// SPDX-License-Identifier: GPL-2.0
#include "callchain.h"
#include "debug.h"
#include "dso.h"
#include "build-id.h"
#include "hist.h"
#include "map.h"
#include "map_symbol.h"
#include "branch.h"
#include "mem-events.h"
#include "session.h"
#include "namespaces.h"
#include "cgroup.h"
#include "sort.h"
#include "units.h"
#include "evlist.h"
#include "evsel.h"
#include "annotate.h"
#include "srcline.h"
#include "symbol.h"
#include "thread.h"
#include "block-info.h"
#include "ui/progress.h"
#include <errno.h>
#include <math.h>
#include <inttypes.h>
#include <sys/param.h>
#include <linux/rbtree.h>
#include <linux/string.h>
#include <linux/time64.h>
#include <linux/zalloc.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;

        if (h->block_info)
                return;
        /*
         * +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.ms.sym) {
                        symlen = (int)h->branch_info->from.ms.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.ms.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.ms.sym) {
                        symlen = (int)h->branch_info->to.ms.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.ms.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.ms.sym) {
                        symlen = (int)h->mem_info->daddr.ms.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.ms.sym) {
                        symlen = (int)h->mem_info->iaddr.ms.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.ms.map) {
                        symlen = dso__name_len(h->mem_info->daddr.ms.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);

                hists__new_col_len(hists, HISTC_MEM_DATA_PAGE_SIZE,
                                   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, 6);
        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);
        hists__new_col_len(hists, HISTC_MEM_BLOCKED, 10);
        hists__new_col_len(hists, HISTC_LOCAL_INS_LAT, 13);
        hists__new_col_len(hists, HISTC_GLOBAL_INS_LAT, 13);
        hists__new_col_len(hists, HISTC_P_STAGE_CYC, 13);
        if (symbol_conf.nanosecs)
                hists__new_col_len(hists, HISTC_TIME, 16);
        else
                hists__new_col_len(hists, HISTC_TIME, 12);
        hists__new_col_len(hists, HISTC_CODE_PAGE_SIZE, 6);

        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));

        if (h->cgroup) {
                const char *cgrp_name = "unknown";
                struct cgroup *cgrp = cgroup__find(h->ms.maps->machine->env,
                                                   h->cgroup);
                if (cgrp != NULL)
                        cgrp_name = cgrp->name;

                hists__new_col_len(hists, HISTC_CGROUP, strlen(cgrp_name));
        }
}

void hists__output_recalc_col_len(struct hists *hists, int max_rows)
{
        struct rb_node *next = rb_first_cached(&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 long hist_time(unsigned long htime)
{
        unsigned long time_quantum = symbol_conf.time_quantum;
        if (time_quantum)
                return (htime / time_quantum) * time_quantum;
        return htime;
}

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

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

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;
        dest->ins_lat           += src->ins_lat;
        dest->p_stage_cyc               += src->p_stage_cyc;
}

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_cached(&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_cached *root_in;
        struct rb_root_cached *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_cached(&he->rb_node_in, root_in);
        rb_erase_cached(&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_cached(&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_cached(&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);
        }
}

struct hist_entry *hists__get_entry(struct hists *hists, int idx)
{
        struct rb_node *next = rb_first_cached(&hists->entries);
        struct hist_entry *n;
        int i = 0;

        while (next) {
                n = rb_entry(next, struct hist_entry, rb_node);
                if (i == idx)
                        return n;

                next = rb_next(&n->rb_node);
                i++;
        }

        return NULL;
}

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

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

        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)
                        goto err;

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

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

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

        if (he->srcline) {
                he->srcline = strdup(he->srcline);
                if (he->srcline == NULL)
                        goto err_rawdata;
        }

        if (symbol_conf.res_sample) {
                he->res_samples = calloc(sizeof(struct res_sample),
                                        symbol_conf.res_sample);
                if (!he->res_samples)
                        goto err_srcline;
        }

        INIT_LIST_HEAD(&he->pairs.node);
        thread__get(he->thread);
        he->hroot_in  = RB_ROOT_CACHED;
        he->hroot_out = RB_ROOT_CACHED;

