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