xref: /openbmc/linux/tools/perf/util/callchain.c (revision faffb083)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2009-2011, Frederic Weisbecker <fweisbec@gmail.com>
4  *
5  * Handle the callchains from the stream in an ad-hoc radix tree and then
6  * sort them in an rbtree.
7  *
8  * Using a radix for code path provides a fast retrieval and factorizes
9  * memory use. Also that lets us use the paths in a hierarchical graph view.
10  *
11  */
12 
13 #include <inttypes.h>
14 #include <stdlib.h>
15 #include <stdio.h>
16 #include <stdbool.h>
17 #include <errno.h>
18 #include <math.h>
19 #include <linux/string.h>
20 #include <linux/zalloc.h>
21 
22 #include "asm/bug.h"
23 
24 #include "debug.h"
25 #include "dso.h"
26 #include "event.h"
27 #include "hist.h"
28 #include "sort.h"
29 #include "machine.h"
30 #include "map.h"
31 #include "callchain.h"
32 #include "branch.h"
33 #include "symbol.h"
34 #include "util.h"
35 #include "../perf.h"
36 
37 #define CALLCHAIN_PARAM_DEFAULT			\
38 	.mode		= CHAIN_GRAPH_ABS,	\
39 	.min_percent	= 0.5,			\
40 	.order		= ORDER_CALLEE,		\
41 	.key		= CCKEY_FUNCTION,	\
42 	.value		= CCVAL_PERCENT,	\
43 
44 struct callchain_param callchain_param = {
45 	CALLCHAIN_PARAM_DEFAULT
46 };
47 
48 /*
49  * Are there any events usind DWARF callchains?
50  *
51  * I.e.
52  *
53  * -e cycles/call-graph=dwarf/
54  */
55 bool dwarf_callchain_users;
56 
57 struct callchain_param callchain_param_default = {
58 	CALLCHAIN_PARAM_DEFAULT
59 };
60 
61 __thread struct callchain_cursor callchain_cursor;
62 
63 int parse_callchain_record_opt(const char *arg, struct callchain_param *param)
64 {
65 	return parse_callchain_record(arg, param);
66 }
67 
68 static int parse_callchain_mode(const char *value)
69 {
70 	if (!strncmp(value, "graph", strlen(value))) {
71 		callchain_param.mode = CHAIN_GRAPH_ABS;
72 		return 0;
73 	}
74 	if (!strncmp(value, "flat", strlen(value))) {
75 		callchain_param.mode = CHAIN_FLAT;
76 		return 0;
77 	}
78 	if (!strncmp(value, "fractal", strlen(value))) {
79 		callchain_param.mode = CHAIN_GRAPH_REL;
80 		return 0;
81 	}
82 	if (!strncmp(value, "folded", strlen(value))) {
83 		callchain_param.mode = CHAIN_FOLDED;
84 		return 0;
85 	}
86 	return -1;
87 }
88 
89 static int parse_callchain_order(const char *value)
90 {
91 	if (!strncmp(value, "caller", strlen(value))) {
92 		callchain_param.order = ORDER_CALLER;
93 		callchain_param.order_set = true;
94 		return 0;
95 	}
96 	if (!strncmp(value, "callee", strlen(value))) {
97 		callchain_param.order = ORDER_CALLEE;
98 		callchain_param.order_set = true;
99 		return 0;
100 	}
101 	return -1;
102 }
103 
104 static int parse_callchain_sort_key(const char *value)
105 {
106 	if (!strncmp(value, "function", strlen(value))) {
107 		callchain_param.key = CCKEY_FUNCTION;
108 		return 0;
109 	}
110 	if (!strncmp(value, "address", strlen(value))) {
111 		callchain_param.key = CCKEY_ADDRESS;
112 		return 0;
113 	}
114 	if (!strncmp(value, "srcline", strlen(value))) {
115 		callchain_param.key = CCKEY_SRCLINE;
116 		return 0;
117 	}
118 	if (!strncmp(value, "branch", strlen(value))) {
119 		callchain_param.branch_callstack = 1;
120 		return 0;
121 	}
122 	return -1;
123 }
124 
125 static int parse_callchain_value(const char *value)
126 {
127 	if (!strncmp(value, "percent", strlen(value))) {
128 		callchain_param.value = CCVAL_PERCENT;
129 		return 0;
130 	}
131 	if (!strncmp(value, "period", strlen(value))) {
132 		callchain_param.value = CCVAL_PERIOD;
133 		return 0;
134 	}
135 	if (!strncmp(value, "count", strlen(value))) {
136 		callchain_param.value = CCVAL_COUNT;
137 		return 0;
138 	}
139 	return -1;
140 }
141 
142 static int get_stack_size(const char *str, unsigned long *_size)
143 {
144 	char *endptr;
145 	unsigned long size;
146 	unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
147 
148 	size = strtoul(str, &endptr, 0);
149 
150 	do {
151 		if (*endptr)
152 			break;
153 
154 		size = round_up(size, sizeof(u64));
155 		if (!size || size > max_size)
156 			break;
157 
158 		*_size = size;
159 		return 0;
160 
161 	} while (0);
162 
163 	pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
164 	       max_size, str);
165 	return -1;
166 }
167 
168 static int
169 __parse_callchain_report_opt(const char *arg, bool allow_record_opt)
170 {
171 	char *tok;
172 	char *endptr, *saveptr = NULL;
173 	bool minpcnt_set = false;
174 	bool record_opt_set = false;
175 	bool try_stack_size = false;
176 
177 	callchain_param.enabled = true;
178 	symbol_conf.use_callchain = true;
179 
180 	if (!arg)
181 		return 0;
182 
183 	while ((tok = strtok_r((char *)arg, ",", &saveptr)) != NULL) {
184 		if (!strncmp(tok, "none", strlen(tok))) {
185 			callchain_param.mode = CHAIN_NONE;
186 			callchain_param.enabled = false;
187 			symbol_conf.use_callchain = false;
188 			return 0;
189 		}
190 
191 		if (!parse_callchain_mode(tok) ||
192 		    !parse_callchain_order(tok) ||
193 		    !parse_callchain_sort_key(tok) ||
194 		    !parse_callchain_value(tok)) {
195 			/* parsing ok - move on to the next */
196 			try_stack_size = false;
197 			goto next;
198 		} else if (allow_record_opt && !record_opt_set) {
199 			if (parse_callchain_record(tok, &callchain_param))
200 				goto try_numbers;
201 
202 			/* assume that number followed by 'dwarf' is stack size */
203 			if (callchain_param.record_mode == CALLCHAIN_DWARF)
204 				try_stack_size = true;
205 
206 			record_opt_set = true;
207 			goto next;
208 		}
209 
210 try_numbers:
211 		if (try_stack_size) {
212 			unsigned long size = 0;
213 
214 			if (get_stack_size(tok, &size) < 0)
215 				return -1;
216 			callchain_param.dump_size = size;
217 			try_stack_size = false;
218 		} else if (!minpcnt_set) {
219 			/* try to get the min percent */
220 			callchain_param.min_percent = strtod(tok, &endptr);
221 			if (tok == endptr)
222 				return -1;
223 			minpcnt_set = true;
224 		} else {
225 			/* try print limit at last */
226 			callchain_param.print_limit = strtoul(tok, &endptr, 0);
227 			if (tok == endptr)
228 				return -1;
229 		}
230 next:
231 		arg = NULL;
232 	}
233 
234 	if (callchain_register_param(&callchain_param) < 0) {
235 		pr_err("Can't register callchain params\n");
236 		return -1;
237 	}
238 	return 0;
239 }
240 
241 int parse_callchain_report_opt(const char *arg)
242 {
243 	return __parse_callchain_report_opt(arg, false);
244 }
245 
246 int parse_callchain_top_opt(const char *arg)
247 {
248 	return __parse_callchain_report_opt(arg, true);
249 }
250 
251 int parse_callchain_record(const char *arg, struct callchain_param *param)
252 {
