1 /* 2 * probe-event.c : perf-probe definition to probe_events format converter 3 * 4 * Written by Masami Hiramatsu <mhiramat@redhat.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 * 20 */ 21 22 #include <inttypes.h> 23 #include <sys/utsname.h> 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <fcntl.h> 27 #include <errno.h> 28 #include <stdio.h> 29 #include <unistd.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <stdarg.h> 33 #include <limits.h> 34 #include <elf.h> 35 36 #include "util.h" 37 #include "event.h" 38 #include "strlist.h" 39 #include "strfilter.h" 40 #include "debug.h" 41 #include "cache.h" 42 #include "color.h" 43 #include "symbol.h" 44 #include "thread.h" 45 #include <api/fs/fs.h> 46 #include "trace-event.h" /* For __maybe_unused */ 47 #include "probe-event.h" 48 #include "probe-finder.h" 49 #include "probe-file.h" 50 #include "session.h" 51 #include "string2.h" 52 53 #include "sane_ctype.h" 54 55 #define PERFPROBE_GROUP "probe" 56 57 bool probe_event_dry_run; /* Dry run flag */ 58 struct probe_conf probe_conf; 59 60 #define semantic_error(msg ...) pr_err("Semantic error :" msg) 61 62 int e_snprintf(char *str, size_t size, const char *format, ...) 63 { 64 int ret; 65 va_list ap; 66 va_start(ap, format); 67 ret = vsnprintf(str, size, format, ap); 68 va_end(ap); 69 if (ret >= (int)size) 70 ret = -E2BIG; 71 return ret; 72 } 73 74 static struct machine *host_machine; 75 76 /* Initialize symbol maps and path of vmlinux/modules */ 77 int init_probe_symbol_maps(bool user_only) 78 { 79 int ret; 80 81 symbol_conf.sort_by_name = true; 82 symbol_conf.allow_aliases = true; 83 ret = symbol__init(NULL); 84 if (ret < 0) { 85 pr_debug("Failed to init symbol map.\n"); 86 goto out; 87 } 88 89 if (host_machine || user_only) /* already initialized */ 90 return 0; 91 92 if (symbol_conf.vmlinux_name) 93 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name); 94 95 host_machine = machine__new_host(); 96 if (!host_machine) { 97 pr_debug("machine__new_host() failed.\n"); 98 symbol__exit(); 99 ret = -1; 100 } 101 out: 102 if (ret < 0) 103 pr_warning("Failed to init vmlinux path.\n"); 104 return ret; 105 } 106 107 void exit_probe_symbol_maps(void) 108 { 109 machine__delete(host_machine); 110 host_machine = NULL; 111 symbol__exit(); 112 } 113 114 static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void) 115 { 116 /* kmap->ref_reloc_sym should be set if host_machine is initialized */ 117 struct kmap *kmap; 118 struct map *map = machine__kernel_map(host_machine); 119 120 if (map__load(map) < 0) 121 return NULL; 122 123 kmap = map__kmap(map); 124 if (!kmap) 125 return NULL; 126 return kmap->ref_reloc_sym; 127 } 128 129 static int kernel_get_symbol_address_by_name(const char *name, u64 *addr, 130 bool reloc, bool reladdr) 131 { 132 struct ref_reloc_sym *reloc_sym; 133 struct symbol *sym; 134 struct map *map; 135 136 /* ref_reloc_sym is just a label. Need a special fix*/ 137 reloc_sym = kernel_get_ref_reloc_sym(); 138 if (reloc_sym && strcmp(name, reloc_sym->name) == 0) 139 *addr = (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr; 140 else { 141 sym = machine__find_kernel_symbol_by_name(host_machine, name, &map); 142 if (!sym) 143 return -ENOENT; 144 *addr = map->unmap_ip(map, sym->start) - 145 ((reloc) ? 0 : map->reloc) - 146 ((reladdr) ? map->start : 0); 147 } 148 return 0; 149 } 150 151 static struct map *kernel_get_module_map(const char *module) 152 { 153 struct maps *maps = machine__kernel_maps(host_machine); 154 struct map *pos; 155 156 /* A file path -- this is an offline module */ 157 if (module && strchr(module, '/')) 158 return dso__new_map(module); 159 160 if (!module) 161 module = "kernel"; 162 163 for (pos = maps__first(maps); pos; pos = map__next(pos)) { 164 /* short_name is "[module]" */ 165 if (strncmp(pos->dso->short_name + 1, module, 166 pos->dso->short_name_len - 2) == 0 && 167 module[pos->dso->short_name_len - 2] == '\0') { 168 return map__get(pos); 169 } 170 } 171 return NULL; 172 } 173 174 struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) 175 { 176 /* Init maps of given executable or kernel */ 177 if (user) { 178 struct map *map; 179 180 map = dso__new_map(target); 181 if (map && map->dso) 182 map->dso->nsinfo = nsinfo__get(nsi); 183 return map; 184 } else { 185 return kernel_get_module_map(target); 186 } 187 } 188 189 static int convert_exec_to_group(const char *exec, char **result) 190 { 191 char *ptr1, *ptr2, *exec_copy; 192 char buf[64]; 193 int ret; 194 195 exec_copy = strdup(exec); 196 if (!exec_copy) 197 return -ENOMEM; 198 199 ptr1 = basename(exec_copy); 200 if (!ptr1) { 201 ret = -EINVAL; 202 goto out; 203 } 204 205 for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) { 206 if (!isalnum(*ptr2) && *ptr2 != '_') { 207 *ptr2 = '\0'; 208 break; 209 } 210 } 211 212 ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1); 213 if (ret < 0) 214 goto out; 215 216 *result = strdup(buf); 217 ret = *result ? 0 : -ENOMEM; 218 219 out: 220 free(exec_copy); 221 return ret; 222 } 223 224 static void clear_perf_probe_point(struct perf_probe_point *pp) 225 { 226 free(pp->file); 227 free(pp->function); 228 free(pp->lazy_line); 229 } 230 231 static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs) 232 { 233 int i; 234 235 for (i = 0; i < ntevs; i++) 236 clear_probe_trace_event(tevs + i); 237 } 238 239 static bool kprobe_blacklist__listed(unsigned long address); 240 static bool kprobe_warn_out_range(const char *symbol, unsigned long address) 241 { 242 u64 etext_addr = 0; 243 int ret; 244 245 /* Get the address of _etext for checking non-probable text symbol */ 246 ret = kernel_get_symbol_address_by_name("_etext", &etext_addr, 247 false, false); 248 249 if (ret == 0 && etext_addr < address) 250 pr_warning("%s is out of .text, skip it.\n", symbol); 251 else if (kprobe_blacklist__listed(address)) 252 pr_warning("%s is blacklisted function, skip it.\n", symbol); 253 else 254 return false; 255 256 return true; 257 } 258 259 /* 260 * @module can be module name of module file path. In case of path, 261 * inspect elf and find out what is actual module name. 262 * Caller has to free mod_name after using it. 263 */ 264 static char *find_module_name(const char *module) 265 { 266 int fd; 267 Elf *elf; 268 GElf_Ehdr ehdr; 269 GElf_Shdr shdr; 270 Elf_Data *data; 271 Elf_Scn *sec; 272 char *mod_name = NULL; 273 int name_offset; 274 275 fd = open(module, O_RDONLY); 276 if (fd < 0) 277 return NULL; 278 279 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); 280 if (elf == NULL) 281 goto elf_err; 282 283 if (gelf_getehdr(elf, &ehdr) == NULL) 284 goto ret_err; 285 286 sec = elf_section_by_name(elf, &ehdr, &shdr, 287 ".gnu.linkonce.this_module", NULL); 288 if (!sec) 289 goto ret_err; 290 291 data = elf_getdata(sec, NULL); 292 if (!data || !data->d_buf) 293 goto ret_err; 294 295 /* 296 * NOTE: 297 * '.gnu.linkonce.this_module' section of kernel module elf directly 298 * maps to 'struct module' from linux/module.h. This section contains 299 * actual module name which will be used by kernel after loading it. 300 * But, we cannot use 'struct module' here since linux/module.h is not 301 * exposed to user-space. Offset of 'name' has remained same from long 302 * time, so hardcoding it here. 303 */ 304 if (ehdr.e_ident[EI_CLASS] == ELFCLASS32) 305 name_offset = 12; 306 else /* expect ELFCLASS64 by default */ 307 name_offset = 24; 308 309 mod_name = strdup((char *)data->d_buf + name_offset); 310 311 ret_err: 312 elf_end(elf); 313 elf_err: 314 close(fd); 315 return mod_name; 316 } 317 318 #ifdef HAVE_DWARF_SUPPORT 319 320 static int kernel_get_module_dso(const char *module, struct dso **pdso) 321 { 322 struct dso *dso; 323 struct map *map; 324 const char *vmlinux_name; 325 int ret = 0; 326 327 if (module) { 328 char module_name[128]; 329 330 snprintf(module_name, sizeof(module_name), "[%s]", module); 331 map = map_groups__find_by_name(&host_machine->kmaps, module_name); 332 if (map) { 333 dso = map->dso; 334 goto found; 335 } 336 pr_debug("Failed to find module %s.\n", module); 337 return -ENOENT; 338 } 339 340 map = machine__kernel_map(host_machine); 341 dso = map->dso; 342 343 vmlinux_name = symbol_conf.vmlinux_name; 344 dso->load_errno = 0; 345 if (vmlinux_name) 346 ret = dso__load_vmlinux(dso, map, vmlinux_name, false); 347 else 348 ret = dso__load_vmlinux_path(dso, map); 349 found: 350 *pdso = dso; 351 return ret; 352 } 353 354 /* 355 * Some binaries like glibc have special symbols which are on the symbol 356 * table, but not in the debuginfo. If we can find the address of the 357 * symbol from map, we can translate the address back to the probe point. 358 */ 359 static int find_alternative_probe_point(struct debuginfo *dinfo, 360 struct perf_probe_point *pp, 361 struct perf_probe_point *result, 362 const char *target, struct nsinfo *nsi, 363 bool uprobes) 364 { 365 struct map *map = NULL; 366 struct symbol *sym; 367 u64 address = 0; 368 int ret = -ENOENT; 369 370 /* This can work only for function-name based one */ 371 if (!pp->function || pp->file) 372 return -ENOTSUP; 373 374 map = get_target_map(target, nsi, uprobes); 375 if (!map) 376 return -EINVAL; 377 378 /* Find the address of given function */ 379 map__for_each_symbol_by_name(map, pp->function, sym) { 380 if (uprobes) 381 address = sym->start; 382 else 383 address = map->unmap_ip(map, sym->start) - map->reloc; 384 break; 385 } 386 if (!address) { 387 ret = -ENOENT; 388 goto out; 389 } 390 pr_debug("Symbol %s address found : %" PRIx64 "\n", 391 pp->function, address); 392 393 ret = debuginfo__find_probe_point(dinfo, (unsigned long)address, 394 result); 395 if (ret <= 0) 396 ret = (!ret) ? -ENOENT : ret; 397 else { 398 result->offset += pp->offset; 399 result->line += pp->line; 400 result->retprobe = pp->retprobe; 401 ret = 0; 402 } 403 404 out: 405 map__put(map); 406 return ret; 407 408 } 409 410 static int get_alternative_probe_event(struct debuginfo *dinfo, 411 struct perf_probe_event *pev, 412 struct perf_probe_point *tmp) 413 { 414 int ret; 415 416 memcpy(tmp, &pev->point, sizeof(*tmp)); 417 memset(&pev->point, 0, sizeof(pev->point)); 418 ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target, 419 pev->nsi, pev->uprobes); 420 if (ret < 0) 421 memcpy(&pev->point, tmp, sizeof(*tmp)); 422 423 return ret; 424 } 425 426 static int get_alternative_line_range(struct debuginfo *dinfo, 427 struct line_range *lr, 428 const char *target, bool user) 429 { 430 struct perf_probe_point pp = { .function = lr->function, 431 .file = lr->file, 432 .line = lr->start }; 433 struct perf_probe_point result; 434 int ret, len = 0; 435 436 memset(&result, 0, sizeof(result)); 437 438 if (lr->end != INT_MAX) 439 len = lr->end - lr->start; 440 ret = find_alternative_probe_point(dinfo, &pp, &result, 441 target, NULL, user); 442 if (!ret) { 443 lr->function = result.function; 444 lr->file = result.file; 445 lr->start = result.line; 446 if (lr->end != INT_MAX) 447 lr->end = lr->start + len; 448 clear_perf_probe_point(&pp); 449 } 450 return ret; 451 } 452 453 /* Open new debuginfo of given module */ 454 static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi, 455 bool silent) 456 { 457 const char *path = module; 458 char reason[STRERR_BUFSIZE]; 459 struct debuginfo *ret = NULL; 460 struct dso *dso = NULL; 461 struct nscookie nsc; 462 int err; 463 464 if (!module || !strchr(module, '/')) { 465 err = kernel_get_module_dso(module, &dso); 466 if (err < 0) { 467 if (!dso || dso->load_errno == 0) { 468 if (!str_error_r(-err, reason, STRERR_BUFSIZE)) 469 strcpy(reason, "(unknown)"); 470 } else 471 dso__strerror_load(dso, reason, STRERR_BUFSIZE); 472 if (!silent) 473 pr_err("Failed to find the path for %s: %s\n", 474 module ?: "kernel", reason); 475 return NULL; 476 } 477 path = dso->long_name; 478 } 479 nsinfo__mountns_enter(nsi, &nsc); 480 ret = debuginfo__new(path); 481 if (!ret && !silent) { 482 pr_warning("The %s file has no debug information.