SAFE public projects git trees. - safe/jmp/linux-2.6/blob - tools/perf/util/symbol.c

   1 #include "util.h"
   2 #include "../perf.h"
   3 #include "string.h"
   4 #include "symbol.h"
   5 #include "thread.h"
   6
   7 #include "debug.h"
   8
   9 #include <libelf.h>
  10 #include <gelf.h>
  11 #include <elf.h>
  12 #include <sys/utsname.h>
  13
  14 enum dso_origin {
  15         DSO__ORIG_KERNEL = 0,
  16         DSO__ORIG_JAVA_JIT,
  17         DSO__ORIG_FEDORA,
  18         DSO__ORIG_UBUNTU,
  19         DSO__ORIG_BUILDID,
  20         DSO__ORIG_DSO,
  21         DSO__ORIG_KMODULE,
  22         DSO__ORIG_NOT_FOUND,
  23 };
  24
  25 static void dsos__add(struct dso *dso);
  26 static struct dso *dsos__find(const char *name);
  27 static struct map *map__new2(u64 start, struct dso *dso);
  28 static void kernel_maps__insert(struct map *map);
  29 unsigned int symbol__priv_size;
  30
  31 static struct rb_root kernel_maps;
  32
  33 static void dso__fixup_sym_end(struct dso *self)
  34 {
  35         struct rb_node *nd, *prevnd = rb_first(&self->syms);
  36         struct symbol *curr, *prev;
  37
  38         if (prevnd == NULL)
  39                 return;
  40
  41         curr = rb_entry(prevnd, struct symbol, rb_node);
  42
  43         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  44                 prev = curr;
  45                 curr = rb_entry(nd, struct symbol, rb_node);
  46
  47                 if (prev->end == prev->start)
  48                         prev->end = curr->start - 1;
  49         }
  50
  51         /* Last entry */
  52         if (curr->end == curr->start)
  53                 curr->end = roundup(curr->start, 4096);
  54 }
  55
  56 static void kernel_maps__fixup_end(void)
  57 {
  58         struct map *prev, *curr;
  59         struct rb_node *nd, *prevnd = rb_first(&kernel_maps);
  60
  61         if (prevnd == NULL)
  62                 return;
  63
  64         curr = rb_entry(prevnd, struct map, rb_node);
  65
  66         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  67                 prev = curr;
  68                 curr = rb_entry(nd, struct map, rb_node);
  69                 prev->end = curr->start - 1;
  70         }
  71
  72         nd = rb_last(&curr->dso->syms);
  73         if (nd) {
  74                 struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
  75                 curr->end = sym->end;
  76         }
  77 }
  78
  79 static struct symbol *symbol__new(u64 start, u64 len, const char *name)
  80 {
  81         size_t namelen = strlen(name) + 1;
  82         struct symbol *self = calloc(1, (symbol__priv_size +
  83                                          sizeof(*self) + namelen));
  84         if (!self)
  85                 return NULL;
  86
  87         if (symbol__priv_size) {
  88                 memset(self, 0, symbol__priv_size);
  89                 self = ((void *)self) + symbol__priv_size;
  90         }
  91         self->start = start;
  92         self->end   = len ? start + len - 1 : start;
  93
  94         pr_debug3("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
  95
  96         memcpy(self->name, name, namelen);
  97
  98         return self;
  99 }
 100
 101 static void symbol__delete(struct symbol *self)
 102 {
 103         free(((void *)self) - symbol__priv_size);
 104 }
 105
 106 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
 107 {
 108         return fprintf(fp, " %llx-%llx %s\n",
 109                        self->start, self->end, self->name);
 110 }
 111
 112 struct dso *dso__new(const char *name)
 113 {
 114         struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
 115
 116         if (self != NULL) {
 117                 strcpy(self->name, name);
 118                 self->long_name = self->name;
 119                 self->short_name = self->name;
 120                 self->syms = RB_ROOT;
 121                 self->find_symbol = dso__find_symbol;
 122                 self->slen_calculated = 0;
 123                 self->origin = DSO__ORIG_NOT_FOUND;
 124                 self->loaded = 0;
 125                 self->has_build_id = 0;
 126         }
 127
 128         return self;
 129 }
 130
 131 static void dso__delete_symbols(struct dso *self)
 132 {
 133         struct symbol *pos;
 134         struct rb_node *next = rb_first(&self->syms);
 135
 136         while (next) {
 137                 pos = rb_entry(next, struct symbol, rb_node);
 138                 next = rb_next(&pos->rb_node);
 139                 rb_erase(&pos->rb_node, &self->syms);
 140                 symbol__delete(pos);
 141         }
 142 }
 143
 144 void dso__delete(struct dso *self)
 145 {
 146         dso__delete_symbols(self);
 147         if (self->long_name != self->name)
 148                 free(self->long_name);
 149         free(self);
 150 }
 151
 152 void dso__set_build_id(struct dso *self, void *build_id)
 153 {
 154         memcpy(self->build_id, build_id, sizeof(self->build_id));
 155         self->has_build_id = 1;
 156 }
 157
 158 static void dso__insert_symbol(struct dso *self, struct symbol *sym)
 159 {
 160         struct rb_node **p = &self->syms.rb_node;
 161         struct rb_node *parent = NULL;
 162         const u64 ip = sym->start;
 163         struct symbol *s;
 164
 165         while (*p != NULL) {
 166                 parent = *p;
 167                 s = rb_entry(parent, struct symbol, rb_node);
 168                 if (ip < s->start)
 169                         p = &(*p)->rb_left;
 170                 else
 171                         p = &(*p)->rb_right;
 172         }
 173         rb_link_node(&sym->rb_node, parent, p);
 174         rb_insert_color(&sym->rb_node, &self->syms);
 175 }
 176
 177 struct symbol *dso__find_symbol(struct dso *self, u64 ip)
 178 {
 179         struct rb_node *n;
 180
 181         if (self == NULL)
 182                 return NULL;
 183
 184         n = self->syms.rb_node;
 185
 186         while (n) {
 187                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 188
 189                 if (ip < s->start)
 190                         n = n->rb_left;
 191                 else if (ip > s->end)
 192                         n = n->rb_right;
 193                 else
 194                         return s;
 195         }
 196
 197         return NULL;
 198 }
 199
 200 int build_id__sprintf(u8 *self, int len, char *bf)
 201 {
 202         char *bid = bf;
 203         u8 *raw = self;
 204         int i;
 205
 206         for (i = 0; i < len; ++i) {
 207                 sprintf(bid, "%02x", *raw);
 208                 ++raw;
 209                 bid += 2;
 210         }
 211
 212         return raw - self;
 213 }
 214
 215 size_t dso__fprintf(struct dso *self, FILE *fp)
 216 {
 217         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
 218         struct rb_node *nd;
 219         size_t ret;
 220
 221         build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
 222         ret = fprintf(fp, "dso: %s (%s)\n", self->short_name, sbuild_id);
 223
 224         for (nd = rb_first(&self->syms); nd; nd = rb_next(nd)) {
 225                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 226                 ret += symbol__fprintf(pos, fp);
 227         }
 228
 229         return ret;
 230 }
 231
 232 /*
 233  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 234  * so that we can in the next step set the symbol ->end address and then
 235  * call kernel_maps__split_kallsyms.
