1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * probe-event.c : perf-probe definition to probe_events format converter 4 * 5 * Written by Masami Hiramatsu <mhiramat@redhat.com> 6 */ 7 8 #include <inttypes.h> 9 #include <sys/utsname.h> 10 #include <sys/types.h> 11 #include <sys/stat.h> 12 #include <fcntl.h> 13 #include <errno.h> 14 #include <stdio.h> 15 #include <unistd.h> 16 #include <stdlib.h> 17 #include <string.h> 18 #include <stdarg.h> 19 #include <limits.h> 20 #include <elf.h> 21 22 #include "build-id.h" 23 #include "event.h" 24 #include "namespaces.h" 25 #include "strlist.h" 26 #include "strfilter.h" 27 #include "debug.h" 28 #include "dso.h" 29 #include "color.h" 30 #include "map.h" 31 #include "maps.h" 32 #include "symbol.h" 33 #include <api/fs/fs.h> 34 #include "trace-event.h" /* For __maybe_unused */ 35 #include "probe-event.h" 36 #include "probe-finder.h" 37 #include "probe-file.h" 38 #include "session.h" 39 #include "string2.h" 40 #include "strbuf.h" 41 42 #include <subcmd/pager.h> 43 #include <linux/ctype.h> 44 #include <linux/zalloc.h> 45 46 #define PERFPROBE_GROUP "probe" 47 48 bool probe_event_dry_run; /* Dry run flag */ 49 struct probe_conf probe_conf = { .magic_num = DEFAULT_PROBE_MAGIC_NUM }; 50 51 #define semantic_error(msg ...) pr_err("Semantic error :" msg) 52 53 int e_snprintf(char *str, size_t size, const char *format, ...) 54 { 55 int ret; 56 va_list ap; 57 va_start(ap, format); 58 ret = vsnprintf(str, size, format, ap); 59 va_end(ap); 60 if (ret >= (int)size) 61 ret = -E2BIG; 62 return ret; 63 } 64 65 static struct machine *host_machine; 66 67 /* Initialize symbol maps and path of vmlinux/modules */ 68 int init_probe_symbol_maps(bool user_only) 69 { 70 int ret; 71 72 symbol_conf.sort_by_name = true; 73 symbol_conf.allow_aliases = true; 74 ret = symbol__init(NULL); 75 if (ret < 0) { 76 pr_debug("Failed to init symbol map.\n"); 77 goto out; 78 } 79 80 if (host_machine || user_only) /* already initialized */ 81 return 0; 82 83 if (symbol_conf.vmlinux_name) 84 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name); 85 86 host_machine = machine__new_host(); 87 if (!host_machine) { 88 pr_debug("machine__new_host() failed.\n"); 89 symbol__exit(); 90 ret = -1; 91 } 92 out: 93 if (ret < 0) 94 pr_warning("Failed to init vmlinux path.\n"); 95 return ret; 96 } 97 98 void exit_probe_symbol_maps(void) 99 { 100 machine__delete(host_machine); 101 host_machine = NULL; 102 symbol__exit(); 103 } 104 105 static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap) 106 { 107 /* kmap->ref_reloc_sym should be set if host_machine is initialized */ 108 struct kmap *kmap; 109 struct map *map = machine__kernel_map(host_machine); 110 111 if (map__load(map) < 0) 112 return NULL; 113 114 kmap = map__kmap(map); 115 if (!kmap) 116 return NULL; 117 118 if (pmap) 119 *pmap = map; 120 121 return kmap->ref_reloc_sym; 122 } 123 124 static int kernel_get_symbol_address_by_name(const char *name, u64 *addr, 125 bool reloc, bool reladdr) 126 { 127 struct ref_reloc_sym *reloc_sym; 128 struct symbol *sym; 129 struct map *map; 130 131 /* ref_reloc_sym is just a label. Need a special fix*/ 132 reloc_sym = kernel_get_ref_reloc_sym(NULL); 133 if (reloc_sym && strcmp(name, reloc_sym->name) == 0) 134 *addr = (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr; 135 else { 136 sym = machine__find_kernel_symbol_by_name(host_machine, name, &map); 137 if (!sym) 138 return -ENOENT; 139 *addr = map->unmap_ip(map, sym->start) - 140 ((reloc) ? 0 : map->reloc) - 141 ((reladdr) ? map->start : 0); 142 } 143 return 0; 144 } 145 146 static struct map *kernel_get_module_map(const char *module) 147 { 148 struct maps *maps = machine__kernel_maps(host_machine); 149 struct map *pos; 150 151 /* A file path -- this is an offline module */ 152 if (module && strchr(module, '/')) 153 return dso__new_map(module); 154 155 if (!module) { 156 pos = machine__kernel_map(host_machine); 157 return map__get(pos); 158 } 159 160 maps__for_each_entry(maps, pos) { 161 /* short_name is "[module]" */ 162 if (strncmp(pos->dso->short_name + 1, module, 163 pos->dso->short_name_len - 2) == 0 && 164 module[pos->dso->short_name_len - 2] == '\0') { 165 return map__get(pos); 166 } 167 } 168 return NULL; 169 } 170 171 struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) 172 { 173 /* Init maps of given executable or kernel */ 174 if (user) { 175 struct map *map; 176 177 map = dso__new_map(target); 178 if (map && map->dso) 179 map->dso->nsinfo = nsinfo__get(nsi); 180 return map; 181 } else { 182 return kernel_get_module_map(target); 183 } 184 } 185 186 static int convert_exec_to_group(const char *exec, char **result) 187 { 188 char *ptr1, *ptr2, *exec_copy; 189 char buf[64]; 190 int ret; 191 192 exec_copy = strdup(exec); 193 if (!exec_copy) 194 return -ENOMEM; 195 196 ptr1 = basename(exec_copy); 197 if (!ptr1) { 198 ret = -EINVAL; 199 goto out; 200 } 201 202 for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) { 203 if (!isalnum(*ptr2) && *ptr2 != '_') { 204 *ptr2 = '\0'; 205 break; 206 } 207 } 208 209 ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1); 210 if (ret < 0) 211 goto out; 212 213 *result = strdup(buf); 214 ret = *result ? 0 : -ENOMEM; 215 216 out: 217 free(exec_copy); 218 return ret; 219 } 220 221 static void clear_perf_probe_point(struct perf_probe_point *pp) 222 { 223 zfree(&pp->file); 224 zfree(&pp->function); 225 zfree(&pp->lazy_line); 226 } 227 228 static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs) 229 { 230 int i; 231 232 for (i = 0; i < ntevs; i++) 233 clear_probe_trace_event(tevs + i); 234 } 235 236 static bool kprobe_blacklist__listed(unsigned long address); 237 static bool kprobe_warn_out_range(const char *symbol, unsigned long address) 238 { 239 struct map *map; 240 bool ret = false; 241 242 map = kernel_get_module_map(NULL); 243 if (map) { 244 ret = address <= map->start || map->end < address; 245 if (ret) 246 pr_warning("%s is out of .text, skip it.\n", symbol); 247 map__put(map); 248 } 249 if (!ret && kprobe_blacklist__listed(address)) { 250 pr_warning("%s is blacklisted function, skip it.\n", symbol); 251 ret = true; 252 } 253 254 return ret; 255 } 256 257 /* 258 * @module can be module name of module file path. In case of path, 259 * inspect elf and find out what is actual module name. 260 * Caller has to free mod_name after using it. 261 */ 262 static char *find_module_name(const char *module) 263 { 264 int fd; 265 Elf *elf; 266 GElf_Ehdr ehdr; 267 GElf_Shdr shdr; 268 Elf_Data *data; 269 Elf_Scn *sec; 270 char *mod_name = NULL; 271 int name_offset; 272 273 fd = open(module, O_RDONLY); 274 if (fd < 0) 275 return NULL; 276 277 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); 278 if (elf == NULL) 279 goto elf_err; 280 281 if (gelf_getehdr(elf, &ehdr) == NULL) 282 goto ret_err; 283 284 sec = elf_section_by_name(elf, &ehdr, &shdr, 285 ".gnu.linkonce.this_module", NULL); 286 if (!sec) 287 goto ret_err; 288 289 data = elf_getdata(sec, NULL); 290 if (!data || !data->d_buf) 291 goto ret_err; 292 293 /* 294 * NOTE: 295 * '.gnu.linkonce.this_module' section of kernel module elf directly 296 * maps to 'struct module' from linux/module.h. This section contains 297 * actual module name which will be used by kernel after loading it. 298 * But, we cannot use 'struct module' here since linux/module.h is not 299 * exposed to user-space. Offset of 'name' has remained same from long 300 * time, so hardcoding it here. 301 */ 302 if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) 303 name_offset = 12; 304 else /* expect ELFCLASS64 by default */ 305 name_offset = 24; 306 307 mod_name = strdup((char *)data->d_buf + name_offset); 308 309 ret_err: 310 elf_end(elf); 311 elf_err: 312 close(fd); 313 return mod_name; 314 } 315 316 #ifdef HAVE_DWARF_SUPPORT 317 318 static int kernel_get_module_dso(const char *module, struct dso **pdso) 319 { 320 struct dso *dso; 321 struct map *map; 322 const char *vmlinux_name; 323 int ret = 0; 324 325 if (module) { 326 char module_name[128]; 327 328 snprintf(module_name, sizeof(module_name), "[%s]", module); 329 map = maps__find_by_name(&host_machine->kmaps, module_name); 330 if (map) { 331 dso = map->dso; 332 goto found; 333 } 334 pr_debug("Failed to find module %s.\n", module); 335 return -ENOENT; 336 } 337 338 map = machine__kernel_map(host_machine); 339 dso = map->dso; 340 341 vmlinux_name = symbol_conf.vmlinux_name; 342 dso->load_errno = 0; 343 if (vmlinux_name) 344 ret = dso__load_vmlinux(dso, map, vmlinux_name, false); 345 else 346 ret = dso__load_vmlinux_path(dso, map); 347 found: 348 *pdso = dso; 349 return ret; 350 } 351 352 /* 353 * Some binaries like glibc have special symbols which are on the symbol 354 * table, but not in the debuginfo. If we can find the address of the 355 * symbol from map, we can translate the address back to the probe point. 356 */ 357 static int find_alternative_probe_point(struct debuginfo *dinfo, 358 struct perf_probe_point *pp, 359 struct perf_probe_point *result, 360 const char *target, struct nsinfo *nsi, 361 bool uprobes) 362 { 363 struct map *map = NULL; 364 struct symbol *sym; 365 u64 address = 0; 366 int ret = -ENOENT; 367 368 /* This can work only for function-name based one */ 369 if (!pp->function || pp->file) 370 return -ENOTSUP; 371 372 map = get_target_map(target, nsi, uprobes); 373 if (!map) 374 return -EINVAL; 375 376 /* Find the address of given function */ 377 map__for_each_symbol_by_name(map, pp->function, sym) { 378 if (uprobes) { 379 address = sym->start; 380 if (sym->type == STT_GNU_IFUNC) 381 pr_warning("Warning: The probe function (%s) is a GNU indirect function.\n" 382 "Consider identifying the final function used at run time and set the probe directly on that.\n", 383 pp->function); 384 } else 385 address = map->unmap_ip(map, sym->start) - map->reloc; 386 break; 387 } 388 if (!address) { 389 ret = -ENOENT; 390 goto out; 391 } 392 pr_debug("Symbol %s address found : %" PRIx64 "\n", 393 pp->function, address); 394 395 ret = debuginfo__find_probe_point(dinfo, (unsigned long)address, 396 result); 397 if (ret <= 0) 398 ret = (!ret) ? -ENOENT : ret; 399 else { 400 result->offset += pp->offset; 401 result->line += pp->line; 402 result->retprobe = pp->retprobe; 403 ret = 0; 404 } 405 406 out: 407 map__put(map); 408 return ret; 409 410 } 411 412 static int get_alternative_probe_event(struct debuginfo *dinfo, 413 struct perf_probe_event *pev, 414 struct perf_probe_point *tmp) 415 { 416 int ret; 417 418 memcpy(tmp, &pev->point, sizeof(*tmp)); 419 memset(&pev->point, 0, sizeof(pev->point)); 420 ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target, 421 pev->nsi, pev->uprobes); 422 if (ret < 0) 423 memcpy(&pev->point, tmp, sizeof(*tmp)); 424 425 return ret; 426 } 427 428 static int get_alternative_line_range(struct debuginfo *dinfo, 429 struct line_range *lr, 430 const char *target, bool user) 431 { 432 struct perf_probe_point pp = { .function = lr->function, 433 .file = lr->file, 434 .line = lr->start }; 435 struct perf_probe_point result; 436 int ret, len = 0; 437 438 memset(&result, 0, sizeof(result)); 439 440 if (lr->end != INT_MAX) 441 len = lr->end - lr->start; 442 ret = find_alternative_probe_point(dinfo, &pp, &result, 443 target, NULL, user); 444 if (!ret) { 445 lr->function = result.function; 446 lr->file = result.file; 447 lr->start = result.line; 448 if (lr->end != INT_MAX) 449 lr->end = lr->start + len; 450 clear_perf_probe_point(&pp); 451 } 452 return ret; 453 } 454 455 /* Open new debuginfo of given module */ 456 static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi, 457 bool silent) 458 { 459 const char *path = module; 460 char reason[STRERR_BUFSIZE]; 461 struct debuginfo *ret = NULL; 462 struct dso *dso = NULL; 463 struct nscookie nsc; 464 int err; 465 466 if (!module || !strchr(module, '/')) { 467 err = kernel_get_module_dso(module, &dso); 468 if (err < 0) { 469 if (!dso || dso->load_errno == 0) { 470 if (!str_error_r(-err, reason, STRERR_BUFSIZE)) 471 strcpy(reason, "(unknown)"); 472 } else 473 dso__strerror_load(dso, reason, STRERR_BUFSIZE); 474 if (!silent) { 475 if (module) 476 pr_err("Module %s is not loaded, please specify its full path name.