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
44struct 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 */
55bool dwarf_callchain_users;
56
57struct callchain_param callchain_param_default = {
58 CALLCHAIN_PARAM_DEFAULT
59};
60
61/* Used for thread-local struct callchain_cursor. */
62static pthread_key_t callchain_cursor;
63
64int parse_callchain_record_opt(const char *arg, struct callchain_param *param)
65{
66 return parse_callchain_record(arg, param);
67}
68
69static int parse_callchain_mode(const char *value)
70{
71 if (!strncmp(value, "graph", strlen(value))) {
72 callchain_param.mode = CHAIN_GRAPH_ABS;
73 return 0;
74 }
75 if (!strncmp(value, "flat", strlen(value))) {
76 callchain_param.mode = CHAIN_FLAT;
77 return 0;
78 }
79 if (!strncmp(value, "fractal", strlen(value))) {
80 callchain_param.mode = CHAIN_GRAPH_REL;
81 return 0;
82 }
83 if (!strncmp(value, "folded", strlen(value))) {
84 callchain_param.mode = CHAIN_FOLDED;
85 return 0;
86 }
87 return -1;
88}
89
90static int parse_callchain_order(const char *value)
91{
92 if (!strncmp(value, "caller", strlen(value))) {
93 callchain_param.order = ORDER_CALLER;
94 callchain_param.order_set = true;
95 return 0;
96 }
97 if (!strncmp(value, "callee", strlen(value))) {
98 callchain_param.order = ORDER_CALLEE;
99 callchain_param.order_set = true;
100 return 0;
101 }
102 return -1;
103}
104
105static int parse_callchain_sort_key(const char *value)
106{
107 if (!strncmp(value, "function", strlen(value))) {
108 callchain_param.key = CCKEY_FUNCTION;
109 return 0;
110 }
111 if (!strncmp(value, "address", strlen(value))) {
112 callchain_param.key = CCKEY_ADDRESS;
113 return 0;
114 }
115 if (!strncmp(value, "srcline", strlen(value))) {
116 callchain_param.key = CCKEY_SRCLINE;
117 return 0;
118 }
119 if (!strncmp(value, "branch", strlen(value))) {
120 callchain_param.branch_callstack = 1;
121 return 0;
122 }
123 return -1;
124}
125
126static int parse_callchain_value(const char *value)
127{
128 if (!strncmp(value, "percent", strlen(value))) {
129 callchain_param.value = CCVAL_PERCENT;
130 return 0;
131 }
132 if (!strncmp(value, "period", strlen(value))) {
133 callchain_param.value = CCVAL_PERIOD;
134 return 0;
135 }
136 if (!strncmp(value, "count", strlen(value))) {
137 callchain_param.value = CCVAL_COUNT;
138 return 0;
139 }
140 return -1;
141}
142
143static int get_stack_size(const char *str, unsigned long *_size)
144{
145 char *endptr;
146 unsigned long size;
147 unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
148
149 size = strtoul(str, &endptr, 0);
150
151 do {
152 if (*endptr)
153 break;
154
155 size = round_up(size, sizeof(u64));
156 if (!size || size > max_size)
157 break;
158
159 *_size = size;
160 return 0;
161
162 } while (0);
163
164 pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
165 max_size, str);
166 return -1;
167}
168
169static int
170__parse_callchain_report_opt(const char *arg, bool allow_record_opt)
171{
172 char *tok;
173 char *endptr, *saveptr = NULL;
174 bool minpcnt_set = false;
175 bool record_opt_set = false;
176 bool try_stack_size = false;
177
178 callchain_param.enabled = true;
179 symbol_conf.use_callchain = true;
180
181 if (!arg)
182 return 0;
183
184 while ((tok = strtok_r((char *)arg, ",", &saveptr)) != NULL) {
185 if (!strncmp(tok, "none", strlen(tok))) {
186 callchain_param.mode = CHAIN_NONE;
187 callchain_param.enabled = false;
188 symbol_conf.use_callchain = false;
189 return 0;
190 }
191
192 if (!parse_callchain_mode(value: tok) ||
193 !parse_callchain_order(value: tok) ||
194 !parse_callchain_sort_key(value: tok) ||
195 !parse_callchain_value(value: tok)) {
196 /* parsing ok - move on to the next */
197 try_stack_size = false;
198 goto next;
199 } else if (allow_record_opt && !record_opt_set) {
200 if (parse_callchain_record(arg: tok, param: &callchain_param))
201 goto try_numbers;
202
203 /* assume that number followed by 'dwarf' is stack size */
204 if (callchain_param.record_mode == CALLCHAIN_DWARF)
205 try_stack_size = true;
206
207 record_opt_set = true;
208 goto next;
209 }
210
211try_numbers:
212 if (try_stack_size) {
213 unsigned long size = 0;
214
215 if (get_stack_size(str: tok, size: &size) < 0)
216 return -1;
217 callchain_param.dump_size = size;
218 try_stack_size = false;
219 } else if (!minpcnt_set) {
220 /* try to get the min percent */
221 callchain_param.min_percent = strtod(tok, &endptr);
222 if (tok == endptr)
223 return -1;
224 minpcnt_set = true;
225 } else {
226 /* try print limit at last */
227 callchain_param.print_limit = strtoul(tok, &endptr, 0);
228 if (tok == endptr)
229 return -1;
230 }
231next:
232 arg = NULL;
233 }
234
235 if (callchain_register_param(param: &callchain_param) < 0) {
236 pr_err("Can't register callchain params\n");
237 return -1;
238 }
239 return 0;
240}
241
242int parse_callchain_report_opt(const char *arg)
243{
244 return __parse_callchain_report_opt(arg, allow_record_opt: false);
245}
246
247int parse_callchain_top_opt(const char *arg)
248{
249 return __parse_callchain_report_opt(arg, allow_record_opt: true);
250}
251
252int parse_callchain_record(const char *arg, struct callchain_param *param)
253{
254 char *tok, *name, *saveptr = NULL;
255 char *buf;
256 int ret = -1;
257
258 /* We need buffer that we know we can write to. */
259 buf = malloc(strlen(arg) + 1);
260 if (!buf)
261 return -ENOMEM;
262
263 strcpy(p: buf, q: arg);
264
265 tok = strtok_r((char *)buf, ",", &saveptr);
266 name = tok ? : (char *)buf;
267
268 do {
269 /* Framepointer style */
270 if (!strncmp(name, "fp", sizeof("fp"))) {
271 ret = 0;
272 param->record_mode = CALLCHAIN_FP;
273
274 tok = strtok_r(NULL, ",", &saveptr);
275 if (tok) {
276 unsigned long size;
277
278 size = strtoul(tok, &name, 0);
279 if (size < (unsigned) sysctl__max_stack())
280 param->max_stack = size;
281 }
282 break;
283
284 /* Dwarf style */
285 } else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
286 const unsigned long default_stack_dump_size = 8192;
287
288 ret = 0;
289 param->record_mode = CALLCHAIN_DWARF;
290 param->dump_size = default_stack_dump_size;
291 dwarf_callchain_users = true;
292
293 tok = strtok_r(NULL, ",", &saveptr);
294 if (tok) {
295 unsigned long size = 0;
296
297 ret = get_stack_size(str: tok, size: &size);
298 param->dump_size = size;
299 }
300 } else if (!strncmp(name, "lbr", sizeof("lbr"))) {
301 if (!strtok_r(NULL, ",", &saveptr)) {
302 param->record_mode = CALLCHAIN_LBR;
303 ret = 0;
304 } else
305 pr_err("callchain: No more arguments "
306 "needed for --call-graph lbr\n");
307 break;
308 } else {
309 pr_err("callchain: Unknown --call-graph option "
310 "value: %s\n", arg);
311 break;
312 }
313
314 } while (0);
315
316 free(buf);
317 return ret;
318}
319
320int perf_callchain_config(const char *var, const char *value)
321{
322 char *endptr;
323
324 if (!strstarts(str: var, prefix: "call-graph."))
