1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * build-id.c
4 *
5 * build-id support
6 *
7 * Copyright (C) 2009, 2010 Red Hat Inc.
8 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
9 */
10 #include "util.h" // lsdir(), mkdir_p(), rm_rf()
11 #include <dirent.h>
12 #include <errno.h>
13 #include <stdio.h>
14 #include <sys/stat.h>
15 #include <sys/types.h>
16 #include "util/copyfile.h"
17 #include "dso.h"
18 #include "build-id.h"
19 #include "event.h"
20 #include "namespaces.h"
21 #include "map.h"
22 #include "symbol.h"
23 #include "thread.h"
24 #include <linux/kernel.h>
25 #include "debug.h"
26 #include "session.h"
27 #include "tool.h"
28 #include "header.h"
29 #include "vdso.h"
30 #include "path.h"
31 #include "probe-file.h"
32 #include "strlist.h"
33
34 #ifdef HAVE_DEBUGINFOD_SUPPORT
35 #include <elfutils/debuginfod.h>
36 #endif
37
38 #include <linux/ctype.h>
39 #include <linux/zalloc.h>
40 #include <linux/string.h>
41 #include <asm/bug.h>
42
43 static bool no_buildid_cache;
44
45 int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
46 union perf_event *event,
47 struct perf_sample *sample,
48 struct evsel *evsel __maybe_unused,
49 struct machine *machine)
50 {
51 struct addr_location al;
52 struct thread *thread = machine__findnew_thread(machine, sample->pid,
53 sample->tid);
54
55 if (thread == NULL) {
56 pr_err("problem processing %d event, skipping it.\n",
57 event->header.type);
58 return -1;
59 }
60
61 addr_location__init(&al);
62 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
63 dso__set_hit(map__dso(al.map));
64
65 addr_location__exit(&al);
66 thread__put(thread);
67 return 0;
68 }
69
70 static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
71 union perf_event *event,
72 struct perf_sample *sample
73 __maybe_unused,
74 struct machine *machine)
75 {
76 struct thread *thread = machine__findnew_thread(machine,
77 event->fork.pid,
78 event->fork.tid);
79
80 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
81 event->fork.ppid, event->fork.ptid);
82
83 if (thread) {
84 machine__remove_thread(machine, thread);
85 thread__put(thread);
86 }
87
88 return 0;
89 }
90
91 struct perf_tool build_id__mark_dso_hit_ops = {
92 .sample = build_id__mark_dso_hit,
93 .mmap = perf_event__process_mmap,
94 .mmap2 = perf_event__process_mmap2,
95 .fork = perf_event__process_fork,
96 .exit = perf_event__exit_del_thread,
97 .attr = perf_event__process_attr,
98 .build_id = perf_event__process_build_id,
99 .ordered_events = true,
100 };
101
102 int build_id__sprintf(const struct build_id *build_id, char *bf)
103 {
104 char *bid = bf;
105 const u8 *raw = build_id->data;
106 size_t i;
107
108 bf[0] = 0x0;
109
110 for (i = 0; i < build_id->size; ++i) {
111 sprintf(bid, "%02x", *raw);
112 ++raw;
113 bid += 2;
114 }
115
116 return (bid - bf) + 1;
117 }
118
119 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
120 {
121 char notes[PATH_MAX];
122 struct build_id bid;
123 int ret;
124
125 if (!root_dir)
126 root_dir = "";
127
128 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
129
130 ret = sysfs__read_build_id(notes, &bid);
131 if (ret < 0)
132 return ret;
133
134 return build_id__sprintf(&bid, sbuild_id);
135 }
136
137 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
138 {
139 struct build_id bid;
140 int ret;
141
142 ret = filename__read_build_id(pathname, &bid);
143 if (ret < 0)
144 return ret;
145
146 return build_id__sprintf(&bid, sbuild_id);
147 }
148
149 /* asnprintf consolidates asprintf and snprintf */
150 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
151 {
152 va_list ap;
153 int ret;
154
155 if (!strp)