\n", module); 477 else 478 pr_err("Failed to find the path for the kernel: %s\n", reason); 479 } 480 return NULL; 481 } 482 path = dso->long_name; 483 } 484 nsinfo__mountns_enter(nsi, &nsc); 485 ret = debuginfo__new(path); 486 if (!ret && !silent) { 487 pr_warning("The %s file has no debug information.\n", path); 488 if (!module || !strtailcmp(path, ".ko")) 489 pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, "); 490 else 491 pr_warning("Rebuild with -g, "); 492 pr_warning("or install an appropriate debuginfo package.\n"); 493 } 494 nsinfo__mountns_exit(&nsc); 495 return ret; 496 } 497 498 /* For caching the last debuginfo */ 499 static struct debuginfo *debuginfo_cache; 500 static char *debuginfo_cache_path; 501 502 static struct debuginfo *debuginfo_cache__open(const char *module, bool silent) 503 { 504 const char *path = module; 505 506 /* If the module is NULL, it should be the kernel. */ 507 if (!module) 508 path = "kernel"; 509 510 if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path)) 511 goto out; 512 513 /* Copy module path */ 514 free(debuginfo_cache_path); 515 debuginfo_cache_path = strdup(path); 516 if (!debuginfo_cache_path) { 517 debuginfo__delete(debuginfo_cache); 518 debuginfo_cache = NULL; 519 goto out; 520 } 521 522 debuginfo_cache = open_debuginfo(module, NULL, silent); 523 if (!debuginfo_cache) 524 zfree(&debuginfo_cache_path); 525 out: 526 return debuginfo_cache; 527 } 528 529 static void debuginfo_cache__exit(void) 530 { 531 debuginfo__delete(debuginfo_cache); 532 debuginfo_cache = NULL; 533 zfree(&debuginfo_cache_path); 534 } 535 536 537 static int get_text_start_address(const char *exec, unsigned long *address, 538 struct nsinfo *nsi) 539 { 540 Elf *elf; 541 GElf_Ehdr ehdr; 542 GElf_Shdr shdr; 543 int fd, ret = -ENOENT; 544 struct nscookie nsc; 545 546 nsinfo__mountns_enter(nsi, &nsc); 547 fd = open(exec, O_RDONLY); 548 nsinfo__mountns_exit(&nsc); 549 if (fd < 0) 550 return -errno; 551 552 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); 553 if (elf == NULL) { 554 ret = -EINVAL; 555 goto out_close; 556 } 557 558 if (gelf_getehdr(elf, &ehdr) == NULL) 559 goto out; 560 561 if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL)) 562 goto out; 563 564 *address = shdr.sh_addr - shdr.sh_offset; 565 ret = 0; 566 out: 567 elf_end(elf); 568 out_close: 569 close(fd); 570 571 return ret; 572 } 573 574 /* 575 * Convert trace point to probe point with debuginfo 576 */ 577 static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp, 578 struct perf_probe_point *pp, 579 bool is_kprobe) 580 { 581 struct debuginfo *dinfo = NULL; 582 unsigned long stext = 0; 583 u64 addr = tp->address; 584 int ret = -ENOENT; 585 586 /* convert the address to dwarf address */ 587 if (!is_kprobe) { 588 if (!addr) { 589 ret = -EINVAL; 590 goto error; 591 } 592 ret = get_text_start_address(tp->module, &stext, NULL); 593 if (ret < 0) 594 goto error; 595 addr += stext; 596 } else if (tp->symbol) { 597 /* If the module is given, this returns relative address */ 598 ret = kernel_get_symbol_address_by_name(tp->symbol, &addr, 599 false, !!tp->module); 600 if (ret != 0) 601 goto error; 602 addr += tp->offset; 603 } 604 605 pr_debug("try to find information at %" PRIx64 " in %s\n", addr, 606 tp->module ? : "kernel"); 607 608 dinfo = debuginfo_cache__open(tp->module, verbose <= 0); 609 if (dinfo) 610 ret = debuginfo__find_probe_point(dinfo, 611 (unsigned long)addr, pp); 612 else 613 ret = -ENOENT; 614 615 if (ret > 0) { 616 pp->retprobe = tp->retprobe; 617 return 0; 618 } 619 error: 620 pr_debug("Failed to find corresponding probes from debuginfo.\n"); 621 return ret ? : -ENOENT; 622 } 623 624 /* Adjust symbol name and address */ 625 static int post_process_probe_trace_point(struct probe_trace_point *tp, 626 struct map *map, unsigned long offs) 627 { 628 struct symbol *sym; 629 u64 addr = tp->address - offs; 630 631 sym = map__find_symbol(map, addr); 632 if (!sym) 633 return -ENOENT; 634 635 if (strcmp(sym->name, tp->symbol)) { 636 /* If we have no realname, use symbol for it */ 637 if (!tp->realname) 638 tp->realname = tp->symbol; 639 else 640 free(tp->symbol); 641 tp->symbol = strdup(sym->name); 642 if (!tp->symbol) 643 return -ENOMEM; 644 } 645 tp->offset = addr - sym->start; 646 tp->address -= offs; 647 648 return 0; 649 } 650 651 /* 652 * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions 653 * and generate new symbols with suffixes such as .constprop.N or .isra.N 654 * etc. Since those symbols are not recorded in DWARF, we have to find 655 * correct generated symbols from offline ELF binary. 656 * For online kernel or uprobes we don't need this because those are 657 * rebased on _text, or already a section relative address. 658 */ 659 static int 660 post_process_offline_probe_trace_events(struct probe_trace_event *tevs, 661 int ntevs, const char *pathname) 662 { 663 struct map *map; 664 unsigned long stext = 0; 665 int i, ret = 0; 666 667 /* Prepare a map for offline binary */ 668 map = dso__new_map(pathname); 669 if (!map || get_text_start_address(pathname, &stext, NULL) < 0) { 670 pr_warning("Failed to get ELF symbols for %s\n", pathname); 671 return -EINVAL; 672 } 673 674 for (i = 0; i < ntevs; i++) { 675 ret = post_process_probe_trace_point(&tevs[i].point, 676 map, stext); 677 if (ret < 0) 678 break; 679 } 680 map__put(map); 681 682 return ret; 683 } 684 685 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, 686 int ntevs, const char *exec, 687 struct nsinfo *nsi) 688 { 689 int i, ret = 0; 690 unsigned long stext = 0; 691 692 if (!exec) 693 return 0; 694 695 ret = get_text_start_address(exec, &stext, nsi); 696 if (ret < 0) 697 return ret; 698 699 for (i = 0; i < ntevs && ret >= 0; i++) { 700 /* point.address is the address of point.symbol + point.offset */ 701 tevs[i].point.address -= stext; 702 tevs[i].point.module = strdup(exec); 703 if (!tevs[i].point.module) { 704 ret = -ENOMEM; 705 break; 706 } 707 tevs[i].uprobes = true; 708 } 709 710 return ret; 711 } 712 713 static int 714 post_process_module_probe_trace_events(struct probe_trace_event *tevs, 715 int ntevs, const char *module, 716 struct debuginfo *dinfo) 717 { 718 Dwarf_Addr text_offs = 0; 719 int i, ret = 0; 720 char *mod_name = NULL; 721 struct map *map; 722 723 if (!module) 724 return 0; 725 726 map = get_target_map(module, NULL, false); 727 if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) { 728 pr_warning("Failed to get ELF symbols for %s\n", module); 729 return -EINVAL; 730 } 731 732 mod_name = find_module_name(module); 733 for (i = 0; i < ntevs; i++) { 734 ret = post_process_probe_trace_point(&tevs[i].point, 735 map, (unsigned long)text_offs); 736 if (ret < 0) 737 break; 738 tevs[i].point.module = 739 strdup(mod_name ? mod_name : module); 740 if (!tevs[i].point.module) { 741 ret = -ENOMEM; 742 break; 743 } 744 } 745 746 free(mod_name); 747 map__put(map); 748 749 return ret; 750 } 751 752 static int 753 post_process_kernel_probe_trace_events(struct probe_trace_event *tevs, 754 int ntevs) 755 { 756 struct ref_reloc_sym *reloc_sym; 757 struct map *map; 758 char *tmp; 759 int i, skipped = 0; 760 761 /* Skip post process if the target is an offline kernel */ 762 if (symbol_conf.ignore_vmlinux_buildid) 763 return post_process_offline_probe_trace_events(tevs, ntevs, 764 symbol_conf.vmlinux_name); 765 766 reloc_sym = kernel_get_ref_reloc_sym(&map); 767 if (!reloc_sym) { 768 pr_warning("Relocated base symbol is not found!\n"); 769 return -EINVAL; 770 } 771 772 for (i = 0; i < ntevs; i++) { 773 if (!tevs[i].point.address) 774 continue; 775 if (tevs[i].point.retprobe && !kretprobe_offset_is_supported()) 776 continue; 777 /* 778 * If we found a wrong one, mark it by NULL symbol. 779 * Since addresses in debuginfo is same as objdump, we need 780 * to convert it to addresses on memory. 781 */ 782 if (kprobe_warn_out_range(tevs[i].point.symbol, 783 map__objdump_2mem(map, tevs[i].point.address))) { 784 tmp = NULL; 785 skipped++; 786 } else { 787 tmp = strdup(reloc_sym->name); 788 if (!tmp) 789 return -ENOMEM; 790 } 791 /* If we have no realname, use symbol for it */ 792 if (!tevs[i].point.realname) 793 tevs[i].point.realname = tevs[i].point.symbol; 794 else 795 free(tevs[i].point.symbol); 796 tevs[i].point.symbol = tmp; 797 tevs[i].point.offset = tevs[i].point.address - 798 reloc_sym->unrelocated_addr; 799 } 800 return skipped; 801 } 802 803 void __weak 804 arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused, 805 int ntevs __maybe_unused) 806 { 807 } 808 809 /* Post processing the probe events */ 810 static int post_process_probe_trace_events(struct perf_probe_event *pev, 811 struct probe_trace_event *tevs, 812 int ntevs, const char *module, 813 bool uprobe, struct debuginfo *dinfo) 814 { 815 int ret; 816 817 if (uprobe) 818 ret = add_exec_to_probe_trace_events(tevs, ntevs, module, 819 pev->nsi); 820 else if (module) 821 /* Currently ref_reloc_sym based probe is not for drivers */ 822 ret = post_process_module_probe_trace_events(tevs, ntevs, 823 module, dinfo); 824 else 825 ret = post_process_kernel_probe_trace_events(tevs, ntevs); 826 827 if (ret >= 0) 828 arch__post_process_probe_trace_events(pev, ntevs); 829 830 return ret; 831 } 832 833 /* Try to find perf_probe_event with debuginfo */ 834 static int try_to_find_probe_trace_events(struct perf_probe_event *pev, 835 struct probe_trace_event **tevs) 836 { 837 bool need_dwarf = perf_probe_event_need_dwarf(pev); 838 struct perf_probe_point tmp; 839 struct debuginfo *dinfo; 840 int ntevs, ret = 0; 841 842 dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf); 843 if (!dinfo) { 844 if (need_dwarf) 845 return -ENOENT; 846 pr_debug("Could not open debuginfo. Try to use symbols.\n"); 847 return 0; 848 } 849 850 pr_debug("Try to find probe point from debuginfo.\n"); 851 /* Searching trace events corresponding to a probe event */ 852 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); 853 854 if (ntevs == 0) { /* Not found, retry with an alternative */ 855 ret = get_alternative_probe_event(dinfo, pev, &tmp); 856 if (!ret) { 857 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); 858 /* 859 * Write back to the original probe_event for 860 * setting appropriate (user given) event name 861 */ 862 clear_perf_probe_point(&pev->point); 863 memcpy(&pev->point, &tmp, sizeof(tmp)); 864 } 865 } 866 867 if (ntevs > 0) { /* Succeeded to find trace events */ 868 pr_debug("Found %d probe_trace_events.\n", ntevs); 869 ret = post_process_probe_trace_events(pev, *tevs, ntevs, 870 pev->target, pev->uprobes, dinfo); 871 if (ret < 0 || ret == ntevs) { 872 pr_debug("Post processing failed or all events are skipped. (%d)\n", ret); 873 clear_probe_trace_events(*tevs, ntevs); 874 zfree(tevs); 875 ntevs = 0; 876 } 877 } 878 879 debuginfo__delete(dinfo); 880 881 if (ntevs == 0) { /* No error but failed to find probe point. */ 882 pr_warning("Probe point '%s' not found.\n", 883 synthesize_perf_probe_point(&pev->point)); 884 return -ENOENT; 885 } else if (ntevs < 0) { 886 /* Error path : ntevs < 0 */ 887 pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs); 888 if (ntevs == -EBADF) 889 pr_warning("Warning: No dwarf info found in the vmlinux - " 890 "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n"); 891 if (!need_dwarf) { 892 pr_debug("Trying to use symbols.