_read = 0;

        *cmd = EVLIST_CTL_CMD_UNSUPPORTED;
        memset(cmd_data, 0, data_size);
        data_size--;

        do {
                err = read(evlist->ctl_fd.fd, &c, 1);
                if (err > 0) {
                        if (c == '\n' || c == '\0')
                                break;
                        cmd_data[bytes_read++] = c;
                        if (bytes_read == data_size)
                                break;
                        continue;
                } else if (err == -1) {
                        if (errno == EINTR)
                                continue;
                        if (errno == EAGAIN || errno == EWOULDBLOCK)
                                err = 0;
                        else
                                pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);
                }
                break;
        } while (1);

        pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,
                 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");

        if (bytes_read > 0) {
                if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,
                             (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_ENABLE;
                } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG,
                                    (sizeof(EVLIST_CTL_CMD_DISABLE_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_DISABLE;
                } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_SNAPSHOT_TAG,
                                    (sizeof(EVLIST_CTL_CMD_SNAPSHOT_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_SNAPSHOT;
                        pr_debug("is snapshot\n");
                } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_EVLIST_TAG,
                                    (sizeof(EVLIST_CTL_CMD_EVLIST_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_EVLIST;
                } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG,
                                    (sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_STOP;
                } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_PING_TAG,
                                    (sizeof(EVLIST_CTL_CMD_PING_TAG)-1))) {
                        *cmd = EVLIST_CTL_CMD_PING;
                }
        }

        return bytes_read ? (int)bytes_read : err;
}

int evlist__ctlfd_ack(struct evlist *evlist)
{
        int err;

        if (evlist->ctl_fd.ack == -1)
                return 0;

        err = write(evlist->ctl_fd.ack, EVLIST_CTL_CMD_ACK_TAG,
                    sizeof(EVLIST_CTL_CMD_ACK_TAG));
        if (err == -1)
                pr_err("failed to write to ctl_ack_fd %d: %m\n", evlist->ctl_fd.ack);

        return err;
}

static int get_cmd_arg(char *cmd_data, size_t cmd_size, char **arg)
{
        char *data = cmd_data + cmd_size;

        /* no argument */
        if (!*data)
                return 0;

        /* there's argument */
        if (*data == ' ') {
                *arg = data + 1;
                return 1;
        }

        /* malformed */
        return -1;
}

static int evlist__ctlfd_enable(struct evlist *evlist, char *cmd_data, bool enable)
{
        struct evsel *evsel;
        char *name;
        int err;

        err = get_cmd_arg(cmd_data,
                          enable ? sizeof(EVLIST_CTL_CMD_ENABLE_TAG) - 1 :
                                   sizeof(EVLIST_CTL_CMD_DISABLE_TAG) - 1,
                          &name);
        if (err < 0) {
                pr_info("failed: wrong command\n");
                return -1;
        }

        if (err) {
                evsel = evlist__find_evsel_by_str(evlist, name);
                if (evsel) {
                        if (enable)
                                evlist__enable_evsel(evlist, name);
                        else
                                evlist__disable_evsel(evlist, name);
                        pr_info("Event %s %s\n", evsel->name,
                                enable ? "enabled" : "disabled");
                } else {
                        pr_info("failed: can't find '%s' event\n", name);
                }
        } else {
                if (enable) {
                        evlist__enable(evlist);
                        pr_info(EVLIST_ENABLED_MSG);
                } else {
                        evlist__disable(evlist);
                        pr_info(EVLIST_DISABLED_MSG);
                }
        }

        return 0;
}

static int evlist__ctlfd_list(struct evlist *evlist, char *cmd_data)
{
        struct perf_attr_details details = { .verbose = false, };
        struct evsel *evsel;
        char *arg;
        int err;

        err = get_cmd_arg(cmd_data,
                          sizeof(EVLIST_CTL_CMD_EVLIST_TAG) - 1,
                          &arg);
        if (err < 0) {
                pr_info("failed: wrong command\n");
                return -1;
        }

        if (err) {
                if (!strcmp(arg, "-v")) {
                        details.verbose = true;
                } else if (!strcmp(arg, "-g")) {
                        details.event_group = true;
                } else if (!strcmp(arg, "-F")) {
                        details.freq = true;
                } else {
                        pr_info("failed: wrong command\n");
                        return -1;
                }
        }

