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 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 68 static 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 89 struct 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 }; 99 100 int 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 } 116 117 int 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 } 134 135 int 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 */ 148 static 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 } 165 166 char *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); 173 retry: 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 } 186 187 char *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. */ 198 char *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 } 227 out: 228 free(linkname); 229 return ret; 230 } 231 232 /* Check if the given build_id cache is valid on current running system */ 233 static 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 } 256 257 static 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 } 263 264 char *__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 } 294 295 char *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 308 309 static 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 } 333 334 static 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 } 377 378 int 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 } 396 397 static 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 } 406 407 static int machine__hit_all_dsos(struct machine *machine) 408 { 409 return __dsos__hit_all(&machine->dsos.head); 410 } 411 412 int 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 } 432 433 void disable_buildid_cache(void) 434 { 435 no_buildid_cache = true; 436 } 437 438 static 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 } 444 445 static 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_SIZE - 3) && (d->d_name[i] == '\0'); 452 } 453 454 struct strlist *build_id_cache__list_all(bool validonly) 455 { 456 struct strlist *toplist, *linklist = NULL, *bidlist; 457 struct str_node *nd, *nd2; 458 char *topdir, *linkdir = NULL; 459 char sbuild_id[SBUILD_ID_SIZE]; 460 461 /* for filename__ functions */ 462 if (validonly) 463 symbol__init(NULL); 464 465 /* Open the top-level directory */ 466 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0) 467 return NULL; 468 469 bidlist = strlist__new(NULL, NULL); 470 if (!bidlist) 471 goto out; 472 473 toplist = lsdir(topdir, lsdir_bid_head_filter); 474 if (!toplist) { 475 pr_debug("Error in lsdir(%s): %d\n", topdir, errno); 476 /* If there is no buildid cache, return an empty list */ 477 if (errno == ENOENT) 478 goto out; 479 goto err_out; 480 } 481 482 strlist__for_each_entry(nd, toplist) { 483 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0) 484 goto err_out; 485 /* Open the lower-level directory */ 486 linklist = lsdir(linkdir, lsdir_bid_tail_filter); 487 if (!linklist) { 488 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno); 489 goto err_out; 490 } 491 strlist__for_each_entry(nd2, linklist) { 492 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s", 493 nd->s, nd2->s) != SBUILD_ID_SIZE - 1) 494 goto err_out; 495 if (validonly && !build_id_cache__valid_id(sbuild_id)) 496 continue; 497 if (strlist__add(bidlist, sbuild_id) < 0) 498 goto err_out; 499 } 500 strlist__delete(linklist); 501 zfree(&linkdir); 502 } 503 504 out_free: 505 strlist__delete(toplist); 506 out: 507 free(topdir); 508 509 return bidlist; 510 511 err_out: 512 strlist__delete(linklist); 513 zfree(&linkdir); 514 strlist__delete(bidlist); 515 bidlist = NULL; 516 goto out_free; 517 } 518 519 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len) 