Initial import

1 files changed, 1482 insertions, 0 deletions

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
new file mode 100644
index 000000000..cc22b9158
--- /dev/null
+++ b/tools/perf/util/hist.c
@@ -0,0 +1,1482 @@
+#include "util.h"
+#include "build-id.h"
+#include "hist.h"
+#include "session.h"
+#include "sort.h"
+#include "evlist.h"
+#include "evsel.h"
+#include "annotate.h"
+#include "ui/progress.h"
+#include <math.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);
+
+u16 hists__col_len(struct hists *hists, enum hist_column col)
+{
+	return hists->col_len[col];
+}
+
+void hists__set_col_len(struct hists *hists, enum hist_column col, u16 len)
+{
+	hists->col_len[col] = len;
+}
+
+bool hists__new_col_len(struct hists *hists, enum hist_column col, u16 len)
+{
+	if (len > hists__col_len(hists, col)) {
+		hists__set_col_len(hists, col, len);
+		return true;
+	}
+	return false;
+}
+
+void hists__reset_col_len(struct hists *hists)
+{
+	enum hist_column col;
+
+	for (col = 0; col < HISTC_NR_COLS; ++col)
+		hists__set_col_len(hists, col, 0);
+}
+
+static void hists__set_unres_dso_col_len(struct hists *hists, int dso)
+{
+	const unsigned int unresolved_col_width = BITS_PER_LONG / 4;
+
+	if (hists__col_len(hists, dso) < unresolved_col_width &&
+	    !symbol_conf.col_width_list_str && !symbol_conf.field_sep &&
+	    !symbol_conf.dso_list)
+		hists__set_col_len(hists, dso, unresolved_col_width);
+}
+
+void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
+{
+	const unsigned int unresolved_col_width = BITS_PER_LONG / 4;
+	int symlen;
+	u16 len;
+
+	/*
+	 * +4 accounts for '[x] ' priv level info
+	 * +2 accounts for 0x prefix on raw addresses
+	 * +3 accounts for ' y ' symtab origin info
+	 */
+	if (h->ms.sym) {
+		symlen = h->ms.sym->namelen + 4;
+		if (verbose)
+			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 + 6);
+
+	if (h->ms.map) {
+		len = dso__name_len(h->ms.map->dso);
+		hists__new_col_len(hists, HISTC_DSO, len);
+	}
+
+	if (h->parent)
+		hists__new_col_len(hists, HISTC_PARENT, h->parent->namelen);
+
+	if (h->branch_info) {
+		if (h->branch_info->from.sym) {
+			symlen = (int)h->branch_info->from.sym->namelen + 4;
+			if (verbose)
+				symlen += BITS_PER_LONG / 4 + 2 + 3;
+			hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);
+
+			symlen = dso__name_len(h->branch_info->from.map->dso);
+			hists__new_col_len(hists, HISTC_DSO_FROM, symlen);
+		} else {
+			symlen = unresolved_col_width + 4 + 2;
+			hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);
+			hists__set_unres_dso_col_len(hists, HISTC_DSO_FROM);
+		}
+
+		if (h->branch_info->to.sym) {
+			symlen = (int)h->branch_info->to.sym->namelen + 4;
+			if (verbose)
+				symlen += BITS_PER_LONG / 4 + 2 + 3;
+			hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);
+
+			symlen = dso__name_len(h->branch_info->to.map->dso);
+			hists__new_col_len(hists, HISTC_DSO_TO, symlen);
+		} else {
+			symlen = unresolved_col_width + 4 + 2;
+			hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);
+			hists__set_unres_dso_col_len(hists, HISTC_DSO_TO);
+		}
+	}
+
+	if (h->mem_info) {
+		if (h->mem_info->daddr.sym) {
+			symlen = (int)h->mem_info->daddr.sym->namelen + 4
+			       + unresolved_col_width + 2;
+			hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
+					   symlen);
+			hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
