hist.c

Go to the documentation of this file.

// SPDX-License-Identifier: GPL-2.0
#include "util.h"
#include "build-id.h"
#include "hist.h"
#include "map.h"
#include "session.h"
#include "namespaces.h"
#include "sort.h"
#include "units.h"
#include "evlist.h"
#include "evsel.h"
#include "annotate.h"
#include "srcline.h"
#include "thread.h"
#include "ui/progress.h"
#include <errno.h>
#include <math.h>
#include <inttypes.h>
#include <sys/param.h>

static bool hists__filter_entry_by_dso(struct hists *hists,
                       struct hist_entry *he);
static bool hists__filter_entry_by_thread(struct hists *hists,
                      struct hist_entry *he);
static bool hists__filter_entry_by_symbol(struct hists *hists,
                      struct hist_entry *he);
static bool hists__filter_entry_by_socket(struct hists *hists,
                      struct hist_entry *he);

u16 hists__col_len(struct hists *hists, enum hist_column col)
{
    return hists->col_len[col];
}

void hists__set_col_len(struct hists *hists, enum hist_column col, u16 len)
{
    hists->col_len[col] = len;
}

bool hists__new_col_len(struct hists *hists, enum hist_column col, u16 len)
{
    if (len > hists__col_len(hists, col)) {
        hists__set_col_len(hists, col, len);
        return true;
    }
    return false;
}

void hists__reset_col_len(struct hists *hists)
{
    enum hist_column col;

    for (col = 0; col < HISTC_NR_COLS; ++col)
        hists__set_col_len(hists, col, 0);
}

static void hists__set_unres_dso_col_len(struct hists *hists, int dso)
{
    const unsigned int unresolved_col_width = BITS_PER_LONG / 4;

    if (hists__col_len(hists, dso) < unresolved_col_width &&
        !symbol_conf.col_width_list_str && !symbol_conf.field_sep &&
        !symbol_conf.dso_list)
        hists__set_col_len(hists, dso, unresolved_col_width);
}

void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
{
    const unsigned int unresolved_col_width = BITS_PER_LONG / 4;
    int symlen;
    u16 len;

    /*
     * +4 accounts for '[x] ' priv level info
     * +2 accounts for 0x prefix on raw addresses
     * +3 accounts for ' y ' symtab origin info
     */
    if (h->ms.sym) {
        symlen = h->ms.sym->namelen + 4;
        if (verbose > 0)
            symlen += BITS_PER_LONG / 4 + 2 + 3;
        hists__new_col_len(hists, HISTC_SYMBOL, symlen);
    } else {
        symlen = unresolved_col_width + 4 + 2;
        hists__new_col_len(hists, HISTC_SYMBOL, symlen);
        hists__set_unres_dso_col_len(hists, HISTC_DSO);
    }

    len = thread__comm_len(h->thread);
    if (hists__new_col_len(hists, HISTC_COMM, len))
        hists__set_col_len(hists, HISTC_THREAD, len + 8);

    if (h->ms.map) {
        len = dso__name_len(h->ms.map->dso);
        hists__new_col_len(hists, HISTC_DSO, len);
    }

    if (h->parent)
        hists__new_col_len(hists, HISTC_PARENT, h->parent->namelen);

    if (h->branch_info) {
        if (h->branch_info->from.sym) {
            symlen = (int)h->branch_info->from.sym->namelen + 4;
            if (verbose > 0)
                symlen += BITS_PER_LONG / 4 + 2 + 3;
            hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);

            symlen = dso__name_len(h->branch_info->from.map->dso);
            hists__new_col_len(hists, HISTC_DSO_FROM, symlen);
        } else {
            symlen = unresolved_col_width + 4 + 2;
            hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);
            hists__set_unres_dso_col_len(hists, HISTC_DSO_FROM);
        }

        if (h->branch_info->to.sym) {
            symlen = (int)h->branch_info->to.sym->namelen + 4;
            if (verbose > 0)
                symlen += BITS_PER_LONG / 4 + 2 + 3;
            hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);

            symlen = dso__name_len(h->branch_info->to.map->dso);
            hists__new_col_len(hists, HISTC_DSO_TO, symlen);
        } else {
            symlen = unresolved_col_width + 4 + 2;
            hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);
            hists__set_unres_dso_col_len(hists, HISTC_DSO_TO);
        }

        if (h->branch_info->srcline_from)
            hists__new_col_len(hists, HISTC_SRCLINE_FROM,
                    strlen(h->branch_info->srcline_from));
        if (h->branch_info->srcline_to)
            hists__new_col_len(hists, HISTC_SRCLINE_TO,
                    strlen(h->branch_info->srcline_to));
    }

    if (h->mem_info) {
        if (h->mem_info->daddr.sym) {
            symlen = (int)h->mem_info->daddr.sym->namelen + 4
                   + unresolved_col_width + 2;
            hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
                       symlen);
            hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
                       symlen + 1);
        } else {
            symlen = unresolved_col_width + 4 + 2;
            hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
                       symlen);
            hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
                       symlen);
        }

        if (h->mem_info->iaddr.sym) {
            symlen = (int)h->mem_info->iaddr.sym->namelen + 4
                   + unresolved_col_width + 2;
            hists__new_col_len(hists, HISTC_MEM_IADDR_SYMBOL,
                       symlen);
        } else {
            symlen = unresolved_col_width + 4 + 2;
            hists__new_col_len(hists, HISTC_MEM_IADDR_SYMBOL,
                       symlen);
        }

        if (h->mem_info->daddr.map) {
            symlen = dso__name_len(h->mem_info->daddr.map->dso);
            hists__new_col_len(hists, HISTC_MEM_DADDR_DSO,
                       symlen);
        } else {
            symlen = unresolved_col_width + 4 + 2;
            hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
        }

        hists__new_col_len(hists, HISTC_MEM_PHYS_DADDR,
                   unresolved_col_width + 4 + 2);

    } else {
        symlen = unresolved_col_width + 4 + 2;
        hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL, symlen);
        hists__new_col_len(hists, HISTC_MEM_IADDR_SYMBOL, symlen);
        hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
    }

    hists__new_col_len(hists, HISTC_CGROUP_ID, 20);
    hists__new_col_len(hists, HISTC_CPU, 3);
    hists__new_col_len(hists, HISTC_SOCKET, 6);
    hists__new_col_len(hists, HISTC_MEM_LOCKED, 6);
    hists__new_col_len(hists, HISTC_MEM_TLB, 22);
    hists__new_col_len(hists, HISTC_MEM_SNOOP, 12);
    hists__new_col_len(hists, HISTC_MEM_LVL, 21 + 3);
    hists__new_col_len(hists, HISTC_LOCAL_WEIGHT, 12);
    hists__new_col_len(hists, HISTC_GLOBAL_WEIGHT, 12);

    if (h->srcline) {
        len = MAX(strlen(h->srcline), strlen(sort_srcline.se_header));
        hists__new_col_len(hists, HISTC_SRCLINE, len);
    }

    if (h->srcfile)
        hists__new_col_len(hists, HISTC_SRCFILE, strlen(h->srcfile));

    if (h->transaction)
        hists__new_col_len(hists, HISTC_TRANSACTION,
                   hist_entry__transaction_len());

    if (h->trace_output)
        hists__new_col_len(hists, HISTC_TRACE, strlen(h->trace_output));
}

void hists__output_recalc_col_len(struct hists *hists, int max_rows)
{
    struct rb_node *next = rb_first(&hists->entries);
    struct hist_entry *n;
    int row = 0;

    hists__reset_col_len(hists);

    while (next && row++ < max_rows) {
        n = rb_entry(next, struct hist_entry, rb_node);
        if (!n->filtered)
            hists__calc_col_len(hists, n);
        next = rb_next(&n->rb_node);
    }
}

static void he_stat__add_cpumode_period(struct he_stat *he_stat,
                    unsigned int cpumode, u64 period)
{
    switch (cpumode) {
    case PERF_RECORD_MISC_KERNEL:
        he_stat->period_sys += period;
        break;
    case PERF_RECORD_MISC_USER:
        he_stat->period_us += period;
        break;
    case PERF_RECORD_MISC_GUEST_KERNEL:
        he_stat->period_guest_sys += period;
        break;
    case PERF_RECORD_MISC_GUEST_USER:
        he_stat->period_guest_us += period;
        break;
    default:
        break;
    }
}

static void he_stat__add_period(struct he_stat *he_stat, u64 period,
                u64 weight)
{

    he_stat->period     += period;
    he_stat->weight     += weight;
    he_stat->nr_events  += 1;
}

static void he_stat__add_stat(struct he_stat *dest, struct he_stat *src)
{
    dest->period        += src->period;
    dest->period_sys    += src->period_sys;
    dest->period_us     += src->period_us;
    dest->period_guest_sys  += src->period_guest_sys;
    dest->period_guest_us   += src->period_guest_us;
    dest->nr_events     += src->nr_events;
    dest->weight        += src->weight;
}

static void he_stat__decay(struct he_stat *he_stat)
{
    he_stat->period = (he_stat->period * 7) / 8;
    he_stat->nr_events = (he_stat->nr_events * 7) / 8;
    /* XXX need decay for weight too? */
}

