hist.c 33.7 KB
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#include "util.h"
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#include "build-id.h"
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#include "hist.h"
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#include "session.h"
#include "sort.h"
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#include "evlist.h"
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#include "evsel.h"
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#include "annotate.h"
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#include "ui/progress.h"
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#include <math.h>
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static bool hists__filter_entry_by_dso(struct hists *hists,
				       struct hist_entry *he);
static bool hists__filter_entry_by_thread(struct hists *hists,
					  struct hist_entry *he);
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static bool hists__filter_entry_by_symbol(struct hists *hists,
					  struct hist_entry *he);
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u16 hists__col_len(struct hists *hists, enum hist_column col)
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{
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	return hists->col_len[col];
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}

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

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

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

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

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static void hists__set_unres_dso_col_len(struct hists *hists, int dso)
{
	const unsigned int unresolved_col_width = BITS_PER_LONG / 4;

	if (hists__col_len(hists, dso) < unresolved_col_width &&
	    !symbol_conf.col_width_list_str && !symbol_conf.field_sep &&
	    !symbol_conf.dso_list)
		hists__set_col_len(hists, dso, unresolved_col_width);
}

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

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	/*
	 * +4 accounts for '[x] ' priv level info
	 * +2 accounts for 0x prefix on raw addresses
	 * +3 accounts for ' y ' symtab origin info
	 */
	if (h->ms.sym) {
		symlen = h->ms.sym->namelen + 4;
		if (verbose)
			symlen += BITS_PER_LONG / 4 + 2 + 3;
		hists__new_col_len(hists, HISTC_SYMBOL, symlen);
	} else {
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		symlen = unresolved_col_width + 4 + 2;
		hists__new_col_len(hists, HISTC_SYMBOL, symlen);
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		hists__set_unres_dso_col_len(hists, HISTC_DSO);
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	}
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	len = thread__comm_len(h->thread);
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	if (hists__new_col_len(hists, HISTC_COMM, len))
		hists__set_col_len(hists, HISTC_THREAD, len + 6);
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	if (h->ms.map) {
		len = dso__name_len(h->ms.map->dso);
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		hists__new_col_len(hists, HISTC_DSO, len);
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	}
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	if (h->parent)
		hists__new_col_len(hists, HISTC_PARENT, h->parent->namelen);

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	if (h->branch_info) {
		if (h->branch_info->from.sym) {
			symlen = (int)h->branch_info->from.sym->namelen + 4;
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			if (verbose)
				symlen += BITS_PER_LONG / 4 + 2 + 3;
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			hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);

			symlen = dso__name_len(h->branch_info->from.map->dso);
			hists__new_col_len(hists, HISTC_DSO_FROM, symlen);
		} else {
			symlen = unresolved_col_width + 4 + 2;
			hists__new_col_len(hists, HISTC_SYMBOL_FROM, symlen);
			hists__set_unres_dso_col_len(hists, HISTC_DSO_FROM);
		}

		if (h->branch_info->to.sym) {
			symlen = (int)h->branch_info->to.sym->namelen + 4;
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			if (verbose)
				symlen += BITS_PER_LONG / 4 + 2 + 3;
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			hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);

			symlen = dso__name_len(h->branch_info->to.map->dso);
			hists__new_col_len(hists, HISTC_DSO_TO, symlen);
		} else {
			symlen = unresolved_col_width + 4 + 2;
			hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);
			hists__set_unres_dso_col_len(hists, HISTC_DSO_TO);
		}
	}
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	if (h->mem_info) {
		if (h->mem_info->daddr.sym) {
			symlen = (int)h->mem_info->daddr.sym->namelen + 4
			       + unresolved_col_width + 2;
			hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
					   symlen);
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			hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
					   symlen + 1);
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		} else {
			symlen = unresolved_col_width + 4 + 2;
			hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
					   symlen);
		}
		if (h->mem_info->daddr.map) {
			symlen = dso__name_len(h->mem_info->daddr.map->dso);
			hists__new_col_len(hists, HISTC_MEM_DADDR_DSO,
					   symlen);
		} else {
			symlen = unresolved_col_width + 4 + 2;
			hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
		}
	} else {
		symlen = unresolved_col_width + 4 + 2;
		hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL, symlen);
		hists__set_unres_dso_col_len(hists, HISTC_MEM_DADDR_DSO);
	}