+					   symlen + 1);
+		} else {
+			symlen = unresolved_col_width + 4 + 2;
+			hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
+					   symlen);
+		}
+		if (h->mem_info->daddr.map) {
+			symlen = dso__name_len(h->mem_info->daddr.map->dso);
+			hists__new_col_len(hists, HISTC_MEM_DADDR_DSO,
+					   symlen);
+		} else {
+			symlen = unresolved_col_width + 4 + 2;
+			hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
+		}
+	} else {
+		symlen = unresolved_col_width + 4 + 2;
+		hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL, symlen);
+		hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
+	}
+
+	hists__new_col_len(hists, HISTC_MEM_LOCKED, 6);
+	hists__new_col_len(hists, HISTC_MEM_TLB, 22);
+	hists__new_col_len(hists, HISTC_MEM_SNOOP, 12);
+	hists__new_col_len(hists, HISTC_MEM_LVL, 21 + 3);
+	hists__new_col_len(hists, HISTC_LOCAL_WEIGHT, 12);
+	hists__new_col_len(hists, HISTC_GLOBAL_WEIGHT, 12);
+
+	if (h->transaction)
+		hists__new_col_len(hists, HISTC_TRANSACTION,
+				   hist_entry__transaction_len());
+}
+
+void hists__output_recalc_col_len(struct hists *hists, int max_rows)
+{
+	struct rb_node *next = rb_first(&hists->entries);
+	struct hist_entry *n;
+	int row = 0;
+
+	hists__reset_col_len(hists);
+
+	while (next && row++ < max_rows) {
+		n = rb_entry(next, struct hist_entry, rb_node);
+		if (!n->filtered)
+			hists__calc_col_len(hists, n);
+		next = rb_next(&n->rb_node);
+	}
+}
+
+static void he_stat__add_cpumode_period(struct he_stat *he_stat,
+					unsigned int cpumode, u64 period)
+{
+	switch (cpumode) {
+	case PERF_RECORD_MISC_KERNEL:
+		he_stat->period_sys += period;
+		break;
+	case PERF_RECORD_MISC_USER:
+		he_stat->period_us += period;
+		break;
+	case PERF_RECORD_MISC_GUEST_KERNEL:
+		he_stat->period_guest_sys += period;
+		break;
+	case PERF_RECORD_MISC_GUEST_USER:
+		he_stat->period_guest_us += period;
+		break;
+	default:
+		break;
+	}
+}
+
+static void he_stat__add_period(struct he_stat *he_stat, u64 period,
+				u64 weight)
+{
+
+	he_stat->period		+= period;
+	he_stat->weight		+= weight;
+	he_stat->nr_events	+= 1;
+}
+
+static void he_stat__add_stat(struct he_stat *dest, struct he_stat *src)
+{
+	dest->period		+= src->period;
+	dest->period_sys	+= src->period_sys;
+	dest->period_us		+= src->period_us;
+	dest->period_guest_sys	+= src->period_guest_sys;
+	dest->period_guest_us	+= src->period_guest_us;
+	dest->nr_events		+= src->nr_events;
+	dest->weight		+= src->weight;
+}
+
+static void he_stat__decay(struct he_stat *he_stat)
+{
+	he_stat->period = (he_stat->period * 7) / 8;
+	he_stat->nr_events = (he_stat->nr_events * 7) / 8;
+	/* XXX need decay for weight too? */
+}
+
+static 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);
+
+	diff = prev_period - he->stat.period;
+
+	hists->stats.total_period -= diff;
+	if (!he->filtered)
+		hists->stats.total_non_filtered_period -= diff;
+
+	return he->stat.period == 0;
+}
+
+static void hists__delete_entry(struct hists *hists, struct hist_entry *he)
+{
+	rb_erase(&he->rb_node, &hists->entries);
+
+	if (sort__need_collapse)
+		rb_erase(&he->rb_node_in, &hists->entries_collapsed);
+
+	--hists->nr_entries;
+	if (!he->filtered)
+		--hists->nr_non_filtered_entries;
+
+	hist_entry__delete(he);
+}
+
+void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel)
+{
+	struct rb_node *next = rb_first(&hists->entries);