        evlist__for_each_entry(evlist, evsel)
                evsel__fprintf(evsel, &details, stderr);

        return 0;
}

int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
{
        int err = 0;
        char cmd_data[EVLIST_CTL_CMD_MAX_LEN];
        int ctlfd_pos = evlist->ctl_fd.pos;
        struct pollfd *entries = evlist->core.pollfd.entries;

        if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents)
                return 0;

        if (entries[ctlfd_pos].revents & POLLIN) {
                err = evlist__ctlfd_recv(evlist, cmd, cmd_data,
                                         EVLIST_CTL_CMD_MAX_LEN);
                if (err > 0) {
                        switch (*cmd) {
                        case EVLIST_CTL_CMD_ENABLE:
                        case EVLIST_CTL_CMD_DISABLE:
                                err = evlist__ctlfd_enable(evlist, cmd_data,
                                                           *cmd == EVLIST_CTL_CMD_ENABLE);
                                break;
                        case EVLIST_CTL_CMD_EVLIST:
                                err = evlist__ctlfd_list(evlist, cmd_data);
                                break;
                        case EVLIST_CTL_CMD_SNAPSHOT:
                        case EVLIST_CTL_CMD_STOP:
                        case EVLIST_CTL_CMD_PING:
                                break;
                        case EVLIST_CTL_CMD_ACK:
                        case EVLIST_CTL_CMD_UNSUPPORTED:
                        default:
                                pr_debug("ctlfd: unsupported %d\n", *cmd);
                                break;
                        }
                        if (!(*cmd == EVLIST_CTL_CMD_ACK || *cmd == EVLIST_CTL_CMD_UNSUPPORTED ||
                              *cmd == EVLIST_CTL_CMD_SNAPSHOT))
                                evlist__ctlfd_ack(evlist);
                }
        }

        if (entries[ctlfd_pos].revents & (POLLHUP | POLLERR))
                evlist__finalize_ctlfd(evlist);
        else
                entries[ctlfd_pos].revents = 0;

        return err;
}

/**
 * struct event_enable_time - perf record -D/--delay single time range.
 * @start: start of time range to enable events in milliseconds
 * @end: end of time range to enable events in milliseconds
 *
 * N.B. this structure is also accessed as an array of int.
 */
struct event_enable_time {
        int     start;
        int     end;
};

static int parse_event_enable_time(const char *str, struct event_enable_time *range, bool first)
{
        const char *fmt = first ? "%u - %u %n" : " , %u - %u %n";
        int ret, start, end, n;

        ret = sscanf(str, fmt, &start, &end, &n);
        if (ret != 2 || end <= start)
                return -EINVAL;
        if (range) {
                range->start = start;
                range->end = end;
        }
        return n;
}

static ssize_t parse_event_enable_times(const char *str, struct event_enable_time *range)
{
        int incr = !!range;
        bool first = true;
        ssize_t ret, cnt;

        for (cnt = 0; *str; cnt++) {
                ret = parse_event_enable_time(str, range, first);
                if (ret < 0)
                        return ret;
                /* Check no overlap */
                if (!first && range && range->start <= range[-1].end)
                        return -EINVAL;
                str += ret;
                range += incr;
                first = false;
        }
        return cnt;
}

/**
 * struct event_enable_timer - control structure for perf record -D/--delay.
 * @evlist: event list
 * @times: time ranges that events are enabled (N.B. this is also accessed as an
 *         array of int)
 * @times_cnt: number of time ranges
 * @timerfd: timer file descriptor
 * @pollfd_pos: position in @evlist array of file descriptors to poll (fdarray)
 * @times_step: current position in (int *)@times)[],
 *              refer event_enable_timer__process()
 *
 * Note, this structure is only used when there are time ranges, not when there
 * is only an initial delay.
 */
struct event_enable_timer {
        struct evlist *evlist;
        struct event_enable_time *times;
        size_t  times_cnt;
        int     timerfd;
        int     pollfd_pos;
        size_t  times_step;
};

static int str_to_delay(const char *str)
{
        char *endptr;
        long d;

        d = strtol(str, &endptr, 10);
        if (*endptr || d > INT_MAX || d < -1)
                return 0;
        return d;
}

int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts,
                                    const char *str, int unset)
{
        enum fdarray_flags flags = fdarray_flag__nonfilterable | fdarray_flag__non_perf_event;
        struct event_enable_timer *eet;
        ssize_t times_cnt;
        ssize_t ret;
        int err;

