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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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__new_col_len(hists, HISTC_ADDR_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__new_col_len(hists, HISTC_ADDR_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_LOCAL_P_STAGE_CYC, 13);
     hists__new_col_len(hists, HISTC_GLOBAL_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)
 {
     he_stat->period     += period;
     he_stat->nr_events  += 1;
 }
 
 static void he_stat__add_stat(struct he_stat *dest, struct he_stat *src)
 {
     dest->period        += src->period;
     dest->period_sys    += src->period_sys;
     dest->period_us     += src->period_us;
     dest->period_guest_sys  += src->period_guest_sys;
     dest->period_guest_us   += src->period_guest_us;
     dest->nr_events     += src->nr_events;
 }
 
 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;
     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);
                 hist_entry__add_callchain_period(he, period);
             }
             if (symbol_conf.cumulate_callchain)
                 he_stat__add_period(he->stat_acc, period);
 
             /*
              * 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,
         },
         .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),
         .weight = sample->weight,
         .ins_lat = sample->ins_lat,
         .p_stage_cyc = sample->p_stage_cyc,
     }, *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);
 }