hist.c 33.8 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)
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{
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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;
}

370
static struct hist_entry *add_hist_entry(struct hists *hists,
371
					 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) {
397 398
			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;
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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:
435 436
	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;
}

442
struct hist_entry *__hists__add_entry(struct hists *hists,
443
				      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 = {
462
			.nr_events = 1,
463
			.period	= period,
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			.weight = weight,
465
		},
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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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	};

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	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,
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				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)
{
612
	struct branch_info *bi;
613
	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;

665
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
666
				sample->period, sample->weight,
667
				sample->transaction, true);
668 669 670 671 672 673 674 675
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
	return 0;
}

static int
676 677
iter_finish_normal_entry(struct hist_entry_iter *iter,
			 struct addr_location *al __maybe_unused)
678 679 680 681 682 683 684 685 686 687
{
	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;

688
	hists__inc_nr_samples(evsel__hists(evsel), he->filtered);
689 690 691 692

	return hist_entry__append_callchain(he, sample);
}

693 694 695 696
static int
iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
			      struct addr_location *al __maybe_unused)
{
697 698
	struct hist_entry **he_cache;

699
	callchain_cursor_commit(&callchain_cursor);
700 701 702 703 704 705 706 707 708 709 710 711 712

	/*
	 * 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;

713 714 715 716 717 718 719 720
	return 0;
}

static int
iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
				 struct addr_location *al)
{
	struct perf_evsel *evsel = iter->evsel;
721
	struct hists *hists = evsel__hists(evsel);
722
	struct perf_sample *sample = iter->sample;
723
	struct hist_entry **he_cache = iter->priv;
724 725 726
	struct hist_entry *he;
	int err = 0;

727
	he = __hists__add_entry(hists, al, iter->parent, NULL, NULL,
728 729 730 731 732 733
				sample->period, sample->weight,
				sample->transaction, true);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
734
	he_cache[iter->curr++] = he;
735

736
	hist_entry__append_callchain(he, sample);
737 738 739 740 741 742 743

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

744
	hists__inc_nr_samples(hists, he->filtered);
745 746 747 748 749 750 751 752 753 754 755 756 757 758

	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;

759
	return fill_callchain_info(al, node, iter->hide_unresolved);
760 761 762 763 764 765 766 767
}

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;
768
	struct hist_entry **he_cache = iter->priv;
769
	struct hist_entry *he;
770 771 772 773 774 775 776 777 778 779 780 781
	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;
782 783 784 785 786
	struct callchain_cursor cursor;

	callchain_cursor_snapshot(&cursor, &callchain_cursor);

	callchain_cursor_advance(&callchain_cursor);
787 788 789 790 791 792

	/*
	 * 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++) {
793 794 795
		if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
			/* to avoid calling callback function */
			iter->he = NULL;
796
			return 0;
797
		}
798
	}
799

800
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
801 802 803 804 805 806
				sample->period, sample->weight,
				sample->transaction, false);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
807
	he_cache[iter->curr++] = he;
808

809 810
	if (symbol_conf.use_callchain)
		callchain_append(he->callchain, &cursor, sample->period);
811 812 813 814 815 816 817
	return 0;
}

static int
iter_finish_cumulative_entry(struct hist_entry_iter *iter,
			     struct addr_location *al __maybe_unused)
{
818
	zfree(&iter->priv);
819
	iter->he = NULL;
820

821 822 823
	return 0;
}

824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847
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,
};

848 849 850 851 852 853 854 855
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,
};

856 857
int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
			 struct perf_evsel *evsel, struct perf_sample *sample,
858
			 int max_stack_depth, void *arg)
859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877
{
	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;

878 879 880 881 882 883
	if (iter->he && iter->add_entry_cb) {
		err = iter->add_entry_cb(iter, al, true, arg);
		if (err)
			goto out;
	}

884 885 886 887
	while (iter->ops->next_entry(iter, al)) {
		err = iter->ops->add_next_entry(iter, al);
		if (err)
			break;
888 889 890 891 892 893

		if (iter->he && iter->add_entry_cb) {
			err = iter->add_entry_cb(iter, al, false, arg);
			if (err)
				goto out;
		}
894 895 896 897 898 899 900 901 902 903
	}

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

	return err;
}

904 905 906
int64_t
hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
{
907
	struct perf_hpp_fmt *fmt;
908 909
	int64_t cmp = 0;

910
	perf_hpp__for_each_sort_list(fmt) {
911 912 913
		if (perf_hpp__should_skip(fmt))
			continue;