\n"); 893 return 0; 894 } 895 } 896 return ntevs; 897 } 898 899 #define LINEBUF_SIZE 256 900 #define NR_ADDITIONAL_LINES 2 901 902 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num) 903 { 904 char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE]; 905 const char *color = show_num ? "" : PERF_COLOR_BLUE; 906 const char *prefix = NULL; 907 908 do { 909 if (fgets(buf, LINEBUF_SIZE, fp) == NULL) 910 goto error; 911 if (skip) 912 continue; 913 if (!prefix) { 914 prefix = show_num ? "%7d " : " "; 915 color_fprintf(stdout, color, prefix, l); 916 } 917 color_fprintf(stdout, color, "%s", buf); 918 919 } while (strchr(buf, '\n') == NULL); 920 921 return 1; 922 error: 923 if (ferror(fp)) { 924 pr_warning("File read error: %s\n", 925 str_error_r(errno, sbuf, sizeof(sbuf))); 926 return -1; 927 } 928 return 0; 929 } 930 931 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num) 932 { 933 int rv = __show_one_line(fp, l, skip, show_num); 934 if (rv == 0) { 935 pr_warning("Source file is shorter than expected.\n"); 936 rv = -1; 937 } 938 return rv; 939 } 940 941 #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true) 942 #define show_one_line(f,l) _show_one_line(f,l,false,false) 943 #define skip_one_line(f,l) _show_one_line(f,l,true,false) 944 #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false) 945 946 /* 947 * Show line-range always requires debuginfo to find source file and 948 * line number. 949 */ 950 static int __show_line_range(struct line_range *lr, const char *module, 951 bool user) 952 { 953 int l = 1; 954 struct int_node *ln; 955 struct debuginfo *dinfo; 956 FILE *fp; 957 int ret; 958 char *tmp; 959 char sbuf[STRERR_BUFSIZE]; 960 961 /* Search a line range */ 962 dinfo = open_debuginfo(module, NULL, false); 963 if (!dinfo) 964 return -ENOENT; 965 966 ret = debuginfo__find_line_range(dinfo, lr); 967 if (!ret) { /* Not found, retry with an alternative */ 968 ret = get_alternative_line_range(dinfo, lr, module, user); 969 if (!ret) 970 ret = debuginfo__find_line_range(dinfo, lr); 971 } 972 debuginfo__delete(dinfo); 973 if (ret == 0 || ret == -ENOENT) { 974 pr_warning("Specified source line is not found.\n"); 975 return -ENOENT; 976 } else if (ret < 0) { 977 pr_warning("Debuginfo analysis failed.\n"); 978 return ret; 979 } 980 981 /* Convert source file path */ 982 tmp = lr->path; 983 ret = get_real_path(tmp, lr->comp_dir, &lr->path); 984 985 /* Free old path when new path is assigned */ 986 if (tmp != lr->path) 987 free(tmp); 988 989 if (ret < 0) { 990 pr_warning("Failed to find source file path.\n"); 991 return ret; 992 } 993 994 setup_pager(); 995 996 if (lr->function) 997 fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path, 998 lr->start - lr->offset); 999 else 1000 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start); 1001 1002 fp = fopen(lr->path, "r"); 1003 if (fp == NULL) { 1004 pr_warning("Failed to open %s: %s\n", lr->path, 1005 str_error_r(errno, sbuf, sizeof(sbuf))); 1006 return -errno; 1007 } 1008 /* Skip to starting line number */ 1009 while (l < lr->start) { 1010 ret = skip_one_line(fp, l++); 1011 if (ret < 0) 1012 goto end; 1013 } 1014 1015 intlist__for_each_entry(ln, lr->line_list) { 1016 for (; ln->i > l; l++) { 1017 ret = show_one_line(fp, l - lr->offset); 1018 if (ret < 0) 1019 goto end; 1020 } 1021 ret = show_one_line_with_num(fp, l++ - lr->offset); 1022 if (ret < 0) 1023 goto end; 1024 } 1025 1026 if (lr->end == INT_MAX) 1027 lr->end = l + NR_ADDITIONAL_LINES; 1028 while (l <= lr->end) { 1029 ret = show_one_line_or_eof(fp, l++ - lr->offset); 1030 if (ret <= 0) 1031 break; 1032 } 1033 end: 1034 fclose(fp); 1035 return ret; 1036 } 1037 1038 int show_line_range(struct line_range *lr, const char *module, 1039 struct nsinfo *nsi, bool user) 1040 { 1041 int ret; 1042 struct nscookie nsc; 1043 1044 ret = init_probe_symbol_maps(user); 1045 if (ret < 0) 1046 return ret; 1047 nsinfo__mountns_enter(nsi, &nsc); 1048 ret = __show_line_range(lr, module, user); 1049 nsinfo__mountns_exit(&nsc); 1050 exit_probe_symbol_maps(); 1051 1052 return ret; 1053 } 1054 1055 static int show_available_vars_at(struct debuginfo *dinfo, 1056 struct perf_probe_event *pev, 1057 struct strfilter *_filter) 1058 { 1059 char *buf; 1060 int ret, i, nvars; 1061 struct str_node *node; 1062 struct variable_list *vls = NULL, *vl; 1063 struct perf_probe_point tmp; 1064 const char *var; 1065 1066 buf = synthesize_perf_probe_point(&pev->point); 1067 if (!buf) 1068 return -EINVAL; 1069 pr_debug("Searching variables at %s\n", buf); 1070 1071 ret = debuginfo__find_available_vars_at(dinfo, pev, &vls); 1072 if (!ret) { /* Not found, retry with an alternative */ 1073 ret = get_alternative_probe_event(dinfo, pev, &tmp); 1074 if (!ret) { 1075 ret = debuginfo__find_available_vars_at(dinfo, pev, 1076 &vls); 1077 /* Release the old probe_point */ 1078 clear_perf_probe_point(&tmp); 1079 } 1080 } 1081 if (ret <= 0) { 1082 if (ret == 0 || ret == -ENOENT) { 1083 pr_err("Failed to find the address of %s\n", buf); 1084 ret = -ENOENT; 1085 } else 1086 pr_warning("Debuginfo analysis failed.\n"); 1087 goto end; 1088 } 1089 1090 /* Some variables are found */ 1091 fprintf(stdout, "Available variables at %s\n", buf); 1092 for (i = 0; i < ret; i++) { 1093 vl = &vls[i]; 1094 /* 1095 * A probe point might be converted to 1096 * several trace points. 1097 */ 1098 fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol, 1099 vl->point.offset); 1100 zfree(&vl->point.symbol); 1101 nvars = 0; 1102 if (vl->vars) { 1103 strlist__for_each_entry(node, vl->vars) { 1104 var = strchr(node->s, '\t') + 1; 1105 if (strfilter__compare(_filter, var)) { 1106 fprintf(stdout, "\t\t%s\n", node->s); 1107 nvars++; 1108 } 1109 } 1110 strlist__delete(vl->vars); 1111 } 1112 if (nvars == 0) 1113 fprintf(stdout, "\t\t(No matched variables)\n"); 1114 } 1115 free(vls); 1116 end: 1117 free(buf); 1118 return ret; 1119 } 1120 1121 /* Show available variables on given probe point */ 1122 int show_available_vars(struct perf_probe_event *pevs, int npevs, 1123 struct strfilter *_filter) 1124 { 1125 int i, ret = 0; 1126 struct debuginfo *dinfo; 1127 1128 ret = init_probe_symbol_maps(pevs->uprobes); 1129 if (ret < 0) 1130 return ret; 1131 1132 dinfo = open_debuginfo(pevs->target, pevs->nsi, false); 1133 if (!dinfo) { 1134 ret = -ENOENT; 1135 goto out; 1136 } 1137 1138 setup_pager(); 1139 1140 for (i = 0; i < npevs && ret >= 0; i++) 1141 ret = show_available_vars_at(dinfo, &pevs[i], _filter); 1142 1143 debuginfo__delete(dinfo); 1144 out: 1145 exit_probe_symbol_maps(); 1146 return ret; 1147 } 1148 1149 #else /* !HAVE_DWARF_SUPPORT */ 1150 1151 static void debuginfo_cache__exit(void) 1152 { 1153 } 1154 1155 static int 1156 find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused, 1157 struct perf_probe_point *pp __maybe_unused, 1158 bool is_kprobe __maybe_unused) 1159 { 1160 return -ENOSYS; 1161 } 1162 1163 static int try_to_find_probe_trace_events(struct perf_probe_event *pev, 1164 struct probe_trace_event **tevs __maybe_unused) 1165 { 1166 if (perf_probe_event_need_dwarf(pev)) { 1167 pr_warning("Debuginfo-analysis is not supported.\n"); 1168 return -ENOSYS; 1169 } 1170 1171 return 0; 1172 } 1173 1174 int show_line_range(struct line_range *lr __maybe_unused, 1175 const char *module __maybe_unused, 1176 struct nsinfo *nsi __maybe_unused, 1177 bool user __maybe_unused) 1178 { 1179 pr_warning("Debuginfo-analysis is not supported.\n"); 1180 return -ENOSYS; 1181 } 1182 1183 int show_available_vars(struct perf_probe_event *pevs __maybe_unused, 1184 int npevs __maybe_unused, 1185 struct strfilter *filter __maybe_unused) 1186 { 1187 pr_warning("Debuginfo-analysis is not supported.\n"); 1188 return -ENOSYS; 1189 } 1190 #endif 1191 1192 void line_range__clear(struct line_range *lr) 1193 { 1194 zfree(&lr->function); 1195 zfree(&lr->file); 1196 zfree(&lr->path); 1197 zfree(&lr->comp_dir); 1198 intlist__delete(lr->line_list); 1199 } 1200 1201 int line_range__init(struct line_range *lr) 1202 { 1203 memset(lr, 0, sizeof(*lr)); 1204 lr->line_list = intlist__new(NULL); 1205 if (!lr->line_list) 1206 return -ENOMEM; 1207 else 1208 return 0; 1209 } 1210 1211 static int parse_line_num(char **ptr, int *val, const char *what) 1212 { 1213 const char *start = *ptr; 1214 1215 errno = 0; 1216 *val = strtol(*ptr, ptr, 0); 1217 if (errno || *ptr == start) { 1218 semantic_error("'%s' is not a valid number.\n", what); 1219 return -EINVAL; 1220 } 1221 return 0; 1222 } 1223 1224 /* Check the name is good for event, group or function */ 1225 static bool is_c_func_name(const char *name) 1226 { 1227 if (!isalpha(*name) && *name != '_') 1228 return false; 1229 while (*++name != '\0') { 1230 if (!isalpha(*name) && !isdigit(*name) && *name != '_') 1231 return false; 1232 } 1233 return true; 1234 } 1235 1236 /* 1237 * Stuff 'lr' according to the line range described by 'arg'. 1238 * The line range syntax is described by: 1239 * 1240 * SRC[:SLN[+NUM|-ELN]] 1241 * FNC[@SRC][:SLN[+NUM|-ELN]] 1242 */ 1243 int parse_line_range_desc(const char *arg, struct line_range *lr) 1244 { 1245 char *range, *file, *name = strdup(arg); 1246 int err; 1247 1248 if (!name) 1249 return -ENOMEM; 1250 1251 lr->start = 0; 1252 lr->end = INT_MAX; 1253 1254 range = strchr(name, ':'); 1255 if (range) { 1256 *range++ = '\0'; 1257 1258 err = parse_line_num(&range, &lr->start, "start line"); 1259 if (err) 1260 goto err; 1261 1262 if (*range == '+' || *range == '-') { 1263 const char c = *range++; 1264 1265 err = parse_line_num(&range, &lr->end, "end line"); 1266 if (err) 1267 goto err; 1268 1269 if (c == '+') { 1270 lr->end += lr->start; 1271 /* 1272 * Adjust the number of lines here. 1273 * If the number of lines == 1, the 1274 * the end of line should be equal to 1275 * the start of line. 1276 */ 1277 lr->end--; 1278 } 1279 } 1280 1281 pr_debug("Line range is %d to %d\n", lr->start, lr->end); 1282 1283 err = -EINVAL; 1284 if (lr->start > lr->end) { 1285 semantic_error("Start line must be smaller" 1286 " than end line.\n"); 1287 goto err; 1288 } 1289 if (*range != '\0') { 1290 semantic_error("Tailing with invalid str '%s'.\n", range); 1291 goto err; 1292 } 1293 } 1294 1295 file = strchr(name, '@'); 1296 if (file) { 1297 *file = '\0'; 1298 lr->file = strdup(++file); 1299 if (lr->file == NULL) { 1300 err = -ENOMEM; 1301 goto err; 1302 } 1303 lr->function = name; 1304 } else if (strchr(name, '/') || strchr(name, '.')) 1305 lr->file = name; 1306 else if (is_c_func_name(name))/* We reuse it for checking funcname */ 1307 lr->function = name; 1308 else { /* Invalid name */ 1309 semantic_error("'%s' is not a valid function name.\n", name); 1310 err = -EINVAL; 1311 goto err; 1312 } 1313 1314 return 0; 1315 err: 1316 free(name); 1317 return err; 1318 } 1319 1320 static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) 1321 { 1322 char *ptr; 1323 1324 ptr = strpbrk_esc(*arg, ":"); 1325 if (ptr) { 1326 *ptr = '\0'; 1327 if (!pev->sdt && !is_c_func_name(*arg)) 1328 goto ng_name; 1329 pev->group = strdup_esc(*arg); 1330 if (!pev->group) 1331 return -ENOMEM; 1332 *arg = ptr + 1; 1333 } else 1334 pev->group = NULL; 1335 1336 pev->event = strdup_esc(*arg); 1337 if (pev->event == NULL) 1338 return -ENOMEM; 1339 1340 if (!pev->sdt && !is_c_func_name(pev->event)) { 1341 zfree(&pev->event); 1342 ng_name: 1343 zfree(&pev->group); 1344 semantic_error("%s is bad for event name -it must " 1345 "follow C symbol-naming rule.\n", *arg); 1346 return -EINVAL; 1347 } 1348 return 0; 1349 } 1350 1351 /* Parse probepoint definition. */ 1352 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) 1353 { 1354 struct perf_probe_point *pp = &pev->point; 1355 char *ptr, *tmp; 1356 char c, nc = 0; 1357 bool file_spec = false; 1358 int ret; 1359 1360 /* 1361 * <Syntax> 1362 * perf probe [GRP:][EVENT=]SRC[:LN|;PTN] 1363 * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT] 1364 * perf probe %[GRP:]SDT_EVENT 1365 */ 1366 if (!arg) 1367 return -EINVAL; 1368 1369 if (is_sdt_event(arg)) { 1370 pev->sdt = true; 1371 if (arg[0] == '%') 1372 arg++; 1373 } 1374 1375 ptr = strpbrk_esc(arg, ";=@+%"); 1376 if (pev->sdt) { 1377 if (ptr) { 1378 if (*ptr != '@') { 1379 semantic_error("%s must be an SDT name.