156 return -EINVAL;
157
158 va_start(ap, fmt);
159 if (*strp)
160 ret = vsnprintf(*strp, size, fmt, ap);
161 else
162 ret = vasprintf(strp, fmt, ap);
163 va_end(ap);
164
165 return ret;
166 }
167
168 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
169 size_t size)
170 {
171 bool retry_old = true;
172
173 snprintf(bf, size, "%s/%s/%s/kallsyms",
174 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
175 retry:
176 if (!access(bf, F_OK))
177 return bf;
178 if (retry_old) {
179 /* Try old style kallsyms cache */
180 snprintf(bf, size, "%s/%s/%s",
181 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
182 retry_old = false;
183 goto retry;
184 }
185
186 return NULL;
187 }
188
189 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
190 {
191 char *tmp = bf;
192 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
193 sbuild_id, sbuild_id + 2);
194 if (ret < 0 || (tmp && size < (unsigned int)ret))
195 return NULL;
196 return bf;
197 }
198
199 /* The caller is responsible to free the returned buffer. */
200 char *build_id_cache__origname(const char *sbuild_id)
201 {
202 char *linkname;
203 char buf[PATH_MAX];
204 char *ret = NULL, *p;
205 size_t offs = 5; /* == strlen("../..") */
206 ssize_t len;
207
208 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
209 if (!linkname)
210 return NULL;
211
212 len = readlink(linkname, buf, sizeof(buf) - 1);
213 if (len <= 0)
214 goto out;
215 buf[len] = '\0';
216
217 /* The link should be "../..<origpath>/<sbuild_id>" */
218 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
219 if (p && (p > buf + offs)) {
220 *p = '\0';
221 if (buf[offs + 1] == '[')
222 offs++; /*
223 * This is a DSO name, like [kernel.kallsyms].
224 * Skip the first '/', since this is not the
225 * cache of a regular file.
226 */
227 ret = strdup(buf + offs); /* Skip "../..[/]" */
228 }
229 out:
230 free(linkname);
231 return ret;
232 }
233
234 /* Check if the given build_id cache is valid on current running system */
235 static bool build_id_cache__valid_id(char *sbuild_id)
236 {
237 char real_sbuild_id[SBUILD_ID_SIZE] = "";
238 char *pathname;
239 int ret = 0;
240 bool result = false;
241
242 pathname = build_id_cache__origname(sbuild_id);
243 if (!pathname)
244 return false;
245
246 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
247 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
248 else if (pathname[0] == '/')
249 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
250 else
251 ret = -EINVAL; /* Should we support other special DSO cache? */
252 if (ret >= 0)
253 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
254 free(pathname);
255
256 return result;
257 }
258
259 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
260 bool is_debug)
261 {
262 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
263 "debug" : "elf"));
264 }
265
266 char *__dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
267 bool is_debug, bool is_kallsyms)
268 {
269 bool is_vdso = dso__is_vdso((struct dso *)dso);
270 char sbuild_id[SBUILD_ID_SIZE];
271 char *linkname;
272 bool alloc = (bf == NULL);
273 int ret;
274
275 if (!dso__has_build_id(dso))
276 return NULL;
277
278 build_id__sprintf(dso__bid_const(dso), sbuild_id);
279 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
280 if (!linkname)
281 return NULL;
282
283 /* Check if old style build_id cache */
284 if (is_regular_file(linkname))
285 ret = asnprintf(&bf, size, "%s", linkname);
286 else
287 ret = asnprintf(&bf, size, "%s/%s", linkname,
288 build_id_cache__basename(is_kallsyms, is_vdso,
289 is_debug));
290 if (ret < 0 || (!alloc && size < (unsigned int)ret))