253 	char *tok, *name, *saveptr = NULL;
254 	char *buf;
255 	int ret = -1;
256 
257 	/* We need buffer that we know we can write to. */
258 	buf = malloc(strlen(arg) + 1);
259 	if (!buf)
260 		return -ENOMEM;
261 
262 	strcpy(buf, arg);
263 
264 	tok = strtok_r((char *)buf, ",", &saveptr);
265 	name = tok ? : (char *)buf;
266 
267 	do {
268 		/* Framepointer style */
269 		if (!strncmp(name, "fp", sizeof("fp"))) {
270 			ret = 0;
271 			param->record_mode = CALLCHAIN_FP;
272 
273 			tok = strtok_r(NULL, ",", &saveptr);
274 			if (tok) {
275 				unsigned long size;
276 
277 				size = strtoul(tok, &name, 0);
278 				if (size < (unsigned) sysctl__max_stack())
279 					param->max_stack = size;
280 			}
281 			break;
282 
283 		/* Dwarf style */
284 		} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
285 			const unsigned long default_stack_dump_size = 8192;
286 
287 			ret = 0;
288 			param->record_mode = CALLCHAIN_DWARF;
289 			param->dump_size = default_stack_dump_size;
290 			dwarf_callchain_users = true;
291 
292 			tok = strtok_r(NULL, ",", &saveptr);
293 			if (tok) {
294 				unsigned long size = 0;
295 
296 				ret = get_stack_size(tok, &size);
297 				param->dump_size = size;
298 			}
299 		} else if (!strncmp(name, "lbr", sizeof("lbr"))) {
300 			if (!strtok_r(NULL, ",", &saveptr)) {
301 				param->record_mode = CALLCHAIN_LBR;
302 				ret = 0;
303 			} else
304 				pr_err("callchain: No more arguments "
305 					"needed for --call-graph lbr\n");
306 			break;
307 		} else {
308 			pr_err("callchain: Unknown --call-graph option "
309 			       "value: %s\n", arg);
310 			break;
311 		}
312 
313 	} while (0);
314 
315 	free(buf);
316 	return ret;
317 }
318 
319 int perf_callchain_config(const char *var, const char *value)
320 {
321 	char *endptr;
322 
323 	if (!strstarts(var, "call-graph."))
324 		return 0;
325 	var += sizeof("call-graph.") - 1;
326 
327 	if (!strcmp(var, "record-mode"))
328 		return parse_callchain_record_opt(value, &callchain_param);
329 	if (!strcmp(var, "dump-size")) {
330 		unsigned long size = 0;
331 		int ret;
332 
333 		ret = get_stack_size(value, &size);
334 		callchain_param.dump_size = size;
335 
336 		return ret;
337 	}
338 	if (!strcmp(var, "print-type")){
339 		int ret;
340 		ret = parse_callchain_mode(value);
341 		if (ret == -1)
342 			pr_err("Invalid callchain mode: %s\n", value);
343 		return ret;
344 	}
345 	if (!strcmp(var, "order")){
346 		int ret;
347 		ret = parse_callchain_order(value);
348 		if (ret == -1)
349 			pr_err("Invalid callchain order: %s\n", value);
350 		return ret;
351 	}
352 	if (!strcmp(var, "sort-key")){
353 		int ret;
354 		ret = parse_callchain_sort_key(value);
355 		if (ret == -1)
356 			pr_err("Invalid callchain sort key: %s\n", value);
357 		return ret;
358 	}
359 	if (!strcmp(var, "threshold")) {
360 		callchain_param.min_percent = strtod(value, &endptr);
361 		if (value == endptr) {
362 			pr_err("Invalid callchain threshold: %s\n", value);
363 			return -1;
364 		}
365 	}
366 	if (!strcmp(var, "print-limit")) {
367 		callchain_param.print_limit = strtod(value, &endptr);
368 		if (value == endptr) {
369 			pr_err("Invalid callchain print limit: %s\n", value);
370 			return -1;
371 		}
372 	}
373 
374 	return 0;
375 }
376 
377 static void
378 rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
379 		    enum chain_mode mode)
380 {
381 	struct rb_node **p = &root->rb_node;
382 	struct rb_node *parent = NULL;
383 	struct callchain_node *rnode;
384 	u64 chain_cumul = callchain_cumul_hits(chain);
385 
386 	while (*p) {
387 		u64 rnode_cumul;
388 
389 		parent = *p;
390 		rnode = rb_entry(parent, struct callchain_node, rb_node);
391 		rnode_cumul = callchain_cumul_hits(rnode);
392 
393 		switch (mode) {
394 		case CHAIN_FLAT:
395 		case CHAIN_FOLDED:
396 			if (rnode->hit < chain->hit)
397 				p = &(*p)->rb_left;
398 			else
399 				p = &(*p)->rb_right;
400 			break;
401 		case CHAIN_GRAPH_ABS: /* Falldown */
402 		case CHAIN_GRAPH_REL:
403 			if (rnode_cumul < chain_cumul)
404 				p = &(*p)->rb_left;
405 			else
406 				p = &(*p)->rb_right;
407 			break;
408 		case CHAIN_NONE:
409 		default:
410 			break;
411 		}
412 	}
413 
414 	rb_link_node(&chain->rb_node, parent, p);
415 	rb_insert_color(&chain->rb_node, root);
416 }
417 
418 static void
419 __sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
420 		  u64 min_hit)
421 {
422 	struct rb_node *n;
423 	struct callchain_node *child;
424 
425 	n = rb_first(&node->rb_root_in);
426 	while (n) {
427 		child = rb_entry(n, struct callchain_node, rb_node_in);
428 		n = rb_next(n);
429 
430 		__sort_chain_flat(rb_root, child, min_hit);
431 	}
432 
433 	if (node->hit && node->hit >= min_hit)
434 		rb_insert_callchain(rb_root, node, CHAIN_FLAT);
435 }
436 
437 /*
438  * Once we get every callchains from the stream, we can now
439  * sort them by hit
440  */
441 static void
442 sort_chain_flat(struct rb_root *rb_root, struct callchain_root *root,
443 		u64 min_hit, struct callchain_param *param __maybe_unused)
444 {
445 	*rb_root = RB_ROOT;
446 	__sort_chain_flat(rb_root, &root->node, min_hit);
447 }
448 
449 static void __sort_chain_graph_abs(struct callchain_node *node,
450 				   u64 min_hit)
451 {
452 	struct rb_node *n;
453 	struct callchain_node *child;
454 
455 	node->rb_root = RB_ROOT;
456 	n = rb_first(&node->rb_root_in);
457 
458 	while (n) {
459 		child = rb_entry(n, struct callchain_node, rb_node_in);
460 		n = rb_next(n);
461 
462 		__sort_chain_graph_abs(child, min_hit);
463 		if (callchain_cumul_hits(child) >= min_hit)
464 			rb_insert_callchain(&node->rb_root, child,
465 					    CHAIN_GRAPH_ABS);
466 	}
467 }
468 
469 static void
470 sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_root *chain_root,
471 		     u64 min_hit, struct callchain_param *param __maybe_unused)
472 {
473 	__sort_chain_graph_abs(&chain_root->node, min_hit);
474 	rb_root->rb_node = chain_root->node.rb_root.rb_node;
475 }
476 
477 static void __sort_chain_graph_rel(struct callchain_node *node,
478 				   double min_percent)
479 {
480 	struct rb_node *n;
481 	struct callchain_node *child;
482 	u64 min_hit;
483 
484 	node->rb_root = RB_ROOT;
485 	min_hit = ceil(node->children_hit * min_percent);
486 
487 	n = rb_first(&node->rb_root_in);
488 	while (n) {
489 		child = rb_entry(n, struct callchain_node, rb_node_in);
490 		n = rb_next(n);
491 
492 		__sort_chain_graph_rel(child, min_percent);
493 		if (callchain_cumul_hits(child) >= min_hit)
494 			rb_insert_callchain(&node->rb_root, child,
495 					    CHAIN_GRAPH_REL);
496 	}
497 }
498 
499 static void