+	struct hist_entry *n;
+
+	while (next) {
+		n = rb_entry(next, struct hist_entry, rb_node);
+		next = rb_next(&n->rb_node);
+		if (((zap_user && n->level == '.') ||
+		     (zap_kernel && n->level != '.') ||
+		     hists__decay_entry(hists, n))) {
+			hists__delete_entry(hists, n);
+		}
+	}
+}
+
+void hists__delete_entries(struct hists *hists)
+{
+	struct rb_node *next = rb_first(&hists->entries);
+	struct hist_entry *n;
+
+	while (next) {
+		n = rb_entry(next, struct hist_entry, rb_node);
+		next = rb_next(&n->rb_node);
+
+		hists__delete_entry(hists, n);
+	}
+}
+
+/*
+ * histogram, sorted on item, collects periods
+ */
+
+static struct hist_entry *hist_entry__new(struct hist_entry *template,
+					  bool sample_self)
+{
+	size_t callchain_size = 0;
+	struct hist_entry *he;
+
+	if (symbol_conf.use_callchain)
+		callchain_size = sizeof(struct callchain_root);
+
+	he = zalloc(sizeof(*he) + callchain_size);
+
+	if (he != NULL) {
+		*he = *template;
+
+		if (symbol_conf.cumulate_callchain) {
+			he->stat_acc = malloc(sizeof(he->stat));
+			if (he->stat_acc == NULL) {
+				free(he);
+				return NULL;
+			}
+			memcpy(he->stat_acc, &he->stat, sizeof(he->stat));
+			if (!sample_self)
+				memset(&he->stat, 0, sizeof(he->stat));
+		}
+
+		if (he->ms.map)
+			he->ms.map->referenced = true;
+
+		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) {
+				free(he->stat_acc);
+				free(he);
+				return NULL;
+			}
+
+			memcpy(he->branch_info, template->branch_info,
+			       sizeof(*he->branch_info));
+
+			if (he->branch_info->from.map)
+				he->branch_info->from.map->referenced = true;
+			if (he->branch_info->to.map)
+				he->branch_info->to.map->referenced = true;
+		}
+
+		if (he->mem_info) {
+			if (he->mem_info->iaddr.map)
+				he->mem_info->iaddr.map->referenced = true;
+			if (he->mem_info->daddr.map)
+				he->mem_info->daddr.map->referenced = true;
+		}
+
+		if (symbol_conf.use_callchain)
+			callchain_init(he->callchain);
+
+		INIT_LIST_HEAD(&he->pairs.node);
+		thread__get(he->thread);
+	}
+
+	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 struct hist_entry *add_hist_entry(struct hists *hists,
+					 struct hist_entry *entry,
+					 struct addr_location *al,
+					 bool sample_self)
+{
+	struct rb_node **p;
+	struct rb_node *parent = NULL;
+	struct hist_entry *he;
+	int64_t cmp;
+	u64 period = entry->stat.period;
+	u64 weight = entry->stat.weight;
+
+	p = &hists->entries_in->rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		he = rb_entry(parent, struct hist_entry, rb_node_in);
+
+		/*
+		 * Make sure that it receives arguments in a same order as
+		 * hist_entry__collapse() so that we can use an appropriate
+		 * function when searching an entry regardless which sort
+		 * keys were used.
+		 */
+		cmp = hist_entry__cmp(he, entry);
+
+		if (!cmp) {
+			if (sample_self)
+				he_stat__add_period(&he->stat, period, weight);
+			if (symbol_conf.cumulate_callchain)
+				he_stat__add_period(he->stat_acc, period, weight);
+
+			/*
+			 * This mem info was allocated from sample__resolve_mem
+			 * and will not be used anymore.
+			 */
+			zfree(&entry->mem_info);
+
+			/* If the map of an existing hist_entry has
+			 * become out-of-date due to an exec() or
+			 * similar, update it.  Otherwise we will
+			 * mis-adjust symbol addresses when computing
+			 * the history counter to increment.