        if (unset)
                return 0;

        opts->target.initial_delay = str_to_delay(str);
        if (opts->target.initial_delay)
                return 0;

        ret = parse_event_enable_times(str, NULL);
        if (ret < 0)
                return ret;

        times_cnt = ret;
        if (times_cnt == 0)
                return -EINVAL;

        eet = zalloc(sizeof(*eet));
        if (!eet)
                return -ENOMEM;

        eet->times = calloc(times_cnt, sizeof(*eet->times));
        if (!eet->times) {
                err = -ENOMEM;
                goto free_eet;
        }

        if (parse_event_enable_times(str, eet->times) != times_cnt) {
                err = -EINVAL;
                goto free_eet_times;
        }

        eet->times_cnt = times_cnt;

        eet->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
        if (eet->timerfd == -1) {
                err = -errno;
                pr_err("timerfd_create failed: %m\n");
                goto free_eet_times;
        }

        eet->pollfd_pos = perf_evlist__add_pollfd(&evlist->core, eet->timerfd, NULL, POLLIN, flags);
        if (eet->pollfd_pos < 0) {
                err = eet->pollfd_pos;
                goto close_timerfd;
        }

        eet->evlist = evlist;
        evlist->eet = eet;
        opts->target.initial_delay = eet->times[0].start;

        return 0;

close_timerfd:
        close(eet->timerfd);
free_eet_times:
        zfree(&eet->times);
free_eet:
        free(eet);
        return err;
}

static int event_enable_timer__set_timer(struct event_enable_timer *eet, int ms)
{
        struct itimerspec its = {
                .it_value.tv_sec = ms / MSEC_PER_SEC,
                .it_value.tv_nsec = (ms % MSEC_PER_SEC) * NSEC_PER_MSEC,
        };
        int err = 0;

        if (timerfd_settime(eet->timerfd, 0, &its, NULL) < 0) {
                err = -errno;
                pr_err("timerfd_settime failed: %m\n");
        }
        return err;
}

int event_enable_timer__start(struct event_enable_timer *eet)
{
        int ms;

        if (!eet)
                return 0;

        ms = eet->times[0].end - eet->times[0].start;
        eet->times_step = 1;

        return event_enable_timer__set_timer(eet, ms);
}

int event_enable_timer__process(struct event_enable_timer *eet)
{
        struct pollfd *entries;
        short revents;

        if (!eet)
                return 0;

        entries = eet->evlist->core.pollfd.entries;
        revents = entries[eet->pollfd_pos].revents;
        entries[eet->pollfd_pos].revents = 0;

        if (revents & POLLIN) {
                size_t step = eet->times_step;
                size_t pos = step / 2;

                if (step & 1) {
                        evlist__disable_non_dummy(eet->evlist);
                        pr_info(EVLIST_DISABLED_MSG);
                        if (pos >= eet->times_cnt - 1) {
                                /* Disarm timer */
                                event_enable_timer__set_timer(eet, 0);
                                return 1; /* Stop */
                        }
                } else {
                        evlist__enable_non_dummy(eet->evlist);
                        pr_info(EVLIST_ENABLED_MSG);
                }

                step += 1;
                pos = step / 2;

                if (pos < eet->times_cnt) {
                        int *times = (int *)eet->times; /* Accessing 'times' as array of int */
                        int ms = times[step] - times[step - 1];

                        eet->times_step = step;
                        return event_enable_timer__set_timer(eet, ms);
                }
        }

        return 0;
}

void event_enable_timer__exit(struct event_enable_timer **ep)
{
        if (!ep || !*ep)
                return;
        zfree(&(*ep)->times);
        zfree(ep);
}

struct evsel *evlist__find_evsel(struct evlist *evlist, int idx)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel->core.idx == idx)
                        return evsel;
        }
        return NULL;
}

void evlist__format_evsels(struct evlist *evlist, struct strbuf *sb, size_t max_length)
{
        struct evsel *evsel, *leader = NULL;
        bool first = true;

        evlist__for_each_entry(evlist, evsel) {
                struct evsel *new_leader = evsel__leader(evsel);

                if (evsel__is_dummy_event(evsel))
                        continue;

                if (leader != new_leader && leader && leader->core.nr_members > 1)
                        strbuf_addch(sb, '}');

                if (!first)
                        strbuf_addch(sb, ',');

                if (sb->len > max_length) {
                        strbuf_addstr(sb, "...");
                        return;
                }
                if (leader != new_leader && new_leader->core.nr_members > 1)
                        strbuf_addch(sb, '{');

                strbuf_addstr(sb, evsel__name(evsel));
                first = false;
                leader = new_leader;
        }
        if (leader && leader->core.nr_members > 1)
                strbuf_addch(sb, '}');
}

void evlist__check_mem_load_aux(struct evlist *evlist)
{
        struct evsel *leader, *evsel, *pos;

