hist.c 33.9 KB
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#include "util.h"
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#include "build-id.h"
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#include "hist.h"
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#include "session.h"
#include "sort.h"
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#include "evlist.h"
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#include "evsel.h"
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#include "annotate.h"
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#include "ui/progress.h"
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#include <math.h>
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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);
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static bool hists__filter_entry_by_symbol(struct hists *hists,
					  struct hist_entry *he);
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u16 hists__col_len(struct hists *hists, enum hist_column col)
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{
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	return hists->col_len[col];
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}

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

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

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

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

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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);
}

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

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	/*
	 * +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 {
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		symlen = unresolved_col_width + 4 + 2;
		hists__new_col_len(hists, HISTC_SYMBOL, symlen);
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		hists__set_unres_dso_col_len(hists, HISTC_DSO);
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	}
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	len = thread__comm_len(h->thread);
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	if (hists__new_col_len(hists, HISTC_COMM, len))
		hists__set_col_len(hists, HISTC_THREAD, len + 6);
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	if (h->ms.map) {
		len = dso__name_len(h->ms.map->dso);
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		hists__new_col_len(hists, HISTC_DSO, len);
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	}
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	if (h->parent)
		hists__new_col_len(hists, HISTC_PARENT, h->parent->namelen);

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	if (h->branch_info) {
		if (h->branch_info->from.sym) {
			symlen = (int)h->branch_info->from.sym->namelen + 4;
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			if (verbose)
				symlen += BITS_PER_LONG / 4 + 2 + 3;
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			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;
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			if (verbose)
				symlen += BITS_PER_LONG / 4 + 2 + 3;
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			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);
		}
	}
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	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);
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			hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
					   symlen + 1);
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		} 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);
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	if (h->transaction)
		hists__new_col_len(hists, HISTC_TRANSACTION,
				   hist_entry__transaction_len());
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}

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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);
	}
}

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

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static void he_stat__add_period(struct he_stat *he_stat, u64 period,
				u64 weight)
198
{
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200
	he_stat->period		+= period;
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	he_stat->weight		+= weight;
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	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;
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	dest->weight		+= src->weight;
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}

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

static bool hists__decay_entry(struct hists *hists, struct hist_entry *he)
{
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	u64 prev_period = he->stat.period;
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	u64 diff;
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	if (prev_period == 0)
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		return true;
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	he_stat__decay(&he->stat);
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	if (symbol_conf.cumulate_callchain)
		he_stat__decay(he->stat_acc);
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	diff = prev_period - he->stat.period;

	hists->stats.total_period -= diff;
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	if (!he->filtered)
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		hists->stats.total_non_filtered_period -= diff;
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	return he->stat.period == 0;
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}

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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);
}

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void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel)
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{
	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);
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		/*
		 * We may be annotating this, for instance, so keep it here in
		 * case some it gets new samples, we'll eventually free it when
		 * the user stops browsing and it agains gets fully decayed.
		 */
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		if (((zap_user && n->level == '.') ||
		     (zap_kernel && n->level != '.') ||
		     hists__decay_entry(hists, n)) &&
		    !n->used) {
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			hists__delete_entry(hists, n);
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		}
	}
}

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Namhyung Kim 已提交
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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);

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		hists__delete_entry(hists, n);
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Namhyung Kim 已提交
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	}
}

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

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static struct hist_entry *hist_entry__new(struct hist_entry *template,
					  bool sample_self)
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{
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	size_t callchain_size = 0;
	struct hist_entry *he;

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

	he = zalloc(sizeof(*he) + callchain_size);
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	if (he != NULL) {
		*he = *template;
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		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));
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			if (!sample_self)
				memset(&he->stat, 0, sizeof(he->stat));
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		}

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

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

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			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;
		}

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		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;
		}

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		if (symbol_conf.use_callchain)
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			callchain_init(he->callchain);
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		INIT_LIST_HEAD(&he->pairs.node);
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	}

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	return he;
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}

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

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static struct hist_entry *add_hist_entry(struct hists *hists,
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					 struct hist_entry *entry,
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					 struct addr_location *al,
					 bool sample_self)
374
{
375
	struct rb_node **p;
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	struct rb_node *parent = NULL;
	struct hist_entry *he;
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	int64_t cmp;
379 380
	u64 period = entry->stat.period;
	u64 weight = entry->stat.weight;
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	p = &hists->entries_in->rb_node;