+			 */
+			if (he->ms.map != entry->ms.map) {
+				he->ms.map = entry->ms.map;
+				if (he->ms.map)
+					he->ms.map->referenced = true;
+			}
+			goto out;
+		}
+
+		if (cmp < 0)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	he = hist_entry__new(entry, sample_self);
+	if (!he)
+		return NULL;
+
+	hists->nr_entries++;
+
+	rb_link_node(&he->rb_node_in, parent, p);
+	rb_insert_color(&he->rb_node_in, hists->entries_in);
+out:
+	if (sample_self)
+		he_stat__add_cpumode_period(&he->stat, al->cpumode, period);
+	if (symbol_conf.cumulate_callchain)
+		he_stat__add_cpumode_period(he->stat_acc, al->cpumode, period);
+	return he;
+}
+
+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,
+				      u64 period, u64 weight, u64 transaction,
+				      bool sample_self)
+{
+	struct hist_entry entry = {
+		.thread	= al->thread,
+		.comm = thread__comm(al->thread),
+		.ms = {
+			.map	= al->map,
+			.sym	= al->sym,
+		},
+		.cpu	 = al->cpu,
+		.cpumode = al->cpumode,
+		.ip	 = al->addr,
+		.level	 = al->level,
+		.stat = {
+			.nr_events = 1,
+			.period	= period,
+			.weight = weight,
+		},
+		.parent = sym_parent,
+		.filtered = symbol__parent_filter(sym_parent) | al->filtered,
+		.hists	= hists,
+		.branch_info = bi,
+		.mem_info = mi,
+		.transaction = transaction,
+	};
+
+	return add_hist_entry(hists, &entry, al, sample_self);
+}
+
+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 hist_entry *he;
+
+	if (mi == NULL)
+		return -EINVAL;
+
+	cost = iter->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.
+	 */
+	he = __hists__add_entry(hists, al, iter->parent, NULL, mi,
+				cost, cost, 0, true);
+	if (!he)
+		return -ENOMEM;
+
+	iter->he = he;
+	return 0;
+}
+
+static int
+iter_finish_mem_entry(struct hist_entry_iter *iter,
+		      struct addr_location *al __maybe_unused)
+{
+	struct perf_evsel *evsel = iter->evsel;
+	struct hists *hists = evsel__hists(evsel);
+	struct hist_entry *he = iter->he;
+	int err = -EINVAL;
+
+	if (he == NULL)
+		goto out;
+
+	hists__inc_nr_samples(hists, he->filtered);
+
+	err = hist_entry__append_callchain(he, iter->sample);
+
+out:
+	/*
+	 * We don't need to free iter->priv (mem_info) here since
+	 * the mem info was either already freed in add_hist_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)
+{
+	/* to avoid calling callback function */
+	iter->he = NULL;
+
+	return 0;
+}
+
+static int
+iter_next_branch_entry(struct hist_entry_iter *iter, struct addr_location *al)
+{
+	struct branch_info *bi = iter->priv;
+	int i = iter->curr;
+
+	if (bi == NULL)
+		return 0;
+
+	if (iter->curr >= iter->total)
+		return 0;
+
+	al->map = bi[i].to.map;
+	al->sym = bi[i].to.sym;
+	al->addr = bi[i].to.addr;
+	return 1;
+}
+
+static int
+iter_add_next_branch_entry(struct hist_entry_iter *iter, struct addr_location *al)
+{
+	struct branch_info *bi;
+	struct perf_evsel *evsel = iter->evsel;
+	struct hists *hists = evsel__hists(evsel);
+	struct hist_entry *he = NULL;
+	int i = iter->curr;
+	int err = 0;
+
+	bi = iter->priv;
+
+	if (iter->hide_unresolved && !(bi[i].from.sym && bi[i].to.sym))
+		goto out;
+
+	/*
+	 * The report shows the percentage of total branches captured
+	 * and not events sampled. Thus we use a pseudo period of 1.
