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 <asm/bug.h>
  10 #include <libelf.h>
  11 #include <gelf.h>
  12 #include <elf.h>
  13 #include <limits.h>
  14 #include <sys/utsname.h>
  15
  16 #ifndef NT_GNU_BUILD_ID
  17 #define NT_GNU_BUILD_ID 3
  18 #endif
  19
  20 enum dso_origin {
  21         DSO__ORIG_KERNEL = 0,
  22         DSO__ORIG_JAVA_JIT,
  23         DSO__ORIG_FEDORA,
  24         DSO__ORIG_UBUNTU,
  25         DSO__ORIG_BUILDID,
  26         DSO__ORIG_DSO,
  27         DSO__ORIG_KMODULE,
  28         DSO__ORIG_NOT_FOUND,
  29 };
  30
  31 static void dsos__add(struct list_head *head, struct dso *dso);
  32 static struct map *thread__find_map_by_name(struct thread *self, char *name);
  33 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
  34 struct symbol *dso__find_symbol(struct dso *self, enum map_type type, u64 addr);
  35 static int dso__load_kernel_sym(struct dso *self, struct map *map,
  36                                 struct thread *thread, symbol_filter_t filter);
  37 unsigned int symbol__priv_size;
  38 static int vmlinux_path__nr_entries;
  39 static char **vmlinux_path;
  40
  41 static struct symbol_conf symbol_conf__defaults = {
  42         .use_modules      = true,
  43         .try_vmlinux_path = true,
  44 };
  45
  46 static struct thread kthread_mem, *kthread = &kthread_mem;
  47
  48 bool dso__loaded(const struct dso *self, enum map_type type)
  49 {
  50         return self->loaded & (1 << type);
  51 }
  52
  53 static void dso__set_loaded(struct dso *self, enum map_type type)
  54 {
  55         self->loaded |= (1 << type);
  56 }
  57
  58 static void symbols__fixup_end(struct rb_root *self)
  59 {
  60         struct rb_node *nd, *prevnd = rb_first(self);
  61         struct symbol *curr, *prev;
  62
  63         if (prevnd == NULL)
  64                 return;
  65
  66         curr = rb_entry(prevnd, struct symbol, rb_node);
  67
  68         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  69                 prev = curr;
  70                 curr = rb_entry(nd, struct symbol, rb_node);
  71
  72                 if (prev->end == prev->start)
  73                         prev->end = curr->start - 1;
  74         }
  75
  76         /* Last entry */
  77         if (curr->end == curr->start)
  78                 curr->end = roundup(curr->start, 4096);
  79 }
  80
  81 static void __thread__fixup_maps_end(struct thread *self, enum map_type type)
  82 {
  83         struct map *prev, *curr;
  84         struct rb_node *nd, *prevnd = rb_first(&self->maps[type]);
  85
  86         if (prevnd == NULL)
  87                 return;
  88
  89         curr = rb_entry(prevnd, struct map, rb_node);
  90
  91         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
  92                 prev = curr;
  93                 curr = rb_entry(nd, struct map, rb_node);
  94                 prev->end = curr->start - 1;
  95         }
  96
  97         /*
  98          * We still haven't the actual symbols, so guess the
  99          * last map final address.
 100          */
 101         curr->end = ~0UL;
 102 }
 103
 104 static void thread__fixup_maps_end(struct thread *self)
 105 {
 106         int i;
 107         for (i = 0; i < MAP__NR_TYPES; ++i)
 108                 __thread__fixup_maps_end(self, i);
 109 }
 110
 111 static struct symbol *symbol__new(u64 start, u64 len, const char *name)
 112 {
 113         size_t namelen = strlen(name) + 1;
 114         struct symbol *self = zalloc(symbol__priv_size +
 115                                      sizeof(*self) + namelen);
 116         if (self == NULL)
 117                 return NULL;
 118
 119         if (symbol__priv_size)
 120                 self = ((void *)self) + symbol__priv_size;
 121
 122         self->start = start;
 123         self->end   = len ? start + len - 1 : start;
 124
 125         pr_debug3("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
 126
 127         memcpy(self->name, name, namelen);
 128
 129         return self;
 130 }
 131
 132 static void symbol__delete(struct symbol *self)
 133 {
 134         free(((void *)self) - symbol__priv_size);
 135 }
 136
 137 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
 138 {
 139         return fprintf(fp, " %llx-%llx %s\n",
 140                        self->start, self->end, self->name);
 141 }
 142
 143 static void dso__set_long_name(struct dso *self, char *name)
 144 {
 145         if (name == NULL)
 146                 return;
 147         self->long_name = name;
 148         self->long_name_len = strlen(name);
 149 }
 150
 151 static void dso__set_basename(struct dso *self)
 152 {
 153         self->short_name = basename(self->long_name);
 154 }
 155
 156 struct dso *dso__new(const char *name)
 157 {
 158         struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
 159
 160         if (self != NULL) {
 161                 int i;
 162                 strcpy(self->name, name);
 163                 dso__set_long_name(self, self->name);
 164                 self->short_name = self->name;
 165                 for (i = 0; i < MAP__NR_TYPES; ++i)
 166                         self->symbols[i] = RB_ROOT;
 167                 self->find_symbol = dso__find_symbol;
 168                 self->slen_calculated = 0;
 169                 self->origin = DSO__ORIG_NOT_FOUND;
 170                 self->loaded = 0;
 171                 self->has_build_id = 0;
 172         }
 173
 174         return self;
 175 }
 176
 177 static void symbols__delete(struct rb_root *self)
 178 {
 179         struct symbol *pos;
 180         struct rb_node *next = rb_first(self);
 181
 182         while (next) {
 183                 pos = rb_entry(next, struct symbol, rb_node);
 184                 next = rb_next(&pos->rb_node);
 185                 rb_erase(&pos->rb_node, self);
 186                 symbol__delete(pos);
 187         }
 188 }
 189
 190 void dso__delete(struct dso *self)
 191 {
 192         int i;
 193         for (i = 0; i < MAP__NR_TYPES; ++i)
 194                 symbols__delete(&self->symbols[i]);
 195         if (self->long_name != self->name)
 196                 free(self->long_name);
 197         free(self);
 198 }
 199
 200 void dso__set_build_id(struct dso *self, void *build_id)
 201 {
 202         memcpy(self->build_id, build_id, sizeof(self->build_id));
 203         self->has_build_id = 1;
 204 }
 205
 206 static void symbols__insert(struct rb_root *self, struct symbol *sym)
 207 {
 208         struct rb_node **p = &self->rb_node;