500 sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_root *chain_root,
501 		     u64 min_hit __maybe_unused, struct callchain_param *param)
502 {
503 	__sort_chain_graph_rel(&chain_root->node, param->min_percent / 100.0);
504 	rb_root->rb_node = chain_root->node.rb_root.rb_node;
505 }
506 
507 int callchain_register_param(struct callchain_param *param)
508 {
509 	switch (param->mode) {
510 	case CHAIN_GRAPH_ABS:
511 		param->sort = sort_chain_graph_abs;
512 		break;
513 	case CHAIN_GRAPH_REL:
514 		param->sort = sort_chain_graph_rel;
515 		break;
516 	case CHAIN_FLAT:
517 	case CHAIN_FOLDED:
518 		param->sort = sort_chain_flat;
519 		break;
520 	case CHAIN_NONE:
521 	default:
522 		return -1;
523 	}
524 	return 0;
525 }
526 
527 /*
528  * Create a child for a parent. If inherit_children, then the new child
529  * will become the new parent of it's parent children
530  */
531 static struct callchain_node *
532 create_child(struct callchain_node *parent, bool inherit_children)
533 {
534 	struct callchain_node *new;
535 
536 	new = zalloc(sizeof(*new));
537 	if (!new) {
538 		perror("not enough memory to create child for code path tree");
539 		return NULL;
540 	}
541 	new->parent = parent;
542 	INIT_LIST_HEAD(&new->val);
543 	INIT_LIST_HEAD(&new->parent_val);
544 
545 	if (inherit_children) {
546 		struct rb_node *n;
547 		struct callchain_node *child;
548 
549 		new->rb_root_in = parent->rb_root_in;
550 		parent->rb_root_in = RB_ROOT;
551 
552 		n = rb_first(&new->rb_root_in);
553 		while (n) {
554 			child = rb_entry(n, struct callchain_node, rb_node_in);
555 			child->parent = new;
556 			n = rb_next(n);
557 		}
558 
559 		/* make it the first child */
560 		rb_link_node(&new->rb_node_in, NULL, &parent->rb_root_in.rb_node);
561 		rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
562 	}
563 
564 	return new;
565 }
566 
567 
568 /*
569  * Fill the node with callchain values
570  */
571 static int
572 fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
573 {
574 	struct callchain_cursor_node *cursor_node;
575 
576 	node->val_nr = cursor->nr - cursor->pos;
577 	if (!node->val_nr)
578 		pr_warning("Warning: empty node in callchain tree\n");
579 
580 	cursor_node = callchain_cursor_current(cursor);
581 
582 	while (cursor_node) {
583 		struct callchain_list *call;
584 
585 		call = zalloc(sizeof(*call));
586 		if (!call) {
587 			perror("not enough memory for the code path tree");
588 			return -1;
589 		}
590 		call->ip = cursor_node->ip;
591 		call->ms = cursor_node->ms;
592 		map__get(call->ms.map);
593 		call->srcline = cursor_node->srcline;
594 
595 		if (cursor_node->branch) {
596 			call->branch_count = 1;
597 
598 			if (cursor_node->branch_from) {
599 				/*
600 				 * branch_from is set with value somewhere else
601 				 * to imply it's "to" of a branch.
602 				 */
603 				call->brtype_stat.branch_to = true;
604 
605 				if (cursor_node->branch_flags.predicted)
606 					call->predicted_count = 1;
607 
608 				if (cursor_node->branch_flags.abort)
609 					call->abort_count = 1;
610 
611 				branch_type_count(&call->brtype_stat,
612 						  &cursor_node->branch_flags,
613 						  cursor_node->branch_from,
614 						  cursor_node->ip);
615 			} else {
616 				/*
617 				 * It's "from" of a branch
618 				 */
619 				call->brtype_stat.branch_to = false;
620 				call->cycles_count =
621 					cursor_node->branch_flags.cycles;
622 				call->iter_count = cursor_node->nr_loop_iter;
623 				call->iter_cycles = cursor_node->iter_cycles;
624 			}
625 		}
626 
627 		list_add_tail(&call->list, &node->val);
628 
629 		callchain_cursor_advance(cursor);
630 		cursor_node = callchain_cursor_current(cursor);
631 	}
632 	return 0;
633 }
634 
635 static struct callchain_node *
636 add_child(struct callchain_node *parent,
637 	  struct callchain_cursor *cursor,
638 	  u64 period)
639 {
640 	struct callchain_node *new;
641 
642 	new = create_child(parent, false);
643 	if (new == NULL)
644 		return NULL;
645 
646 	if (fill_node(new, cursor) < 0) {
647 		struct callchain_list *call, *tmp;
648 
649 		list_for_each_entry_safe(call, tmp, &new->val, list) {
650 			list_del_init(&call->list);
651 			map__zput(call->ms.map);
652 			free(call);
653 		}
654 		free(new);
655 		return NULL;
656 	}
657 
658 	new->children_hit = 0;
659 	new->hit = period;
660 	new->children_count = 0;
661 	new->count = 1;
662 	return new;
663 }
664 
665 enum match_result {
666 	MATCH_ERROR  = -1,
667 	MATCH_EQ,
668 	MATCH_LT,
669 	MATCH_GT,
670 };
671 
672 static enum match_result match_chain_strings(const char *left,
673 					     const char *right)
674 {
675 	enum match_result ret = MATCH_EQ;
676 	int cmp;
677 
678 	if (left && right)
679 		cmp = strcmp(left, right);
680 	else if (!left && right)
681 		cmp = 1;
682 	else if (left && !right)
683 		cmp = -1;
684 	else
685 		return MATCH_ERROR;
686 
687 	if (cmp != 0)
688 		ret = cmp < 0 ? MATCH_LT : MATCH_GT;
689 
690 	return ret;
691 }
692 
693 /*
694  * We need to always use relative addresses because we're aggregating
695  * callchains from multiple threads, i.e. different address spaces, so
696  * comparing absolute addresses make no sense as a symbol in a DSO may end up
697  * in a different address when used in a different binary or even the same
698  * binary but with some sort of address randomization technique, thus we need
699  * to compare just relative addresses. -acme
700  */
701 static enum match_result match_chain_dso_addresses(struct map *left_map, u64 left_ip,
702 						   struct map *right_map, u64 right_ip)
703 {
704 	struct dso *left_dso = left_map ? left_map->dso : NULL;
705 	struct dso *right_dso = right_map ? right_map->dso : NULL;
706 
707 	if (left_dso != right_dso)
708 		return left_dso < right_dso ? MATCH_LT : MATCH_GT;
709 
710 	if (left_ip != right_ip)
711  		return left_ip < right_ip ? MATCH_LT : MATCH_GT;
712 
713 	return MATCH_EQ;
714 }
715 
716 static enum match_result match_chain(struct callchain_cursor_node *node,
717 				     struct callchain_list *cnode)
718 {
719 	enum match_result match = MATCH_ERROR;
720 
721 	switch (callchain_param.key) {
722 	case CCKEY_SRCLINE:
723 		match = match_chain_strings(cnode->srcline, node->srcline);
724 		if (match != MATCH_ERROR)
725 			break;
726 		/* otherwise fall-back to symbol-based comparison below */
727 		__fallthrough;
728 	case CCKEY_FUNCTION:
729 		if (node->ms.sym && cnode->ms.sym) {
730 			/*
731 			 * Compare inlined frames based on their symbol name
732 			 * because different inlined frames will have the same
733 			 * symbol start. Otherwise do a faster comparison based
734 			 * on the symbol start address.