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

        return 0;

err_srcline:
        zfree(&he->srcline);

err_rawdata:
        zfree(&he->raw_data);

err_infos:
        if (he->branch_info) {
                map__put(he->branch_info->from.ms.map);
                map__put(he->branch_info->to.ms.map);
                zfree(&he->branch_info);
        }
        if (he->mem_info) {
                map__put(he->mem_info->iaddr.ms.map);
                map__put(he->mem_info->daddr.ms.map);
        }
err:
        map__zput(he->ms.map);
        zfree(&he->stat_acc);
        return -ENOMEM;
}

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, callchain_size);
                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;
        u64 ins_lat = entry->stat.ins_lat;
        u64 p_stage_cyc = entry->stat.p_stage_cyc;
        bool leftmost = true;

        p = &hists->entries_in->rb_root.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, ins_lat, p_stage_cyc);
                                hist_entry__add_callchain_period(he, period);
                        }
                        if (symbol_conf.cumulate_callchain)
                                he_stat__add_period(he->stat_acc, period, weight, ins_lat, p_stage_cyc);

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

                        block_info__zput(entry->block_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;
                        leftmost = false;
                }
        }

        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_cached(&he->rb_node_in, hists->entries_in, leftmost);
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 unsigned random_max(unsigned high)
{
        unsigned thresh = -high % high;
        for (;;) {
                unsigned r = random();
                if (r >= thresh)
                        return r % high;
        }
}

static void hists__res_sample(struct hist_entry *he, struct perf_sample *sample)
{
        struct res_sample *r;
        int j;

        if (he->num_res < symbol_conf.res_sample) {
                j = he->num_res++;
        } else {
                j = random_max(symbol_conf.res_sample);
        }
        r = &he->res_samples[j];
        r->time = sample->time;
        r->cpu = sample->cpu;
        r->tid = sample->tid;
}

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 block_info *block_info,
                   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,
                },
                .cgroup = sample->cgroup,
                .ms = {
                        .maps   = al->maps,
                        .map    = al->map,
                        .sym    = al->sym,
                },
                .srcline = (char *) al->srcline,
                .socket  = al->socket,
                .cpu     = al->cpu,
                .cpumode = al->cpumode,
                .ip      = al->addr,
                .level   = al->level,
                .code_page_size = sample->code_page_size,
                .stat = {
                        .nr_events = 1,
                        .period = sample->period,
                        .weight = sample->weight,
                        .ins_lat = sample->ins_lat,
                        .p_stage_cyc = sample->p_stage_cyc,
                },
                .parent = sym_parent,
                .filtered = symbol__parent_filter(sym_parent) | al->filtered,
                .hists  = hists,
                .branch_info = bi,
                .mem_info = mi,
                .block_info = block_info,
                .transaction = sample->transaction,
                .raw_data = sample->raw_data,
                .raw_size = sample->raw_size,
                .ops = ops,
                .time = hist_time(sample->time),
        }, *he = hists__findnew_entry(hists, &entry, al, sample_self);

        if (!hists->has_callchains && he && he->callchain_size != 0)
                hists->has_callchains = true;
        if (he && symbol_conf.res_sample)
                hists__res_sample(he, sample);
        return he;
}

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, NULL,
                                  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, NULL,
                                  sample, sample_self, ops);
}

struct hist_entry *hists__add_entry_block(struct hists *hists,
                                          struct addr_location *al,
                                          struct block_info *block_info)
{
        struct hist_entry entry = {
                .block_info = block_info,
                .hists = hists,
                .ms = {
                        .maps = al->maps,
                        .map = al->map,
                        .sym = al->sym,
                },
        }, *he = hists__findnew_entry(hists, &entry, al, false);

        return he;
}

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 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->maps = bi[i].to.ms.maps;
        al->map = bi[i].to.ms.map;
        al->sym = bi[i].to.ms.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 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.ms.sym && bi[i].to.ms.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 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 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 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 bool
hist_entry__fast__sym_diff(struct hist_entry *left,
                           struct hist_entry *right)
{
        struct symbol *sym_l = left->ms.sym;
        struct symbol *sym_r = right->ms.sym;

        if (!sym_l && !sym_r)
                return left->ip != right->ip;

        return !!_sort__sym_cmp(sym_l, sym_r);
}


static int
iter_add_next_cumulative_entry(struct hist_entry_iter *iter,
                               struct addr_location *al)
{
        struct 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 = {
                        .maps = al->maps,
                        .map = al->map,
                        .sym = al->sym,
                },
                .srcline = (char *) al->srcline,
                .parent = iter->parent,
                .raw_data = sample->raw_data,
                .raw_size = sample->raw_size,
        };
        int i;
        struct callchain_cursor cursor;
        bool fast = hists__has(he_tmp.hists, sym);