325 return 0;
326 var += sizeof("call-graph.") - 1;
327
328 if (!strcmp(var, "record-mode"))
329 return parse_callchain_record_opt(arg: value, param: &callchain_param);
330 if (!strcmp(var, "dump-size")) {
331 unsigned long size = 0;
332 int ret;
333
334 ret = get_stack_size(str: value, size: &size);
335 callchain_param.dump_size = size;
336
337 return ret;
338 }
339 if (!strcmp(var, "print-type")){
340 int ret;
341 ret = parse_callchain_mode(value);
342 if (ret == -1)
343 pr_err("Invalid callchain mode: %s\n", value);
344 return ret;
345 }
346 if (!strcmp(var, "order")){
347 int ret;
348 ret = parse_callchain_order(value);
349 if (ret == -1)
350 pr_err("Invalid callchain order: %s\n", value);
351 return ret;
352 }
353 if (!strcmp(var, "sort-key")){
354 int ret;
355 ret = parse_callchain_sort_key(value);
356 if (ret == -1)
357 pr_err("Invalid callchain sort key: %s\n", value);
358 return ret;
359 }
360 if (!strcmp(var, "threshold")) {
361 callchain_param.min_percent = strtod(value, &endptr);
362 if (value == endptr) {
363 pr_err("Invalid callchain threshold: %s\n", value);
364 return -1;
365 }
366 }
367 if (!strcmp(var, "print-limit")) {
368 callchain_param.print_limit = strtod(value, &endptr);
369 if (value == endptr) {
370 pr_err("Invalid callchain print limit: %s\n", value);
371 return -1;
372 }
373 }
374
375 return 0;
376}
377
378static void
379rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
380 enum chain_mode mode)
381{
382 struct rb_node **p = &root->rb_node;
383 struct rb_node *parent = NULL;
384 struct callchain_node *rnode;
385 u64 chain_cumul = callchain_cumul_hits(node: chain);
386
387 while (*p) {
388 u64 rnode_cumul;
389
390 parent = *p;
391 rnode = rb_entry(parent, struct callchain_node, rb_node);
392 rnode_cumul = callchain_cumul_hits(node: rnode);
393
394 switch (mode) {
395 case CHAIN_FLAT:
396 case CHAIN_FOLDED:
397 if (rnode->hit < chain->hit)
398 p = &(*p)->rb_left;
399 else
400 p = &(*p)->rb_right;
401 break;
402 case CHAIN_GRAPH_ABS: /* Falldown */
403 case CHAIN_GRAPH_REL:
404 if (rnode_cumul < chain_cumul)
405 p = &(*p)->rb_left;
406 else
407 p = &(*p)->rb_right;
408 break;
409 case CHAIN_NONE:
410 default:
411 break;
412 }
413 }
414
415 rb_link_node(node: &chain->rb_node, parent, rb_link: p);
416 rb_insert_color(&chain->rb_node, root);
417}
418
419static void
420__sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
421 u64 min_hit)
422{
423 struct rb_node *n;
424 struct callchain_node *child;
425
426 n = rb_first(&node->rb_root_in);
427 while (n) {
428 child = rb_entry(n, struct callchain_node, rb_node_in);
429 n = rb_next(n);
430
431 __sort_chain_flat(rb_root, node: child, min_hit);
432 }
433
434 if (node->hit && node->hit >= min_hit)
435 rb_insert_callchain(root: rb_root, chain: node, mode: CHAIN_FLAT);
436}
437
438/*
439 * Once we get every callchains from the stream, we can now
440 * sort them by hit
441 */
442static void
443sort_chain_flat(struct rb_root *rb_root, struct callchain_root *root,
444 u64 min_hit, struct callchain_param *param __maybe_unused)
445{
446 *rb_root = RB_ROOT;
447 __sort_chain_flat(rb_root, node: &root->node, min_hit);
448}
449
450static void __sort_chain_graph_abs(struct callchain_node *node,
451 u64 min_hit)
452{
453 struct rb_node *n;
454 struct callchain_node *child;
455
456 node->rb_root = RB_ROOT;
457 n = rb_first(&node->rb_root_in);
458
459 while (n) {
460 child = rb_entry(n, struct callchain_node, rb_node_in);
461 n = rb_next(n);
462
463 __sort_chain_graph_abs(node: child, min_hit);
464 if (callchain_cumul_hits(node: child) >= min_hit)
465 rb_insert_callchain(root: &node->rb_root, chain: child,
466 mode: CHAIN_GRAPH_ABS);
467 }
468}
469
470static void
471sort_chain_graph_abs(struct rb_root *rb_root, struct callchain_root *chain_root,
472 u64 min_hit, struct callchain_param *param __maybe_unused)
473{
474 __sort_chain_graph_abs(node: &chain_root->node, min_hit);
475 rb_root->rb_node = chain_root->node.rb_root.rb_node;
476}
477
478static void __sort_chain_graph_rel(struct callchain_node *node,
479 double min_percent)
480{
481 struct rb_node *n;
482 struct callchain_node *child;
483 u64 min_hit;
484
485 node->rb_root = RB_ROOT;
486 min_hit = ceil(node->children_hit * min_percent);
487
488 n = rb_first(&node->rb_root_in);
489 while (n) {
490 child = rb_entry(n, struct callchain_node, rb_node_in);
491 n = rb_next(n);
492
493 __sort_chain_graph_rel(node: child, min_percent);
494 if (callchain_cumul_hits(node: child) >= min_hit)
495 rb_insert_callchain(root: &node->rb_root, chain: child,
496 mode: CHAIN_GRAPH_REL);
497 }
498}
499
500static void
501sort_chain_graph_rel(struct rb_root *rb_root, struct callchain_root *chain_root,
502 u64 min_hit __maybe_unused, struct callchain_param *param)
503{
504 __sort_chain_graph_rel(node: &chain_root->node, min_percent: param->min_percent / 100.0);
505 rb_root->rb_node = chain_root->node.rb_root.rb_node;
506}
507
508int callchain_register_param(struct callchain_param *param)
509{
510 switch (param->mode) {
511 case CHAIN_GRAPH_ABS:
512 param->sort = sort_chain_graph_abs;
513 break;
514 case CHAIN_GRAPH_REL:
515 param->sort = sort_chain_graph_rel;
516 break;
517 case CHAIN_FLAT:
518 case CHAIN_FOLDED:
519 param->sort = sort_chain_flat;
520 break;
521 case CHAIN_NONE:
522 default:
523 return -1;
524 }
525 return 0;
526}
527
528/*
529 * Create a child for a parent. If inherit_children, then the new child
530 * will become the new parent of it's parent children
531 */
532static struct callchain_node *
533create_child(struct callchain_node *parent, bool inherit_children)
534{
535 struct callchain_node *new;
536
537 new = zalloc(sizeof(*new));
538 if (!new) {