735 			 */
736 			if (cnode->ms.sym->inlined || node->ms.sym->inlined) {
737 				match = match_chain_strings(cnode->ms.sym->name,
738 							    node->ms.sym->name);
739 				if (match != MATCH_ERROR)
740 					break;
741 			} else {
742 				match = match_chain_dso_addresses(cnode->ms.map, cnode->ms.sym->start,
743 								  node->ms.map, node->ms.sym->start);
744 				break;
745 			}
746 		}
747 		/* otherwise fall-back to IP-based comparison below */
748 		__fallthrough;
749 	case CCKEY_ADDRESS:
750 	default:
751 		match = match_chain_dso_addresses(cnode->ms.map, cnode->ip, node->ms.map, node->ip);
752 		break;
753 	}
754 
755 	if (match == MATCH_EQ && node->branch) {
756 		cnode->branch_count++;
757 
758 		if (node->branch_from) {
759 			/*
760 			 * It's "to" of a branch
761 			 */
762 			cnode->brtype_stat.branch_to = true;
763 
764 			if (node->branch_flags.predicted)
765 				cnode->predicted_count++;
766 
767 			if (node->branch_flags.abort)
768 				cnode->abort_count++;
769 
770 			branch_type_count(&cnode->brtype_stat,
771 					  &node->branch_flags,
772 					  node->branch_from,
773 					  node->ip);
774 		} else {
775 			/*
776 			 * It's "from" of a branch
777 			 */
778 			cnode->brtype_stat.branch_to = false;
779 			cnode->cycles_count += node->branch_flags.cycles;
780 			cnode->iter_count += node->nr_loop_iter;
781 			cnode->iter_cycles += node->iter_cycles;
782 			cnode->from_count++;
783 		}
784 	}
785 
786 	return match;
787 }
788 
789 /*
790  * Split the parent in two parts (a new child is created) and
791  * give a part of its callchain to the created child.
792  * Then create another child to host the given callchain of new branch
793  */
794 static int
795 split_add_child(struct callchain_node *parent,
796 		struct callchain_cursor *cursor,
797 		struct callchain_list *to_split,
798 		u64 idx_parents, u64 idx_local, u64 period)
799 {
800 	struct callchain_node *new;
801 	struct list_head *old_tail;
802 	unsigned int idx_total = idx_parents + idx_local;
803 
804 	/* split */
805 	new = create_child(parent, true);
806 	if (new == NULL)
807 		return -1;
808 
809 	/* split the callchain and move a part to the new child */
810 	old_tail = parent->val.prev;
811 	list_del_range(&to_split->list, old_tail);
812 	new->val.next = &to_split->list;
813 	new->val.prev = old_tail;
814 	to_split->list.prev = &new->val;
815 	old_tail->next = &new->val;
816 
817 	/* split the hits */
818 	new->hit = parent->hit;
819 	new->children_hit = parent->children_hit;
820 	parent->children_hit = callchain_cumul_hits(new);
821 	new->val_nr = parent->val_nr - idx_local;
822 	parent->val_nr = idx_local;
823 	new->count = parent->count;
824 	new->children_count = parent->children_count;
825 	parent->children_count = callchain_cumul_counts(new);
826 
827 	/* create a new child for the new branch if any */
828 	if (idx_total < cursor->nr) {
829 		struct callchain_node *first;
830 		struct callchain_list *cnode;
831 		struct callchain_cursor_node *node;
832 		struct rb_node *p, **pp;
833 
834 		parent->hit = 0;
835 		parent->children_hit += period;
836 		parent->count = 0;
837 		parent->children_count += 1;
838 
839 		node = callchain_cursor_current(cursor);
840 		new = add_child(parent, cursor, period);
841 		if (new == NULL)
842 			return -1;
843 
844 		/*
845 		 * This is second child since we moved parent's children
846 		 * to new (first) child above.
847 		 */
848 		p = parent->rb_root_in.rb_node;
849 		first = rb_entry(p, struct callchain_node, rb_node_in);
850 		cnode = list_first_entry(&first->val, struct callchain_list,
851 					 list);
852 
853 		if (match_chain(node, cnode) == MATCH_LT)
854 			pp = &p->rb_left;
855 		else
856 			pp = &p->rb_right;
857 
858 		rb_link_node(&new->rb_node_in, p, pp);
859 		rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
860 	} else {
861 		parent->hit = period;
862 		parent->count = 1;
863 	}
864 	return 0;
865 }
866 
867 static enum match_result
868 append_chain(struct callchain_node *root,
869 	     struct callchain_cursor *cursor,
870 	     u64 period);
871 
872 static int
873 append_chain_children(struct callchain_node *root,
874 		      struct callchain_cursor *cursor,
875 		      u64 period)
876 {
877 	struct callchain_node *rnode;
878 	struct callchain_cursor_node *node;
879 	struct rb_node **p = &root->rb_root_in.rb_node;
880 	struct rb_node *parent = NULL;
881 
882 	node = callchain_cursor_current(cursor);
883 	if (!node)
884 		return -1;
885 
886 	/* lookup in children */
887 	while (*p) {
888 		enum match_result ret;
889 
890 		parent = *p;
891 		rnode = rb_entry(parent, struct callchain_node, rb_node_in);
892 
893 		/* If at least first entry matches, rely to children */
894 		ret = append_chain(rnode, cursor, period);
895 		if (ret == MATCH_EQ)
896 			goto inc_children_hit;
897 		if (ret == MATCH_ERROR)
898 			return -1;
899 
900 		if (ret == MATCH_LT)
901 			p = &parent->rb_left;
902 		else
903 			p = &parent->rb_right;
904 	}
905 	/* nothing in children, add to the current node */
906 	rnode = add_child(root, cursor, period);
907 	if (rnode == NULL)
908 		return -1;
909 
910 	rb_link_node(&rnode->rb_node_in, parent, p);
911 	rb_insert_color(&rnode->rb_node_in, &root->rb_root_in);
912 
913 inc_children_hit:
914 	root->children_hit += period;
915 	root->children_count++;
916 	return 0;
917 }
918 
919 static enum match_result
920 append_chain(struct callchain_node *root,
921 	     struct callchain_cursor *cursor,
922 	     u64 period)
923 {
924 	struct callchain_list *cnode;
925 	u64 start = cursor->pos;
926 	bool found = false;
927 	u64 matches;
928 	enum match_result cmp = MATCH_ERROR;
929 
930 	/*
931 	 * Lookup in the current node
932 	 * If we have a symbol, then compare the start to match
933 	 * anywhere inside a function, unless function
934 	 * mode is disabled.