291 bf = NULL;
292 free(linkname);
293
294 return bf;
295 }
296
297 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
298 bool is_debug)
299 {
300 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
301
302 return __dso__build_id_filename(dso, bf, size, is_debug, is_kallsyms);
303 }
304
305 static int write_buildid(const char *name, size_t name_len, struct build_id *bid,
306 pid_t pid, u16 misc, struct feat_fd *fd)
307 {
308 int err;
309 struct perf_record_header_build_id b;
310 size_t len;
311
312 len = name_len + 1;
313 len = PERF_ALIGN(len, NAME_ALIGN);
314
315 memset(&b, 0, sizeof(b));
316 memcpy(&b.data, bid->data, bid->size);
317 b.size = (u8) bid->size;
318 misc |= PERF_RECORD_MISC_BUILD_ID_SIZE;
319 b.pid = pid;
320 b.header.misc = misc;
321 b.header.size = sizeof(b) + len;
322
323 err = do_write(fd, &b, sizeof(b));
324 if (err < 0)
325 return err;
326
327 return write_padded(fd, name, name_len + 1, len);
328 }
329
330 struct machine__write_buildid_table_cb_args {
331 struct machine *machine;
332 struct feat_fd *fd;
333 u16 kmisc, umisc;
334 };
335
336 static int machine__write_buildid_table_cb(struct dso *dso, void *data)
337 {
338 struct machine__write_buildid_table_cb_args *args = data;
339 const char *name;
340 size_t name_len;
341 bool in_kernel = false;
342
343 if (!dso__has_build_id(dso))
344 return 0;
345
346 if (!dso__hit(dso) && !dso__is_vdso(dso))
347 return 0;
348
349 if (dso__is_vdso(dso)) {
350 name = dso__short_name(dso);
351 name_len = dso__short_name_len(dso);
352 } else if (dso__is_kcore(dso)) {
353 name = args->machine->mmap_name;
354 name_len = strlen(name);
355 } else {
356 name = dso__long_name(dso);
357 name_len = dso__long_name_len(dso);
358 }
359
360 in_kernel = dso__kernel(dso) || is_kernel_module(name, PERF_RECORD_MISC_CPUMODE_UNKNOWN);
361 return write_buildid(name, name_len, dso__bid(dso), args->machine->pid,
362 in_kernel ? args->kmisc : args->umisc, args->fd);
363 }
364
365 static int machine__write_buildid_table(struct machine *machine, struct feat_fd *fd)
366 {
367 struct machine__write_buildid_table_cb_args args = {
368 .machine = machine,
369 .fd = fd,
370 .kmisc = PERF_RECORD_MISC_KERNEL,
371 .umisc = PERF_RECORD_MISC_USER,
372 };
373
374 if (!machine__is_host(machine)) {
375 args.kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
376 args.umisc = PERF_RECORD_MISC_GUEST_USER;
377 }
378
379 return dsos__for_each_dso(&machine->dsos, machine__write_buildid_table_cb, &args);
380 }
381
382 int perf_session__write_buildid_table(struct perf_session *session,
383 struct feat_fd *fd)
384 {
385 struct rb_node *nd;
386 int err = machine__write_buildid_table(&session->machines.host, fd);
387
388 if (err)
389 return err;
390
391 for (nd = rb_first_cached(&session->machines.guests); nd;
392 nd = rb_next(nd)) {
393 struct machine *pos = rb_entry(nd, struct machine, rb_node);
394 err = machine__write_buildid_table(pos, fd);
395 if (err)
396 break;
397 }
398 return err;
399 }
400
401 void disable_buildid_cache(void)
402 {
403 no_buildid_cache = true;
404 }
405
406 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
407 struct dirent *d)
408 {
409 return (strlen(d->d_name) == 2) &&
410 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
411 }
412
413 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
414 struct dirent *d)
415 {
416 int i = 0;
417 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
418 i++;
419 return (i >= SBUILD_ID_MIN_SIZE - 3) && (i <= SBUILD_ID_SIZE - 3) &&
420 (d->d_name[i] == '\0');
421 }
422
423 struct strlist *build_id_cache__list_all(bool validonly)