 209         struct rb_node *parent = NULL;
 210         const u64 ip = sym->start;
 211         struct symbol *s;
 212
 213         while (*p != NULL) {
 214                 parent = *p;
 215                 s = rb_entry(parent, struct symbol, rb_node);
 216                 if (ip < s->start)
 217                         p = &(*p)->rb_left;
 218                 else
 219                         p = &(*p)->rb_right;
 220         }
 221         rb_link_node(&sym->rb_node, parent, p);
 222         rb_insert_color(&sym->rb_node, self);
 223 }
 224
 225 static struct symbol *symbols__find(struct rb_root *self, u64 ip)
 226 {
 227         struct rb_node *n;
 228
 229         if (self == NULL)
 230                 return NULL;
 231
 232         n = self->rb_node;
 233
 234         while (n) {
 235                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 236
 237                 if (ip < s->start)
 238                         n = n->rb_left;
 239                 else if (ip > s->end)
 240                         n = n->rb_right;
 241                 else
 242                         return s;
 243         }
 244
 245         return NULL;
 246 }
 247
 248 struct symbol *dso__find_symbol(struct dso *self, enum map_type type, u64 addr)
 249 {
 250         return symbols__find(&self->symbols[type], addr);
 251 }
 252
 253 int build_id__sprintf(u8 *self, int len, char *bf)
 254 {
 255         char *bid = bf;
 256         u8 *raw = self;
 257         int i;
 258
 259         for (i = 0; i < len; ++i) {
 260                 sprintf(bid, "%02x", *raw);
 261                 ++raw;
 262                 bid += 2;
 263         }
 264
 265         return raw - self;
 266 }
 267
 268 size_t dso__fprintf_buildid(struct dso *self, FILE *fp)
 269 {
 270         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
 271
 272         build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
 273         return fprintf(fp, "%s", sbuild_id);
 274 }
 275
 276 size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
 277 {
 278         struct rb_node *nd;
 279         size_t ret = fprintf(fp, "dso: %s (", self->short_name);
 280
 281         ret += dso__fprintf_buildid(self, fp);
 282         ret += fprintf(fp, ")\n");
 283         for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
 284                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 285                 ret += symbol__fprintf(pos, fp);
 286         }
 287
 288         return ret;
 289 }
 290
 291 /*
 292  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 293  * so that we can in the next step set the symbol ->end address and then
 294  * call kernel_maps__split_kallsyms.
 295  */
 296 static int dso__load_all_kallsyms(struct dso *self, struct map *map)
 297 {
 298         char *line = NULL;
 299         size_t n;
 300         struct rb_root *root = &self->symbols[map->type];
 301         FILE *file = fopen("/proc/kallsyms", "r");
 302
 303         if (file == NULL)
 304                 goto out_failure;
 305
 306         while (!feof(file)) {
 307                 u64 start;
 308                 struct symbol *sym;
 309                 int line_len, len;
 310                 char symbol_type;
 311                 char *symbol_name;
 312
 313                 line_len = getline(&line, &n, file);
 314                 if (line_len < 0)
 315                         break;
 316
 317                 if (!line)
 318                         goto out_failure;
 319
 320                 line[--line_len] = '\0'; /* \n */
 321
 322                 len = hex2u64(line, &start);
 323
 324                 len++;
 325                 if (len + 2 >= line_len)
 326                         continue;
 327
 328                 symbol_type = toupper(line[len]);
 329                 /*
 330                  * We're interested only in code ('T'ext)
 331                  */
 332                 if (symbol_type != 'T' && symbol_type != 'W')
 333                         continue;
 334
 335                 symbol_name = line + len + 2;
 336                 /*
 337                  * Will fix up the end later, when we have all symbols sorted.
 338                  */
 339                 sym = symbol__new(start, 0, symbol_name);
 340
 341                 if (sym == NULL)
 342                         goto out_delete_line;
 343                 /*
 344                  * We will pass the symbols to the filter later, in
 345                  * map__split_kallsyms, when we have split the maps per module
 346                  */
 347                 symbols__insert(root, sym);
 348         }
 349
 350         free(line);
 351         fclose(file);
 352
 353         return 0;
 354
 355 out_delete_line:
 356         free(line);
 357 out_failure:
 358         return -1;
 359 }
 360
 361 /*
 362  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 363  * kernel range is broken in several maps, named [kernel].N, as we don't have
 364  * the original ELF section names vmlinux have.
 365  */
 366 static int dso__split_kallsyms(struct dso *self, struct map *map, struct thread *thread,
 367                                symbol_filter_t filter)
 368 {
 369         struct map *curr_map = map;
 370         struct symbol *pos;
 371         int count = 0;
 372         struct rb_root *root = &self->symbols[map->type];
 373         struct rb_node *next = rb_first(root);
 374         int kernel_range = 0;
 375
 376         while (next) {
 377                 char *module;
 378
 379                 pos = rb_entry(next, struct symbol, rb_node);
 380                 next = rb_next(&pos->rb_node);
 381
 382                 module = strchr(pos->name, '\t');
 383                 if (module) {
 384                         if (!thread->use_modules)
 385                                 goto discard_symbol;
 386
 387                         *module++ = '\0';
 388
 389                         if (strcmp(self->name, module)) {
 390                                 curr_map = thread__find_map_by_name(thread, module);
 391                                 if (curr_map == NULL) {
 392                                         pr_debug("/proc/{kallsyms,modules} "
 393                                                  "inconsistency!\n");
 394                                         return -1;
 395                                 }
 396                         }
 397                         /*
 398                          * So that we look just like we get from .ko files,
 399                          * i.e. not prelinked, relative to map->start.