+	 */
+	he = __hists__add_entry(hists, al, iter->parent, &bi[i], NULL,
+				1, 1, 0, true);
+	if (he == NULL)
+		return -ENOMEM;
+
+	hists__inc_nr_samples(hists, he->filtered);
+
+out:
+	iter->he = he;
+	iter->curr++;
+	return err;
+}
+
+static int
+iter_finish_branch_entry(struct hist_entry_iter *iter,
+			 struct addr_location *al __maybe_unused)
+{
+	zfree(&iter->priv);
+	iter->he = NULL;
+
+	return iter->curr >= iter->total ? 0 : -1;
+}
+
+static int
+iter_prepare_normal_entry(struct hist_entry_iter *iter __maybe_unused,
+			  struct addr_location *al __maybe_unused)
+{
+	return 0;
+}
+
+static int
+iter_add_single_normal_entry(struct hist_entry_iter *iter, struct addr_location *al)
+{
+	struct perf_evsel *evsel = iter->evsel;
+	struct perf_sample *sample = iter->sample;
+	struct hist_entry *he;
+
+	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
+				sample->period, sample->weight,
+				sample->transaction, true);
+	if (he == NULL)
+		return -ENOMEM;
+
+	iter->he = he;
+	return 0;
+}
+
+static int
+iter_finish_normal_entry(struct hist_entry_iter *iter,
+			 struct addr_location *al __maybe_unused)
+{
+	struct hist_entry *he = iter->he;
+	struct perf_evsel *evsel = iter->evsel;
+	struct perf_sample *sample = iter->sample;
+
+	if (he == NULL)
+		return 0;
+
+	iter->he = NULL;
+
+	hists__inc_nr_samples(evsel__hists(evsel), he->filtered);
+
+	return hist_entry__append_callchain(he, sample);
+}
+
+static int
+iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
+			      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) * (PERF_MAX_STACK_DEPTH + 1));
+	if (he_cache == NULL)
+		return -ENOMEM;
+
+	iter->priv = he_cache;
+	iter->curr = 0;
+
+	return 0;
+}
+
+static int
+iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
+				 struct addr_location *al)
+{
+	struct perf_evsel *evsel = iter->evsel;
+	struct hists *hists = evsel__hists(evsel);
+	struct perf_sample *sample = iter->sample;
+	struct hist_entry **he_cache = iter->priv;
+	struct hist_entry *he;
+	int err = 0;
+
+	he = __hists__add_entry(hists, al, iter->parent, NULL, NULL,
+				sample->period, sample->weight,
+				sample->transaction, true);
+	if (he == NULL)
+		return -ENOMEM;
+
+	iter->he = he;
+	he_cache[iter->curr++] = he;
+
+	hist_entry__append_callchain(he, sample);
+
+	/*
+	 * We need to re-initialize the cursor since callchain_append()
+	 * advanced the cursor to the end.
+	 */
+	callchain_cursor_commit(&callchain_cursor);
+
+	hists__inc_nr_samples(hists, he->filtered);
+
+	return err;
+}
+
+static int
+iter_next_cumulative_entry(struct hist_entry_iter *iter,
+			   struct addr_location *al)
+{
+	struct callchain_cursor_node *node;
+
+	node = callchain_cursor_current(&callchain_cursor);
+	if (node == NULL)
+		return 0;
+
+	return fill_callchain_info(al, node, iter->hide_unresolved);
+}
+
+static int
+iter_add_next_cumulative_entry(struct hist_entry_iter *iter,
+			       struct addr_location *al)
+{
+	struct perf_evsel *evsel = iter->evsel;
+	struct perf_sample *sample = iter->sample;
+	struct hist_entry **he_cache = iter->priv;
+	struct hist_entry *he;
+	struct hist_entry he_tmp = {
+		.cpu = al->cpu,
+		.thread = al->thread,
+		.comm = thread__comm(al->thread),
+		.ip = al->addr,
+		.ms = {
+			.map = al->map,
+			.sym = al->sym,
+		},
+		.parent = iter->parent,
+	};
+	int i;
+	struct callchain_cursor cursor;
+
+	callchain_cursor_snapshot(&cursor, &callchain_cursor);
+
+	callchain_cursor_advance(&callchain_cursor);
+
+	/*
+	 * Check if there's duplicate entries in the callchain.
+	 * It's possible that it has cycles or recursive calls.