\n", 1380 arg); 1381 return -EINVAL; 1382 } 1383 /* This must be a target file name or build id */ 1384 tmp = build_id_cache__complement(ptr + 1); 1385 if (tmp) { 1386 pev->target = build_id_cache__origname(tmp); 1387 free(tmp); 1388 } else 1389 pev->target = strdup_esc(ptr + 1); 1390 if (!pev->target) 1391 return -ENOMEM; 1392 *ptr = '\0'; 1393 } 1394 ret = parse_perf_probe_event_name(&arg, pev); 1395 if (ret == 0) { 1396 if (asprintf(&pev->point.function, "%%%s", pev->event) < 0) 1397 ret = -errno; 1398 } 1399 return ret; 1400 } 1401 1402 if (ptr && *ptr == '=') { /* Event name */ 1403 *ptr = '\0'; 1404 tmp = ptr + 1; 1405 ret = parse_perf_probe_event_name(&arg, pev); 1406 if (ret < 0) 1407 return ret; 1408 1409 arg = tmp; 1410 } 1411 1412 /* 1413 * Check arg is function or file name and copy it. 1414 * 1415 * We consider arg to be a file spec if and only if it satisfies 1416 * all of the below criteria:: 1417 * - it does not include any of "+@%", 1418 * - it includes one of ":;", and 1419 * - it has a period '.' in the name. 1420 * 1421 * Otherwise, we consider arg to be a function specification. 1422 */ 1423 if (!strpbrk_esc(arg, "+@%")) { 1424 ptr = strpbrk_esc(arg, ";:"); 1425 /* This is a file spec if it includes a '.' before ; or : */ 1426 if (ptr && memchr(arg, '.', ptr - arg)) 1427 file_spec = true; 1428 } 1429 1430 ptr = strpbrk_esc(arg, ";:+@%"); 1431 if (ptr) { 1432 nc = *ptr; 1433 *ptr++ = '\0'; 1434 } 1435 1436 if (arg[0] == '\0') 1437 tmp = NULL; 1438 else { 1439 tmp = strdup_esc(arg); 1440 if (tmp == NULL) 1441 return -ENOMEM; 1442 } 1443 1444 if (file_spec) 1445 pp->file = tmp; 1446 else { 1447 pp->function = tmp; 1448 1449 /* 1450 * Keep pp->function even if this is absolute address, 1451 * so it can mark whether abs_address is valid. 1452 * Which make 'perf probe lib.bin 0x0' possible. 1453 * 1454 * Note that checking length of tmp is not needed 1455 * because when we access tmp[1] we know tmp[0] is '0', 1456 * so tmp[1] should always valid (but could be '\0'). 1457 */ 1458 if (tmp && !strncmp(tmp, "0x", 2)) { 1459 pp->abs_address = strtoul(pp->function, &tmp, 0); 1460 if (*tmp != '\0') { 1461 semantic_error("Invalid absolute address.\n"); 1462 return -EINVAL; 1463 } 1464 } 1465 } 1466 1467 /* Parse other options */ 1468 while (ptr) { 1469 arg = ptr; 1470 c = nc; 1471 if (c == ';') { /* Lazy pattern must be the last part */ 1472 pp->lazy_line = strdup(arg); /* let leave escapes */ 1473 if (pp->lazy_line == NULL) 1474 return -ENOMEM; 1475 break; 1476 } 1477 ptr = strpbrk_esc(arg, ";:+@%"); 1478 if (ptr) { 1479 nc = *ptr; 1480 *ptr++ = '\0'; 1481 } 1482 switch (c) { 1483 case ':': /* Line number */ 1484 pp->line = strtoul(arg, &tmp, 0); 1485 if (*tmp != '\0') { 1486 semantic_error("There is non-digit char" 1487 " in line number.\n"); 1488 return -EINVAL; 1489 } 1490 break; 1491 case '+': /* Byte offset from a symbol */ 1492 pp->offset = strtoul(arg, &tmp, 0); 1493 if (*tmp != '\0') { 1494 semantic_error("There is non-digit character" 1495 " in offset.\n"); 1496 return -EINVAL; 1497 } 1498 break; 1499 case '@': /* File name */ 1500 if (pp->file) { 1501 semantic_error("SRC@SRC is not allowed.\n"); 1502 return -EINVAL; 1503 } 1504 pp->file = strdup_esc(arg); 1505 if (pp->file == NULL) 1506 return -ENOMEM; 1507 break; 1508 case '%': /* Probe places */ 1509 if (strcmp(arg, "return") == 0) { 1510 pp->retprobe = 1; 1511 } else { /* Others not supported yet */ 1512 semantic_error("%%%s is not supported.\n", arg); 1513 return -ENOTSUP; 1514 } 1515 break; 1516 default: /* Buggy case */ 1517 pr_err("This program has a bug at %s:%d.\n", 1518 __FILE__, __LINE__); 1519 return -ENOTSUP; 1520 break; 1521 } 1522 } 1523 1524 /* Exclusion check */ 1525 if (pp->lazy_line && pp->line) { 1526 semantic_error("Lazy pattern can't be used with" 1527 " line number.\n"); 1528 return -EINVAL; 1529 } 1530 1531 if (pp->lazy_line && pp->offset) { 1532 semantic_error("Lazy pattern can't be used with offset.\n"); 1533 return -EINVAL; 1534 } 1535 1536 if (pp->line && pp->offset) { 1537 semantic_error("Offset can't be used with line number.\n"); 1538 return -EINVAL; 1539 } 1540 1541 if (!pp->line && !pp->lazy_line && pp->file && !pp->function) { 1542 semantic_error("File always requires line number or " 1543 "lazy pattern.\n"); 1544 return -EINVAL; 1545 } 1546 1547 if (pp->offset && !pp->function) { 1548 semantic_error("Offset requires an entry function.\n"); 1549 return -EINVAL; 1550 } 1551 1552 if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) { 1553 semantic_error("Offset/Line/Lazy pattern can't be used with " 1554 "return probe.\n"); 1555 return -EINVAL; 1556 } 1557 1558 pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n", 1559 pp->function, pp->file, pp->line, pp->offset, pp->retprobe, 1560 pp->lazy_line); 1561 return 0; 1562 } 1563 1564 /* Parse perf-probe event argument */ 1565 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg) 1566 { 1567 char *tmp, *goodname; 1568 struct perf_probe_arg_field **fieldp; 1569 1570 pr_debug("parsing arg: %s into ", str); 1571 1572 tmp = strchr(str, '='); 1573 if (tmp) { 1574 arg->name = strndup(str, tmp - str); 1575 if (arg->name == NULL) 1576 return -ENOMEM; 1577 pr_debug("name:%s ", arg->name); 1578 str = tmp + 1; 1579 } 1580 1581 tmp = strchr(str, '@'); 1582 if (tmp && tmp != str && !strcmp(tmp + 1, "user")) { /* user attr */ 1583 if (!user_access_is_supported()) { 1584 semantic_error("ftrace does not support user access\n"); 1585 return -EINVAL; 1586 } 1587 *tmp = '\0'; 1588 arg->user_access = true; 1589 pr_debug("user_access "); 1590 } 1591 1592 tmp = strchr(str, ':'); 1593 if (tmp) { /* Type setting */ 1594 *tmp = '\0'; 1595 arg->type = strdup(tmp + 1); 1596 if (arg->type == NULL) 1597 return -ENOMEM; 1598 pr_debug("type:%s ", arg->type); 1599 } 1600 1601 tmp = strpbrk(str, "-.["); 1602 if (!is_c_varname(str) || !tmp) { 1603 /* A variable, register, symbol or special value */ 1604 arg->var = strdup(str); 1605 if (arg->var == NULL) 1606 return -ENOMEM; 1607 pr_debug("%s\n", arg->var); 1608 return 0; 1609 } 1610 1611 /* Structure fields or array element */ 1612 arg->var = strndup(str, tmp - str); 1613 if (arg->var == NULL) 1614 return -ENOMEM; 1615 goodname = arg->var; 1616 pr_debug("%s, ", arg->var); 1617 fieldp = &arg->field; 1618 1619 do { 1620 *fieldp = zalloc(sizeof(struct perf_probe_arg_field)); 1621 if (*fieldp == NULL) 1622 return -ENOMEM; 1623 if (*tmp == '[') { /* Array */ 1624 str = tmp; 1625 (*fieldp)->index = strtol(str + 1, &tmp, 0); 1626 (*fieldp)->ref = true; 1627 if (*tmp != ']' || tmp == str + 1) { 1628 semantic_error("Array index must be a" 1629 " number.\n"); 1630 return -EINVAL; 1631 } 1632 tmp++; 1633 if (*tmp == '\0') 1634 tmp = NULL; 1635 } else { /* Structure */ 1636 if (*tmp == '.') { 1637 str = tmp + 1; 1638 (*fieldp)->ref = false; 1639 } else if (tmp[1] == '>') { 1640 str = tmp + 2; 1641 (*fieldp)->ref = true; 1642 } else { 1643 semantic_error("Argument parse error: %s\n", 1644 str); 1645 return -EINVAL; 1646 } 1647 tmp = strpbrk(str, "-.["); 1648 } 1649 if (tmp) { 1650 (*fieldp)->name = strndup(str, tmp - str); 1651 if ((*fieldp)->name == NULL) 1652 return -ENOMEM; 1653 if (*str != '[') 1654 goodname = (*fieldp)->name; 1655 pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref); 1656 fieldp = &(*fieldp)->next; 1657 } 1658 } while (tmp); 1659 (*fieldp)->name = strdup(str); 1660 if ((*fieldp)->name == NULL) 1661 return -ENOMEM; 1662 if (*str != '[') 1663 goodname = (*fieldp)->name; 1664 pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref); 1665 1666 /* If no name is specified, set the last field name (not array index)*/ 1667 if (!arg->name) { 1668 arg->name = strdup(goodname); 1669 if (arg->name == NULL) 1670 return -ENOMEM; 1671 } 1672 return 0; 1673 } 1674 1675 /* Parse perf-probe event command */ 1676 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev) 1677 { 1678 char **argv; 1679 int argc, i, ret = 0; 1680 1681 argv = argv_split(cmd, &argc); 1682 if (!argv) { 1683 pr_debug("Failed to split arguments.\n"); 1684 return -ENOMEM; 1685 } 1686 if (argc - 1 > MAX_PROBE_ARGS) { 1687 semantic_error("Too many probe arguments (%d).\n", argc - 1); 1688 ret = -ERANGE; 1689 goto out; 1690 } 1691 /* Parse probe point */ 1692 ret = parse_perf_probe_point(argv[0], pev); 1693 if (ret < 0) 1694 goto out; 1695 1696 /* Generate event name if needed */ 1697 if (!pev->event && pev->point.function && pev->point.line 1698 && !pev->point.lazy_line && !pev->point.offset) { 1699 if (asprintf(&pev->event, "%s_L%d", pev->point.function, 1700 pev->point.line) < 0) 1701 return -ENOMEM; 1702 } 1703 1704 /* Copy arguments and ensure return probe has no C argument */ 1705 pev->nargs = argc - 1; 1706 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); 1707 if (pev->args == NULL) { 1708 ret = -ENOMEM; 1709 goto out; 1710 } 1711 for (i = 0; i < pev->nargs && ret >= 0; i++) { 1712 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]); 1713 if (ret >= 0 && 1714 is_c_varname(pev->args[i].var) && pev->point.retprobe) { 1715 semantic_error("You can't specify local variable for" 1716 " kretprobe.\n"); 1717 ret = -EINVAL; 1718 } 1719 } 1720 out: 1721 argv_free(argv); 1722 1723 return ret; 1724 } 1725 1726 /* Returns true if *any* ARG is either C variable, $params or $vars. */ 1727 bool perf_probe_with_var(struct perf_probe_event *pev) 1728 { 1729 int i = 0; 1730 1731 for (i = 0; i < pev->nargs; i++) 1732 if (is_c_varname(pev->args[i].var) || 1733 !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) || 1734 !strcmp(pev->args[i].var, PROBE_ARG_VARS)) 1735 return true; 1736 return false; 1737 } 1738 1739 /* Return true if this perf_probe_event requires debuginfo */ 1740 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev) 1741 { 1742 if (pev->point.file || pev->point.line || pev->point.lazy_line) 1743 return true; 1744 1745 if (perf_probe_with_var(pev)) 1746 return true; 1747 1748 return false; 1749 } 1750 1751 /* Parse probe_events event into struct probe_point */ 1752 int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev) 1753 { 1754 struct probe_trace_point *tp = &tev->point; 1755 char pr; 1756 char *p; 1757 char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str; 1758 int ret, i, argc; 1759 char **argv; 1760 1761 pr_debug("Parsing probe_events: %s\n", cmd); 1762 argv = argv_split(cmd, &argc); 1763 if (!argv) { 1764 pr_debug("Failed to split arguments.\n"); 1765 return -ENOMEM; 1766 } 1767 if (argc < 2) { 1768 semantic_error("Too few probe arguments.