 400                          */
 401                         pos->start = curr_map->map_ip(curr_map, pos->start);
 402                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 403                 } else if (curr_map != map) {
 404                         char dso_name[PATH_MAX];
 405                         struct dso *dso;
 406
 407                         snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
 408                                  kernel_range++);
 409
 410                         dso = dso__new(dso_name);
 411                         if (dso == NULL)
 412                                 return -1;
 413
 414                         curr_map = map__new2(pos->start, dso, map->type);
 415                         if (map == NULL) {
 416                                 dso__delete(dso);
 417                                 return -1;
 418                         }
 419
 420                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 421                         __thread__insert_map(thread, curr_map);
 422                         ++kernel_range;
 423                 }
 424
 425                 if (filter && filter(curr_map, pos)) {
 426 discard_symbol:         rb_erase(&pos->rb_node, root);
 427                         symbol__delete(pos);
 428                 } else {
 429                         if (curr_map != map) {
 430                                 rb_erase(&pos->rb_node, root);
 431                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 432                         }
 433                         count++;
 434                 }
 435         }
 436
 437         return count;
 438 }
 439
 440
 441 static int dso__load_kallsyms(struct dso *self, struct map *map,
 442                               struct thread *thread, symbol_filter_t filter)
 443 {
 444         if (dso__load_all_kallsyms(self, map) < 0)
 445                 return -1;
 446
 447         symbols__fixup_end(&self->symbols[map->type]);
 448         self->origin = DSO__ORIG_KERNEL;
 449
 450         return dso__split_kallsyms(self, map, thread, filter);
 451 }
 452
 453 size_t kernel_maps__fprintf(FILE *fp)
 454 {
 455         size_t printed = fprintf(fp, "Kernel maps:\n");
 456         printed += thread__fprintf_maps(kthread, fp);
 457         return printed + fprintf(fp, "END kernel maps\n");
 458 }
 459
 460 static int dso__load_perf_map(struct dso *self, struct map *map,
 461                               symbol_filter_t filter)
 462 {
 463         char *line = NULL;
 464         size_t n;
 465         FILE *file;
 466         int nr_syms = 0;
 467
 468         file = fopen(self->long_name, "r");
 469         if (file == NULL)
 470                 goto out_failure;
 471
 472         while (!feof(file)) {
 473                 u64 start, size;
 474                 struct symbol *sym;
 475                 int line_len, len;
 476
 477                 line_len = getline(&line, &n, file);
 478                 if (line_len < 0)
 479                         break;
 480
 481                 if (!line)
 482                         goto out_failure;
 483
 484                 line[--line_len] = '\0'; /* \n */
 485
 486                 len = hex2u64(line, &start);
 487
 488                 len++;
 489                 if (len + 2 >= line_len)
 490                         continue;
 491
 492                 len += hex2u64(line + len, &size);
 493
 494                 len++;
 495                 if (len + 2 >= line_len)
 496                         continue;
 497
 498                 sym = symbol__new(start, size, line + len);
 499
 500                 if (sym == NULL)
 501                         goto out_delete_line;
 502
 503                 if (filter && filter(map, sym))
 504                         symbol__delete(sym);
 505                 else {
 506                         symbols__insert(&self->symbols[map->type], sym);
 507                         nr_syms++;
 508                 }
 509         }
 510
 511         free(line);
 512         fclose(file);
 513
 514         return nr_syms;
 515
 516 out_delete_line:
 517         free(line);
 518 out_failure:
 519         return -1;
 520 }
 521
 522 /**
 523  * elf_symtab__for_each_symbol - iterate thru all the symbols
 524  *
 525  * @self: struct elf_symtab instance to iterate
 526  * @idx: uint32_t idx
 527  * @sym: GElf_Sym iterator
 528  */
 529 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
 530         for (idx = 0, gelf_getsym(syms, idx, &sym);\
 531              idx < nr_syms; \
 532              idx++, gelf_getsym(syms, idx, &sym))
 533
 534 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
 535 {
 536         return GELF_ST_TYPE(sym->st_info);
 537 }
 538
 539 static inline int elf_sym__is_function(const GElf_Sym *sym)
 540 {
 541         return elf_sym__type(sym) == STT_FUNC &&
 542                sym->st_name != 0 &&
 543                sym->st_shndx != SHN_UNDEF;
 544 }
 545
 546 static inline int elf_sym__is_label(const GElf_Sym *sym)
 547 {
 548         return elf_sym__type(sym) == STT_NOTYPE &&
 549                 sym->st_name != 0 &&
 550                 sym->st_shndx != SHN_UNDEF &&
 551                 sym->st_shndx != SHN_ABS;
 552 }
 553
 554 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
 555                                         const Elf_Data *secstrs)
 556 {
 557         return secstrs->d_buf + shdr->sh_name;
 558 }
 559
 560 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
 561                                         const Elf_Data *secstrs)
 562 {
 563         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
 564 }
 565
 566 static inline const char *elf_sym__name(const GElf_Sym *sym,
 567                                         const Elf_Data *symstrs)
 568 {
 569         return symstrs->d_buf + sym->st_name;
 570 }
 571
 572 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 573                                     GElf_Shdr *shp, const char *name,
 574                                     size_t *idx)
 575 {
 576         Elf_Scn *sec = NULL;
 577         size_t cnt = 1;
 578
 579         while ((sec = elf_nextscn(elf, sec)) != NULL) {
 580                 char *str;
 581
 582                 gelf_getshdr(sec, shp);
 583                 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
 584                 if (!strcmp(name, str)) {
 585                         if (idx)
 586                                 *idx = cnt;
 587                         break;
 588                 }
 589                 ++cnt;
 590         }
 591
 592         return sec;
 593 }
 594
 595 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
 596         for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
 597              idx < nr_entries; \
 598              ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
 599
 600 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
 601         for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
 602              idx < nr_entries; \
 603              ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
 604
 605 /*
 606  * We need to check if we have a .dynsym, so that we can handle the
 607  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
 608  * .dynsym or .symtab).
 609  * And always look at the original dso, not at debuginfo packages, that
 610  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
 611  */
 612 static int dso__synthesize_plt_symbols(struct  dso *self, struct map *map,
 613                                        symbol_filter_t filter)
 614 {
 615         uint32_t nr_rel_entries, idx;
 616         GElf_Sym sym;
 617         u64 plt_offset;
 618         GElf_Shdr shdr_plt;
 619         struct symbol *f;
 620         GElf_Shdr shdr_rel_plt, shdr_dynsym;
 621         Elf_Data *reldata, *syms, *symstrs;
 622         Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
 623         size_t dynsym_idx;
 624         GElf_Ehdr ehdr;
 625         char sympltname[1024];
 626         Elf *elf;
 627         int nr = 0, symidx, fd, err = 0;
 628
 629         fd = open(self->long_name, O_RDONLY);
 630         if (fd < 0)
 631                 goto out;
 632
 633         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 634         if (elf == NULL)
 635                 goto out_close;
 636
 637         if (gelf_getehdr(elf, &ehdr) == NULL)
 638                 goto out_elf_end;
 639
 640         scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
 641                                          ".dynsym", &dynsym_idx);
 642         if (scn_dynsym == NULL)
 643                 goto out_elf_end;
 644
 645         scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 646                                           ".rela.plt", NULL);
 647         if (scn_plt_rel == NULL) {
 648                 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 649                                                   ".rel.plt", NULL);
 650                 if (scn_plt_rel == NULL)
 651                         goto out_elf_end;
 652         }
 653
 654         err = -1;
 655
 656         if (shdr_rel_plt.sh_link != dynsym_idx)
 657                 goto out_elf_end;
 658
 659         if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
 660                 goto out_elf_end;
 661
 662         /*
 663          * Fetch the relocation section to find the idxes to the GOT
 664          * and the symbols in the .dynsym they refer to.