935 	 */
936 	list_for_each_entry(cnode, &root->val, list) {
937 		struct callchain_cursor_node *node;
938 
939 		node = callchain_cursor_current(cursor);
940 		if (!node)
941 			break;
942 
943 		cmp = match_chain(node, cnode);
944 		if (cmp != MATCH_EQ)
945 			break;
946 
947 		found = true;
948 
949 		callchain_cursor_advance(cursor);
950 	}
951 
952 	/* matches not, relay no the parent */
953 	if (!found) {
954 		WARN_ONCE(cmp == MATCH_ERROR, "Chain comparison error\n");
955 		return cmp;
956 	}
957 
958 	matches = cursor->pos - start;
959 
960 	/* we match only a part of the node. Split it and add the new chain */
961 	if (matches < root->val_nr) {
962 		if (split_add_child(root, cursor, cnode, start, matches,
963 				    period) < 0)
964 			return MATCH_ERROR;
965 
966 		return MATCH_EQ;
967 	}
968 
969 	/* we match 100% of the path, increment the hit */
970 	if (matches == root->val_nr && cursor->pos == cursor->nr) {
971 		root->hit += period;
972 		root->count++;
973 		return MATCH_EQ;
974 	}
975 
976 	/* We match the node and still have a part remaining */
977 	if (append_chain_children(root, cursor, period) < 0)
978 		return MATCH_ERROR;
979 
980 	return MATCH_EQ;
981 }
982 
983 int callchain_append(struct callchain_root *root,
984 		     struct callchain_cursor *cursor,
985 		     u64 period)
986 {
987 	if (!cursor->nr)
988 		return 0;
989 
990 	callchain_cursor_commit(cursor);
991 
992 	if (append_chain_children(&root->node, cursor, period) < 0)
993 		return -1;
994 
995 	if (cursor->nr > root->max_depth)
996 		root->max_depth = cursor->nr;
997 
998 	return 0;
999 }
1000 
1001 static int
1002 merge_chain_branch(struct callchain_cursor *cursor,
1003 		   struct callchain_node *dst, struct callchain_node *src)
1004 {
1005 	struct callchain_cursor_node **old_last = cursor->last;
1006 	struct callchain_node *child;
1007 	struct callchain_list *list, *next_list;
1008 	struct rb_node *n;
1009 	int old_pos = cursor->nr;
1010 	int err = 0;
1011 
1012 	list_for_each_entry_safe(list, next_list, &src->val, list) {
1013 		callchain_cursor_append(cursor, list->ip, &list->ms,
1014 					false, NULL, 0, 0, 0, list->srcline);
1015 		list_del_init(&list->list);
1016 		map__zput(list->ms.map);
1017 		free(list);
1018 	}
1019 
1020 	if (src->hit) {
1021 		callchain_cursor_commit(cursor);
1022 		if (append_chain_children(dst, cursor, src->hit) < 0)
1023 			return -1;
1024 	}
1025 
1026 	n = rb_first(&src->rb_root_in);
1027 	while (n) {
1028 		child = container_of(n, struct callchain_node, rb_node_in);
1029 		n = rb_next(n);
1030 		rb_erase(&child->rb_node_in, &src->rb_root_in);
1031 
1032 		err = merge_chain_branch(cursor, dst, child);
1033 		if (err)
1034 			break;
1035 
1036 		free(child);
1037 	}
1038 
1039 	cursor->nr = old_pos;
1040 	cursor->last = old_last;
1041 
1042 	return err;
1043 }
1044 
1045 int callchain_merge(struct callchain_cursor *cursor,
1046 		    struct callchain_root *dst, struct callchain_root *src)
1047 {
1048 	return merge_chain_branch(cursor, &dst->node, &src->node);
1049 }
1050 
1051 int callchain_cursor_append(struct callchain_cursor *cursor,
1052 			    u64 ip, struct map_symbol *ms,
1053 			    bool branch, struct branch_flags *flags,
1054 			    int nr_loop_iter, u64 iter_cycles, u64 branch_from,
1055 			    const char *srcline)
1056 {
1057 	struct callchain_cursor_node *node = *cursor->last;
1058 
1059 	if (!node) {
1060 		node = calloc(1, sizeof(*node));
1061 		if (!node)
1062 			return -ENOMEM;
1063 
1064 		*cursor->last = node;
1065 	}
1066 
1067 	node->ip = ip;
1068 	map__zput(node->ms.map);
1069 	node->ms = *ms;
1070 	map__get(node->ms.map);
1071 	node->branch = branch;
1072 	node->nr_loop_iter = nr_loop_iter;
1073 	node->iter_cycles = iter_cycles;
1074 	node->srcline = srcline;
1075 
1076 	if (flags)
1077 		memcpy(&node->branch_flags, flags,
1078 			sizeof(struct branch_flags));
1079 
1080 	node->branch_from = branch_from;
1081 	cursor->nr++;
1082 
1083 	cursor->last = &node->next;
1084 
1085 	return 0;
1086 }
1087 
1088 int sample__resolve_callchain(struct perf_sample *sample,
1089 			      struct callchain_cursor *cursor, struct symbol **parent,
1090 			      struct evsel *evsel, struct addr_location *al,
1091 			      int max_stack)
1092 {
1093 	if (sample->callchain == NULL && !symbol_conf.show_branchflag_count)
1094 		return 0;
1095 
1096 	if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain ||
1097 	    perf_hpp_list.parent || symbol_conf.show_branchflag_count) {
1098 		return thread__resolve_callchain(al->thread, cursor, evsel, sample,
1099 						 parent, al, max_stack);
1100 	}
1101 	return 0;
1102 }
1103 
1104 int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample)
1105 {
1106 	if ((!symbol_conf.use_callchain || sample->callchain == NULL) &&
1107 		!symbol_conf.show_branchflag_count)
1108 		return 0;
1109 	return callchain_append(he->callchain, &callchain_cursor, sample->period);
1110 }
1111 
1112 int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
1113 			bool hide_unresolved)
1114 {
1115 	al->maps = node->ms.maps;
1116 	al->map = node->ms.map;
1117 	al->sym = node->ms.sym;
1118 	al->srcline = node->srcline;
1119 	al->addr = node->ip;
1120 
1121 	if (al->sym == NULL) {
1122 		if (hide_unresolved)
1123 			return 0;
1124 		if (al->map == NULL)
1125 			goto out;
1126 	}
1127 
1128 	if (al->maps == machine__kernel_maps(al->maps->machine)) {
1129 		if (machine__is_host(al->maps->machine)) {
1130 			al->cpumode = PERF_RECORD_MISC_KERNEL;
1131 			al->level = 'k';
1132 		} else {
1133 			al->cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
1134 			al->level = 'g';
1135 		}
1136 	} else {