	hists__new_col_len(hists, HISTC_MEM_LOCKED, 6);
	hists__new_col_len(hists, HISTC_MEM_TLB, 22);
	hists__new_col_len(hists, HISTC_MEM_SNOOP, 12);
	hists__new_col_len(hists, HISTC_MEM_LVL, 21 + 3);
	hists__new_col_len(hists, HISTC_LOCAL_WEIGHT, 12);
	hists__new_col_len(hists, HISTC_GLOBAL_WEIGHT, 12);
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	if (h->transaction)
		hists__new_col_len(hists, HISTC_TRANSACTION,
				   hist_entry__transaction_len());
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}

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void hists__output_recalc_col_len(struct hists *hists, int max_rows)
{
	struct rb_node *next = rb_first(&hists->entries);
	struct hist_entry *n;
	int row = 0;

	hists__reset_col_len(hists);

	while (next && row++ < max_rows) {
		n = rb_entry(next, struct hist_entry, rb_node);
		if (!n->filtered)
			hists__calc_col_len(hists, n);
		next = rb_next(&n->rb_node);
	}
}

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

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static void he_stat__add_period(struct he_stat *he_stat, u64 period,
				u64 weight)
198
{
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	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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		if (((zap_user && n->level == '.') ||
		     (zap_kernel && n->level != '.') ||
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		     hists__decay_entry(hists, n))) {
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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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		map__get(he->ms.map);
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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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				map__zput(he->ms.map);
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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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			map__get(he->branch_info->from.map);
			map__get(he->branch_info->to.map);
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		}

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		if (he->mem_info) {
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			map__get(he->mem_info->iaddr.map);
			map__get(he->mem_info->daddr.map);
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		}

344
		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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		thread__get(he->thread);
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	}

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	return he;
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}

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

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static struct hist_entry *hists__findnew_entry(struct hists *hists,
					       struct hist_entry *entry,
					       struct addr_location *al,
					       bool sample_self)
365
{
366
	struct rb_node **p;
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	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;

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	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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393
			/*
394
			 * This mem info was allocated from sample__resolve_mem
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			 * and will not be used anymore.
			 */
397
			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) {
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				map__put(he->ms.map);
				he->ms.map = map__get(entry->ms.map);
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			}
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			goto out;
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		}

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

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	he = hist_entry__new(entry, sample_self);
419
	if (!he)
420
		return NULL;
421

422 423
	hists->nr_entries++;

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	rb_link_node(&he->rb_node_in, parent, p);
	rb_insert_color(&he->rb_node_in, hists->entries_in);
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out:
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	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;
}

434
struct hist_entry *__hists__add_entry(struct hists *hists,
435
				      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,
444
		.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 = {
454
			.nr_events = 1,
455
			.period	= period,
456
			.weight = weight,
457
		},
458
		.parent = sym_parent,
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		.filtered = symbol__parent_filter(sym_parent) | al->filtered,
460
		.hists	= hists,
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		.branch_info = bi,
		.mem_info = mi,
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		.transaction = transaction,
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	};

466
	return hists__findnew_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,
520
				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:
	/*
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	 * We don't need to free iter->priv (mem_info) here since the mem info
	 * was either already freed in hists__findnew_entry() or passed to a
	 * new hist entry by hist_entry__new().
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	 */
	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)
{
604
	struct branch_info *bi;
605
	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, bi->flags.cycles ? bi->flags.cycles : 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;