384 385
	while (*p != NULL) {
		parent = *p;
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		he = rb_entry(parent, struct hist_entry, rb_node_in);
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		/*
		 * 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);
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		if (!cmp) {
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			if (sample_self)
				he_stat__add_period(&he->stat, period, weight);
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			if (symbol_conf.cumulate_callchain)
				he_stat__add_period(he->stat_acc, period, weight);
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402
			/*
403
			 * This mem info was allocated from sample__resolve_mem
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			 * and will not be used anymore.
			 */
406
			zfree(&entry->mem_info);
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			/* 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;
			}
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			goto out;
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		}

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

428
	he = hist_entry__new(entry, sample_self);
429
	if (!he)
430
		return NULL;
431

432 433
	hists->nr_entries++;

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	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, hists->entries_in);
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out:
437 438
	if (sample_self)
		he_stat__add_cpumode_period(&he->stat, al->cpumode, period);
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	if (symbol_conf.cumulate_callchain)
		he_stat__add_cpumode_period(he->stat_acc, al->cpumode, period);
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	return he;
}

444
struct hist_entry *__hists__add_entry(struct hists *hists,
445
				      struct addr_location *al,
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				      struct symbol *sym_parent,
				      struct branch_info *bi,
				      struct mem_info *mi,
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				      u64 period, u64 weight, u64 transaction,
				      bool sample_self)
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{
	struct hist_entry entry = {
		.thread	= al->thread,
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		.comm = thread__comm(al->thread),
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		.ms = {
			.map	= al->map,
			.sym	= al->sym,
		},
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		.cpu	 = al->cpu,
		.cpumode = al->cpumode,
		.ip	 = al->addr,
		.level	 = al->level,
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		.stat = {
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			.nr_events = 1,
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			.period	= period,
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			.weight = weight,
467
		},
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		.parent = sym_parent,
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		.filtered = symbol__parent_filter(sym_parent) | al->filtered,
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		.hists	= hists,
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		.branch_info = bi,
		.mem_info = mi,
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		.transaction = transaction,
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	};

476
	return add_hist_entry(hists, &entry, al, sample_self);
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}

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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;
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	struct hists *hists = evsel__hists(iter->evsel);
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	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.
	 */
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	he = __hists__add_entry(hists, al, iter->parent, NULL, mi,
530
				cost, cost, 0, true);
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	if (!he)
		return -ENOMEM;

	iter->he = he;
	return 0;
}

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

	if (he == NULL)
		goto out;

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	hists__inc_nr_samples(hists, he->filtered);
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	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)
{
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	/* to avoid calling callback function */
	iter->he = NULL;

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	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)
{
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	struct branch_info *bi;
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	struct perf_evsel *evsel = iter->evsel;
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	struct hists *hists = evsel__hists(evsel);
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	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.
	 */
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	he = __hists__add_entry(hists, al, iter->parent, &bi[i], NULL,
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				1, 1, 0, true);
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	if (he == NULL)
		return -ENOMEM;

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	hists__inc_nr_samples(hists, he->filtered);
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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;

667
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
668
				sample->period, sample->weight,
669
				sample->transaction, true);
670 671 672 673 674 675 676 677
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
	return 0;
}

static int
678 679
iter_finish_normal_entry(struct hist_entry_iter *iter,
			 struct addr_location *al __maybe_unused)
680 681 682 683 684 685 686 687 688 689
{
	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;

690
	hists__inc_nr_samples(evsel__hists(evsel), he->filtered);
691 692 693 694

	return hist_entry__append_callchain(he, sample);
}

695 696 697 698
static int
iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
			      struct addr_location *al __maybe_unused)
{
699 700
	struct hist_entry **he_cache;

701
	callchain_cursor_commit(&callchain_cursor);
702 703 704 705 706 707 708 709 710 711 712 713 714

	/*
	 * 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;

715 716 717 718 719 720 721 722
	return 0;
}

static int
iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
				 struct addr_location *al)
{
	struct perf_evsel *evsel = iter->evsel;
723
	struct hists *hists = evsel__hists(evsel);
724
	struct perf_sample *sample = iter->sample;
725
	struct hist_entry **he_cache = iter->priv;
726 727 728
	struct hist_entry *he;
	int err = 0;

729
	he = __hists__add_entry(hists, al, iter->parent, NULL, NULL,
730 731 732 733 734 735
				sample->period, sample->weight,
				sample->transaction, true);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
736
	he_cache[iter->curr++] = he;
737