1137 		if (machine__is_host(al->maps->machine)) {
1138 			al->cpumode = PERF_RECORD_MISC_USER;
1139 			al->level = '.';
1140 		} else if (perf_guest) {
1141 			al->cpumode = PERF_RECORD_MISC_GUEST_USER;
1142 			al->level = 'u';
1143 		} else {
1144 			al->cpumode = PERF_RECORD_MISC_HYPERVISOR;
1145 			al->level = 'H';
1146 		}
1147 	}
1148 
1149 out:
1150 	return 1;
1151 }
1152 
1153 char *callchain_list__sym_name(struct callchain_list *cl,
1154 			       char *bf, size_t bfsize, bool show_dso)
1155 {
1156 	bool show_addr = callchain_param.key == CCKEY_ADDRESS;
1157 	bool show_srcline = show_addr || callchain_param.key == CCKEY_SRCLINE;
1158 	int printed;
1159 
1160 	if (cl->ms.sym) {
1161 		const char *inlined = cl->ms.sym->inlined ? " (inlined)" : "";
1162 
1163 		if (show_srcline && cl->srcline)
1164 			printed = scnprintf(bf, bfsize, "%s %s%s",
1165 					    cl->ms.sym->name, cl->srcline,
1166 					    inlined);
1167 		else
1168 			printed = scnprintf(bf, bfsize, "%s%s",
1169 					    cl->ms.sym->name, inlined);
1170 	} else
1171 		printed = scnprintf(bf, bfsize, "%#" PRIx64, cl->ip);
1172 
1173 	if (show_dso)
1174 		scnprintf(bf + printed, bfsize - printed, " %s",
1175 			  cl->ms.map ?
1176 			  cl->ms.map->dso->short_name :
1177 			  "unknown");
1178 
1179 	return bf;
1180 }
1181 
1182 char *callchain_node__scnprintf_value(struct callchain_node *node,
1183 				      char *bf, size_t bfsize, u64 total)
1184 {
1185 	double percent = 0.0;
1186 	u64 period = callchain_cumul_hits(node);
1187 	unsigned count = callchain_cumul_counts(node);
1188 
1189 	if (callchain_param.mode == CHAIN_FOLDED) {
1190 		period = node->hit;
1191 		count = node->count;
1192 	}
1193 
1194 	switch (callchain_param.value) {
1195 	case CCVAL_PERIOD:
1196 		scnprintf(bf, bfsize, "%"PRIu64, period);
1197 		break;
1198 	case CCVAL_COUNT:
1199 		scnprintf(bf, bfsize, "%u", count);
1200 		break;
1201 	case CCVAL_PERCENT:
1202 	default:
1203 		if (total)
1204 			percent = period * 100.0 / total;
1205 		scnprintf(bf, bfsize, "%.2f%%", percent);
1206 		break;
1207 	}
1208 	return bf;
1209 }
1210 
1211 int callchain_node__fprintf_value(struct callchain_node *node,
1212 				 FILE *fp, u64 total)
1213 {
1214 	double percent = 0.0;
1215 	u64 period = callchain_cumul_hits(node);
1216 	unsigned count = callchain_cumul_counts(node);
1217 
1218 	if (callchain_param.mode == CHAIN_FOLDED) {
1219 		period = node->hit;
1220 		count = node->count;
1221 	}
1222 
1223 	switch (callchain_param.value) {
1224 	case CCVAL_PERIOD:
1225 		return fprintf(fp, "%"PRIu64, period);
1226 	case CCVAL_COUNT:
1227 		return fprintf(fp, "%u", count);
1228 	case CCVAL_PERCENT:
1229 	default:
1230 		if (total)
1231 			percent = period * 100.0 / total;
1232 		return percent_color_fprintf(fp, "%.2f%%", percent);
1233 	}
1234 	return 0;
1235 }
1236 
1237 static void callchain_counts_value(struct callchain_node *node,
1238 				   u64 *branch_count, u64 *predicted_count,
1239 				   u64 *abort_count, u64 *cycles_count)
1240 {
1241 	struct callchain_list *clist;
1242 
1243 	list_for_each_entry(clist, &node->val, list) {
1244 		if (branch_count)
1245 			*branch_count += clist->branch_count;
1246 
1247 		if (predicted_count)
1248 			*predicted_count += clist->predicted_count;
1249 
1250 		if (abort_count)
1251 			*abort_count += clist->abort_count;
1252 
1253 		if (cycles_count)
1254 			*cycles_count += clist->cycles_count;
1255 	}
1256 }
1257 
1258 static int callchain_node_branch_counts_cumul(struct callchain_node *node,
1259 					      u64 *branch_count,
1260 					      u64 *predicted_count,
1261 					      u64 *abort_count,
1262 					      u64 *cycles_count)
1263 {
1264 	struct callchain_node *child;
1265 	struct rb_node *n;
1266 
1267 	n = rb_first(&node->rb_root_in);
1268 	while (n) {
1269 		child = rb_entry(n, struct callchain_node, rb_node_in);
1270 		n = rb_next(n);
1271 
1272 		callchain_node_branch_counts_cumul(child, branch_count,
1273 						   predicted_count,
1274 						   abort_count,
1275 						   cycles_count);
1276 
1277 		callchain_counts_value(child, branch_count,
1278 				       predicted_count, abort_count,
1279 				       cycles_count);
1280 	}
1281 
1282 	return 0;
1283 }
1284 
1285 int callchain_branch_counts(struct callchain_root *root,
1286 			    u64 *branch_count, u64 *predicted_count,
1287 			    u64 *abort_count, u64 *cycles_count)
1288 {
1289 	if (branch_count)
1290 		*branch_count = 0;
1291 
1292 	if (predicted_count)
1293 		*predicted_count = 0;
1294 
1295 	if (abort_count)
1296 		*abort_count = 0;
1297 
1298 	if (cycles_count)
1299 		*cycles_count = 0;
1300 
1301 	return callchain_node_branch_counts_cumul(&root->node,
1302 						  branch_count,
1303 						  predicted_count,
1304 						  abort_count,
1305 						  cycles_count);
1306 }
1307 
1308 static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int bfsize)
1309 {
1310 	return scnprintf(bf, bfsize, "%s%s:%" PRId64 "", (idx) ? " " : " (", str, value);
1311 }
1312 
1313 static int count_float_printf(int idx, const char *str, float value,
1314 			      char *bf, int bfsize, float threshold)
1315 {
1316 	if (threshold != 0.0 && value < threshold)
1317 		return 0;
1318 
1319 	return scnprintf(bf, bfsize, "%s%s:%.1f%%", (idx) ? " " : " (", str, value);
1320 }
1321 
1322 static int branch_to_str(char *bf, int bfsize,
1323 			 u64 branch_count, u64 predicted_count,
1324 			 u64 abort_count,
1325 			 struct branch_type_stat *brtype_stat)
1326 {
1327 	int printed, i = 0;
1328 
1329 	printed = branch_type_str(brtype_stat, bf, bfsize);
1330 	if (printed)
1331 		i++;
1332 
1333 	if (predicted_count < branch_count) {
1334 		printed += count_float_printf(i++, "predicted",