 665          */
 666         reldata = elf_getdata(scn_plt_rel, NULL);
 667         if (reldata == NULL)
 668                 goto out_elf_end;
 669
 670         syms = elf_getdata(scn_dynsym, NULL);
 671         if (syms == NULL)
 672                 goto out_elf_end;
 673
 674         scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
 675         if (scn_symstrs == NULL)
 676                 goto out_elf_end;
 677
 678         symstrs = elf_getdata(scn_symstrs, NULL);
 679         if (symstrs == NULL)
 680                 goto out_elf_end;
 681
 682         nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
 683         plt_offset = shdr_plt.sh_offset;
 684
 685         if (shdr_rel_plt.sh_type == SHT_RELA) {
 686                 GElf_Rela pos_mem, *pos;
 687
 688                 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
 689                                            nr_rel_entries) {
 690                         symidx = GELF_R_SYM(pos->r_info);
 691                         plt_offset += shdr_plt.sh_entsize;
 692                         gelf_getsym(syms, symidx, &sym);
 693                         snprintf(sympltname, sizeof(sympltname),
 694                                  "%s@plt", elf_sym__name(&sym, symstrs));
 695
 696                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 697                                         sympltname);
 698                         if (!f)
 699                                 goto out_elf_end;
 700
 701                         if (filter && filter(map, f))
 702                                 symbol__delete(f);
 703                         else {
 704                                 symbols__insert(&self->symbols[map->type], f);
 705                                 ++nr;
 706                         }
 707                 }
 708         } else if (shdr_rel_plt.sh_type == SHT_REL) {
 709                 GElf_Rel pos_mem, *pos;
 710                 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
 711                                           nr_rel_entries) {
 712                         symidx = GELF_R_SYM(pos->r_info);
 713                         plt_offset += shdr_plt.sh_entsize;
 714                         gelf_getsym(syms, symidx, &sym);
 715                         snprintf(sympltname, sizeof(sympltname),
 716                                  "%s@plt", elf_sym__name(&sym, symstrs));
 717
 718                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 719                                         sympltname);
 720                         if (!f)
 721                                 goto out_elf_end;
 722
 723                         if (filter && filter(map, f))
 724                                 symbol__delete(f);
 725                         else {
 726                                 symbols__insert(&self->symbols[map->type], f);
 727                                 ++nr;
 728                         }
 729                 }
 730         }
 731
 732         err = 0;
 733 out_elf_end:
 734         elf_end(elf);
 735 out_close:
 736         close(fd);
 737
 738         if (err == 0)
 739                 return nr;
 740 out:
 741         pr_warning("%s: problems reading %s PLT info.\n",
 742                    __func__, self->long_name);
 743         return 0;
 744 }
 745
 746 static int dso__load_sym(struct dso *self, struct map *map,
 747                          struct thread *thread, const char *name, int fd,
 748                          symbol_filter_t filter, int kernel, int kmodule)
 749 {
 750         struct map *curr_map = map;
 751         struct dso *curr_dso = self;
 752         size_t dso_name_len = strlen(self->short_name);
 753         Elf_Data *symstrs, *secstrs;
 754         uint32_t nr_syms;
 755         int err = -1;
 756         uint32_t idx;
 757         GElf_Ehdr ehdr;
 758         GElf_Shdr shdr;
 759         Elf_Data *syms;
 760         GElf_Sym sym;
 761         Elf_Scn *sec, *sec_strndx;
 762         Elf *elf;
 763         int nr = 0;
 764
 765         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 766         if (elf == NULL) {
 767                 pr_err("%s: cannot read %s ELF file.\n", __func__, name);
 768                 goto out_close;
 769         }
 770
 771         if (gelf_getehdr(elf, &ehdr) == NULL) {
 772                 pr_err("%s: cannot get elf header.\n", __func__);
 773                 goto out_elf_end;
 774         }
 775
 776         sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
 777         if (sec == NULL) {
 778                 sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
 779                 if (sec == NULL)
 780                         goto out_elf_end;
 781         }
 782
 783         syms = elf_getdata(sec, NULL);
 784         if (syms == NULL)
 785                 goto out_elf_end;
 786
 787         sec = elf_getscn(elf, shdr.sh_link);
 788         if (sec == NULL)
 789                 goto out_elf_end;
 790
 791         symstrs = elf_getdata(sec, NULL);
 792         if (symstrs == NULL)
 793                 goto out_elf_end;
 794
 795         sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
 796         if (sec_strndx == NULL)
 797                 goto out_elf_end;
 798
 799         secstrs = elf_getdata(sec_strndx, NULL);
 800         if (secstrs == NULL)
 801                 goto out_elf_end;
 802
 803         nr_syms = shdr.sh_size / shdr.sh_entsize;
 804
 805         memset(&sym, 0, sizeof(sym));
 806         if (!kernel) {
 807                 self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
 808                                 elf_section_by_name(elf, &ehdr, &shdr,
 809                                                      ".gnu.prelink_undo",
 810                                                      NULL) != NULL);
 811         } else self->adjust_symbols = 0;
 812
 813         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
 814                 struct symbol *f;
 815                 const char *elf_name;
 816                 char *demangled = NULL;
 817                 int is_label = elf_sym__is_label(&sym);
 818                 const char *section_name;
 819
 820                 if (!is_label && !elf_sym__is_function(&sym))
 821                         continue;
 822
 823                 sec = elf_getscn(elf, sym.st_shndx);
 824                 if (!sec)
 825                         goto out_elf_end;
 826
 827                 gelf_getshdr(sec, &shdr);
 828
 829                 if (is_label && !elf_sec__is_text(&shdr, secstrs))
 830                         continue;
 831
 832                 elf_name = elf_sym__name(&sym, symstrs);
 833                 section_name = elf_sec__name(&shdr, secstrs);
 834
 835                 if (kernel || kmodule) {
 836                         char dso_name[PATH_MAX];
 837
 838                         if (strcmp(section_name,
 839                                    curr_dso->short_name + dso_name_len) == 0)
 840                                 goto new_symbol;
 841
 842                         if (strcmp(section_name, ".text") == 0) {
 843                                 curr_map = map;
 844                                 curr_dso = self;
 845                                 goto new_symbol;
 846                         }
 847
 848                         snprintf(dso_name, sizeof(dso_name),
 849                                  "%s%s", self->short_name, section_name);
 850
 851                         curr_map = thread__find_map_by_name(thread, dso_name);
 852                         if (curr_map == NULL) {
 853                                 u64 start = sym.st_value;
 854
 855                                 if (kmodule)
 856                                         start += map->start + shdr.sh_offset;
 857
 858                                 curr_dso = dso__new(dso_name);
 859                                 if (curr_dso == NULL)
 860                                         goto out_elf_end;
 861                                 curr_map = map__new2(start, curr_dso,
 862                                                      MAP__FUNCTION);
 863                                 if (curr_map == NULL) {
 864                                         dso__delete(curr_dso);
 865                                         goto out_elf_end;
 866                                 }
 867                                 curr_map->map_ip = identity__map_ip;
 868                                 curr_map->unmap_ip = identity__map_ip;
 869                                 curr_dso->origin = DSO__ORIG_KERNEL;
 870                                 __thread__insert_map(kthread, curr_map);
 871                                 dsos__add(&dsos__kernel, curr_dso);
 872                         } else
 873                                 curr_dso = curr_map->dso;
 874
 875                         goto new_symbol;
 876                 }
 877
 878                 if (curr_dso->adjust_symbols) {
 879                         pr_debug2("adjusting symbol: st_value: %Lx sh_addr: "
 880                                   "%Lx sh_offset: %Lx\n", (u64)sym.st_value,
 881                                   (u64)shdr.sh_addr, (u64)shdr.sh_offset);
 882                         sym.st_value -= shdr.sh_addr - shdr.sh_offset;
 883                 }
 884                 /*
 885                  * We need to figure out if the object was created from C++ sources
 886                  * DWARF DW_compile_unit has this, but we don't always have access
 887                  * to it...