static void hists__delete_entry(struct hists *hists, struct hist_entry *he);

static bool hists__decay_entry(struct hists *hists, struct hist_entry *he)
{
    u64 prev_period = he->stat.period;
    u64 diff;

    if (prev_period == 0)
        return true;

    he_stat__decay(&he->stat);
    if (symbol_conf.cumulate_callchain)
        he_stat__decay(he->stat_acc);
    decay_callchain(he->callchain);

    diff = prev_period - he->stat.period;

    if (!he->depth) {
        hists->stats.total_period -= diff;
        if (!he->filtered)
            hists->stats.total_non_filtered_period -= diff;
    }

    if (!he->leaf) {
        struct hist_entry *child;
        struct rb_node *node = rb_first(&he->hroot_out);
        while (node) {
            child = rb_entry(node, struct hist_entry, rb_node);
            node = rb_next(node);

            if (hists__decay_entry(hists, child))
                hists__delete_entry(hists, child);
        }
    }

    return he->stat.period == 0;
}

static void hists__delete_entry(struct hists *hists, struct hist_entry *he)
{
    struct rb_root *root_in;
    struct rb_root *root_out;

    if (he->parent_he) {
        root_in  = &he->parent_he->hroot_in;
        root_out = &he->parent_he->hroot_out;
    } else {
        if (hists__has(hists, need_collapse))
            root_in = &hists->entries_collapsed;
        else
            root_in = hists->entries_in;
        root_out = &hists->entries;
    }

    rb_erase(&he->rb_node_in, root_in);
    rb_erase(&he->rb_node, root_out);

    --hists->nr_entries;
    if (!he->filtered)
        --hists->nr_non_filtered_entries;

    hist_entry__delete(he);
}

void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel)
{
    struct rb_node *next = rb_first(&hists->entries);
    struct hist_entry *n;

    while (next) {
        n = rb_entry(next, struct hist_entry, rb_node);
        next = rb_next(&n->rb_node);
        if (((zap_user && n->level == '.') ||
             (zap_kernel && n->level != '.') ||
             hists__decay_entry(hists, n))) {
            hists__delete_entry(hists, n);
        }
    }
}

void hists__delete_entries(struct hists *hists)
{
    struct rb_node *next = rb_first(&hists->entries);
    struct hist_entry *n;

    while (next) {
        n = rb_entry(next, struct hist_entry, rb_node);
        next = rb_next(&n->rb_node);

        hists__delete_entry(hists, n);
    }
}

/*
 * histogram, sorted on item, collects periods
 */

static int hist_entry__init(struct hist_entry *he,
                struct hist_entry *template,
                bool sample_self)
{
    *he = *template;

    if (symbol_conf.cumulate_callchain) {
        he->stat_acc = malloc(sizeof(he->stat));
        if (he->stat_acc == NULL)
            return -ENOMEM;
        memcpy(he->stat_acc, &he->stat, sizeof(he->stat));
        if (!sample_self)
            memset(&he->stat, 0, sizeof(he->stat));
    }

    map__get(he->ms.map);

    if (he->branch_info) {
        /*
         * This branch info is (a part of) allocated from
         * sample__resolve_bstack() and will be freed after
         * adding new entries.  So we need to save a copy.
         */
        he->branch_info = malloc(sizeof(*he->branch_info));
        if (he->branch_info == NULL) {
            map__zput(he->ms.map);
            free(he->stat_acc);
            return -ENOMEM;
        }

        memcpy(he->branch_info, template->branch_info,
               sizeof(*he->branch_info));

        map__get(he->branch_info->from.map);
        map__get(he->branch_info->to.map);
    }

    if (he->mem_info) {
        map__get(he->mem_info->iaddr.map);
        map__get(he->mem_info->daddr.map);
    }

    if (hist_entry__has_callchains(he) && symbol_conf.use_callchain)
        callchain_init(he->callchain);

    if (he->raw_data) {
        he->raw_data = memdup(he->raw_data, he->raw_size);

        if (he->raw_data == NULL) {
            map__put(he->ms.map);
            if (he->branch_info) {
                map__put(he->branch_info->from.map);
                map__put(he->branch_info->to.map);
                free(he->branch_info);
            }
            if (he->mem_info) {
                map__put(he->mem_info->iaddr.map);
                map__put(he->mem_info->daddr.map);
            }
            free(he->stat_acc);
            return -ENOMEM;
        }
    }
    INIT_LIST_HEAD(&he->pairs.node);
    thread__get(he->thread);
    he->hroot_in  = RB_ROOT;
    he->hroot_out = RB_ROOT;

    if (!symbol_conf.report_hierarchy)
        he->leaf = true;

    return 0;
}

static void *hist_entry__zalloc(size_t size)
{
    return zalloc(size + sizeof(struct hist_entry));
}

static void hist_entry__free(void *ptr)
{
    free(ptr);
}

static struct hist_entry_ops default_ops = {
    .new    = hist_entry__zalloc,
    .free   = hist_entry__free,
};

static struct hist_entry *hist_entry__new(struct hist_entry *template,
                      bool sample_self)
{
    struct hist_entry_ops *ops = template->ops;
    size_t callchain_size = 0;
    struct hist_entry *he;
    int err = 0;

    if (!ops)
        ops = template->ops = &default_ops;

    if (symbol_conf.use_callchain)
        callchain_size = sizeof(struct callchain_root);

    he = ops->new(callchain_size);
    if (he) {
        err = hist_entry__init(he, template, sample_self);
        if (err) {
            ops->free(he);
            he = NULL;
        }
    }

    return he;
}

static u8 symbol__parent_filter(const struct symbol *parent)
{
    if (symbol_conf.exclude_other && parent == NULL)
        return 1 << HIST_FILTER__PARENT;
    return 0;
}

static void hist_entry__add_callchain_period(struct hist_entry *he, u64 period)
{
    if (!hist_entry__has_callchains(he) || !symbol_conf.use_callchain)
        return;

    he->hists->callchain_period += period;
    if (!he->filtered)
        he->hists->callchain_non_filtered_period += period;
}

static struct hist_entry *hists__findnew_entry(struct hists *hists,
                           struct hist_entry *entry,
                           struct addr_location *al,
                           bool sample_self)
{
    struct rb_node **p;
    struct rb_node *parent = NULL;
    struct hist_entry *he;
    int64_t cmp;
    u64 period = entry->stat.period;
    u64 weight = entry->stat.weight;

    p = &hists->entries_in->rb_node;

    while (*p != NULL) {
        parent = *p;
        he = rb_entry(parent, struct hist_entry, rb_node_in);

        /*
         * Make sure that it receives arguments in a same order as
         * hist_entry__collapse() so that we can use an appropriate
         * function when searching an entry regardless which sort
         * keys were used.
         */
        cmp = hist_entry__cmp(he, entry);

        if (!cmp) {
            if (sample_self) {
                he_stat__add_period(&he->stat, period, weight);
                hist_entry__add_callchain_period(he, period);
            }
            if (symbol_conf.cumulate_callchain)
                he_stat__add_period(he->stat_acc, period, weight);

            /*
             * This mem info was allocated from sample__resolve_mem
             * and will not be used anymore.
             */
            mem_info__zput(entry->mem_info);

            /* If the map of an existing hist_entry has
             * become out-of-date due to an exec() or
             * similar, update it.  Otherwise we will
             * mis-adjust symbol addresses when computing
             * the history counter to increment.
             */
            if (he->ms.map != entry->ms.map) {
                map__put(he->ms.map);
                he->ms.map = map__get(entry->ms.map);
            }
            goto out;
        }

        if (cmp < 0)
            p = &(*p)->rb_left;
        else
            p = &(*p)->rb_right;
    }

    he = hist_entry__new(entry, sample_self);
    if (!he)
        return NULL;

    if (sample_self)
        hist_entry__add_callchain_period(he, period);
    hists->nr_entries++;

    rb_link_node(&he->rb_node_in, parent, p);
    rb_insert_color(&he->rb_node_in, hists->entries_in);
out:
    if (sample_self)
        he_stat__add_cpumode_period(&he->stat, al->cpumode, period);
    if (symbol_conf.cumulate_callchain)
        he_stat__add_cpumode_period(he->stat_acc, al->cpumode, period);
    return he;
}

static struct hist_entry*
__hists__add_entry(struct hists *hists,
           struct addr_location *al,
           struct symbol *sym_parent,
           struct branch_info *bi,
           struct mem_info *mi,
           struct perf_sample *sample,
           bool sample_self,
           struct hist_entry_ops *ops)
{
    struct namespaces *ns = thread__namespaces(al->thread);
    struct hist_entry entry = {
        .thread = al->thread,
        .comm = thread__comm(al->thread),
        .cgroup_id = {
            .dev = ns ? ns->link_info[CGROUP_NS_INDEX].dev : 0,
            .ino = ns ? ns->link_info[CGROUP_NS_INDEX].ino : 0,
        },
        .ms = {
            .map    = al->map,
            .sym    = al->sym,
        },
        .srcline = al->srcline ? strdup(al->srcline) : NULL,
        .socket  = al->socket,
        .cpu     = al->cpu,
        .cpumode = al->cpumode,
        .ip  = al->addr,
        .level   = al->level,
        .stat = {
            .nr_events = 1,
            .period = sample->period,
            .weight = sample->weight,
        },
        .parent = sym_parent,
        .filtered = symbol__parent_filter(sym_parent) | al->filtered,
        .hists  = hists,
        .branch_info = bi,
        .mem_info = mi,
        .transaction = sample->transaction,
        .raw_data = sample->raw_data,
        .raw_size = sample->raw_size,
        .ops = ops,
    };