\n", path); 483 if (!module || !strtailcmp(path, ".ko")) 484 pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, "); 485 else 486 pr_warning("Rebuild with -g, "); 487 pr_warning("or install an appropriate debuginfo package.\n"); 488 } 489 nsinfo__mountns_exit(&nsc); 490 return ret; 491 } 492 493 /* For caching the last debuginfo */ 494 static struct debuginfo *debuginfo_cache; 495 static char *debuginfo_cache_path; 496 497 static struct debuginfo *debuginfo_cache__open(const char *module, bool silent) 498 { 499 const char *path = module; 500 501 /* If the module is NULL, it should be the kernel. */ 502 if (!module) 503 path = "kernel"; 504 505 if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path)) 506 goto out; 507 508 /* Copy module path */ 509 free(debuginfo_cache_path); 510 debuginfo_cache_path = strdup(path); 511 if (!debuginfo_cache_path) { 512 debuginfo__delete(debuginfo_cache); 513 debuginfo_cache = NULL; 514 goto out; 515 } 516 517 debuginfo_cache = open_debuginfo(module, NULL, silent); 518 if (!debuginfo_cache) 519 zfree(&debuginfo_cache_path); 520 out: 521 return debuginfo_cache; 522 } 523 524 static void debuginfo_cache__exit(void) 525 { 526 debuginfo__delete(debuginfo_cache); 527 debuginfo_cache = NULL; 528 zfree(&debuginfo_cache_path); 529 } 530 531 532 static int get_text_start_address(const char *exec, unsigned long *address, 533 struct nsinfo *nsi) 534 { 535 Elf *elf; 536 GElf_Ehdr ehdr; 537 GElf_Shdr shdr; 538 int fd, ret = -ENOENT; 539 struct nscookie nsc; 540 541 nsinfo__mountns_enter(nsi, &nsc); 542 fd = open(exec, O_RDONLY); 543 nsinfo__mountns_exit(&nsc); 544 if (fd < 0) 545 return -errno; 546 547 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); 548 if (elf == NULL) { 549 ret = -EINVAL; 550 goto out_close; 551 } 552 553 if (gelf_getehdr(elf, &ehdr) == NULL) 554 goto out; 555 556 if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL)) 557 goto out; 558 559 *address = shdr.sh_addr - shdr.sh_offset; 560 ret = 0; 561 out: 562 elf_end(elf); 563 out_close: 564 close(fd); 565 566 return ret; 567 } 568 569 /* 570 * Convert trace point to probe point with debuginfo 571 */ 572 static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp, 573 struct perf_probe_point *pp, 574 bool is_kprobe) 575 { 576 struct debuginfo *dinfo = NULL; 577 unsigned long stext = 0; 578 u64 addr = tp->address; 579 int ret = -ENOENT; 580 581 /* convert the address to dwarf address */ 582 if (!is_kprobe) { 583 if (!addr) { 584 ret = -EINVAL; 585 goto error; 586 } 587 ret = get_text_start_address(tp->module, &stext, NULL); 588 if (ret < 0) 589 goto error; 590 addr += stext; 591 } else if (tp->symbol) { 592 /* If the module is given, this returns relative address */ 593 ret = kernel_get_symbol_address_by_name(tp->symbol, &addr, 594 false, !!tp->module); 595 if (ret != 0) 596 goto error; 597 addr += tp->offset; 598 } 599 600 pr_debug("try to find information at %" PRIx64 " in %s\n", addr, 601 tp->module ? : "kernel"); 602 603 dinfo = debuginfo_cache__open(tp->module, verbose <= 0); 604 if (dinfo) 605 ret = debuginfo__find_probe_point(dinfo, 606 (unsigned long)addr, pp); 607 else 608 ret = -ENOENT; 609 610 if (ret > 0) { 611 pp->retprobe = tp->retprobe; 612 return 0; 613 } 614 error: 615 pr_debug("Failed to find corresponding probes from debuginfo.\n"); 616 return ret ? : -ENOENT; 617 } 618 619 /* Adjust symbol name and address */ 620 static int post_process_probe_trace_point(struct probe_trace_point *tp, 621 struct map *map, unsigned long offs) 622 { 623 struct symbol *sym; 624 u64 addr = tp->address - offs; 625 626 sym = map__find_symbol(map, addr); 627 if (!sym) 628 return -ENOENT; 629 630 if (strcmp(sym->name, tp->symbol)) { 631 /* If we have no realname, use symbol for it */ 632 if (!tp->realname) 633 tp->realname = tp->symbol; 634 else 635 free(tp->symbol); 636 tp->symbol = strdup(sym->name); 637 if (!tp->symbol) 638 return -ENOMEM; 639 } 640 tp->offset = addr - sym->start; 641 tp->address -= offs; 642 643 return 0; 644 } 645 646 /* 647 * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions 648 * and generate new symbols with suffixes such as .constprop.N or .isra.N 649 * etc. Since those symbols are not recorded in DWARF, we have to find 650 * correct generated symbols from offline ELF binary. 651 * For online kernel or uprobes we don't need this because those are 652 * rebased on _text, or already a section relative address. 653 */ 654 static int 655 post_process_offline_probe_trace_events(struct probe_trace_event *tevs, 656 int ntevs, const char *pathname) 657 { 658 struct map *map; 659 unsigned long stext = 0; 660 int i, ret = 0; 661 662 /* Prepare a map for offline binary */ 663 map = dso__new_map(pathname); 664 if (!map || get_text_start_address(pathname, &stext, NULL) < 0) { 665 pr_warning("Failed to get ELF symbols for %s\n", pathname); 666 return -EINVAL; 667 } 668 669 for (i = 0; i < ntevs; i++) { 670 ret = post_process_probe_trace_point(&tevs[i].point, 671 map, stext); 672 if (ret < 0) 673 break; 674 } 675 map__put(map); 676 677 return ret; 678 } 679 680 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, 681 int ntevs, const char *exec, 682 struct nsinfo *nsi) 683 { 684 int i, ret = 0; 685 unsigned long stext = 0; 686 687 if (!exec) 688 return 0; 689 690 ret = get_text_start_address(exec, &stext, nsi); 691 if (ret < 0) 692 return ret; 693 694 for (i = 0; i < ntevs && ret >= 0; i++) { 695 /* point.address is the addres of point.symbol + point.offset */ 696 tevs[i].point.address -= stext; 697 tevs[i].point.module = strdup(exec); 698 if (!tevs[i].point.module) { 699 ret = -ENOMEM; 700 break; 701 } 702 tevs[i].uprobes = true; 703 } 704 705 return ret; 706 } 707 708 static int 709 post_process_module_probe_trace_events(struct probe_trace_event *tevs, 710 int ntevs, const char *module, 711 struct debuginfo *dinfo) 712 { 713 Dwarf_Addr text_offs = 0; 714 int i, ret = 0; 715 char *mod_name = NULL; 716 struct map *map; 717 718 if (!module) 719 return 0; 720 721 map = get_target_map(module, NULL, false); 722 if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) { 723 pr_warning("Failed to get ELF symbols for %s\n", module); 724 return -EINVAL; 725 } 726 727 mod_name = find_module_name(module); 728 for (i = 0; i < ntevs; i++) { 729 ret = post_process_probe_trace_point(&tevs[i].point, 730 map, (unsigned long)text_offs); 731 if (ret < 0) 732 break; 733 tevs[i].point.module = 734 strdup(mod_name ? mod_name : module); 735 if (!tevs[i].point.module) { 736 ret = -ENOMEM; 737 break; 738 } 739 } 740 741 free(mod_name); 742 map__put(map); 743 744 return ret; 745 } 746 747 static int 748 post_process_kernel_probe_trace_events(struct probe_trace_event *tevs, 749 int ntevs) 750 { 751 struct ref_reloc_sym *reloc_sym; 752 char *tmp; 753 int i, skipped = 0; 754 755 /* Skip post process if the target is an offline kernel */ 756 if (symbol_conf.ignore_vmlinux_buildid) 757 return post_process_offline_probe_trace_events(tevs, ntevs, 758 symbol_conf.vmlinux_name); 759 760 reloc_sym = kernel_get_ref_reloc_sym(); 761 if (!reloc_sym) { 762 pr_warning("Relocated base symbol is not found!\n"); 763 return -EINVAL; 764 } 765 766 for (i = 0; i < ntevs; i++) { 767 if (!tevs[i].point.address) 768 continue; 769 if (tevs[i].point.retprobe && !kretprobe_offset_is_supported()) 770 continue; 771 /* If we found a wrong one, mark it by NULL symbol */ 772 if (kprobe_warn_out_range(tevs[i].point.symbol, 773 tevs[i].point.address)) { 774 tmp = NULL; 775 skipped++; 776 } else { 777 tmp = strdup(reloc_sym->name); 778 if (!tmp) 779 return -ENOMEM; 780 } 781 /* If we have no realname, use symbol for it */ 782 if (!tevs[i].point.realname) 783 tevs[i].point.realname = tevs[i].point.symbol; 784 else 785 free(tevs[i].point.symbol); 786 tevs[i].point.symbol = tmp; 787 tevs[i].point.offset = tevs[i].point.address - 788 reloc_sym->unrelocated_addr; 789 } 790 return skipped; 791 } 792 793 void __weak 794 arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused, 795 int ntevs __maybe_unused) 796 { 797 } 798 799 /* Post processing the probe events */ 800 static int post_process_probe_trace_events(struct perf_probe_event *pev, 801 struct probe_trace_event *tevs, 802 int ntevs, const char *module, 803 bool uprobe, struct debuginfo *dinfo) 804 { 805 int ret; 806 807 if (uprobe) 808 ret = add_exec_to_probe_trace_events(tevs, ntevs, module, 809 pev->nsi); 810 else if (module) 811 /* Currently ref_reloc_sym based probe is not for drivers */ 812 ret = post_process_module_probe_trace_events(tevs, ntevs, 813 module, dinfo); 814 else 815 ret = post_process_kernel_probe_trace_events(tevs, ntevs); 816 817 if (ret >= 0) 818 arch__post_process_probe_trace_events(pev, ntevs); 819 820 return ret; 821 } 822 823 /* Try to find perf_probe_event with debuginfo */ 824 static int try_to_find_probe_trace_events(struct perf_probe_event *pev, 825 struct probe_trace_event **tevs) 826 { 827 bool need_dwarf = perf_probe_event_need_dwarf(pev); 828 struct perf_probe_point tmp; 829 struct debuginfo *dinfo; 830 int ntevs, ret = 0; 831 832 dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf); 833 if (!dinfo) { 834 if (need_dwarf) 835 return -ENOENT; 836 pr_debug("Could not open debuginfo. Try to use symbols.\n"); 837 return 0; 838 } 839 840 pr_debug("Try to find probe point from debuginfo.\n"); 841 /* Searching trace events corresponding to a probe event */ 842 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); 843 844 if (ntevs == 0) { /* Not found, retry with an alternative */ 845 ret = get_alternative_probe_event(dinfo, pev, &tmp); 846 if (!ret) { 847 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs); 848 /* 849 * Write back to the original probe_event for 850 * setting appropriate (user given) event name 851 */ 852 clear_perf_probe_point(&pev->point); 853 memcpy(&pev->point, &tmp, sizeof(tmp)); 854 } 855 } 856 857 if (ntevs > 0) { /* Succeeded to find trace events */ 858 pr_debug("Found %d probe_trace_events.\n", ntevs); 859 ret = post_process_probe_trace_events(pev, *tevs, ntevs, 860 pev->target, pev->uprobes, dinfo); 861 if (ret < 0 || ret == ntevs) { 862 pr_debug("Post processing failed or all events are skipped. (%d)\n", ret); 863 clear_probe_trace_events(*tevs, ntevs); 864 zfree(tevs); 865 ntevs = 0; 866 } 867 } 868 869 debuginfo__delete(dinfo); 870 871 if (ntevs == 0) { /* No error but failed to find probe point. */ 872 pr_warning("Probe point '%s' not found.\n", 873 synthesize_perf_probe_point(&pev->point)); 874 return -ENOENT; 875 } else if (ntevs < 0) { 876 /* Error path : ntevs < 0 */ 877 pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs); 878 if (ntevs == -EBADF) 879 pr_warning("Warning: No dwarf info found in the vmlinux - " 880 "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n"); 881 if (!need_dwarf) { 882 pr_debug("Trying to use symbols.