 236  */
 237 static int kernel_maps__load_all_kallsyms(void)
 238 {
 239         char *line = NULL;
 240         size_t n;
 241         FILE *file = fopen("/proc/kallsyms", "r");
 242
 243         if (file == NULL)
 244                 goto out_failure;
 245
 246         while (!feof(file)) {
 247                 u64 start;
 248                 struct symbol *sym;
 249                 int line_len, len;
 250                 char symbol_type;
 251                 char *symbol_name;
 252
 253                 line_len = getline(&line, &n, file);
 254                 if (line_len < 0)
 255                         break;
 256
 257                 if (!line)
 258                         goto out_failure;
 259
 260                 line[--line_len] = '\0'; /* \n */
 261
 262                 len = hex2u64(line, &start);
 263
 264                 len++;
 265                 if (len + 2 >= line_len)
 266                         continue;
 267
 268                 symbol_type = toupper(line[len]);
 269                 /*
 270                  * We're interested only in code ('T'ext)
 271                  */
 272                 if (symbol_type != 'T' && symbol_type != 'W')
 273                         continue;
 274
 275                 symbol_name = line + len + 2;
 276                 /*
 277                  * Will fix up the end later, when we have all symbols sorted.
 278                  */
 279                 sym = symbol__new(start, 0, symbol_name);
 280
 281                 if (sym == NULL)
 282                         goto out_delete_line;
 283
 284                 /*
 285                  * We will pass the symbols to the filter later, in
 286                  * kernel_maps__split_kallsyms, when we have split the
 287                  * maps per module
 288                  */
 289                 dso__insert_symbol(kernel_map->dso, sym);
 290         }
 291
 292         free(line);
 293         fclose(file);
 294
 295         return 0;
 296
 297 out_delete_line:
 298         free(line);
 299 out_failure:
 300         return -1;
 301 }
 302
 303 /*
 304  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 305  * kernel range is broken in several maps, named [kernel].N, as we don't have
 306  * the original ELF section names vmlinux have.
 307  */
 308 static int kernel_maps__split_kallsyms(symbol_filter_t filter, int use_modules)
 309 {
 310         struct map *map = kernel_map;
 311         struct symbol *pos;
 312         int count = 0;
 313         struct rb_node *next = rb_first(&kernel_map->dso->syms);
 314         int kernel_range = 0;
 315
 316         while (next) {
 317                 char *module;
 318
 319                 pos = rb_entry(next, struct symbol, rb_node);
 320                 next = rb_next(&pos->rb_node);
 321
 322                 module = strchr(pos->name, '\t');
 323                 if (module) {
 324                         if (!use_modules)
 325                                 goto delete_symbol;
 326
 327                         *module++ = '\0';
 328
 329                         if (strcmp(map->dso->name, module)) {
 330                                 map = kernel_maps__find_by_dso_name(module);
 331                                 if (!map) {
 332                                         pr_err("/proc/{kallsyms,modules} "
 333                                                "inconsistency!\n");
 334                                         return -1;
 335                                 }
 336                         }
 337                         /*
 338                          * So that we look just like we get from .ko files,
 339                          * i.e. not prelinked, relative to map->start.
