tools/perf/util/symbol.c

   1 #include <dirent.h>
   2 #include <errno.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <sys/param.h>
   9 #include <fcntl.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include "build-id.h"
  13 #include "util.h"
  14 #include "debug.h"
  15 #include "machine.h"
  16 #include "symbol.h"
  17 #include "strlist.h"
  18
  19 #include <elf.h>
  20 #include <limits.h>
  21 #include <sys/utsname.h>
  22
  23 #ifndef KSYM_NAME_LEN
  24 #define KSYM_NAME_LEN 256
  25 #endif
  26
  27 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
  28                                 symbol_filter_t filter);
  29 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
  30                         symbol_filter_t filter);
  31 int vmlinux_path__nr_entries;
  32 char **vmlinux_path;
  33
  34 struct symbol_conf symbol_conf = {
  35         .use_modules      = true,
  36         .try_vmlinux_path = true,
  37         .annotate_src     = true,
  38         .demangle         = true,
  39         .symfs            = "",
  40 };
  41
  42 static enum dso_binary_type binary_type_symtab[] = {
  43         DSO_BINARY_TYPE__KALLSYMS,
  44         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  45         DSO_BINARY_TYPE__JAVA_JIT,
  46         DSO_BINARY_TYPE__DEBUGLINK,
  47         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  48         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  49         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  50         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  51         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  52         DSO_BINARY_TYPE__GUEST_KMODULE,
  53         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  54         DSO_BINARY_TYPE__NOT_FOUND,
  55 };
  56
  57 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  58
  59 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  60 {
  61         symbol_type = toupper(symbol_type);
  62
  63         switch (map_type) {
  64         case MAP__FUNCTION:
  65                 return symbol_type == 'T' || symbol_type == 'W';
  66         case MAP__VARIABLE:
  67                 return symbol_type == 'D';
  68         default:
  69                 return false;
  70         }
  71 }
  72
  73 static int prefix_underscores_count(const char *str)
  74 {
  75         const char *tail = str;
  76
  77         while (*tail == '_')
  78                 tail++;
  79
  80         return tail - str;
  81 }
  82
  83 #define SYMBOL_A 0
  84 #define SYMBOL_B 1
  85
  86 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
  87 {
  88         s64 a;
  89         s64 b;
  90         size_t na, nb;
  91
  92         /* Prefer a symbol with non zero length */
  93         a = syma->end - syma->start;
  94         b = symb->end - symb->start;
  95         if ((b == 0) && (a > 0))
  96                 return SYMBOL_A;
  97         else if ((a == 0) && (b > 0))
  98                 return SYMBOL_B;
  99
 100         /* Prefer a non weak symbol over a weak one */
 101         a = syma->binding == STB_WEAK;
 102         b = symb->binding == STB_WEAK;
 103         if (b && !a)
 104                 return SYMBOL_A;
 105         if (a && !b)
 106                 return SYMBOL_B;
 107
 108         /* Prefer a global symbol over a non global one */
 109         a = syma->binding == STB_GLOBAL;
 110         b = symb->binding == STB_GLOBAL;
 111         if (a && !b)
 112                 return SYMBOL_A;
 113         if (b && !a)
 114                 return SYMBOL_B;
 115
 116         /* Prefer a symbol with less underscores */
 117         a = prefix_underscores_count(syma->name);
 118         b = prefix_underscores_count(symb->name);
 119         if (b > a)
 120                 return SYMBOL_A;
 121         else if (a > b)
 122                 return SYMBOL_B;
 123
 124         /* Choose the symbol with the longest name */
 125         na = strlen(syma->name);
 126         nb = strlen(symb->name);
 127         if (na > nb)
 128                 return SYMBOL_A;
 129         else if (na < nb)
 130                 return SYMBOL_B;
 131
 132         /* Avoid "SyS" kernel syscall aliases */
 133         if (na >= 3 && !strncmp(syma->name, "SyS", 3))
 134                 return SYMBOL_B;
 135         if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
 136                 return SYMBOL_B;
 137
 138         return SYMBOL_A;
 139 }
 140
 141 void symbols__fixup_duplicate(struct rb_root *symbols)
 142 {
 143         struct rb_node *nd;
 144         struct symbol *curr, *next;
 145
 146         nd = rb_first(symbols);
 147
 148         while (nd) {
 149                 curr = rb_entry(nd, struct symbol, rb_node);
 150 again:
 151                 nd = rb_next(&curr->rb_node);
 152                 next = rb_entry(nd, struct symbol, rb_node);
 153
 154                 if (!nd)
 155                         break;
 156
 157                 if (curr->start != next->start)
 158                         continue;
 159
 160                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 161                         rb_erase(&next->rb_node, symbols);
 162                         goto again;
 163                 } else {
 164                         nd = rb_next(&curr->rb_node);
 165                         rb_erase(&curr->rb_node, symbols);
 166                 }
 167         }
 168 }
 169
 170 void symbols__fixup_end(struct rb_root *symbols)
 171 {
 172         struct rb_node *nd, *prevnd = rb_first(symbols);
 173         struct symbol *curr, *prev;
 174
 175         if (prevnd == NULL)
 176                 return;
 177
 178         curr = rb_entry(prevnd, struct symbol, rb_node);
 179
 180         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 181                 prev = curr;
 182                 curr = rb_entry(nd, struct symbol, rb_node);
 183
 184                 if (prev->end == prev->start && prev->end != curr->start)
 185                         prev->end = curr->start - 1;
 186         }
 187
 188         /* Last entry */
 189         if (curr->end == curr->start)
 190                 curr->end = roundup(curr->start, 4096);
 191 }
 192
 193 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 194 {
 195         struct map *prev, *curr;
 196         struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
 197
 198         if (prevnd == NULL)
 199                 return;
 200
 201         curr = rb_entry(prevnd, struct map, rb_node);
 202
 203         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 204                 prev = curr;
 205                 curr = rb_entry(nd, struct map, rb_node);
 206                 prev->end = curr->start - 1;
 207         }
 208
 209         /*
 210          * We still haven't the actual symbols, so guess the
 211          * last map final address.