    return hists__findnew_entry(hists, &entry, al, sample_self);
}

struct hist_entry *hists__add_entry(struct hists *hists,
                    struct addr_location *al,
                    struct symbol *sym_parent,
                    struct branch_info *bi,
                    struct mem_info *mi,
                    struct perf_sample *sample,
                    bool sample_self)
{
    return __hists__add_entry(hists, al, sym_parent, bi, mi,
                  sample, sample_self, NULL);
}

struct hist_entry *hists__add_entry_ops(struct hists *hists,
                    struct hist_entry_ops *ops,
                    struct addr_location *al,
                    struct symbol *sym_parent,
                    struct branch_info *bi,
                    struct mem_info *mi,
                    struct perf_sample *sample,
                    bool sample_self)
{
    return __hists__add_entry(hists, al, sym_parent, bi, mi,
                  sample, sample_self, ops);
}

static int
iter_next_nop_entry(struct hist_entry_iter *iter __maybe_unused,
            struct addr_location *al __maybe_unused)
{
    return 0;
}

static int
iter_add_next_nop_entry(struct hist_entry_iter *iter __maybe_unused,
            struct addr_location *al __maybe_unused)
{
    return 0;
}

static int
iter_prepare_mem_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    struct perf_sample *sample = iter->sample;
    struct mem_info *mi;

    mi = sample__resolve_mem(sample, al);
    if (mi == NULL)
        return -ENOMEM;

    iter->priv = mi;
    return 0;
}

static int
iter_add_single_mem_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    u64 cost;
    struct mem_info *mi = iter->priv;
    struct hists *hists = evsel__hists(iter->evsel);
    struct perf_sample *sample = iter->sample;
    struct hist_entry *he;

    if (mi == NULL)
        return -EINVAL;

    cost = sample->weight;
    if (!cost)
        cost = 1;

    /*
     * must pass period=weight in order to get the correct
     * sorting from hists__collapse_resort() which is solely
     * based on periods. We want sorting be done on nr_events * weight
     * and this is indirectly achieved by passing period=weight here
     * and the he_stat__add_period() function.
     */
    sample->period = cost;

    he = hists__add_entry(hists, al, iter->parent, NULL, mi,
                  sample, true);
    if (!he)
        return -ENOMEM;

    iter->he = he;
    return 0;
}

static int
iter_finish_mem_entry(struct hist_entry_iter *iter,
              struct addr_location *al __maybe_unused)
{
    struct perf_evsel *evsel = iter->evsel;
    struct hists *hists = evsel__hists(evsel);
    struct hist_entry *he = iter->he;
    int err = -EINVAL;

    if (he == NULL)
        goto out;

    hists__inc_nr_samples(hists, he->filtered);

    err = hist_entry__append_callchain(he, iter->sample);

out:
    /*
     * We don't need to free iter->priv (mem_info) here since the mem info
     * was either already freed in hists__findnew_entry() or passed to a
     * new hist entry by hist_entry__new().
     */
    iter->priv = NULL;

    iter->he = NULL;
    return err;
}

static int
iter_prepare_branch_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    struct branch_info *bi;
    struct perf_sample *sample = iter->sample;

    bi = sample__resolve_bstack(sample, al);
    if (!bi)
        return -ENOMEM;

    iter->curr = 0;
    iter->total = sample->branch_stack->nr;

    iter->priv = bi;
    return 0;
}

static int
iter_add_single_branch_entry(struct hist_entry_iter *iter __maybe_unused,
                 struct addr_location *al __maybe_unused)
{
    return 0;
}

static int
iter_next_branch_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    struct branch_info *bi = iter->priv;
    int i = iter->curr;

    if (bi == NULL)
        return 0;

    if (iter->curr >= iter->total)
        return 0;

    al->map = bi[i].to.map;
    al->sym = bi[i].to.sym;
    al->addr = bi[i].to.addr;
    return 1;
}

static int
iter_add_next_branch_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    struct branch_info *bi;
    struct perf_evsel *evsel = iter->evsel;
    struct hists *hists = evsel__hists(evsel);
    struct perf_sample *sample = iter->sample;
    struct hist_entry *he = NULL;
    int i = iter->curr;
    int err = 0;

    bi = iter->priv;

    if (iter->hide_unresolved && !(bi[i].from.sym && bi[i].to.sym))
        goto out;

    /*
     * The report shows the percentage of total branches captured
     * and not events sampled. Thus we use a pseudo period of 1.
     */
    sample->period = 1;
    sample->weight = bi->flags.cycles ? bi->flags.cycles : 1;

    he = hists__add_entry(hists, al, iter->parent, &bi[i], NULL,
                  sample, true);
    if (he == NULL)
        return -ENOMEM;

    hists__inc_nr_samples(hists, he->filtered);

out:
    iter->he = he;
    iter->curr++;
    return err;
}

static int
iter_finish_branch_entry(struct hist_entry_iter *iter,
             struct addr_location *al __maybe_unused)
{
    zfree(&iter->priv);
    iter->he = NULL;

    return iter->curr >= iter->total ? 0 : -1;
}

static int
iter_prepare_normal_entry(struct hist_entry_iter *iter __maybe_unused,
              struct addr_location *al __maybe_unused)
{
    return 0;
}

static int
iter_add_single_normal_entry(struct hist_entry_iter *iter, struct addr_location *al)
{
    struct perf_evsel *evsel = iter->evsel;
    struct perf_sample *sample = iter->sample;
    struct hist_entry *he;

    he = hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
                  sample, true);
    if (he == NULL)
        return -ENOMEM;

    iter->he = he;
    return 0;
}

static int
iter_finish_normal_entry(struct hist_entry_iter *iter,
             struct addr_location *al __maybe_unused)
{
    struct hist_entry *he = iter->he;
    struct perf_evsel *evsel = iter->evsel;
    struct perf_sample *sample = iter->sample;

    if (he == NULL)
        return 0;

    iter->he = NULL;

    hists__inc_nr_samples(evsel__hists(evsel), he->filtered);

    return hist_entry__append_callchain(he, sample);
}

static int
iter_prepare_cumulative_entry(struct hist_entry_iter *iter,
                  struct addr_location *al __maybe_unused)
{
    struct hist_entry **he_cache;

    callchain_cursor_commit(&callchain_cursor);

    /*
     * This is for detecting cycles or recursions so that they're
     * cumulated only one time to prevent entries more than 100%
     * overhead.
     */
    he_cache = malloc(sizeof(*he_cache) * (callchain_cursor.nr + 1));
    if (he_cache == NULL)
        return -ENOMEM;

    iter->priv = he_cache;
    iter->curr = 0;

    return 0;
}

static int
iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
                 struct addr_location *al)
{
    struct perf_evsel *evsel = iter->evsel;
    struct hists *hists = evsel__hists(evsel);
    struct perf_sample *sample = iter->sample;
    struct hist_entry **he_cache = iter->priv;
    struct hist_entry *he;
    int err = 0;

    he = hists__add_entry(hists, al, iter->parent, NULL, NULL,
                  sample, true);
    if (he == NULL)
        return -ENOMEM;

    iter->he = he;
    he_cache[iter->curr++] = he;

    hist_entry__append_callchain(he, sample);

    /*
     * We need to re-initialize the cursor since callchain_append()
     * advanced the cursor to the end.
     */
    callchain_cursor_commit(&callchain_cursor);

    hists__inc_nr_samples(hists, he->filtered);

    return err;
}

static int
iter_next_cumulative_entry(struct hist_entry_iter *iter,
               struct addr_location *al)
{
    struct callchain_cursor_node *node;

    node = callchain_cursor_current(&callchain_cursor);
    if (node == NULL)
        return 0;

    return fill_callchain_info(al, node, iter->hide_unresolved);
}

static int
iter_add_next_cumulative_entry(struct hist_entry_iter *iter,
                   struct addr_location *al)
{
    struct perf_evsel *evsel = iter->evsel;
    struct perf_sample *sample = iter->sample;
    struct hist_entry **he_cache = iter->priv;
    struct hist_entry *he;
    struct hist_entry he_tmp = {
        .hists = evsel__hists(evsel),
        .cpu = al->cpu,
        .thread = al->thread,
        .comm = thread__comm(al->thread),
        .ip = al->addr,
        .ms = {
            .map = al->map,
            .sym = al->sym,
        },
        .srcline = al->srcline ? strdup(al->srcline) : NULL,
        .parent = iter->parent,
        .raw_data = sample->raw_data,
        .raw_size = sample->raw_size,
    };
    int i;
    struct callchain_cursor cursor;

    callchain_cursor_snapshot(&cursor, &callchain_cursor);

    callchain_cursor_advance(&callchain_cursor);