\n"); 1769 ret = -ERANGE; 1770 goto out; 1771 } 1772 1773 /* Scan event and group name. */ 1774 argv0_str = strdup(argv[0]); 1775 if (argv0_str == NULL) { 1776 ret = -ENOMEM; 1777 goto out; 1778 } 1779 fmt1_str = strtok_r(argv0_str, ":", &fmt); 1780 fmt2_str = strtok_r(NULL, "/", &fmt); 1781 fmt3_str = strtok_r(NULL, " \t", &fmt); 1782 if (fmt1_str == NULL || fmt2_str == NULL || fmt3_str == NULL) { 1783 semantic_error("Failed to parse event name: %s\n", argv[0]); 1784 ret = -EINVAL; 1785 goto out; 1786 } 1787 pr = fmt1_str[0]; 1788 tev->group = strdup(fmt2_str); 1789 tev->event = strdup(fmt3_str); 1790 if (tev->group == NULL || tev->event == NULL) { 1791 ret = -ENOMEM; 1792 goto out; 1793 } 1794 pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr); 1795 1796 tp->retprobe = (pr == 'r'); 1797 1798 /* Scan module name(if there), function name and offset */ 1799 p = strchr(argv[1], ':'); 1800 if (p) { 1801 tp->module = strndup(argv[1], p - argv[1]); 1802 if (!tp->module) { 1803 ret = -ENOMEM; 1804 goto out; 1805 } 1806 tev->uprobes = (tp->module[0] == '/'); 1807 p++; 1808 } else 1809 p = argv[1]; 1810 fmt1_str = strtok_r(p, "+", &fmt); 1811 /* only the address started with 0x */ 1812 if (fmt1_str[0] == '0') { 1813 /* 1814 * Fix a special case: 1815 * if address == 0, kernel reports something like: 1816 * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax 1817 * Newer kernel may fix that, but we want to 1818 * support old kernel also. 1819 */ 1820 if (strcmp(fmt1_str, "0x") == 0) { 1821 if (!argv[2] || strcmp(argv[2], "(null)")) { 1822 ret = -EINVAL; 1823 goto out; 1824 } 1825 tp->address = 0; 1826 1827 free(argv[2]); 1828 for (i = 2; argv[i + 1] != NULL; i++) 1829 argv[i] = argv[i + 1]; 1830 1831 argv[i] = NULL; 1832 argc -= 1; 1833 } else 1834 tp->address = strtoul(fmt1_str, NULL, 0); 1835 } else { 1836 /* Only the symbol-based probe has offset */ 1837 tp->symbol = strdup(fmt1_str); 1838 if (tp->symbol == NULL) { 1839 ret = -ENOMEM; 1840 goto out; 1841 } 1842 fmt2_str = strtok_r(NULL, "", &fmt); 1843 if (fmt2_str == NULL) 1844 tp->offset = 0; 1845 else 1846 tp->offset = strtoul(fmt2_str, NULL, 10); 1847 } 1848 1849 if (tev->uprobes) { 1850 fmt2_str = strchr(p, '('); 1851 if (fmt2_str) 1852 tp->ref_ctr_offset = strtoul(fmt2_str + 1, NULL, 0); 1853 } 1854 1855 tev->nargs = argc - 2; 1856 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); 1857 if (tev->args == NULL) { 1858 ret = -ENOMEM; 1859 goto out; 1860 } 1861 for (i = 0; i < tev->nargs; i++) { 1862 p = strchr(argv[i + 2], '='); 1863 if (p) /* We don't need which register is assigned. */ 1864 *p++ = '\0'; 1865 else 1866 p = argv[i + 2]; 1867 tev->args[i].name = strdup(argv[i + 2]); 1868 /* TODO: parse regs and offset */ 1869 tev->args[i].value = strdup(p); 1870 if (tev->args[i].name == NULL || tev->args[i].value == NULL) { 1871 ret = -ENOMEM; 1872 goto out; 1873 } 1874 } 1875 ret = 0; 1876 out: 1877 free(argv0_str); 1878 argv_free(argv); 1879 return ret; 1880 } 1881 1882 /* Compose only probe arg */ 1883 char *synthesize_perf_probe_arg(struct perf_probe_arg *pa) 1884 { 1885 struct perf_probe_arg_field *field = pa->field; 1886 struct strbuf buf; 1887 char *ret = NULL; 1888 int err; 1889 1890 if (strbuf_init(&buf, 64) < 0) 1891 return NULL; 1892 1893 if (pa->name && pa->var) 1894 err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var); 1895 else 1896 err = strbuf_addstr(&buf, pa->name ?: pa->var); 1897 if (err) 1898 goto out; 1899 1900 while (field) { 1901 if (field->name[0] == '[') 1902 err = strbuf_addstr(&buf, field->name); 1903 else 1904 err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".", 1905 field->name); 1906 field = field->next; 1907 if (err) 1908 goto out; 1909 } 1910 1911 if (pa->type) 1912 if (strbuf_addf(&buf, ":%s", pa->type) < 0) 1913 goto out; 1914 1915 ret = strbuf_detach(&buf, NULL); 1916 out: 1917 strbuf_release(&buf); 1918 return ret; 1919 } 1920 1921 /* Compose only probe point (not argument) */ 1922 char *synthesize_perf_probe_point(struct perf_probe_point *pp) 1923 { 1924 struct strbuf buf; 1925 char *tmp, *ret = NULL; 1926 int len, err = 0; 1927 1928 if (strbuf_init(&buf, 64) < 0) 1929 return NULL; 1930 1931 if (pp->function) { 1932 if (strbuf_addstr(&buf, pp->function) < 0) 1933 goto out; 1934 if (pp->offset) 1935 err = strbuf_addf(&buf, "+%lu", pp->offset); 1936 else if (pp->line) 1937 err = strbuf_addf(&buf, ":%d", pp->line); 1938 else if (pp->retprobe) 1939 err = strbuf_addstr(&buf, "%return"); 1940 if (err) 1941 goto out; 1942 } 1943 if (pp->file) { 1944 tmp = pp->file; 1945 len = strlen(tmp); 1946 if (len > 30) { 1947 tmp = strchr(pp->file + len - 30, '/'); 1948 tmp = tmp ? tmp + 1 : pp->file + len - 30; 1949 } 1950 err = strbuf_addf(&buf, "@%s", tmp); 1951 if (!err && !pp->function && pp->line) 1952 err = strbuf_addf(&buf, ":%d", pp->line); 1953 } 1954 if (!err) 1955 ret = strbuf_detach(&buf, NULL); 1956 out: 1957 strbuf_release(&buf); 1958 return ret; 1959 } 1960 1961 char *synthesize_perf_probe_command(struct perf_probe_event *pev) 1962 { 1963 struct strbuf buf; 1964 char *tmp, *ret = NULL; 1965 int i; 1966 1967 if (strbuf_init(&buf, 64)) 1968 return NULL; 1969 if (pev->event) 1970 if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP, 1971 pev->event) < 0) 1972 goto out; 1973 1974 tmp = synthesize_perf_probe_point(&pev->point); 1975 if (!tmp || strbuf_addstr(&buf, tmp) < 0) 1976 goto out; 1977 free(tmp); 1978 1979 for (i = 0; i < pev->nargs; i++) { 1980 tmp = synthesize_perf_probe_arg(pev->args + i); 1981 if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0) 1982 goto out; 1983 free(tmp); 1984 } 1985 1986 ret = strbuf_detach(&buf, NULL); 1987 out: 1988 strbuf_release(&buf); 1989 return ret; 1990 } 1991 1992 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref, 1993 struct strbuf *buf, int depth) 1994 { 1995 int err; 1996 if (ref->next) { 1997 depth = __synthesize_probe_trace_arg_ref(ref->next, buf, 1998 depth + 1); 1999 if (depth < 0) 2000 return depth; 2001 } 2002 if (ref->user_access) 2003 err = strbuf_addf(buf, "%s%ld(", "+u", ref->offset); 2004 else 2005 err = strbuf_addf(buf, "%+ld(", ref->offset); 2006 return (err < 0) ? err : depth; 2007 } 2008 2009 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg, 2010 struct strbuf *buf) 2011 { 2012 struct probe_trace_arg_ref *ref = arg->ref; 2013 int depth = 0, err; 2014 2015 /* Argument name or separator */ 2016 if (arg->name) 2017 err = strbuf_addf(buf, " %s=", arg->name); 2018 else 2019 err = strbuf_addch(buf, ' '); 2020 if (err) 2021 return err; 2022 2023 /* Special case: @XXX */ 2024 if (arg->value[0] == '@' && arg->ref) 2025 ref = ref->next; 2026 2027 /* Dereferencing arguments */ 2028 if (ref) { 2029 depth = __synthesize_probe_trace_arg_ref(ref, buf, 1); 2030 if (depth < 0) 2031 return depth; 2032 } 2033 2034 /* Print argument value */ 2035 if (arg->value[0] == '@' && arg->ref) 2036 err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset); 2037 else 2038 err = strbuf_addstr(buf, arg->value); 2039 2040 /* Closing */ 2041 while (!err && depth--) 2042 err = strbuf_addch(buf, ')'); 2043 2044 /* Print argument type */ 2045 if (!err && arg->type) 2046 err = strbuf_addf(buf, ":%s", arg->type); 2047 2048 return err; 2049 } 2050 2051 static int 2052 synthesize_uprobe_trace_def(struct probe_trace_event *tev, struct strbuf *buf) 2053 { 2054 struct probe_trace_point *tp = &tev->point; 2055 int err; 2056 2057 err = strbuf_addf(buf, "%s:0x%lx", tp->module, tp->address); 2058 2059 if (err >= 0 && tp->ref_ctr_offset) { 2060 if (!uprobe_ref_ctr_is_supported()) 2061 return -1; 2062 err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset); 2063 } 2064 return err >= 0 ? 0 : -1; 2065 } 2066 2067 char *synthesize_probe_trace_command(struct probe_trace_event *tev) 2068 { 2069 struct probe_trace_point *tp = &tev->point; 2070 struct strbuf buf; 2071 char *ret = NULL; 2072 int i, err; 2073 2074 /* Uprobes must have tp->module */ 2075 if (tev->uprobes && !tp->module) 2076 return NULL; 2077 2078 if (strbuf_init(&buf, 32) < 0) 2079 return NULL; 2080 2081 if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p', 2082 tev->group, tev->event) < 0) 2083 goto error; 2084 /* 2085 * If tp->address == 0, then this point must be a 2086 * absolute address uprobe. 2087 * try_to_find_absolute_address() should have made 2088 * tp->symbol to "0x0". 2089 */ 2090 if (tev->uprobes && !tp->address) { 2091 if (!tp->symbol || strcmp(tp->symbol, "0x0")) 2092 goto error; 2093 } 2094 2095 /* Use the tp->address for uprobes */ 2096 if (tev->uprobes) { 2097 err = synthesize_uprobe_trace_def(tev, &buf); 2098 } else if (!strncmp(tp->symbol, "0x", 2)) { 2099 /* Absolute address. See try_to_find_absolute_address() */ 2100 err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "", 2101 tp->module ? ":" : "", tp->address); 2102 } else { 2103 err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "", 2104 tp->module ? ":" : "", tp->symbol, tp->offset); 2105 } 2106 2107 if (err) 2108 goto error; 2109 2110 for (i = 0; i < tev->nargs; i++) 2111 if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0) 2112 goto error; 2113 2114 ret = strbuf_detach(&buf, NULL); 2115 error: 2116 strbuf_release(&buf); 2117 return ret; 2118 } 2119 2120 static int find_perf_probe_point_from_map(struct probe_trace_point *tp, 2121 struct perf_probe_point *pp, 2122 bool is_kprobe) 2123 { 2124 struct symbol *sym = NULL; 2125 struct map *map = NULL; 2126 u64 addr = tp->address; 2127 int ret = -ENOENT; 2128 2129 if (!is_kprobe) { 2130 map = dso__new_map(tp->module); 2131 if (!map) 2132 goto out; 2133 sym = map__find_symbol(map, addr); 2134 } else { 2135 if (tp->symbol && !addr) { 2136 if (kernel_get_symbol_address_by_name(tp->symbol, 2137 &addr, true, false) < 0) 2138 goto out; 2139 } 2140 if (addr) { 2141 addr += tp->offset; 2142 sym = machine__find_kernel_symbol(host_machine, addr, &map); 2143 } 2144 } 2145 2146 if (!sym) 2147 goto out; 2148 2149 pp->retprobe = tp->retprobe; 2150 pp->offset = addr - map->unmap_ip(map, sym->start); 2151 pp->function = strdup(sym->name); 2152 ret = pp->function ? 0 : -ENOMEM; 2153 2154 out: 2155 if (map && !is_kprobe) { 2156 map__put(map); 2157 } 2158 2159 return ret; 2160 } 2161 2162 static int convert_to_perf_probe_point(struct probe_trace_point *tp, 2163 struct perf_probe_point *pp, 2164 bool is_kprobe) 2165 { 2166 char buf[128]; 2167 int ret; 2168 2169 ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe); 2170 if (!ret) 2171 return 0; 2172 ret = find_perf_probe_point_from_map(tp, pp, is_kprobe); 2173 if (!ret) 2174 return 0; 2175 2176 pr_debug("Failed to find probe point from both of dwarf and map.\n"); 2177 2178 if (tp->symbol) { 2179 pp->function = strdup(tp->symbol); 2180 pp->offset = tp->offset; 2181 } else { 2182 ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address); 2183 if (ret < 0) 2184 return ret; 2185 pp->function = strdup(buf); 2186 pp->offset = 0; 2187 } 2188 if (pp->function == NULL) 2189 return -ENOMEM; 2190 2191 pp->retprobe = tp->retprobe; 2192 2193 return 0; 2194 } 2195 2196 static int convert_to_perf_probe_event(struct probe_trace_event *tev, 2197 struct perf_probe_event *pev, bool is_kprobe) 2198 { 2199 struct strbuf buf = STRBUF_INIT; 2200 int i, ret; 2201 2202 /* Convert event/group name */ 2203 pev->event = strdup(tev->event); 2204 pev->group = strdup(tev->group); 2205 if (pev->event == NULL || pev->group == NULL) 2206 return -ENOMEM; 2207 2208 /* Convert trace_point to probe_point */ 2209 ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe); 2210 if (ret < 0) 2211 return ret; 2212 2213 /* Convert trace_arg to probe_arg */ 2214 pev->nargs = tev->nargs; 2215 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); 2216 if (pev->args == NULL) 2217 return -ENOMEM; 2218 for (i = 0; i < tev->nargs && ret >= 0; i++) { 2219 if (tev->args[i].name) 2220 pev->args[i].name = strdup(tev->args[i].name); 2221 else { 2222 if ((ret = strbuf_init(&buf, 32)) < 0) 2223 goto error; 2224 ret = synthesize_probe_trace_arg(&tev->args[i], &buf); 2225 pev->args[i].name = strbuf_detach(&buf, NULL); 2226 } 2227 if (pev->args[i].name == NULL && ret >= 0) 2228 ret = -ENOMEM; 2229 } 2230 error: 2231 if (ret < 0) 2232 clear_perf_probe_event(pev); 2233 2234 return ret; 2235 } 2236 2237 void clear_perf_probe_event(struct perf_probe_event *pev) 2238 { 2239 struct perf_probe_arg_field *field, *next; 2240 int i; 2241 2242 zfree(&pev->event); 2243 zfree(&pev->group); 2244 zfree(&pev->target); 2245 clear_perf_probe_point(&pev->point); 2246 2247 for (i = 0; i < pev->nargs; i++) { 2248 zfree(&pev->args[i].name); 2249 zfree(&pev->args[i].var); 2250 zfree(&pev->args[i].type); 2251 field = pev->args[i].field; 2252 while (field) { 2253 next = field->next; 2254 zfree(&field->name); 2255 free(field); 2256 field = next; 2257 } 2258 } 2259 pev->nargs = 0; 2260 zfree(&pev->args); 2261 } 2262 2263 #define strdup_or_goto(str, label) \ 2264 ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; }) 2265 2266 static int perf_probe_point__copy(struct perf_probe_point *dst, 2267 struct perf_probe_point *src) 2268 { 2269 dst->file = strdup_or_goto(src->file, out_err); 2270 dst->function = strdup_or_goto(src->function, out_err); 2271 dst->lazy_line = strdup_or_goto(src->lazy_line, out_err); 2272 dst->line = src->line; 2273 dst->retprobe = src->retprobe; 2274 dst->offset = src->offset; 2275 return 0; 2276 2277 out_err: 2278 clear_perf_probe_point(dst); 2279 return -ENOMEM; 2280 } 2281 2282 static int perf_probe_arg__copy(struct perf_probe_arg *dst, 2283 struct perf_probe_arg *src) 2284 { 2285 struct perf_probe_arg_field *field, **ppfield; 2286 2287 dst->name = strdup_or_goto(src->name, out_err); 2288 dst->var = strdup_or_goto(src->var, out_err); 2289 dst->type = strdup_or_goto(src->type, out_err); 2290 2291 field = src->field; 2292 ppfield = &(dst->field); 2293 while (field) { 2294 *ppfield = zalloc(sizeof(*field)); 2295 if (!