callchain.c 34.8 KB
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/*
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 * Copyright (C) 2009-2011, Frederic Weisbecker <fweisbec@gmail.com>
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 *
 * Handle the callchains from the stream in an ad-hoc radix tree and then
 * sort them in an rbtree.
 *
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 * Using a radix for code path provides a fast retrieval and factorizes
 * memory use. Also that lets us use the paths in a hierarchical graph view.
 *
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 */

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#include <inttypes.h>
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#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <errno.h>
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#include <math.h>
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#include "asm/bug.h"

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#include "hist.h"
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#include "util.h"
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#include "sort.h"
#include "machine.h"
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#include "callchain.h"
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#include "branch.h"
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#define CALLCHAIN_PARAM_DEFAULT			\
	.mode		= CHAIN_GRAPH_ABS,	\
	.min_percent	= 0.5,			\
	.order		= ORDER_CALLEE,		\
	.key		= CCKEY_FUNCTION,	\
	.value		= CCVAL_PERCENT,	\

struct callchain_param callchain_param = {
	CALLCHAIN_PARAM_DEFAULT
};

struct callchain_param callchain_param_default = {
	CALLCHAIN_PARAM_DEFAULT
};

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__thread struct callchain_cursor callchain_cursor;

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int parse_callchain_record_opt(const char *arg, struct callchain_param *param)
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{
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	return parse_callchain_record(arg, param);
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}

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static int parse_callchain_mode(const char *value)
{
	if (!strncmp(value, "graph", strlen(value))) {
		callchain_param.mode = CHAIN_GRAPH_ABS;
		return 0;
	}
	if (!strncmp(value, "flat", strlen(value))) {
		callchain_param.mode = CHAIN_FLAT;
		return 0;
	}
	if (!strncmp(value, "fractal", strlen(value))) {
		callchain_param.mode = CHAIN_GRAPH_REL;
		return 0;
	}
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	if (!strncmp(value, "folded", strlen(value))) {
		callchain_param.mode = CHAIN_FOLDED;
		return 0;
	}
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	return -1;
}

static int parse_callchain_order(const char *value)
{
	if (!strncmp(value, "caller", strlen(value))) {
		callchain_param.order = ORDER_CALLER;
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		callchain_param.order_set = true;
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		return 0;
	}
	if (!strncmp(value, "callee", strlen(value))) {
		callchain_param.order = ORDER_CALLEE;
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		callchain_param.order_set = true;
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		return 0;
	}
	return -1;
}

static int parse_callchain_sort_key(const char *value)
{
	if (!strncmp(value, "function", strlen(value))) {
		callchain_param.key = CCKEY_FUNCTION;
		return 0;
	}
	if (!strncmp(value, "address", strlen(value))) {
		callchain_param.key = CCKEY_ADDRESS;
		return 0;
	}
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	if (!strncmp(value, "srcline", strlen(value))) {
		callchain_param.key = CCKEY_SRCLINE;
		return 0;
	}
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	if (!strncmp(value, "branch", strlen(value))) {
		callchain_param.branch_callstack = 1;
		return 0;
	}
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	return -1;
}

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static int parse_callchain_value(const char *value)
{
	if (!strncmp(value, "percent", strlen(value))) {
		callchain_param.value = CCVAL_PERCENT;
		return 0;
	}
	if (!strncmp(value, "period", strlen(value))) {
		callchain_param.value = CCVAL_PERIOD;
		return 0;
	}
	if (!strncmp(value, "count", strlen(value))) {
		callchain_param.value = CCVAL_COUNT;
		return 0;
	}
	return -1;
}

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static int get_stack_size(const char *str, unsigned long *_size)
{
	char *endptr;
	unsigned long size;
	unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));

	size = strtoul(str, &endptr, 0);

	do {
		if (*endptr)
			break;

		size = round_up(size, sizeof(u64));
		if (!size || size > max_size)
			break;

		*_size = size;
		return 0;

	} while (0);

	pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
	       max_size, str);
	return -1;
}

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static int
__parse_callchain_report_opt(const char *arg, bool allow_record_opt)
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{
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	char *tok;
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	char *endptr, *saveptr = NULL;
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	bool minpcnt_set = false;
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	bool record_opt_set = false;
	bool try_stack_size = false;
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	callchain_param.enabled = true;
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	symbol_conf.use_callchain = true;

	if (!arg)
		return 0;

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	while ((tok = strtok_r((char *)arg, ",", &saveptr)) != NULL) {
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		if (!strncmp(tok, "none", strlen(tok))) {
			callchain_param.mode = CHAIN_NONE;
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			callchain_param.enabled = false;
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			symbol_conf.use_callchain = false;
			return 0;
		}

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		if (!parse_callchain_mode(tok) ||
		    !parse_callchain_order(tok) ||
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		    !parse_callchain_sort_key(tok) ||
		    !parse_callchain_value(tok)) {
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			/* parsing ok - move on to the next */
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			try_stack_size = false;
			goto next;
		} else if (allow_record_opt && !record_opt_set) {
			if (parse_callchain_record(tok, &callchain_param))
				goto try_numbers;

			/* assume that number followed by 'dwarf' is stack size */
			if (callchain_param.record_mode == CALLCHAIN_DWARF)
				try_stack_size = true;

			record_opt_set = true;
			goto next;
		}

try_numbers:
		if (try_stack_size) {
			unsigned long size = 0;

			if (get_stack_size(tok, &size) < 0)
				return -1;
			callchain_param.dump_size = size;
			try_stack_size = false;
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		} else if (!minpcnt_set) {
			/* try to get the min percent */
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			callchain_param.min_percent = strtod(tok, &endptr);
			if (tok == endptr)
				return -1;
			minpcnt_set = true;
		} else {
			/* try print limit at last */
			callchain_param.print_limit = strtoul(tok, &endptr, 0);
			if (tok == endptr)
				return -1;
		}
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next:
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		arg = NULL;
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	}

	if (callchain_register_param(&callchain_param) < 0) {
		pr_err("Can't register callchain params\n");
		return -1;
	}
	return 0;
}

