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