1335 				predicted_count * 100.0 / branch_count,
1336 				bf + printed, bfsize - printed, 0.0);
1337 	}
1338 
1339 	if (abort_count) {
1340 		printed += count_float_printf(i++, "abort",
1341 				abort_count * 100.0 / branch_count,
1342 				bf + printed, bfsize - printed, 0.1);
1343 	}
1344 
1345 	if (i)
1346 		printed += scnprintf(bf + printed, bfsize - printed, ")");
1347 
1348 	return printed;
1349 }
1350 
1351 static int branch_from_str(char *bf, int bfsize,
1352 			   u64 branch_count,
1353 			   u64 cycles_count, u64 iter_count,
1354 			   u64 iter_cycles, u64 from_count)
1355 {
1356 	int printed = 0, i = 0;
1357 	u64 cycles, v = 0;
1358 
1359 	cycles = cycles_count / branch_count;
1360 	if (cycles) {
1361 		printed += count_pri64_printf(i++, "cycles",
1362 				cycles,
1363 				bf + printed, bfsize - printed);
1364 	}
1365 
1366 	if (iter_count && from_count) {
1367 		v = iter_count / from_count;
1368 		if (v) {
1369 			printed += count_pri64_printf(i++, "iter",
1370 					v, bf + printed, bfsize - printed);
1371 
1372 			printed += count_pri64_printf(i++, "avg_cycles",
1373 					iter_cycles / iter_count,
1374 					bf + printed, bfsize - printed);
1375 		}
1376 	}
1377 
1378 	if (i)
1379 		printed += scnprintf(bf + printed, bfsize - printed, ")");
1380 
1381 	return printed;
1382 }
1383 
1384 static int counts_str_build(char *bf, int bfsize,
1385 			     u64 branch_count, u64 predicted_count,
1386 			     u64 abort_count, u64 cycles_count,
1387 			     u64 iter_count, u64 iter_cycles,
1388 			     u64 from_count,
1389 			     struct branch_type_stat *brtype_stat)
1390 {
1391 	int printed;
1392 
1393 	if (branch_count == 0)
1394 		return scnprintf(bf, bfsize, " (calltrace)");
1395 
1396 	if (brtype_stat->branch_to) {
1397 		printed = branch_to_str(bf, bfsize, branch_count,
1398 				predicted_count, abort_count, brtype_stat);
1399 	} else {
1400 		printed = branch_from_str(bf, bfsize, branch_count,
1401 				cycles_count, iter_count, iter_cycles,
1402 				from_count);
1403 	}
1404 
1405 	if (!printed)
1406 		bf[0] = 0;
1407 
1408 	return printed;
1409 }
1410 
1411 static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
1412 				   u64 branch_count, u64 predicted_count,
1413 				   u64 abort_count, u64 cycles_count,
1414 				   u64 iter_count, u64 iter_cycles,
1415 				   u64 from_count,
1416 				   struct branch_type_stat *brtype_stat)
1417 {
1418 	char str[256];
1419 
1420 	counts_str_build(str, sizeof(str), branch_count,
1421 			 predicted_count, abort_count, cycles_count,
1422 			 iter_count, iter_cycles, from_count, brtype_stat);
1423 
1424 	if (fp)
1425 		return fprintf(fp, "%s", str);
1426 
1427 	return scnprintf(bf, bfsize, "%s", str);
1428 }
1429 
1430 int callchain_list_counts__printf_value(struct callchain_list *clist,
1431 					FILE *fp, char *bf, int bfsize)
1432 {
1433 	u64 branch_count, predicted_count;
1434 	u64 abort_count, cycles_count;
1435 	u64 iter_count, iter_cycles;
1436 	u64 from_count;
1437 
1438 	branch_count = clist->branch_count;
1439 	predicted_count = clist->predicted_count;
1440 	abort_count = clist->abort_count;
1441 	cycles_count = clist->cycles_count;
1442 	iter_count = clist->iter_count;
1443 	iter_cycles = clist->iter_cycles;
1444 	from_count = clist->from_count;
1445 
1446 	return callchain_counts_printf(fp, bf, bfsize, branch_count,
1447 				       predicted_count, abort_count,
1448 				       cycles_count, iter_count, iter_cycles,
1449 				       from_count, &clist->brtype_stat);
1450 }
1451 
1452 static void free_callchain_node(struct callchain_node *node)
1453 {
1454 	struct callchain_list *list, *tmp;
1455 	struct callchain_node *child;
1456 	struct rb_node *n;
1457 
1458 	list_for_each_entry_safe(list, tmp, &node->parent_val, list) {
1459 		list_del_init(&list->list);
1460 		map__zput(list->ms.map);
1461 		free(list);
1462 	}
1463 
1464 	list_for_each_entry_safe(list, tmp, &node->val, list) {
1465 		list_del_init(&list->list);
1466 		map__zput(list->ms.map);
1467 		free(list);
1468 	}
1469 
1470 	n = rb_first(&node->rb_root_in);
1471 	while (n) {
1472 		child = container_of(n, struct callchain_node, rb_node_in);
1473 		n = rb_next(n);
1474 		rb_erase(&child->rb_node_in, &node->rb_root_in);
1475 
1476 		free_callchain_node(child);
1477 		free(child);
1478 	}
1479 }
1480 
1481 void free_callchain(struct callchain_root *root)
1482 {
1483 	if (!symbol_conf.use_callchain)
1484 		return;
1485 
1486 	free_callchain_node(&root->node);
1487 }
1488 
1489 static u64 decay_callchain_node(struct callchain_node *node)
1490 {
1491 	struct callchain_node *child;
1492 	struct rb_node *n;
1493 	u64 child_hits = 0;
1494 
1495 	n = rb_first(&node->rb_root_in);
1496 	while (n) {
1497 		child = container_of(n, struct callchain_node, rb_node_in);
1498 
1499 		child_hits += decay_callchain_node(child);
1500 		n = rb_next(n);
1501 	}
1502 
1503 	node->hit = (node->hit * 7) / 8;
1504 	node->children_hit = child_hits;
1505 
1506 	return node->hit;
1507 }
1508 
1509 void decay_callchain(struct callchain_root *root)
1510 {
1511 	if (!symbol_conf.use_callchain)
1512 		return;
1513 
1514 	decay_callchain_node(&root->node);
1515 }
1516 
1517 int callchain_node__make_parent_list(struct callchain_node *node)
1518 {
1519 	struct callchain_node *parent = node->parent;
1520 	struct callchain_list *chain, *new;
1521 	LIST_HEAD(head);
1522 
1523 	while (parent) {
1524 		list_for_each_entry_reverse(chain, &parent->val, list) {
1525 			new = malloc(sizeof(*new));
1526 			if (new == NULL)
1527 				goto out;
1528 			*new = *chain;
1529 			new->has_children = false;
1530 			map__get(new->ms.map);
1531 			list_add_tail(&new->list, &head);
1532 		}
