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