        /*
         * For some platforms, the 'mem-loads' event is required to use
         * together with 'mem-loads-aux' within a group and 'mem-loads-aux'
         * must be the group leader. Now we disable this group before reporting
         * because 'mem-loads-aux' is just an auxiliary event. It doesn't carry
         * any valid memory load information.
         */
        evlist__for_each_entry(evlist, evsel) {
                leader = evsel__leader(evsel);
                if (leader == evsel)
                        continue;

                if (leader->name && strstr(leader->name, "mem-loads-aux")) {
                        for_each_group_evsel(pos, leader) {
                                evsel__set_leader(pos, pos);
                                pos->core.nr_members = 0;
                        }
                }
        }
}

/**
 * evlist__warn_user_requested_cpus() - Check each evsel against requested CPUs
 *     and warn if the user CPU list is inapplicable for the event's PMU's
 *     CPUs. Not core PMUs list a CPU in sysfs, but this may be overwritten by a
 *     user requested CPU and so any online CPU is applicable. Core PMUs handle
 *     events on the CPUs in their list and otherwise the event isn't supported.
 * @evlist: The list of events being checked.
 * @cpu_list: The user provided list of CPUs.
 */
void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_list)
{
        struct perf_cpu_map *user_requested_cpus;
        struct evsel *pos;

        if (!cpu_list)
                return;

        user_requested_cpus = perf_cpu_map__new(cpu_list);
        if (!user_requested_cpus)
                return;

        evlist__for_each_entry(evlist, pos) {
                evsel__warn_user_requested_cpus(pos, user_requested_cpus);
        }
        perf_cpu_map__put(user_requested_cpus);
}

/* Should uniquify be disabled for the evlist? */
static bool evlist__disable_uniquify(const struct evlist *evlist)
{
        struct evsel *counter;
        struct perf_pmu *last_pmu = NULL;
        bool first = true;

        evlist__for_each_entry(evlist, counter) {
                /* If PMUs vary then uniquify can be useful. */
                if (!first && counter->pmu != last_pmu)
                        return false;
                first = false;
                if (counter->pmu) {
                        /* Allow uniquify for uncore PMUs. */
                        if (!counter->pmu->is_core)
                                return false;
                        /* Keep hybrid event names uniquified for clarity. */
                        if (perf_pmus__num_core_pmus() > 1)
                                return false;
                }
                last_pmu = counter->pmu;
        }
        return true;
}

static bool evlist__set_needs_uniquify(struct evlist *evlist, const struct perf_stat_config *config)
{
        struct evsel *counter;
        bool needs_uniquify = false;

        if (evlist__disable_uniquify(evlist)) {
                evlist__for_each_entry(evlist, counter)
                        counter->uniquified_name = true;
                return false;
        }

        evlist__for_each_entry(evlist, counter) {
                if (evsel__set_needs_uniquify(counter, config))
                        needs_uniquify = true;
        }
        return needs_uniquify;
}

void evlist__uniquify_evsel_names(struct evlist *evlist, const struct perf_stat_config *config)
{
        if (evlist__set_needs_uniquify(evlist, config)) {
                struct evsel *pos;

                evlist__for_each_entry(evlist, pos)
                        evsel__uniquify_counter(pos);
        }
}

bool evlist__has_bpf_output(struct evlist *evlist)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel__is_bpf_output(evsel))
                        return true;
        }

        return false;
}

bool evlist__needs_bpf_sb_event(struct evlist *evlist)
{
        struct evsel *evsel;

        evlist__for_each_entry(evlist, evsel) {
                if (evsel__is_dummy_event(evsel))
                        continue;
                if (!evsel->core.attr.exclude_kernel)
                        return true;
        }

        return false;
}