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