*ppfield) 2296 goto out_err; 2297 (*ppfield)->name = strdup_or_goto(field->name, out_err); 2298 (*ppfield)->index = field->index; 2299 (*ppfield)->ref = field->ref; 2300 field = field->next; 2301 ppfield = &((*ppfield)->next); 2302 } 2303 return 0; 2304 out_err: 2305 return -ENOMEM; 2306 } 2307 2308 int perf_probe_event__copy(struct perf_probe_event *dst, 2309 struct perf_probe_event *src) 2310 { 2311 int i; 2312 2313 dst->event = strdup_or_goto(src->event, out_err); 2314 dst->group = strdup_or_goto(src->group, out_err); 2315 dst->target = strdup_or_goto(src->target, out_err); 2316 dst->uprobes = src->uprobes; 2317 2318 if (perf_probe_point__copy(&dst->point, &src->point) < 0) 2319 goto out_err; 2320 2321 dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs); 2322 if (!dst->args) 2323 goto out_err; 2324 dst->nargs = src->nargs; 2325 2326 for (i = 0; i < src->nargs; i++) 2327 if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0) 2328 goto out_err; 2329 return 0; 2330 2331 out_err: 2332 clear_perf_probe_event(dst); 2333 return -ENOMEM; 2334 } 2335 2336 void clear_probe_trace_event(struct probe_trace_event *tev) 2337 { 2338 struct probe_trace_arg_ref *ref, *next; 2339 int i; 2340 2341 zfree(&tev->event); 2342 zfree(&tev->group); 2343 zfree(&tev->point.symbol); 2344 zfree(&tev->point.realname); 2345 zfree(&tev->point.module); 2346 for (i = 0; i < tev->nargs; i++) { 2347 zfree(&tev->args[i].name); 2348 zfree(&tev->args[i].value); 2349 zfree(&tev->args[i].type); 2350 ref = tev->args[i].ref; 2351 while (ref) { 2352 next = ref->next; 2353 free(ref); 2354 ref = next; 2355 } 2356 } 2357 zfree(&tev->args); 2358 tev->nargs = 0; 2359 } 2360 2361 struct kprobe_blacklist_node { 2362 struct list_head list; 2363 unsigned long start; 2364 unsigned long end; 2365 char *symbol; 2366 }; 2367 2368 static void kprobe_blacklist__delete(struct list_head *blacklist) 2369 { 2370 struct kprobe_blacklist_node *node; 2371 2372 while (!list_empty(blacklist)) { 2373 node = list_first_entry(blacklist, 2374 struct kprobe_blacklist_node, list); 2375 list_del_init(&node->list); 2376 zfree(&node->symbol); 2377 free(node); 2378 } 2379 } 2380 2381 static int kprobe_blacklist__load(struct list_head *blacklist) 2382 { 2383 struct kprobe_blacklist_node *node; 2384 const char *__debugfs = debugfs__mountpoint(); 2385 char buf[PATH_MAX], *p; 2386 FILE *fp; 2387 int ret; 2388 2389 if (__debugfs == NULL) 2390 return -ENOTSUP; 2391 2392 ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs); 2393 if (ret < 0) 2394 return ret; 2395 2396 fp = fopen(buf, "r"); 2397 if (!fp) 2398 return -errno; 2399 2400 ret = 0; 2401 while (fgets(buf, PATH_MAX, fp)) { 2402 node = zalloc(sizeof(*node)); 2403 if (!node) { 2404 ret = -ENOMEM; 2405 break; 2406 } 2407 INIT_LIST_HEAD(&node->list); 2408 list_add_tail(&node->list, blacklist); 2409 if (sscanf(buf, "0x%lx-0x%lx", &node->start, &node->end) != 2) { 2410 ret = -EINVAL; 2411 break; 2412 } 2413 p = strchr(buf, '\t'); 2414 if (p) { 2415 p++; 2416 if (p[strlen(p) - 1] == '\n') 2417 p[strlen(p) - 1] = '\0'; 2418 } else 2419 p = (char *)"unknown"; 2420 node->symbol = strdup(p); 2421 if (!node->symbol) { 2422 ret = -ENOMEM; 2423 break; 2424 } 2425 pr_debug2("Blacklist: 0x%lx-0x%lx, %s\n", 2426 node->start, node->end, node->symbol); 2427 ret++; 2428 } 2429 if (ret < 0) 2430 kprobe_blacklist__delete(blacklist); 2431 fclose(fp); 2432 2433 return ret; 2434 } 2435 2436 static struct kprobe_blacklist_node * 2437 kprobe_blacklist__find_by_address(struct list_head *blacklist, 2438 unsigned long address) 2439 { 2440 struct kprobe_blacklist_node *node; 2441 2442 list_for_each_entry(node, blacklist, list) { 2443 if (node->start <= address && address < node->end) 2444 return node; 2445 } 2446 2447 return NULL; 2448 } 2449 2450 static LIST_HEAD(kprobe_blacklist); 2451 2452 static void kprobe_blacklist__init(void) 2453 { 2454 if (!list_empty(&kprobe_blacklist)) 2455 return; 2456 2457 if (kprobe_blacklist__load(&kprobe_blacklist) < 0) 2458 pr_debug("No kprobe blacklist support, ignored\n"); 2459 } 2460 2461 static void kprobe_blacklist__release(void) 2462 { 2463 kprobe_blacklist__delete(&kprobe_blacklist); 2464 } 2465 2466 static bool kprobe_blacklist__listed(unsigned long address) 2467 { 2468 return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address); 2469 } 2470 2471 static int perf_probe_event__sprintf(const char *group, const char *event, 2472 struct perf_probe_event *pev, 2473 const char *module, 2474 struct strbuf *result) 2475 { 2476 int i, ret; 2477 char *buf; 2478 2479 if (asprintf(&buf, "%s:%s", group, event) < 0) 2480 return -errno; 2481 ret = strbuf_addf(result, " %-20s (on ", buf); 2482 free(buf); 2483 if (ret) 2484 return ret; 2485 2486 /* Synthesize only event probe point */ 2487 buf = synthesize_perf_probe_point(&pev->point); 2488 if (!buf) 2489 return -ENOMEM; 2490 ret = strbuf_addstr(result, buf); 2491 free(buf); 2492 2493 if (!ret && module) 2494 ret = strbuf_addf(result, " in %s", module); 2495 2496 if (!ret && pev->nargs > 0) { 2497 ret = strbuf_add(result, " with", 5); 2498 for (i = 0; !ret && i < pev->nargs; i++) { 2499 buf = synthesize_perf_probe_arg(&pev->args[i]); 2500 if (!buf) 2501 return -ENOMEM; 2502 ret = strbuf_addf(result, " %s", buf); 2503 free(buf); 2504 } 2505 } 2506 if (!ret) 2507 ret = strbuf_addch(result, ')'); 2508 2509 return ret; 2510 } 2511 2512 /* Show an event */ 2513 int show_perf_probe_event(const char *group, const char *event, 2514 struct perf_probe_event *pev, 2515 const char *module, bool use_stdout) 2516 { 2517 struct strbuf buf = STRBUF_INIT; 2518 int ret; 2519 2520 ret = perf_probe_event__sprintf(group, event, pev, module, &buf); 2521 if (ret >= 0) { 2522 if (use_stdout) 2523 printf("%s\n", buf.buf); 2524 else 2525 pr_info("%s\n", buf.buf); 2526 } 2527 strbuf_release(&buf); 2528 2529 return ret; 2530 } 2531 2532 static bool filter_probe_trace_event(struct probe_trace_event *tev, 2533 struct strfilter *filter) 2534 { 2535 char tmp[128]; 2536 2537 /* At first, check the event name itself */ 2538 if (strfilter__compare(filter, tev->event)) 2539 return true; 2540 2541 /* Next, check the combination of name and group */ 2542 if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0) 2543 return false; 2544 return strfilter__compare(filter, tmp); 2545 } 2546 2547 static int __show_perf_probe_events(int fd, bool is_kprobe, 2548 struct strfilter *filter) 2549 { 2550 int ret = 0; 2551 struct probe_trace_event tev; 2552 struct perf_probe_event pev; 2553 struct strlist *rawlist; 2554 struct str_node *ent; 2555 2556 memset(&tev, 0, sizeof(tev)); 2557 memset(&pev, 0, sizeof(pev)); 2558 2559 rawlist = probe_file__get_rawlist(fd); 2560 if (!rawlist) 2561 return -ENOMEM; 2562 2563 strlist__for_each_entry(ent, rawlist) { 2564 ret = parse_probe_trace_command(ent->s, &tev); 2565 if (ret >= 0) { 2566 if (!filter_probe_trace_event(&tev, filter)) 2567 goto next; 2568 ret = convert_to_perf_probe_event(&tev, &pev, 2569 is_kprobe); 2570 if (ret < 0) 2571 goto next; 2572 ret = show_perf_probe_event(pev.group, pev.event, 2573 &pev, tev.point.module, 2574 true); 2575 } 2576 next: 2577 clear_perf_probe_event(&pev); 2578 clear_probe_trace_event(&tev); 2579 if (ret < 0) 2580 break; 2581 } 2582 strlist__delete(rawlist); 2583 /* Cleanup cached debuginfo if needed */ 2584 debuginfo_cache__exit(); 2585 2586 return ret; 2587 } 2588 2589 /* List up current perf-probe events */ 2590 int show_perf_probe_events(struct strfilter *filter) 2591 { 2592 int kp_fd, up_fd, ret; 2593 2594 setup_pager(); 2595 2596 if (probe_conf.cache) 2597 return probe_cache__show_all_caches(filter); 2598 2599 ret = init_probe_symbol_maps(false); 2600 if (ret < 0) 2601 return ret; 2602 2603 ret = probe_file__open_both(&kp_fd, &up_fd, 0); 2604 if (ret < 0) 2605 return ret; 2606 2607 if (kp_fd >= 0) 2608 ret = __show_perf_probe_events(kp_fd, true, filter); 2609 if (up_fd >= 0 && ret >= 0) 2610 ret = __show_perf_probe_events(up_fd, false, filter); 2611 if (kp_fd > 0) 2612 close(kp_fd); 2613 if (up_fd > 0) 2614 close(up_fd); 2615 exit_probe_symbol_maps(); 2616 2617 return ret; 2618 } 2619 2620 static int get_new_event_name(char *buf, size_t len, const char *base, 2621 struct strlist *namelist, bool ret_event, 2622 bool allow_suffix) 2623 { 2624 int i, ret; 2625 char *p, *nbase; 2626 2627 if (*base == '.') 2628 base++; 2629 nbase = strdup(base); 2630 if (!nbase) 2631 return -ENOMEM; 2632 2633 /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */ 2634 p = strpbrk(nbase, ".@"); 2635 if (p && p != nbase) 2636 *p = '\0'; 2637 2638 /* Try no suffix number */ 2639 ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : ""); 2640 if (ret < 0) { 2641 pr_debug("snprintf() failed: %d\n", ret); 2642 goto out; 2643 } 2644 if (!strlist__has_entry(namelist, buf)) 2645 goto out; 2646 2647 if (!allow_suffix) { 2648 pr_warning("Error: event \"%s\" already exists.\n" 2649 " Hint: Remove existing event by 'perf probe -d'\n" 2650 " or force duplicates by 'perf probe -f'\n" 2651 " or set 'force=yes' in BPF source.\n", 2652 buf); 2653 ret = -EEXIST; 2654 goto out; 2655 } 2656 2657 /* Try to add suffix */ 2658 for (i = 1; i < MAX_EVENT_INDEX; i++) { 2659 ret = e_snprintf(buf, len, "%s_%d", nbase, i); 2660 if (ret < 0) { 2661 pr_debug("snprintf() failed: %d\n", ret); 2662 goto out; 2663 } 2664 if (!strlist__has_entry(namelist, buf)) 2665 break; 2666 } 2667 if (i == MAX_EVENT_INDEX) { 2668 pr_warning("Too many events are on the same function.\n"); 2669 ret = -ERANGE; 2670 } 2671 2672 out: 2673 free(nbase); 2674 2675 /* Final validation */ 2676 if (ret >= 0 && !is_c_func_name(buf)) { 2677 pr_warning("Internal error: \"%s\" is an invalid event name.\n", 2678 buf); 2679 ret = -EINVAL; 2680 } 2681 2682 return ret; 2683 } 2684 2685 /* Warn if the current kernel's uprobe implementation is old */ 2686 static void warn_uprobe_event_compat(struct probe_trace_event *tev) 2687 { 2688 int i; 2689 char *buf = synthesize_probe_trace_command(tev); 2690 struct probe_trace_point *tp = &tev->point; 2691 2692 if (tp->ref_ctr_offset && !uprobe_ref_ctr_is_supported()) { 2693 pr_warning("A semaphore is associated with %s:%s and " 2694 "seems your kernel doesn't support it.