 340                          */
 341                         pos->start = map->map_ip(map, pos->start);
 342                         pos->end   = map->map_ip(map, pos->end);
 343                 } else if (map != kernel_map) {
 344                         char dso_name[PATH_MAX];
 345                         struct dso *dso;
 346
 347                         snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
 348                                  kernel_range++);
 349
 350                         dso = dso__new(dso_name);
 351                         if (dso == NULL)
 352                                 return -1;
 353
 354                         map = map__new2(pos->start, dso);
 355                         if (map == NULL) {
 356                                 dso__delete(dso);
 357                                 return -1;
 358                         }
 359
 360                         map->map_ip = map->unmap_ip = identity__map_ip;
 361                         kernel_maps__insert(map);
 362                         ++kernel_range;
 363                 }
 364
 365                 if (filter && filter(map, pos)) {
 366 delete_symbol:
 367                         rb_erase(&pos->rb_node, &kernel_map->dso->syms);
 368                         symbol__delete(pos);
 369                 } else {
 370                         if (map != kernel_map) {
 371                                 rb_erase(&pos->rb_node, &kernel_map->dso->syms);
 372                                 dso__insert_symbol(map->dso, pos);
 373                         }
 374                         count++;
 375                 }
 376         }
 377
 378         return count;
 379 }
 380
 381
 382 static int kernel_maps__load_kallsyms(symbol_filter_t filter, int use_modules)
 383 {
 384         if (kernel_maps__load_all_kallsyms())
 385                 return -1;
 386
 387         dso__fixup_sym_end(kernel_map->dso);
 388
 389         return kernel_maps__split_kallsyms(filter, use_modules);
 390 }
 391
 392 static size_t kernel_maps__fprintf(FILE *fp)
 393 {
 394         size_t printed = fprintf(fp, "Kernel maps:\n");
 395         struct rb_node *nd;
 396
 397         for (nd = rb_first(&kernel_maps); nd; nd = rb_next(nd)) {
 398                 struct map *pos = rb_entry(nd, struct map, rb_node);
 399
 400                 printed += fprintf(fp, "Map:");
 401                 printed += map__fprintf(pos, fp);
 402                 if (verbose > 1) {
 403                         printed += dso__fprintf(pos->dso, fp);
 404                         printed += fprintf(fp, "--\n");
 405                 }
 406         }
 407
 408         return printed + fprintf(fp, "END kernel maps\n");
 409 }
 410
 411 static int dso__load_perf_map(struct dso *self, struct map *map,
 412                               symbol_filter_t filter)
 413 {
 414         char *line = NULL;
 415         size_t n;
 416         FILE *file;
 417         int nr_syms = 0;
 418
 419         file = fopen(self->long_name, "r");
 420         if (file == NULL)
 421                 goto out_failure;
 422
 423         while (!feof(file)) {
 424                 u64 start, size;
 425                 struct symbol *sym;
 426                 int line_len, len;
 427
 428                 line_len = getline(&line, &n, file);
 429                 if (line_len < 0)
 430                         break;
 431
 432                 if (!line)
 433                         goto out_failure;
 434
 435                 line[--line_len] = '\0'; /* \n */
 436
 437                 len = hex2u64(line, &start);
 438
 439                 len++;
 440                 if (len + 2 >= line_len)
 441                         continue;
 442
 443                 len += hex2u64(line + len, &size);
 444
 445                 len++;
 446                 if (len + 2 >= line_len)
 447                         continue;
 448
 449                 sym = symbol__new(start, size, line + len);
 450
 451                 if (sym == NULL)
 452                         goto out_delete_line;
 453
 454                 if (filter && filter(map, sym))
 455                         symbol__delete(sym);
 456                 else {
 457                         dso__insert_symbol(self, sym);
 458                         nr_syms++;
 459                 }
 460         }
 461
 462         free(line);
 463         fclose(file);
 464
 465         return nr_syms;
 466
 467 out_delete_line:
 468         free(line);
 469 out_failure:
 470         return -1;
 471 }
 472
 473 /**
 474  * elf_symtab__for_each_symbol - iterate thru all the symbols
 475  *
 476  * @self: struct elf_symtab instance to iterate
 477  * @idx: uint32_t idx
 478  * @sym: GElf_Sym iterator
 479  */
 480 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
 481         for (idx = 0, gelf_getsym(syms, idx, &sym);\
 482              idx < nr_syms; \
 483              idx++, gelf_getsym(syms, idx, &sym))
 484
 485 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
 486 {
 487         return GELF_ST_TYPE(sym->st_info);
 488 }
 489
 490 static inline int elf_sym__is_function(const GElf_Sym *sym)
 491 {
 492         return elf_sym__type(sym) == STT_FUNC &&
 493                sym->st_name != 0 &&
 494                sym->st_shndx != SHN_UNDEF;
 495 }
 496
 497 static inline int elf_sym__is_label(const GElf_Sym *sym)
 498 {
 499         return elf_sym__type(sym) == STT_NOTYPE &&
 500                 sym->st_name != 0 &&
 501                 sym->st_shndx != SHN_UNDEF &&
 502                 sym->st_shndx != SHN_ABS;
 503 }
 504
 505 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
 506                                         const Elf_Data *secstrs)
 507 {
 508         return secstrs->d_buf + shdr->sh_name;
 509 }
 510
 511 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
 512                                         const Elf_Data *secstrs)
 513 {
 514         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
 515 }
 516
 517 static inline const char *elf_sym__name(const GElf_Sym *sym,
 518                                         const Elf_Data *symstrs)
 519 {
 520         return symstrs->d_buf + sym->st_name;
 521 }
 522
 523 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 524                                     GElf_Shdr *shp, const char *name,
 525                                     size_t *idx)
 526 {
 527         Elf_Scn *sec = NULL;
 528         size_t cnt = 1;
 529
 530         while ((sec = elf_nextscn(elf, sec)) != NULL) {
 531                 char *str;
 532
 533                 gelf_getshdr(sec, shp);
 534                 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
 535                 if (!strcmp(name, str)) {
 536                         if (idx)
 537                                 *idx = cnt;
 538                         break;
 539                 }
 540                 ++cnt;
 541         }
 542
 543         return sec;
 544 }
 545
 546 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
 547         for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
 548              idx < nr_entries; \
 549              ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
 550
 551 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
 552         for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
 553              idx < nr_entries; \
 554              ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
 555
 556 /*
 557  * We need to check if we have a .dynsym, so that we can handle the
 558  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
 559  * .dynsym or .symtab).