 888                  */
 889                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
 890                 if (demangled != NULL)
 891                         elf_name = demangled;
 892 new_symbol:
 893                 f = symbol__new(sym.st_value, sym.st_size, elf_name);
 894                 free(demangled);
 895                 if (!f)
 896                         goto out_elf_end;
 897
 898                 if (filter && filter(curr_map, f))
 899                         symbol__delete(f);
 900                 else {
 901                         symbols__insert(&curr_dso->symbols[curr_map->type], f);
 902                         nr++;
 903                 }
 904         }
 905
 906         /*
 907          * For misannotated, zeroed, ASM function sizes.
 908          */
 909         if (nr > 0)
 910                 symbols__fixup_end(&self->symbols[map->type]);
 911         err = nr;
 912 out_elf_end:
 913         elf_end(elf);
 914 out_close:
 915         return err;
 916 }
 917
 918 static bool dso__build_id_equal(const struct dso *self, u8 *build_id)
 919 {
 920         return memcmp(self->build_id, build_id, sizeof(self->build_id)) == 0;
 921 }
 922
 923 static bool __dsos__read_build_ids(struct list_head *head)
 924 {
 925         bool have_build_id = false;
 926         struct dso *pos;
 927
 928         list_for_each_entry(pos, head, node)
 929                 if (filename__read_build_id(pos->long_name, pos->build_id,
 930                                             sizeof(pos->build_id)) > 0) {
 931                         have_build_id     = true;
 932                         pos->has_build_id = true;
 933                 }
 934
 935         return have_build_id;
 936 }
 937
 938 bool dsos__read_build_ids(void)
 939 {
 940         return __dsos__read_build_ids(&dsos__kernel) ||
 941                __dsos__read_build_ids(&dsos__user);
 942 }
 943
 944 /*
 945  * Align offset to 4 bytes as needed for note name and descriptor data.
 946  */
 947 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
 948
 949 int filename__read_build_id(const char *filename, void *bf, size_t size)
 950 {
 951         int fd, err = -1;
 952         GElf_Ehdr ehdr;
 953         GElf_Shdr shdr;
 954         Elf_Data *data;
 955         Elf_Scn *sec;
 956         Elf_Kind ek;
 957         void *ptr;
 958         Elf *elf;
 959
 960         if (size < BUILD_ID_SIZE)
 961                 goto out;
 962
 963         fd = open(filename, O_RDONLY);
 964         if (fd < 0)
 965                 goto out;
 966
 967         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
 968         if (elf == NULL) {
 969                 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
 970                 goto out_close;
 971         }
 972
 973         ek = elf_kind(elf);
 974         if (ek != ELF_K_ELF)
 975                 goto out_elf_end;
 976
 977         if (gelf_getehdr(elf, &ehdr) == NULL) {
 978                 pr_err("%s: cannot get elf header.\n", __func__);
 979                 goto out_elf_end;
 980         }
 981
 982         sec = elf_section_by_name(elf, &ehdr, &shdr,
 983                                   ".note.gnu.build-id", NULL);
 984         if (sec == NULL) {
 985                 sec = elf_section_by_name(elf, &ehdr, &shdr,
 986                                           ".notes", NULL);
 987                 if (sec == NULL)
 988                         goto out_elf_end;
 989         }
 990
 991         data = elf_getdata(sec, NULL);
 992         if (data == NULL)
 993                 goto out_elf_end;
 994
 995         ptr = data->d_buf;
 996         while (ptr < (data->d_buf + data->d_size)) {
 997                 GElf_Nhdr *nhdr = ptr;
 998                 int namesz = NOTE_ALIGN(nhdr->n_namesz),
 999                     descsz = NOTE_ALIGN(nhdr->n_descsz);
1000                 const char *name;
1001
1002                 ptr += sizeof(*nhdr);
1003                 name = ptr;
1004                 ptr += namesz;
1005                 if (nhdr->n_type == NT_GNU_BUILD_ID &&
1006                     nhdr->n_namesz == sizeof("GNU")) {
1007                         if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
1008                                 memcpy(bf, ptr, BUILD_ID_SIZE);
1009                                 err = BUILD_ID_SIZE;
1010                                 break;
1011                         }
1012                 }
1013                 ptr += descsz;
1014         }
1015 out_elf_end:
1016         elf_end(elf);
1017 out_close:
1018         close(fd);
1019 out:
1020         return err;
1021 }
1022
1023 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
1024 {
1025         int fd, err = -1;
1026
1027         if (size < BUILD_ID_SIZE)
1028                 goto out;
1029
1030         fd = open(filename, O_RDONLY);
1031         if (fd < 0)
1032                 goto out;
1033
1034         while (1) {
1035                 char bf[BUFSIZ];
1036                 GElf_Nhdr nhdr;
1037                 int namesz, descsz;
1038
1039                 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
1040                         break;
1041
1042                 namesz = NOTE_ALIGN(nhdr.n_namesz);
1043                 descsz = NOTE_ALIGN(nhdr.n_descsz);
1044                 if (nhdr.n_type == NT_GNU_BUILD_ID &&
1045                     nhdr.n_namesz == sizeof("GNU")) {
1046                         if (read(fd, bf, namesz) != namesz)
1047                                 break;
1048                         if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
1049                                 if (read(fd, build_id,
1050                                     BUILD_ID_SIZE) == BUILD_ID_SIZE) {
1051                                         err = 0;
1052                                         break;
1053                                 }
1054                         } else if (read(fd, bf, descsz) != descsz)
1055                                 break;
1056                 } else {
1057                         int n = namesz + descsz;
1058                         if (read(fd, bf, n) != n)
1059                                 break;
1060                 }
1061         }
1062         close(fd);
1063 out:
1064         return err;
1065 }
1066