        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++) {
                /*
                 * For most cases, there are no duplicate entries in callchain.
                 * The symbols are usually different. Do a quick check for
                 * symbols first.
                 */
                if (fast && hist_entry__fast__sym_diff(he_cache[i], &he_tmp))
                        continue;

                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) {
                map__put(alm);
                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.ms.map);
                map__zput(he->branch_info->to.ms.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.ms.map);
                map__zput(he->mem_info->daddr.ms.map);
                mem_info__zput(he->mem_info);
        }

        if (he->block_info)
                block_info__zput(he->block_info);

        zfree(&he->res_samples);
        zfree(&he->stat_acc);
        free_srcline(he->srcline);
        if (he->srcfile && he->srcfile[0])
                zfree(&he->srcfile);
        free_callchain(he->callchain);
        zfree(&he->trace_output);
        zfree(&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 length 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_cached *root,
                                                 struct hist_entry *he,
                                                 struct hist_entry *parent_he,
                                                 struct perf_hpp_list *hpp_list)
{
        struct rb_node **p = &root->rb_root.rb_node;
        struct rb_node *parent = NULL;
        struct hist_entry *iter, *new;
        struct perf_hpp_fmt *fmt;
        int64_t cmp;
        bool leftmost = true;

        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;
                        leftmost = false;
                }
        }

        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_cached(&new->rb_node_in, root, leftmost);
        return new;
}

static int hists__hierarchy_insert_entry(struct hists *hists,
                                         struct rb_root_cached *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_cached *root,
                                        struct hist_entry *he)
{
        struct rb_node **p = &root->rb_root.rb_node;
        struct rb_node *parent = NULL;
        struct hist_entry *iter;
        int64_t cmp;
        bool leftmost = true;

        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;
                        leftmost = false;
                }
        }
        hists->nr_entries++;

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

struct rb_root_cached *hists__get_rotate_entries_in(struct hists *hists)
{
        struct rb_root_cached *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_cached *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_cached(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_cached(&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 int64_t 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_cached(&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_cached *root,
                                          struct hist_entry *he)
{
        struct rb_node **p = &root->rb_root.rb_node;
        struct rb_node *parent = NULL;
        struct hist_entry *iter;
        struct perf_hpp_fmt *fmt;
        bool leftmost = true;

        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;
                        leftmost = false;
                }
        }

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

        /* 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_cached *root_in,
                                           struct rb_root_cached *root_out,
                                           u64 min_callchain_hits,
                                           bool use_callchain)
{
        struct rb_node *node;
        struct hist_entry *he;

        *root_out = RB_ROOT_CACHED;
        node = rb_first_cached(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_cached *entries,
                                         struct hist_entry *he,
                                         u64 min_callchain_hits,
                                         bool use_callchain)
{
        struct rb_node **p = &entries->rb_root.rb_node;
        struct rb_node *parent = NULL;
        struct hist_entry *iter;
        struct perf_hpp_fmt *fmt;
        bool leftmost = true;

        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;
                        leftmost = false;
                }
        }

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

        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,
                          void *cb_arg)
{
        struct rb_root_cached *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_cached(root);
        hists->entries = RB_ROOT_CACHED;

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

                if (cb && cb(n, cb_arg))
                        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 evsel__output_resort_cb(struct evsel *evsel, struct ui_progress *prog,
                             hists__resort_cb_t cb, void *cb_arg)
{
        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, cb, cb_arg);
}

void evsel__output_resort(struct evsel *evsel, struct ui_progress *prog)
{
        return evsel__output_resort_cb(evsel, prog, NULL, NULL);
}

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

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.rb_root);
                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_cached(&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_cached(&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_cached(&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_cached *root,
                                  struct hist_entry *he)
{
        struct rb_node **p = &root->rb_root.rb_node;
        struct rb_node *parent = NULL;
        struct hist_entry *iter;
        struct rb_root_cached new_root = RB_ROOT_CACHED;
        struct rb_node *nd;
        bool leftmost = true;

        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;
                        leftmost = false;
                }
        }