520 { 521 size_t i; 522 523 for (i = 0; i < len; i++) { 524 if (!isxdigit(maybe_sbuild_id[i])) 525 return false; 526 } 527 return true; 528 } 529 530 /* Return the valid complete build-id */ 531 char *build_id_cache__complement(const char *incomplete_sbuild_id) 532 { 533 struct strlist *bidlist; 534 struct str_node *nd, *cand = NULL; 535 char *sbuild_id = NULL; 536 size_t len = strlen(incomplete_sbuild_id); 537 538 if (len >= SBUILD_ID_SIZE || 539 !str_is_build_id(incomplete_sbuild_id, len)) 540 return NULL; 541 542 bidlist = build_id_cache__list_all(true); 543 if (!bidlist) 544 return NULL; 545 546 strlist__for_each_entry(nd, bidlist) { 547 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0) 548 continue; 549 if (cand) { /* Error: There are more than 2 candidates. */ 550 cand = NULL; 551 break; 552 } 553 cand = nd; 554 } 555 if (cand) 556 sbuild_id = strdup(cand->s); 557 strlist__delete(bidlist); 558 559 return sbuild_id; 560 } 561 562 char *build_id_cache__cachedir(const char *sbuild_id, const char *name, 563 struct nsinfo *nsi, bool is_kallsyms, 564 bool is_vdso) 565 { 566 char *realname = (char *)name, *filename; 567 bool slash = is_kallsyms || is_vdso; 568 569 if (!slash) { 570 realname = nsinfo__realpath(name, nsi); 571 if (!realname) 572 return NULL; 573 } 574 575 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "", 576 is_vdso ? DSO__NAME_VDSO : realname, 577 sbuild_id ? "/" : "", sbuild_id ?: "") < 0) 578 filename = NULL; 579 580 if (!slash) 581 free(realname); 582 583 return filename; 584 } 585 586 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi, 587 struct strlist **result) 588 { 589 char *dir_name; 590 int ret = 0; 591 592 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false); 593 if (!dir_name) 594 return -ENOMEM; 595 596 *result = lsdir(dir_name, lsdir_no_dot_filter); 597 if (!*result) 598 ret = -errno; 599 free(dir_name); 600 601 return ret; 602 } 603 604 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT) 605 static int build_id_cache__add_sdt_cache(const char *sbuild_id, 606 const char *realname, 607 struct nsinfo *nsi) 608 { 609 struct probe_cache *cache; 610 int ret; 611 struct nscookie nsc; 612 613 cache = probe_cache__new(sbuild_id, nsi); 614 if (!cache) 615 return -1; 616 617 nsinfo__mountns_enter(nsi, &nsc); 618 ret = probe_cache__scan_sdt(cache, realname); 619 nsinfo__mountns_exit(&nsc); 620 if (ret >= 0) { 621 pr_debug4("Found %d SDTs in %s\n", ret, realname); 622 if (probe_cache__commit(cache) < 0) 623 ret = -1; 624 } 625 probe_cache__delete(cache); 626 return ret; 627 } 628 #else 629 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0) 630 #endif 631 632 static char *build_id_cache__find_debug(const char *sbuild_id, 633 struct nsinfo *nsi) 634 { 635 char *realname = NULL; 636 char *debugfile; 637 struct nscookie nsc; 638 size_t len = 0; 639 640 debugfile = calloc(1, PATH_MAX); 641 if (!debugfile) 642 goto out; 643 644 len = __symbol__join_symfs(debugfile, PATH_MAX, 645 "/usr/lib/debug/.build-id/"); 646 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id, 647 sbuild_id + 2); 648 649 nsinfo__mountns_enter(nsi, &nsc); 650 realname = realpath(debugfile, NULL); 651 if (realname && access(realname, R_OK)) 652 zfree(&realname); 653 nsinfo__mountns_exit(&nsc); 654 655 #ifdef HAVE_DEBUGINFOD_SUPPORT 656 if (realname == NULL) { 657 debuginfod_client* c = debuginfod_begin(); 658 if (c != NULL) { 659 int fd = debuginfod_find_debuginfo(c, 660 (const unsigned char*)sbuild_id, 0, 661 &realname); 662 if (fd >= 0) 663 close(fd); /* retaining reference by realname */ 664 debuginfod_end(c); 665 } 666 } 667 #endif 668 669 out: 670 free(debugfile); 671 return realname; 