 212          */
 213         curr->end = ~0ULL;
 214 }
 215
 216 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 217 {
 218         size_t namelen = strlen(name) + 1;
 219         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 220                                         sizeof(*sym) + namelen));
 221         if (sym == NULL)
 222                 return NULL;
 223
 224         if (symbol_conf.priv_size)
 225                 sym = ((void *)sym) + symbol_conf.priv_size;
 226
 227         sym->start   = start;
 228         sym->end     = len ? start + len - 1 : start;
 229         sym->binding = binding;
 230         sym->namelen = namelen - 1;
 231
 232         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 233                   __func__, name, start, sym->end);
 234         memcpy(sym->name, name, namelen);
 235
 236         return sym;
 237 }
 238
 239 void symbol__delete(struct symbol *sym)
 240 {
 241         free(((void *)sym) - symbol_conf.priv_size);
 242 }
 243
 244 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 245 {
 246         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 247                        sym->start, sym->end,
 248                        sym->binding == STB_GLOBAL ? 'g' :
 249                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 250                        sym->name);
 251 }
 252
 253 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 254                                     const struct addr_location *al, FILE *fp)
 255 {
 256         unsigned long offset;
 257         size_t length;
 258
 259         if (sym && sym->name) {
 260                 length = fprintf(fp, "%s", sym->name);
 261                 if (al) {
 262                         offset = al->addr - sym->start;
 263                         length += fprintf(fp, "+0x%lx", offset);
 264                 }
 265                 return length;
 266         } else
 267                 return fprintf(fp, "[unknown]");
 268 }
 269
 270 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 271 {
 272         return symbol__fprintf_symname_offs(sym, NULL, fp);
 273 }
 274
 275 void symbols__delete(struct rb_root *symbols)
 276 {
 277         struct symbol *pos;
 278         struct rb_node *next = rb_first(symbols);
 279
 280         while (next) {
 281                 pos = rb_entry(next, struct symbol, rb_node);
 282                 next = rb_next(&pos->rb_node);
 283                 rb_erase(&pos->rb_node, symbols);
 284                 symbol__delete(pos);
 285         }
 286 }
 287
 288 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 289 {
 290         struct rb_node **p = &symbols->rb_node;
 291         struct rb_node *parent = NULL;
 292         const u64 ip = sym->start;
 293         struct symbol *s;
 294
 295         while (*p != NULL) {
 296                 parent = *p;
 297                 s = rb_entry(parent, struct symbol, rb_node);
 298                 if (ip < s->start)
 299                         p = &(*p)->rb_left;
 300                 else
 301                         p = &(*p)->rb_right;
 302         }
 303         rb_link_node(&sym->rb_node, parent, p);
 304         rb_insert_color(&sym->rb_node, symbols);
 305 }
 306
 307 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 308 {
 309         struct rb_node *n;
 310
 311         if (symbols == NULL)
 312                 return NULL;
 313
 314         n = symbols->rb_node;
 315
 316         while (n) {
 317                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 318
 319                 if (ip < s->start)
 320                         n = n->rb_left;
 321                 else if (ip > s->end)
 322                         n = n->rb_right;
 323                 else
 324                         return s;
 325         }
 326
 327         return NULL;
 328 }
 329
 330 struct symbol_name_rb_node {
 331         struct rb_node  rb_node;
 332         struct symbol   sym;
 333 };
 334
 335 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 336 {
 337         struct rb_node **p = &symbols->rb_node;
 338         struct rb_node *parent = NULL;
 339         struct symbol_name_rb_node *symn, *s;
 340
 341         symn = container_of(sym, struct symbol_name_rb_node, sym);
 342
 343         while (*p != NULL) {
 344                 parent = *p;
 345                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 346                 if (strcmp(sym->name, s->sym.name) < 0)
 347                         p = &(*p)->rb_left;
 348                 else
 349                         p = &(*p)->rb_right;
 350         }
 351         rb_link_node(&symn->rb_node, parent, p);
 352         rb_insert_color(&symn->rb_node, symbols);
 353 }
 354
 355 static void symbols__sort_by_name(struct rb_root *symbols,
 356                                   struct rb_root *source)