424 {
425 struct strlist *toplist, *linklist = NULL, *bidlist;
426 struct str_node *nd, *nd2;
427 char *topdir, *linkdir = NULL;
428 char sbuild_id[SBUILD_ID_SIZE];
429
430 /* for filename__ functions */
431 if (validonly)
432 symbol__init(NULL);
433
434 /* Open the top-level directory */
435 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
436 return NULL;
437
438 bidlist = strlist__new(NULL, NULL);
439 if (!bidlist)
440 goto out;
441
442 toplist = lsdir(topdir, lsdir_bid_head_filter);
443 if (!toplist) {
444 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
445 /* If there is no buildid cache, return an empty list */
446 if (errno == ENOENT)
447 goto out;
448 goto err_out;
449 }
450
451 strlist__for_each_entry(nd, toplist) {
452 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
453 goto err_out;
454 /* Open the lower-level directory */
455 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
456 if (!linklist) {
457 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
458 goto err_out;
459 }
460 strlist__for_each_entry(nd2, linklist) {
461 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
462 nd->s, nd2->s) > SBUILD_ID_SIZE - 1)
463 goto err_out;
464 if (validonly && !build_id_cache__valid_id(sbuild_id))
465 continue;
466 if (strlist__add(bidlist, sbuild_id) < 0)
467 goto err_out;
468 }
469 strlist__delete(linklist);
470 zfree(&linkdir);
471 }
472
473 out_free:
474 strlist__delete(toplist);
475 out:
476 free(topdir);
477
478 return bidlist;
479
480 err_out:
481 strlist__delete(linklist);
482 zfree(&linkdir);
483 strlist__delete(bidlist);
484 bidlist = NULL;
485 goto out_free;
486 }
487
488 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
489 {
490 size_t i;
491
492 for (i = 0; i < len; i++) {
493 if (!isxdigit(maybe_sbuild_id[i]))
494 return false;
495 }
496 return true;
497 }
498
499 /* Return the valid complete build-id */
500 char *build_id_cache__complement(const char *incomplete_sbuild_id)
501 {
502 struct strlist *bidlist;
503 struct str_node *nd, *cand = NULL;
504 char *sbuild_id = NULL;
505 size_t len = strlen(incomplete_sbuild_id);
506
507 if (len >= SBUILD_ID_SIZE ||
508 !str_is_build_id(incomplete_sbuild_id, len))
509 return NULL;
510
511 bidlist = build_id_cache__list_all(true);
512 if (!bidlist)
513 return NULL;
514
515 strlist__for_each_entry(nd, bidlist) {
516 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
517 continue;
518 if (cand) { /* Error: There are more than 2 candidates. */
519 cand = NULL;
520 break;
521 }
522 cand = nd;
523 }
524 if (cand)
525 sbuild_id = strdup(cand->s);
526 strlist__delete(bidlist);
527
528 return sbuild_id;
529 }
530
531 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
532 struct nsinfo *nsi, bool is_kallsyms,
533 bool is_vdso)
534 {
535 char *realname = NULL, *filename;
536 bool slash = is_kallsyms || is_vdso;
537
538 if (!slash)
539 realname = nsinfo__realpath(name, nsi);
540
541 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
542 is_vdso ? DSO__NAME_VDSO : (realname ? realname : name),
543 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
544 filename = NULL;
545
546 free(realname);
547 return filename;
548 }
549
550 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
551 struct strlist **result)
552 {
553 char *dir_name;
554 int ret = 0;
555
556 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
557 if (!dir_name)
558 return -ENOMEM;
559
560 *result = lsdir(dir_name, lsdir_no_dot_filter);
561 if (!*result)
562 ret = -errno;
563 free(dir_name);
564
565 return ret;
566 }
567
568 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