+	 */
+	for (i = 0; i < iter->curr; i++) {
+		if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
+			/* to avoid calling callback function */
+			iter->he = NULL;
+			return 0;
+		}
+	}
+
+	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
+				sample->period, sample->weight,
+				sample->transaction, false);
+	if (he == NULL)
+		return -ENOMEM;
+
+	iter->he = he;
+	he_cache[iter->curr++] = he;
+
+	if (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,
+			 struct perf_evsel *evsel, struct perf_sample *sample,
+			 int max_stack_depth, void *arg)
+{
+	int err, err2;
+
+	err = sample__resolve_callchain(sample, &iter->parent, evsel, al,
+					max_stack_depth);
+	if (err)
+		return err;
+
+	iter->evsel = evsel;
+	iter->sample = sample;
+
+	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;
+
+	return err;
+}
+
+int64_t
+hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
+{
+	struct perf_hpp_fmt *fmt;
+	int64_t cmp = 0;
+
+	perf_hpp__for_each_sort_list(fmt) {
+		if (perf_hpp__should_skip(fmt))
+			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 perf_hpp_fmt *fmt;
+	int64_t cmp = 0;
+
+	perf_hpp__for_each_sort_list(fmt) {
+		if (perf_hpp__should_skip(fmt))
+			continue;
+
+		cmp = fmt->collapse(fmt, left, right);
+		if (cmp)
+			break;
+	}
+
+	return cmp;
+}
+
+void hist_entry__delete(struct hist_entry *he)
+{
+	thread__zput(he->thread);
+	zfree(&he->branch_info);
+	zfree(&he->mem_info);
+	zfree(&he->stat_acc);
+	free_srcline(he->srcline);
+	free_callchain(he->callchain);
+	free(he);
+}
+
+/*
+ * collapse the histogram
+ */
+
+static bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
+					 struct rb_root *root,
+					 struct hist_entry *he)
+{
+	struct rb_node **p = &root->rb_node;
+	struct rb_node *parent = NULL;
+	struct hist_entry *iter;
+	int64_t cmp;
+
+	while (*p != NULL) {
+		parent = *p;
+		iter = rb_entry(parent, struct hist_entry, rb_node_in);
+
+		cmp = hist_entry__collapse(iter, he);
+
+		if (!cmp) {
+			he_stat__add_stat(&iter->stat, &he->stat);
+			if (symbol_conf.cumulate_callchain)
+				he_stat__add_stat(iter->stat_acc, he->stat_acc);
+
+			if (symbol_conf.use_callchain) {
+				callchain_cursor_reset(&callchain_cursor);
+				callchain_merge(&callchain_cursor,
+						iter->callchain,
+						he->callchain);
+			}
+			hist_entry__delete(he);
+			return false;
+		}
+
+		if (cmp < 0)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+	hists->nr_entries++;
+
+	rb_link_node(&he->rb_node_in, parent, p);
+	rb_insert_color(&he->rb_node_in, root);
+	return true;
+}
+
+static struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
+{
+	struct rb_root *root;
+
+	pthread_mutex_lock(&hists->lock);
+
+	root = hists->entries_in;
+	if (++hists->entries_in > &hists->entries_in_array[1])
+		hists->entries_in = &hists->entries_in_array[0];
+
+	pthread_mutex_unlock(&hists->lock);
+
+	return root;
+}
+
+static void hists__apply_filters(struct hists *hists, struct hist_entry *he)
+{
+	hists__filter_entry_by_dso(hists, he);
+	hists__filter_entry_by_thread(hists, he);
+	hists__filter_entry_by_symbol(hists, he);
+}
+
+void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
+{
+	struct rb_root *root;
+	struct rb_node *next;
+	struct hist_entry *n;
+
+	if (!sort__need_collapse)
+		return;
+
+	hists->nr_entries = 0;
+
+	root = hists__get_rotate_entries_in(hists);
+
+	next = rb_first(root);
+
+	while (next) {
+		if (session_done())
+			break;
+		n = rb_entry(next, struct hist_entry, rb_node_in);
+		next = rb_next(&n->rb_node_in);
+
+		rb_erase(&n->rb_node_in, root);
+		if (hists__collapse_insert_entry(hists, &hists->entries_collapsed, n)) {
+			/*
+			 * 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);
+	}
+}
+
+static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
+{
+	struct perf_hpp_fmt *fmt;
+	int64_t cmp = 0;
+
+	perf_hpp__for_each_sort_list(fmt) {