738
	hist_entry__append_callchain(he, sample);
739 740 741 742 743 744 745

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

746
	hists__inc_nr_samples(hists, he->filtered);
747 748 749 750 751 752 753 754 755 756 757 758 759 760

	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;

761
	return fill_callchain_info(al, node, iter->hide_unresolved);
762 763 764 765 766 767 768 769
}

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;
770
	struct hist_entry **he_cache = iter->priv;
771
	struct hist_entry *he;
772 773 774 775 776 777 778 779 780 781 782 783
	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;
784 785 786 787 788
	struct callchain_cursor cursor;

	callchain_cursor_snapshot(&cursor, &callchain_cursor);

	callchain_cursor_advance(&callchain_cursor);
789 790 791 792 793 794

	/*
	 * 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++) {
795 796 797
		if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
			/* to avoid calling callback function */
			iter->he = NULL;
798
			return 0;
799
		}
800
	}
801

802
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
803 804 805 806 807 808
				sample->period, sample->weight,
				sample->transaction, false);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
809
	he_cache[iter->curr++] = he;
810

811 812
	if (symbol_conf.use_callchain)
		callchain_append(he->callchain, &cursor, sample->period);
813 814 815 816 817 818 819
	return 0;
}

static int
iter_finish_cumulative_entry(struct hist_entry_iter *iter,
			     struct addr_location *al __maybe_unused)
{
820
	zfree(&iter->priv);
821
	iter->he = NULL;
822

823 824 825
	return 0;
}

826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849
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,
};

850 851 852 853 854 855 856 857
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,
};

858 859
int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
			 struct perf_evsel *evsel, struct perf_sample *sample,
860
			 int max_stack_depth, void *arg)
861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
{
	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;

880 881 882 883 884 885
	if (iter->he && iter->add_entry_cb) {
		err = iter->add_entry_cb(iter, al, true, arg);
		if (err)
			goto out;
	}

886 887 888 889
	while (iter->ops->next_entry(iter, al)) {
		err = iter->ops->add_next_entry(iter, al);
		if (err)
			break;
890 891 892 893 894 895

		if (iter->he && iter->add_entry_cb) {
			err = iter->add_entry_cb(iter, al, false, arg);
			if (err)
				goto out;
		}
896 897 898 899 900 901 902 903 904 905
	}

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

	return err;
}

906 907 908
int64_t
hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
{
909
	struct perf_hpp_fmt *fmt;
910 911
	int64_t cmp = 0;

912
	perf_hpp__for_each_sort_list(fmt) {
913 914 915
		if (perf_hpp__should_skip(fmt))
			continue;

916
		cmp = fmt->cmp(fmt, left, right);
917 918 919 920 921 922 923 924 925 926
		if (cmp)
			break;
	}

	return cmp;
}

int64_t
hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
{
927
	struct perf_hpp_fmt *fmt;
928 929
	int64_t cmp = 0;

930
	perf_hpp__for_each_sort_list(fmt) {
931 932 933
		if (perf_hpp__should_skip(fmt))
			continue;

934
		cmp = fmt->collapse(fmt, left, right);
935 936 937 938 939 940 941
		if (cmp)
			break;
	}

	return cmp;
}

942
void hist_entry__delete(struct hist_entry *he)
943
{
944 945
	zfree(&he->branch_info);
	zfree(&he->mem_info);
946
	zfree(&he->stat_acc);
947
	free_srcline(he->srcline);
948
	free_callchain(he->callchain);
949 950 951 952 953 954 955
	free(he);
}

/*
 * collapse the histogram
 */

956
static bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
957 958
					 struct rb_root *root,
					 struct hist_entry *he)
959
{
960
	struct rb_node **p = &root->rb_node;
961 962 963 964 965 966
	struct rb_node *parent = NULL;
	struct hist_entry *iter;
	int64_t cmp;

	while (*p != NULL) {
		parent = *p;
967
		iter = rb_entry(parent, struct hist_entry, rb_node_in);
968 969 970 971

		cmp = hist_entry__collapse(iter, he);

		if (!cmp) {
972
			he_stat__add_stat(&iter->stat, &he->stat);
973 974
			if (symbol_conf.cumulate_callchain)
				he_stat__add_stat(iter->stat_acc, he->stat_acc);
975