658
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
659
				sample->period, sample->weight,
660
				sample->transaction, true);
661 662 663 664 665 666 667 668
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
	return 0;
}

static int
669 670
iter_finish_normal_entry(struct hist_entry_iter *iter,
			 struct addr_location *al __maybe_unused)
671 672 673 674 675 676 677 678 679 680
{
	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;

681
	hists__inc_nr_samples(evsel__hists(evsel), he->filtered);
682 683 684 685

	return hist_entry__append_callchain(he, sample);
}

686 687 688 689
static int
iter_prepare_cumulative_entry(struct hist_entry_iter *iter __maybe_unused,
			      struct addr_location *al __maybe_unused)
{
690 691
	struct hist_entry **he_cache;

692
	callchain_cursor_commit(&callchain_cursor);
693 694 695 696 697 698 699 700 701 702 703 704 705

	/*
	 * 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;

706 707 708 709 710 711 712 713
	return 0;
}

static int
iter_add_single_cumulative_entry(struct hist_entry_iter *iter,
				 struct addr_location *al)
{
	struct perf_evsel *evsel = iter->evsel;
714
	struct hists *hists = evsel__hists(evsel);
715
	struct perf_sample *sample = iter->sample;
716
	struct hist_entry **he_cache = iter->priv;
717 718 719
	struct hist_entry *he;
	int err = 0;

720
	he = __hists__add_entry(hists, al, iter->parent, NULL, NULL,
721 722 723 724 725 726
				sample->period, sample->weight,
				sample->transaction, true);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
727
	he_cache[iter->curr++] = he;
728

729
	hist_entry__append_callchain(he, sample);
730 731 732 733 734 735 736

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

737
	hists__inc_nr_samples(hists, he->filtered);
738 739 740 741 742 743 744 745 746 747 748 749 750 751

	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;

752
	return fill_callchain_info(al, node, iter->hide_unresolved);
753 754 755 756 757 758 759 760
}

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;
761
	struct hist_entry **he_cache = iter->priv;
762
	struct hist_entry *he;
763 764 765 766 767 768 769 770 771 772 773 774
	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;
775 776 777 778 779
	struct callchain_cursor cursor;

	callchain_cursor_snapshot(&cursor, &callchain_cursor);

	callchain_cursor_advance(&callchain_cursor);
780 781 782 783 784 785

	/*
	 * 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++) {
786 787 788
		if (hist_entry__cmp(he_cache[i], &he_tmp) == 0) {
			/* to avoid calling callback function */
			iter->he = NULL;
789
			return 0;
790
		}
791
	}
792

793
	he = __hists__add_entry(evsel__hists(evsel), al, iter->parent, NULL, NULL,
794 795 796 797 798 799
				sample->period, sample->weight,
				sample->transaction, false);
	if (he == NULL)
		return -ENOMEM;

	iter->he = he;
800
	he_cache[iter->curr++] = he;
801

802 803
	if (symbol_conf.use_callchain)
		callchain_append(he->callchain, &cursor, sample->period);
804 805 806 807 808 809 810
	return 0;
}

static int
iter_finish_cumulative_entry(struct hist_entry_iter *iter,
			     struct addr_location *al __maybe_unused)
{
811
	zfree(&iter->priv);
812
	iter->he = NULL;
813

814 815 816
	return 0;
}

817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
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,
};

841 842 843 844 845 846 847 848
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,
};

849
int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
850
			 int max_stack_depth, void *arg)
851 852 853
{
	int err, err2;

854 855
	err = sample__resolve_callchain(iter->sample, &iter->parent,
					iter->evsel, al, max_stack_depth);
856 857 858 859 860 861 862 863 864 865 866
	if (err)
		return err;

	err = iter->ops->prepare_entry(iter, al);
	if (err)
		goto out;

	err = iter->ops->add_single_entry(iter, al);
	if (err)
		goto out;

867 868 869 870 871 872
	if (iter->he && iter->add_entry_cb) {
		err = iter->add_entry_cb(iter, al, true, arg);
		if (err)
			goto out;
	}