569 static int build_id_cache__add_sdt_cache(const char *sbuild_id,
570 const char *realname,
571 struct nsinfo *nsi)
572 {
573 struct probe_cache *cache;
574 int ret;
575 struct nscookie nsc;
576
577 cache = probe_cache__new(sbuild_id, nsi);
578 if (!cache)
579 return -1;
580
581 nsinfo__mountns_enter(nsi, &nsc);
582 ret = probe_cache__scan_sdt(cache, realname);
583 nsinfo__mountns_exit(&nsc);
584 if (ret >= 0) {
585 pr_debug4("Found %d SDTs in %s\n", ret, realname);
586 if (probe_cache__commit(cache) < 0)
587 ret = -1;
588 }
589 probe_cache__delete(cache);
590 return ret;
591 }
592 #else
593 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
594 #endif
595
596 static char *build_id_cache__find_debug(const char *sbuild_id,
597 struct nsinfo *nsi,
598 const char *root_dir)
599 {
600 const char *dirname = "/usr/lib/debug/.build-id/";
601 char *realname = NULL;
602 char dirbuf[PATH_MAX];
603 char *debugfile;
604 struct nscookie nsc;
605 size_t len = 0;
606
607 debugfile = calloc(1, PATH_MAX);
608 if (!debugfile)
609 goto out;
610
611 if (root_dir) {
612 path__join(dirbuf, PATH_MAX, root_dir, dirname);
613 dirname = dirbuf;
614 }
615
616 len = __symbol__join_symfs(debugfile, PATH_MAX, dirname);
617 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
618 sbuild_id + 2);
619
620 nsinfo__mountns_enter(nsi, &nsc);
621 realname = realpath(debugfile, NULL);
622 if (realname && access(realname, R_OK))
623 zfree(&realname);
624 nsinfo__mountns_exit(&nsc);
625
626 #ifdef HAVE_DEBUGINFOD_SUPPORT
627 if (realname == NULL) {
628 debuginfod_client* c;
629
630 pr_debug("Downloading debug info with build id %s\n", sbuild_id);
631
632 c = debuginfod_begin();
633 if (c != NULL) {
634 int fd = debuginfod_find_debuginfo(c,
635 (const unsigned char*)sbuild_id, 0,
636 &realname);
637 if (fd >= 0)
638 close(fd); /* retaining reference by realname */
639 debuginfod_end(c);
640 }
641 }
642 #endif
643
644 out:
645 free(debugfile);
646 return realname;
647 }
648
649 int
650 build_id_cache__add(const char *sbuild_id, const char *name, const char *realname,
651 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
652 const char *proper_name, const char *root_dir)
653 {
654 const size_t size = PATH_MAX;
655 char *filename = NULL, *dir_name = NULL, *linkname = zalloc(size), *tmp;
656 char *debugfile = NULL;
657 int err = -1;
658
659 if (!proper_name)
660 proper_name = name;
661
662 dir_name = build_id_cache__cachedir(sbuild_id, proper_name, nsi, is_kallsyms,
663 is_vdso);
664 if (!dir_name)
665 goto out_free;
666
667 /* Remove old style build-id cache */
668 if (is_regular_file(dir_name))
669 if (unlink(dir_name))
670 goto out_free;
671
672 if (mkdir_p(dir_name, 0755))
673 goto out_free;
674
675 /* Save the allocated buildid dirname */
676 if (asprintf(&filename, "%s/%s", dir_name,
677 build_id_cache__basename(is_kallsyms, is_vdso,
678 false)) < 0) {
679 filename = NULL;
680 goto out_free;
681 }
682
683 if (access(filename, F_OK)) {
684 if (is_kallsyms) {
685 if (copyfile("/proc/kallsyms", filename))
686 goto out_free;
687 } else if (nsi && nsinfo__need_setns(nsi)) {
688 if (copyfile_ns(name, filename, nsi))
689 goto out_free;
690 } else if (link(realname, filename) && errno != EEXIST) {
691 struct stat f_stat;
692
693 if (!(stat(name, &f_stat) < 0) &&
694 copyfile_mode(name, filename, f_stat.st_mode))
695 goto out_free;
696 }
697 }
698
699 /* Some binaries are stripped, but have .debug files with their symbol
700 * table. Check to see if we can locate one of those, since the elf
701 * file itself may not be very useful to users of our tools without a
702 * symtab.