\n"); 883 return 0; 884 } 885 } 886 return ntevs; 887 } 888 889 #define LINEBUF_SIZE 256 890 #define NR_ADDITIONAL_LINES 2 891 892 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num) 893 { 894 char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE]; 895 const char *color = show_num ? "" : PERF_COLOR_BLUE; 896 const char *prefix = NULL; 897 898 do { 899 if (fgets(buf, LINEBUF_SIZE, fp) == NULL) 900 goto error; 901 if (skip) 902 continue; 903 if (!prefix) { 904 prefix = show_num ? "%7d " : " "; 905 color_fprintf(stdout, color, prefix, l); 906 } 907 color_fprintf(stdout, color, "%s", buf); 908 909 } while (strchr(buf, '\n') == NULL); 910 911 return 1; 912 error: 913 if (ferror(fp)) { 914 pr_warning("File read error: %s\n", 915 str_error_r(errno, sbuf, sizeof(sbuf))); 916 return -1; 917 } 918 return 0; 919 } 920 921 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num) 922 { 923 int rv = __show_one_line(fp, l, skip, show_num); 924 if (rv == 0) { 925 pr_warning("Source file is shorter than expected.\n"); 926 rv = -1; 927 } 928 return rv; 929 } 930 931 #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true) 932 #define show_one_line(f,l) _show_one_line(f,l,false,false) 933 #define skip_one_line(f,l) _show_one_line(f,l,true,false) 934 #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false) 935 936 /* 937 * Show line-range always requires debuginfo to find source file and 938 * line number. 939 */ 940 static int __show_line_range(struct line_range *lr, const char *module, 941 bool user) 942 { 943 int l = 1; 944 struct int_node *ln; 945 struct debuginfo *dinfo; 946 FILE *fp; 947 int ret; 948 char *tmp; 949 char sbuf[STRERR_BUFSIZE]; 950 951 /* Search a line range */ 952 dinfo = open_debuginfo(module, NULL, false); 953 if (!dinfo) 954 return -ENOENT; 955 956 ret = debuginfo__find_line_range(dinfo, lr); 957 if (!ret) { /* Not found, retry with an alternative */ 958 ret = get_alternative_line_range(dinfo, lr, module, user); 959 if (!ret) 960 ret = debuginfo__find_line_range(dinfo, lr); 961 } 962 debuginfo__delete(dinfo); 963 if (ret == 0 || ret == -ENOENT) { 964 pr_warning("Specified source line is not found.\n"); 965 return -ENOENT; 966 } else if (ret < 0) { 967 pr_warning("Debuginfo analysis failed.\n"); 968 return ret; 969 } 970 971 /* Convert source file path */ 972 tmp = lr->path; 973 ret = get_real_path(tmp, lr->comp_dir, &lr->path); 974 975 /* Free old path when new path is assigned */ 976 if (tmp != lr->path) 977 free(tmp); 978 979 if (ret < 0) { 980 pr_warning("Failed to find source file path.\n"); 981 return ret; 982 } 983 984 setup_pager(); 985 986 if (lr->function) 987 fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path, 988 lr->start - lr->offset); 989 else 990 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start); 991 992 fp = fopen(lr->path, "r"); 993 if (fp == NULL) { 994 pr_warning("Failed to open %s: %s\n", lr->path, 995 str_error_r(errno, sbuf, sizeof(sbuf))); 996 return -errno; 997 } 998 /* Skip to starting line number */ 999 while (l < lr->start) { 1000 ret = skip_one_line(fp, l++); 1001 if (ret < 0) 1002 goto end; 1003 } 1004 1005 intlist__for_each_entry(ln, lr->line_list) { 1006 for (; ln->i > l; l++) { 1007 ret = show_one_line(fp, l - lr->offset); 1008 if (ret < 0) 1009 goto end; 1010 } 1011 ret = show_one_line_with_num(fp, l++ - lr->offset); 1012 if (ret < 0) 1013 goto end; 1014 } 1015 1016 if (lr->end == INT_MAX) 1017 lr->end = l + NR_ADDITIONAL_LINES; 1018 while (l <= lr->end) { 1019 ret = show_one_line_or_eof(fp, l++ - lr->offset); 1020 if (ret <= 0) 1021 break; 1022 } 1023 end: 1024 fclose(fp); 1025 return ret; 1026 } 1027 1028 int show_line_range(struct line_range *lr, const char *module, 1029 struct nsinfo *nsi, bool user) 1030 { 1031 int ret; 1032 struct nscookie nsc; 1033 1034 ret = init_probe_symbol_maps(user); 1035 if (ret < 0) 1036 return ret; 1037 nsinfo__mountns_enter(nsi, &nsc); 1038 ret = __show_line_range(lr, module, user); 1039 nsinfo__mountns_exit(&nsc); 1040 exit_probe_symbol_maps(); 1041 1042 return ret; 1043 } 1044 1045 static int show_available_vars_at(struct debuginfo *dinfo, 1046 struct perf_probe_event *pev, 1047 struct strfilter *_filter) 1048 { 1049 char *buf; 1050 int ret, i, nvars; 1051 struct str_node *node; 1052 struct variable_list *vls = NULL, *vl; 1053 struct perf_probe_point tmp; 1054 const char *var; 1055 1056 buf = synthesize_perf_probe_point(&pev->point); 1057 if (!buf) 1058 return -EINVAL; 1059 pr_debug("Searching variables at %s\n", buf); 1060 1061 ret = debuginfo__find_available_vars_at(dinfo, pev, &vls); 1062 if (!ret) { /* Not found, retry with an alternative */ 1063 ret = get_alternative_probe_event(dinfo, pev, &tmp); 1064 if (!ret) { 1065 ret = debuginfo__find_available_vars_at(dinfo, pev, 1066 &vls); 1067 /* Release the old probe_point */ 1068 clear_perf_probe_point(&tmp); 1069 } 1070 } 1071 if (ret <= 0) { 1072 if (ret == 0 || ret == -ENOENT) { 1073 pr_err("Failed to find the address of %s\n", buf); 1074 ret = -ENOENT; 1075 } else 1076 pr_warning("Debuginfo analysis failed.\n"); 1077 goto end; 1078 } 1079 1080 /* Some variables are found */ 1081 fprintf(stdout, "Available variables at %s\n", buf); 1082 for (i = 0; i < ret; i++) { 1083 vl = &vls[i]; 1084 /* 1085 * A probe point might be converted to 1086 * several trace points. 1087 */ 1088 fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol, 1089 vl->point.offset); 1090 zfree(&vl->point.symbol); 1091 nvars = 0; 1092 if (vl->vars) { 1093 strlist__for_each_entry(node, vl->vars) { 1094 var = strchr(node->s, '\t') + 1; 1095 if (strfilter__compare(_filter, var)) { 1096 fprintf(stdout, "\t\t%s\n", node->s); 1097 nvars++; 1098 } 1099 } 1100 strlist__delete(vl->vars); 1101 } 1102 if (nvars == 0) 1103 fprintf(stdout, "\t\t(No matched variables)\n"); 1104 } 1105 free(vls); 1106 end: 1107 free(buf); 1108 return ret; 1109 } 1110 1111 /* Show available variables on given probe point */ 1112 int show_available_vars(struct perf_probe_event *pevs, int npevs, 1113 struct strfilter *_filter) 1114 { 1115 int i, ret = 0; 1116 struct debuginfo *dinfo; 1117 1118 ret = init_probe_symbol_maps(pevs->uprobes); 1119 if (ret < 0) 1120 return ret; 1121 1122 dinfo = open_debuginfo(pevs->target, pevs->nsi, false); 1123 if (!dinfo) { 1124 ret = -ENOENT; 1125 goto out; 1126 } 1127 1128 setup_pager(); 1129 1130 for (i = 0; i < npevs && ret >= 0; i++) 1131 ret = show_available_vars_at(dinfo, &pevs[i], _filter); 1132 1133 debuginfo__delete(dinfo); 1134 out: 1135 exit_probe_symbol_maps(); 1136 return ret; 1137 } 1138 1139 #else /* !HAVE_DWARF_SUPPORT */ 1140 1141 static void debuginfo_cache__exit(void) 1142 { 1143 } 1144 1145 static int 1146 find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused, 1147 struct perf_probe_point *pp __maybe_unused, 1148 bool is_kprobe __maybe_unused) 1149 { 1150 return -ENOSYS; 1151 } 1152 1153 static int try_to_find_probe_trace_events(struct perf_probe_event *pev, 1154 struct probe_trace_event **tevs __maybe_unused) 1155 { 1156 if (perf_probe_event_need_dwarf(pev)) { 1157 pr_warning("Debuginfo-analysis is not supported.\n"); 1158 return -ENOSYS; 1159 } 1160 1161 return 0; 1162 } 1163 1164 int show_line_range(struct line_range *lr __maybe_unused, 1165 const char *module __maybe_unused, 1166 struct nsinfo *nsi __maybe_unused, 1167 bool user __maybe_unused) 1168 { 1169 pr_warning("Debuginfo-analysis is not supported.\n"); 1170 return -ENOSYS; 1171 } 1172 1173 int show_available_vars(struct perf_probe_event *pevs __maybe_unused, 1174 int npevs __maybe_unused, 1175 struct strfilter *filter __maybe_unused) 1176 { 1177 pr_warning("Debuginfo-analysis is not supported.\n"); 1178 return -ENOSYS; 1179 } 1180 #endif 1181 1182 void line_range__clear(struct line_range *lr) 1183 { 1184 free(lr->function); 1185 free(lr->file); 1186 free(lr->path); 1187 free(lr->comp_dir); 1188 intlist__delete(lr->line_list); 1189 memset(lr, 0, sizeof(*lr)); 1190 } 1191 1192 int line_range__init(struct line_range *lr) 1193 { 1194 memset(lr, 0, sizeof(*lr)); 1195 lr->line_list = intlist__new(NULL); 1196 if (!lr->line_list) 1197 return -ENOMEM; 1198 else 1199 return 0; 1200 } 1201 1202 static int parse_line_num(char **ptr, int *val, const char *what) 1203 { 1204 const char *start = *ptr; 1205 1206 errno = 0; 1207 *val = strtol(*ptr, ptr, 0); 1208 if (errno || *ptr == start) { 1209 semantic_error("'%s' is not a valid number.\n", what); 1210 return -EINVAL; 1211 } 1212 return 0; 1213 } 1214 1215 /* Check the name is good for event, group or function */ 1216 static bool is_c_func_name(const char *name) 1217 { 1218 if (!isalpha(*name) && *name != '_') 1219 return false; 1220 while (*++name != '\0') { 1221 if (!isalpha(*name) && !isdigit(*name) && *name != '_') 1222 return false; 1223 } 1224 return true; 1225 } 1226 1227 /* 1228 * Stuff 'lr' according to the line range described by 'arg'. 1229 * The line range syntax is described by: 1230 * 1231 * SRC[:SLN[+NUM|-ELN]] 1232 * FNC[@SRC][:SLN[+NUM|-ELN]] 1233 */ 1234 int parse_line_range_desc(const char *arg, struct line_range *lr) 1235 { 1236 char *range, *file, *name = strdup(arg); 1237 int err; 1238 1239 if (!name) 1240 return -ENOMEM; 1241 1242 lr->start = 0; 1243 lr->end = INT_MAX; 1244 1245 range = strchr(name, ':'); 1246 if (range) { 1247 *range++ = '\0'; 1248 1249 err = parse_line_num(&range, &lr->start, "start line"); 1250 if (err) 1251 goto err; 1252 1253 if (*range == '+' || *range == '-') { 1254 const char c = *range++; 1255 1256 err = parse_line_num(&range, &lr->end, "end line"); 1257 if (err) 1258 goto err; 1259 1260 if (c == '+') { 1261 lr->end += lr->start; 1262 /* 1263 * Adjust the number of lines here. 1264 * If the number of lines == 1, the 1265 * the end of line should be equal to 1266 * the start of line. 1267 */ 1268 lr->end--; 1269 } 1270 } 1271 1272 pr_debug("Line range is %d to %d\n", lr->start, lr->end); 1273 1274 err = -EINVAL; 1275 if (lr->start > lr->end) { 1276 semantic_error("Start line must be smaller" 1277 " than end line.\n"); 1278 goto err; 1279 } 1280 if (*range != '\0') { 1281 semantic_error("Tailing with invalid str '%s'.\n", range); 1282 goto err; 1283 } 1284 } 1285 1286 file = strchr(name, '@'); 1287 if (file) { 1288 *file = '\0'; 1289 lr->file = strdup(++file); 1290 if (lr->file == NULL) { 1291 err = -ENOMEM; 1292 goto err; 1293 } 1294 lr->function = name; 1295 } else if (strchr(name, '/') || strchr(name, '.')) 1296 lr->file = name; 1297 else if (is_c_func_name(name))/* We reuse it for checking funcname */ 1298 lr->function = name; 1299 else { /* Invalid name */ 1300 semantic_error("'%s' is not a valid function name.\n", name); 1301 err = -EINVAL; 1302 goto err; 1303 } 1304 1305 return 0; 1306 err: 1307 free(name); 1308 return err; 1309 } 1310 1311 static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) 1312 { 1313 char *ptr; 1314 1315 ptr = strpbrk_esc(*arg, ":"); 1316 if (ptr) { 1317 *ptr = '\0'; 1318 if (!pev->sdt && !is_c_func_name(*arg)) 1319 goto ng_name; 1320 pev->group = strdup_esc(*arg); 1321 if (!pev->group) 1322 return -ENOMEM; 1323 *arg = ptr + 1; 1324 } else 1325 pev->group = NULL; 1326 1327 pev->event = strdup_esc(*arg); 1328 if (pev->event == NULL) 1329 return -ENOMEM; 1330 1331 if (!pev->sdt && !is_c_func_name(pev->event)) { 1332 zfree(&pev->event); 1333 ng_name: 1334 zfree(&pev->group); 1335 semantic_error("%s is bad for event name -it must " 1336 "follow C symbol-naming rule.