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int parse_callchain_report_opt(const char *arg)
{
	return __parse_callchain_report_opt(arg, false);
}

int parse_callchain_top_opt(const char *arg)
{
	return __parse_callchain_report_opt(arg, true);
}

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int parse_callchain_record(const char *arg, struct callchain_param *param)
{
	char *tok, *name, *saveptr = NULL;
	char *buf;
	int ret = -1;

	/* We need buffer that we know we can write to. */
	buf = malloc(strlen(arg) + 1);
	if (!buf)
		return -ENOMEM;

	strcpy(buf, arg);

	tok = strtok_r((char *)buf, ",", &saveptr);
	name = tok ? : (char *)buf;

	do {
		/* Framepointer style */
		if (!strncmp(name, "fp", sizeof("fp"))) {
			if (!strtok_r(NULL, ",", &saveptr)) {
				param->record_mode = CALLCHAIN_FP;
				ret = 0;
			} else
				pr_err("callchain: No more arguments "
				       "needed for --call-graph fp\n");
			break;

		/* Dwarf style */
		} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
			const unsigned long default_stack_dump_size = 8192;

			ret = 0;
			param->record_mode = CALLCHAIN_DWARF;
			param->dump_size = default_stack_dump_size;

			tok = strtok_r(NULL, ",", &saveptr);
			if (tok) {
				unsigned long size = 0;

				ret = get_stack_size(tok, &size);
				param->dump_size = size;
			}
		} else if (!strncmp(name, "lbr", sizeof("lbr"))) {
			if (!strtok_r(NULL, ",", &saveptr)) {
				param->record_mode = CALLCHAIN_LBR;
				ret = 0;
			} else
				pr_err("callchain: No more arguments "
					"needed for --call-graph lbr\n");
			break;
		} else {
			pr_err("callchain: Unknown --call-graph option "
			       "value: %s\n", arg);
			break;
		}

	} while (0);

	free(buf);
	return ret;
}

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int perf_callchain_config(const char *var, const char *value)
{
	char *endptr;

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	if (!strstarts(var, "call-graph."))
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		return 0;
	var += sizeof("call-graph.") - 1;

	if (!strcmp(var, "record-mode"))
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		return parse_callchain_record_opt(value, &callchain_param);
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	if (!strcmp(var, "dump-size")) {
		unsigned long size = 0;
		int ret;

		ret = get_stack_size(value, &size);
		callchain_param.dump_size = size;

		return ret;
	}
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	if (!strcmp(var, "print-type")){
		int ret;
		ret = parse_callchain_mode(value);
		if (ret == -1)
			pr_err("Invalid callchain mode: %s\n", value);
		return ret;
	}
	if (!strcmp(var, "order")){
		int ret;
		ret = parse_callchain_order(value);
		if (ret == -1)
			pr_err("Invalid callchain order: %s\n", value);
		return ret;
	}
	if (!strcmp(var, "sort-key")){
		int ret;
		ret = parse_callchain_sort_key(value);
		if (ret == -1)
			pr_err("Invalid callchain sort key: %s\n", value);
		return ret;
	}
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	if (!strcmp(var, "threshold")) {
		callchain_param.min_percent = strtod(value, &endptr);
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		if (value == endptr) {
			pr_err("Invalid callchain threshold: %s\n", value);
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			return -1;
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		}
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	}
	if (!strcmp(var, "print-limit")) {
		callchain_param.print_limit = strtod(value, &endptr);
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		if (value == endptr) {
			pr_err("Invalid callchain print limit: %s\n", value);
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			return -1;
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		}
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	}

	return 0;
}

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static void
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rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
		    enum chain_mode mode)
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{
	struct rb_node **p = &root->rb_node;
	struct rb_node *parent = NULL;
	struct callchain_node *rnode;
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	u64 chain_cumul = callchain_cumul_hits(chain);
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	while (*p) {
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		u64 rnode_cumul;

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		parent = *p;
		rnode = rb_entry(parent, struct callchain_node, rb_node);
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		rnode_cumul = callchain_cumul_hits(rnode);
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		switch (mode) {
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		case CHAIN_FLAT:
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		case CHAIN_FOLDED:
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			if (rnode->hit < chain->hit)
				p = &(*p)->rb_left;
			else
				p = &(*p)->rb_right;
			break;
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		case CHAIN_GRAPH_ABS: /* Falldown */
		case CHAIN_GRAPH_REL:
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			if (rnode_cumul < chain_cumul)
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				p = &(*p)->rb_left;
			else
				p = &(*p)->rb_right;
			break;
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		case CHAIN_NONE:
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		default:
			break;
		}
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	}

	rb_link_node(&chain->rb_node, parent, p);
	rb_insert_color(&chain->rb_node, root);
}

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static void
__sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
		  u64 min_hit)
{
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	struct rb_node *n;
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	struct callchain_node *child;

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	n = rb_first(&node->rb_root_in);
	while (n) {
		child = rb_entry(n, struct callchain_node, rb_node_in);
		n = rb_next(n);

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		__sort_chain_flat(rb_root, child, min_hit);
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	}
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	if (node->hit && node->hit >= min_hit)
		rb_insert_callchain(rb_root, node, CHAIN_FLAT);
}