539 perror("not enough memory to create child for code path tree");
540 return NULL;
541 }
542 new->parent = parent;
543 INIT_LIST_HEAD(list: &new->val);
544 INIT_LIST_HEAD(list: &new->parent_val);
545
546 if (inherit_children) {
547 struct rb_node *n;
548 struct callchain_node *child;
549
550 new->rb_root_in = parent->rb_root_in;
551 parent->rb_root_in = RB_ROOT;
552
553 n = rb_first(&new->rb_root_in);
554 while (n) {
555 child = rb_entry(n, struct callchain_node, rb_node_in);
556 child->parent = new;
557 n = rb_next(n);
558 }
559
560 /* make it the first child */
561 rb_link_node(node: &new->rb_node_in, NULL, rb_link: &parent->rb_root_in.rb_node);
562 rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
563 }
564
565 return new;
566}
567
568
569/*
570 * Fill the node with callchain values
571 */
572static int
573fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
574{
575 struct callchain_cursor_node *cursor_node;
576
577 node->val_nr = cursor->nr - cursor->pos;
578 if (!node->val_nr)
579 pr_warning("Warning: empty node in callchain tree\n");
580
581 cursor_node = callchain_cursor_current(cursor);
582
583 while (cursor_node) {
584 struct callchain_list *call;
585
586 call = zalloc(sizeof(*call));
587 if (!call) {
588 perror("not enough memory for the code path tree");
589 return -ENOMEM;
590 }
591 call->ip = cursor_node->ip;
592 call->ms = cursor_node->ms;
593 call->ms.map = map__get(map: call->ms.map);
594 call->ms.maps = maps__get(maps: call->ms.maps);
595 call->srcline = cursor_node->srcline;
596
597 if (cursor_node->branch) {
598 call->branch_count = 1;
599
600 if (cursor_node->branch_from) {
601 /*
602 * branch_from is set with value somewhere else
603 * to imply it's "to" of a branch.
604 */
605 if (!call->brtype_stat) {
606 call->brtype_stat = zalloc(sizeof(*call->brtype_stat));
607 if (!call->brtype_stat) {
608 perror("not enough memory for the code path branch statistics");
609 free(call->brtype_stat);
610 return -ENOMEM;
611 }
612 }
613 call->brtype_stat->branch_to = true;
614
615 if (cursor_node->branch_flags.predicted)
616 call->predicted_count = 1;
617
618 if (cursor_node->branch_flags.abort)
619 call->abort_count = 1;
620
621 branch_type_count(st: call->brtype_stat,
622 flags: &cursor_node->branch_flags,
623 from: cursor_node->branch_from,
624 to: cursor_node->ip);
625 } else {
626 /*
627 * It's "from" of a branch
628 */
629 if (call->brtype_stat && call->brtype_stat->branch_to)
630 call->brtype_stat->branch_to = false;
631 call->cycles_count =
632 cursor_node->branch_flags.cycles;
633 call->iter_count = cursor_node->nr_loop_iter;
634 call->iter_cycles = cursor_node->iter_cycles;
635 }
636 }
637
638 list_add_tail(new: &call->list, head: &node->val);
639
640 callchain_cursor_advance(cursor);
641 cursor_node = callchain_cursor_current(cursor);
642 }
643 return 0;
644}
645
646static struct callchain_node *
647add_child(struct callchain_node *parent,
648 struct callchain_cursor *cursor,
649 u64 period)
650{
651 struct callchain_node *new;
652
653 new = create_child(parent, inherit_children: false);
654 if (new == NULL)
655 return NULL;
656
657 if (fill_node(node: new, cursor) < 0) {
658 struct callchain_list *call, *tmp;
659
660 list_for_each_entry_safe(call, tmp, &new->val, list) {
661 list_del_init(entry: &call->list);
662 map_symbol__exit(ms: &call->ms);
663 zfree(&call->brtype_stat);
664 free(call);
665 }
666 free(new);
667 return NULL;
668 }
669
670 new->children_hit = 0;
671 new->hit = period;
672 new->children_count = 0;
673 new->count = 1;
674 return new;
675}
676
677enum match_result {
678 MATCH_ERROR = -1,
679 MATCH_EQ,
680 MATCH_LT,
681 MATCH_GT,
682};
683
684static enum match_result match_chain_strings(const char *left,
685 const char *right)
686{
687 enum match_result ret = MATCH_EQ;
688 int cmp;
689
690 if (left && right)
691 cmp = strcmp(left, right);
692 else if (!left && right)
693 cmp = 1;
694 else if (left && !right)
695 cmp = -1;
696 else
697 return MATCH_ERROR;
698
699 if (cmp != 0)
700 ret = cmp < 0 ? MATCH_LT : MATCH_GT;
701
702 return ret;
703}
704
705/*
706 * We need to always use relative addresses because we're aggregating
707 * callchains from multiple threads, i.e. different address spaces, so
708 * comparing absolute addresses make no sense as a symbol in a DSO may end up
709 * in a different address when used in a different binary or even the same
710 * binary but with some sort of address randomization technique, thus we need
711 * to compare just relative addresses. -acme
712 */
713static enum match_result match_chain_dso_addresses(struct map *left_map, u64 left_ip,
714 struct map *right_map, u64 right_ip)
715{
716 struct dso *left_dso = left_map ? map__dso(map: left_map) : NULL;
717 struct dso *right_dso = right_map ? map__dso(map: right_map) : NULL;
718
719 if (left_dso != right_dso)
720 return left_dso < right_dso ? MATCH_LT : MATCH_GT;
721
722 if (left_ip != right_ip)
723 return left_ip < right_ip ? MATCH_LT : MATCH_GT;
724
725 return MATCH_EQ;
726}
727
728static enum match_result match_chain(struct callchain_cursor_node *node,
729 struct callchain_list *cnode)
730{
731 enum match_result match = MATCH_ERROR;
732
733 switch (callchain_param.key) {
734 case CCKEY_SRCLINE:
735 match = match_chain_strings(left: cnode->srcline, right: node->srcline);
736 if (match != MATCH_ERROR)
737 break;
738 /* otherwise fall-back to symbol-based comparison below */
739 fallthrough;
740 case CCKEY_FUNCTION:
741 if (node->ms.sym && cnode->ms.sym) {
742 /*
743 * Compare inlined frames based on their symbol name
744 * because different inlined frames will have the same
745 * symbol start. Otherwise do a faster comparison based
746 * on the symbol start address.