\n", *arg); 1337 return -EINVAL; 1338 } 1339 return 0; 1340 } 1341 1342 /* Parse probepoint definition. */ 1343 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev) 1344 { 1345 struct perf_probe_point *pp = &pev->point; 1346 char *ptr, *tmp; 1347 char c, nc = 0; 1348 bool file_spec = false; 1349 int ret; 1350 1351 /* 1352 * <Syntax> 1353 * perf probe [GRP:][EVENT=]SRC[:LN|;PTN] 1354 * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT] 1355 * perf probe %[GRP:]SDT_EVENT 1356 */ 1357 if (!arg) 1358 return -EINVAL; 1359 1360 if (is_sdt_event(arg)) { 1361 pev->sdt = true; 1362 if (arg[0] == '%') 1363 arg++; 1364 } 1365 1366 ptr = strpbrk_esc(arg, ";=@+%"); 1367 if (pev->sdt) { 1368 if (ptr) { 1369 if (*ptr != '@') { 1370 semantic_error("%s must be an SDT name.\n", 1371 arg); 1372 return -EINVAL; 1373 } 1374 /* This must be a target file name or build id */ 1375 tmp = build_id_cache__complement(ptr + 1); 1376 if (tmp) { 1377 pev->target = build_id_cache__origname(tmp); 1378 free(tmp); 1379 } else 1380 pev->target = strdup_esc(ptr + 1); 1381 if (!pev->target) 1382 return -ENOMEM; 1383 *ptr = '\0'; 1384 } 1385 ret = parse_perf_probe_event_name(&arg, pev); 1386 if (ret == 0) { 1387 if (asprintf(&pev->point.function, "%%%s", pev->event) < 0) 1388 ret = -errno; 1389 } 1390 return ret; 1391 } 1392 1393 if (ptr && *ptr == '=') { /* Event name */ 1394 *ptr = '\0'; 1395 tmp = ptr + 1; 1396 ret = parse_perf_probe_event_name(&arg, pev); 1397 if (ret < 0) 1398 return ret; 1399 1400 arg = tmp; 1401 } 1402 1403 /* 1404 * Check arg is function or file name and copy it. 1405 * 1406 * We consider arg to be a file spec if and only if it satisfies 1407 * all of the below criteria:: 1408 * - it does not include any of "+@%", 1409 * - it includes one of ":;", and 1410 * - it has a period '.' in the name. 1411 * 1412 * Otherwise, we consider arg to be a function specification. 1413 */ 1414 if (!strpbrk_esc(arg, "+@%")) { 1415 ptr = strpbrk_esc(arg, ";:"); 1416 /* This is a file spec if it includes a '.' before ; or : */ 1417 if (ptr && memchr(arg, '.', ptr - arg)) 1418 file_spec = true; 1419 } 1420 1421 ptr = strpbrk_esc(arg, ";:+@%"); 1422 if (ptr) { 1423 nc = *ptr; 1424 *ptr++ = '\0'; 1425 } 1426 1427 if (arg[0] == '\0') 1428 tmp = NULL; 1429 else { 1430 tmp = strdup_esc(arg); 1431 if (tmp == NULL) 1432 return -ENOMEM; 1433 } 1434 1435 if (file_spec) 1436 pp->file = tmp; 1437 else { 1438 pp->function = tmp; 1439 1440 /* 1441 * Keep pp->function even if this is absolute address, 1442 * so it can mark whether abs_address is valid. 1443 * Which make 'perf probe lib.bin 0x0' possible. 1444 * 1445 * Note that checking length of tmp is not needed 1446 * because when we access tmp[1] we know tmp[0] is '0', 1447 * so tmp[1] should always valid (but could be '\0'). 1448 */ 1449 if (tmp && !strncmp(tmp, "0x", 2)) { 1450 pp->abs_address = strtoul(pp->function, &tmp, 0); 1451 if (*tmp != '\0') { 1452 semantic_error("Invalid absolute address.\n"); 1453 return -EINVAL; 1454 } 1455 } 1456 } 1457 1458 /* Parse other options */ 1459 while (ptr) { 1460 arg = ptr; 1461 c = nc; 1462 if (c == ';') { /* Lazy pattern must be the last part */ 1463 pp->lazy_line = strdup(arg); /* let leave escapes */ 1464 if (pp->lazy_line == NULL) 1465 return -ENOMEM; 1466 break; 1467 } 1468 ptr = strpbrk_esc(arg, ";:+@%"); 1469 if (ptr) { 1470 nc = *ptr; 1471 *ptr++ = '\0'; 1472 } 1473 switch (c) { 1474 case ':': /* Line number */ 1475 pp->line = strtoul(arg, &tmp, 0); 1476 if (*tmp != '\0') { 1477 semantic_error("There is non-digit char" 1478 " in line number.\n"); 1479 return -EINVAL; 1480 } 1481 break; 1482 case '+': /* Byte offset from a symbol */ 1483 pp->offset = strtoul(arg, &tmp, 0); 1484 if (*tmp != '\0') { 1485 semantic_error("There is non-digit character" 1486 " in offset.\n"); 1487 return -EINVAL; 1488 } 1489 break; 1490 case '@': /* File name */ 1491 if (pp->file) { 1492 semantic_error("SRC@SRC is not allowed.\n"); 1493 return -EINVAL; 1494 } 1495 pp->file = strdup_esc(arg); 1496 if (pp->file == NULL) 1497 return -ENOMEM; 1498 break; 1499 case '%': /* Probe places */ 1500 if (strcmp(arg, "return") == 0) { 1501 pp->retprobe = 1; 1502 } else { /* Others not supported yet */ 1503 semantic_error("%%%s is not supported.\n", arg); 1504 return -ENOTSUP; 1505 } 1506 break; 1507 default: /* Buggy case */ 1508 pr_err("This program has a bug at %s:%d.\n", 1509 __FILE__, __LINE__); 1510 return -ENOTSUP; 1511 break; 1512 } 1513 } 1514 1515 /* Exclusion check */ 1516 if (pp->lazy_line && pp->line) { 1517 semantic_error("Lazy pattern can't be used with" 1518 " line number.\n"); 1519 return -EINVAL; 1520 } 1521 1522 if (pp->lazy_line && pp->offset) { 1523 semantic_error("Lazy pattern can't be used with offset.\n"); 1524 return -EINVAL; 1525 } 1526 1527 if (pp->line && pp->offset) { 1528 semantic_error("Offset can't be used with line number.\n"); 1529 return -EINVAL; 1530 } 1531 1532 if (!pp->line && !pp->lazy_line && pp->file && !pp->function) { 1533 semantic_error("File always requires line number or " 1534 "lazy pattern.\n"); 1535 return -EINVAL; 1536 } 1537 1538 if (pp->offset && !pp->function) { 1539 semantic_error("Offset requires an entry function.\n"); 1540 return -EINVAL; 1541 } 1542 1543 if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) { 1544 semantic_error("Offset/Line/Lazy pattern can't be used with " 1545 "return probe.\n"); 1546 return -EINVAL; 1547 } 1548 1549 pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n", 1550 pp->function, pp->file, pp->line, pp->offset, pp->retprobe, 1551 pp->lazy_line); 1552 return 0; 1553 } 1554 1555 /* Parse perf-probe event argument */ 1556 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg) 1557 { 1558 char *tmp, *goodname; 1559 struct perf_probe_arg_field **fieldp; 1560 1561 pr_debug("parsing arg: %s into ", str); 1562 1563 tmp = strchr(str, '='); 1564 if (tmp) { 1565 arg->name = strndup(str, tmp - str); 1566 if (arg->name == NULL) 1567 return -ENOMEM; 1568 pr_debug("name:%s ", arg->name); 1569 str = tmp + 1; 1570 } 1571 1572 tmp = strchr(str, ':'); 1573 if (tmp) { /* Type setting */ 1574 *tmp = '\0'; 1575 arg->type = strdup(tmp + 1); 1576 if (arg->type == NULL) 1577 return -ENOMEM; 1578 pr_debug("type:%s ", arg->type); 1579 } 1580 1581 tmp = strpbrk(str, "-.["); 1582 if (!is_c_varname(str) || !tmp) { 1583 /* A variable, register, symbol or special value */ 1584 arg->var = strdup(str); 1585 if (arg->var == NULL) 1586 return -ENOMEM; 1587 pr_debug("%s\n", arg->var); 1588 return 0; 1589 } 1590 1591 /* Structure fields or array element */ 1592 arg->var = strndup(str, tmp - str); 1593 if (arg->var == NULL) 1594 return -ENOMEM; 1595 goodname = arg->var; 1596 pr_debug("%s, ", arg->var); 1597 fieldp = &arg->field; 1598 1599 do { 1600 *fieldp = zalloc(sizeof(struct perf_probe_arg_field)); 1601 if (*fieldp == NULL) 1602 return -ENOMEM; 1603 if (*tmp == '[') { /* Array */ 1604 str = tmp; 1605 (*fieldp)->index = strtol(str + 1, &tmp, 0); 1606 (*fieldp)->ref = true; 1607 if (*tmp != ']' || tmp == str + 1) { 1608 semantic_error("Array index must be a" 1609 " number.\n"); 1610 return -EINVAL; 1611 } 1612 tmp++; 1613 if (*tmp == '\0') 1614 tmp = NULL; 1615 } else { /* Structure */ 1616 if (*tmp == '.') { 1617 str = tmp + 1; 1618 (*fieldp)->ref = false; 1619 } else if (tmp[1] == '>') { 1620 str = tmp + 2; 1621 (*fieldp)->ref = true; 1622 } else { 1623 semantic_error("Argument parse error: %s\n", 1624 str); 1625 return -EINVAL; 1626 } 1627 tmp = strpbrk(str, "-.["); 1628 } 1629 if (tmp) { 1630 (*fieldp)->name = strndup(str, tmp - str); 1631 if ((*fieldp)->name == NULL) 1632 return -ENOMEM; 1633 if (*str != '[') 1634 goodname = (*fieldp)->name; 1635 pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref); 1636 fieldp = &(*fieldp)->next; 1637 } 1638 } while (tmp); 1639 (*fieldp)->name = strdup(str); 1640 if ((*fieldp)->name == NULL) 1641 return -ENOMEM; 1642 if (*str != '[') 1643 goodname = (*fieldp)->name; 1644 pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref); 1645 1646 /* If no name is specified, set the last field name (not array index)*/ 1647 if (!arg->name) { 1648 arg->name = strdup(goodname); 1649 if (arg->name == NULL) 1650 return -ENOMEM; 1651 } 1652 return 0; 1653 } 1654 1655 /* Parse perf-probe event command */ 1656 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev) 1657 { 1658 char **argv; 1659 int argc, i, ret = 0; 1660 1661 argv = argv_split(cmd, &argc); 1662 if (!argv) { 1663 pr_debug("Failed to split arguments.\n"); 1664 return -ENOMEM; 1665 } 1666 if (argc - 1 > MAX_PROBE_ARGS) { 1667 semantic_error("Too many probe arguments (%d).\n", argc - 1); 1668 ret = -ERANGE; 1669 goto out; 1670 } 1671 /* Parse probe point */ 1672 ret = parse_perf_probe_point(argv[0], pev); 1673 if (ret < 0) 1674 goto out; 1675 1676 /* Copy arguments and ensure return probe has no C argument */ 1677 pev->nargs = argc - 1; 1678 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); 1679 if (pev->args == NULL) { 1680 ret = -ENOMEM; 1681 goto out; 1682 } 1683 for (i = 0; i < pev->nargs && ret >= 0; i++) { 1684 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]); 1685 if (ret >= 0 && 1686 is_c_varname(pev->args[i].var) && pev->point.retprobe) { 1687 semantic_error("You can't specify local variable for" 1688 " kretprobe.\n"); 1689 ret = -EINVAL; 1690 } 1691 } 1692 out: 1693 argv_free(argv); 1694 1695 return ret; 1696 } 1697 1698 /* Returns true if *any* ARG is either C variable, $params or $vars. */ 1699 bool perf_probe_with_var(struct perf_probe_event *pev) 1700 { 1701 int i = 0; 1702 1703 for (i = 0; i < pev->nargs; i++) 1704 if (is_c_varname(pev->args[i].var) || 1705 !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) || 1706 !strcmp(pev->args[i].var, PROBE_ARG_VARS)) 1707 return true; 1708 return false; 1709 } 1710 1711 /* Return true if this perf_probe_event requires debuginfo */ 1712 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev) 1713 { 1714 if (pev->point.file || pev->point.line || pev->point.lazy_line) 1715 return true; 1716 1717 if (perf_probe_with_var(pev)) 1718 return true; 1719 1720 return false; 1721 } 1722 1723 /* Parse probe_events event into struct probe_point */ 1724 int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev) 1725 { 1726 struct probe_trace_point *tp = &tev->point; 1727 char pr; 1728 char *p; 1729 char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str; 1730 int ret, i, argc; 1731 char **argv; 1732 1733 pr_debug("Parsing probe_events: %s\n", cmd); 1734 argv = argv_split(cmd, &argc); 1735 if (!argv) { 1736 pr_debug("Failed to split arguments.\n"); 1737 return -ENOMEM; 1738 } 1739 if (argc < 2) { 1740 semantic_error("Too few probe arguments.