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/*
 * Once we get every callchains from the stream, we can now
 * sort them by hit
 */
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static void
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sort_chain_flat(struct rb_root *rb_root, struct callchain_root *root,
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		u64 min_hit, struct callchain_param *param __maybe_unused)
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{
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	*rb_root = RB_ROOT;
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	__sort_chain_flat(rb_root, &root->node, min_hit);
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}

static void __sort_chain_graph_abs(struct callchain_node *node,
				   u64 min_hit)
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{
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	struct rb_node *n;
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	struct callchain_node *child;

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	node->rb_root = RB_ROOT;
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	n = rb_first(&node->rb_root_in);

	while (n) {
		child = rb_entry(n, struct callchain_node, rb_node_in);
		n = rb_next(n);
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		__sort_chain_graph_abs(child, min_hit);
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		if (callchain_cumul_hits(child) >= min_hit)
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			rb_insert_callchain(&node->rb_root, child,
					    CHAIN_GRAPH_ABS);
	}
}

static void
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sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_root *chain_root,
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		     u64 min_hit, struct callchain_param *param __maybe_unused)
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{
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	__sort_chain_graph_abs(&chain_root->node, min_hit);
	rb_root->rb_node = chain_root->node.rb_root.rb_node;
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}

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static void __sort_chain_graph_rel(struct callchain_node *node,
				   double min_percent)
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{
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	struct rb_node *n;
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	struct callchain_node *child;
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	u64 min_hit;
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	node->rb_root = RB_ROOT;
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	min_hit = ceil(node->children_hit * min_percent);
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	n = rb_first(&node->rb_root_in);
	while (n) {
		child = rb_entry(n, struct callchain_node, rb_node_in);
		n = rb_next(n);

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		__sort_chain_graph_rel(child, min_percent);
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		if (callchain_cumul_hits(child) >= min_hit)
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			rb_insert_callchain(&node->rb_root, child,
					    CHAIN_GRAPH_REL);
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	}
}

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static void
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sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_root *chain_root,
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		     u64 min_hit __maybe_unused, struct callchain_param *param)
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{
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	__sort_chain_graph_rel(&chain_root->node, param->min_percent / 100.0);
	rb_root->rb_node = chain_root->node.rb_root.rb_node;
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}

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int callchain_register_param(struct callchain_param *param)
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{
	switch (param->mode) {
	case CHAIN_GRAPH_ABS:
		param->sort = sort_chain_graph_abs;
		break;
	case CHAIN_GRAPH_REL:
		param->sort = sort_chain_graph_rel;
		break;
	case CHAIN_FLAT:
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	case CHAIN_FOLDED:
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		param->sort = sort_chain_flat;
		break;
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	case CHAIN_NONE:
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	default:
		return -1;
	}
	return 0;
}

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/*
 * Create a child for a parent. If inherit_children, then the new child
 * will become the new parent of it's parent children
 */
static struct callchain_node *
create_child(struct callchain_node *parent, bool inherit_children)
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{
	struct callchain_node *new;

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	new = zalloc(sizeof(*new));
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	if (!new) {
		perror("not enough memory to create child for code path tree");
		return NULL;
	}
	new->parent = parent;
	INIT_LIST_HEAD(&new->val);
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	INIT_LIST_HEAD(&new->parent_val);
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	if (inherit_children) {
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		struct rb_node *n;
		struct callchain_node *child;

		new->rb_root_in = parent->rb_root_in;
		parent->rb_root_in = RB_ROOT;
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		n = rb_first(&new->rb_root_in);
		while (n) {
			child = rb_entry(n, struct callchain_node, rb_node_in);
			child->parent = new;
			n = rb_next(n);
		}
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		/* make it the first child */
		rb_link_node(&new->rb_node_in, NULL, &parent->rb_root_in.rb_node);
		rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
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	}
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	return new;
}

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/*
 * Fill the node with callchain values
 */
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static int
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fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
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{
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	struct callchain_cursor_node *cursor_node;

	node->val_nr = cursor->nr - cursor->pos;
	if (!node->val_nr)
		pr_warning("Warning: empty node in callchain tree\n");
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	cursor_node = callchain_cursor_current(cursor);

	while (cursor_node) {
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		struct callchain_list *call;

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		call = zalloc(sizeof(*call));
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		if (!call) {
			perror("not enough memory for the code path tree");
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			return -1;
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		}
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		call->ip = cursor_node->ip;
		call->ms.sym = cursor_node->sym;
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		call->ms.map = map__get(cursor_node->map);
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		call->srcline = cursor_node->srcline;
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		if (cursor_node->branch) {
			call->branch_count = 1;

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			if (cursor_node->branch_from) {
				/*
				 * branch_from is set with value somewhere else
				 * to imply it's "to" of a branch.
				 */
				call->brtype_stat.branch_to = true;

				if (cursor_node->branch_flags.predicted)
					call->predicted_count = 1;

				if (cursor_node->branch_flags.abort)
					call->abort_count = 1;

				branch_type_count(&call->brtype_stat,
						  &cursor_node->branch_flags,
						  cursor_node->branch_from,
						  cursor_node->ip);
			} else {
				/*
				 * It's "from" of a branch
				 */
				call->brtype_stat.branch_to = false;
				call->cycles_count =
					cursor_node->branch_flags.cycles;
				call->iter_count = cursor_node->nr_loop_iter;
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				call->iter_cycles = cursor_node->iter_cycles;
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			}
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		}

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		list_add_tail(&call->list, &node->val);
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		callchain_cursor_advance(cursor);
		cursor_node = callchain_cursor_current(cursor);
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	}
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	return 0;
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}

