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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Don Zickus 已提交
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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)
229
		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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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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			rb_erase(&n->rb_node, &hists->entries);

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			if (sort__need_collapse)
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				rb_erase(&n->rb_node_in, &hists->entries_collapsed);

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

			hist_entry__free(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);

		rb_erase(&n->rb_node, &hists->entries);

		if (sort__need_collapse)
			rb_erase(&n->rb_node_in, &hists->entries_collapsed);

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

		hist_entry__free(n);
	}
}

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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)
303
{
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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;
		}

358
		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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	}

364
	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;
}

374
static struct hist_entry *add_hist_entry(struct hists *hists,
375
					 struct hist_entry *entry,
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					 struct addr_location *al,
					 bool sample_self)
378
{
379
	struct rb_node **p;
380 381
	struct rb_node *parent = NULL;
	struct hist_entry *he;
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	int64_t cmp;
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	u64 period = entry->stat.period;
	u64 weight = entry->stat.weight;
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	p = &hists->entries_in->rb_node;

388 389
	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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406
			/*
407
			 * This mem info was allocated from sample__resolve_mem
408 409
			 * and will not be used anymore.
			 */
410
			zfree(&entry->mem_info);
411

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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;
			}
423
			goto out;
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		}

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

432
	he = hist_entry__new(entry, sample_self);
433
	if (!he)
434
		return NULL;
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	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, hists->entries_in);
438
out:
439 440
	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;
}

446
struct hist_entry *__hists__add_entry(struct hists *hists,
447
				      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,
456
		.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,
469
		},
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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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	};

478
	return add_hist_entry(hists, &entry, al, sample_self);
479 480
}

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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.
	 */
531
	he = __hists__add_entry(hists, al, iter->parent, NULL, mi,
532
				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)
{
616
	struct branch_info *bi;
617
	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.
	 */
632
	he = __hists__add_entry(hists, al, iter->parent, &bi[i], NULL,
633
				1, 1, 0, true);
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	if (he == NULL)
		return -ENOMEM;

637
	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;

669
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
670
				sample->period, sample->weight,
671
				sample->transaction, true);
672 673 674 675 676 677 678 679
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
	return 0;
}

static int
680 681
iter_finish_normal_entry(struct hist_entry_iter *iter,
			 struct addr_location *al __maybe_unused)
682 683 684 685 686 687 688 689 690 691
{
	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;

692
	hists__inc_nr_samples(evsel__hists(evsel), he->filtered);
693 694 695 696

	return hist_entry__append_callchain(he, sample);
}

697 698 699 700
static int
iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
			      struct addr_location *al __maybe_unused)
{
701 702
	struct hist_entry **he_cache;

703
	callchain_cursor_commit(&callchain_cursor);
704 705 706 707 708 709 710 711 712 713 714 715 716

	/*
	 * 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;

717 718 719 720 721 722 723 724
	return 0;
}

static int
iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
				 struct addr_location *al)
{
	struct perf_evsel *evsel = iter->evsel;
725
	struct hists *hists = evsel__hists(evsel);
726
	struct perf_sample *sample = iter->sample;
727
	struct hist_entry **he_cache = iter->priv;
728 729 730
	struct hist_entry *he;
	int err = 0;

731
	he = __hists__add_entry(hists, al, iter->parent, NULL, NULL,
732 733 734 735 736 737
				sample->period, sample->weight,
				sample->transaction, true);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
738
	he_cache[iter->curr++] = he;
739

740
	hist_entry__append_callchain(he, sample);
741 742 743 744 745 746 747

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

748
	hists__inc_nr_samples(hists, he->filtered);
749 750 751 752 753 754 755 756 757 758 759 760 761 762

	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;

763
	return fill_callchain_info(al, node, iter->hide_unresolved);
764 765 766 767 768 769 770 771
}