1067 char dso__symtab_origin(const struct dso *self)
1068 {
1069         static const char origin[] = {
1070                 [DSO__ORIG_KERNEL] =   'k',
1071                 [DSO__ORIG_JAVA_JIT] = 'j',
1072                 [DSO__ORIG_FEDORA] =   'f',
1073                 [DSO__ORIG_UBUNTU] =   'u',
1074                 [DSO__ORIG_BUILDID] =  'b',
1075                 [DSO__ORIG_DSO] =      'd',
1076                 [DSO__ORIG_KMODULE] =  'K',
1077         };
1078
1079         if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
1080                 return '!';
1081         return origin[self->origin];
1082 }
1083
1084 int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
1085 {
1086         int size = PATH_MAX;
1087         char *name;
1088         u8 build_id[BUILD_ID_SIZE];
1089         int ret = -1;
1090         int fd;
1091
1092         dso__set_loaded(self, map->type);
1093
1094         if (self->kernel)
1095                 return dso__load_kernel_sym(self, map, kthread, filter);
1096
1097         name = malloc(size);
1098         if (!name)
1099                 return -1;
1100
1101         self->adjust_symbols = 0;
1102
1103         if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
1104                 ret = dso__load_perf_map(self, map, filter);
1105                 self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
1106                                          DSO__ORIG_NOT_FOUND;
1107                 return ret;
1108         }
1109
1110         self->origin = DSO__ORIG_FEDORA - 1;
1111
1112 more:
1113         do {
1114                 self->origin++;
1115                 switch (self->origin) {
1116                 case DSO__ORIG_FEDORA:
1117                         snprintf(name, size, "/usr/lib/debug%s.debug",
1118                                  self->long_name);
1119                         break;
1120                 case DSO__ORIG_UBUNTU:
1121                         snprintf(name, size, "/usr/lib/debug%s",
1122                                  self->long_name);
1123                         break;
1124                 case DSO__ORIG_BUILDID:
1125                         if (filename__read_build_id(self->long_name, build_id,
1126                                                     sizeof(build_id))) {
1127                                 char build_id_hex[BUILD_ID_SIZE * 2 + 1];
1128
1129                                 build_id__sprintf(build_id, sizeof(build_id),
1130                                                   build_id_hex);
1131                                 snprintf(name, size,
1132                                          "/usr/lib/debug/.build-id/%.2s/%s.debug",
1133                                         build_id_hex, build_id_hex + 2);
1134                                 if (self->has_build_id)
1135                                         goto compare_build_id;
1136                                 break;
1137                         }
1138                         self->origin++;
1139                         /* Fall thru */
1140                 case DSO__ORIG_DSO:
1141                         snprintf(name, size, "%s", self->long_name);
1142                         break;
1143
1144                 default:
1145                         goto out;
1146                 }
1147
1148                 if (self->has_build_id) {
1149                         if (filename__read_build_id(name, build_id,
1150                                                     sizeof(build_id)) < 0)
1151                                 goto more;
1152 compare_build_id:
1153                         if (!dso__build_id_equal(self, build_id))
1154                                 goto more;
1155                 }
1156
1157                 fd = open(name, O_RDONLY);
1158         } while (fd < 0);
1159
1160         ret = dso__load_sym(self, map, NULL, name, fd, filter, 0, 0);
1161         close(fd);
1162
1163         /*
1164          * Some people seem to have debuginfo files _WITHOUT_ debug info!?!?
1165          */
1166         if (!ret)
1167                 goto more;
1168
1169         if (ret > 0) {
1170                 int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
1171                 if (nr_plt > 0)
1172                         ret += nr_plt;
1173         }
1174 out:
1175         free(name);
1176         if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
1177                 return 0;
1178         return ret;
1179 }
1180
1181 static struct symbol *thread__find_symbol(struct thread *self, u64 ip,
1182                                           enum map_type type, struct map **mapp,
1183                                           symbol_filter_t filter)
1184 {
1185         struct map *map = thread__find_map(self, type, ip);
1186
1187         if (mapp)
1188                 *mapp = map;
1189
1190         if (map) {
1191                 ip = map->map_ip(map, ip);
1192                 return map__find_symbol(map, ip, filter);
1193         }
1194
1195         return NULL;
1196 }
1197
1198 struct symbol *kernel_maps__find_function(u64 ip, struct map **mapp,
1199                                           symbol_filter_t filter)
1200 {
1201         return thread__find_symbol(kthread, ip, MAP__FUNCTION, mapp, filter);
1202 }
1203
1204 static struct map *thread__find_map_by_name(struct thread *self, char *name)
1205 {
1206         struct rb_node *nd;
1207
1208         for (nd = rb_first(&self->maps[MAP__FUNCTION]); nd; nd = rb_next(nd)) {
1209                 struct map *map = rb_entry(nd, struct map, rb_node);
1210
1211                 if (map->dso && strcmp(map->dso->name, name) == 0)
1212                         return map;
1213         }
1214
1215         return NULL;
1216 }
1217
1218 static int dsos__set_modules_path_dir(char *dirname)
1219 {
1220         struct dirent *dent;
1221         DIR *dir = opendir(dirname);
1222
1223         if (!dir) {
1224                 pr_debug("%s: cannot open %s dir\n", __func__, dirname);
1225                 return -1;
1226         }
1227
1228         while ((dent = readdir(dir)) != NULL) {
1229                 char path[PATH_MAX];
1230
1231                 if (dent->d_type == DT_DIR) {
1232                         if (!strcmp(dent->d_name, ".") ||
1233                             !strcmp(dent->d_name, ".."))