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static struct callchain_node *
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add_child(struct callchain_node *parent,
	  struct callchain_cursor *cursor,
	  u64 period)
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{
	struct callchain_node *new;

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	new = create_child(parent, false);
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	if (new == NULL)
		return NULL;

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	if (fill_node(new, cursor) < 0) {
		struct callchain_list *call, *tmp;

		list_for_each_entry_safe(call, tmp, &new->val, list) {
			list_del(&call->list);
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			map__zput(call->ms.map);
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			free(call);
		}
		free(new);
		return NULL;
	}
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	new->children_hit = 0;
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	new->hit = period;
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	new->children_count = 0;
	new->count = 1;
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	return new;
}

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enum match_result {
	MATCH_ERROR  = -1,
	MATCH_EQ,
	MATCH_LT,
	MATCH_GT,
};

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static enum match_result match_chain_strings(const char *left,
					     const char *right)
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{
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	enum match_result ret = MATCH_EQ;
	int cmp;

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	if (left && right)
		cmp = strcmp(left, right);
	else if (!left && right)
		cmp = 1;
	else if (left && !right)
		cmp = -1;
	else
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		return MATCH_ERROR;
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	if (cmp != 0)
		ret = cmp < 0 ? MATCH_LT : MATCH_GT;

	return ret;
}

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static enum match_result match_chain(struct callchain_cursor_node *node,
				     struct callchain_list *cnode)
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{
	struct symbol *sym = node->sym;
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	u64 left, right;
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	struct dso *left_dso = NULL;
	struct dso *right_dso = NULL;
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	if (callchain_param.key == CCKEY_SRCLINE) {
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		enum match_result match = match_chain_strings(cnode->srcline,
							      node->srcline);

		/* if no srcline is available, fallback to symbol name */
		if (match == MATCH_ERROR && cnode->ms.sym && node->sym)
			match = match_chain_strings(cnode->ms.sym->name,
						    node->sym->name);
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		if (match != MATCH_ERROR)
			return match;
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		/* otherwise fall-back to IP-based comparison below */
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	}

	if (cnode->ms.sym && sym && callchain_param.key == CCKEY_FUNCTION) {
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		left = cnode->ms.sym->start;
		right = sym->start;
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		left_dso = cnode->ms.map->dso;
		right_dso = node->map->dso;
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	} else {
		left = cnode->ip;
		right = node->ip;
	}

702
	if (left == right && left_dso == right_dso) {
703 704 705
		if (node->branch) {
			cnode->branch_count++;

706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729
			if (node->branch_from) {
				/*
				 * It's "to" of a branch
				 */
				cnode->brtype_stat.branch_to = true;

				if (node->branch_flags.predicted)
					cnode->predicted_count++;

				if (node->branch_flags.abort)
					cnode->abort_count++;

				branch_type_count(&cnode->brtype_stat,
						  &node->branch_flags,
						  node->branch_from,
						  node->ip);
			} else {
				/*
				 * It's "from" of a branch
				 */
				cnode->brtype_stat.branch_to = false;
				cnode->cycles_count +=
					node->branch_flags.cycles;
				cnode->iter_count += node->nr_loop_iter;
730
				cnode->iter_cycles += node->iter_cycles;
731
			}
732 733
		}

734
		return MATCH_EQ;
735
	}
736 737

	return left > right ? MATCH_GT : MATCH_LT;
738 739
}

740 741 742 743 744
/*
 * Split the parent in two parts (a new child is created) and
 * give a part of its callchain to the created child.
 * Then create another child to host the given callchain of new branch
 */
745
static int
746 747 748 749
split_add_child(struct callchain_node *parent,
		struct callchain_cursor *cursor,
		struct callchain_list *to_split,
		u64 idx_parents, u64 idx_local, u64 period)
750 751
{
	struct callchain_node *new;
752
	struct list_head *old_tail;
753
	unsigned int idx_total = idx_parents + idx_local;
754 755

	/* split */
756
	new = create_child(parent, true);
757 758
	if (new == NULL)
		return -1;
759 760 761 762 763 764 765 766

	/* split the callchain and move a part to the new child */
	old_tail = parent->val.prev;
	list_del_range(&to_split->list, old_tail);
	new->val.next = &to_split->list;
	new->val.prev = old_tail;
	to_split->list.prev = &new->val;
	old_tail->next = &new->val;
767

768 769
	/* split the hits */
	new->hit = parent->hit;
770
	new->children_hit = parent->children_hit;
771
	parent->children_hit = callchain_cumul_hits(new);
772 773
	new->val_nr = parent->val_nr - idx_local;
	parent->val_nr = idx_local;
774 775 776
	new->count = parent->count;
	new->children_count = parent->children_count;
	parent->children_count = callchain_cumul_counts(new);
777 778

	/* create a new child for the new branch if any */
779
	if (idx_total < cursor->nr) {
780 781 782 783 784
		struct callchain_node *first;
		struct callchain_list *cnode;
		struct callchain_cursor_node *node;
		struct rb_node *p, **pp;

785
		parent->hit = 0;
786
		parent->children_hit += period;
787 788
		parent->count = 0;
		parent->children_count += 1;
789 790 791

		node = callchain_cursor_current(cursor);
		new = add_child(parent, cursor, period);
792
		if (new == NULL)
793
			return -1;
794 795 796 797 798 799 800 801 802 803

		/*
		 * This is second child since we moved parent's children
		 * to new (first) child above.
		 */
		p = parent->rb_root_in.rb_node;
		first = rb_entry(p, struct callchain_node, rb_node_in);
		cnode = list_first_entry(&first->val, struct callchain_list,
					 list);