914
		cmp = fmt->cmp(left, right);
915 916 917 918 919 920 921 922 923 924
		if (cmp)
			break;
	}

	return cmp;
}

int64_t
hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
{
925
	struct perf_hpp_fmt *fmt;
926 927
	int64_t cmp = 0;

928
	perf_hpp__for_each_sort_list(fmt) {
929 930 931
		if (perf_hpp__should_skip(fmt))
			continue;

932
		cmp = fmt->collapse(left, right);
933 934 935 936 937 938 939
		if (cmp)
			break;
	}

	return cmp;
}

940
void hist_entry__delete(struct hist_entry *he)
941
{
942 943
	zfree(&he->branch_info);
	zfree(&he->mem_info);
944
	zfree(&he->stat_acc);
945
	free_srcline(he->srcline);
946
	free_callchain(he->callchain);
947 948 949 950 951 952 953
	free(he);
}

/*
 * collapse the histogram
 */

954
static bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
955 956
					 struct rb_root *root,
					 struct hist_entry *he)
957
{
958
	struct rb_node **p = &root->rb_node;
959 960 961 962 963 964
	struct rb_node *parent = NULL;
	struct hist_entry *iter;
	int64_t cmp;

	while (*p != NULL) {
		parent = *p;
965
		iter = rb_entry(parent, struct hist_entry, rb_node_in);
966 967 968 969

		cmp = hist_entry__collapse(iter, he);

		if (!cmp) {
970
			he_stat__add_stat(&iter->stat, &he->stat);
971 972
			if (symbol_conf.cumulate_callchain)
				he_stat__add_stat(iter->stat_acc, he->stat_acc);
973

974
			if (symbol_conf.use_callchain) {
975 976 977
				callchain_cursor_reset(&callchain_cursor);
				callchain_merge(&callchain_cursor,
						iter->callchain,
978 979
						he->callchain);
			}
980
			hist_entry__delete(he);
981
			return false;
982 983 984 985 986 987 988
		}

		if (cmp < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
989
	hists->nr_entries++;
990

991 992
	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, root);
993
	return true;
994 995
}

996
static struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
997
{
998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010
	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;
}

1011 1012 1013 1014
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);
1015
	hists__filter_entry_by_symbol(hists, he);
1016 1017
}

1018
void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
1019 1020
{
	struct rb_root *root;
1021 1022 1023
	struct rb_node *next;
	struct hist_entry *n;

1024
	if (!sort__need_collapse)
1025 1026
		return;

1027 1028
	hists->nr_entries = 0;

1029
	root = hists__get_rotate_entries_in(hists);
1030

1031
	next = rb_first(root);
1032

1033
	while (next) {
1034 1035
		if (session_done())
			break;
1036 1037
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1038

1039
		rb_erase(&n->rb_node_in, root);
1040 1041 1042 1043 1044 1045 1046 1047
		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);
		}
1048 1049
		if (prog)
			ui_progress__update(prog, 1);
1050
	}
1051
}
1052

1053
static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
1054
{
1055 1056
	struct perf_hpp_fmt *fmt;
	int64_t cmp = 0;
1057

1058
	perf_hpp__for_each_sort_list(fmt) {
1059 1060 1061
		if (perf_hpp__should_skip(fmt))
			continue;

1062 1063
		cmp = fmt->sort(a, b);
		if (cmp)
1064 1065 1066
			break;
	}

1067
	return cmp;
1068 1069
}

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
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;
}

1099 1100 1101
static void __hists__insert_output_entry(struct rb_root *entries,
					 struct hist_entry *he,
					 u64 min_callchain_hits)
1102
{
1103
	struct rb_node **p = &entries->rb_node;
1104 1105 1106
	struct rb_node *parent = NULL;
	struct hist_entry *iter;

1107
	if (symbol_conf.use_callchain)
1108
		callchain_param.sort(&he->sorted_chain, he->callchain,
1109 1110 1111 1112 1113 1114
				      min_callchain_hits, &callchain_param);

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

1115
		if (hist_entry__sort(he, iter) > 0)
1116 1117 1118 1119 1120 1121
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}

	rb_link_node(&he->rb_node, parent, p);
1122
	rb_insert_color(&he->rb_node, entries);
1123 1124
}

1125
void hists__output_resort(struct hists *hists, struct ui_progress *prog)
1126
{
1127
	struct rb_root *root;
1128 1129 1130 1131
	struct rb_node *next;
	struct hist_entry *n;
	u64 min_callchain_hits;

1132
	min_callchain_hits = hists->stats.total_period * (callchain_param.min_percent / 100);
1133

1134
	if (sort__need_collapse)
1135 1136 1137 1138 1139 1140
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	next = rb_first(root);
	hists->entries = RB_ROOT;
1141