747 */
748 if (cnode->ms.sym->inlined || node->ms.sym->inlined) {
749 match = match_chain_strings(left: cnode->ms.sym->name,
750 right: node->ms.sym->name);
751 if (match != MATCH_ERROR)
752 break;
753 } else {
754 match = match_chain_dso_addresses(left_map: cnode->ms.map, left_ip: cnode->ms.sym->start,
755 right_map: node->ms.map, right_ip: node->ms.sym->start);
756 break;
757 }
758 }
759 /* otherwise fall-back to IP-based comparison below */
760 fallthrough;
761 case CCKEY_ADDRESS:
762 default:
763 match = match_chain_dso_addresses(left_map: cnode->ms.map, left_ip: cnode->ip, right_map: node->ms.map, right_ip: node->ip);
764 break;
765 }
766
767 if (match == MATCH_EQ && node->branch) {
768 cnode->branch_count++;
769
770 if (node->branch_from) {
771 /*
772 * It's "to" of a branch
773 */
774 if (!cnode->brtype_stat) {
775 cnode->brtype_stat = zalloc(sizeof(*cnode->brtype_stat));
776 if (!cnode->brtype_stat) {
777 perror("not enough memory for the code path branch statistics");
778 return MATCH_ERROR;
779 }
780 }
781 cnode->brtype_stat->branch_to = true;
782
783 if (node->branch_flags.predicted)
784 cnode->predicted_count++;
785
786 if (node->branch_flags.abort)
787 cnode->abort_count++;
788
789 branch_type_count(st: cnode->brtype_stat,
790 flags: &node->branch_flags,
791 from: node->branch_from,
792 to: node->ip);
793 } else {
794 /*
795 * It's "from" of a branch
796 */
797 if (cnode->brtype_stat && cnode->brtype_stat->branch_to)
798 cnode->brtype_stat->branch_to = false;
799 cnode->cycles_count += node->branch_flags.cycles;
800 cnode->iter_count += node->nr_loop_iter;
801 cnode->iter_cycles += node->iter_cycles;
802 cnode->from_count++;
803 }
804 }
805
806 return match;
807}
808
809/*
810 * Split the parent in two parts (a new child is created) and
811 * give a part of its callchain to the created child.
812 * Then create another child to host the given callchain of new branch
813 */
814static int
815split_add_child(struct callchain_node *parent,
816 struct callchain_cursor *cursor,
817 struct callchain_list *to_split,
818 u64 idx_parents, u64 idx_local, u64 period)
819{
820 struct callchain_node *new;
821 struct list_head *old_tail;
822 unsigned int idx_total = idx_parents + idx_local;
823
824 /* split */
825 new = create_child(parent, inherit_children: true);
826 if (new == NULL)
827 return -1;
828
829 /* split the callchain and move a part to the new child */
830 old_tail = parent->val.prev;
831 list_del_range(&to_split->list, old_tail);
832 new->val.next = &to_split->list;
833 new->val.prev = old_tail;
834 to_split->list.prev = &new->val;
835 old_tail->next = &new->val;
836
837 /* split the hits */
838 new->hit = parent->hit;
839 new->children_hit = parent->children_hit;
840 parent->children_hit = callchain_cumul_hits(node: new);
841 new->val_nr = parent->val_nr - idx_local;
842 parent->val_nr = idx_local;
843 new->count = parent->count;
844 new->children_count = parent->children_count;
845 parent->children_count = callchain_cumul_counts(node: new);
846
847 /* create a new child for the new branch if any */
848 if (idx_total < cursor->nr) {
849 struct callchain_node *first;
850 struct callchain_list *cnode;
851 struct callchain_cursor_node *node;
852 struct rb_node *p, **pp;
853
854 parent->hit = 0;
855 parent->children_hit += period;
856 parent->count = 0;
857 parent->children_count += 1;
858
859 node = callchain_cursor_current(cursor);
860 new = add_child(parent, cursor, period);
861 if (new == NULL)
862 return -1;
863
864 /*
865 * This is second child since we moved parent's children
866 * to new (first) child above.
867 */
868 p = parent->rb_root_in.rb_node;
869 first = rb_entry(p, struct callchain_node, rb_node_in);
870 cnode = list_first_entry(&first->val, struct callchain_list,
871 list);
872
873 if (match_chain(node, cnode) == MATCH_LT)
874 pp = &p->rb_left;
875 else
876 pp = &p->rb_right;
877
878 rb_link_node(node: &new->rb_node_in, parent: p, rb_link: pp);
879 rb_insert_color(&new->rb_node_in, &parent->rb_root_in);
880 } else {
881 parent->hit = period;
882 parent->count = 1;
883 }
884 return 0;
885}
886
887static enum match_result
888append_chain(struct callchain_node *root,
889 struct callchain_cursor *cursor,
890 u64 period);
891
892static int
893append_chain_children(struct callchain_node *root,
894 struct callchain_cursor *cursor,
895 u64 period)
896{
897 struct callchain_node *rnode;
898 struct callchain_cursor_node *node;
899 struct rb_node **p = &root->rb_root_in.rb_node;
900 struct rb_node *parent = NULL;
901
902 node = callchain_cursor_current(cursor);
903 if (!node)
904 return -1;
905
906 /* lookup in children */
907 while (*p) {
908 enum match_result ret;
909
910 parent = *p;
911 rnode = rb_entry(parent, struct callchain_node, rb_node_in);
912
913 /* If at least first entry matches, rely to children */
914 ret = append_chain(root: rnode, cursor, period);
915 if (ret == MATCH_EQ)
916 goto inc_children_hit;
917 if (ret == MATCH_ERROR)
918 return -1;
919
920 if (ret == MATCH_LT)
921 p = &parent->rb_left;
922 else
923 p = &parent->rb_right;
924 }
925 /* nothing in children, add to the current node */
926 rnode = add_child(parent: root, cursor, period);
927 if (rnode == NULL)
928 return -1;
929
930 rb_link_node(node: &rnode->rb_node_in, parent, rb_link: p);
931 rb_insert_color(&rnode->rb_node_in, &root->rb_root_in);
932
933inc_children_hit:
934 root->children_hit += period;
935 root->children_count++;
936 return 0;
937}
938
939static enum match_result
940append_chain(struct callchain_node *root,
941 struct callchain_cursor *cursor,
942 u64 period)
943{
944 struct callchain_list *cnode;
945 u64 start = cursor->pos;
946 bool found = false;
947 u64 matches;
948 enum match_result cmp = MATCH_ERROR;
949
950 /*
951 * Lookup in the current node
952 * If we have a symbol, then compare the start to match
953 * anywhere inside a function, unless function
954 * mode is disabled.