 357 {
 358         struct rb_node *nd;
 359
 360         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 361                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 362                 symbols__insert_by_name(symbols, pos);
 363         }
 364 }
 365
 366 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 367                                             const char *name)
 368 {
 369         struct rb_node *n;
 370
 371         if (symbols == NULL)
 372                 return NULL;
 373
 374         n = symbols->rb_node;
 375
 376         while (n) {
 377                 struct symbol_name_rb_node *s;
 378                 int cmp;
 379
 380                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 381                 cmp = strcmp(name, s->sym.name);
 382
 383                 if (cmp < 0)
 384                         n = n->rb_left;
 385                 else if (cmp > 0)
 386                         n = n->rb_right;
 387                 else
 388                         return &s->sym;
 389         }
 390
 391         return NULL;
 392 }
 393
 394 struct symbol *dso__find_symbol(struct dso *dso,
 395                                 enum map_type type, u64 addr)
 396 {
 397         return symbols__find(&dso->symbols[type], addr);
 398 }
 399
 400 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 401                                         const char *name)
 402 {
 403         return symbols__find_by_name(&dso->symbol_names[type], name);
 404 }
 405
 406 void dso__sort_by_name(struct dso *dso, enum map_type type)
 407 {
 408         dso__set_sorted_by_name(dso, type);
 409         return symbols__sort_by_name(&dso->symbol_names[type],
 410                                      &dso->symbols[type]);
 411 }
 412
 413 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 414                                     enum map_type type, FILE *fp)
 415 {
 416         size_t ret = 0;
 417         struct rb_node *nd;
 418         struct symbol_name_rb_node *pos;
 419
 420         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 421                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 422                 fprintf(fp, "%s\n", pos->sym.name);
 423         }
 424
 425         return ret;
 426 }
 427
 428 int kallsyms__parse(const char *filename, void *arg,
 429                     int (*process_symbol)(void *arg, const char *name,
 430                                           char type, u64 start))
 431 {
 432         char *line = NULL;
 433         size_t n;
 434         int err = -1;
 435         FILE *file = fopen(filename, "r");
 436
 437         if (file == NULL)
 438                 goto out_failure;
 439
 440         err = 0;
 441
 442         while (!feof(file)) {
 443                 u64 start;
 444                 int line_len, len;
 445                 char symbol_type;
 446                 char *symbol_name;
 447
 448                 line_len = getline(&line, &n, file);
 449                 if (line_len < 0 || !line)
 450                         break;
 451
 452                 line[--line_len] = '\0'; /* \n */
 453
 454                 len = hex2u64(line, &start);
 455
 456                 len++;
 457                 if (len + 2 >= line_len)
 458                         continue;
 459
 460                 symbol_type = line[len];
 461                 len += 2;
 462                 symbol_name = line + len;
 463                 len = line_len - len;
 464
 465                 if (len >= KSYM_NAME_LEN) {
 466                         err = -1;
 467                         break;
 468                 }
 469
 470                 err = process_symbol(arg, symbol_name,
 471                                      symbol_type, start);
 472                 if (err)
 473                         break;
 474         }
 475
 476         free(line);
 477         fclose(file);
 478         return err;
 479
 480 out_failure:
 481         return -1;
 482 }
 483
 484 struct process_kallsyms_args {
 485         struct map *map;
 486         struct dso *dso;
 487 };
 488
 489 static u8 kallsyms2elf_type(char type)
 490 {
 491         if (type == 'W')
 492                 return STB_WEAK;
 493
 494         return isupper(type) ? STB_GLOBAL : STB_LOCAL;
 495 }
 496
 497 static int map__process_kallsym_symbol(void *arg, const char *name,
 498                                        char type, u64 start)
 499 {
 500         struct symbol *sym;
 501         struct process_kallsyms_args *a = arg;
 502         struct rb_root *root = &a->dso->symbols[a->map->type];
 503
 504         if (!symbol_type__is_a(type, a->map->type))
 505                 return 0;
 506
 507         /*
 508          * module symbols are not sorted so we add all
 509          * symbols, setting length to 0, and rely on
 510          * symbols__fixup_end() to fix it up.