672 } 673 674 int 675 build_id_cache__add(const char *sbuild_id, const char *name, const char *realname, 676 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso) 677 { 678 const size_t size = PATH_MAX; 679 char *filename = NULL, *dir_name = NULL, *linkname = zalloc(size), *tmp; 680 char *debugfile = NULL; 681 int err = -1; 682 683 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms, 684 is_vdso); 685 if (!dir_name) 686 goto out_free; 687 688 /* Remove old style build-id cache */ 689 if (is_regular_file(dir_name)) 690 if (unlink(dir_name)) 691 goto out_free; 692 693 if (mkdir_p(dir_name, 0755)) 694 goto out_free; 695 696 /* Save the allocated buildid dirname */ 697 if (asprintf(&filename, "%s/%s", dir_name, 698 build_id_cache__basename(is_kallsyms, is_vdso, 699 false)) < 0) { 700 filename = NULL; 701 goto out_free; 702 } 703 704 if (access(filename, F_OK)) { 705 if (is_kallsyms) { 706 if (copyfile("/proc/kallsyms", filename)) 707 goto out_free; 708 } else if (nsi && nsi->need_setns) { 709 if (copyfile_ns(name, filename, nsi)) 710 goto out_free; 711 } else if (link(realname, filename) && errno != EEXIST && 712 copyfile(name, filename)) 713 goto out_free; 714 } 715 716 /* Some binaries are stripped, but have .debug files with their symbol 717 * table. Check to see if we can locate one of those, since the elf 718 * file itself may not be very useful to users of our tools without a 719 * symtab. 720 */ 721 if (!is_kallsyms && !is_vdso && 722 strncmp(".ko", name + strlen(name) - 3, 3)) { 723 debugfile = build_id_cache__find_debug(sbuild_id, nsi); 724 if (debugfile) { 725 zfree(&filename); 726 if (asprintf(&filename, "%s/%s", dir_name, 727 build_id_cache__basename(false, false, true)) < 0) { 728 filename = NULL; 729 goto out_free; 730 } 731 if (access(filename, F_OK)) { 732 if (nsi && nsi->need_setns) { 733 if (copyfile_ns(debugfile, filename, 734 nsi)) 735 goto out_free; 736 } else if (link(debugfile, filename) && 737 errno != EEXIST && 738 copyfile(debugfile, filename)) 739 goto out_free; 740 } 741 } 742 } 743 744 if (!build_id_cache__linkname(sbuild_id, linkname, size)) 745 goto out_free; 746 tmp = strrchr(linkname, '/'); 747 *tmp = '\0'; 748 749 if (access(linkname, X_OK) && mkdir_p(linkname, 0755)) 750 goto out_free; 751 752 *tmp = '/'; 753 tmp = dir_name + strlen(buildid_dir) - 5; 754 memcpy(tmp, "../..", 5); 755 756 if (symlink(tmp, linkname) == 0) { 757 err = 0; 758 } else if (errno == EEXIST) { 759 char path[PATH_MAX]; 760 ssize_t len; 761 762 len = readlink(linkname, path, sizeof(path) - 1); 763 if (len <= 0) { 764 pr_err("Cant read link: %s\n", linkname); 765 goto out_free; 766 } 767 path[len] = '\0'; 768 769 if (strcmp(tmp, path)) { 770 pr_debug("build <%s> already linked to %s\n", 771 sbuild_id, linkname); 772 } 773 err = 0; 774 } 775 776 /* Update SDT cache : error is just warned */ 777 if (realname && 778 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0) 779 pr_debug4("Failed to update/scan SDT cache for %s\n", realname); 780 781 out_free: 782 free(filename); 783 free(debugfile); 784 free(dir_name); 785 free(linkname); 786 return err; 787 } 788 789 int build_id_cache__add_s(const char *sbuild_id, const char *name, 790 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso) 791 { 792 char *realname = NULL; 793 int err = -1; 794 795 if (!is_kallsyms) { 796 if (!is_vdso) 797 realname = nsinfo__realpath(name, nsi); 798 else 799 realname = realpath(name, NULL); 800 if (!realname) 801 goto out_free; 802 } 803 804 err = build_id_cache__add(sbuild_id, name, realname, nsi, is_kallsyms, is_vdso); 805 806 out_free: 807 if (!is_kallsyms) 808 free(realname); 809 return err; 810 } 811 812 static int