804
		if (match_chain(node, cnode) == MATCH_LT)
805 806 807 808 809 810
			pp = &p->rb_left;
		else
			pp = &p->rb_right;

		rb_link_node(&new->rb_node_in, p, pp);
		rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
811
	} else {
812
		parent->hit = period;
813
		parent->count = 1;
814
	}
815
	return 0;
816 817
}

818
static enum match_result
819 820 821
append_chain(struct callchain_node *root,
	     struct callchain_cursor *cursor,
	     u64 period);
822

823
static int
824 825 826
append_chain_children(struct callchain_node *root,
		      struct callchain_cursor *cursor,
		      u64 period)
827 828
{
	struct callchain_node *rnode;
829 830 831 832 833 834
	struct callchain_cursor_node *node;
	struct rb_node **p = &root->rb_root_in.rb_node;
	struct rb_node *parent = NULL;

	node = callchain_cursor_current(cursor);
	if (!node)
835
		return -1;
836 837

	/* lookup in childrens */
838
	while (*p) {
839
		enum match_result ret;
840

841 842 843
		parent = *p;
		rnode = rb_entry(parent, struct callchain_node, rb_node_in);

844 845
		/* If at least first entry matches, rely to children */
		ret = append_chain(rnode, cursor, period);
846
		if (ret == MATCH_EQ)
847
			goto inc_children_hit;
848 849
		if (ret == MATCH_ERROR)
			return -1;
850

851
		if (ret == MATCH_LT)
852 853 854
			p = &parent->rb_left;
		else
			p = &parent->rb_right;
855
	}
856
	/* nothing in children, add to the current node */
857
	rnode = add_child(root, cursor, period);
858
	if (rnode == NULL)
859
		return -1;
860

861 862
	rb_link_node(&rnode->rb_node_in, parent, p);
	rb_insert_color(&rnode->rb_node_in, &root->rb_root_in);
863

864
inc_children_hit:
865
	root->children_hit += period;
866
	root->children_count++;
867
	return 0;
868 869
}

870
static enum match_result
871 872 873
append_chain(struct callchain_node *root,
	     struct callchain_cursor *cursor,
	     u64 period)
874 875
{
	struct callchain_list *cnode;
876
	u64 start = cursor->pos;
877
	bool found = false;
878
	u64 matches;
879
	enum match_result cmp = MATCH_ERROR;
880

881 882 883
	/*
	 * Lookup in the current node
	 * If we have a symbol, then compare the start to match
884 885
	 * anywhere inside a function, unless function
	 * mode is disabled.
886
	 */
887
	list_for_each_entry(cnode, &root->val, list) {
888
		struct callchain_cursor_node *node;
889

890 891
		node = callchain_cursor_current(cursor);
		if (!node)
892
			break;
893

894
		cmp = match_chain(node, cnode);
895
		if (cmp != MATCH_EQ)
896
			break;
897

898
		found = true;
899 900

		callchain_cursor_advance(cursor);
901 902
	}

903
	/* matches not, relay no the parent */
904
	if (!found) {
905
		WARN_ONCE(cmp == MATCH_ERROR, "Chain comparison error\n");
906
		return cmp;
907 908 909
	}

	matches = cursor->pos - start;
910 911

	/* we match only a part of the node. Split it and add the new chain */
912
	if (matches < root->val_nr) {
913 914 915 916
		if (split_add_child(root, cursor, cnode, start, matches,
				    period) < 0)
			return MATCH_ERROR;

917
		return MATCH_EQ;
918 919 920
	}

	/* we match 100% of the path, increment the hit */
921
	if (matches == root->val_nr && cursor->pos == cursor->nr) {
922
		root->hit += period;
923
		root->count++;
924
		return MATCH_EQ;
925 926
	}

927
	/* We match the node and still have a part remaining */
928 929
	if (append_chain_children(root, cursor, period) < 0)
		return MATCH_ERROR;
930

931
	return MATCH_EQ;
932 933
}

934 935 936
int callchain_append(struct callchain_root *root,
		     struct callchain_cursor *cursor,
		     u64 period)
937
{
938
	if (!cursor->nr)
939 940
		return 0;

941
	callchain_cursor_commit(cursor);
942

943 944
	if (append_chain_children(&root->node, cursor, period) < 0)
		return -1;
945

946 947
	if (cursor->nr > root->max_depth)
		root->max_depth = cursor->nr;
948 949

	return 0;
950
}
951 952

static int
953 954
merge_chain_branch(struct callchain_cursor *cursor,
		   struct callchain_node *dst, struct callchain_node *src)
955
{
956
	struct callchain_cursor_node **old_last = cursor->last;
957
	struct callchain_node *child;
958
	struct callchain_list *list, *next_list;
959
	struct rb_node *n;
960
	int old_pos = cursor->nr;
961 962 963
	int err = 0;

	list_for_each_entry_safe(list, next_list, &src->val, list) {
964
		callchain_cursor_append(cursor, list->ip,
965
					list->ms.map, list->ms.sym,
966
					false, NULL, 0, 0, 0, list->srcline);
967
		list_del(&list->list);
968
		map__zput(list->ms.map);
969 970 971
		free(list);
	}

972 973
	if (src->hit) {
		callchain_cursor_commit(cursor);
974 975
		if (append_chain_children(dst, cursor, src->hit) < 0)
			return -1;
976
	}
977

978 979 980 981 982 983
	n = rb_first(&src->rb_root_in);
	while (n) {
		child = container_of(n, struct callchain_node, rb_node_in);
		n = rb_next(n);
		rb_erase(&child->rb_node_in, &src->rb_root_in);