    /*
     * Check if there's duplicate entries in the callchain.
     * It's possible that it has cycles or recursive calls.
     */
    for (i = 0; i < iter->curr; i++) {
        if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
            /* to avoid calling callback function */
            iter->he = NULL;
            return 0;
        }
    }

    he = hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
                  sample, false);
    if (he == NULL)
        return -ENOMEM;

    iter->he = he;
    he_cache[iter->curr++] = he;

    if (hist_entry__has_callchains(he) && symbol_conf.use_callchain)
        callchain_append(he->callchain, &cursor, sample->period);
    return 0;
}

static int
iter_finish_cumulative_entry(struct hist_entry_iter *iter,
                 struct addr_location *al __maybe_unused)
{
    zfree(&iter->priv);
    iter->he = NULL;

    return 0;
}

const struct hist_iter_ops hist_iter_mem = {
    .prepare_entry      = iter_prepare_mem_entry,
    .add_single_entry   = iter_add_single_mem_entry,
    .next_entry         = iter_next_nop_entry,
    .add_next_entry     = iter_add_next_nop_entry,
    .finish_entry       = iter_finish_mem_entry,
};

const struct hist_iter_ops hist_iter_branch = {
    .prepare_entry      = iter_prepare_branch_entry,
    .add_single_entry   = iter_add_single_branch_entry,
    .next_entry         = iter_next_branch_entry,
    .add_next_entry     = iter_add_next_branch_entry,
    .finish_entry       = iter_finish_branch_entry,
};

const struct hist_iter_ops hist_iter_normal = {
    .prepare_entry      = iter_prepare_normal_entry,
    .add_single_entry   = iter_add_single_normal_entry,
    .next_entry         = iter_next_nop_entry,
    .add_next_entry     = iter_add_next_nop_entry,
    .finish_entry       = iter_finish_normal_entry,
};

const struct hist_iter_ops hist_iter_cumulative = {
    .prepare_entry      = iter_prepare_cumulative_entry,
    .add_single_entry   = iter_add_single_cumulative_entry,
    .next_entry         = iter_next_cumulative_entry,
    .add_next_entry     = iter_add_next_cumulative_entry,
    .finish_entry       = iter_finish_cumulative_entry,
};

int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
             int max_stack_depth, void *arg)
{
    int err, err2;
    struct map *alm = NULL;

    if (al)
        alm = map__get(al->map);

    err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
                    iter->evsel, al, max_stack_depth);
    if (err)
        return err;

    err = iter->ops->prepare_entry(iter, al);
    if (err)
        goto out;

    err = iter->ops->add_single_entry(iter, al);
    if (err)
        goto out;

    if (iter->he && iter->add_entry_cb) {
        err = iter->add_entry_cb(iter, al, true, arg);
        if (err)
            goto out;
    }

    while (iter->ops->next_entry(iter, al)) {
        err = iter->ops->add_next_entry(iter, al);
        if (err)
            break;

        if (iter->he && iter->add_entry_cb) {
            err = iter->add_entry_cb(iter, al, false, arg);
            if (err)
                goto out;
        }
    }

out:
    err2 = iter->ops->finish_entry(iter, al);
    if (!err)
        err = err2;

    map__put(alm);

    return err;
}

int64_t
hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
{
    struct hists *hists = left->hists;
    struct perf_hpp_fmt *fmt;
    int64_t cmp = 0;

    hists__for_each_sort_list(hists, fmt) {
        if (perf_hpp__is_dynamic_entry(fmt) &&
            !perf_hpp__defined_dynamic_entry(fmt, hists))
            continue;

        cmp = fmt->cmp(fmt, left, right);
        if (cmp)
            break;
    }

    return cmp;
}

int64_t
hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
{
    struct hists *hists = left->hists;
    struct perf_hpp_fmt *fmt;
    int64_t cmp = 0;

    hists__for_each_sort_list(hists, fmt) {
        if (perf_hpp__is_dynamic_entry(fmt) &&
            !perf_hpp__defined_dynamic_entry(fmt, hists))
            continue;

        cmp = fmt->collapse(fmt, left, right);
        if (cmp)
            break;
    }

    return cmp;
}

void hist_entry__delete(struct hist_entry *he)
{
    struct hist_entry_ops *ops = he->ops;

    thread__zput(he->thread);
    map__zput(he->ms.map);

    if (he->branch_info) {
        map__zput(he->branch_info->from.map);
        map__zput(he->branch_info->to.map);
        free_srcline(he->branch_info->srcline_from);
        free_srcline(he->branch_info->srcline_to);
        zfree(&he->branch_info);
    }

    if (he->mem_info) {
        map__zput(he->mem_info->iaddr.map);
        map__zput(he->mem_info->daddr.map);
        mem_info__zput(he->mem_info);
    }

    zfree(&he->stat_acc);
    free_srcline(he->srcline);
    if (he->srcfile && he->srcfile[0])
        free(he->srcfile);
    free_callchain(he->callchain);
    free(he->trace_output);
    free(he->raw_data);
    ops->free(he);
}

/*
 * If this is not the last column, then we need to pad it according to the
 * pre-calculated max lenght for this column, otherwise don't bother adding
 * spaces because that would break viewing this with, for instance, 'less',
 * that would show tons of trailing spaces when a long C++ demangled method
 * names is sampled.
*/
int hist_entry__snprintf_alignment(struct hist_entry *he, struct perf_hpp *hpp,
                   struct perf_hpp_fmt *fmt, int printed)
{
    if (!list_is_last(&fmt->list, &he->hists->hpp_list->fields)) {
        const int width = fmt->width(fmt, hpp, he->hists);
        if (printed < width) {
            advance_hpp(hpp, printed);
            printed = scnprintf(hpp->buf, hpp->size, "%-*s", width - printed, " ");
        }
    }

    return printed;
}

/*
 * collapse the histogram
 */

static void hists__apply_filters(struct hists *hists, struct hist_entry *he);
static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *he,
                       enum hist_filter type);

typedef bool (*fmt_chk_fn)(struct perf_hpp_fmt *fmt);

static bool check_thread_entry(struct perf_hpp_fmt *fmt)
{
    return perf_hpp__is_thread_entry(fmt) || perf_hpp__is_comm_entry(fmt);
}

static void hist_entry__check_and_remove_filter(struct hist_entry *he,
                        enum hist_filter type,
                        fmt_chk_fn check)
{
    struct perf_hpp_fmt *fmt;
    bool type_match = false;
    struct hist_entry *parent = he->parent_he;

    switch (type) {
    case HIST_FILTER__THREAD:
        if (symbol_conf.comm_list == NULL &&
            symbol_conf.pid_list == NULL &&
            symbol_conf.tid_list == NULL)
            return;
        break;
    case HIST_FILTER__DSO:
        if (symbol_conf.dso_list == NULL)
            return;
        break;
    case HIST_FILTER__SYMBOL:
        if (symbol_conf.sym_list == NULL)
            return;
        break;
    case HIST_FILTER__PARENT:
    case HIST_FILTER__GUEST:
    case HIST_FILTER__HOST:
    case HIST_FILTER__SOCKET:
    case HIST_FILTER__C2C:
    default:
        return;
    }

    /* if it's filtered by own fmt, it has to have filter bits */
    perf_hpp_list__for_each_format(he->hpp_list, fmt) {
        if (check(fmt)) {
            type_match = true;
            break;
        }
    }

    if (type_match) {
        /*
         * If the filter is for current level entry, propagate
         * filter marker to parents.  The marker bit was
         * already set by default so it only needs to clear
         * non-filtered entries.
         */
        if (!(he->filtered & (1 << type))) {
            while (parent) {
                parent->filtered &= ~(1 << type);
                parent = parent->parent_he;
            }
        }
    } else {
        /*
         * If current entry doesn't have matching formats, set
         * filter marker for upper level entries.  it will be
         * cleared if its lower level entries is not filtered.
         *
         * For lower-level entries, it inherits parent's
         * filter bit so that lower level entries of a
         * non-filtered entry won't set the filter marker.
         */
        if (parent == NULL)
            he->filtered |= (1 << type);
        else
            he->filtered |= (parent->filtered & (1 << type));
    }
}

static void hist_entry__apply_hierarchy_filters(struct hist_entry *he)
{
    hist_entry__check_and_remove_filter(he, HIST_FILTER__THREAD,
                        check_thread_entry);

    hist_entry__check_and_remove_filter(he, HIST_FILTER__DSO,
                        perf_hpp__is_dso_entry);

    hist_entry__check_and_remove_filter(he, HIST_FILTER__SYMBOL,
                        perf_hpp__is_sym_entry);

    hists__apply_filters(he->hists, he);
}

static struct hist_entry *hierarchy_insert_entry(struct hists *hists,
                         struct rb_root *root,
                         struct hist_entry *he,
                         struct hist_entry *parent_he,
                         struct perf_hpp_list *hpp_list)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct hist_entry *iter, *new;
    struct perf_hpp_fmt *fmt;
    int64_t cmp;

    while (*p != NULL) {
        parent = *p;
        iter = rb_entry(parent, struct hist_entry, rb_node_in);

        cmp = 0;
        perf_hpp_list__for_each_sort_list(hpp_list, fmt) {
            cmp = fmt->collapse(fmt, iter, he);
            if (cmp)
                break;
        }

        if (!cmp) {
            he_stat__add_stat(&iter->stat, &he->stat);
            return iter;
        }

        if (cmp < 0)
            p = &parent->rb_left;
        else
            p = &parent->rb_right;
    }

    new = hist_entry__new(he, true);
    if (new == NULL)
        return NULL;

    hists->nr_entries++;