873 874 875 876
	while (iter->ops->next_entry(iter, al)) {
		err = iter->ops->add_next_entry(iter, al);
		if (err)
			break;
877 878 879 880 881 882

		if (iter->he && iter->add_entry_cb) {
			err = iter->add_entry_cb(iter, al, false, arg);
			if (err)
				goto out;
		}
883 884 885 886 887 888 889 890 891 892
	}

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

	return err;
}

893 894 895
int64_t
hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
{
896
	struct perf_hpp_fmt *fmt;
897 898
	int64_t cmp = 0;

899
	perf_hpp__for_each_sort_list(fmt) {
900 901 902
		if (perf_hpp__should_skip(fmt))
			continue;

903
		cmp = fmt->cmp(fmt, left, right);
904 905 906 907 908 909 910 911 912 913
		if (cmp)
			break;
	}

	return cmp;
}

int64_t
hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
{
914
	struct perf_hpp_fmt *fmt;
915 916
	int64_t cmp = 0;

917
	perf_hpp__for_each_sort_list(fmt) {
918 919 920
		if (perf_hpp__should_skip(fmt))
			continue;

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

	return cmp;
}

929
void hist_entry__delete(struct hist_entry *he)
930
{
931
	thread__zput(he->thread);
932 933 934 935 936 937 938 939 940 941 942 943 944 945
	map__zput(he->ms.map);

	if (he->branch_info) {
		map__zput(he->branch_info->from.map);
		map__zput(he->branch_info->to.map);
		zfree(&he->branch_info);
	}

	if (he->mem_info) {
		map__zput(he->mem_info->iaddr.map);
		map__zput(he->mem_info->daddr.map);
		zfree(&he->mem_info);
	}

946
	zfree(&he->stat_acc);
947
	free_srcline(he->srcline);
948
	free_callchain(he->callchain);
949 950 951 952 953 954 955
	free(he);
}

/*
 * collapse the histogram
 */

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

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

		cmp = hist_entry__collapse(iter, he);

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

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

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

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

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

	pthread_mutex_lock(&hists->lock);

	root = hists->entries_in;
	if (++hists->entries_in > &hists->entries_in_array[1])
		hists->entries_in = &hists->entries_in_array[0];

	pthread_mutex_unlock(&hists->lock);

	return root;
}

1013 1014 1015 1016
static void hists__apply_filters(struct hists *hists, struct hist_entry *he)
{
	hists__filter_entry_by_dso(hists, he);
	hists__filter_entry_by_thread(hists, he);
1017
	hists__filter_entry_by_symbol(hists, he);
1018 1019
}

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

1026
	if (!sort__need_collapse)
1027 1028
		return;

1029 1030
	hists->nr_entries = 0;

1031
	root = hists__get_rotate_entries_in(hists);
1032

1033
	next = rb_first(root);
1034

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

1041
		rb_erase(&n->rb_node_in, root);
1042 1043 1044 1045 1046 1047 1048 1049
		if (hists__collapse_insert_entry(hists, &hists->entries_collapsed, n)) {
			/*
			 * If it wasn't combined with one of the entries already
			 * collapsed, we need to apply the filters that may have
			 * been set by, say, the hist_browser.
			 */
			hists__apply_filters(hists, n);
		}
1050 1051
		if (prog)
			ui_progress__update(prog, 1);
1052
	}
1053
}
1054

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

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

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

1069
	return cmp;
1070 1071
}

1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100
static void hists__reset_filter_stats(struct hists *hists)
{
	hists->nr_non_filtered_entries = 0;
	hists->stats.total_non_filtered_period = 0;
}

void hists__reset_stats(struct hists *hists)
{
	hists->nr_entries = 0;
	hists->stats.total_period = 0;

	hists__reset_filter_stats(hists);
}

static void hists__inc_filter_stats(struct hists *hists, struct hist_entry *h)
{
	hists->nr_non_filtered_entries++;
	hists->stats.total_non_filtered_period += h->stat.period;
}

void hists__inc_stats(struct hists *hists, struct hist_entry *h)
{
	if (!h->filtered)
		hists__inc_filter_stats(hists, h);

	hists->nr_entries++;
	hists->stats.total_period += h->stat.period;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