984
		err = merge_chain_branch(cursor, dst, child);
985 986 987 988 989 990
		if (err)
			break;

		free(child);
	}

991 992
	cursor->nr = old_pos;
	cursor->last = old_last;
993 994 995 996

	return err;
}

997 998 999 1000 1001 1002 1003
int callchain_merge(struct callchain_cursor *cursor,
		    struct callchain_root *dst, struct callchain_root *src)
{
	return merge_chain_branch(cursor, &dst->node, &src->node);
}

int callchain_cursor_append(struct callchain_cursor *cursor,
1004 1005
			    u64 ip, struct map *map, struct symbol *sym,
			    bool branch, struct branch_flags *flags,
1006 1007
			    int nr_loop_iter, u64 iter_cycles, u64 branch_from,
			    const char *srcline)
1008
{
1009
	struct callchain_cursor_node *node = *cursor->last;
1010

1011
	if (!node) {
1012
		node = calloc(1, sizeof(*node));
1013 1014
		if (!node)
			return -ENOMEM;
1015

1016 1017
		*cursor->last = node;
	}
1018

1019
	node->ip = ip;
1020 1021
	map__zput(node->map);
	node->map = map__get(map);
1022
	node->sym = sym;
1023 1024
	node->branch = branch;
	node->nr_loop_iter = nr_loop_iter;
1025
	node->iter_cycles = iter_cycles;
1026
	node->srcline = srcline;
1027 1028 1029 1030

	if (flags)
		memcpy(&node->branch_flags, flags,
			sizeof(struct branch_flags));
1031

1032
	node->branch_from = branch_from;
1033
	cursor->nr++;
1034

1035 1036 1037
	cursor->last = &node->next;

	return 0;
1038
}
1039

1040 1041
int sample__resolve_callchain(struct perf_sample *sample,
			      struct callchain_cursor *cursor, struct symbol **parent,
1042 1043 1044
			      struct perf_evsel *evsel, struct addr_location *al,
			      int max_stack)
{
1045
	if (sample->callchain == NULL && !symbol_conf.show_branchflag_count)
1046 1047
		return 0;

1048
	if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain ||
1049
	    perf_hpp_list.parent || symbol_conf.show_branchflag_count) {
1050
		return thread__resolve_callchain(al->thread, cursor, evsel, sample,
1051
						 parent, al, max_stack);
1052 1053 1054 1055 1056 1057
	}
	return 0;
}

int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample)
{
1058 1059
	if ((!symbol_conf.use_callchain || sample->callchain == NULL) &&
		!symbol_conf.show_branchflag_count)
1060 1061 1062
		return 0;
	return callchain_append(he->callchain, &callchain_cursor, sample->period);
}
1063 1064 1065 1066 1067 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 1099 1100 1101 1102 1103 1104

int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
			bool hide_unresolved)
{
	al->map = node->map;
	al->sym = node->sym;
	if (node->map)
		al->addr = node->map->map_ip(node->map, node->ip);
	else
		al->addr = node->ip;

	if (al->sym == NULL) {
		if (hide_unresolved)
			return 0;
		if (al->map == NULL)
			goto out;
	}

	if (al->map->groups == &al->machine->kmaps) {
		if (machine__is_host(al->machine)) {
			al->cpumode = PERF_RECORD_MISC_KERNEL;
			al->level = 'k';
		} else {
			al->cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
			al->level = 'g';
		}
	} else {
		if (machine__is_host(al->machine)) {
			al->cpumode = PERF_RECORD_MISC_USER;
			al->level = '.';
		} else if (perf_guest) {
			al->cpumode = PERF_RECORD_MISC_GUEST_USER;
			al->level = 'u';
		} else {
			al->cpumode = PERF_RECORD_MISC_HYPERVISOR;
			al->level = 'H';
		}
	}

out:
	return 1;
}
1105 1106 1107 1108

char *callchain_list__sym_name(struct callchain_list *cl,
			       char *bf, size_t bfsize, bool show_dso)
{
1109 1110
	bool show_addr = callchain_param.key == CCKEY_ADDRESS;
	bool show_srcline = show_addr || callchain_param.key == CCKEY_SRCLINE;
1111 1112 1113
	int printed;

	if (cl->ms.sym) {
1114
		if (show_srcline && cl->srcline)
1115 1116 1117 1118
			printed = scnprintf(bf, bfsize, "%s %s",
					cl->ms.sym->name, cl->srcline);
		else
			printed = scnprintf(bf, bfsize, "%s", cl->ms.sym->name);
1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129
	} else
		printed = scnprintf(bf, bfsize, "%#" PRIx64, cl->ip);

	if (show_dso)
		scnprintf(bf + printed, bfsize - printed, " %s",
			  cl->ms.map ?
			  cl->ms.map->dso->short_name :
			  "unknown");

	return bf;
}
1130

1131 1132 1133 1134 1135
char *callchain_node__scnprintf_value(struct callchain_node *node,
				      char *bf, size_t bfsize, u64 total)
{
	double percent = 0.0;
	u64 period = callchain_cumul_hits(node);
1136
	unsigned count = callchain_cumul_counts(node);
1137

1138
	if (callchain_param.mode == CHAIN_FOLDED) {
1139
		period = node->hit;
1140 1141
		count = node->count;
	}
1142

1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156
	switch (callchain_param.value) {
	case CCVAL_PERIOD:
		scnprintf(bf, bfsize, "%"PRIu64, period);
		break;
	case CCVAL_COUNT:
		scnprintf(bf, bfsize, "%u", count);
		break;
	case CCVAL_PERCENT:
	default:
		if (total)
			percent = period * 100.0 / total;
		scnprintf(bf, bfsize, "%.2f%%", percent);
		break;
	}
1157 1158 1159 1160 1161 1162 1163 1164
	return bf;
}

int callchain_node__fprintf_value(struct callchain_node *node,
				 FILE *fp, u64 total)
{
	double percent = 0.0;
	u64 period = callchain_cumul_hits(node);
1165
	unsigned count = callchain_cumul_counts(node);
1166