\n"); 1741 ret = -ERANGE; 1742 goto out; 1743 } 1744 1745 /* Scan event and group name. */ 1746 argv0_str = strdup(argv[0]); 1747 if (argv0_str == NULL) { 1748 ret = -ENOMEM; 1749 goto out; 1750 } 1751 fmt1_str = strtok_r(argv0_str, ":", &fmt); 1752 fmt2_str = strtok_r(NULL, "/", &fmt); 1753 fmt3_str = strtok_r(NULL, " \t", &fmt); 1754 if (fmt1_str == NULL || strlen(fmt1_str) != 1 || fmt2_str == NULL 1755 || fmt3_str == NULL) { 1756 semantic_error("Failed to parse event name: %s\n", argv[0]); 1757 ret = -EINVAL; 1758 goto out; 1759 } 1760 pr = fmt1_str[0]; 1761 tev->group = strdup(fmt2_str); 1762 tev->event = strdup(fmt3_str); 1763 if (tev->group == NULL || tev->event == NULL) { 1764 ret = -ENOMEM; 1765 goto out; 1766 } 1767 pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr); 1768 1769 tp->retprobe = (pr == 'r'); 1770 1771 /* Scan module name(if there), function name and offset */ 1772 p = strchr(argv[1], ':'); 1773 if (p) { 1774 tp->module = strndup(argv[1], p - argv[1]); 1775 if (!tp->module) { 1776 ret = -ENOMEM; 1777 goto out; 1778 } 1779 tev->uprobes = (tp->module[0] == '/'); 1780 p++; 1781 } else 1782 p = argv[1]; 1783 fmt1_str = strtok_r(p, "+", &fmt); 1784 /* only the address started with 0x */ 1785 if (fmt1_str[0] == '0') { 1786 /* 1787 * Fix a special case: 1788 * if address == 0, kernel reports something like: 1789 * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax 1790 * Newer kernel may fix that, but we want to 1791 * support old kernel also. 1792 */ 1793 if (strcmp(fmt1_str, "0x") == 0) { 1794 if (!argv[2] || strcmp(argv[2], "(null)")) { 1795 ret = -EINVAL; 1796 goto out; 1797 } 1798 tp->address = 0; 1799 1800 free(argv[2]); 1801 for (i = 2; argv[i + 1] != NULL; i++) 1802 argv[i] = argv[i + 1]; 1803 1804 argv[i] = NULL; 1805 argc -= 1; 1806 } else 1807 tp->address = strtoul(fmt1_str, NULL, 0); 1808 } else { 1809 /* Only the symbol-based probe has offset */ 1810 tp->symbol = strdup(fmt1_str); 1811 if (tp->symbol == NULL) { 1812 ret = -ENOMEM; 1813 goto out; 1814 } 1815 fmt2_str = strtok_r(NULL, "", &fmt); 1816 if (fmt2_str == NULL) 1817 tp->offset = 0; 1818 else 1819 tp->offset = strtoul(fmt2_str, NULL, 10); 1820 } 1821 1822 tev->nargs = argc - 2; 1823 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); 1824 if (tev->args == NULL) { 1825 ret = -ENOMEM; 1826 goto out; 1827 } 1828 for (i = 0; i < tev->nargs; i++) { 1829 p = strchr(argv[i + 2], '='); 1830 if (p) /* We don't need which register is assigned. */ 1831 *p++ = '\0'; 1832 else 1833 p = argv[i + 2]; 1834 tev->args[i].name = strdup(argv[i + 2]); 1835 /* TODO: parse regs and offset */ 1836 tev->args[i].value = strdup(p); 1837 if (tev->args[i].name == NULL || tev->args[i].value == NULL) { 1838 ret = -ENOMEM; 1839 goto out; 1840 } 1841 } 1842 ret = 0; 1843 out: 1844 free(argv0_str); 1845 argv_free(argv); 1846 return ret; 1847 } 1848 1849 /* Compose only probe arg */ 1850 char *synthesize_perf_probe_arg(struct perf_probe_arg *pa) 1851 { 1852 struct perf_probe_arg_field *field = pa->field; 1853 struct strbuf buf; 1854 char *ret = NULL; 1855 int err; 1856 1857 if (strbuf_init(&buf, 64) < 0) 1858 return NULL; 1859 1860 if (pa->name && pa->var) 1861 err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var); 1862 else 1863 err = strbuf_addstr(&buf, pa->name ?: pa->var); 1864 if (err) 1865 goto out; 1866 1867 while (field) { 1868 if (field->name[0] == '[') 1869 err = strbuf_addstr(&buf, field->name); 1870 else 1871 err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".", 1872 field->name); 1873 field = field->next; 1874 if (err) 1875 goto out; 1876 } 1877 1878 if (pa->type) 1879 if (strbuf_addf(&buf, ":%s", pa->type) < 0) 1880 goto out; 1881 1882 ret = strbuf_detach(&buf, NULL); 1883 out: 1884 strbuf_release(&buf); 1885 return ret; 1886 } 1887 1888 /* Compose only probe point (not argument) */ 1889 char *synthesize_perf_probe_point(struct perf_probe_point *pp) 1890 { 1891 struct strbuf buf; 1892 char *tmp, *ret = NULL; 1893 int len, err = 0; 1894 1895 if (strbuf_init(&buf, 64) < 0) 1896 return NULL; 1897 1898 if (pp->function) { 1899 if (strbuf_addstr(&buf, pp->function) < 0) 1900 goto out; 1901 if (pp->offset) 1902 err = strbuf_addf(&buf, "+%lu", pp->offset); 1903 else if (pp->line) 1904 err = strbuf_addf(&buf, ":%d", pp->line); 1905 else if (pp->retprobe) 1906 err = strbuf_addstr(&buf, "%return"); 1907 if (err) 1908 goto out; 1909 } 1910 if (pp->file) { 1911 tmp = pp->file; 1912 len = strlen(tmp); 1913 if (len > 30) { 1914 tmp = strchr(pp->file + len - 30, '/'); 1915 tmp = tmp ? tmp + 1 : pp->file + len - 30; 1916 } 1917 err = strbuf_addf(&buf, "@%s", tmp); 1918 if (!err && !pp->function && pp->line) 1919 err = strbuf_addf(&buf, ":%d", pp->line); 1920 } 1921 if (!err) 1922 ret = strbuf_detach(&buf, NULL); 1923 out: 1924 strbuf_release(&buf); 1925 return ret; 1926 } 1927 1928 char *synthesize_perf_probe_command(struct perf_probe_event *pev) 1929 { 1930 struct strbuf buf; 1931 char *tmp, *ret = NULL; 1932 int i; 1933 1934 if (strbuf_init(&buf, 64)) 1935 return NULL; 1936 if (pev->event) 1937 if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP, 1938 pev->event) < 0) 1939 goto out; 1940 1941 tmp = synthesize_perf_probe_point(&pev->point); 1942 if (!tmp || strbuf_addstr(&buf, tmp) < 0) 1943 goto out; 1944 free(tmp); 1945 1946 for (i = 0; i < pev->nargs; i++) { 1947 tmp = synthesize_perf_probe_arg(pev->args + i); 1948 if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0) 1949 goto out; 1950 free(tmp); 1951 } 1952 1953 ret = strbuf_detach(&buf, NULL); 1954 out: 1955 strbuf_release(&buf); 1956 return ret; 1957 } 1958 1959 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref, 1960 struct strbuf *buf, int depth) 1961 { 1962 int err; 1963 if (ref->next) { 1964 depth = __synthesize_probe_trace_arg_ref(ref->next, buf, 1965 depth + 1); 1966 if (depth < 0) 1967 return depth; 1968 } 1969 err = strbuf_addf(buf, "%+ld(", ref->offset); 1970 return (err < 0) ? err : depth; 1971 } 1972 1973 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg, 1974 struct strbuf *buf) 1975 { 1976 struct probe_trace_arg_ref *ref = arg->ref; 1977 int depth = 0, err; 1978 1979 /* Argument name or separator */ 1980 if (arg->name) 1981 err = strbuf_addf(buf, " %s=", arg->name); 1982 else 1983 err = strbuf_addch(buf, ' '); 1984 if (err) 1985 return err; 1986 1987 /* Special case: @XXX */ 1988 if (arg->value[0] == '@' && arg->ref) 1989 ref = ref->next; 1990 1991 /* Dereferencing arguments */ 1992 if (ref) { 1993 depth = __synthesize_probe_trace_arg_ref(ref, buf, 1); 1994 if (depth < 0) 1995 return depth; 1996 } 1997 1998 /* Print argument value */ 1999 if (arg->value[0] == '@' && arg->ref) 2000 err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset); 2001 else 2002 err = strbuf_addstr(buf, arg->value); 2003 2004 /* Closing */ 2005 while (!err && depth--) 2006 err = strbuf_addch(buf, ')'); 2007 2008 /* Print argument type */ 2009 if (!err && arg->type) 2010 err = strbuf_addf(buf, ":%s", arg->type); 2011 2012 return err; 2013 } 2014 2015 char *synthesize_probe_trace_command(struct probe_trace_event *tev) 2016 { 2017 struct probe_trace_point *tp = &tev->point; 2018 struct strbuf buf; 2019 char *ret = NULL; 2020 int i, err; 2021 2022 /* Uprobes must have tp->module */ 2023 if (tev->uprobes && !tp->module) 2024 return NULL; 2025 2026 if (strbuf_init(&buf, 32) < 0) 2027 return NULL; 2028 2029 if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p', 2030 tev->group, tev->event) < 0) 2031 goto error; 2032 /* 2033 * If tp->address == 0, then this point must be a 2034 * absolute address uprobe. 2035 * try_to_find_absolute_address() should have made 2036 * tp->symbol to "0x0". 2037 */ 2038 if (tev->uprobes && !tp->address) { 2039 if (!tp->symbol || strcmp(tp->symbol, "0x0")) 2040 goto error; 2041 } 2042 2043 /* Use the tp->address for uprobes */ 2044 if (tev->uprobes) 2045 err = strbuf_addf(&buf, "%s:0x%lx", tp->module, tp->address); 2046 else if (!strncmp(tp->symbol, "0x", 2)) 2047 /* Absolute address. See try_to_find_absolute_address() */ 2048 err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "", 2049 tp->module ? ":" : "", tp->address); 2050 else 2051 err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "", 2052 tp->module ? ":" : "", tp->symbol, tp->offset); 2053 if (err) 2054 goto error; 2055 2056 for (i = 0; i < tev->nargs; i++) 2057 if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0) 2058 goto error; 2059 2060 ret = strbuf_detach(&buf, NULL); 2061 error: 2062 strbuf_release(&buf); 2063 return ret; 2064 } 2065 2066 static int find_perf_probe_point_from_map(struct probe_trace_point *tp, 2067 struct perf_probe_point *pp, 2068 bool is_kprobe) 2069 { 2070 struct symbol *sym = NULL; 2071 struct map *map = NULL; 2072 u64 addr = tp->address; 2073 int ret = -ENOENT; 2074 2075 if (!is_kprobe) { 2076 map = dso__new_map(tp->module); 2077 if (!map) 2078 goto out; 2079 sym = map__find_symbol(map, addr); 2080 } else { 2081 if (tp->symbol && !addr) { 2082 if (kernel_get_symbol_address_by_name(tp->symbol, 2083 &addr, true, false) < 0) 2084 goto out; 2085 } 2086 if (addr) { 2087 addr += tp->offset; 2088 sym = machine__find_kernel_symbol(host_machine, addr, &map); 2089 } 2090 } 2091 2092 if (!sym) 2093 goto out; 2094 2095 pp->retprobe = tp->retprobe; 2096 pp->offset = addr - map->unmap_ip(map, sym->start); 2097 pp->function = strdup(sym->name); 2098 ret = pp->function ? 0 : -ENOMEM; 2099 2100 out: 2101 if (map && !is_kprobe) { 2102 map__put(map); 2103 } 2104 2105 return ret; 2106 } 2107 2108 static int convert_to_perf_probe_point(struct probe_trace_point *tp, 2109 struct perf_probe_point *pp, 2110 bool is_kprobe) 2111 { 2112 char buf[128]; 2113 int ret; 2114 2115 ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe); 2116 if (!ret) 2117 return 0; 2118 ret = find_perf_probe_point_from_map(tp, pp, is_kprobe); 2119 if (!ret) 2120 return 0; 2121 2122 pr_debug("Failed to find probe point from both of dwarf and map.\n"); 2123 2124 if (tp->symbol) { 2125 pp->function = strdup(tp->symbol); 2126 pp->offset = tp->offset; 2127 } else { 2128 ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address); 2129 if (ret < 0) 2130 return ret; 2131 pp->function = strdup(buf); 2132 pp->offset = 0; 2133 } 2134 if (pp->function == NULL) 2135 return -ENOMEM; 2136 2137 pp->retprobe = tp->retprobe; 2138 2139 return 0; 2140 } 2141 2142 static int convert_to_perf_probe_event(struct probe_trace_event *tev, 2143 struct perf_probe_event *pev, bool is_kprobe) 2144 { 2145 struct strbuf buf = STRBUF_INIT; 2146 int i, ret; 2147 2148 /* Convert event/group name */ 2149 pev->event = strdup(tev->event); 2150 pev->group = strdup(tev->group); 2151 if (pev->event == NULL || pev->group == NULL) 2152 return -ENOMEM; 2153 2154 /* Convert trace_point to probe_point */ 2155 ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe); 2156 if (ret < 0) 2157 return ret; 2158 2159 /* Convert trace_arg to probe_arg */ 2160 pev->nargs = tev->nargs; 2161 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs); 2162 if (pev->args == NULL) 2163 return -ENOMEM; 2164 for (i = 0; i < tev->nargs && ret >= 0; i++) { 2165 if (tev->args[i].name) 2166 pev->args[i].name = strdup(tev->args[i].name); 2167 else { 2168 if ((ret = strbuf_init(&buf, 32)) < 0) 2169 goto error; 2170 ret = synthesize_probe_trace_arg(&tev->args[i], &buf); 2171 pev->args[i].name = strbuf_detach(&buf, NULL); 2172 } 2173 if (pev->args[i].name == NULL && ret >= 0) 2174 ret = -ENOMEM; 2175 } 2176 error: 2177 if (ret < 0) 2178 clear_perf_probe_event(pev); 2179 2180 return ret; 2181 } 2182 2183 void clear_perf_probe_event(struct perf_probe_event *pev) 2184 { 2185 struct perf_probe_arg_field *field, *next; 2186 int i; 2187 2188 free(pev->event); 2189 free(pev->group); 2190 free(pev->target); 2191 clear_perf_probe_point(&pev->point); 2192 2193 for (i = 0; i < pev->nargs; i++) { 2194 free(pev->args[i].name); 2195 free(pev->args[i].var); 2196 free(pev->args[i].type); 2197 field = pev->args[i].field; 2198 while (field) { 2199 next = field->next; 2200 zfree(&field->name); 2201 free(field); 2202 field = next; 2203 } 2204 } 2205 free(pev->args); 2206 memset(pev, 0, sizeof(*pev)); 2207 } 2208 2209 #define strdup_or_goto(str, label) \ 2210 ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; }) 2211 2212 static int perf_probe_point__copy(struct perf_probe_point *dst, 2213 struct perf_probe_point *src) 2214 { 2215 dst->file = strdup_or_goto(src->file, out_err); 2216 dst->function = strdup_or_goto(src->function, out_err); 2217 dst->lazy_line = strdup_or_goto(src->lazy_line, out_err); 2218 dst->line = src->line; 2219 dst->retprobe = src->retprobe; 2220 dst->offset = src->offset; 2221 return 0; 2222 2223 out_err: 2224 clear_perf_probe_point(dst); 2225 return -ENOMEM; 2226 } 2227 2228 static int perf_probe_arg__copy(struct perf_probe_arg *dst, 2229 struct perf_probe_arg *src) 2230 { 2231 struct perf_probe_arg_field *field, **ppfield; 2232 2233 dst->name = strdup_or_goto(src->name, out_err); 2234 dst->var = strdup_or_goto(src->var, out_err); 2235 dst->type = strdup_or_goto(src->type, out_err); 2236 2237 field = src->field; 2238 ppfield = &(dst->field); 2239 while (field) { 2240 *ppfield = zalloc(sizeof(*field)); 2241 if (!