1234                                 continue;
1235
1236                         snprintf(path, sizeof(path), "%s/%s",
1237                                  dirname, dent->d_name);
1238                         if (dsos__set_modules_path_dir(path) < 0)
1239                                 goto failure;
1240                 } else {
1241                         char *dot = strrchr(dent->d_name, '.'),
1242                              dso_name[PATH_MAX];
1243                         struct map *map;
1244                         char *long_name;
1245
1246                         if (dot == NULL || strcmp(dot, ".ko"))
1247                                 continue;
1248                         snprintf(dso_name, sizeof(dso_name), "[%.*s]",
1249                                  (int)(dot - dent->d_name), dent->d_name);
1250
1251                         strxfrchar(dso_name, '-', '_');
1252                         map = thread__find_map_by_name(kthread, dso_name);
1253                         if (map == NULL)
1254                                 continue;
1255
1256                         snprintf(path, sizeof(path), "%s/%s",
1257                                  dirname, dent->d_name);
1258
1259                         long_name = strdup(path);
1260                         if (long_name == NULL)
1261                                 goto failure;
1262                         dso__set_long_name(map->dso, long_name);
1263                 }
1264         }
1265
1266         return 0;
1267 failure:
1268         closedir(dir);
1269         return -1;
1270 }
1271
1272 static int dsos__set_modules_path(void)
1273 {
1274         struct utsname uts;
1275         char modules_path[PATH_MAX];
1276
1277         if (uname(&uts) < 0)
1278                 return -1;
1279
1280         snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
1281                  uts.release);
1282
1283         return dsos__set_modules_path_dir(modules_path);
1284 }
1285
1286 /*
1287  * Constructor variant for modules (where we know from /proc/modules where
1288  * they are loaded) and for vmlinux, where only after we load all the
1289  * symbols we'll know where it starts and ends.
1290  */
1291 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
1292 {
1293         struct map *self = malloc(sizeof(*self));
1294
1295         if (self != NULL) {
1296                 /*
1297                  * ->end will be filled after we load all the symbols
1298                  */
1299                 map__init(self, type, start, 0, 0, dso);
1300         }
1301
1302         return self;
1303 }
1304
1305 static int thread__create_module_maps(struct thread *self)
1306 {
1307         char *line = NULL;
1308         size_t n;
1309         FILE *file = fopen("/proc/modules", "r");
1310         struct map *map;
1311
1312         if (file == NULL)
1313                 return -1;
1314
1315         while (!feof(file)) {
1316                 char name[PATH_MAX];
1317                 u64 start;
1318                 struct dso *dso;
1319                 char *sep;
1320                 int line_len;
1321
1322                 line_len = getline(&line, &n, file);
1323                 if (line_len < 0)
1324                         break;
1325
1326                 if (!line)
1327                         goto out_failure;
1328
1329                 line[--line_len] = '\0'; /* \n */
1330
1331                 sep = strrchr(line, 'x');
1332                 if (sep == NULL)
1333                         continue;
1334
1335                 hex2u64(sep + 1, &start);
1336
1337                 sep = strchr(line, ' ');
1338                 if (sep == NULL)
1339                         continue;
1340
1341                 *sep = '\0';
1342
1343                 snprintf(name, sizeof(name), "[%s]", line);
1344                 dso = dso__new(name);
1345
1346                 if (dso == NULL)
1347                         goto out_delete_line;
1348
1349                 map = map__new2(start, dso, MAP__FUNCTION);
1350                 if (map == NULL) {
1351                         dso__delete(dso);
1352                         goto out_delete_line;
1353                 }
1354
1355                 snprintf(name, sizeof(name),
1356                          "/sys/module/%s/notes/.note.gnu.build-id", line);
1357                 if (sysfs__read_build_id(name, dso->build_id,
1358                                          sizeof(dso->build_id)) == 0)
1359                         dso->has_build_id = true;
1360
1361                 dso->origin = DSO__ORIG_KMODULE;
1362                 __thread__insert_map(self, map);
1363                 dsos__add(&dsos__kernel, dso);
1364         }
1365
1366         free(line);
1367         fclose(file);
1368
1369         return dsos__set_modules_path();
1370
1371 out_delete_line:
1372         free(line);
1373 out_failure:
1374         return -1;
1375 }
1376
1377 static int dso__load_vmlinux(struct dso *self, struct map *map, struct thread *thread,
1378                              const char *vmlinux, symbol_filter_t filter)
1379 {
1380         int err = -1, fd;
1381
1382         if (self->has_build_id) {
1383                 u8 build_id[BUILD_ID_SIZE];
1384
1385                 if (filename__read_build_id(vmlinux, build_id,
1386                                             sizeof(build_id)) < 0) {
1387                         pr_debug("No build_id in %s, ignoring it\n", vmlinux);
1388                         return -1;
1389                 }
1390                 if (!dso__build_id_equal(self, build_id)) {
1391                         char expected_build_id[BUILD_ID_SIZE * 2 + 1],
1392                              vmlinux_build_id[BUILD_ID_SIZE * 2 + 1];
1393
1394                         build_id__sprintf(self->build_id,
1395                                           sizeof(self->build_id),
1396                                           expected_build_id);
1397                         build_id__sprintf(build_id, sizeof(build_id),
1398                                           vmlinux_build_id);
1399                         pr_debug("build_id in %s is %s while expected is %s, "
1400                                  "ignoring it\n", vmlinux, vmlinux_build_id,
1401                                  expected_build_id);
1402                         return -1;
1403                 }
1404         }
1405
1406         fd = open(vmlinux, O_RDONLY);
1407         if (fd < 0)
1408                 return -1;
1409
1410         dso__set_loaded(self, map->type);
1411         err = dso__load_sym(self, map, thread, self->long_name, fd, filter, 1, 0);
1412         close(fd);
1413
1414         return err;
1415 }
1416
1417 static int dso__load_kernel_sym(struct dso *self, struct map *map,
1418                                 struct thread *thread, symbol_filter_t filter)
1419 {
1420         int err;
1421         bool is_kallsyms;
1422
1423         if (vmlinux_path != NULL) {
1424                 int i;
1425                 pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1426                          vmlinux_path__nr_entries);
1427                 for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1428                         err = dso__load_vmlinux(self, map, thread,
1429                                                 vmlinux_path[i], filter);
1430                         if (err > 0) {
1431                                 pr_debug("Using %s for symbols\n",