    /* save related format list for output */
    new->hpp_list = hpp_list;
    new->parent_he = parent_he;

    hist_entry__apply_hierarchy_filters(new);

    /* some fields are now passed to 'new' */
    perf_hpp_list__for_each_sort_list(hpp_list, fmt) {
        if (perf_hpp__is_trace_entry(fmt) || perf_hpp__is_dynamic_entry(fmt))
            he->trace_output = NULL;
        else
            new->trace_output = NULL;

        if (perf_hpp__is_srcline_entry(fmt))
            he->srcline = NULL;
        else
            new->srcline = NULL;

        if (perf_hpp__is_srcfile_entry(fmt))
            he->srcfile = NULL;
        else
            new->srcfile = NULL;
    }

    rb_link_node(&new->rb_node_in, parent, p);
    rb_insert_color(&new->rb_node_in, root);
    return new;
}

static int hists__hierarchy_insert_entry(struct hists *hists,
                     struct rb_root *root,
                     struct hist_entry *he)
{
    struct perf_hpp_list_node *node;
    struct hist_entry *new_he = NULL;
    struct hist_entry *parent = NULL;
    int depth = 0;
    int ret = 0;

    list_for_each_entry(node, &hists->hpp_formats, list) {
        /* skip period (overhead) and elided columns */
        if (node->level == 0 || node->skip)
            continue;

        /* insert copy of 'he' for each fmt into the hierarchy */
        new_he = hierarchy_insert_entry(hists, root, he, parent, &node->hpp);
        if (new_he == NULL) {
            ret = -1;
            break;
        }

        root = &new_he->hroot_in;
        new_he->depth = depth++;
        parent = new_he;
    }

    if (new_he) {
        new_he->leaf = true;

        if (hist_entry__has_callchains(new_he) &&
            symbol_conf.use_callchain) {
            callchain_cursor_reset(&callchain_cursor);
            if (callchain_merge(&callchain_cursor,
                        new_he->callchain,
                        he->callchain) < 0)
                ret = -1;
        }
    }

    /* 'he' is no longer used */
    hist_entry__delete(he);

    /* return 0 (or -1) since it already applied filters */
    return ret;
}

static int hists__collapse_insert_entry(struct hists *hists,
                    struct rb_root *root,
                    struct hist_entry *he)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct hist_entry *iter;
    int64_t cmp;

    if (symbol_conf.report_hierarchy)
        return hists__hierarchy_insert_entry(hists, root, he);

    while (*p != NULL) {
        parent = *p;
        iter = rb_entry(parent, struct hist_entry, rb_node_in);

        cmp = hist_entry__collapse(iter, he);

        if (!cmp) {
            int ret = 0;

            he_stat__add_stat(&iter->stat, &he->stat);
            if (symbol_conf.cumulate_callchain)
                he_stat__add_stat(iter->stat_acc, he->stat_acc);

            if (hist_entry__has_callchains(he) && symbol_conf.use_callchain) {
                callchain_cursor_reset(&callchain_cursor);
                if (callchain_merge(&callchain_cursor,
                            iter->callchain,
                            he->callchain) < 0)
                    ret = -1;
            }
            hist_entry__delete(he);
            return ret;
        }

        if (cmp < 0)
            p = &(*p)->rb_left;
        else
            p = &(*p)->rb_right;
    }
    hists->nr_entries++;

    rb_link_node(&he->rb_node_in, parent, p);
    rb_insert_color(&he->rb_node_in, root);
    return 1;
}

struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
{
    struct rb_root *root;

    pthread_mutex_lock(&hists->lock);

    root = hists->entries_in;
    if (++hists->entries_in > &hists->entries_in_array[1])
        hists->entries_in = &hists->entries_in_array[0];

    pthread_mutex_unlock(&hists->lock);

    return root;
}

static void hists__apply_filters(struct hists *hists, struct hist_entry *he)
{
    hists__filter_entry_by_dso(hists, he);
    hists__filter_entry_by_thread(hists, he);
    hists__filter_entry_by_symbol(hists, he);
    hists__filter_entry_by_socket(hists, he);
}

int hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
{
    struct rb_root *root;
    struct rb_node *next;
    struct hist_entry *n;
    int ret;

    if (!hists__has(hists, need_collapse))
        return 0;

    hists->nr_entries = 0;

    root = hists__get_rotate_entries_in(hists);

    next = rb_first(root);

    while (next) {
        if (session_done())
            break;
        n = rb_entry(next, struct hist_entry, rb_node_in);
        next = rb_next(&n->rb_node_in);

        rb_erase(&n->rb_node_in, root);
        ret = hists__collapse_insert_entry(hists, &hists->entries_collapsed, n);
        if (ret < 0)
            return -1;

        if (ret) {
            /*
             * If it wasn't combined with one of the entries already
             * collapsed, we need to apply the filters that may have
             * been set by, say, the hist_browser.
             */
            hists__apply_filters(hists, n);
        }
        if (prog)
            ui_progress__update(prog, 1);
    }
    return 0;
}

static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
{
    struct hists *hists = a->hists;
    struct perf_hpp_fmt *fmt;
    int64_t cmp = 0;

    hists__for_each_sort_list(hists, fmt) {
        if (perf_hpp__should_skip(fmt, a->hists))
            continue;

        cmp = fmt->sort(fmt, a, b);
        if (cmp)
            break;
    }

    return cmp;
}

static void hists__reset_filter_stats(struct hists *hists)
{
    hists->nr_non_filtered_entries = 0;
    hists->stats.total_non_filtered_period = 0;
}

void hists__reset_stats(struct hists *hists)
{
    hists->nr_entries = 0;
    hists->stats.total_period = 0;

    hists__reset_filter_stats(hists);
}

static void hists__inc_filter_stats(struct hists *hists, struct hist_entry *h)
{
    hists->nr_non_filtered_entries++;
    hists->stats.total_non_filtered_period += h->stat.period;
}

void hists__inc_stats(struct hists *hists, struct hist_entry *h)
{
    if (!h->filtered)
        hists__inc_filter_stats(hists, h);

    hists->nr_entries++;
    hists->stats.total_period += h->stat.period;
}

static void hierarchy_recalc_total_periods(struct hists *hists)
{
    struct rb_node *node;
    struct hist_entry *he;

    node = rb_first(&hists->entries);

    hists->stats.total_period = 0;
    hists->stats.total_non_filtered_period = 0;

    /*
     * recalculate total period using top-level entries only
     * since lower level entries only see non-filtered entries
     * but upper level entries have sum of both entries.
     */
    while (node) {
        he = rb_entry(node, struct hist_entry, rb_node);
        node = rb_next(node);

        hists->stats.total_period += he->stat.period;
        if (!he->filtered)
            hists->stats.total_non_filtered_period += he->stat.period;
    }
}

static void hierarchy_insert_output_entry(struct rb_root *root,
                      struct hist_entry *he)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct hist_entry *iter;
    struct perf_hpp_fmt *fmt;

    while (*p != NULL) {
        parent = *p;
        iter = rb_entry(parent, struct hist_entry, rb_node);

        if (hist_entry__sort(he, iter) > 0)
            p = &parent->rb_left;
        else
            p = &parent->rb_right;
    }

    rb_link_node(&he->rb_node, parent, p);
    rb_insert_color(&he->rb_node, root);

    /* update column width of dynamic entry */
    perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
        if (perf_hpp__is_dynamic_entry(fmt))
            fmt->sort(fmt, he, NULL);
    }
}

static void hists__hierarchy_output_resort(struct hists *hists,
                       struct ui_progress *prog,
                       struct rb_root *root_in,
                       struct rb_root *root_out,
                       u64 min_callchain_hits,
                       bool use_callchain)
{
    struct rb_node *node;
    struct hist_entry *he;