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

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

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

                nd = rb_next(nd);
                rb_erase_cached(&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_cached new_root = RB_ROOT_CACHED;

        hists->stats.nr_non_filtered_samples = 0;

        hists__reset_filter_stats(hists);
        hists__reset_col_len(hists);

        nd = rb_first_cached(&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_cached(&hists->entries);
        while (nd) {
                struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

                nd = rb_next(nd);
                rb_erase_cached(&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];
}

static void hists_stats__inc(struct hists_stats *stats)
{
        ++stats->nr_samples;
}

void hists__inc_nr_events(struct hists *hists)
{
        hists_stats__inc(&hists->stats);
}

void hists__inc_nr_samples(struct hists *hists, bool filtered)
{
        hists_stats__inc(&hists->stats);
        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_cached *root;
        struct rb_node **p;
        struct rb_node *parent = NULL;
        struct hist_entry *he;
        int64_t cmp;
        bool leftmost = true;

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

        p = &root->rb_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;
                        leftmost = false;
                }
        }

        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_cached(&he->rb_node_in, root, leftmost);
                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_cached *root,
                                                    struct hist_entry *pair)
{
        struct rb_node **p;
        struct rb_node *parent = NULL;
        struct hist_entry *he;
        struct perf_hpp_fmt *fmt;
        bool leftmost = true;

        p = &root->rb_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;
                        leftmost = false;
                }
        }

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

                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_root.rb_node;
        else
                n = hists->entries_in->rb_root.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_cached *root,
                                                      struct hist_entry *he)
{
        struct rb_node *n = root->rb_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_cached *leader_root,
                                   struct rb_root_cached *other_root)
{
        struct rb_node *nd;
        struct hist_entry *pos, *pair;

        for (nd = rb_first_cached(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_cached *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_cached(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_cached *leader_root,
                                 struct rb_root_cached *other_root)
{
        struct rb_node *nd;
        struct hist_entry *pos, *leader;

        for (nd = rb_first_cached(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_cached *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_cached(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;
}

int hists__unlink(struct hists *hists)
{
        struct rb_root_cached *root;
        struct rb_node *nd;
        struct hist_entry *pos;

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

        for (nd = rb_first_cached(root); nd; nd = rb_next(nd)) {
                pos = rb_entry(nd, struct hist_entry, rb_node_in);
                list_del_init(&pos->pairs.node);
        }

        return 0;
}

void hist__account_cycles(struct branch_stack *bs, struct addr_location *al,
                          struct perf_sample *sample, bool nonany_branch_mode,
                          u64 *total_cycles)
{
        struct branch_info *bi;
        struct branch_entry *entries = perf_sample__branch_entries(sample);

        /* If we have branch cycles always annotate them. */
        if (bs && bs->nr && 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;

                                if (total_cycles)
                                        *total_cycles += bi[i].flags.cycles;
                        }
                        free(bi);
                }
        }
}

size_t evlist__fprintf_nr_events(struct evlist *evlist, FILE *fp,
                                 bool skip_empty)
{
        struct evsel *pos;
        size_t ret = 0;

        evlist__for_each_entry(evlist, pos) {
                struct hists *hists = evsel__hists(pos);

                if (skip_empty && !hists->stats.nr_samples)
                        continue;

                ret += fprintf(fp, "%s stats:\n", evsel__name(pos));
                ret += fprintf(fp, "%16s events: %10d\n",
                               "SAMPLE", hists->stats.nr_samples);
        }

        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;
        struct thread *thread = hists->thread_filter;
        int socket_id = hists->socket_filter;
        unsigned long nr_samples = hists->stats.nr_samples;
        u64 nr_events = hists->stats.total_period;
        struct evsel *evsel = hists_to_evsel(hists);
        const char *ev_name = 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 (evsel__is_group_event(evsel)) {
                struct evsel *pos;

                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_samples;
                                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->core.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->core.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_CACHED;
        hists->entries_in = &hists->entries_in_array[0];
        hists->entries_collapsed = RB_ROOT_CACHED;
        hists->entries = RB_ROOT_CACHED;
        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_cached *root)
{
        struct rb_node *node;
        struct hist_entry *he;

        while (!RB_EMPTY_ROOT(&root->rb_root)) {
                node = rb_first_cached(root);
                rb_erase_cached(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 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_init(&fmt->list);
                        free(fmt);
                }
                list_del_init(&node->list);
                free(node);
        }
}

static int hists_evsel__init(struct 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 = 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);
}