1432                                          vmlinux_path[i]);
1433                                 dso__set_long_name(self,
1434                                                    strdup(vmlinux_path[i]));
1435                                 goto out_fixup;
1436                         }
1437                 }
1438         }
1439
1440         is_kallsyms = self->long_name[0] == '[';
1441         if (is_kallsyms)
1442                 goto do_kallsyms;
1443
1444         err = dso__load_vmlinux(self, map, thread, self->long_name, filter);
1445         if (err <= 0) {
1446                 pr_info("The file %s cannot be used, "
1447                         "trying to use /proc/kallsyms...", self->long_name);
1448 do_kallsyms:
1449                 err = dso__load_kallsyms(self, map, thread, filter);
1450                 if (err > 0 && !is_kallsyms)
1451                         dso__set_long_name(self, strdup("[kernel.kallsyms]"));
1452         }
1453
1454         if (err > 0) {
1455 out_fixup:
1456                 map__fixup_start(map);
1457                 map__fixup_end(map);
1458         }
1459
1460         return err;
1461 }
1462
1463 LIST_HEAD(dsos__user);
1464 LIST_HEAD(dsos__kernel);
1465 struct dso *vdso;
1466
1467 static void dsos__add(struct list_head *head, struct dso *dso)
1468 {
1469         list_add_tail(&dso->node, head);
1470 }
1471
1472 static struct dso *dsos__find(struct list_head *head, const char *name)
1473 {
1474         struct dso *pos;
1475
1476         list_for_each_entry(pos, head, node)
1477                 if (strcmp(pos->name, name) == 0)
1478                         return pos;
1479         return NULL;
1480 }
1481
1482 struct dso *dsos__findnew(const char *name)
1483 {
1484         struct dso *dso = dsos__find(&dsos__user, name);
1485
1486         if (!dso) {
1487                 dso = dso__new(name);
1488                 if (dso != NULL) {
1489                         dsos__add(&dsos__user, dso);
1490                         dso__set_basename(dso);
1491                 }
1492         }
1493
1494         return dso;
1495 }
1496
1497 static void __dsos__fprintf(struct list_head *head, FILE *fp)
1498 {
1499         struct dso *pos;
1500
1501         list_for_each_entry(pos, head, node) {
1502                 int i;
1503                 for (i = 0; i < MAP__NR_TYPES; ++i)
1504                         dso__fprintf(pos, i, fp);
1505         }
1506 }
1507
1508 void dsos__fprintf(FILE *fp)
1509 {
1510         __dsos__fprintf(&dsos__kernel, fp);
1511         __dsos__fprintf(&dsos__user, fp);
1512 }
1513
1514 static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp)
1515 {
1516         struct dso *pos;
1517         size_t ret = 0;
1518
1519         list_for_each_entry(pos, head, node) {
1520                 ret += dso__fprintf_buildid(pos, fp);
1521                 ret += fprintf(fp, " %s\n", pos->long_name);
1522         }
1523         return ret;
1524 }
1525
1526 size_t dsos__fprintf_buildid(FILE *fp)
1527 {
1528         return (__dsos__fprintf_buildid(&dsos__kernel, fp) +
1529                 __dsos__fprintf_buildid(&dsos__user, fp));
1530 }
1531
1532 static int thread__create_kernel_map(struct thread *self, const char *vmlinux)
1533 {
1534         struct map *kmap;
1535         struct dso *kernel = dso__new(vmlinux ?: "[kernel.kallsyms]");
1536
1537         if (kernel == NULL)
1538                 return -1;
1539
1540         kmap = map__new2(0, kernel, MAP__FUNCTION);
1541         if (kmap == NULL)
1542                 goto out_delete_kernel_dso;
1543
1544         kmap->map_ip       = kmap->unmap_ip = identity__map_ip;
1545         kernel->short_name = "[kernel]";
1546         kernel->kernel     = 1;
1547
1548         vdso = dso__new("[vdso]");
1549         if (vdso == NULL)
1550                 goto out_delete_kernel_map;
1551         dso__set_loaded(vdso, MAP__FUNCTION);
1552
1553         if (sysfs__read_build_id("/sys/kernel/notes", kernel->build_id,
1554                                  sizeof(kernel->build_id)) == 0)
1555                 kernel->has_build_id = true;
1556
1557         __thread__insert_map(self, kmap);
1558         dsos__add(&dsos__kernel, kernel);
1559         dsos__add(&dsos__user, vdso);
1560
1561         return 0;
1562
1563 out_delete_kernel_map:
1564         map__delete(kmap);
1565 out_delete_kernel_dso:
1566         dso__delete(kernel);
1567         return -1;
1568 }
1569
1570 static void vmlinux_path__exit(void)
1571 {
1572         while (--vmlinux_path__nr_entries >= 0) {
1573                 free(vmlinux_path[vmlinux_path__nr_entries]);
1574                 vmlinux_path[vmlinux_path__nr_entries] = NULL;
1575         }
1576
1577         free(vmlinux_path);
1578         vmlinux_path = NULL;
1579 }
1580
1581 static int vmlinux_path__init(void)
1582 {
1583         struct utsname uts;
1584         char bf[PATH_MAX];
1585
1586         if (uname(&uts) < 0)
1587                 return -1;
1588
1589         vmlinux_path = malloc(sizeof(char *) * 5);
1590         if (vmlinux_path == NULL)
1591                 return -1;
1592
1593         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1594         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1595                 goto out_fail;
1596         ++vmlinux_path__nr_entries;
1597         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1598         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1599                 goto out_fail;
1600         ++vmlinux_path__nr_entries;
1601         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
1602         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1603         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1604                 goto out_fail;
1605         ++vmlinux_path__nr_entries;
1606         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
1607         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1608         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1609                 goto out_fail;
1610         ++vmlinux_path__nr_entries;
1611         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1612                  uts.release);
1613         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1614         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1615                 goto out_fail;
1616         ++vmlinux_path__nr_entries;
1617
1618         return 0;
1619
1620 out_fail:
1621         vmlinux_path__exit();
1622         return -1;
1623 }
1624
1625 int symbol__init(struct symbol_conf *conf)
1626 {
1627         const struct symbol_conf *pconf = conf ?: &symbol_conf__defaults;
1628
1629         elf_version(EV_CURRENT);
1630         symbol__priv_size = pconf->priv_size;
1631         thread__init(kthread, 0);
1632
1633         if (pconf->try_vmlinux_path && vmlinux_path__init() < 0)
1634                 return -1;
1635
1636         if (thread__create_kernel_map(kthread, pconf->vmlinux_name) < 0) {
1637                 vmlinux_path__exit();
1638                 return -1;
1639         }
1640
1641         kthread->use_modules = pconf->use_modules;
1642         if (pconf->use_modules && thread__create_module_maps(kthread) < 0)
1643                 pr_debug("Failed to load list of modules in use, "
1644                          "continuing...\n");
1645         /*
1646          * Now that we have all the maps created, just set the ->end of them:
1647          */
1648         thread__fixup_maps_end(kthread);
1649         return 0;
1650 }