\n", 2695 tev->group, tev->event); 2696 } 2697 2698 /* Old uprobe event doesn't support memory dereference */ 2699 if (!tev->uprobes || tev->nargs == 0 || !buf) 2700 goto out; 2701 2702 for (i = 0; i < tev->nargs; i++) 2703 if (strglobmatch(tev->args[i].value, "[$@+-]*")) { 2704 pr_warning("Please upgrade your kernel to at least " 2705 "3.14 to have access to feature %s\n", 2706 tev->args[i].value); 2707 break; 2708 } 2709 out: 2710 free(buf); 2711 } 2712 2713 /* Set new name from original perf_probe_event and namelist */ 2714 static int probe_trace_event__set_name(struct probe_trace_event *tev, 2715 struct perf_probe_event *pev, 2716 struct strlist *namelist, 2717 bool allow_suffix) 2718 { 2719 const char *event, *group; 2720 char buf[64]; 2721 int ret; 2722 2723 /* If probe_event or trace_event already have the name, reuse it */ 2724 if (pev->event && !pev->sdt) 2725 event = pev->event; 2726 else if (tev->event) 2727 event = tev->event; 2728 else { 2729 /* Or generate new one from probe point */ 2730 if (pev->point.function && 2731 (strncmp(pev->point.function, "0x", 2) != 0) && 2732 !strisglob(pev->point.function)) 2733 event = pev->point.function; 2734 else 2735 event = tev->point.realname; 2736 } 2737 if (pev->group && !pev->sdt) 2738 group = pev->group; 2739 else if (tev->group) 2740 group = tev->group; 2741 else 2742 group = PERFPROBE_GROUP; 2743 2744 /* Get an unused new event name */ 2745 ret = get_new_event_name(buf, 64, event, namelist, 2746 tev->point.retprobe, allow_suffix); 2747 if (ret < 0) 2748 return ret; 2749 2750 event = buf; 2751 2752 tev->event = strdup(event); 2753 tev->group = strdup(group); 2754 if (tev->event == NULL || tev->group == NULL) 2755 return -ENOMEM; 2756 2757 /* 2758 * Add new event name to namelist if multiprobe event is NOT 2759 * supported, since we have to use new event name for following 2760 * probes in that case. 2761 */ 2762 if (!multiprobe_event_is_supported()) 2763 strlist__add(namelist, event); 2764 return 0; 2765 } 2766 2767 static int __open_probe_file_and_namelist(bool uprobe, 2768 struct strlist **namelist) 2769 { 2770 int fd; 2771 2772 fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0)); 2773 if (fd < 0) 2774 return fd; 2775 2776 /* Get current event names */ 2777 *namelist = probe_file__get_namelist(fd); 2778 if (!(*namelist)) { 2779 pr_debug("Failed to get current event list.\n"); 2780 close(fd); 2781 return -ENOMEM; 2782 } 2783 return fd; 2784 } 2785 2786 static int __add_probe_trace_events(struct perf_probe_event *pev, 2787 struct probe_trace_event *tevs, 2788 int ntevs, bool allow_suffix) 2789 { 2790 int i, fd[2] = {-1, -1}, up, ret; 2791 struct probe_trace_event *tev = NULL; 2792 struct probe_cache *cache = NULL; 2793 struct strlist *namelist[2] = {NULL, NULL}; 2794 struct nscookie nsc; 2795 2796 up = pev->uprobes ? 1 : 0; 2797 fd[up] = __open_probe_file_and_namelist(up, &namelist[up]); 2798 if (fd[up] < 0) 2799 return fd[up]; 2800 2801 ret = 0; 2802 for (i = 0; i < ntevs; i++) { 2803 tev = &tevs[i]; 2804 up = tev->uprobes ? 1 : 0; 2805 if (fd[up] == -1) { /* Open the kprobe/uprobe_events */ 2806 fd[up] = __open_probe_file_and_namelist(up, 2807 &namelist[up]); 2808 if (fd[up] < 0) 2809 goto close_out; 2810 } 2811 /* Skip if the symbol is out of .text or blacklisted */ 2812 if (!tev->point.symbol && !pev->uprobes) 2813 continue; 2814 2815 /* Set new name for tev (and update namelist) */ 2816 ret = probe_trace_event__set_name(tev, pev, namelist[up], 2817 allow_suffix); 2818 if (ret < 0) 2819 break; 2820 2821 nsinfo__mountns_enter(pev->nsi, &nsc); 2822 ret = probe_file__add_event(fd[up], tev); 2823 nsinfo__mountns_exit(&nsc); 2824 if (ret < 0) 2825 break; 2826 2827 /* 2828 * Probes after the first probe which comes from same 2829 * user input are always allowed to add suffix, because 2830 * there might be several addresses corresponding to 2831 * one code line. 2832 */ 2833 allow_suffix = true; 2834 } 2835 if (ret == -EINVAL && pev->uprobes) 2836 warn_uprobe_event_compat(tev); 2837 if (ret == 0 && probe_conf.cache) { 2838 cache = probe_cache__new(pev->target, pev->nsi); 2839 if (!cache || 2840 probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 || 2841 probe_cache__commit(cache) < 0) 2842 pr_warning("Failed to add event to probe cache\n"); 2843 probe_cache__delete(cache); 2844 } 2845 2846 close_out: 2847 for (up = 0; up < 2; up++) { 2848 strlist__delete(namelist[up]); 2849 if (fd[up] >= 0) 2850 close(fd[up]); 2851 } 2852 return ret; 2853 } 2854 2855 static int find_probe_functions(struct map *map, char *name, 2856 struct symbol **syms) 2857 { 2858 int found = 0; 2859 struct symbol *sym; 2860 struct rb_node *tmp; 2861 const char *norm, *ver; 2862 char *buf = NULL; 2863 bool cut_version = true; 2864 2865 if (map__load(map) < 0) 2866 return 0; 2867 2868 /* If user gives a version, don't cut off the version from symbols */ 2869 if (strchr(name, '@')) 2870 cut_version = false; 2871 2872 map__for_each_symbol(map, sym, tmp) { 2873 norm = arch__normalize_symbol_name(sym->name); 2874 if (!norm) 2875 continue; 2876 2877 if (cut_version) { 2878 /* We don't care about default symbol or not */ 2879 ver = strchr(norm, '@'); 2880 if (ver) { 2881 buf = strndup(norm, ver - norm); 2882 if (!buf) 2883 return -ENOMEM; 2884 norm = buf; 2885 } 2886 } 2887 2888 if (strglobmatch(norm, name)) { 2889 found++; 2890 if (syms && found < probe_conf.max_probes) 2891 syms[found - 1] = sym; 2892 } 2893 if (buf) 2894 zfree(&buf); 2895 } 2896 2897 return found; 2898 } 2899 2900 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, 2901 struct probe_trace_event *tev __maybe_unused, 2902 struct map *map __maybe_unused, 2903 struct symbol *sym __maybe_unused) { } 2904 2905 /* 2906 * Find probe function addresses from map. 2907 * Return an error or the number of found probe_trace_event 2908 */ 2909 static int find_probe_trace_events_from_map(struct perf_probe_event *pev, 2910 struct probe_trace_event **tevs) 2911 { 2912 struct map *map = NULL; 2913 struct ref_reloc_sym *reloc_sym = NULL; 2914 struct symbol *sym; 2915 struct symbol **syms = NULL; 2916 struct probe_trace_event *tev; 2917 struct perf_probe_point *pp = &pev->point; 2918 struct probe_trace_point *tp; 2919 int num_matched_functions; 2920 int ret, i, j, skipped = 0; 2921 char *mod_name; 2922 2923 map = get_target_map(pev->target, pev->nsi, pev->uprobes); 2924 if (!map) { 2925 ret = -EINVAL; 2926 goto out; 2927 } 2928 2929 syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes); 2930 if (!syms) { 2931 ret = -ENOMEM; 2932 goto out; 2933 } 2934 2935 /* 2936 * Load matched symbols: Since the different local symbols may have 2937 * same name but different addresses, this lists all the symbols. 2938 */ 2939 num_matched_functions = find_probe_functions(map, pp->function, syms); 2940 if (num_matched_functions <= 0) { 2941 pr_err("Failed to find symbol %s in %s\n", pp->function, 2942 pev->target ? : "kernel"); 2943 ret = -ENOENT; 2944 goto out; 2945 } else if (num_matched_functions > probe_conf.max_probes) { 2946 pr_err("Too many functions matched in %s\n", 2947 pev->target ? : "kernel"); 2948 ret = -E2BIG; 2949 goto out; 2950 } 2951 2952 /* Note that the symbols in the kmodule are not relocated */ 2953 if (!pev->uprobes && !pev->target && 2954 (!pp->retprobe || kretprobe_offset_is_supported())) { 2955 reloc_sym = kernel_get_ref_reloc_sym(NULL); 2956 if (!reloc_sym) { 2957 pr_warning("Relocated base symbol is not found!\n"); 2958 ret = -EINVAL; 2959 goto out; 2960 } 2961 } 2962 2963 /* Setup result trace-probe-events */ 2964 *tevs = zalloc(sizeof(*tev) * num_matched_functions); 2965 if (!*tevs) { 2966 ret = -ENOMEM; 2967 goto out; 2968 } 2969 2970 ret = 0; 2971 2972 for (j = 0; j < num_matched_functions; j++) { 2973 sym = syms[j]; 2974 2975 /* There can be duplicated symbols in the map */ 2976 for (i = 0; i < j; i++) 2977 if (sym->start == syms[i]->start) { 2978 pr_debug("Found duplicated symbol %s @ %" PRIx64 "\n", 2979 sym->name, sym->start); 2980 break; 2981 } 2982 if (i != j) 2983 continue; 2984 2985 tev = (*tevs) + ret; 2986 tp = &tev->point; 2987 if (ret == num_matched_functions) { 2988 pr_warning("Too many symbols are listed. Skip it.\n"); 2989 break; 2990 } 2991 ret++; 2992 2993 if (pp->offset > sym->end - sym->start) { 2994 pr_warning("Offset %ld is bigger than the size of %s\n", 2995 pp->offset, sym->name); 2996 ret = -ENOENT; 2997 goto err_out; 2998 } 2999 /* Add one probe point */ 3000 tp->address = map->unmap_ip(map, sym->start) + pp->offset; 3001 3002 /* Check the kprobe (not in module) is within .text */ 3003 if (!pev->uprobes && !pev->target && 3004 kprobe_warn_out_range(sym->name, tp->address)) { 3005 tp->symbol = NULL; /* Skip it */ 3006 skipped++; 3007 } else if (reloc_sym) { 3008 tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out); 3009 tp->offset = tp->address - reloc_sym->addr; 3010 } else { 3011 tp->symbol = strdup_or_goto(sym->name, nomem_out); 3012 tp->offset = pp->offset; 3013 } 3014 tp->realname = strdup_or_goto(sym->name, nomem_out); 3015 3016 tp->retprobe = pp->retprobe; 3017 if (pev->target) { 3018 if (pev->uprobes) { 3019 tev->point.module = strdup_or_goto(pev->target, 3020 nomem_out); 3021 } else { 3022 mod_name = find_module_name(pev->target); 3023 tev->point.module = 3024 strdup(mod_name ? mod_name : pev->target); 3025 free(mod_name); 3026 if (!tev->point.module) 3027 goto nomem_out; 3028 } 3029 } 3030 tev->uprobes = pev->uprobes; 3031 tev->nargs = pev->nargs; 3032 if (tev->nargs) { 3033 tev->args = zalloc(sizeof(struct probe_trace_arg) * 3034 tev->nargs); 3035 if (tev->args == NULL) 3036 goto nomem_out; 3037 } 3038 for (i = 0; i < tev->nargs; i++) { 3039 if (pev->args[i].name) 3040 tev->args[i].name = 3041 strdup_or_goto(pev->args[i].name, 3042 nomem_out); 3043 3044 tev->args[i].value = strdup_or_goto(pev->args[i].var, 3045 nomem_out); 3046 if (pev->args[i].type) 3047 tev->args[i].type = 3048 strdup_or_goto(pev->args[i].type, 3049 nomem_out); 3050 } 3051 arch__fix_tev_from_maps(pev, tev, map, sym); 3052 } 3053 if (ret == skipped) { 3054 ret = -ENOENT; 3055 goto err_out; 3056 } 3057 3058 out: 3059 map__put(map); 3060 free(syms); 3061 return ret; 3062 3063 nomem_out: 3064 ret = -ENOMEM; 3065 err_out: 3066 clear_probe_trace_events(*tevs, num_matched_functions); 3067 zfree(tevs); 3068 goto out; 3069 } 3070 3071 static int try_to_find_absolute_address(struct perf_probe_event *pev, 3072 struct probe_trace_event **tevs) 3073 { 3074 struct perf_probe_point *pp = &pev->point; 3075 struct probe_trace_event *tev; 3076 struct probe_trace_point *tp; 3077 int i, err; 3078 3079 if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2))) 3080 return -EINVAL; 3081 if (perf_probe_event_need_dwarf(pev)) 3082 return -EINVAL; 3083 3084 /* 3085 * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at 3086 * absolute address. 3087 * 3088 * Only one tev can be generated by this. 3089 */ 3090 *tevs = zalloc(sizeof(*tev)); 3091 if (!*tevs) 3092 return -ENOMEM; 3093 3094 tev = *tevs; 3095 tp = &tev->point; 3096 3097 /* 3098 * Don't use tp->offset, use address directly, because 3099 * in synthesize_probe_trace_command() address cannot be 3100 * zero. 3101 */ 3102 tp->address = pev->point.abs_address; 3103 tp->retprobe = pp->retprobe; 3104 tev->uprobes = pev->uprobes; 3105 3106 err = -ENOMEM; 3107 /* 3108 * Give it a '0x' leading symbol name. 3109 * In __add_probe_trace_events, a NULL symbol is interpreted as 3110 * invalid. 