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;
772
	struct hist_entry **he_cache = iter->priv;
773
	struct hist_entry *he;
774 775 776 777 778 779 780 781 782 783 784 785
	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;
786 787 788 789 790
	struct callchain_cursor cursor;

	callchain_cursor_snapshot(&cursor, &callchain_cursor);

	callchain_cursor_advance(&callchain_cursor);
791 792 793 794 795 796

	/*
	 * 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++) {
797 798 799
		if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
			/* to avoid calling callback function */
			iter->he = NULL;
800
			return 0;
801
		}
802
	}
803

804
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
805 806 807 808 809 810
				sample->period, sample->weight,
				sample->transaction, false);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
811
	he_cache[iter->curr++] = he;
812

813 814
	if (symbol_conf.use_callchain)
		callchain_append(he->callchain, &cursor, sample->period);
815 816 817 818 819 820 821
	return 0;
}

static int
iter_finish_cumulative_entry(struct hist_entry_iter *iter,
			     struct addr_location *al __maybe_unused)
{
822
	zfree(&iter->priv);
823
	iter->he = NULL;
824

825 826 827
	return 0;
}

828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
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,
};

852 853 854 855 856 857 858 859
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,
};

860 861
int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
			 struct perf_evsel *evsel, struct perf_sample *sample,
862
			 int max_stack_depth, void *arg)
863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
{
	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;

882 883 884 885 886 887
	if (iter->he && iter->add_entry_cb) {
		err = iter->add_entry_cb(iter, al, true, arg);
		if (err)
			goto out;
	}

888 889 890 891
	while (iter->ops->next_entry(iter, al)) {
		err = iter->ops->add_next_entry(iter, al);
		if (err)
			break;
892 893 894 895 896 897

		if (iter->he && iter->add_entry_cb) {
			err = iter->add_entry_cb(iter, al, false, arg);
			if (err)
				goto out;
		}
898 899 900 901 902 903 904 905 906 907
	}

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

	return err;
}

908 909 910
int64_t
hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
{
911
	struct perf_hpp_fmt *fmt;
912 913
	int64_t cmp = 0;

914
	perf_hpp__for_each_sort_list(fmt) {
915 916 917
		if (perf_hpp__should_skip(fmt))
			continue;

918
		cmp = fmt->cmp(left, right);
919 920 921 922 923 924 925 926 927 928
		if (cmp)
			break;
	}

	return cmp;
}

int64_t
hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
{
929
	struct perf_hpp_fmt *fmt;
930 931
	int64_t cmp = 0;

932
	perf_hpp__for_each_sort_list(fmt) {
933 934 935
		if (perf_hpp__should_skip(fmt))
			continue;

936
		cmp = fmt->collapse(left, right);
937 938 939 940 941 942 943 944 945
		if (cmp)
			break;
	}

	return cmp;
}

void hist_entry__free(struct hist_entry *he)
{
946 947
	zfree(&he->branch_info);
	zfree(&he->mem_info);
948
	zfree(&he->stat_acc);
949
	free_srcline(he->srcline);
950
	free_callchain(he->callchain);
951 952 953 954 955 956 957
	free(he);
}

/*
 * collapse the histogram
 */

958
static bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
959 960
					 struct rb_root *root,
					 struct hist_entry *he)
961
{
962
	struct rb_node **p = &root->rb_node;
963 964 965 966 967 968
	struct rb_node *parent = NULL;
	struct hist_entry *iter;
	int64_t cmp;

	while (*p != NULL) {
		parent = *p;
969
		iter = rb_entry(parent, struct hist_entry, rb_node_in);
970 971 972 973

		cmp = hist_entry__collapse(iter, he);

		if (!cmp) {
974
			he_stat__add_stat(&iter->stat, &he->stat);
975 976
			if (symbol_conf.cumulate_callchain)
				he_stat__add_stat(iter->stat_acc, he->stat_acc);
977

978
			if (symbol_conf.use_callchain) {
979 980 981
				callchain_cursor_reset(&callchain_cursor);
				callchain_merge(&callchain_cursor,
						iter->callchain,
982 983
						he->callchain);
			}
984
			hist_entry__free(he);
985
			return false;
986 987 988 989 990 991 992
		}

		if (cmp < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
993
	hists->nr_entries++;
994