 560  * And always look at the original dso, not at debuginfo packages, that
 561  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
 562  */
 563 static int dso__synthesize_plt_symbols(struct  dso *self, struct map *map,
 564                                        symbol_filter_t filter)
 565 {
 566         uint32_t nr_rel_entries, idx;
 567         GElf_Sym sym;
 568         u64 plt_offset;
 569         GElf_Shdr shdr_plt;
 570         struct symbol *f;
 571         GElf_Shdr shdr_rel_plt, shdr_dynsym;
 572         Elf_Data *reldata, *syms, *symstrs;
 573         Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
 574         size_t dynsym_idx;
 575         GElf_Ehdr ehdr;
 576         char sympltname[1024];
 577         Elf *elf;
 578         int nr = 0, symidx, fd, err = 0;
 579
 580         fd = open(self->long_name, O_RDONLY);
 581         if (fd < 0)
 582                 goto out;
 583
 584         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 585         if (elf == NULL)
 586                 goto out_close;
 587
 588         if (gelf_getehdr(elf, &ehdr) == NULL)
 589                 goto out_elf_end;
 590
 591         scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
 592                                          ".dynsym", &dynsym_idx);
 593         if (scn_dynsym == NULL)
 594                 goto out_elf_end;
 595
 596         scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 597                                           ".rela.plt", NULL);
 598         if (scn_plt_rel == NULL) {
 599                 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 600                                                   ".rel.plt", NULL);
 601                 if (scn_plt_rel == NULL)
 602                         goto out_elf_end;
 603         }
 604
 605         err = -1;
 606
 607         if (shdr_rel_plt.sh_link != dynsym_idx)
 608                 goto out_elf_end;
 609
 610         if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
 611                 goto out_elf_end;
 612
 613         /*
 614          * Fetch the relocation section to find the idxes to the GOT
 615          * and the symbols in the .dynsym they refer to.
 616          */
 617         reldata = elf_getdata(scn_plt_rel, NULL);
 618         if (reldata == NULL)
 619                 goto out_elf_end;
 620
 621         syms = elf_getdata(scn_dynsym, NULL);
 622         if (syms == NULL)
 623                 goto out_elf_end;
 624
 625         scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
 626         if (scn_symstrs == NULL)
 627                 goto out_elf_end;
 628
 629         symstrs = elf_getdata(scn_symstrs, NULL);
 630         if (symstrs == NULL)
 631                 goto out_elf_end;
 632
 633         nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
 634         plt_offset = shdr_plt.sh_offset;
 635
 636         if (shdr_rel_plt.sh_type == SHT_RELA) {
 637                 GElf_Rela pos_mem, *pos;
 638
 639                 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
 640                                            nr_rel_entries) {
 641                         symidx = GELF_R_SYM(pos->r_info);
 642                         plt_offset += shdr_plt.sh_entsize;
 643                         gelf_getsym(syms, symidx, &sym);
 644                         snprintf(sympltname, sizeof(sympltname),
 645                                  "%s@plt", elf_sym__name(&sym, symstrs));
 646
 647                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 648                                         sympltname);
 649                         if (!f)
 650                                 goto out_elf_end;
 651
 652                         if (filter && filter(map, f))
 653                                 symbol__delete(f);
 654                         else {
 655                                 dso__insert_symbol(self, f);
 656                                 ++nr;
 657                         }
 658                 }
 659         } else if (shdr_rel_plt.sh_type == SHT_REL) {
 660                 GElf_Rel pos_mem, *pos;
 661                 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
 662                                           nr_rel_entries) {
 663                         symidx = GELF_R_SYM(pos->r_info);
 664                         plt_offset += shdr_plt.sh_entsize;
 665                         gelf_getsym(syms, symidx, &sym);
 666                         snprintf(sympltname, sizeof(sympltname),
 667                                  "%s@plt", elf_sym__name(&sym, symstrs));
 668
 669                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 670                                         sympltname);
 671                         if (!f)
 672                                 goto out_elf_end;
 673
 674                         if (filter && filter(map, f))
 675                                 symbol__delete(f);
 676                         else {
 677                                 dso__insert_symbol(self, f);
 678                                 ++nr;
 679                         }
 680                 }
 681         }
 682
 683         err = 0;
 684 out_elf_end:
 685         elf_end(elf);
 686 out_close:
 687         close(fd);
 688
 689         if (err == 0)
 690                 return nr;
 691 out:
 692         pr_warning("%s: problems reading %s PLT info.\n",
 693                    __func__, self->long_name);
 694         return 0;
 695 }
 696
 697 static int dso__load_sym(struct dso *self, struct map *map, const char *name,
 698                          int fd, symbol_filter_t filter, int kernel,
 699                          int kmodule)
 700 {
 701         struct map *curr_map = map;
 702         struct dso *curr_dso = self;
 703         size_t dso_name_len = strlen(self->short_name);
 704         Elf_Data *symstrs, *secstrs;
 705         uint32_t nr_syms;
 706         int err = -1;
 707         uint32_t idx;
 708         GElf_Ehdr ehdr;
 709         GElf_Shdr shdr;
 710         Elf_Data *syms;
 711         GElf_Sym sym;
 712         Elf_Scn *sec, *sec_strndx;
 713         Elf *elf;
 714         int nr = 0;
 715