*ppfield) 2242 goto out_err; 2243 (*ppfield)->name = strdup_or_goto(field->name, out_err); 2244 (*ppfield)->index = field->index; 2245 (*ppfield)->ref = field->ref; 2246 field = field->next; 2247 ppfield = &((*ppfield)->next); 2248 } 2249 return 0; 2250 out_err: 2251 return -ENOMEM; 2252 } 2253 2254 int perf_probe_event__copy(struct perf_probe_event *dst, 2255 struct perf_probe_event *src) 2256 { 2257 int i; 2258 2259 dst->event = strdup_or_goto(src->event, out_err); 2260 dst->group = strdup_or_goto(src->group, out_err); 2261 dst->target = strdup_or_goto(src->target, out_err); 2262 dst->uprobes = src->uprobes; 2263 2264 if (perf_probe_point__copy(&dst->point, &src->point) < 0) 2265 goto out_err; 2266 2267 dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs); 2268 if (!dst->args) 2269 goto out_err; 2270 dst->nargs = src->nargs; 2271 2272 for (i = 0; i < src->nargs; i++) 2273 if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0) 2274 goto out_err; 2275 return 0; 2276 2277 out_err: 2278 clear_perf_probe_event(dst); 2279 return -ENOMEM; 2280 } 2281 2282 void clear_probe_trace_event(struct probe_trace_event *tev) 2283 { 2284 struct probe_trace_arg_ref *ref, *next; 2285 int i; 2286 2287 free(tev->event); 2288 free(tev->group); 2289 free(tev->point.symbol); 2290 free(tev->point.realname); 2291 free(tev->point.module); 2292 for (i = 0; i < tev->nargs; i++) { 2293 free(tev->args[i].name); 2294 free(tev->args[i].value); 2295 free(tev->args[i].type); 2296 ref = tev->args[i].ref; 2297 while (ref) { 2298 next = ref->next; 2299 free(ref); 2300 ref = next; 2301 } 2302 } 2303 free(tev->args); 2304 memset(tev, 0, sizeof(*tev)); 2305 } 2306 2307 struct kprobe_blacklist_node { 2308 struct list_head list; 2309 unsigned long start; 2310 unsigned long end; 2311 char *symbol; 2312 }; 2313 2314 static void kprobe_blacklist__delete(struct list_head *blacklist) 2315 { 2316 struct kprobe_blacklist_node *node; 2317 2318 while (!list_empty(blacklist)) { 2319 node = list_first_entry(blacklist, 2320 struct kprobe_blacklist_node, list); 2321 list_del(&node->list); 2322 free(node->symbol); 2323 free(node); 2324 } 2325 } 2326 2327 static int kprobe_blacklist__load(struct list_head *blacklist) 2328 { 2329 struct kprobe_blacklist_node *node; 2330 const char *__debugfs = debugfs__mountpoint(); 2331 char buf[PATH_MAX], *p; 2332 FILE *fp; 2333 int ret; 2334 2335 if (__debugfs == NULL) 2336 return -ENOTSUP; 2337 2338 ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs); 2339 if (ret < 0) 2340 return ret; 2341 2342 fp = fopen(buf, "r"); 2343 if (!fp) 2344 return -errno; 2345 2346 ret = 0; 2347 while (fgets(buf, PATH_MAX, fp)) { 2348 node = zalloc(sizeof(*node)); 2349 if (!node) { 2350 ret = -ENOMEM; 2351 break; 2352 } 2353 INIT_LIST_HEAD(&node->list); 2354 list_add_tail(&node->list, blacklist); 2355 if (sscanf(buf, "0x%lx-0x%lx", &node->start, &node->end) != 2) { 2356 ret = -EINVAL; 2357 break; 2358 } 2359 p = strchr(buf, '\t'); 2360 if (p) { 2361 p++; 2362 if (p[strlen(p) - 1] == '\n') 2363 p[strlen(p) - 1] = '\0'; 2364 } else 2365 p = (char *)"unknown"; 2366 node->symbol = strdup(p); 2367 if (!node->symbol) { 2368 ret = -ENOMEM; 2369 break; 2370 } 2371 pr_debug2("Blacklist: 0x%lx-0x%lx, %s\n", 2372 node->start, node->end, node->symbol); 2373 ret++; 2374 } 2375 if (ret < 0) 2376 kprobe_blacklist__delete(blacklist); 2377 fclose(fp); 2378 2379 return ret; 2380 } 2381 2382 static struct kprobe_blacklist_node * 2383 kprobe_blacklist__find_by_address(struct list_head *blacklist, 2384 unsigned long address) 2385 { 2386 struct kprobe_blacklist_node *node; 2387 2388 list_for_each_entry(node, blacklist, list) { 2389 if (node->start <= address && address < node->end) 2390 return node; 2391 } 2392 2393 return NULL; 2394 } 2395 2396 static LIST_HEAD(kprobe_blacklist); 2397 2398 static void kprobe_blacklist__init(void) 2399 { 2400 if (!list_empty(&kprobe_blacklist)) 2401 return; 2402 2403 if (kprobe_blacklist__load(&kprobe_blacklist) < 0) 2404 pr_debug("No kprobe blacklist support, ignored\n"); 2405 } 2406 2407 static void kprobe_blacklist__release(void) 2408 { 2409 kprobe_blacklist__delete(&kprobe_blacklist); 2410 } 2411 2412 static bool kprobe_blacklist__listed(unsigned long address) 2413 { 2414 return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address); 2415 } 2416 2417 static int perf_probe_event__sprintf(const char *group, const char *event, 2418 struct perf_probe_event *pev, 2419 const char *module, 2420 struct strbuf *result) 2421 { 2422 int i, ret; 2423 char *buf; 2424 2425 if (asprintf(&buf, "%s:%s", group, event) < 0) 2426 return -errno; 2427 ret = strbuf_addf(result, " %-20s (on ", buf); 2428 free(buf); 2429 if (ret) 2430 return ret; 2431 2432 /* Synthesize only event probe point */ 2433 buf = synthesize_perf_probe_point(&pev->point); 2434 if (!buf) 2435 return -ENOMEM; 2436 ret = strbuf_addstr(result, buf); 2437 free(buf); 2438 2439 if (!ret && module) 2440 ret = strbuf_addf(result, " in %s", module); 2441 2442 if (!ret && pev->nargs > 0) { 2443 ret = strbuf_add(result, " with", 5); 2444 for (i = 0; !ret && i < pev->nargs; i++) { 2445 buf = synthesize_perf_probe_arg(&pev->args[i]); 2446 if (!buf) 2447 return -ENOMEM; 2448 ret = strbuf_addf(result, " %s", buf); 2449 free(buf); 2450 } 2451 } 2452 if (!ret) 2453 ret = strbuf_addch(result, ')'); 2454 2455 return ret; 2456 } 2457 2458 /* Show an event */ 2459 int show_perf_probe_event(const char *group, const char *event, 2460 struct perf_probe_event *pev, 2461 const char *module, bool use_stdout) 2462 { 2463 struct strbuf buf = STRBUF_INIT; 2464 int ret; 2465 2466 ret = perf_probe_event__sprintf(group, event, pev, module, &buf); 2467 if (ret >= 0) { 2468 if (use_stdout) 2469 printf("%s\n", buf.buf); 2470 else 2471 pr_info("%s\n", buf.buf); 2472 } 2473 strbuf_release(&buf); 2474 2475 return ret; 2476 } 2477 2478 static bool filter_probe_trace_event(struct probe_trace_event *tev, 2479 struct strfilter *filter) 2480 { 2481 char tmp[128]; 2482 2483 /* At first, check the event name itself */ 2484 if (strfilter__compare(filter, tev->event)) 2485 return true; 2486 2487 /* Next, check the combination of name and group */ 2488 if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0) 2489 return false; 2490 return strfilter__compare(filter, tmp); 2491 } 2492 2493 static int __show_perf_probe_events(int fd, bool is_kprobe, 2494 struct strfilter *filter) 2495 { 2496 int ret = 0; 2497 struct probe_trace_event tev; 2498 struct perf_probe_event pev; 2499 struct strlist *rawlist; 2500 struct str_node *ent; 2501 2502 memset(&tev, 0, sizeof(tev)); 2503 memset(&pev, 0, sizeof(pev)); 2504 2505 rawlist = probe_file__get_rawlist(fd); 2506 if (!rawlist) 2507 return -ENOMEM; 2508 2509 strlist__for_each_entry(ent, rawlist) { 2510 ret = parse_probe_trace_command(ent->s, &tev); 2511 if (ret >= 0) { 2512 if (!filter_probe_trace_event(&tev, filter)) 2513 goto next; 2514 ret = convert_to_perf_probe_event(&tev, &pev, 2515 is_kprobe); 2516 if (ret < 0) 2517 goto next; 2518 ret = show_perf_probe_event(pev.group, pev.event, 2519 &pev, tev.point.module, 2520 true); 2521 } 2522 next: 2523 clear_perf_probe_event(&pev); 2524 clear_probe_trace_event(&tev); 2525 if (ret < 0) 2526 break; 2527 } 2528 strlist__delete(rawlist); 2529 /* Cleanup cached debuginfo if needed */ 2530 debuginfo_cache__exit(); 2531 2532 return ret; 2533 } 2534 2535 /* List up current perf-probe events */ 2536 int show_perf_probe_events(struct strfilter *filter) 2537 { 2538 int kp_fd, up_fd, ret; 2539 2540 setup_pager(); 2541 2542 if (probe_conf.cache) 2543 return probe_cache__show_all_caches(filter); 2544 2545 ret = init_probe_symbol_maps(false); 2546 if (ret < 0) 2547 return ret; 2548 2549 ret = probe_file__open_both(&kp_fd, &up_fd, 0); 2550 if (ret < 0) 2551 return ret; 2552 2553 if (kp_fd >= 0) 2554 ret = __show_perf_probe_events(kp_fd, true, filter); 2555 if (up_fd >= 0 && ret >= 0) 2556 ret = __show_perf_probe_events(up_fd, false, filter); 2557 if (kp_fd > 0) 2558 close(kp_fd); 2559 if (up_fd > 0) 2560 close(up_fd); 2561 exit_probe_symbol_maps(); 2562 2563 return ret; 2564 } 2565 2566 static int get_new_event_name(char *buf, size_t len, const char *base, 2567 struct strlist *namelist, bool ret_event, 2568 bool allow_suffix) 2569 { 2570 int i, ret; 2571 char *p, *nbase; 2572 2573 if (*base == '.') 2574 base++; 2575 nbase = strdup(base); 2576 if (!nbase) 2577 return -ENOMEM; 2578 2579 /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */ 2580 p = strpbrk(nbase, ".@"); 2581 if (p && p != nbase) 2582 *p = '\0'; 2583 2584 /* Try no suffix number */ 2585 ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : ""); 2586 if (ret < 0) { 2587 pr_debug("snprintf() failed: %d\n", ret); 2588 goto out; 2589 } 2590 if (!strlist__has_entry(namelist, buf)) 2591 goto out; 2592 2593 if (!allow_suffix) { 2594 pr_warning("Error: event \"%s\" already exists.\n" 2595 " Hint: Remove existing event by 'perf probe -d'\n" 2596 " or force duplicates by 'perf probe -f'\n" 2597 " or set 'force=yes' in BPF source.\n", 2598 buf); 2599 ret = -EEXIST; 2600 goto out; 2601 } 2602 2603 /* Try to add suffix */ 2604 for (i = 1; i < MAX_EVENT_INDEX; i++) { 2605 ret = e_snprintf(buf, len, "%s_%d", nbase, i); 2606 if (ret < 0) { 2607 pr_debug("snprintf() failed: %d\n", ret); 2608 goto out; 2609 } 2610 if (!strlist__has_entry(namelist, buf)) 2611 break; 2612 } 2613 if (i == MAX_EVENT_INDEX) { 2614 pr_warning("Too many events are on the same function.\n"); 2615 ret = -ERANGE; 2616 } 2617 2618 out: 2619 free(nbase); 2620 2621 /* Final validation */ 2622 if (ret >= 0 && !is_c_func_name(buf)) { 2623 pr_warning("Internal error: \"%s\" is an invalid event name.