955 */
956 list_for_each_entry(cnode, &root->val, list) {
957 struct callchain_cursor_node *node;
958
959 node = callchain_cursor_current(cursor);
960 if (!node)
961 break;
962
963 cmp = match_chain(node, cnode);
964 if (cmp != MATCH_EQ)
965 break;
966
967 found = true;
968
969 callchain_cursor_advance(cursor);
970 }
971
972 /* matches not, relay no the parent */
973 if (!found) {
974 WARN_ONCE(cmp == MATCH_ERROR, "Chain comparison error\n");
975 return cmp;
976 }
977
978 matches = cursor->pos - start;
979
980 /* we match only a part of the node. Split it and add the new chain */
981 if (matches < root->val_nr) {
982 if (split_add_child(parent: root, cursor, to_split: cnode, idx_parents: start, idx_local: matches,
983 period) < 0)
984 return MATCH_ERROR;
985
986 return MATCH_EQ;
987 }
988
989 /* we match 100% of the path, increment the hit */
990 if (matches == root->val_nr && cursor->pos == cursor->nr) {
991 root->hit += period;
992 root->count++;
993 return MATCH_EQ;
994 }
995
996 /* We match the node and still have a part remaining */
997 if (append_chain_children(root, cursor, period) < 0)
998 return MATCH_ERROR;
999
1000 return MATCH_EQ;
1001}
1002
1003int callchain_append(struct callchain_root *root,
1004 struct callchain_cursor *cursor,
1005 u64 period)
1006{
1007 if (cursor == NULL)
1008 return -1;
1009
1010 if (!cursor->nr)
1011 return 0;
1012
1013 callchain_cursor_commit(cursor);
1014
1015 if (append_chain_children(root: &root->node, cursor, period) < 0)
1016 return -1;
1017
1018 if (cursor->nr > root->max_depth)
1019 root->max_depth = cursor->nr;
1020
1021 return 0;
1022}
1023
1024static int
1025merge_chain_branch(struct callchain_cursor *cursor,
1026 struct callchain_node *dst, struct callchain_node *src)
1027{
1028 struct callchain_cursor_node **old_last = cursor->last;
1029 struct callchain_node *child;
1030 struct callchain_list *list, *next_list;
1031 struct rb_node *n;
1032 int old_pos = cursor->nr;
1033 int err = 0;
1034
1035 list_for_each_entry_safe(list, next_list, &src->val, list) {
1036 struct map_symbol ms = {
1037 .maps = maps__get(maps: list->ms.maps),
1038 .map = map__get(map: list->ms.map),
1039 };
1040 callchain_cursor_append(cursor, ip: list->ip, ms: &ms, branch: false, NULL, nr_loop_iter: 0, iter_cycles: 0, branch_from: 0, srcline: list->srcline);
1041 list_del_init(entry: &list->list);
1042 map_symbol__exit(ms: &ms);
1043 map_symbol__exit(ms: &list->ms);
1044 zfree(&list->brtype_stat);
1045 free(list);
1046 }
1047
1048 if (src->hit) {
1049 callchain_cursor_commit(cursor);
1050 if (append_chain_children(root: dst, cursor, period: src->hit) < 0)
1051 return -1;
1052 }
1053
1054 n = rb_first(&src->rb_root_in);
1055 while (n) {
1056 child = container_of(n, struct callchain_node, rb_node_in);
1057 n = rb_next(n);
1058 rb_erase(&child->rb_node_in, &src->rb_root_in);
1059
1060 err = merge_chain_branch(cursor, dst, src: child);
1061 if (err)
1062 break;
1063
1064 free(child);
1065 }
1066
1067 cursor->nr = old_pos;
1068 cursor->last = old_last;
1069
1070 return err;
1071}
1072
1073int callchain_merge(struct callchain_cursor *cursor,
1074 struct callchain_root *dst, struct callchain_root *src)
1075{
1076 return merge_chain_branch(cursor, dst: &dst->node, src: &src->node);
1077}
1078
1079int callchain_cursor_append(struct callchain_cursor *cursor,
1080 u64 ip, struct map_symbol *ms,
1081 bool branch, struct branch_flags *flags,
1082 int nr_loop_iter, u64 iter_cycles, u64 branch_from,
1083 const char *srcline)
1084{
1085 struct callchain_cursor_node *node = *cursor->last;
1086
1087 if (!node) {
1088 node = calloc(1, sizeof(*node));
1089 if (!node)
1090 return -ENOMEM;
1091
1092 *cursor->last = node;
1093 }
1094
1095 node->ip = ip;
1096 map_symbol__exit(ms: &node->ms);
1097 node->ms = *ms;
1098 node->ms.maps = maps__get(maps: ms->maps);
1099 node->ms.map = map__get(map: ms->map);
1100 node->branch = branch;
1101 node->nr_loop_iter = nr_loop_iter;
1102 node->iter_cycles = iter_cycles;
1103 node->srcline = srcline;
1104
1105 if (flags)
1106 memcpy(&node->branch_flags, flags,
1107 sizeof(struct branch_flags));
1108
1109 node->branch_from = branch_from;
1110 cursor->nr++;
1111
1112 cursor->last = &node->next;
1113
1114 return 0;
1115}
1116
1117int sample__resolve_callchain(struct perf_sample *sample,
1118 struct callchain_cursor *cursor, struct symbol **parent,
1119 struct evsel *evsel, struct addr_location *al,
1120 int max_stack)
1121{
1122 if (sample->callchain == NULL && !symbol_conf.show_branchflag_count)
1123 return 0;
1124
1125 if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain ||
1126 perf_hpp_list.parent || symbol_conf.show_branchflag_count) {
1127 return thread__resolve_callchain(thread: al->thread, cursor, evsel, sample,
1128 parent, root_al: al, max_stack);
1129 }
1130 return 0;
1131}
1132
1133int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample)
1134{
1135 if ((!symbol_conf.use_callchain || sample->callchain == NULL) &&
1136 !symbol_conf.show_branchflag_count)
1137 return 0;
1138 return callchain_append(root: he->callchain, cursor: get_tls_callchain_cursor(), period: sample->period);
1139}
1140
1141int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
1142 bool hide_unresolved)
1143{
1144 struct machine *machine = maps__machine(maps: node->ms.maps);
1145
1146 maps__put(maps: al->maps);
1147 al->maps = maps__get(maps: node->ms.maps);
1148 map__put(map: al->map);
1149 al->map = map__get(map: node->ms.map);
1150 al->sym = node->ms.sym;
1151 al->srcline = node->srcline;
1152 al->addr = node->ip;
1153
1154 if (al->sym == NULL) {
1155 if (hide_unresolved)
1156 return 0;
1157 if (al->map == NULL)
1158 goto out;
1159 }
1160 if (maps__equal(a: al->maps, b: machine__kernel_maps(machine))) {
1161 if (machine__is_host(machine)) {
1162 al->cpumode = PERF_RECORD_MISC_KERNEL;
1163 al->level = 'k';
1164 } else {
1165 al->cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
1166 al->level = 'g';
1167 }
1168 } else {
1169 if (machine__is_host(machine)) {
1170 al->cpumode = PERF_RECORD_MISC_USER;
1171 al->level = '.';
1172 } else if (perf_guest) {
1173 al->cpumode = PERF_RECORD_MISC_GUEST_USER;
1174 al->level = 'u';
1175 } else {
1176 al->cpumode = PERF_RECORD_MISC_HYPERVISOR;
1177 al->level = 'H';
1178 }
1179 }
1180
1181out:
1182 return 1;
1183}
1184
1185char *callchain_list__sym_name(struct callchain_list *cl,
1186 char *bf, size_t bfsize, bool show_dso)
1187{
1188 bool show_addr = callchain_param.key == CCKEY_ADDRESS;
1189 bool show_srcline = show_addr || callchain_param.key == CCKEY_SRCLINE;
1190 int printed;
1191
1192 if (cl->ms.sym) {
1193 const char *inlined = cl->ms.sym->inlined ? " (inlined)" : "";
1194
1195 if (show_srcline && cl->srcline)
1196 printed = scnprintf(buf: bf, size: bfsize, fmt: "%s %s%s",
1197 cl->ms.sym->name, cl->srcline,
1198 inlined);
1199 else
1200 printed = scnprintf(buf: bf, size: bfsize, fmt: "%s%s",
1201 cl->ms.sym->name, inlined);
1202 } else
1203 printed = scnprintf(bf, bfsize, "%#" PRIx64, cl->ip);
1204
1205 if (show_dso)
1206 scnprintf(buf: bf + printed, size: bfsize - printed, fmt: " %s",
1207 cl->ms.map ?