 716         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 717         if (elf == NULL) {
 718                 pr_err("%s: cannot read %s ELF file.\n", __func__, name);
 719                 goto out_close;
 720         }
 721
 722         if (gelf_getehdr(elf, &ehdr) == NULL) {
 723                 pr_err("%s: cannot get elf header.\n", __func__);
 724                 goto out_elf_end;
 725         }
 726
 727         sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
 728         if (sec == NULL) {
 729                 sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
 730                 if (sec == NULL)
 731                         goto out_elf_end;
 732         }
 733
 734         syms = elf_getdata(sec, NULL);
 735         if (syms == NULL)
 736                 goto out_elf_end;
 737
 738         sec = elf_getscn(elf, shdr.sh_link);
 739         if (sec == NULL)
 740                 goto out_elf_end;
 741
 742         symstrs = elf_getdata(sec, NULL);
 743         if (symstrs == NULL)
 744                 goto out_elf_end;
 745
 746         sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
 747         if (sec_strndx == NULL)
 748                 goto out_elf_end;
 749
 750         secstrs = elf_getdata(sec_strndx, NULL);
 751         if (secstrs == NULL)
 752                 goto out_elf_end;
 753
 754         nr_syms = shdr.sh_size / shdr.sh_entsize;
 755
 756         memset(&sym, 0, sizeof(sym));
 757         if (!kernel) {
 758                 self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
 759                                 elf_section_by_name(elf, &ehdr, &shdr,
 760                                                      ".gnu.prelink_undo",
 761                                                      NULL) != NULL);
 762         } else self->adjust_symbols = 0;
 763
 764         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
 765                 struct symbol *f;
 766                 const char *elf_name;
 767                 char *demangled = NULL;
 768                 int is_label = elf_sym__is_label(&sym);
 769                 const char *section_name;
 770
 771                 if (!is_label && !elf_sym__is_function(&sym))
 772                         continue;
 773
 774                 sec = elf_getscn(elf, sym.st_shndx);
 775                 if (!sec)
 776                         goto out_elf_end;
 777
 778                 gelf_getshdr(sec, &shdr);
 779
 780                 if (is_label && !elf_sec__is_text(&shdr, secstrs))
 781                         continue;
 782
 783                 elf_name = elf_sym__name(&sym, symstrs);
 784                 section_name = elf_sec__name(&shdr, secstrs);
 785
 786                 if (kernel || kmodule) {
 787                         char dso_name[PATH_MAX];
 788
 789                         if (strcmp(section_name,
 790                                    curr_dso->short_name + dso_name_len) == 0)
 791                                 goto new_symbol;
 792
 793                         if (strcmp(section_name, ".text") == 0) {
 794                                 curr_map = map;
 795                                 curr_dso = self;
 796                                 goto new_symbol;
 797                         }
 798
 799                         snprintf(dso_name, sizeof(dso_name),
 800                                  "%s%s", self->short_name, section_name);
 801
 802                         curr_map = kernel_maps__find_by_dso_name(dso_name);
 803                         if (curr_map == NULL) {
 804                                 u64 start = sym.st_value;
 805
 806                                 if (kmodule)
 807                                         start += map->start + shdr.sh_offset;
 808
 809                                 curr_dso = dso__new(dso_name);
 810                                 if (curr_dso == NULL)
 811                                         goto out_elf_end;
 812                                 curr_map = map__new2(start, curr_dso);
 813                                 if (curr_map == NULL) {
 814                                         dso__delete(curr_dso);
 815                                         goto out_elf_end;
 816                                 }
 817                                 curr_map->map_ip = identity__map_ip;
 818                                 curr_map->unmap_ip = identity__map_ip;
 819                                 curr_dso->origin = DSO__ORIG_KERNEL;
 820                                 kernel_maps__insert(curr_map);
 821                                 dsos__add(curr_dso);
 822                         } else
 823                                 curr_dso = curr_map->dso;
 824
 825                         goto new_symbol;
 826                 }
 827
 828                 if (curr_dso->adjust_symbols) {
 829                         pr_debug2("adjusting symbol: st_value: %Lx sh_addr: "
 830                                   "%Lx sh_offset: %Lx\n", (u64)sym.st_value,
 831                                   (u64)shdr.sh_addr, (u64)shdr.sh_offset);
 832                         sym.st_value -= shdr.sh_addr - shdr.sh_offset;
 833                 }
 834                 /*
 835                  * We need to figure out if the object was created from C++ sources
 836                  * DWARF DW_compile_unit has this, but we don't always have access
 837                  * to it...
 838                  */
 839                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
 840                 if (demangled != NULL)
 841                         elf_name = demangled;
 842 new_symbol:
 843                 f = symbol__new(sym.st_value, sym.st_size, elf_name);
 844                 free(demangled);
 845                 if (!f)
 846                         goto out_elf_end;
 847
 848                 if (filter && filter(curr_map, f))
 849                         symbol__delete(f);
 850                 else {
 851                         dso__insert_symbol(curr_dso, f);
 852                         nr++;
 853                 }
 854         }
 855
 856         /*
 857          * For misannotated, zeroed, ASM function sizes.