1167
	if (callchain_param.mode == CHAIN_FOLDED) {
1168
		period = node->hit;
1169 1170
		count = node->count;
	}
1171

1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183
	switch (callchain_param.value) {
	case CCVAL_PERIOD:
		return fprintf(fp, "%"PRIu64, period);
	case CCVAL_COUNT:
		return fprintf(fp, "%u", count);
	case CCVAL_PERCENT:
	default:
		if (total)
			percent = period * 100.0 / total;
		return percent_color_fprintf(fp, "%.2f%%", percent);
	}
	return 0;
1184 1185
}

1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256
static void callchain_counts_value(struct callchain_node *node,
				   u64 *branch_count, u64 *predicted_count,
				   u64 *abort_count, u64 *cycles_count)
{
	struct callchain_list *clist;

	list_for_each_entry(clist, &node->val, list) {
		if (branch_count)
			*branch_count += clist->branch_count;

		if (predicted_count)
			*predicted_count += clist->predicted_count;

		if (abort_count)
			*abort_count += clist->abort_count;

		if (cycles_count)
			*cycles_count += clist->cycles_count;
	}
}

static int callchain_node_branch_counts_cumul(struct callchain_node *node,
					      u64 *branch_count,
					      u64 *predicted_count,
					      u64 *abort_count,
					      u64 *cycles_count)
{
	struct callchain_node *child;
	struct rb_node *n;

	n = rb_first(&node->rb_root_in);
	while (n) {
		child = rb_entry(n, struct callchain_node, rb_node_in);
		n = rb_next(n);

		callchain_node_branch_counts_cumul(child, branch_count,
						   predicted_count,
						   abort_count,
						   cycles_count);

		callchain_counts_value(child, branch_count,
				       predicted_count, abort_count,
				       cycles_count);
	}

	return 0;
}

int callchain_branch_counts(struct callchain_root *root,
			    u64 *branch_count, u64 *predicted_count,
			    u64 *abort_count, u64 *cycles_count)
{
	if (branch_count)
		*branch_count = 0;

	if (predicted_count)
		*predicted_count = 0;

	if (abort_count)
		*abort_count = 0;

	if (cycles_count)
		*cycles_count = 0;

	return callchain_node_branch_counts_cumul(&root->node,
						  branch_count,
						  predicted_count,
						  abort_count,
						  cycles_count);
}

1257 1258 1259 1260 1261 1262 1263 1264 1265
static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int bfsize)
{
	int printed;

	printed = scnprintf(bf, bfsize, "%s%s:%" PRId64 "", (idx) ? " " : " (", str, value);

	return printed;
}

1266 1267
static int count_float_printf(int idx, const char *str, float value,
			      char *bf, int bfsize, float threshold)
1268 1269 1270
{
	int printed;

1271 1272 1273
	if (threshold != 0.0 && value < threshold)
		return 0;

1274 1275 1276 1277 1278
	printed = scnprintf(bf, bfsize, "%s%s:%.1f%%", (idx) ? " " : " (", str, value);

	return printed;
}

1279 1280 1281 1282
static int branch_to_str(char *bf, int bfsize,
			 u64 branch_count, u64 predicted_count,
			 u64 abort_count,
			 struct branch_type_stat *brtype_stat)
1283
{
1284
	int printed, i = 0;
1285

1286 1287 1288 1289
	printed = branch_type_str(brtype_stat, bf, bfsize);
	if (printed)
		i++;

1290 1291 1292
	if (predicted_count < branch_count) {
		printed += count_float_printf(i++, "predicted",
				predicted_count * 100.0 / branch_count,
1293
				bf + printed, bfsize - printed, 0.0);
1294
	}
1295

1296 1297 1298
	if (abort_count) {
		printed += count_float_printf(i++, "abort",
				abort_count * 100.0 / branch_count,
1299
				bf + printed, bfsize - printed, 0.1);
1300
	}
1301

1302 1303 1304 1305 1306 1307 1308 1309 1310
	if (i)
		printed += scnprintf(bf + printed, bfsize - printed, ")");

	return printed;
}

static int branch_from_str(char *bf, int bfsize,
			   u64 branch_count,
			   u64 cycles_count, u64 iter_count,
1311
			   u64 iter_cycles)
1312 1313 1314 1315
{
	int printed = 0, i = 0;
	u64 cycles;

1316 1317 1318 1319 1320
	cycles = cycles_count / branch_count;
	if (cycles) {
		printed += count_pri64_printf(i++, "cycles",
				cycles,
				bf + printed, bfsize - printed);
1321 1322
	}

1323 1324 1325 1326 1327 1328 1329
	if (iter_count) {
		printed += count_pri64_printf(i++, "iter",
				iter_count,
				bf + printed, bfsize - printed);

		printed += count_pri64_printf(i++, "avg_cycles",
				iter_cycles / iter_count,
1330
				bf + printed, bfsize - printed);
1331
	}
1332

1333
	if (i)
1334
		printed += scnprintf(bf + printed, bfsize - printed, ")");
1335