+		if (perf_hpp__should_skip(fmt))
+			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 __hists__insert_output_entry(struct rb_root *entries,
+					 struct hist_entry *he,
+					 u64 min_callchain_hits)
+{
+	struct rb_node **p = &entries->rb_node;
+	struct rb_node *parent = NULL;
+	struct hist_entry *iter;
+
+	if (symbol_conf.use_callchain)
+		callchain_param.sort(&he->sorted_chain, he->callchain,
+				      min_callchain_hits, &callchain_param);
+
+	while (*p != NULL) {
+		parent = *p;
+		iter = rb_entry(parent, struct hist_entry, rb_node);
+
+		if (hist_entry__sort(he, iter) > 0)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	rb_link_node(&he->rb_node, parent, p);
+	rb_insert_color(&he->rb_node, entries);
+}
+
+void hists__output_resort(struct hists *hists, struct ui_progress *prog)
+{
+	struct rb_root *root;
+	struct rb_node *next;
+	struct hist_entry *n;
+	u64 min_callchain_hits;
+
+	min_callchain_hits = hists->stats.total_period * (callchain_param.min_percent / 100);
+
+	if (sort__need_collapse)
+		root = &hists->entries_collapsed;
+	else
+		root = hists->entries_in;
+
+	next = rb_first(root);
+	hists->entries = RB_ROOT;
+
+	hists__reset_stats(hists);
+	hists__reset_col_len(hists);
+
+	while (next) {
+		n = rb_entry(next, struct hist_entry, rb_node_in);
+		next = rb_next(&n->rb_node_in);
+
+		__hists__insert_output_entry(&hists->entries, n, min_callchain_hits);
+		hists__inc_stats(hists, n);
+
+		if (!n->filtered)
+			hists__calc_col_len(hists, n);
+
+		if (prog)
+			ui_progress__update(prog, 1);
+	}
+}
+
+static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
+				       enum hist_filter filter)
+{
+	h->filtered &= ~(1 << filter);
+	if (h->filtered)
+		return;
+
+	/* force fold unfiltered entry for simplicity */
+	h->ms.unfolded = 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;
+}
+
+void hists__filter_by_dso(struct hists *hists)
+{
+	struct rb_node *nd;
+
+	hists->stats.nr_non_filtered_samples = 0;
+
+	hists__reset_filter_stats(hists);
+	hists__reset_col_len(hists);
+
+	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
+		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+
+		if (symbol_conf.exclude_other && !h->parent)
+			continue;
+
+		if (hists__filter_entry_by_dso(hists, h))
+			continue;
+
+		hists__remove_entry_filter(hists, h, HIST_FILTER__DSO);
+	}
+}
+
+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;
+}
+
+void hists__filter_by_thread(struct hists *hists)
+{
+	struct rb_node *nd;
+
+	hists->stats.nr_non_filtered_samples = 0;
+
+	hists__reset_filter_stats(hists);
+	hists__reset_col_len(hists);
+
+	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
+		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+
+		if (hists__filter_entry_by_thread(hists, h))
+			continue;
+
+		hists__remove_entry_filter(hists, h, HIST_FILTER__THREAD);
+	}
+}
+
+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;
+}
+
+void hists__filter_by_symbol(struct hists *hists)
+{
+	struct rb_node *nd;
+
+	hists->stats.nr_non_filtered_samples = 0;
+
+	hists__reset_filter_stats(hists);
+	hists__reset_col_len(hists);
+
+	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
+		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+
+		if (hists__filter_entry_by_symbol(hists, h))
+			continue;
+
+		hists__remove_entry_filter(hists, h, HIST_FILTER__SYMBOL);
+	}
+}
+
+void events_stats__inc(struct events_stats *stats, u32 type)
+{
+	++stats->nr_events[0];
+	++stats->nr_events[type];
+}
+
+void hists__inc_nr_events(struct hists *hists, u32 type)
+{
+	events_stats__inc(&hists->stats, type);
+}
+
+void hists__inc_nr_samples(struct hists *hists, bool filtered)
+{
+	events_stats__inc(&hists->stats, PERF_RECORD_SAMPLE);
+	if (!filtered)
+		hists->stats.nr_non_filtered_samples++;
+}
+
+static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
+						 struct hist_entry *pair)
+{