build_id_cache__add_b(const struct build_id *bid, 813 const char *name, struct nsinfo *nsi, 814 bool is_kallsyms, bool is_vdso) 815 { 816 char sbuild_id[SBUILD_ID_SIZE]; 817 818 build_id__sprintf(bid, sbuild_id); 819 820 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms, 821 is_vdso); 822 } 823 824 bool build_id_cache__cached(const char *sbuild_id) 825 { 826 bool ret = false; 827 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0); 828 829 if (filename && !access(filename, F_OK)) 830 ret = true; 831 free(filename); 832 833 return ret; 834 } 835 836 int build_id_cache__remove_s(const char *sbuild_id) 837 { 838 const size_t size = PATH_MAX; 839 char *filename = zalloc(size), 840 *linkname = zalloc(size), *tmp; 841 int err = -1; 842 843 if (filename == NULL || linkname == NULL) 844 goto out_free; 845 846 if (!build_id_cache__linkname(sbuild_id, linkname, size)) 847 goto out_free; 848 849 if (access(linkname, F_OK)) 850 goto out_free; 851 852 if (readlink(linkname, filename, size - 1) < 0) 853 goto out_free; 854 855 if (unlink(linkname)) 856 goto out_free; 857 858 /* 859 * Since the link is relative, we must make it absolute: 860 */ 861 tmp = strrchr(linkname, '/') + 1; 862 snprintf(tmp, size - (tmp - linkname), "%s", filename); 863 864 if (rm_rf(linkname)) 865 goto out_free; 866 867 err = 0; 868 out_free: 869 free(filename); 870 free(linkname); 871 return err; 872 } 873 874 static int dso__cache_build_id(struct dso *dso, struct machine *machine, 875 void *priv __maybe_unused) 876 { 877 bool is_kallsyms = dso__is_kallsyms(dso); 878 bool is_vdso = dso__is_vdso(dso); 879 const char *name = dso->long_name; 880 881 if (!dso->has_build_id) 882 return 0; 883 884 if (dso__is_kcore(dso)) { 885 is_kallsyms = true; 886 name = machine->mmap_name; 887 } 888 return build_id_cache__add_b(&dso->bid, name, dso->nsinfo, 889 is_kallsyms, is_vdso); 890 } 891 892 static int 893 machines__for_each_dso(struct machines *machines, machine__dso_t fn, void *priv) 894 { 895 int ret = machine__for_each_dso(&machines->host, fn, priv); 896 struct rb_node *nd; 897 898 for (nd = rb_first_cached(&machines->guests); nd; 899 nd = rb_next(nd)) { 900 struct machine *pos = rb_entry(nd, struct machine, rb_node); 901 902 ret |= machine__for_each_dso(pos, fn, priv); 903 } 904 return ret ? -1 : 0; 905 } 906 907 int __perf_session__cache_build_ids(struct perf_session *session, 908 machine__dso_t fn, void *priv) 909 { 910 if (no_buildid_cache) 911 return 0; 912 913 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST) 914 return -1; 915 916 return machines__for_each_dso(&session->machines, fn, priv) ? -1 : 0; 917 } 918 919 int perf_session__cache_build_ids(struct perf_session *session) 920 { 921 return __perf_session__cache_build_ids(session, dso__cache_build_id, NULL); 922 } 923 924 static bool machine__read_build_ids(struct machine *machine, bool with_hits) 925 { 926 return __dsos__read_build_ids(&machine->dsos.head, with_hits); 927 } 928 929 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits) 930 { 931 struct rb_node *nd; 932 bool ret = machine__read_build_ids(&session->machines.host, with_hits); 933 934 for (nd = rb_first_cached(&session->machines.guests); nd; 935 nd = rb_next(nd)) { 936 struct machine *pos = rb_entry(nd, struct machine, rb_node); 937 ret |= machine__read_build_ids(pos, with_hits); 938 } 939 940 return ret; 941 } 942 943 void build_id__init(struct build_id *bid, const u8 *data, size_t size) 944 { 945 WARN_ON(size > BUILD_ID_SIZE); 946 memcpy(bid->data, data, size); 947 bid->size = size; 948 } 949 950 bool build_id__is_defined(const struct build_id *bid) 951 { 952 return bid && bid->size ? !!memchr_inv(bid->data, 0, bid->size) : false; 953 } 954