1336 1337 1338 1339 1340 1341
	return printed;
}

static int counts_str_build(char *bf, int bfsize,
			     u64 branch_count, u64 predicted_count,
			     u64 abort_count, u64 cycles_count,
1342
			     u64 iter_count, u64 iter_cycles,
1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354
			     struct branch_type_stat *brtype_stat)
{
	int printed;

	if (branch_count == 0)
		return scnprintf(bf, bfsize, " (calltrace)");

	if (brtype_stat->branch_to) {
		printed = branch_to_str(bf, bfsize, branch_count,
				predicted_count, abort_count, brtype_stat);
	} else {
		printed = branch_from_str(bf, bfsize, branch_count,
1355
				cycles_count, iter_count, iter_cycles);
1356 1357 1358 1359 1360 1361
	}

	if (!printed)
		bf[0] = 0;

	return printed;
1362 1363 1364 1365 1366
}

static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
				   u64 branch_count, u64 predicted_count,
				   u64 abort_count, u64 cycles_count,
1367
				   u64 iter_count, u64 iter_cycles,
1368
				   struct branch_type_stat *brtype_stat)
1369
{
1370
	char str[256];
1371 1372 1373

	counts_str_build(str, sizeof(str), branch_count,
			 predicted_count, abort_count, cycles_count,
1374
			 iter_count, iter_cycles, brtype_stat);
1375 1376

	if (fp)
1377
		return fprintf(fp, "%s", str);
1378

1379
	return scnprintf(bf, bfsize, "%s", str);
1380 1381
}

1382
int callchain_list_counts__printf_value(struct callchain_list *clist,
1383 1384 1385 1386
					FILE *fp, char *bf, int bfsize)
{
	u64 branch_count, predicted_count;
	u64 abort_count, cycles_count;
1387
	u64 iter_count, iter_cycles;
1388 1389 1390 1391 1392

	branch_count = clist->branch_count;
	predicted_count = clist->predicted_count;
	abort_count = clist->abort_count;
	cycles_count = clist->cycles_count;
1393 1394
	iter_count = clist->iter_count;
	iter_cycles = clist->iter_cycles;
1395 1396 1397

	return callchain_counts_printf(fp, bf, bfsize, branch_count,
				       predicted_count, abort_count,
1398
				       cycles_count, iter_count, iter_cycles,
1399
				       &clist->brtype_stat);
1400 1401
}

1402 1403 1404 1405 1406 1407
static void free_callchain_node(struct callchain_node *node)
{
	struct callchain_list *list, *tmp;
	struct callchain_node *child;
	struct rb_node *n;

1408 1409
	list_for_each_entry_safe(list, tmp, &node->parent_val, list) {
		list_del(&list->list);
1410
		map__zput(list->ms.map);
1411 1412 1413
		free(list);
	}

1414 1415
	list_for_each_entry_safe(list, tmp, &node->val, list) {
		list_del(&list->list);
1416
		map__zput(list->ms.map);
1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437
		free(list);
	}

	n = rb_first(&node->rb_root_in);
	while (n) {
		child = container_of(n, struct callchain_node, rb_node_in);
		n = rb_next(n);
		rb_erase(&child->rb_node_in, &node->rb_root_in);

		free_callchain_node(child);
		free(child);
	}
}

void free_callchain(struct callchain_root *root)
{
	if (!symbol_conf.use_callchain)
		return;

	free_callchain_node(&root->node);
}
1438

1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466
static u64 decay_callchain_node(struct callchain_node *node)
{
	struct callchain_node *child;
	struct rb_node *n;
	u64 child_hits = 0;

	n = rb_first(&node->rb_root_in);
	while (n) {
		child = container_of(n, struct callchain_node, rb_node_in);

		child_hits += decay_callchain_node(child);
		n = rb_next(n);
	}

	node->hit = (node->hit * 7) / 8;
	node->children_hit = child_hits;

	return node->hit;
}

void decay_callchain(struct callchain_root *root)
{
	if (!symbol_conf.use_callchain)
		return;

	decay_callchain_node(&root->node);
}

1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479
int callchain_node__make_parent_list(struct callchain_node *node)
{
	struct callchain_node *parent = node->parent;
	struct callchain_list *chain, *new;
	LIST_HEAD(head);

	while (parent) {
		list_for_each_entry_reverse(chain, &parent->val, list) {
			new = malloc(sizeof(*new));
			if (new == NULL)
				goto out;
			*new = *chain;
			new->has_children = false;
1480
			map__get(new->ms.map);
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500
			list_add_tail(&new->list, &head);
		}
		parent = parent->parent;
	}

	list_for_each_entry_safe_reverse(chain, new, &head, list)
		list_move_tail(&chain->list, &node->parent_val);

	if (!list_empty(&node->parent_val)) {
		chain = list_first_entry(&node->parent_val, struct callchain_list, list);
		chain->has_children = rb_prev(&node->rb_node) || rb_next(&node->rb_node);

		chain = list_first_entry(&node->val, struct callchain_list, list);
		chain->has_children = false;
	}
	return 0;

out:
	list_for_each_entry_safe(chain, new, &head, list) {
		list_del(&chain->list);
1501
		map__zput(chain->ms.map);
1502 1503 1504 1505
		free(chain);
	}
	return -ENOMEM;
}
1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523

int callchain_cursor__copy(struct callchain_cursor *dst,
			   struct callchain_cursor *src)
{
	int rc = 0;

	callchain_cursor_reset(dst);
	callchain_cursor_commit(src);

	while (true) {
		struct callchain_cursor_node *node;

		node = callchain_cursor_current(src);
		if (node == NULL)
			break;

		rc = callchain_cursor_append(dst, node->ip, node->map, node->sym,
					     node->branch, &node->branch_flags,
1524 1525
					     node->nr_loop_iter,
					     node->iter_cycles,
1526
					     node->branch_from, node->srcline);
1527 1528 1529 1530 1531 1532 1533 1534
		if (rc)
			break;

		callchain_cursor_advance(src);
	}

	return rc;
}