    *root_out = RB_ROOT;
    node = rb_first(root_in);

    while (node) {
        he = rb_entry(node, struct hist_entry, rb_node_in);
        node = rb_next(node);

        hierarchy_insert_output_entry(root_out, he);

        if (prog)
            ui_progress__update(prog, 1);

        hists->nr_entries++;
        if (!he->filtered) {
            hists->nr_non_filtered_entries++;
            hists__calc_col_len(hists, he);
        }

        if (!he->leaf) {
            hists__hierarchy_output_resort(hists, prog,
                               &he->hroot_in,
                               &he->hroot_out,
                               min_callchain_hits,
                               use_callchain);
            continue;
        }

        if (!use_callchain)
            continue;

        if (callchain_param.mode == CHAIN_GRAPH_REL) {
            u64 total = he->stat.period;

            if (symbol_conf.cumulate_callchain)
                total = he->stat_acc->period;

            min_callchain_hits = total * (callchain_param.min_percent / 100);
        }

        callchain_param.sort(&he->sorted_chain, he->callchain,
                     min_callchain_hits, &callchain_param);
    }
}

static void __hists__insert_output_entry(struct rb_root *entries,
                     struct hist_entry *he,
                     u64 min_callchain_hits,
                     bool use_callchain)
{
    struct rb_node **p = &entries->rb_node;
    struct rb_node *parent = NULL;
    struct hist_entry *iter;
    struct perf_hpp_fmt *fmt;

    if (use_callchain) {
        if (callchain_param.mode == CHAIN_GRAPH_REL) {
            u64 total = he->stat.period;

            if (symbol_conf.cumulate_callchain)
                total = he->stat_acc->period;

            min_callchain_hits = total * (callchain_param.min_percent / 100);
        }
        callchain_param.sort(&he->sorted_chain, he->callchain,
                      min_callchain_hits, &callchain_param);
    }

    while (*p != NULL) {
        parent = *p;
        iter = rb_entry(parent, struct hist_entry, rb_node);

        if (hist_entry__sort(he, iter) > 0)
            p = &(*p)->rb_left;
        else
            p = &(*p)->rb_right;
    }

    rb_link_node(&he->rb_node, parent, p);
    rb_insert_color(&he->rb_node, entries);

    perf_hpp_list__for_each_sort_list(&perf_hpp_list, fmt) {
        if (perf_hpp__is_dynamic_entry(fmt) &&
            perf_hpp__defined_dynamic_entry(fmt, he->hists))
            fmt->sort(fmt, he, NULL);  /* update column width */
    }
}

static void output_resort(struct hists *hists, struct ui_progress *prog,
              bool use_callchain, hists__resort_cb_t cb)
{
    struct rb_root *root;
    struct rb_node *next;
    struct hist_entry *n;
    u64 callchain_total;
    u64 min_callchain_hits;

    callchain_total = hists->callchain_period;
    if (symbol_conf.filter_relative)
        callchain_total = hists->callchain_non_filtered_period;

    min_callchain_hits = callchain_total * (callchain_param.min_percent / 100);

    hists__reset_stats(hists);
    hists__reset_col_len(hists);

    if (symbol_conf.report_hierarchy) {
        hists__hierarchy_output_resort(hists, prog,
                           &hists->entries_collapsed,
                           &hists->entries,
                           min_callchain_hits,
                           use_callchain);
        hierarchy_recalc_total_periods(hists);
        return;
    }

    if (hists__has(hists, need_collapse))
        root = &hists->entries_collapsed;
    else
        root = hists->entries_in;

    next = rb_first(root);
    hists->entries = RB_ROOT;

    while (next) {
        n = rb_entry(next, struct hist_entry, rb_node_in);
        next = rb_next(&n->rb_node_in);

        if (cb && cb(n))
            continue;

        __hists__insert_output_entry(&hists->entries, n, min_callchain_hits, use_callchain);
        hists__inc_stats(hists, n);

        if (!n->filtered)
            hists__calc_col_len(hists, n);

        if (prog)
            ui_progress__update(prog, 1);
    }
}

void perf_evsel__output_resort(struct perf_evsel *evsel, struct ui_progress *prog)
{
    bool use_callchain;

    if (evsel && symbol_conf.use_callchain && !symbol_conf.show_ref_callgraph)
        use_callchain = evsel__has_callchain(evsel);
    else
        use_callchain = symbol_conf.use_callchain;

    use_callchain |= symbol_conf.show_branchflag_count;

    output_resort(evsel__hists(evsel), prog, use_callchain, NULL);
}

void hists__output_resort(struct hists *hists, struct ui_progress *prog)
{
    output_resort(hists, prog, symbol_conf.use_callchain, NULL);
}

void hists__output_resort_cb(struct hists *hists, struct ui_progress *prog,
                 hists__resort_cb_t cb)
{
    output_resort(hists, prog, symbol_conf.use_callchain, cb);
}

static bool can_goto_child(struct hist_entry *he, enum hierarchy_move_dir hmd)
{
    if (he->leaf || hmd == HMD_FORCE_SIBLING)
        return false;

    if (he->unfolded || hmd == HMD_FORCE_CHILD)
        return true;

    return false;
}

struct rb_node *rb_hierarchy_last(struct rb_node *node)
{
    struct hist_entry *he = rb_entry(node, struct hist_entry, rb_node);

    while (can_goto_child(he, HMD_NORMAL)) {
        node = rb_last(&he->hroot_out);
        he = rb_entry(node, struct hist_entry, rb_node);
    }
    return node;
}

struct rb_node *__rb_hierarchy_next(struct rb_node *node, enum hierarchy_move_dir hmd)
{
    struct hist_entry *he = rb_entry(node, struct hist_entry, rb_node);

    if (can_goto_child(he, hmd))
        node = rb_first(&he->hroot_out);
    else
        node = rb_next(node);

    while (node == NULL) {
        he = he->parent_he;
        if (he == NULL)
            break;

        node = rb_next(&he->rb_node);
    }
    return node;
}

struct rb_node *rb_hierarchy_prev(struct rb_node *node)
{
    struct hist_entry *he = rb_entry(node, struct hist_entry, rb_node);

    node = rb_prev(node);
    if (node)
        return rb_hierarchy_last(node);

    he = he->parent_he;
    if (he == NULL)
        return NULL;

    return &he->rb_node;
}

bool hist_entry__has_hierarchy_children(struct hist_entry *he, float limit)
{
    struct rb_node *node;
    struct hist_entry *child;
    float percent;

    if (he->leaf)
        return false;

    node = rb_first(&he->hroot_out);
    child = rb_entry(node, struct hist_entry, rb_node);

    while (node && child->filtered) {
        node = rb_next(node);
        child = rb_entry(node, struct hist_entry, rb_node);
    }

    if (node)
        percent = hist_entry__get_percent_limit(child);
    else
        percent = 0;

    return node && percent >= limit;
}

static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
                       enum hist_filter filter)
{
    h->filtered &= ~(1 << filter);

    if (symbol_conf.report_hierarchy) {
        struct hist_entry *parent = h->parent_he;

        while (parent) {
            he_stat__add_stat(&parent->stat, &h->stat);

            parent->filtered &= ~(1 << filter);

            if (parent->filtered)
                goto next;

            /* force fold unfiltered entry for simplicity */
            parent->unfolded = false;
            parent->has_no_entry = false;
            parent->row_offset = 0;
            parent->nr_rows = 0;
next:
            parent = parent->parent_he;
        }
    }

    if (h->filtered)
        return;

    /* force fold unfiltered entry for simplicity */
    h->unfolded = false;
    h->has_no_entry = false;
    h->row_offset = 0;
    h->nr_rows = 0;

    hists->stats.nr_non_filtered_samples += h->stat.nr_events;

    hists__inc_filter_stats(hists, h);
    hists__calc_col_len(hists, h);
}


static bool hists__filter_entry_by_dso(struct hists *hists,
                       struct hist_entry *he)
{
    if (hists->dso_filter != NULL &&
        (he->ms.map == NULL || he->ms.map->dso != hists->dso_filter)) {
        he->filtered |= (1 << HIST_FILTER__DSO);
        return true;
    }

    return false;
}

static bool hists__filter_entry_by_thread(struct hists *hists,
                      struct hist_entry *he)
{
    if (hists->thread_filter != NULL &&
        he->thread != hists->thread_filter) {
        he->filtered |= (1 << HIST_FILTER__THREAD);
        return true;
    }

    return false;
}

static bool hists__filter_entry_by_symbol(struct hists *hists,
                      struct hist_entry *he)
{
    if (hists->symbol_filter_str != NULL &&
        (!he->ms.sym || strstr(he->ms.sym->name,
                   hists->symbol_filter_str) == NULL)) {
        he->filtered |= (1 << HIST_FILTER__SYMBOL);
        return true;
    }

    return false;
}

static bool hists__filter_entry_by_socket(struct hists *hists,
                      struct hist_entry *he)
{
    if ((hists->socket_filter > -1) &&
        (he->socket != hists->socket_filter)) {
        he->filtered |= (1 << HIST_FILTER__SOCKET);
        return true;
    }

    return false;
}

typedef bool (*filter_fn_t)(struct hists *hists, struct hist_entry *he);

static void hists__filter_by_type(struct hists *hists, int type, filter_fn_t filter)
{
    struct rb_node *nd;

    hists->stats.nr_non_filtered_samples = 0;

    hists__reset_filter_stats(hists);
    hists__reset_col_len(hists);

    for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
        struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

        if (filter(hists, h))
            continue;

        hists__remove_entry_filter(hists, h, type);
    }
}

static void resort_filtered_entry(struct rb_root *root, struct hist_entry *he)
{
    struct rb_node **p = &root->rb_node;
    struct rb_node *parent = NULL;
    struct hist_entry *iter;
    struct rb_root new_root = RB_ROOT;
    struct rb_node *nd;

    while (*p != NULL) {
        parent = *p;
        iter = rb_entry(parent, struct hist_entry, rb_node);

        if (hist_entry__sort(he, iter) > 0)
            p = &(*p)->rb_left;
        else
            p = &(*p)->rb_right;
    }

    rb_link_node(&he->rb_node, parent, p);
    rb_insert_color(&he->rb_node, root);

    if (he->leaf || he->filtered)
        return;

    nd = rb_first(&he->hroot_out);
    while (nd) {
        struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

        nd = rb_next(nd);
        rb_erase(&h->rb_node, &he->hroot_out);

        resort_filtered_entry(&new_root, h);
    }

    he->hroot_out = new_root;
}

static void hists__filter_hierarchy(struct hists *hists, int type, const void *arg)
{
    struct rb_node *nd;
    struct rb_root new_root = RB_ROOT;

    hists->stats.nr_non_filtered_samples = 0;

    hists__reset_filter_stats(hists);
    hists__reset_col_len(hists);

    nd = rb_first(&hists->entries);
    while (nd) {
        struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
        int ret;

        ret = hist_entry__filter(h, type, arg);