703 */
704 if (!is_kallsyms && !is_vdso &&
705 strncmp(".ko", name + strlen(name) - 3, 3)) {
706 debugfile = build_id_cache__find_debug(sbuild_id, nsi, root_dir);
707 if (debugfile) {
708 zfree(&filename);
709 if (asprintf(&filename, "%s/%s", dir_name,
710 build_id_cache__basename(false, false, true)) < 0) {
711 filename = NULL;
712 goto out_free;
713 }
714 if (access(filename, F_OK)) {
715 if (nsi && nsinfo__need_setns(nsi)) {
716 if (copyfile_ns(debugfile, filename,
717 nsi))
718 goto out_free;
719 } else if (link(debugfile, filename) &&
720 errno != EEXIST &&
721 copyfile(debugfile, filename))
722 goto out_free;
723 }
724 }
725 }
726
727 if (!build_id_cache__linkname(sbuild_id, linkname, size))
728 goto out_free;
729 tmp = strrchr(linkname, '/');
730 *tmp = '\0';
731
732 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
733 goto out_free;
734
735 *tmp = '/';
736 tmp = dir_name + strlen(buildid_dir) - 5;
737 memcpy(tmp, "../..", 5);
738
739 if (symlink(tmp, linkname) == 0) {
740 err = 0;
741 } else if (errno == EEXIST) {
742 char path[PATH_MAX];
743 ssize_t len;
744
745 len = readlink(linkname, path, sizeof(path) - 1);
746 if (len <= 0) {
747 pr_err("Can't read link: %s\n", linkname);
748 goto out_free;
749 }
750 path[len] = '\0';
751
752 if (strcmp(tmp, path)) {
753 pr_debug("build <%s> already linked to %s\n",
754 sbuild_id, linkname);
755 }
756 err = 0;
757 }
758
759 /* Update SDT cache : error is just warned */
760 if (realname &&
761 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
762 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
763
764 out_free:
765 free(filename);
766 free(debugfile);
767 free(dir_name);
768 free(linkname);
769 return err;
770 }
771
772 int __build_id_cache__add_s(const char *sbuild_id, const char *name,
773 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
774 const char *proper_name, const char *root_dir)
775 {
776 char *realname = NULL;
777 int err = -1;
778
779 if (!is_kallsyms) {
780 if (!is_vdso)
781 realname = nsinfo__realpath(name, nsi);
782 else
783 realname = realpath(name, NULL);
784 if (!realname)
785 goto out_free;
786 }
787
788 err = build_id_cache__add(sbuild_id, name, realname, nsi,
789 is_kallsyms, is_vdso, proper_name, root_dir);
790 out_free:
791 if (!is_kallsyms)
792 free(realname);
793 return err;
794 }
795
796 static int build_id_cache__add_b(const struct build_id *bid,
797 const char *name, struct nsinfo *nsi,
798 bool is_kallsyms, bool is_vdso,
799 const char *proper_name,
800 const char *root_dir)
801 {
802 char sbuild_id[SBUILD_ID_SIZE];
803
804 build_id__sprintf(bid, sbuild_id);
805
806 return __build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
807 is_vdso, proper_name, root_dir);
808 }
809
810 bool build_id_cache__cached(const char *sbuild_id)
811 {
812 bool ret = false;
813 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
814
815 if (filename && !access(filename, F_OK))
816 ret = true;
817 free(filename);
818
819 return ret;
820 }
821
822 int build_id_cache__remove_s(const char *sbuild_id)
823 {
824 const size_t size = PATH_MAX;
825 char *filename = zalloc(size),
826 *linkname = zalloc(size), *tmp;
827 int err = -1;
828
829 if (filename == NULL || linkname == NULL)
830 goto out_free;
831
832 if (!build_id_cache__linkname(sbuild_id, linkname, size))
833 goto out_free;
834
835 if (access(linkname, F_OK))
836 goto out_free;
837
838 if (readlink(linkname, filename, size - 1) < 0)
839 goto out_free;
840
841 if (unlink(linkname))
842 goto out_free;
843
844 /*
845 * Since the link is relative, we must make it absolute:
846 */
847 tmp = strrchr(linkname, '/') + 1;
848 snprintf(tmp, size - (tmp - linkname), "%s", filename);
849
850 if (rm_rf(linkname))
851 goto out_free;
852
853 err = 0;