1533 		parent = parent->parent;
1534 	}
1535 
1536 	list_for_each_entry_safe_reverse(chain, new, &head, list)
1537 		list_move_tail(&chain->list, &node->parent_val);
1538 
1539 	if (!list_empty(&node->parent_val)) {
1540 		chain = list_first_entry(&node->parent_val, struct callchain_list, list);
1541 		chain->has_children = rb_prev(&node->rb_node) || rb_next(&node->rb_node);
1542 
1543 		chain = list_first_entry(&node->val, struct callchain_list, list);
1544 		chain->has_children = false;
1545 	}
1546 	return 0;
1547 
1548 out:
1549 	list_for_each_entry_safe(chain, new, &head, list) {
1550 		list_del_init(&chain->list);
1551 		map__zput(chain->ms.map);
1552 		free(chain);
1553 	}
1554 	return -ENOMEM;
1555 }
1556 
1557 int callchain_cursor__copy(struct callchain_cursor *dst,
1558 			   struct callchain_cursor *src)
1559 {
1560 	int rc = 0;
1561 
1562 	callchain_cursor_reset(dst);
1563 	callchain_cursor_commit(src);
1564 
1565 	while (true) {
1566 		struct callchain_cursor_node *node;
1567 
1568 		node = callchain_cursor_current(src);
1569 		if (node == NULL)
1570 			break;
1571 
1572 		rc = callchain_cursor_append(dst, node->ip, &node->ms,
1573 					     node->branch, &node->branch_flags,
1574 					     node->nr_loop_iter,
1575 					     node->iter_cycles,
1576 					     node->branch_from, node->srcline);
1577 		if (rc)
1578 			break;
1579 
1580 		callchain_cursor_advance(src);
1581 	}
1582 
1583 	return rc;
1584 }
1585 
1586 /*
1587  * Initialize a cursor before adding entries inside, but keep
1588  * the previously allocated entries as a cache.
1589  */
1590 void callchain_cursor_reset(struct callchain_cursor *cursor)
1591 {
1592 	struct callchain_cursor_node *node;
1593 
1594 	cursor->nr = 0;
1595 	cursor->last = &cursor->first;
1596 
1597 	for (node = cursor->first; node != NULL; node = node->next)
1598 		map__zput(node->ms.map);
1599 }
1600 
1601 void callchain_param_setup(u64 sample_type, const char *arch)
1602 {
1603 	if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain) {
1604 		if ((sample_type & PERF_SAMPLE_REGS_USER) &&
1605 		    (sample_type & PERF_SAMPLE_STACK_USER)) {
1606 			callchain_param.record_mode = CALLCHAIN_DWARF;
1607 			dwarf_callchain_users = true;
1608 		} else if (sample_type & PERF_SAMPLE_BRANCH_STACK)
1609 			callchain_param.record_mode = CALLCHAIN_LBR;
1610 		else
1611 			callchain_param.record_mode = CALLCHAIN_FP;
1612 	}
1613 
1614 	/*
1615 	 * It's necessary to use libunwind to reliably determine the caller of
1616 	 * a leaf function on aarch64, as otherwise we cannot know whether to
1617 	 * start from the LR or FP.
1618 	 *
1619 	 * Always starting from the LR can result in duplicate or entirely
1620 	 * erroneous entries. Always skipping the LR and starting from the FP
1621 	 * can result in missing entries.
1622 	 */
1623 	if (callchain_param.record_mode == CALLCHAIN_FP && !strcmp(arch, "arm64"))
1624 		dwarf_callchain_users = true;
1625 }
1626 
1627 static bool chain_match(struct callchain_list *base_chain,
1628 			struct callchain_list *pair_chain)
1629 {
1630 	enum match_result match;
1631 
1632 	match = match_chain_strings(base_chain->srcline,
1633 				    pair_chain->srcline);
1634 	if (match != MATCH_ERROR)
1635 		return match == MATCH_EQ;
1636 
1637 	match = match_chain_dso_addresses(base_chain->ms.map,
1638 					  base_chain->ip,
1639 					  pair_chain->ms.map,
1640 					  pair_chain->ip);
1641 
1642 	return match == MATCH_EQ;
1643 }
1644 
1645 bool callchain_cnode_matched(struct callchain_node *base_cnode,
1646 			     struct callchain_node *pair_cnode)
1647 {
1648 	struct callchain_list *base_chain, *pair_chain;
1649 	bool match = false;
1650 
1651 	pair_chain = list_first_entry(&pair_cnode->val,
1652 				      struct callchain_list,
1653 				      list);
1654 
1655 	list_for_each_entry(base_chain, &base_cnode->val, list) {
1656 		if (&pair_chain->list == &pair_cnode->val)
1657 			return false;
1658 
1659 		if (!base_chain->srcline || !pair_chain->srcline) {
1660 			pair_chain = list_next_entry(pair_chain, list);
1661 			continue;
1662 		}
1663 
1664 		match = chain_match(base_chain, pair_chain);
1665 		if (!match)
1666 			return false;
1667 
1668 		pair_chain = list_next_entry(pair_chain, list);
1669 	}
1670 
1671 	/*
1672 	 * Say chain1 is ABC, chain2 is ABCD, we consider they are
1673 	 * not fully matched.
1674 	 */
1675 	if (pair_chain && (&pair_chain->list != &pair_cnode->val))
1676 		return false;
1677 
1678 	return match;
1679 }
1680 
1681 static u64 count_callchain_hits(struct hist_entry *he)
1682 {
1683 	struct rb_root *root = &he->sorted_chain;
1684 	struct rb_node *rb_node = rb_first(root);
1685 	struct callchain_node *node;
1686 	u64 chain_hits = 0;
1687 
1688 	while (rb_node) {
1689 		node = rb_entry(rb_node, struct callchain_node, rb_node);
1690 		chain_hits += node->hit;
1691 		rb_node = rb_next(rb_node);
1692 	}
1693 
1694 	return chain_hits;
1695 }
1696 
1697 u64 callchain_total_hits(struct hists *hists)
1698 {
1699 	struct rb_node *next = rb_first_cached(&hists->entries);
1700 	u64 chain_hits = 0;
1701 
1702 	while (next) {
1703 		struct hist_entry *he = rb_entry(next, struct hist_entry,
1704 						 rb_node);
1705 
1706 		chain_hits += count_callchain_hits(he);
1707 		next = rb_next(&he->rb_node);
1708 	}
1709 
1710 	return chain_hits;
1711 }
1712 
1713 s64 callchain_avg_cycles(struct callchain_node *cnode)
1714 {
1715 	struct callchain_list *chain;
1716 	s64 cycles = 0;
1717 
1718 	list_for_each_entry(chain, &cnode->val, list) {
1719 		if (chain->srcline && chain->branch_count)
1720 			cycles += chain->cycles_count / chain->branch_count;
1721 	}
1722 
1723 	return cycles;
1724 }
1725