 858          */
 859         if (nr > 0)
 860                 dso__fixup_sym_end(self);
 861         err = nr;
 862 out_elf_end:
 863         elf_end(elf);
 864 out_close:
 865         return err;
 866 }
 867
 868 bool fetch_build_id_table(struct list_head *head)
 869 {
 870         bool have_buildid = false;
 871         struct dso *pos;
 872
 873         list_for_each_entry(pos, &dsos, node) {
 874                 struct build_id_list *new;
 875                 struct build_id_event b;
 876                 size_t len;
 877
 878                 if (filename__read_build_id(pos->long_name,
 879                                             &b.build_id,
 880                                             sizeof(b.build_id)) < 0)
 881                         continue;
 882                 have_buildid = true;
 883                 memset(&b.header, 0, sizeof(b.header));
 884                 len = strlen(pos->long_name) + 1;
 885                 len = ALIGN(len, 64);
 886                 b.header.size = sizeof(b) + len;
 887
 888                 new = malloc(sizeof(*new));
 889                 if (!new)
 890                         die("No memory\n");
 891
 892                 memcpy(&new->event, &b, sizeof(b));
 893                 new->dso_name = pos->long_name;
 894                 new->len = len;
 895
 896                 list_add_tail(&new->list, head);
 897         }
 898
 899         return have_buildid;
 900 }
 901
 902 int filename__read_build_id(const char *filename, void *bf, size_t size)
 903 {
 904         int fd, err = -1;
 905         GElf_Ehdr ehdr;
 906         GElf_Shdr shdr;
 907         Elf_Data *build_id_data;
 908         Elf_Scn *sec;
 909         Elf *elf;
 910
 911         if (size < BUILD_ID_SIZE)
 912                 goto out;
 913
 914         fd = open(filename, O_RDONLY);
 915         if (fd < 0)
 916                 goto out;
 917
 918         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 919         if (elf == NULL) {
 920                 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
 921                 goto out_close;
 922         }
 923
 924         if (gelf_getehdr(elf, &ehdr) == NULL) {
 925                 pr_err("%s: cannot get elf header.\n", __func__);
 926                 goto out_elf_end;
 927         }
 928
 929         sec = elf_section_by_name(elf, &ehdr, &shdr,
 930                                   ".note.gnu.build-id", NULL);
 931         if (sec == NULL)
 932                 goto out_elf_end;
 933
 934         build_id_data = elf_getdata(sec, NULL);
 935         if (build_id_data == NULL)
 936                 goto out_elf_end;
 937         memcpy(bf, build_id_data->d_buf + 16, BUILD_ID_SIZE);
 938         err = BUILD_ID_SIZE;
 939 out_elf_end:
 940         elf_end(elf);
 941 out_close:
 942         close(fd);
 943 out:
 944         return err;
 945 }
 946
 947 static char *dso__read_build_id(struct dso *self)
 948 {
 949         int len;
 950         char *build_id = NULL;
 951         unsigned char rawbf[BUILD_ID_SIZE];
 952
 953         len = filename__read_build_id(self->long_name, rawbf, sizeof(rawbf));
 954         if (len < 0)
 955                 goto out;
 956
 957         build_id = malloc(len * 2 + 1);
 958         if (build_id == NULL)
 959                 goto out;
 960
 961         build_id__sprintf(rawbf, len, build_id);
 962 out:
 963         return build_id;
 964 }
 965
 966 char dso__symtab_origin(const struct dso *self)
 967 {
 968         static const char origin[] = {
 969                 [DSO__ORIG_KERNEL] =   'k',
 970                 [DSO__ORIG_JAVA_JIT] = 'j',
 971                 [DSO__ORIG_FEDORA] =   'f',
 972                 [DSO__ORIG_UBUNTU] =   'u',
 973                 [DSO__ORIG_BUILDID] =  'b',
 974                 [DSO__ORIG_DSO] =      'd',
 975                 [DSO__ORIG_KMODULE] =  'K',
 976         };
 977
 978         if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
 979                 return '!';
 980         return origin[self->origin];
 981 }
 982
 983 int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
 984 {
 985         int size = PATH_MAX;
 986         char *name = malloc(size), *build_id = NULL;
 987         int ret = -1;
 988         int fd;
 989
 990         self->loaded = 1;
 991
 992         if (!name)
 993                 return -1;
 994
 995         self->adjust_symbols = 0;
 996
 997         if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
 998                 ret = dso__load_perf_map(self, map, filter);
 999                 self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
1000                                          DSO__ORIG_NOT_FOUND;
1001                 return ret;
1002         }
1003
1004         self->origin = DSO__ORIG_FEDORA - 1;
1005
1006 more:
1007         do {
1008                 int berr = 0;
1009
1010                 self->origin++;
1011                 switch (self->origin) {
1012                 case DSO__ORIG_FEDORA:
1013                         snprintf(name, size, "/usr/lib/debug%s.debug",
1014                                  self->long_name);
1015                         break;
1016                 case DSO__ORIG_UBUNTU:
1017                         snprintf(name, size, "/usr/lib/debug%s",
1018                                  self->long_name);
1019                         break;
1020                 case DSO__ORIG_BUILDID:
1021                         build_id = dso__read_build_id(self);
1022                         if (build_id != NULL) {
1023                                 snprintf(name, size,
1024                                          "/usr/lib/debug/.build-id/%.2s/%s.debug",
1025                                         build_id, build_id + 2);
1026                                 goto compare_build_id;
1027                         }
1028                         self->origin++;
1029                         /* Fall thru */
1030                 case DSO__ORIG_DSO:
1031                         snprintf(name, size, "%s", self->long_name);
1032                         break;
1033
1034                 default:
1035                         goto out;
1036                 }
1037
1038                 if (self->has_build_id) {
1039                         bool match;
1040                         build_id = malloc(BUILD_ID_SIZE);
1041                         if (build_id == NULL)
1042                                 goto more;
1043                         berr = filename__read_build_id(name, build_id,
1044                                                        BUILD_ID_SIZE);
1045 compare_build_id:
1046                         match = berr > 0 && memcmp(build_id, self->build_id,
1047                                                    sizeof(self->build_id)) == 0;
1048                         free(build_id);
1049                         build_id = NULL;
1050                         if (!match)
1051                                 goto more;
1052                 }
1053
1054                 fd = open(name, O_RDONLY);
1055         } while (fd < 0);
1056
1057         ret = dso__load_sym(self, map, name, fd, filter, 0, 0);
1058         close(fd);
1059
1060         /*
1061          * Some people seem to have debuginfo files _WITHOUT_ debug info!?!?