\n", 2624 buf); 2625 ret = -EINVAL; 2626 } 2627 2628 return ret; 2629 } 2630 2631 /* Warn if the current kernel's uprobe implementation is old */ 2632 static void warn_uprobe_event_compat(struct probe_trace_event *tev) 2633 { 2634 int i; 2635 char *buf = synthesize_probe_trace_command(tev); 2636 2637 /* Old uprobe event doesn't support memory dereference */ 2638 if (!tev->uprobes || tev->nargs == 0 || !buf) 2639 goto out; 2640 2641 for (i = 0; i < tev->nargs; i++) 2642 if (strglobmatch(tev->args[i].value, "[$@+-]*")) { 2643 pr_warning("Please upgrade your kernel to at least " 2644 "3.14 to have access to feature %s\n", 2645 tev->args[i].value); 2646 break; 2647 } 2648 out: 2649 free(buf); 2650 } 2651 2652 /* Set new name from original perf_probe_event and namelist */ 2653 static int probe_trace_event__set_name(struct probe_trace_event *tev, 2654 struct perf_probe_event *pev, 2655 struct strlist *namelist, 2656 bool allow_suffix) 2657 { 2658 const char *event, *group; 2659 char buf[64]; 2660 int ret; 2661 2662 /* If probe_event or trace_event already have the name, reuse it */ 2663 if (pev->event && !pev->sdt) 2664 event = pev->event; 2665 else if (tev->event) 2666 event = tev->event; 2667 else { 2668 /* Or generate new one from probe point */ 2669 if (pev->point.function && 2670 (strncmp(pev->point.function, "0x", 2) != 0) && 2671 !strisglob(pev->point.function)) 2672 event = pev->point.function; 2673 else 2674 event = tev->point.realname; 2675 } 2676 if (pev->group && !pev->sdt) 2677 group = pev->group; 2678 else if (tev->group) 2679 group = tev->group; 2680 else 2681 group = PERFPROBE_GROUP; 2682 2683 /* Get an unused new event name */ 2684 ret = get_new_event_name(buf, 64, event, namelist, 2685 tev->point.retprobe, allow_suffix); 2686 if (ret < 0) 2687 return ret; 2688 2689 event = buf; 2690 2691 tev->event = strdup(event); 2692 tev->group = strdup(group); 2693 if (tev->event == NULL || tev->group == NULL) 2694 return -ENOMEM; 2695 2696 /* Add added event name to namelist */ 2697 strlist__add(namelist, event); 2698 return 0; 2699 } 2700 2701 static int __open_probe_file_and_namelist(bool uprobe, 2702 struct strlist **namelist) 2703 { 2704 int fd; 2705 2706 fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0)); 2707 if (fd < 0) 2708 return fd; 2709 2710 /* Get current event names */ 2711 *namelist = probe_file__get_namelist(fd); 2712 if (!(*namelist)) { 2713 pr_debug("Failed to get current event list.\n"); 2714 close(fd); 2715 return -ENOMEM; 2716 } 2717 return fd; 2718 } 2719 2720 static int __add_probe_trace_events(struct perf_probe_event *pev, 2721 struct probe_trace_event *tevs, 2722 int ntevs, bool allow_suffix) 2723 { 2724 int i, fd[2] = {-1, -1}, up, ret; 2725 struct probe_trace_event *tev = NULL; 2726 struct probe_cache *cache = NULL; 2727 struct strlist *namelist[2] = {NULL, NULL}; 2728 struct nscookie nsc; 2729 2730 up = pev->uprobes ? 1 : 0; 2731 fd[up] = __open_probe_file_and_namelist(up, &namelist[up]); 2732 if (fd[up] < 0) 2733 return fd[up]; 2734 2735 ret = 0; 2736 for (i = 0; i < ntevs; i++) { 2737 tev = &tevs[i]; 2738 up = tev->uprobes ? 1 : 0; 2739 if (fd[up] == -1) { /* Open the kprobe/uprobe_events */ 2740 fd[up] = __open_probe_file_and_namelist(up, 2741 &namelist[up]); 2742 if (fd[up] < 0) 2743 goto close_out; 2744 } 2745 /* Skip if the symbol is out of .text or blacklisted */ 2746 if (!tev->point.symbol && !pev->uprobes) 2747 continue; 2748 2749 /* Set new name for tev (and update namelist) */ 2750 ret = probe_trace_event__set_name(tev, pev, namelist[up], 2751 allow_suffix); 2752 if (ret < 0) 2753 break; 2754 2755 nsinfo__mountns_enter(pev->nsi, &nsc); 2756 ret = probe_file__add_event(fd[up], tev); 2757 nsinfo__mountns_exit(&nsc); 2758 if (ret < 0) 2759 break; 2760 2761 /* 2762 * Probes after the first probe which comes from same 2763 * user input are always allowed to add suffix, because 2764 * there might be several addresses corresponding to 2765 * one code line. 2766 */ 2767 allow_suffix = true; 2768 } 2769 if (ret == -EINVAL && pev->uprobes) 2770 warn_uprobe_event_compat(tev); 2771 if (ret == 0 && probe_conf.cache) { 2772 cache = probe_cache__new(pev->target, pev->nsi); 2773 if (!cache || 2774 probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 || 2775 probe_cache__commit(cache) < 0) 2776 pr_warning("Failed to add event to probe cache\n"); 2777 probe_cache__delete(cache); 2778 } 2779 2780 close_out: 2781 for (up = 0; up < 2; up++) { 2782 strlist__delete(namelist[up]); 2783 if (fd[up] >= 0) 2784 close(fd[up]); 2785 } 2786 return ret; 2787 } 2788 2789 static int find_probe_functions(struct map *map, char *name, 2790 struct symbol **syms) 2791 { 2792 int found = 0; 2793 struct symbol *sym; 2794 struct rb_node *tmp; 2795 const char *norm, *ver; 2796 char *buf = NULL; 2797 bool cut_version = true; 2798 2799 if (map__load(map) < 0) 2800 return 0; 2801 2802 /* If user gives a version, don't cut off the version from symbols */ 2803 if (strchr(name, '@')) 2804 cut_version = false; 2805 2806 map__for_each_symbol(map, sym, tmp) { 2807 norm = arch__normalize_symbol_name(sym->name); 2808 if (!norm) 2809 continue; 2810 2811 if (cut_version) { 2812 /* We don't care about default symbol or not */ 2813 ver = strchr(norm, '@'); 2814 if (ver) { 2815 buf = strndup(norm, ver - norm); 2816 if (!buf) 2817 return -ENOMEM; 2818 norm = buf; 2819 } 2820 } 2821 2822 if (strglobmatch(norm, name)) { 2823 found++; 2824 if (syms && found < probe_conf.max_probes) 2825 syms[found - 1] = sym; 2826 } 2827 if (buf) 2828 zfree(&buf); 2829 } 2830 2831 return found; 2832 } 2833 2834 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, 2835 struct probe_trace_event *tev __maybe_unused, 2836 struct map *map __maybe_unused, 2837 struct symbol *sym __maybe_unused) { } 2838 2839 /* 2840 * Find probe function addresses from map. 2841 * Return an error or the number of found probe_trace_event 2842 */ 2843 static int find_probe_trace_events_from_map(struct perf_probe_event *pev, 2844 struct probe_trace_event **tevs) 2845 { 2846 struct map *map = NULL; 2847 struct ref_reloc_sym *reloc_sym = NULL; 2848 struct symbol *sym; 2849 struct symbol **syms = NULL; 2850 struct probe_trace_event *tev; 2851 struct perf_probe_point *pp = &pev->point; 2852 struct probe_trace_point *tp; 2853 int num_matched_functions; 2854 int ret, i, j, skipped = 0; 2855 char *mod_name; 2856 2857 map = get_target_map(pev->target, pev->nsi, pev->uprobes); 2858 if (!map) { 2859 ret = -EINVAL; 2860 goto out; 2861 } 2862 2863 syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes); 2864 if (!syms) { 2865 ret = -ENOMEM; 2866 goto out; 2867 } 2868 2869 /* 2870 * Load matched symbols: Since the different local symbols may have 2871 * same name but different addresses, this lists all the symbols. 2872 */ 2873 num_matched_functions = find_probe_functions(map, pp->function, syms); 2874 if (num_matched_functions <= 0) { 2875 pr_err("Failed to find symbol %s in %s\n", pp->function, 2876 pev->target ? : "kernel"); 2877 ret = -ENOENT; 2878 goto out; 2879 } else if (num_matched_functions > probe_conf.max_probes) { 2880 pr_err("Too many functions matched in %s\n", 2881 pev->target ? : "kernel"); 2882 ret = -E2BIG; 2883 goto out; 2884 } 2885 2886 /* Note that the symbols in the kmodule are not relocated */ 2887 if (!pev->uprobes && !pev->target && 2888 (!pp->retprobe || kretprobe_offset_is_supported())) { 2889 reloc_sym = kernel_get_ref_reloc_sym(); 2890 if (!reloc_sym) { 2891 pr_warning("Relocated base symbol is not found!\n"); 2892 ret = -EINVAL; 2893 goto out; 2894 } 2895 } 2896 2897 /* Setup result trace-probe-events */ 2898 *tevs = zalloc(sizeof(*tev) * num_matched_functions); 2899 if (!*tevs) { 2900 ret = -ENOMEM; 2901 goto out; 2902 } 2903 2904 ret = 0; 2905 2906 for (j = 0; j < num_matched_functions; j++) { 2907 sym = syms[j]; 2908 2909 tev = (*tevs) + ret; 2910 tp = &tev->point; 2911 if (ret == num_matched_functions) { 2912 pr_warning("Too many symbols are listed. Skip it.\n"); 2913 break; 2914 } 2915 ret++; 2916 2917 if (pp->offset > sym->end - sym->start) { 2918 pr_warning("Offset %ld is bigger than the size of %s\n", 2919 pp->offset, sym->name); 2920 ret = -ENOENT; 2921 goto err_out; 2922 } 2923 /* Add one probe point */ 2924 tp->address = map->unmap_ip(map, sym->start) + pp->offset; 2925 2926 /* Check the kprobe (not in module) is within .text */ 2927 if (!pev->uprobes && !pev->target && 2928 kprobe_warn_out_range(sym->name, tp->address)) { 2929 tp->symbol = NULL; /* Skip it */ 2930 skipped++; 2931 } else if (reloc_sym) { 2932 tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out); 2933 tp->offset = tp->address - reloc_sym->addr; 2934 } else { 2935 tp->symbol = strdup_or_goto(sym->name, nomem_out); 2936 tp->offset = pp->offset; 2937 } 2938 tp->realname = strdup_or_goto(sym->name, nomem_out); 2939 2940 tp->retprobe = pp->retprobe; 2941 if (pev->target) { 2942 if (pev->uprobes) { 2943 tev->point.module = strdup_or_goto(pev->target, 2944 nomem_out); 2945 } else { 2946 mod_name = find_module_name(pev->target); 2947 tev->point.module = 2948 strdup(mod_name ? mod_name : pev->target); 2949 free(mod_name); 2950 if (!tev->point.module) 2951 goto nomem_out; 2952 } 2953 } 2954 tev->uprobes = pev->uprobes; 2955 tev->nargs = pev->nargs; 2956 if (tev->nargs) { 2957 tev->args = zalloc(sizeof(struct probe_trace_arg) * 2958 tev->nargs); 2959 if (tev->args == NULL) 2960 goto nomem_out; 2961 } 2962 for (i = 0; i < tev->nargs; i++) { 2963 if (pev->args[i].name) 2964 tev->args[i].name = 2965 strdup_or_goto(pev->args[i].name, 2966 nomem_out); 2967 2968 tev->args[i].value = strdup_or_goto(pev->args[i].var, 2969 nomem_out); 2970 if (pev->args[i].type) 2971 tev->args[i].type = 2972 strdup_or_goto(pev->args[i].type, 2973 nomem_out); 2974 } 2975 arch__fix_tev_from_maps(pev, tev, map, sym); 2976 } 2977 if (ret == skipped) { 2978 ret = -ENOENT; 2979 goto err_out; 2980 } 2981 2982 out: 2983 map__put(map); 2984 free(syms); 2985 return ret; 2986 2987 nomem_out: 2988 ret = -ENOMEM; 2989 err_out: 2990 clear_probe_trace_events(*tevs, num_matched_functions); 2991 zfree(tevs); 2992 goto out; 2993 } 2994 2995 static int try_to_find_absolute_address(struct perf_probe_event *pev, 2996 struct probe_trace_event **tevs) 2997 { 2998 struct perf_probe_point *pp = &pev->point; 2999 struct probe_trace_event *tev; 3000 struct probe_trace_point *tp; 3001 int i, err; 3002 3003 if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2))) 3004 return -EINVAL; 3005 if (perf_probe_event_need_dwarf(pev)) 3006 return -EINVAL; 3007 3008 /* 3009 * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at 3010 * absolute address. 3011 * 3012 * Only one tev can be generated by this. 3013 */ 3014 *tevs = zalloc(sizeof(*tev)); 3015 if (!*tevs) 3016 return -ENOMEM; 3017 3018 tev = *tevs; 3019 tp = &tev->point; 3020 3021 /* 3022 * Don't use tp->offset, use address directly, because 3023 * in synthesize_probe_trace_command() address cannot be 3024 * zero. 3025 */ 3026 tp->address = pev->point.abs_address; 3027 tp->retprobe = pp->retprobe; 3028 tev->uprobes = pev->uprobes; 3029 3030 err = -ENOMEM; 3031 /* 3032 * Give it a '0x' leading symbol name. 3033 * In __add_probe_trace_events, a NULL symbol is interpreted as 3034 * invalud. 3035 */ 3036 if (asprintf(&tp->symbol, "0x%lx", tp->address) < 0) 3037 goto errout; 3038 3039 /* For kprobe, check range */ 3040 if ((!tev->uprobes) && 3041 (kprobe_warn_out_range(tev->point.symbol, 3042 tev->point.address))) { 3043 err = -EACCES; 3044 goto errout; 3045 } 3046 3047 if (asprintf(&tp->realname, "abs_%lx", tp->address) < 0) 3048 goto errout; 3049 3050 if (pev->target) { 3051 tp->module = strdup(pev->target); 3052 if (!tp->module) 3053 goto errout; 3054 } 3055 3056 if (tev->group) { 3057 tev->group = strdup(pev->group); 3058 if (!tev->group) 3059 goto errout; 3060 } 3061 3062 if (pev->event) { 3063 tev->event = strdup(pev->event); 3064 if (!tev->event) 3065 goto errout; 3066 } 3067 3068 tev->nargs = pev->nargs; 3069 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs); 3070 if (!tev->args) 3071 goto errout; 3072 3073 for (i = 0; i < tev->nargs; i++) 3074 copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]); 3075 3076 return 1; 3077 3078 errout: 3079 clear_probe_trace_events(*tevs, 1); 3080 *tevs = NULL; 3081 return err; 3082 } 3083 3084 /* Concatinate two arrays */ 3085 static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b) 3086 { 3087 void *ret; 3088 3089 ret = malloc(sz_a + sz_b); 3090 if (ret) { 3091 memcpy(ret, a, sz_a); 3092 memcpy(ret + sz_a, b, sz_b); 3093 } 3094 return ret; 3095 } 3096 3097 static int 3098 concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs, 3099 struct probe_trace_event **tevs2, int ntevs2) 3100 { 3101 struct probe_trace_event *new_tevs; 3102 int ret = 0; 3103 3104 if (*ntevs == 0) { 3105 *tevs = *tevs2; 3106 *ntevs = ntevs2; 3107 *tevs2 = NULL; 3108 return 0; 3109 } 3110 3111 if (*ntevs + ntevs2 > probe_conf.max_probes) 3112 ret = -E2BIG; 3113 else { 3114 /* Concatinate the array of probe_trace_event */ 3115 new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs), 3116 *tevs2, ntevs2 * sizeof(**tevs2)); 3117 if (!new_tevs) 3118 ret = -ENOMEM; 3119 else { 3120 free(*tevs); 3121 *tevs = new_tevs; 3122 *ntevs += ntevs2; 3123 } 3124 } 3125 if (ret < 0) 3126 clear_probe_trace_events(*tevs2, ntevs2); 3127 zfree(tevs2); 3128 3129 return ret; 3130 } 3131 3132 /* 3133 * Try to find probe_trace_event from given probe caches. Return the number 3134 * of cached events found, if an error occurs return the error. 