        /*
         * case 1. non-matching type
         * zero out the period, set filter marker and move to child
         */
        if (ret < 0) {
            memset(&h->stat, 0, sizeof(h->stat));
            h->filtered |= (1 << type);

            nd = __rb_hierarchy_next(&h->rb_node, HMD_FORCE_CHILD);
        }
        /*
         * case 2. matched type (filter out)
         * set filter marker and move to next
         */
        else if (ret == 1) {
            h->filtered |= (1 << type);

            nd = __rb_hierarchy_next(&h->rb_node, HMD_FORCE_SIBLING);
        }
        /*
         * case 3. ok (not filtered)
         * add period to hists and parents, erase the filter marker
         * and move to next sibling
         */
        else {
            hists__remove_entry_filter(hists, h, type);

            nd = __rb_hierarchy_next(&h->rb_node, HMD_FORCE_SIBLING);
        }
    }

    hierarchy_recalc_total_periods(hists);

    /*
     * resort output after applying a new filter since filter in a lower
     * hierarchy can change periods in a upper hierarchy.
     */
    nd = rb_first(&hists->entries);
    while (nd) {
        struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

        nd = rb_next(nd);
        rb_erase(&h->rb_node, &hists->entries);

        resort_filtered_entry(&new_root, h);
    }

    hists->entries = new_root;
}

void hists__filter_by_thread(struct hists *hists)
{
    if (symbol_conf.report_hierarchy)
        hists__filter_hierarchy(hists, HIST_FILTER__THREAD,
                    hists->thread_filter);
    else
        hists__filter_by_type(hists, HIST_FILTER__THREAD,
                      hists__filter_entry_by_thread);
}

void hists__filter_by_dso(struct hists *hists)
{
    if (symbol_conf.report_hierarchy)
        hists__filter_hierarchy(hists, HIST_FILTER__DSO,
                    hists->dso_filter);
    else
        hists__filter_by_type(hists, HIST_FILTER__DSO,
                      hists__filter_entry_by_dso);
}

void hists__filter_by_symbol(struct hists *hists)
{
    if (symbol_conf.report_hierarchy)
        hists__filter_hierarchy(hists, HIST_FILTER__SYMBOL,
                    hists->symbol_filter_str);
    else
        hists__filter_by_type(hists, HIST_FILTER__SYMBOL,
                      hists__filter_entry_by_symbol);
}

void hists__filter_by_socket(struct hists *hists)
{
    if (symbol_conf.report_hierarchy)
        hists__filter_hierarchy(hists, HIST_FILTER__SOCKET,
                    &hists->socket_filter);
    else
        hists__filter_by_type(hists, HIST_FILTER__SOCKET,
                      hists__filter_entry_by_socket);
}

void events_stats__inc(struct events_stats *stats, u32 type)
{
    ++stats->nr_events[0];
    ++stats->nr_events[type];
}

void hists__inc_nr_events(struct hists *hists, u32 type)
{
    events_stats__inc(&hists->stats, type);
}

void hists__inc_nr_samples(struct hists *hists, bool filtered)
{
    events_stats__inc(&hists->stats, PERF_RECORD_SAMPLE);
    if (!filtered)
        hists->stats.nr_non_filtered_samples++;
}

static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
                         struct hist_entry *pair)
{
    struct rb_root *root;
    struct rb_node **p;
    struct rb_node *parent = NULL;
    struct hist_entry *he;
    int64_t cmp;

    if (hists__has(hists, need_collapse))
        root = &hists->entries_collapsed;
    else
        root = hists->entries_in;

    p = &root->rb_node;

    while (*p != NULL) {
        parent = *p;
        he = rb_entry(parent, struct hist_entry, rb_node_in);

        cmp = hist_entry__collapse(he, pair);

        if (!cmp)
            goto out;

        if (cmp < 0)
            p = &(*p)->rb_left;
        else
            p = &(*p)->rb_right;
    }

    he = hist_entry__new(pair, true);
    if (he) {
        memset(&he->stat, 0, sizeof(he->stat));
        he->hists = hists;
        if (symbol_conf.cumulate_callchain)
            memset(he->stat_acc, 0, sizeof(he->stat));
        rb_link_node(&he->rb_node_in, parent, p);
        rb_insert_color(&he->rb_node_in, root);
        hists__inc_stats(hists, he);
        he->dummy = true;
    }
out:
    return he;
}

static struct hist_entry *add_dummy_hierarchy_entry(struct hists *hists,
                            struct rb_root *root,
                            struct hist_entry *pair)
{
    struct rb_node **p;
    struct rb_node *parent = NULL;
    struct hist_entry *he;
    struct perf_hpp_fmt *fmt;

    p = &root->rb_node;
    while (*p != NULL) {
        int64_t cmp = 0;

        parent = *p;
        he = rb_entry(parent, struct hist_entry, rb_node_in);

        perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
            cmp = fmt->collapse(fmt, he, pair);
            if (cmp)
                break;
        }
        if (!cmp)
            goto out;

        if (cmp < 0)
            p = &parent->rb_left;
        else
            p = &parent->rb_right;
    }

    he = hist_entry__new(pair, true);
    if (he) {
        rb_link_node(&he->rb_node_in, parent, p);
        rb_insert_color(&he->rb_node_in, root);

        he->dummy = true;
        he->hists = hists;
        memset(&he->stat, 0, sizeof(he->stat));
        hists__inc_stats(hists, he);
    }
out:
    return he;
}

static struct hist_entry *hists__find_entry(struct hists *hists,
                        struct hist_entry *he)
{
    struct rb_node *n;

    if (hists__has(hists, need_collapse))
        n = hists->entries_collapsed.rb_node;
    else
        n = hists->entries_in->rb_node;

    while (n) {
        struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node_in);
        int64_t cmp = hist_entry__collapse(iter, he);

        if (cmp < 0)
            n = n->rb_left;
        else if (cmp > 0)
            n = n->rb_right;
        else
            return iter;
    }

    return NULL;
}

static struct hist_entry *hists__find_hierarchy_entry(struct rb_root *root,
                              struct hist_entry *he)
{
    struct rb_node *n = root->rb_node;

    while (n) {
        struct hist_entry *iter;
        struct perf_hpp_fmt *fmt;
        int64_t cmp = 0;

        iter = rb_entry(n, struct hist_entry, rb_node_in);
        perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
            cmp = fmt->collapse(fmt, iter, he);
            if (cmp)
                break;
        }

        if (cmp < 0)
            n = n->rb_left;
        else if (cmp > 0)
            n = n->rb_right;
        else
            return iter;
    }

    return NULL;
}

static void hists__match_hierarchy(struct rb_root *leader_root,
                   struct rb_root *other_root)
{
    struct rb_node *nd;
    struct hist_entry *pos, *pair;

    for (nd = rb_first(leader_root); nd; nd = rb_next(nd)) {
        pos  = rb_entry(nd, struct hist_entry, rb_node_in);
        pair = hists__find_hierarchy_entry(other_root, pos);

        if (pair) {
            hist_entry__add_pair(pair, pos);
            hists__match_hierarchy(&pos->hroot_in, &pair->hroot_in);
        }
    }
}

/*
 * Look for pairs to link to the leader buckets (hist_entries):
 */
void hists__match(struct hists *leader, struct hists *other)
{
    struct rb_root *root;
    struct rb_node *nd;
    struct hist_entry *pos, *pair;

    if (symbol_conf.report_hierarchy) {
        /* hierarchy report always collapses entries */
        return hists__match_hierarchy(&leader->entries_collapsed,
                          &other->entries_collapsed);
    }

    if (hists__has(leader, need_collapse))
        root = &leader->entries_collapsed;
    else
        root = leader->entries_in;

    for (nd = rb_first(root); nd; nd = rb_next(nd)) {
        pos  = rb_entry(nd, struct hist_entry, rb_node_in);
        pair = hists__find_entry(other, pos);

        if (pair)
            hist_entry__add_pair(pair, pos);
    }
}

static int hists__link_hierarchy(struct hists *leader_hists,
                 struct hist_entry *parent,
                 struct rb_root *leader_root,
                 struct rb_root *other_root)
{
    struct rb_node *nd;
    struct hist_entry *pos, *leader;

    for (nd = rb_first(other_root); nd; nd = rb_next(nd)) {
        pos = rb_entry(nd, struct hist_entry, rb_node_in);

        if (hist_entry__has_pairs(pos)) {
            bool found = false;

            list_for_each_entry(leader, &pos->pairs.head, pairs.node) {
                if (leader->hists == leader_hists) {
                    found = true;
                    break;
                }
            }
            if (!found)
                return -1;
        } else {
            leader = add_dummy_hierarchy_entry(leader_hists,
                               leader_root, pos);
            if (leader == NULL)
                return -1;

