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