1062          */
1063         if (!ret)
1064                 goto more;
1065
1066         if (ret > 0) {
1067                 int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
1068                 if (nr_plt > 0)
1069                         ret += nr_plt;
1070         }
1071 out:
1072         free(name);
1073         if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
1074                 return 0;
1075         return ret;
1076 }
1077
1078 struct map *kernel_map;
1079
1080 static void kernel_maps__insert(struct map *map)
1081 {
1082         maps__insert(&kernel_maps, map);
1083 }
1084
1085 struct symbol *kernel_maps__find_symbol(u64 ip, struct map **mapp)
1086 {
1087         struct map *map = maps__find(&kernel_maps, ip);
1088
1089         if (mapp)
1090                 *mapp = map;
1091
1092         if (map) {
1093                 ip = map->map_ip(map, ip);
1094                 return map->dso->find_symbol(map->dso, ip);
1095         }
1096
1097         return NULL;
1098 }
1099
1100 struct map *kernel_maps__find_by_dso_name(const char *name)
1101 {
1102         struct rb_node *nd;
1103
1104         for (nd = rb_first(&kernel_maps); nd; nd = rb_next(nd)) {
1105                 struct map *map = rb_entry(nd, struct map, rb_node);
1106
1107                 if (map->dso && strcmp(map->dso->name, name) == 0)
1108                         return map;
1109         }
1110
1111         return NULL;
1112 }
1113
1114 static int dso__load_module_sym(struct dso *self, struct map *map,
1115                                 symbol_filter_t filter)
1116 {
1117         int err = 0, fd = open(self->long_name, O_RDONLY);
1118
1119         self->loaded = 1;
1120
1121         if (fd < 0) {
1122                 pr_err("%s: cannot open %s\n", __func__, self->long_name);
1123                 return err;
1124         }
1125
1126         err = dso__load_sym(self, map, self->long_name, fd, filter, 0, 1);
1127         close(fd);
1128
1129         return err;
1130 }
1131
1132 static int dsos__load_modules_sym_dir(char *dirname, symbol_filter_t filter)
1133 {
1134         struct dirent *dent;
1135         int nr_symbols = 0, err;
1136         DIR *dir = opendir(dirname);
1137
1138         if (!dir) {
1139                 pr_err("%s: cannot open %s dir\n", __func__, dirname);
1140                 return -1;
1141         }
1142
1143         while ((dent = readdir(dir)) != NULL) {
1144                 char path[PATH_MAX];
1145
1146                 if (dent->d_type == DT_DIR) {
1147                         if (!strcmp(dent->d_name, ".") ||
1148                             !strcmp(dent->d_name, ".."))
1149                                 continue;
1150
1151                         snprintf(path, sizeof(path), "%s/%s",
1152                                  dirname, dent->d_name);
1153                         err = dsos__load_modules_sym_dir(path, filter);
1154                         if (err < 0)
1155                                 goto failure;
1156                 } else {
1157                         char *dot = strrchr(dent->d_name, '.'),
1158                              dso_name[PATH_MAX];
1159                         struct map *map;
1160                         struct rb_node *last;
1161
1162                         if (dot == NULL || strcmp(dot, ".ko"))
1163                                 continue;
1164                         snprintf(dso_name, sizeof(dso_name), "[%.*s]",
1165                                  (int)(dot - dent->d_name), dent->d_name);
1166
1167                         strxfrchar(dso_name, '-', '_');
1168                         map = kernel_maps__find_by_dso_name(dso_name);
1169                         if (map == NULL)
1170                                 continue;
1171
1172                         snprintf(path, sizeof(path), "%s/%s",
1173                                  dirname, dent->d_name);
1174
1175                         map->dso->long_name = strdup(path);
1176                         if (map->dso->long_name == NULL)
1177                                 goto failure;
1178
1179                         err = dso__load_module_sym(map->dso, map, filter);
1180                         if (err < 0)
1181                                 goto failure;
1182                         last = rb_last(&map->dso->syms);
1183                         if (last) {
1184                                 struct symbol *sym;
1185                                 /*
1186                                  * We do this here as well, even having the
1187                                  * symbol size found in the symtab because
1188                                  * misannotated ASM symbols may have the size
1189                                  * set to zero.
1190                                  */
1191                                 dso__fixup_sym_end(map->dso);
1192
1193                                 sym = rb_entry(last, struct symbol, rb_node);
1194                                 map->end = map->start + sym->end;
1195                         }
1196                 }
1197                 nr_symbols += err;
1198         }
1199
1200         return nr_symbols;
1201 failure:
1202         closedir(dir);
1203         return -1;
1204 }
1205
1206 static int dsos__load_modules_sym(symbol_filter_t filter)
1207 {
1208         struct utsname uts;
1209         char modules_path[PATH_MAX];
1210
1211         if (uname(&uts) < 0)
1212                 return -1;
1213
1214         snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
1215                  uts.release);
1216
1217         return dsos__load_modules_sym_dir(modules_path, filter);
1218 }
1219
1220 /*
1221  * Constructor variant for modules (where we know from /proc/modules where
1222  * they are loaded) and for vmlinux, where only after we load all the
1223  * symbols we'll know where it starts and ends.