            /* do not point parent in the pos */
            leader->parent_he = parent;

            hist_entry__add_pair(pos, leader);
        }

        if (!pos->leaf) {
            if (hists__link_hierarchy(leader_hists, leader,
                          &leader->hroot_in,
                          &pos->hroot_in) < 0)
                return -1;
        }
    }
    return 0;
}

/*
 * Look for entries in the other hists that are not present in the leader, if
 * we find them, just add a dummy entry on the leader hists, with period=0,
 * nr_events=0, to serve as the list header.
 */
int hists__link(struct hists *leader, struct hists *other)
{
    struct rb_root *root;
    struct rb_node *nd;
    struct hist_entry *pos, *pair;

    if (symbol_conf.report_hierarchy) {
        /* hierarchy report always collapses entries */
        return hists__link_hierarchy(leader, NULL,
                         &leader->entries_collapsed,
                         &other->entries_collapsed);
    }

    if (hists__has(other, need_collapse))
        root = &other->entries_collapsed;
    else
        root = other->entries_in;

    for (nd = rb_first(root); nd; nd = rb_next(nd)) {
        pos = rb_entry(nd, struct hist_entry, rb_node_in);

        if (!hist_entry__has_pairs(pos)) {
            pair = hists__add_dummy_entry(leader, pos);
            if (pair == NULL)
                return -1;
            hist_entry__add_pair(pos, pair);
        }
    }

    return 0;
}

void hist__account_cycles(struct branch_stack *bs, struct addr_location *al,
              struct perf_sample *sample, bool nonany_branch_mode)
{
    struct branch_info *bi;

    /* If we have branch cycles always annotate them. */
    if (bs && bs->nr && bs->entries[0].flags.cycles) {
        int i;

        bi = sample__resolve_bstack(sample, al);
        if (bi) {
            struct addr_map_symbol *prev = NULL;

            /*
             * Ignore errors, still want to process the
             * other entries.
             *
             * For non standard branch modes always
             * force no IPC (prev == NULL)
             *
             * Note that perf stores branches reversed from
             * program order!
             */
            for (i = bs->nr - 1; i >= 0; i--) {
                addr_map_symbol__account_cycles(&bi[i].from,
                    nonany_branch_mode ? NULL : prev,
                    bi[i].flags.cycles);
                prev = &bi[i].to;
            }
            free(bi);
        }
    }
}

size_t perf_evlist__fprintf_nr_events(struct perf_evlist *evlist, FILE *fp)
{
    struct perf_evsel *pos;
    size_t ret = 0;

    evlist__for_each_entry(evlist, pos) {
        ret += fprintf(fp, "%s stats:\n", perf_evsel__name(pos));
        ret += events_stats__fprintf(&evsel__hists(pos)->stats, fp);
    }

    return ret;
}


u64 hists__total_period(struct hists *hists)
{
    return symbol_conf.filter_relative ? hists->stats.total_non_filtered_period :
        hists->stats.total_period;
}

int __hists__scnprintf_title(struct hists *hists, char *bf, size_t size, bool show_freq)
{
    char unit;
    int printed;
    const struct dso *dso = hists->dso_filter;
    const struct thread *thread = hists->thread_filter;
    int socket_id = hists->socket_filter;
    unsigned long nr_samples = hists->stats.nr_events[PERF_RECORD_SAMPLE];
    u64 nr_events = hists->stats.total_period;
    struct perf_evsel *evsel = hists_to_evsel(hists);
    const char *ev_name = perf_evsel__name(evsel);
    char buf[512], sample_freq_str[64] = "";
    size_t buflen = sizeof(buf);
    char ref[30] = " show reference callgraph, ";
    bool enable_ref = false;

    if (symbol_conf.filter_relative) {
        nr_samples = hists->stats.nr_non_filtered_samples;
        nr_events = hists->stats.total_non_filtered_period;
    }

    if (perf_evsel__is_group_event(evsel)) {
        struct perf_evsel *pos;

        perf_evsel__group_desc(evsel, buf, buflen);
        ev_name = buf;

        for_each_group_member(pos, evsel) {
            struct hists *pos_hists = evsel__hists(pos);

            if (symbol_conf.filter_relative) {
                nr_samples += pos_hists->stats.nr_non_filtered_samples;
                nr_events += pos_hists->stats.total_non_filtered_period;
            } else {
                nr_samples += pos_hists->stats.nr_events[PERF_RECORD_SAMPLE];
                nr_events += pos_hists->stats.total_period;
            }
        }
    }

    if (symbol_conf.show_ref_callgraph &&
        strstr(ev_name, "call-graph=no"))
        enable_ref = true;

    if (show_freq)
        scnprintf(sample_freq_str, sizeof(sample_freq_str), " %d Hz,", evsel->attr.sample_freq);

    nr_samples = convert_unit(nr_samples, &unit);
    printed = scnprintf(bf, size,
               "Samples: %lu%c of event%s '%s',%s%sEvent count (approx.): %" PRIu64,
               nr_samples, unit, evsel->nr_members > 1 ? "s" : "",
               ev_name, sample_freq_str, enable_ref ? ref : " ", nr_events);


    if (hists->uid_filter_str)
        printed += snprintf(bf + printed, size - printed,
                    ", UID: %s", hists->uid_filter_str);
    if (thread) {
        if (hists__has(hists, thread)) {
            printed += scnprintf(bf + printed, size - printed,
                    ", Thread: %s(%d)",
                     (thread->comm_set ? thread__comm_str(thread) : ""),
                    thread->tid);
        } else {
            printed += scnprintf(bf + printed, size - printed,
                    ", Thread: %s",
                     (thread->comm_set ? thread__comm_str(thread) : ""));
        }
    }
    if (dso)
        printed += scnprintf(bf + printed, size - printed,
                    ", DSO: %s", dso->short_name);
    if (socket_id > -1)
        printed += scnprintf(bf + printed, size - printed,
                    ", Processor Socket: %d", socket_id);

    return printed;
}

int parse_filter_percentage(const struct option *opt __maybe_unused,
                const char *arg, int unset __maybe_unused)
{
    if (!strcmp(arg, "relative"))
        symbol_conf.filter_relative = true;
    else if (!strcmp(arg, "absolute"))
        symbol_conf.filter_relative = false;
    else {
        pr_debug("Invalid percentage: %s\n", arg);
        return -1;
    }

    return 0;
}

int perf_hist_config(const char *var, const char *value)
{
    if (!strcmp(var, "hist.percentage"))
        return parse_filter_percentage(NULL, value, 0);

    return 0;
}

int __hists__init(struct hists *hists, struct perf_hpp_list *hpp_list)
{
    memset(hists, 0, sizeof(*hists));
    hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
    hists->entries_in = &hists->entries_in_array[0];
    hists->entries_collapsed = RB_ROOT;
    hists->entries = RB_ROOT;
    pthread_mutex_init(&hists->lock, NULL);
    hists->socket_filter = -1;
    hists->hpp_list = hpp_list;
    INIT_LIST_HEAD(&hists->hpp_formats);
    return 0;
}

static void hists__delete_remaining_entries(struct rb_root *root)
{
    struct rb_node *node;
    struct hist_entry *he;

    while (!RB_EMPTY_ROOT(root)) {
        node = rb_first(root);
        rb_erase(node, root);

        he = rb_entry(node, struct hist_entry, rb_node_in);
        hist_entry__delete(he);
    }
}

static void hists__delete_all_entries(struct hists *hists)
{
    hists__delete_entries(hists);
    hists__delete_remaining_entries(&hists->entries_in_array[0]);
    hists__delete_remaining_entries(&hists->entries_in_array[1]);
    hists__delete_remaining_entries(&hists->entries_collapsed);
}

static void hists_evsel__exit(struct perf_evsel *evsel)
{
    struct hists *hists = evsel__hists(evsel);
    struct perf_hpp_fmt *fmt, *pos;
    struct perf_hpp_list_node *node, *tmp;

    hists__delete_all_entries(hists);

    list_for_each_entry_safe(node, tmp, &hists->hpp_formats, list) {
        perf_hpp_list__for_each_format_safe(&node->hpp, fmt, pos) {
            list_del(&fmt->list);
            free(fmt);
        }
        list_del(&node->list);
        free(node);
    }
}

static int hists_evsel__init(struct perf_evsel *evsel)
{
    struct hists *hists = evsel__hists(evsel);

    __hists__init(hists, &perf_hpp_list);
    return 0;
}

/*
 * XXX We probably need a hists_evsel__exit() to free the hist_entries
 * stored in the rbtree...
 */

int hists__init(void)
{
    int err = perf_evsel__object_config(sizeof(struct hists_evsel),
                        hists_evsel__init,
                        hists_evsel__exit);
    if (err)
        fputs("FATAL ERROR: Couldn't setup hists class\n", stderr);

    return err;
}

void perf_hpp_list__init(struct perf_hpp_list *list)
{
    INIT_LIST_HEAD(&list->fields);
    INIT_LIST_HEAD(&list->sorts);
}