976
			if (symbol_conf.use_callchain) {
977 978 979
				callchain_cursor_reset(&callchain_cursor);
				callchain_merge(&callchain_cursor,
						iter->callchain,
980 981
						he->callchain);
			}
982
			hist_entry__delete(he);
983
			return false;
984 985 986 987 988 989 990
		}

		if (cmp < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
991
	hists->nr_entries++;
992

993 994
	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, root);
995
	return true;
996 997
}

998
static struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
999
{
1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012
	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;
}

1013 1014 1015 1016
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);
1017
	hists__filter_entry_by_symbol(hists, he);
1018 1019
}

1020
void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
1021 1022
{
	struct rb_root *root;
1023 1024 1025
	struct rb_node *next;
	struct hist_entry *n;

1026
	if (!sort__need_collapse)
1027 1028
		return;

1029 1030
	hists->nr_entries = 0;

1031
	root = hists__get_rotate_entries_in(hists);
1032

1033
	next = rb_first(root);
1034

1035
	while (next) {
1036 1037
		if (session_done())
			break;
1038 1039
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1040

1041
		rb_erase(&n->rb_node_in, root);
1042 1043 1044 1045 1046 1047 1048 1049
		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);
		}
1050 1051
		if (prog)
			ui_progress__update(prog, 1);
1052
	}
1053
}
1054

1055
static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
1056
{
1057 1058
	struct perf_hpp_fmt *fmt;
	int64_t cmp = 0;
1059

1060
	perf_hpp__for_each_sort_list(fmt) {
1061 1062 1063
		if (perf_hpp__should_skip(fmt))
			continue;

1064
		cmp = fmt->sort(fmt, a, b);
1065
		if (cmp)
1066 1067 1068
			break;
	}

1069
	return cmp;
1070 1071
}

1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100
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;
}

1101 1102 1103
static void __hists__insert_output_entry(struct rb_root *entries,
					 struct hist_entry *he,
					 u64 min_callchain_hits)
1104
{
1105
	struct rb_node **p = &entries->rb_node;
1106 1107 1108
	struct rb_node *parent = NULL;
	struct hist_entry *iter;

1109
	if (symbol_conf.use_callchain)
1110
		callchain_param.sort(&he->sorted_chain, he->callchain,
1111 1112 1113 1114 1115 1116
				      min_callchain_hits, &callchain_param);

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

1117
		if (hist_entry__sort(he, iter) > 0)
1118 1119 1120 1121 1122 1123
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}

	rb_link_node(&he->rb_node, parent, p);
1124
	rb_insert_color(&he->rb_node, entries);
1125 1126
}

1127
void hists__output_resort(struct hists *hists, struct ui_progress *prog)
1128
{
1129
	struct rb_root *root;
1130 1131 1132 1133
	struct rb_node *next;
	struct hist_entry *n;
	u64 min_callchain_hits;

1134
	min_callchain_hits = hists->stats.total_period * (callchain_param.min_percent / 100);
1135

1136
	if (sort__need_collapse)
1137 1138 1139 1140 1141 1142
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	next = rb_first(root);
	hists->entries = RB_ROOT;
1143

1144
	hists__reset_stats(hists);
1145
	hists__reset_col_len(hists);
1146

1147
	while (next) {
1148 1149
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1150

1151
		__hists__insert_output_entry(&hists->entries, n, min_callchain_hits);
1152
		hists__inc_stats(hists, n);
1153 1154 1155

		if (!n->filtered)
			hists__calc_col_len(hists, n);
1156 1157 1158

		if (prog)
			ui_progress__update(prog, 1);
1159
	}
1160
}
1161

1162
static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
1163 1164 1165 1166 1167 1168
				       enum hist_filter filter)
{
	h->filtered &= ~(1 << filter);
	if (h->filtered)
		return;

1169 1170
	/* force fold unfiltered entry for simplicity */
	h->ms.unfolded = false;
1171
	h->row_offset = 0;
1172

1173
	hists->stats.nr_non_filtered_samples += h->stat.nr_events;
1174

1175
	hists__inc_filter_stats(hists, h);
1176
	hists__calc_col_len(hists, h);
1177 1178
}

1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191

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;
}

1192
void hists__filter_by_dso(struct hists *hists)
1193 1194 1195
{
	struct rb_node *nd;

1196
	hists->stats.nr_non_filtered_samples = 0;
1197 1198

	hists__reset_filter_stats(hists);
1199
	hists__reset_col_len(hists);
1200

1201
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1202 1203 1204 1205 1206
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

		if (symbol_conf.exclude_other && !h->parent)
			continue;