1224  */
1225 static struct map *map__new2(u64 start, struct dso *dso)
1226 {
1227         struct map *self = malloc(sizeof(*self));
1228
1229         if (self != NULL) {
1230                 /*
1231                  * ->end will be filled after we load all the symbols
1232                  */
1233                 map__init(self, start, 0, 0, dso);
1234         }
1235
1236         return self;
1237 }
1238
1239 static int dsos__load_modules(void)
1240 {
1241         char *line = NULL;
1242         size_t n;
1243         FILE *file = fopen("/proc/modules", "r");
1244         struct map *map;
1245
1246         if (file == NULL)
1247                 return -1;
1248
1249         while (!feof(file)) {
1250                 char name[PATH_MAX];
1251                 u64 start;
1252                 struct dso *dso;
1253                 char *sep;
1254                 int line_len;
1255
1256                 line_len = getline(&line, &n, file);
1257                 if (line_len < 0)
1258                         break;
1259
1260                 if (!line)
1261                         goto out_failure;
1262
1263                 line[--line_len] = '\0'; /* \n */
1264
1265                 sep = strrchr(line, 'x');
1266                 if (sep == NULL)
1267                         continue;
1268
1269                 hex2u64(sep + 1, &start);
1270
1271                 sep = strchr(line, ' ');
1272                 if (sep == NULL)
1273                         continue;
1274
1275                 *sep = '\0';
1276
1277                 snprintf(name, sizeof(name), "[%s]", line);
1278                 dso = dso__new(name);
1279
1280                 if (dso == NULL)
1281                         goto out_delete_line;
1282
1283                 map = map__new2(start, dso);
1284                 if (map == NULL) {
1285                         dso__delete(dso);
1286                         goto out_delete_line;
1287                 }
1288
1289                 dso->origin = DSO__ORIG_KMODULE;
1290                 kernel_maps__insert(map);
1291                 dsos__add(dso);
1292         }
1293
1294         free(line);
1295         fclose(file);
1296
1297         return 0;
1298
1299 out_delete_line:
1300         free(line);
1301 out_failure:
1302         return -1;
1303 }
1304
1305 static int dso__load_vmlinux(struct dso *self, struct map *map,
1306                              const char *vmlinux, symbol_filter_t filter)
1307 {
1308         int err, fd = open(vmlinux, O_RDONLY);
1309
1310         self->loaded = 1;
1311
1312         if (fd < 0)
1313                 return -1;
1314
1315         err = dso__load_sym(self, map, self->long_name, fd, filter, 1, 0);
1316
1317         close(fd);
1318
1319         return err;
1320 }
1321
1322 int dsos__load_kernel(const char *vmlinux, symbol_filter_t filter,
1323                       int use_modules)
1324 {
1325         int err = -1;
1326         struct dso *dso = dso__new(vmlinux);
1327
1328         if (dso == NULL)
1329                 return -1;
1330
1331         dso->short_name = "[kernel]";
1332         kernel_map = map__new2(0, dso);
1333         if (kernel_map == NULL)
1334                 goto out_delete_dso;
1335
1336         kernel_map->map_ip = kernel_map->unmap_ip = identity__map_ip;
1337
1338         if (use_modules && dsos__load_modules() < 0) {
1339                 pr_warning("Failed to load list of modules in use! "
1340                            "Continuing...\n");
1341                 use_modules = 0;
1342         }
1343
1344         if (vmlinux) {
1345                 err = dso__load_vmlinux(dso, kernel_map, vmlinux, filter);
1346                 if (err > 0 && use_modules) {
1347                         int syms = dsos__load_modules_sym(filter);
1348
1349                         if (syms < 0)
1350                                 pr_warning("Failed to read module symbols!"
1351                                            " Continuing...\n");
1352                         else
1353                                 err += syms;
1354                 }
1355         }
1356
1357         if (err <= 0)
1358                 err = kernel_maps__load_kallsyms(filter, use_modules);
1359
1360         if (err > 0) {
1361                 struct rb_node *node = rb_first(&dso->syms);
1362                 struct symbol *sym = rb_entry(node, struct symbol, rb_node);
1363
1364                 kernel_map->start = sym->start;
1365                 node = rb_last(&dso->syms);
1366                 sym = rb_entry(node, struct symbol, rb_node);
1367                 kernel_map->end = sym->end;
1368
1369                 dso->origin = DSO__ORIG_KERNEL;
1370                 kernel_maps__insert(kernel_map);
1371                 /*
1372                  * Now that we have all sorted out, just set the ->end of all
1373                  * maps:
1374                  */
1375                 kernel_maps__fixup_end();
1376                 dsos__add(dso);
1377
1378                 if (verbose)
1379                         kernel_maps__fprintf(stderr);
1380         }
1381
1382         return err;
1383
1384 out_delete_dso:
1385         dso__delete(dso);
1386         return -1;
1387 }
1388
1389 LIST_HEAD(dsos);
1390 struct dso      *vdso;
1391
1392 const char      *vmlinux_name = "vmlinux";
1393 int             modules;
1394
1395 static void dsos__add(struct dso *dso)
1396 {
1397         list_add_tail(&dso->node, &dsos);
1398 }
1399
1400 static struct dso *dsos__find(const char *name)
1401 {
1402         struct dso *pos;
1403
1404         list_for_each_entry(pos, &dsos, node)
1405                 if (strcmp(pos->name, name) == 0)
1406                         return pos;
1407         return NULL;
1408 }
1409
1410 struct dso *dsos__findnew(const char *name)
1411 {
1412         struct dso *dso = dsos__find(name);
1413
1414         if (!dso) {
1415                 dso = dso__new(name);
1416                 if (dso != NULL)
1417                         dsos__add(dso);
1418         }
1419
1420         return dso;
1421 }
1422
1423 void dsos__fprintf(FILE *fp)
1424 {
1425         struct dso *pos;
1426
1427         list_for_each_entry(pos, &dsos, node)
1428                 dso__fprintf(pos, fp);
1429 }
1430
1431 int load_kernel(symbol_filter_t filter)
1432 {
1433         if (dsos__load_kernel(vmlinux_name, filter, modules) <= 0)
1434                 return -1;
1435
1436         vdso = dso__new("[vdso]");
1437         if (!vdso)
1438                 return -1;
1439
1440         dsos__add(vdso);
1441
1442         return 0;
1443 }
1444
1445 void symbol__init(unsigned int priv_size)
1446 {
1447         elf_version(EV_CURRENT);
1448         symbol__priv_size = priv_size;
1449 }