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