1142
	hists__reset_stats(hists);
1143
	hists__reset_col_len(hists);
1144

1145
	while (next) {
1146 1147
		n = rb_entry(next, struct hist_entry, rb_node_in);
		next = rb_next(&n->rb_node_in);
1148

1149
		__hists__insert_output_entry(&hists->entries, n, min_callchain_hits);
1150
		hists__inc_stats(hists, n);
1151 1152 1153

		if (!n->filtered)
			hists__calc_col_len(hists, n);
1154 1155 1156

		if (prog)
			ui_progress__update(prog, 1);
1157
	}
1158
}
1159

1160
static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
1161 1162 1163 1164 1165 1166
				       enum hist_filter filter)
{
	h->filtered &= ~(1 << filter);
	if (h->filtered)
		return;

1167 1168
	/* force fold unfiltered entry for simplicity */
	h->ms.unfolded = false;
1169
	h->row_offset = 0;
1170

1171
	hists->stats.nr_non_filtered_samples += h->stat.nr_events;
1172

1173
	hists__inc_filter_stats(hists, h);
1174
	hists__calc_col_len(hists, h);
1175 1176
}

1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189

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;
}

1190
void hists__filter_by_dso(struct hists *hists)
1191 1192 1193
{
	struct rb_node *nd;

1194
	hists->stats.nr_non_filtered_samples = 0;
1195 1196

	hists__reset_filter_stats(hists);
1197
	hists__reset_col_len(hists);
1198

1199
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1200 1201 1202 1203 1204
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

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

1205
		if (hists__filter_entry_by_dso(hists, h))
1206 1207
			continue;

1208
		hists__remove_entry_filter(hists, h, HIST_FILTER__DSO);
1209 1210 1211
	}
}

1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223
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;
}

1224
void hists__filter_by_thread(struct hists *hists)
1225 1226 1227
{
	struct rb_node *nd;

1228
	hists->stats.nr_non_filtered_samples = 0;
1229 1230

	hists__reset_filter_stats(hists);
1231
	hists__reset_col_len(hists);
1232

1233
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1234 1235
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

1236
		if (hists__filter_entry_by_thread(hists, h))
1237
			continue;
1238

1239
		hists__remove_entry_filter(hists, h, HIST_FILTER__THREAD);
1240 1241
	}
}
1242

1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259
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;

1260
	hists->stats.nr_non_filtered_samples = 0;
1261 1262

	hists__reset_filter_stats(hists);
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
	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);
	}
}

1275 1276 1277 1278 1279 1280
void events_stats__inc(struct events_stats *stats, u32 type)
{
	++stats->nr_events[0];
	++stats->nr_events[type];
}

1281
void hists__inc_nr_events(struct hists *hists, u32 type)
1282
{
1283
	events_stats__inc(&hists->stats, type);
1284
}
1285

1286 1287 1288 1289 1290 1291 1292
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++;
}

1293 1294 1295
static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
						 struct hist_entry *pair)
{
1296 1297
	struct rb_root *root;
	struct rb_node **p;
1298 1299
	struct rb_node *parent = NULL;
	struct hist_entry *he;
1300
	int64_t cmp;
1301

1302 1303 1304 1305 1306 1307 1308
	if (sort__need_collapse)
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	p = &root->rb_node;

1309 1310
	while (*p != NULL) {
		parent = *p;
1311
		he = rb_entry(parent, struct hist_entry, rb_node_in);
1312

1313
		cmp = hist_entry__collapse(he, pair);
1314 1315 1316 1317 1318 1319 1320 1321 1322 1323

		if (!cmp)
			goto out;

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

1324
	he = hist_entry__new(pair, true);
1325
	if (he) {
1326 1327
		memset(&he->stat, 0, sizeof(he->stat));
		he->hists = hists;
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		rb_link_node(&he->rb_node_in, parent, p);
		rb_insert_color(&he->rb_node_in, root);
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		hists__inc_stats(hists, he);
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		he->dummy = true;
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	}
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;
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	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)
{
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	struct rb_root *root;
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	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)
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			hist_entry__add_pair(pair, pos);
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	}
}
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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)
{
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	struct rb_root *root;
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	struct rb_node *nd;
	struct hist_entry *pos, *pair;

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	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);
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		if (!hist_entry__has_pairs(pos)) {
			pair = hists__add_dummy_entry(leader, pos);
			if (pair == NULL)
				return -1;
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			hist_entry__add_pair(pos, pair);
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		}
	}

	return 0;
}
1414

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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;
}


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

	return 0;
}
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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;
}