995 996
	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, root);
997
	return true;
998 999
}

1000
static struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
1001
{
1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014
	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;
}

1015 1016 1017 1018
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);
1019
	hists__filter_entry_by_symbol(hists, he);
1020 1021
}

1022
void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
1023 1024
{
	struct rb_root *root;
1025 1026 1027
	struct rb_node *next;
	struct hist_entry *n;

1028
	if (!sort__need_collapse)
1029 1030
		return;

1031 1032
	hists->nr_entries = 0;

1033
	root = hists__get_rotate_entries_in(hists);
1034

1035
	next = rb_first(root);
1036

1037
	while (next) {
1038 1039
		if (session_done())
			break;
1040 1041
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1042

1043
		rb_erase(&n->rb_node_in, root);
1044 1045 1046 1047 1048 1049 1050 1051
		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);
		}
1052 1053
		if (prog)
			ui_progress__update(prog, 1);
1054
	}
1055
}
1056

1057
static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
1058
{
1059 1060
	struct perf_hpp_fmt *fmt;
	int64_t cmp = 0;
1061

1062
	perf_hpp__for_each_sort_list(fmt) {
1063 1064 1065
		if (perf_hpp__should_skip(fmt))
			continue;

1066 1067
		cmp = fmt->sort(a, b);
		if (cmp)
1068 1069 1070
			break;
	}

1071
	return cmp;
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 1101 1102
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;
}

1103 1104 1105
static void __hists__insert_output_entry(struct rb_root *entries,
					 struct hist_entry *he,
					 u64 min_callchain_hits)
1106
{
1107
	struct rb_node **p = &entries->rb_node;
1108 1109 1110
	struct rb_node *parent = NULL;
	struct hist_entry *iter;

1111
	if (symbol_conf.use_callchain)
1112
		callchain_param.sort(&he->sorted_chain, he->callchain,
1113 1114 1115 1116 1117 1118
				      min_callchain_hits, &callchain_param);

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

1119
		if (hist_entry__sort(he, iter) > 0)
1120 1121 1122 1123 1124 1125
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}

	rb_link_node(&he->rb_node, parent, p);
1126
	rb_insert_color(&he->rb_node, entries);
1127 1128
}

1129
void hists__output_resort(struct hists *hists, struct ui_progress *prog)
1130
{
1131
	struct rb_root *root;
1132 1133 1134 1135
	struct rb_node *next;
	struct hist_entry *n;
	u64 min_callchain_hits;

1136
	min_callchain_hits = hists->stats.total_period * (callchain_param.min_percent / 100);
1137

1138
	if (sort__need_collapse)
1139 1140 1141 1142 1143 1144
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	next = rb_first(root);
	hists->entries = RB_ROOT;
1145

1146
	hists__reset_stats(hists);
1147
	hists__reset_col_len(hists);
1148

1149
	while (next) {
1150 1151
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1152

1153
		__hists__insert_output_entry(&hists->entries, n, min_callchain_hits);
1154
		hists__inc_stats(hists, n);
1155 1156 1157

		if (!n->filtered)
			hists__calc_col_len(hists, n);
1158 1159 1160

		if (prog)
			ui_progress__update(prog, 1);
1161
	}
1162
}
1163

1164
static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
1165 1166 1167 1168 1169 1170
				       enum hist_filter filter)
{
	h->filtered &= ~(1 << filter);
	if (h->filtered)
		return;

1171 1172
	/* force fold unfiltered entry for simplicity */
	h->ms.unfolded = false;
1173
	h->row_offset = 0;
1174

1175
	hists->stats.nr_non_filtered_samples += h->stat.nr_events;
1176

1177
	hists__inc_filter_stats(hists, h);
1178
	hists__calc_col_len(hists, h);
1179 1180
}