3135 */ 3136 static int find_cached_events(struct perf_probe_event *pev, 3137 struct probe_trace_event **tevs, 3138 const char *target) 3139 { 3140 struct probe_cache *cache; 3141 struct probe_cache_entry *entry; 3142 struct probe_trace_event *tmp_tevs = NULL; 3143 int ntevs = 0; 3144 int ret = 0; 3145 3146 cache = probe_cache__new(target, pev->nsi); 3147 /* Return 0 ("not found") if the target has no probe cache. */ 3148 if (!cache) 3149 return 0; 3150 3151 for_each_probe_cache_entry(entry, cache) { 3152 /* Skip the cache entry which has no name */ 3153 if (!entry->pev.event || !entry->pev.group) 3154 continue; 3155 if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) && 3156 strglobmatch(entry->pev.event, pev->event)) { 3157 ret = probe_cache_entry__get_event(entry, &tmp_tevs); 3158 if (ret > 0) 3159 ret = concat_probe_trace_events(tevs, &ntevs, 3160 &tmp_tevs, ret); 3161 if (ret < 0) 3162 break; 3163 } 3164 } 3165 probe_cache__delete(cache); 3166 if (ret < 0) { 3167 clear_probe_trace_events(*tevs, ntevs); 3168 zfree(tevs); 3169 } else { 3170 ret = ntevs; 3171 if (ntevs > 0 && target && target[0] == '/') 3172 pev->uprobes = true; 3173 } 3174 3175 return ret; 3176 } 3177 3178 /* Try to find probe_trace_event from all probe caches */ 3179 static int find_cached_events_all(struct perf_probe_event *pev, 3180 struct probe_trace_event **tevs) 3181 { 3182 struct probe_trace_event *tmp_tevs = NULL; 3183 struct strlist *bidlist; 3184 struct str_node *nd; 3185 char *pathname; 3186 int ntevs = 0; 3187 int ret; 3188 3189 /* Get the buildid list of all valid caches */ 3190 bidlist = build_id_cache__list_all(true); 3191 if (!bidlist) { 3192 ret = -errno; 3193 pr_debug("Failed to get buildids: %d\n", ret); 3194 return ret; 3195 } 3196 3197 ret = 0; 3198 strlist__for_each_entry(nd, bidlist) { 3199 pathname = build_id_cache__origname(nd->s); 3200 ret = find_cached_events(pev, &tmp_tevs, pathname); 3201 /* In the case of cnt == 0, we just skip it */ 3202 if (ret > 0) 3203 ret = concat_probe_trace_events(tevs, &ntevs, 3204 &tmp_tevs, ret); 3205 free(pathname); 3206 if (ret < 0) 3207 break; 3208 } 3209 strlist__delete(bidlist); 3210 3211 if (ret < 0) { 3212 clear_probe_trace_events(*tevs, ntevs); 3213 zfree(tevs); 3214 } else 3215 ret = ntevs; 3216 3217 return ret; 3218 } 3219 3220 static int find_probe_trace_events_from_cache(struct perf_probe_event *pev, 3221 struct probe_trace_event **tevs) 3222 { 3223 struct probe_cache *cache; 3224 struct probe_cache_entry *entry; 3225 struct probe_trace_event *tev; 3226 struct str_node *node; 3227 int ret, i; 3228 3229 if (pev->sdt) { 3230 /* For SDT/cached events, we use special search functions */ 3231 if (!pev->target) 3232 return find_cached_events_all(pev, tevs); 3233 else 3234 return find_cached_events(pev, tevs, pev->target); 3235 } 3236 cache = probe_cache__new(pev->target, pev->nsi); 3237 if (!cache) 3238 return 0; 3239 3240 entry = probe_cache__find(cache, pev); 3241 if (!entry) { 3242 /* SDT must be in the cache */ 3243 ret = pev->sdt ? -ENOENT : 0; 3244 goto out; 3245 } 3246 3247 ret = strlist__nr_entries(entry->tevlist); 3248 if (ret > probe_conf.max_probes) { 3249 pr_debug("Too many entries matched in the cache of %s\n", 3250 pev->target ? : "kernel"); 3251 ret = -E2BIG; 3252 goto out; 3253 } 3254 3255 *tevs = zalloc(ret * sizeof(*tev)); 3256 if (!*tevs) { 3257 ret = -ENOMEM; 3258 goto out; 3259 } 3260 3261 i = 0; 3262 strlist__for_each_entry(node, entry->tevlist) { 3263 tev = &(*tevs)[i++]; 3264 ret = parse_probe_trace_command(node->s, tev); 3265 if (ret < 0) 3266 goto out; 3267 /* Set the uprobes attribute as same as original */ 3268 tev->uprobes = pev->uprobes; 3269 } 3270 ret = i; 3271 3272 out: 3273 probe_cache__delete(cache); 3274 return ret; 3275 } 3276 3277 static int convert_to_probe_trace_events(struct perf_probe_event *pev, 3278 struct probe_trace_event **tevs) 3279 { 3280 int ret; 3281 3282 if (!pev->group && !pev->sdt) { 3283 /* Set group name if not given */ 3284 if (!pev->uprobes) { 3285 pev->group = strdup(PERFPROBE_GROUP); 3286 ret = pev->group ? 0 : -ENOMEM; 3287 } else 3288 ret = convert_exec_to_group(pev->target, &pev->group); 3289 if (ret != 0) { 3290 pr_warning("Failed to make a group name.\n"); 3291 return ret; 3292 } 3293 } 3294 3295 ret = try_to_find_absolute_address(pev, tevs); 3296 if (ret > 0) 3297 return ret; 3298 3299 /* At first, we need to lookup cache entry */ 3300 ret = find_probe_trace_events_from_cache(pev, tevs); 3301 if (ret > 0 || pev->sdt) /* SDT can be found only in the cache */ 3302 return ret == 0 ? -ENOENT : ret; /* Found in probe cache */ 3303 3304 /* Convert perf_probe_event with debuginfo */ 3305 ret = try_to_find_probe_trace_events(pev, tevs); 3306 if (ret != 0) 3307 return ret; /* Found in debuginfo or got an error */ 3308 3309 return find_probe_trace_events_from_map(pev, tevs); 3310 } 3311 3312 int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3313 { 3314 int i, ret; 3315 3316 /* Loop 1: convert all events */ 3317 for (i = 0; i < npevs; i++) { 3318 /* Init kprobe blacklist if needed */ 3319 if (!pevs[i].uprobes) 3320 kprobe_blacklist__init(); 3321 /* Convert with or without debuginfo */ 3322 ret = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs); 3323 if (ret < 0) 3324 return ret; 3325 pevs[i].ntevs = ret; 3326 } 3327 /* This just release blacklist only if allocated */ 3328 kprobe_blacklist__release(); 3329 3330 return 0; 3331 } 3332 3333 static int show_probe_trace_event(struct probe_trace_event *tev) 3334 { 3335 char *buf = synthesize_probe_trace_command(tev); 3336 3337 if (!buf) { 3338 pr_debug("Failed to synthesize probe trace event.\n"); 3339 return -EINVAL; 3340 } 3341 3342 /* Showing definition always go stdout */ 3343 printf("%s\n", buf); 3344 free(buf); 3345 3346 return 0; 3347 } 3348 3349 int show_probe_trace_events(struct perf_probe_event *pevs, int npevs) 3350 { 3351 struct strlist *namelist = strlist__new(NULL, NULL); 3352 struct probe_trace_event *tev; 3353 struct perf_probe_event *pev; 3354 int i, j, ret = 0; 3355 3356 if (!namelist) 3357 return -ENOMEM; 3358 3359 for (j = 0; j < npevs && !ret; j++) { 3360 pev = &pevs[j]; 3361 for (i = 0; i < pev->ntevs && !ret; i++) { 3362 tev = &pev->tevs[i]; 3363 /* Skip if the symbol is out of .text or blacklisted */ 3364 if (!tev->point.symbol && !pev->uprobes) 3365 continue; 3366 3367 /* Set new name for tev (and update namelist) */ 3368 ret = probe_trace_event__set_name(tev, pev, 3369 namelist, true); 3370 if (!ret) 3371 ret = show_probe_trace_event(tev); 3372 } 3373 } 3374 strlist__delete(namelist); 3375 3376 return ret; 3377 } 3378 3379 int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3380 { 3381 int i, ret = 0; 3382 3383 /* Loop 2: add all events */ 3384 for (i = 0; i < npevs; i++) { 3385 ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs, 3386 pevs[i].ntevs, 3387 probe_conf.force_add); 3388 if (ret < 0) 3389 break; 3390 } 3391 return ret; 3392 } 3393 3394 void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3395 { 3396 int i, j; 3397 struct perf_probe_event *pev; 3398 3399 /* Loop 3: cleanup and free trace events */ 3400 for (i = 0; i < npevs; i++) { 3401 pev = &pevs[i]; 3402 for (j = 0; j < pevs[i].ntevs; j++) 3403 clear_probe_trace_event(&pevs[i].tevs[j]); 3404 zfree(&pevs[i].tevs); 3405 pevs[i].ntevs = 0; 3406 nsinfo__zput(pev->nsi); 3407 clear_perf_probe_event(&pevs[i]); 3408 } 3409 } 3410 3411 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs) 3412 { 3413 int ret; 3414 3415 ret = init_probe_symbol_maps(pevs->uprobes); 3416 if (ret < 0) 3417 return ret; 3418 3419 ret = convert_perf_probe_events(pevs, npevs); 3420 if (ret == 0) 3421 ret = apply_perf_probe_events(pevs, npevs); 3422 3423 cleanup_perf_probe_events(pevs, npevs); 3424 3425 exit_probe_symbol_maps(); 3426 return ret; 3427 } 3428 3429 int del_perf_probe_events(struct strfilter *filter) 3430 { 3431 int ret, ret2, ufd = -1, kfd = -1; 3432 char *str = strfilter__string(filter); 3433 3434 if (!str) 3435 return -EINVAL; 3436 3437 /* Get current event names */ 3438 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW); 3439 if (ret < 0) 3440 goto out; 3441 3442 ret = probe_file__del_events(kfd, filter); 3443 if (ret < 0 && ret != -ENOENT) 3444 goto error; 3445 3446 ret2 = probe_file__del_events(ufd, filter); 3447 if (ret2 < 0 && ret2 != -ENOENT) { 3448 ret = ret2; 3449 goto error; 3450 } 3451 ret = 0; 3452 3453 error: 3454 if (kfd >= 0) 3455 close(kfd); 3456 if (ufd >= 0) 3457 close(ufd); 3458 out: 3459 free(str); 3460 3461 return ret; 3462 } 3463 3464 int show_available_funcs(const char *target, struct nsinfo *nsi, 3465 struct strfilter *_filter, bool user) 3466 { 3467 struct rb_node *nd; 3468 struct map *map; 3469 int ret; 3470 3471 ret = init_probe_symbol_maps(user); 3472 if (ret < 0) 3473 return ret; 3474 3475 /* Get a symbol map */ 3476 map = get_target_map(target, nsi, user); 3477 if (!map) { 3478 pr_err("Failed to get a map for %s\n", (target) ? : "kernel"); 3479 return -EINVAL; 3480 } 3481 3482 ret = map__load(map); 3483 if (ret) { 3484 if (ret == -2) { 3485 char *str = strfilter__string(_filter); 3486 pr_err("Failed to find symbols matched to \"%s\"\n", 3487 str); 3488 free(str); 3489 } else 3490 pr_err("Failed to load symbols in %s\n", 3491 (target) ? : "kernel"); 3492 goto end; 3493 } 3494 if (!dso__sorted_by_name(map->dso)) 3495 dso__sort_by_name(map->dso); 3496 3497 /* Show all (filtered) symbols */ 3498 setup_pager(); 3499 3500 for (nd = rb_first(&map->dso->symbol_names); nd; nd = rb_next(nd)) { 3501 struct symbol_name_rb_node *pos = rb_entry(nd, struct symbol_name_rb_node, rb_node); 3502 3503 if (strfilter__compare(_filter, pos->sym.name)) 3504 printf("%s\n", pos->sym.name); 3505 } 3506 end: 3507 map__put(map); 3508 exit_probe_symbol_maps(); 3509 3510 return ret; 3511 } 3512 3513 int copy_to_probe_trace_arg(struct probe_trace_arg *tvar, 3514 struct perf_probe_arg *pvar) 3515 { 3516 tvar->value = strdup(pvar->var); 3517 if (tvar->value == NULL) 3518 return -ENOMEM; 3519 if (pvar->type) { 3520 tvar->type = strdup(pvar->type); 3521 if (tvar->type == NULL) 3522 return -ENOMEM; 3523 } 3524 if (pvar->name) { 3525 tvar->name = strdup(pvar->name); 3526 if (tvar->name == NULL) 3527 return -ENOMEM; 3528 } else 3529 tvar->name = NULL; 3530 return 0; 3531 } 3532