3111 */ 3112 if (asprintf(&tp->symbol, "0x%lx", tp->address) < 0) 3113 goto errout; 3114 3115 /* For kprobe, check range */ 3116 if ((!tev->uprobes) && 3117 (kprobe_warn_out_range(tev->point.symbol, 3118 tev->point.address))) { 3119 err = -EACCES; 3120 goto errout; 3121 } 3122 3123 if (asprintf(&tp->realname, "abs_%lx", tp->address) < 0) 3124 goto errout; 3125 3126 if (pev->target) { 3127 tp->module = strdup(pev->target); 3128 if (!tp->module) 3129 goto errout; 3130 } 3131 3132 if (tev->group) { 3133 tev->group = strdup(pev->group); 3134 if (!tev->group) 3135 goto errout; 3136 } 3137 3138 if (pev->event) { 3139 tev->event = strdup(pev->event); 3140 if (!tev->event) 3141 goto errout; 3142 } 3143 3144 tev->nargs = pev->nargs; 3145 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); 3146 if (!tev->args) 3147 goto errout; 3148 3149 for (i = 0; i < tev->nargs; i++) 3150 copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]); 3151 3152 return 1; 3153 3154 errout: 3155 clear_probe_trace_events(*tevs, 1); 3156 *tevs = NULL; 3157 return err; 3158 } 3159 3160 /* Concatinate two arrays */ 3161 static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b) 3162 { 3163 void *ret; 3164 3165 ret = malloc(sz_a + sz_b); 3166 if (ret) { 3167 memcpy(ret, a, sz_a); 3168 memcpy(ret + sz_a, b, sz_b); 3169 } 3170 return ret; 3171 } 3172 3173 static int 3174 concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs, 3175 struct probe_trace_event **tevs2, int ntevs2) 3176 { 3177 struct probe_trace_event *new_tevs; 3178 int ret = 0; 3179 3180 if (*ntevs == 0) { 3181 *tevs = *tevs2; 3182 *ntevs = ntevs2; 3183 *tevs2 = NULL; 3184 return 0; 3185 } 3186 3187 if (*ntevs + ntevs2 > probe_conf.max_probes) 3188 ret = -E2BIG; 3189 else { 3190 /* Concatinate the array of probe_trace_event */ 3191 new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs), 3192 *tevs2, ntevs2 * sizeof(**tevs2)); 3193 if (!new_tevs) 3194 ret = -ENOMEM; 3195 else { 3196 free(*tevs); 3197 *tevs = new_tevs; 3198 *ntevs += ntevs2; 3199 } 3200 } 3201 if (ret < 0) 3202 clear_probe_trace_events(*tevs2, ntevs2); 3203 zfree(tevs2); 3204 3205 return ret; 3206 } 3207 3208 /* 3209 * Try to find probe_trace_event from given probe caches. Return the number 3210 * of cached events found, if an error occurs return the error. 3211 */ 3212 static int find_cached_events(struct perf_probe_event *pev, 3213 struct probe_trace_event **tevs, 3214 const char *target) 3215 { 3216 struct probe_cache *cache; 3217 struct probe_cache_entry *entry; 3218 struct probe_trace_event *tmp_tevs = NULL; 3219 int ntevs = 0; 3220 int ret = 0; 3221 3222 cache = probe_cache__new(target, pev->nsi); 3223 /* Return 0 ("not found") if the target has no probe cache. */ 3224 if (!cache) 3225 return 0; 3226 3227 for_each_probe_cache_entry(entry, cache) { 3228 /* Skip the cache entry which has no name */ 3229 if (!entry->pev.event || !entry->pev.group) 3230 continue; 3231 if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) && 3232 strglobmatch(entry->pev.event, pev->event)) { 3233 ret = probe_cache_entry__get_event(entry, &tmp_tevs); 3234 if (ret > 0) 3235 ret = concat_probe_trace_events(tevs, &ntevs, 3236 &tmp_tevs, ret); 3237 if (ret < 0) 3238 break; 3239 } 3240 } 3241 probe_cache__delete(cache); 3242 if (ret < 0) { 3243 clear_probe_trace_events(*tevs, ntevs); 3244 zfree(tevs); 3245 } else { 3246 ret = ntevs; 3247 if (ntevs > 0 && target && target[0] == '/') 3248 pev->uprobes = true; 3249 } 3250 3251 return ret; 3252 } 3253 3254 /* Try to find probe_trace_event from all probe caches */ 3255 static int find_cached_events_all(struct perf_probe_event *pev, 3256 struct probe_trace_event **tevs) 3257 { 3258 struct probe_trace_event *tmp_tevs = NULL; 3259 struct strlist *bidlist; 3260 struct str_node *nd; 3261 char *pathname; 3262 int ntevs = 0; 3263 int ret; 3264 3265 /* Get the buildid list of all valid caches */ 3266 bidlist = build_id_cache__list_all(true); 3267 if (!bidlist) { 3268 ret = -errno; 3269 pr_debug("Failed to get buildids: %d\n", ret); 3270 return ret; 3271 } 3272 3273 ret = 0; 3274 strlist__for_each_entry(nd, bidlist) { 3275 pathname = build_id_cache__origname(nd->s); 3276 ret = find_cached_events(pev, &tmp_tevs, pathname); 3277 /* In the case of cnt == 0, we just skip it */ 3278 if (ret > 0) 3279 ret = concat_probe_trace_events(tevs, &ntevs, 3280 &tmp_tevs, ret); 3281 free(pathname); 3282 if (ret < 0) 3283 break; 3284 } 3285 strlist__delete(bidlist); 3286 3287 if (ret < 0) { 3288 clear_probe_trace_events(*tevs, ntevs); 3289 zfree(tevs); 3290 } else 3291 ret = ntevs; 3292 3293 return ret; 3294 } 3295 3296 static int find_probe_trace_events_from_cache(struct perf_probe_event *pev, 3297 struct probe_trace_event **tevs) 3298 { 3299 struct probe_cache *cache; 3300 struct probe_cache_entry *entry; 3301 struct probe_trace_event *tev; 3302 struct str_node *node; 3303 int ret, i; 3304 3305 if (pev->sdt) { 3306 /* For SDT/cached events, we use special search functions */ 3307 if (!pev->target) 3308 return find_cached_events_all(pev, tevs); 3309 else 3310 return find_cached_events(pev, tevs, pev->target); 3311 } 3312 cache = probe_cache__new(pev->target, pev->nsi); 3313 if (!cache) 3314 return 0; 3315 3316 entry = probe_cache__find(cache, pev); 3317 if (!entry) { 3318 /* SDT must be in the cache */ 3319 ret = pev->sdt ? -ENOENT : 0; 3320 goto out; 3321 } 3322 3323 ret = strlist__nr_entries(entry->tevlist); 3324 if (ret > probe_conf.max_probes) { 3325 pr_debug("Too many entries matched in the cache of %s\n", 3326 pev->target ? : "kernel"); 3327 ret = -E2BIG; 3328 goto out; 3329 } 3330 3331 *tevs = zalloc(ret * sizeof(*tev)); 3332 if (!*tevs) { 3333 ret = -ENOMEM; 3334 goto out; 3335 } 3336 3337 i = 0; 3338 strlist__for_each_entry(node, entry->tevlist) { 3339 tev = &(*tevs)[i++]; 3340 ret = parse_probe_trace_command(node->s, tev); 3341 if (ret < 0) 3342 goto out; 3343 /* Set the uprobes attribute as same as original */ 3344 tev->uprobes = pev->uprobes; 3345 } 3346 ret = i; 3347 3348 out: 3349 probe_cache__delete(cache); 3350 return ret; 3351 } 3352 3353 static int convert_to_probe_trace_events(struct perf_probe_event *pev, 3354 struct probe_trace_event **tevs) 3355 { 3356 int ret; 3357 3358 if (!pev->group && !pev->sdt) { 3359 /* Set group name if not given */ 3360 if (!pev->uprobes) { 3361 pev->group = strdup(PERFPROBE_GROUP); 3362 ret = pev->group ? 0 : -ENOMEM; 3363 } else 3364 ret = convert_exec_to_group(pev->target, &pev->group); 3365 if (ret != 0) { 3366 pr_warning("Failed to make a group name.\n"); 3367 return ret; 3368 } 3369 } 3370 3371 ret = try_to_find_absolute_address(pev, tevs); 3372 if (ret > 0) 3373 return ret; 3374 3375 /* At first, we need to lookup cache entry */ 3376 ret = find_probe_trace_events_from_cache(pev, tevs); 3377 if (ret > 0 || pev->sdt) /* SDT can be found only in the cache */ 3378 return ret == 0 ? -ENOENT : ret; /* Found in probe cache */ 3379 3380 /* Convert perf_probe_event with debuginfo */ 3381 ret = try_to_find_probe_trace_events(pev, tevs); 3382 if (ret != 0) 3383 return ret; /* Found in debuginfo or got an error */ 3384 3385 return find_probe_trace_events_from_map(pev, tevs); 3386 } 3387 3388 int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3389 { 3390 int i, ret; 3391 3392 /* Loop 1: convert all events */ 3393 for (i = 0; i < npevs; i++) { 3394 /* Init kprobe blacklist if needed */ 3395 if (!pevs[i].uprobes) 3396 kprobe_blacklist__init(); 3397 /* Convert with or without debuginfo */ 3398 ret = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs); 3399 if (ret < 0) 3400 return ret; 3401 pevs[i].ntevs = ret; 3402 } 3403 /* This just release blacklist only if allocated */ 3404 kprobe_blacklist__release(); 3405 3406 return 0; 3407 } 3408 3409 static int show_probe_trace_event(struct probe_trace_event *tev) 3410 { 3411 char *buf = synthesize_probe_trace_command(tev); 3412 3413 if (!buf) { 3414 pr_debug("Failed to synthesize probe trace event.\n"); 3415 return -EINVAL; 3416 } 3417 3418 /* Showing definition always go stdout */ 3419 printf("%s\n", buf); 3420 free(buf); 3421 3422 return 0; 3423 } 3424 3425 int show_probe_trace_events(struct perf_probe_event *pevs, int npevs) 3426 { 3427 struct strlist *namelist = strlist__new(NULL, NULL); 3428 struct probe_trace_event *tev; 3429 struct perf_probe_event *pev; 3430 int i, j, ret = 0; 3431 3432 if (!namelist) 3433 return -ENOMEM; 3434 3435 for (j = 0; j < npevs && !ret; j++) { 3436 pev = &pevs[j]; 3437 for (i = 0; i < pev->ntevs && !ret; i++) { 3438 tev = &pev->tevs[i]; 3439 /* Skip if the symbol is out of .text or blacklisted */ 3440 if (!tev->point.symbol && !pev->uprobes) 3441 continue; 3442 3443 /* Set new name for tev (and update namelist) */ 3444 ret = probe_trace_event__set_name(tev, pev, 3445 namelist, true); 3446 if (!ret) 3447 ret = show_probe_trace_event(tev); 3448 } 3449 } 3450 strlist__delete(namelist); 3451 3452 return ret; 3453 } 3454 3455 int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3456 { 3457 int i, ret = 0; 3458 3459 /* Loop 2: add all events */ 3460 for (i = 0; i < npevs; i++) { 3461 ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs, 3462 pevs[i].ntevs, 3463 probe_conf.force_add); 3464 if (ret < 0) 3465 break; 3466 } 3467 return ret; 3468 } 3469 3470 void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3471 { 3472 int i, j; 3473 struct perf_probe_event *pev; 3474 3475 /* Loop 3: cleanup and free trace events */ 3476 for (i = 0; i < npevs; i++) { 3477 pev = &pevs[i]; 3478 for (j = 0; j < pevs[i].ntevs; j++) 3479 clear_probe_trace_event(&pevs[i].tevs[j]); 3480 zfree(&pevs[i].tevs); 3481 pevs[i].ntevs = 0; 3482 nsinfo__zput(pev->nsi); 3483 clear_perf_probe_event(&pevs[i]); 3484 } 3485 } 3486 3487 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3488 { 3489 int ret; 3490 3491 ret = init_probe_symbol_maps(pevs->uprobes); 3492 if (ret < 0) 3493 return ret; 3494 3495 ret = convert_perf_probe_events(pevs, npevs); 3496 if (ret == 0) 3497 ret = apply_perf_probe_events(pevs, npevs); 3498 3499 cleanup_perf_probe_events(pevs, npevs); 3500 3501 exit_probe_symbol_maps(); 3502 return ret; 3503 } 3504 3505 int del_perf_probe_events(struct strfilter *filter) 3506 { 3507 int ret, ret2, ufd = -1, kfd = -1; 3508 char *str = strfilter__string(filter); 3509 3510 if (!str) 3511 return -EINVAL; 3512 3513 /* Get current event names */ 3514 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW); 3515 if (ret < 0) 3516 goto out; 3517 3518 ret = probe_file__del_events(kfd, filter); 3519 if (ret < 0 && ret != -ENOENT) 3520 goto error; 3521 3522 ret2 = probe_file__del_events(ufd, filter); 3523 if (ret2 < 0 && ret2 != -ENOENT) { 3524 ret = ret2; 3525 goto error; 3526 } 3527 ret = 0; 3528 3529 error: 3530 if (kfd >= 0) 3531 close(kfd); 3532 if (ufd >= 0) 3533 close(ufd); 3534 out: 3535 free(str); 3536 3537 return ret; 3538 } 3539 3540 int show_available_funcs(const char *target, struct nsinfo *nsi, 3541 struct strfilter *_filter, bool user) 3542 { 3543 struct rb_node *nd; 3544 struct map *map; 3545 int ret; 3546 3547 ret = init_probe_symbol_maps(user); 3548 if (ret < 0) 3549 return ret; 3550 3551 /* Get a symbol map */ 3552 map = get_target_map(target, nsi, user); 3553 if (!map) { 3554 pr_err("Failed to get a map for %s\n", (target) ? : "kernel"); 3555 return -EINVAL; 3556 } 3557 3558 ret = map__load(map); 3559 if (ret) { 3560 if (ret == -2) { 3561 char *str = strfilter__string(_filter); 3562 pr_err("Failed to find symbols matched to \"%s\"\n", 3563 str); 3564 free(str); 3565 } else 3566 pr_err("Failed to load symbols in %s\n", 3567 (target) ? : "kernel"); 3568 goto end; 3569 } 3570 if (!dso__sorted_by_name(map->dso)) 3571 dso__sort_by_name(map->dso); 3572 3573 /* Show all (filtered) symbols */ 3574 setup_pager(); 3575 3576 for (nd = rb_first_cached(&map->dso->symbol_names); nd; 3577 nd = rb_next(nd)) { 3578 struct symbol_name_rb_node *pos = rb_entry(nd, struct symbol_name_rb_node, rb_node); 3579 3580 if (strfilter__compare(_filter, pos->sym.name)) 3581 printf("%s\n", pos->sym.name); 3582 } 3583 end: 3584 map__put(map); 3585 exit_probe_symbol_maps(); 3586 3587 return ret; 3588 } 3589 3590 int copy_to_probe_trace_arg(struct probe_trace_arg *tvar, 3591 struct perf_probe_arg *pvar) 3592 { 3593 tvar->value = strdup(pvar->var); 3594 if (tvar->value == NULL) 3595 return -ENOMEM; 3596 if (pvar->type) { 3597 tvar->type = strdup(pvar->type); 3598 if (tvar->type == NULL) 3599 return -ENOMEM; 3600 } 3601 if (pvar->name) { 3602 tvar->name = strdup(pvar->name); 3603 if (tvar->name == NULL) 3604 return -ENOMEM; 3605 } else 3606 tvar->name = NULL; 3607 return 0; 3608 } 3609