854 out_free:
855 free(filename);
856 free(linkname);
857 return err;
858 }
859
860 static int filename__read_build_id_ns(const char *filename,
861 struct build_id *bid,
862 struct nsinfo *nsi)
863 {
864 struct nscookie nsc;
865 int ret;
866
867 nsinfo__mountns_enter(nsi, &nsc);
868 ret = filename__read_build_id(filename, bid);
869 nsinfo__mountns_exit(&nsc);
870
871 return ret;
872 }
873
874 static bool dso__build_id_mismatch(struct dso *dso, const char *name)
875 {
876 struct build_id bid;
877 bool ret = false;
878
879 mutex_lock(dso__lock(dso));
880 if (filename__read_build_id_ns(name, &bid, dso__nsinfo(dso)) >= 0)
881 ret = !dso__build_id_equal(dso, &bid);
882
883 mutex_unlock(dso__lock(dso));
884
885 return ret;
886 }
887
888 static int dso__cache_build_id(struct dso *dso, struct machine *machine,
889 void *priv __maybe_unused)
890 {
891 bool is_kallsyms = dso__is_kallsyms(dso);
892 bool is_vdso = dso__is_vdso(dso);
893 const char *name = dso__long_name(dso);
894 const char *proper_name = NULL;
895 const char *root_dir = NULL;
896 char *allocated_name = NULL;
897 int ret = 0;
898
899 if (!dso__has_build_id(dso))
900 return 0;
901
902 if (dso__is_kcore(dso)) {
903 is_kallsyms = true;
904 name = machine->mmap_name;
905 }
906
907 if (!machine__is_host(machine)) {
908 if (*machine->root_dir) {
909 root_dir = machine->root_dir;
910 ret = asprintf(&allocated_name, "%s/%s", root_dir, name);
911 if (ret < 0)
912 return ret;
913 proper_name = name;
914 name = allocated_name;
915 } else if (is_kallsyms) {
916 /* Cannot get guest kallsyms */
917 return 0;
918 }
919 }
920
921 if (!is_kallsyms && dso__build_id_mismatch(dso, name))
922 goto out_free;
923
924 mutex_lock(dso__lock(dso));
925 ret = build_id_cache__add_b(dso__bid(dso), name, dso__nsinfo(dso),
926 is_kallsyms, is_vdso, proper_name, root_dir);
927 mutex_unlock(dso__lock(dso));
928 out_free:
929 free(allocated_name);
930 return ret;
931 }
932
933 static int
934 machines__for_each_dso(struct machines *machines, machine__dso_t fn, void *priv)
935 {
936 int ret = machine__for_each_dso(&machines->host, fn, priv);
937 struct rb_node *nd;
938
939 for (nd = rb_first_cached(&machines->guests); nd;
940 nd = rb_next(nd)) {
941 struct machine *pos = rb_entry(nd, struct machine, rb_node);
942
943 ret |= machine__for_each_dso(pos, fn, priv);
944 }
945 return ret ? -1 : 0;
946 }
947
948 int __perf_session__cache_build_ids(struct perf_session *session,
949 machine__dso_t fn, void *priv)
950 {
951 if (no_buildid_cache)
952 return 0;
953
954 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
955 return -1;
956
957 return machines__for_each_dso(&session->machines, fn, priv) ? -1 : 0;
958 }
959
960 int perf_session__cache_build_ids(struct perf_session *session)
961 {
962 return __perf_session__cache_build_ids(session, dso__cache_build_id, NULL);
963 }
964
965 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
966 {
967 return dsos__read_build_ids(&machine->dsos, with_hits);
968 }
969
970 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
971 {
972 struct rb_node *nd;
973 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
974
975 for (nd = rb_first_cached(&session->machines.guests); nd;
976 nd = rb_next(nd)) {
977 struct machine *pos = rb_entry(nd, struct machine, rb_node);
978 ret |= machine__read_build_ids(pos, with_hits);
979 }
980
981 return ret;
982 }
983
984 void build_id__init(struct build_id *bid, const u8 *data, size_t size)
985 {
986 WARN_ON(size > BUILD_ID_SIZE);
987 memcpy(bid->data, data, size);
988 bid->size = size;
989 }
990
991 bool build_id__is_defined(const struct build_id *bid)
992 {
993 return bid && bid->size ? !!memchr_inv(bid->data, 0, bid->size) : false;
994 }
995
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