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

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