1169
	/* force fold unfiltered entry for simplicity */
1170
	h->unfolded = false;
1171
	h->row_offset = 0;
1172
	h->nr_rows = 0;
1173

1174
	hists->stats.nr_non_filtered_samples += h->stat.nr_events;
1175

1176
	hists__inc_filter_stats(hists, h);
1177
	hists__calc_col_len(hists, h);
1178 1179
}

1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192

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;
}

1193
void hists__filter_by_dso(struct hists *hists)
1194 1195 1196
{
	struct rb_node *nd;

1197
	hists->stats.nr_non_filtered_samples = 0;
1198 1199

	hists__reset_filter_stats(hists);
1200
	hists__reset_col_len(hists);
1201

1202
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1203 1204 1205 1206 1207
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

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

1208
		if (hists__filter_entry_by_dso(hists, h))
1209 1210
			continue;

1211
		hists__remove_entry_filter(hists, h, HIST_FILTER__DSO);
1212 1213 1214
	}
}

1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226
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;
}

1227
void hists__filter_by_thread(struct hists *hists)
1228 1229 1230
{
	struct rb_node *nd;

1231
	hists->stats.nr_non_filtered_samples = 0;
1232 1233

	hists__reset_filter_stats(hists);
1234
	hists__reset_col_len(hists);
1235

1236
	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
1237 1238
		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);

1239
		if (hists__filter_entry_by_thread(hists, h))
1240
			continue;
1241

1242
		hists__remove_entry_filter(hists, h, HIST_FILTER__THREAD);
1243 1244
	}
}
1245

1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262
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;

1263
	hists->stats.nr_non_filtered_samples = 0;
1264 1265

	hists__reset_filter_stats(hists);
1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277
	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);
	}
}

1278 1279 1280 1281 1282 1283
void events_stats__inc(struct events_stats *stats, u32 type)
{
	++stats->nr_events[0];
	++stats->nr_events[type];
}

1284
void hists__inc_nr_events(struct hists *hists, u32 type)
1285
{
1286
	events_stats__inc(&hists->stats, type);
1287
}
1288

1289 1290 1291 1292 1293 1294 1295
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++;
}

1296 1297 1298
static struct hist_entry *hists__add_dummy_entry(struct hists *hists,
						 struct hist_entry *pair)
{
1299 1300
	struct rb_root *root;
	struct rb_node **p;
1301 1302
	struct rb_node *parent = NULL;
	struct hist_entry *he;
1303
	int64_t cmp;
1304

1305 1306 1307 1308 1309 1310 1311
	if (sort__need_collapse)
		root = &hists->entries_collapsed;
	else
		root = hists->entries_in;

	p = &root->rb_node;

1312 1313
	while (*p != NULL) {
		parent = *p;
1314
		he = rb_entry(parent, struct hist_entry, rb_node_in);
1315

1316
		cmp = hist_entry__collapse(he, pair);
1317 1318 1319 1320 1321 1322 1323 1324 1325 1326

		if (!cmp)
			goto out;

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

1327
	he = hist_entry__new(pair, true);
1328
	if (he) {
1329 1330
		memset(&he->stat, 0, sizeof(he->stat));
		he->hists = hists;
1331 1332
		rb_link_node(&he->rb_node_in, parent, p);
		rb_insert_color(&he->rb_node_in, root);
1333
		hists__inc_stats(hists, he);
1334
		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;
1349 1350

	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;
1371 1372 1373
	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);
1385 1386
	}
}
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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);
1406 1407 1408 1409 1410

		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;
}
1417

1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432

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;
}


1433 1434 1435 1436 1437
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;
}
1451 1452 1453 1454 1455 1456 1457 1458

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

	return 0;
}
1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486

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;
}