1208 map__dso(map: cl->ms.map)->short_name :
1209 "unknown");
1210
1211 return bf;
1212}
1213
1214char *callchain_node__scnprintf_value(struct callchain_node *node,
1215 char *bf, size_t bfsize, u64 total)
1216{
1217 double percent = 0.0;
1218 u64 period = callchain_cumul_hits(node);
1219 unsigned count = callchain_cumul_counts(node);
1220
1221 if (callchain_param.mode == CHAIN_FOLDED) {
1222 period = node->hit;
1223 count = node->count;
1224 }
1225
1226 switch (callchain_param.value) {
1227 case CCVAL_PERIOD:
1228 scnprintf(bf, bfsize, "%"PRIu64, period);
1229 break;
1230 case CCVAL_COUNT:
1231 scnprintf(buf: bf, size: bfsize, fmt: "%u", count);
1232 break;
1233 case CCVAL_PERCENT:
1234 default:
1235 if (total)
1236 percent = period * 100.0 / total;
1237 scnprintf(buf: bf, size: bfsize, fmt: "%.2f%%", percent);
1238 break;
1239 }
1240 return bf;
1241}
1242
1243int callchain_node__fprintf_value(struct callchain_node *node,
1244 FILE *fp, u64 total)
1245{
1246 double percent = 0.0;
1247 u64 period = callchain_cumul_hits(node);
1248 unsigned count = callchain_cumul_counts(node);
1249
1250 if (callchain_param.mode == CHAIN_FOLDED) {
1251 period = node->hit;
1252 count = node->count;
1253 }
1254
1255 switch (callchain_param.value) {
1256 case CCVAL_PERIOD:
1257 return fprintf(fp, "%"PRIu64, period);
1258 case CCVAL_COUNT:
1259 return fprintf(fp, "%u", count);
1260 case CCVAL_PERCENT:
1261 default:
1262 if (total)
1263 percent = period * 100.0 / total;
1264 return percent_color_fprintf(fp, "%.2f%%", percent);
1265 }
1266 return 0;
1267}
1268
1269static void callchain_counts_value(struct callchain_node *node,
1270 u64 *branch_count, u64 *predicted_count,
1271 u64 *abort_count, u64 *cycles_count)
1272{
1273 struct callchain_list *clist;
1274
1275 list_for_each_entry(clist, &node->val, list) {
1276 if (branch_count)
1277 *branch_count += clist->branch_count;
1278
1279 if (predicted_count)
1280 *predicted_count += clist->predicted_count;
1281
1282 if (abort_count)
1283 *abort_count += clist->abort_count;
1284
1285 if (cycles_count)
1286 *cycles_count += clist->cycles_count;
1287 }
1288}
1289
1290static int callchain_node_branch_counts_cumul(struct callchain_node *node,
1291 u64 *branch_count,
1292 u64 *predicted_count,
1293 u64 *abort_count,
1294 u64 *cycles_count)
1295{
1296 struct callchain_node *child;
1297 struct rb_node *n;
1298
1299 n = rb_first(&node->rb_root_in);
1300 while (n) {
1301 child = rb_entry(n, struct callchain_node, rb_node_in);
1302 n = rb_next(n);
1303
1304 callchain_node_branch_counts_cumul(node: child, branch_count,
1305 predicted_count,
1306 abort_count,
1307 cycles_count);
1308
1309 callchain_counts_value(node: child, branch_count,
1310 predicted_count, abort_count,
1311 cycles_count);
1312 }
1313
1314 return 0;
1315}
1316
1317int callchain_branch_counts(struct callchain_root *root,
1318 u64 *branch_count, u64 *predicted_count,
1319 u64 *abort_count, u64 *cycles_count)
1320{
1321 if (branch_count)
1322 *branch_count = 0;
1323
1324 if (predicted_count)
1325 *predicted_count = 0;
1326
1327 if (abort_count)
1328 *abort_count = 0;
1329
1330 if (cycles_count)
1331 *cycles_count = 0;
1332
1333 return callchain_node_branch_counts_cumul(node: &root->node,
1334 branch_count,
1335 predicted_count,
1336 abort_count,
1337 cycles_count);
1338}
1339
1340static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int bfsize)
1341{
1342 return scnprintf(bf, bfsize, "%s%s:%" PRId64 "", (idx) ? " " : " (", str, value);
1343}
1344
1345static int count_float_printf(int idx, const char *str, float value,
1346 char *bf, int bfsize, float threshold)
1347{
1348 if (threshold != 0.0 && value < threshold)
1349 return 0;
1350
1351 return scnprintf(buf: bf, size: bfsize, fmt: "%s%s:%.1f%%", (idx) ? " " : " (", str, value);
1352}
1353
1354static int branch_to_str(char *bf, int bfsize,
1355 u64 branch_count, u64 predicted_count,
1356 u64 abort_count,
1357 const struct branch_type_stat *brtype_stat)
1358{
1359 int printed, i = 0;
1360
1361 printed = branch_type_str(st: brtype_stat, bf, bfsize);
1362 if (printed)
1363 i++;
1364
1365 if (predicted_count < branch_count) {
1366 printed += count_float_printf(idx: i++, str: "predicted",
1367 value: predicted_count * 100.0 / branch_count,
1368 bf: bf + printed, bfsize: bfsize - printed, threshold: 0.0);
1369 }
1370
1371 if (abort_count) {
1372 printed += count_float_printf(idx: i++, str: "abort",
1373 value: abort_count * 100.0 / branch_count,
1374 bf: bf + printed, bfsize: bfsize - printed, threshold: 0.1);
1375 }
1376
1377 if (i)
1378 printed += scnprintf(buf: bf + printed, size: bfsize - printed, fmt: ")");
1379
1380 return printed;
1381}
1382
1383static int branch_from_str(char *bf, int bfsize,
1384 u64 branch_count,
1385 u64 cycles_count, u64 iter_count,
1386 u64 iter_cycles, u64 from_count)
1387{
1388 int printed = 0, i = 0;
1389 u64 cycles, v = 0;
1390
1391 cycles = cycles_count / branch_count;
1392 if (cycles) {
1393 printed += count_pri64_printf(idx: i++, str: "cycles",
1394 value: cycles,
1395 bf: bf + printed, bfsize: bfsize - printed);
1396 }
1397
1398 if (iter_count && from_count) {
1399 v = iter_count / from_count;
1400 if (v) {
1401 printed += count_pri64_printf(idx: i++, str: "iter",
1402 value: v, bf: bf + printed, bfsize: bfsize - printed);
1403
1404 printed += count_pri64_printf(idx: i++, str: "avg_cycles",
1405 value: iter_cycles / iter_count,
1406 bf: bf + printed, bfsize: bfsize - printed);
1407 }
1408 }
1409
1410 if (i)
1411 printed += scnprintf(buf: bf + printed, size: bfsize - printed, fmt: ")");