1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193

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;
}

1194
void hists__filter_by_dso(struct hists *hists)
1195 1196 1197
{
	struct rb_node *nd;

1198
	hists->stats.nr_non_filtered_samples = 0;
1199 1200

	hists__reset_filter_stats(hists);
1201
	hists__reset_col_len(hists);
1202

1203
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1204 1205 1206 1207 1208
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

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

1209
		if (hists__filter_entry_by_dso(hists, h))
1210 1211
			continue;

1212
		hists__remove_entry_filter(hists, h, HIST_FILTER__DSO);
1213 1214 1215
	}
}

1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227
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;
}

1228
void hists__filter_by_thread(struct hists *hists)
1229 1230 1231
{
	struct rb_node *nd;

1232
	hists->stats.nr_non_filtered_samples = 0;
1233 1234

	hists__reset_filter_stats(hists);
1235
	hists__reset_col_len(hists);
1236

1237
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1238 1239
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

1240
		if (hists__filter_entry_by_thread(hists, h))
1241
			continue;
1242

1243
		hists__remove_entry_filter(hists, h, HIST_FILTER__THREAD);
1244 1245
	}
}
1246

1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
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;

1264
	hists->stats.nr_non_filtered_samples = 0;
1265 1266

	hists__reset_filter_stats(hists);
1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278
	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);
	}
}

1279 1280 1281 1282 1283 1284
void events_stats__inc(struct events_stats *stats, u32 type)
{
	++stats->nr_events[0];
	++stats->nr_events[type];
}

1285
void hists__inc_nr_events(struct hists *hists, u32 type)
1286
{
1287
	events_stats__inc(&hists->stats, type);
1288
}
1289

1290 1291 1292 1293 1294 1295 1296
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++;
}

1297 1298 1299
static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
						 struct hist_entry *pair)
{
1300 1301
	struct rb_root *root;
	struct rb_node **p;
1302 1303
	struct rb_node *parent = NULL;
	struct hist_entry *he;
1304
	int64_t cmp;
1305

1306 1307 1308 1309 1310 1311 1312
	if (sort__need_collapse)
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	p = &root->rb_node;

1313 1314
	while (*p != NULL) {
		parent = *p;
1315
		he = rb_entry(parent, struct hist_entry, rb_node_in);
1316

1317
		cmp = hist_entry__collapse(he, pair);
1318 1319 1320 1321 1322 1323 1324 1325 1326 1327

		if (!cmp)
			goto out;

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

1328
	he = hist_entry__new(pair, true);
1329
	if (he) {
1330 1331
		memset(&he->stat, 0, sizeof(he->stat));
		he->hists = hists;
1332 1333
		rb_link_node(&he->rb_node_in, parent, p);
		rb_insert_color(&he->rb_node_in, root);
1334
		hists__inc_stats(hists, he);
1335
		he->dummy = true;
1336 1337 1338 1339 1340
	}
out:
	return he;
}

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

	if (sort__need_collapse)
		n = hists->entries_collapsed.rb_node;
	else
		n = hists->entries_in->rb_node;
1350 1351

	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)
{
1371
	struct rb_root *root;
1372 1373 1374
	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)
1385
			hist_entry__add_pair(pair, pos);
1386 1387
	}
}
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/*
 * 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)
{
1396
	struct rb_root *root;
1397 1398 1399
	struct rb_node *nd;
	struct hist_entry *pos, *pair;

1400 1401 1402 1403 1404 1405 1406
	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);
1407 1408 1409 1410 1411

		if (!hist_entry__has_pairs(pos)) {
			pair = hists__add_dummy_entry(leader, pos);
			if (pair == NULL)
				return -1;
1412
			hist_entry__add_pair(pos, pair);
1413 1414 1415 1416 1417
		}
	}

	return 0;
}
1418

1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433

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;
}


1434 1435 1436 1437 1438
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;
}
1452 1453 1454 1455 1456 1457 1458 1459

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

	return 0;
}
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 1486 1487

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;
}