1207
		if (hists__filter_entry_by_dso(hists, h))
1208 1209
			continue;

1210
		hists__remove_entry_filter(hists, h, HIST_FILTER__DSO);
1211 1212 1213
	}
}

1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
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;
}

1226
void hists__filter_by_thread(struct hists *hists)
1227 1228 1229
{
	struct rb_node *nd;

1230
	hists->stats.nr_non_filtered_samples = 0;
1231 1232

	hists__reset_filter_stats(hists);
1233
	hists__reset_col_len(hists);
1234

1235
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1236 1237
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

1238
		if (hists__filter_entry_by_thread(hists, h))
1239
			continue;
1240

1241
		hists__remove_entry_filter(hists, h, HIST_FILTER__THREAD);
1242 1243
	}
}
1244

1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261
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;

1262
	hists->stats.nr_non_filtered_samples = 0;
1263 1264

	hists__reset_filter_stats(hists);
1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276
	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);
	}
}

1277 1278 1279 1280 1281 1282
void events_stats__inc(struct events_stats *stats, u32 type)
{
	++stats->nr_events[0];
	++stats->nr_events[type];
}

1283
void hists__inc_nr_events(struct hists *hists, u32 type)
1284
{
1285
	events_stats__inc(&hists->stats, type);
1286
}
1287

1288 1289 1290 1291 1292 1293 1294
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++;
}

1295 1296 1297
static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
						 struct hist_entry *pair)
{
1298 1299
	struct rb_root *root;
	struct rb_node **p;
1300 1301
	struct rb_node *parent = NULL;
	struct hist_entry *he;
1302
	int64_t cmp;
1303

1304 1305 1306 1307 1308 1309 1310
	if (sort__need_collapse)
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	p = &root->rb_node;

1311 1312
	while (*p != NULL) {
		parent = *p;
1313
		he = rb_entry(parent, struct hist_entry, rb_node_in);
1314

1315
		cmp = hist_entry__collapse(he, pair);
1316 1317 1318 1319 1320 1321 1322 1323 1324 1325

		if (!cmp)
			goto out;

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

1326
	he = hist_entry__new(pair, true);
1327
	if (he) {
1328 1329
		memset(&he->stat, 0, sizeof(he->stat));
		he->hists = hists;
1330 1331
		rb_link_node(&he->rb_node_in, parent, p);
		rb_insert_color(&he->rb_node_in, root);
1332
		hists__inc_stats(hists, he);
1333
		he->dummy = true;
1334 1335 1336 1337 1338
	}
out:
	return he;
}

1339 1340 1341
static struct hist_entry *hists__find_entry(struct hists *hists,
					    struct hist_entry *he)
{
1342 1343 1344 1345 1346 1347
	struct rb_node *n;

	if (sort__need_collapse)
		n = hists->entries_collapsed.rb_node;
	else
		n = hists->entries_in->rb_node;
1348 1349

	while (n) {
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		struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node_in);
		int64_t cmp = hist_entry__collapse(iter, he);
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		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)
{
1369
	struct rb_root *root;
1370 1371 1372
	struct rb_node *nd;
	struct hist_entry *pos, *pair;

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	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);
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		pair = hists__find_entry(other, pos);

		if (pair)
1383
			hist_entry__add_pair(pair, pos);
1384 1385
	}
}
1386 1387 1388 1389 1390 1391 1392 1393

/*
 * 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)
{
1394
	struct rb_root *root;
1395 1396 1397
	struct rb_node *nd;
	struct hist_entry *pos, *pair;

1398 1399 1400 1401 1402 1403 1404
	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);
1405 1406 1407 1408 1409

		if (!hist_entry__has_pairs(pos)) {
			pair = hists__add_dummy_entry(leader, pos);
			if (pair == NULL)
				return -1;
1410
			hist_entry__add_pair(pos, pair);
1411 1412 1413 1414 1415
		}
	}

	return 0;
}
1416

1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431

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;
}


1432 1433 1434 1435 1436
u64 hists__total_period(struct hists *hists)
{
	return symbol_conf.filter_relative ? hists->stats.total_non_filtered_period :
		hists->stats.total_period;
}
N
Namhyung Kim 已提交
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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;
}
1450 1451 1452 1453 1454 1455 1456 1457

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

	return 0;
}
1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485

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;
}