+	struct rb_root *root;
+	struct rb_node **p;
+	struct rb_node *parent = NULL;
+	struct hist_entry *he;
+	int64_t cmp;
+
+	if (sort__need_collapse)
+		root = &hists->entries_collapsed;
+	else
+		root = hists->entries_in;
+
+	p = &root->rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		he = rb_entry(parent, struct hist_entry, rb_node_in);
+
+		cmp = hist_entry__collapse(he, pair);
+
+		if (!cmp)
+			goto out;
+
+		if (cmp < 0)
+			p = &(*p)->rb_left;
+		else
+			p = &(*p)->rb_right;
+	}
+
+	he = hist_entry__new(pair, true);
+	if (he) {
+		memset(&he->stat, 0, sizeof(he->stat));
+		he->hists = hists;
+		rb_link_node(&he->rb_node_in, parent, p);
+		rb_insert_color(&he->rb_node_in, root);
+		hists__inc_stats(hists, he);
+		he->dummy = true;
+	}
+out:
+	return he;
+}
+
+static struct hist_entry *hists__find_entry(struct hists *hists,
+					    struct hist_entry *he)
+{
+	struct rb_node *n;
+
+	if (sort__need_collapse)
+		n = hists->entries_collapsed.rb_node;
+	else
+		n = hists->entries_in->rb_node;
+
+	while (n) {
+		struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node_in);
+		int64_t cmp = hist_entry__collapse(iter, he);
+
+		if (cmp < 0)
+			n = n->rb_left;
+		else if (cmp > 0)
+			n = n->rb_right;
+		else
+			return iter;
+	}
+
+	return NULL;
+}
+
+/*
+ * Look for pairs to link to the leader buckets (hist_entries):
+ */
+void hists__match(struct hists *leader, struct hists *other)
+{
+	struct rb_root *root;
+	struct rb_node *nd;
+	struct hist_entry *pos, *pair;
+
+	if (sort__need_collapse)
+		root = &leader->entries_collapsed;
+	else
+		root = leader->entries_in;
+
+	for (nd = rb_first(root); nd; nd = rb_next(nd)) {
+		pos  = rb_entry(nd, struct hist_entry, rb_node_in);
+		pair = hists__find_entry(other, pos);
+
+		if (pair)
+			hist_entry__add_pair(pair, pos);
+	}
+}
+
+/*
+ * Look for entries in the other hists that are not present in the leader, if
+ * we find them, just add a dummy entry on the leader hists, with period=0,
+ * nr_events=0, to serve as the list header.
+ */
+int hists__link(struct hists *leader, struct hists *other)
+{
+	struct rb_root *root;
+	struct rb_node *nd;
+	struct hist_entry *pos, *pair;
+
+	if (sort__need_collapse)
+		root = &other->entries_collapsed;
+	else
+		root = other->entries_in;
+
+	for (nd = rb_first(root); nd; nd = rb_next(nd)) {
+		pos = rb_entry(nd, struct hist_entry, rb_node_in);
+
+		if (!hist_entry__has_pairs(pos)) {
+			pair = hists__add_dummy_entry(leader, pos);
+			if (pair == NULL)
+				return -1;
+			hist_entry__add_pair(pos, pair);
+		}
+	}
+
+	return 0;
+}
+
+
+size_t perf_evlist__fprintf_nr_events(struct perf_evlist *evlist, FILE *fp)
+{
+	struct perf_evsel *pos;
+	size_t ret = 0;
+
+	evlist__for_each(evlist, pos) {
+		ret += fprintf(fp, "%s stats:\n", perf_evsel__name(pos));
+		ret += events_stats__fprintf(&evsel__hists(pos)->stats, fp);
+	}
+
+	return ret;
+}
+
+
+u64 hists__total_period(struct hists *hists)
+{
+	return symbol_conf.filter_relative ? hists->stats.total_non_filtered_period :
+		hists->stats.total_period;
+}
+
+int 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
+		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;
+}
+
+static int hists_evsel__init(struct perf_evsel *evsel)
+{
+	struct hists *hists = evsel__hists(evsel);
+
+	memset(hists, 0, sizeof(*hists));
+	hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
+	hists->entries_in = &hists->entries_in_array[0];
+	hists->entries_collapsed = RB_ROOT;
+	hists->entries = RB_ROOT;
+	pthread_mutex_init(&hists->lock, NULL);
+	return 0;
+}
+
+/*
+ * XXX We probably need a hists_evsel__exit() to free the hist_entries
+ * stored in the rbtree...
+ */
+
+int hists__init(void)
+{
+	int err = perf_evsel__object_config(sizeof(struct hists_evsel),
+					    hists_evsel__init, NULL);
+	if (err)
+		fputs("FATAL ERROR: Couldn't setup hists class\n", stderr);
+
+	return err;
+}