1412
1413 return printed;
1414}
1415
1416static int counts_str_build(char *bf, int bfsize,
1417 u64 branch_count, u64 predicted_count,
1418 u64 abort_count, u64 cycles_count,
1419 u64 iter_count, u64 iter_cycles,
1420 u64 from_count,
1421 const struct branch_type_stat *brtype_stat)
1422{
1423 int printed;
1424
1425 if (branch_count == 0)
1426 return scnprintf(buf: bf, size: bfsize, fmt: " (calltrace)");
1427
1428 if (brtype_stat->branch_to) {
1429 printed = branch_to_str(bf, bfsize, branch_count,
1430 predicted_count, abort_count, brtype_stat);
1431 } else {
1432 printed = branch_from_str(bf, bfsize, branch_count,
1433 cycles_count, iter_count, iter_cycles,
1434 from_count);
1435 }
1436
1437 if (!printed)
1438 bf[0] = 0;
1439
1440 return printed;
1441}
1442
1443static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
1444 u64 branch_count, u64 predicted_count,
1445 u64 abort_count, u64 cycles_count,
1446 u64 iter_count, u64 iter_cycles,
1447 u64 from_count,
1448 const struct branch_type_stat *brtype_stat)
1449{
1450 char str[256];
1451
1452 counts_str_build(bf: str, bfsize: sizeof(str), branch_count,
1453 predicted_count, abort_count, cycles_count,
1454 iter_count, iter_cycles, from_count, brtype_stat);
1455
1456 if (fp)
1457 return fprintf(fp, "%s", str);
1458
1459 return scnprintf(buf: bf, size: bfsize, fmt: "%s", str);
1460}
1461
1462int callchain_list_counts__printf_value(struct callchain_list *clist,
1463 FILE *fp, char *bf, int bfsize)
1464{
1465 static const struct branch_type_stat empty_brtype_stat = {};
1466 const struct branch_type_stat *brtype_stat;
1467 u64 branch_count, predicted_count;
1468 u64 abort_count, cycles_count;
1469 u64 iter_count, iter_cycles;
1470 u64 from_count;
1471
1472 brtype_stat = clist->brtype_stat ?: &empty_brtype_stat;
1473 branch_count = clist->branch_count;
1474 predicted_count = clist->predicted_count;
1475 abort_count = clist->abort_count;
1476 cycles_count = clist->cycles_count;
1477 iter_count = clist->iter_count;
1478 iter_cycles = clist->iter_cycles;
1479 from_count = clist->from_count;
1480
1481 return callchain_counts_printf(fp, bf, bfsize, branch_count,
1482 predicted_count, abort_count,
1483 cycles_count, iter_count, iter_cycles,
1484 from_count, brtype_stat);
1485}
1486
1487static void free_callchain_node(struct callchain_node *node)
1488{
1489 struct callchain_list *list, *tmp;
1490 struct callchain_node *child;
1491 struct rb_node *n;
1492
1493 list_for_each_entry_safe(list, tmp, &node->parent_val, list) {
1494 list_del_init(entry: &list->list);
1495 map_symbol__exit(ms: &list->ms);
1496 zfree(&list->brtype_stat);
1497 free(list);
1498 }
1499
1500 list_for_each_entry_safe(list, tmp, &node->val, list) {
1501 list_del_init(entry: &list->list);
1502 map_symbol__exit(ms: &list->ms);
1503 zfree(&list->brtype_stat);
1504 free(list);
1505 }
1506
1507 n = rb_first(&node->rb_root_in);
1508 while (n) {
1509 child = container_of(n, struct callchain_node, rb_node_in);
1510 n = rb_next(n);
1511 rb_erase(&child->rb_node_in, &node->rb_root_in);
1512
1513 free_callchain_node(node: child);
1514 free(child);
1515 }
1516}
1517
1518void free_callchain(struct callchain_root *root)
1519{
1520 if (!symbol_conf.use_callchain)
1521 return;
1522
1523 free_callchain_node(node: &root->node);
1524}
1525
1526static u64 decay_callchain_node(struct callchain_node *node)
1527{
1528 struct callchain_node *child;
1529 struct rb_node *n;
1530 u64 child_hits = 0;
1531
1532 n = rb_first(&node->rb_root_in);
1533 while (n) {
1534 child = container_of(n, struct callchain_node, rb_node_in);
1535
1536 child_hits += decay_callchain_node(node: child);
1537 n = rb_next(n);
1538 }
1539
1540 node->hit = (node->hit * 7) / 8;
1541 node->children_hit = child_hits;
1542
1543 return node->hit;
1544}
1545
1546void decay_callchain(struct callchain_root *root)
1547{
1548 if (!symbol_conf.use_callchain)
1549 return;
1550
1551 decay_callchain_node(node: &root->node);
1552}
1553
1554int callchain_node__make_parent_list(struct callchain_node *node)
1555{
1556 struct callchain_node *parent = node->parent;
1557 struct callchain_list *chain, *new;
1558 LIST_HEAD(head);
1559
1560 while (parent) {
1561 list_for_each_entry_reverse(chain, &parent->val, list) {
1562 new = malloc(sizeof(*new));
1563 if (new == NULL)
1564 goto out;
1565 *new = *chain;
1566 new->has_children = false;
1567 new->ms.map = map__get(map: new->ms.map);
1568 list_add_tail(new: &new->list, head: &head);
1569 }
1570 parent = parent->parent;
1571 }
1572
1573 list_for_each_entry_safe_reverse(chain, new, &head, list)
1574 list_move_tail(list: &chain->list, head: &node->parent_val);
1575
1576 if (!list_empty(head: &node->parent_val)) {
1577 chain = list_first_entry(&node->parent_val, struct callchain_list, list);
1578 chain->has_children = rb_prev(&node->rb_node) || rb_next(&node->rb_node);
1579
1580 chain = list_first_entry(&node->val, struct callchain_list, list);
1581 chain->has_children = false;
1582 }
1583 return 0;
1584
1585out:
1586 list_for_each_entry_safe(chain, new, &head, list) {
1587 list_del_init(entry: &chain->list);
1588 map_symbol__exit(ms: &chain->ms);
1589 zfree(&chain->brtype_stat);
1590 free(chain);
1591 }
1592 return -ENOMEM;
1593}
1594
1595static void callchain_cursor__delete(void *vcursor)
1596{
1597 struct callchain_cursor *cursor = vcursor;
1598 struct callchain_cursor_node *node, *next;
1599
1600 callchain_cursor_reset(cursor);
1601 for (node = cursor->first; node != NULL; node = next) {
1602 next = node->next;
1603 free(node);
1604 }
1605 free(cursor);
1606}
1607
1608static void init_callchain_cursor_key(void)
1609{
1610 if (pthread_key_create(&callchain_cursor, callchain_cursor__delete)) {
1611 pr_err("callchain cursor creation failed");
1612 abort();
1613 }
1614}
1615
1616struct callchain_cursor *get_tls_callchain_cursor(void)
1617{
1618 static pthread_once_t once_control = PTHREAD_ONCE_INIT;
1619 struct callchain_cursor *cursor;
1620
1621 pthread_once(&once_control, init_callchain_cursor_key);
1622 cursor = pthread_getspecific(callchain_cursor);
1623 if (!cursor) {
1624 cursor = zalloc(sizeof(*cursor));
1625 if (!cursor)
1626 pr_debug3("%s: not enough memory\n", __func__);
1627 pthread_setspecific(callchain_cursor, cursor);
1628 }
1629 return cursor;
1630}
1631
1632int callchain_cursor__copy(struct callchain_cursor *dst,
1633 struct callchain_cursor *src)
1634{
1635 int rc = 0;
1636
1637 callchain_cursor_reset(cursor: dst);
1638 callchain_cursor_commit(cursor: src);
1639
1640 while (true) {
1641 struct callchain_cursor_node *node;
1642
1643 node = callchain_cursor_current(cursor: src);
1644 if (node == NULL)
1645 break;
1646
1647 rc = callchain_cursor_append(cursor: dst, ip: node->ip, ms: &node->ms,
1648 branch: node->branch, flags: &node->branch_flags,
1649 nr_loop_iter: node->nr_loop_iter,
1650 iter_cycles: node->iter_cycles,
1651 branch_from: node->branch_from, srcline: node->srcline);
1652 if (rc)
1653 break;
1654
1655 callchain_cursor_advance(cursor: src);
1656 }
1657
1658 return rc;
1659}
1660
1661/*
1662 * Initialize a cursor before adding entries inside, but keep
1663 * the previously allocated entries as a cache.
1664 */
1665void callchain_cursor_reset(struct callchain_cursor *cursor)
1666{
1667 struct callchain_cursor_node *node;
1668
1669 cursor->nr = 0;
1670 cursor->last = &cursor->first;
1671
1672 for (node = cursor->first; node != NULL; node = node->next)
1673 map_symbol__exit(ms: &node->ms);
1674}
1675
1676void callchain_param_setup(u64 sample_type, const char *arch)
1677{
1678 if (symbol_conf.use_callchain || symbol_conf.cumulate_callchain) {
1679 if ((sample_type & PERF_SAMPLE_REGS_USER) &&
1680 (sample_type & PERF_SAMPLE_STACK_USER)) {
1681 callchain_param.record_mode = CALLCHAIN_DWARF;
1682 dwarf_callchain_users = true;
1683 } else if (sample_type & PERF_SAMPLE_BRANCH_STACK)
1684 callchain_param.record_mode = CALLCHAIN_LBR;
1685 else
1686 callchain_param.record_mode = CALLCHAIN_FP;
1687 }
1688
1689 /*
1690 * It's necessary to use libunwind to reliably determine the caller of
1691 * a leaf function on aarch64, as otherwise we cannot know whether to
1692 * start from the LR or FP.
1693 *
1694 * Always starting from the LR can result in duplicate or entirely
1695 * erroneous entries. Always skipping the LR and starting from the FP
1696 * can result in missing entries.
1697 */
1698 if (callchain_param.record_mode == CALLCHAIN_FP && !strcmp(arch, "arm64"))
1699 dwarf_callchain_users = true;
1700}
1701
1702static bool chain_match(struct callchain_list *base_chain,
1703 struct callchain_list *pair_chain)
1704{
1705 enum match_result match;
1706
1707 match = match_chain_strings(left: base_chain->srcline,
1708 right: pair_chain->srcline);
1709 if (match != MATCH_ERROR)
1710 return match == MATCH_EQ;
1711
1712 match = match_chain_dso_addresses(left_map: base_chain->ms.map,
1713 left_ip: base_chain->ip,
1714 right_map: pair_chain->ms.map,
1715 right_ip: pair_chain->ip);
1716
1717 return match == MATCH_EQ;
1718}
1719
1720bool callchain_cnode_matched(struct callchain_node *base_cnode,
1721 struct callchain_node *pair_cnode)
1722{
1723 struct callchain_list *base_chain, *pair_chain;
1724 bool match = false;
1725
1726 pair_chain = list_first_entry(&pair_cnode->val,
1727 struct callchain_list,
1728 list);
1729
1730 list_for_each_entry(base_chain, &base_cnode->val, list) {
1731 if (&pair_chain->list == &pair_cnode->val)
1732 return false;
1733
1734 if (!base_chain->srcline || !pair_chain->srcline) {
1735 pair_chain = list_next_entry(pair_chain, list);
1736 continue;
1737 }
1738
1739 match = chain_match(base_chain, pair_chain);
1740 if (!match)
1741 return false;
1742
1743 pair_chain = list_next_entry(pair_chain, list);
1744 }
1745
1746 /*
1747 * Say chain1 is ABC, chain2 is ABCD, we consider they are
1748 * not fully matched.
1749 */
1750 if (pair_chain && (&pair_chain->list != &pair_cnode->val))
1751 return false;
1752
1753 return match;
1754}
1755
1756static u64 count_callchain_hits(struct hist_entry *he)
1757{
1758 struct rb_root *root = &he->sorted_chain;
1759 struct rb_node *rb_node = rb_first(root);
1760 struct callchain_node *node;
1761 u64 chain_hits = 0;
1762
1763 while (rb_node) {
1764 node = rb_entry(rb_node, struct callchain_node, rb_node);
1765 chain_hits += node->hit;
1766 rb_node = rb_next(rb_node);
1767 }
1768
1769 return chain_hits;
1770}
1771
1772u64 callchain_total_hits(struct hists *hists)
1773{
1774 struct rb_node *next = rb_first_cached(&hists->entries);
1775 u64 chain_hits = 0;
1776
1777 while (next) {
1778 struct hist_entry *he = rb_entry(next, struct hist_entry,
1779 rb_node);
1780
1781 chain_hits += count_callchain_hits(he);
1782 next = rb_next(&he->rb_node);
1783 }
1784
1785 return chain_hits;
1786}
1787
1788s64 callchain_avg_cycles(struct callchain_node *cnode)
1789{
1790 struct callchain_list *chain;
1791 s64 cycles = 0;
1792
1793 list_for_each_entry(chain, &cnode->val, list) {
1794 if (chain->srcline && chain->branch_count)
1795 cycles += chain->cycles_count / chain->branch_count;
1796 }
1797
1798 return cycles;
1799}
1800

source code of linux/tools/perf/util/callchain.c