 511          */
 512         sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
 513         if (sym == NULL)
 514                 return -ENOMEM;
 515         /*
 516          * We will pass the symbols to the filter later, in
 517          * map__split_kallsyms, when we have split the maps per module
 518          */
 519         symbols__insert(root, sym);
 520
 521         return 0;
 522 }
 523
 524 /*
 525  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 526  * so that we can in the next step set the symbol ->end address and then
 527  * call kernel_maps__split_kallsyms.
 528  */
 529 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 530                                   struct map *map)
 531 {
 532         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 533         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 534 }
 535
 536 /*
 537  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 538  * kernel range is broken in several maps, named [kernel].N, as we don't have
 539  * the original ELF section names vmlinux have.
 540  */
 541 static int dso__split_kallsyms(struct dso *dso, struct map *map,
 542                                symbol_filter_t filter)
 543 {
 544         struct map_groups *kmaps = map__kmap(map)->kmaps;
 545         struct machine *machine = kmaps->machine;
 546         struct map *curr_map = map;
 547         struct symbol *pos;
 548         int count = 0, moved = 0;
 549         struct rb_root *root = &dso->symbols[map->type];
 550         struct rb_node *next = rb_first(root);
 551         int kernel_range = 0;
 552
 553         while (next) {
 554                 char *module;
 555
 556                 pos = rb_entry(next, struct symbol, rb_node);
 557                 next = rb_next(&pos->rb_node);
 558
 559                 module = strchr(pos->name, '\t');
 560                 if (module) {
 561                         if (!symbol_conf.use_modules)
 562                                 goto discard_symbol;
 563
 564                         *module++ = '\0';
 565
 566                         if (strcmp(curr_map->dso->short_name, module)) {
 567                                 if (curr_map != map &&
 568                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 569                                     machine__is_default_guest(machine)) {
 570                                         /*
 571                                          * We assume all symbols of a module are
 572                                          * continuous in * kallsyms, so curr_map
 573                                          * points to a module and all its
 574                                          * symbols are in its kmap. Mark it as
 575                                          * loaded.
 576                                          */
 577                                         dso__set_loaded(curr_map->dso,
 578                                                         curr_map->type);
 579                                 }
 580
 581                                 curr_map = map_groups__find_by_name(kmaps,
 582                                                         map->type, module);
 583                                 if (curr_map == NULL) {
 584                                         pr_debug("%s/proc/{kallsyms,modules} "
 585                                                  "inconsistency while looking "
 586                                                  "for \"%s\" module!\n",
 587                                                  machine->root_dir, module);
 588                                         curr_map = map;
 589                                         goto discard_symbol;
 590                                 }
 591
 592                                 if (curr_map->dso->loaded &&
 593                                     !machine__is_default_guest(machine))
 594                                         goto discard_symbol;
 595                         }
 596                         /*
 597                          * So that we look just like we get from .ko files,
 598                          * i.e. not prelinked, relative to map->start.
 599                          */
 600                         pos->start = curr_map->map_ip(curr_map, pos->start);
 601                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 602                 } else if (curr_map != map) {
 603                         char dso_name[PATH_MAX];
 604                         struct dso *ndso;
 605
 606                         if (count == 0) {
 607                                 curr_map = map;
 608                                 goto filter_symbol;
 609                         }
 610
 611                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 612                                 snprintf(dso_name, sizeof(dso_name),
 613                                         "[guest.kernel].%d",
 614                                         kernel_range++);
 615                         else
 616                                 snprintf(dso_name, sizeof(dso_name),
 617                                         "[kernel].%d",
 618                                         kernel_range++);
 619
 620                         ndso = dso__new(dso_name);
 621                         if (ndso == NULL)
 622                                 return -1;
 623
 624                         ndso->kernel = dso->kernel;
 625
 626                         curr_map = map__new2(pos->start, ndso, map->type);
 627                         if (curr_map == NULL) {
 628                                 dso__delete(ndso);
 629                                 return -1;
 630                         }
 631
 632                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 633                         map_groups__insert(kmaps, curr_map);
 634                         ++kernel_range;
 635                 }
 636 filter_symbol:
 637                 if (filter && filter(curr_map, pos)) {
 638 discard_symbol:         rb_erase(&pos->rb_node, root);
 639                         symbol__delete(pos);
 640                 } else {
 641                         if (curr_map != map) {
 642                                 rb_erase(&pos->rb_node, root);
 643                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 644                                 ++moved;
 645                         } else
 646                                 ++count;
 647                 }
 648         }
 649
 650         if (curr_map != map &&
 651             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 652             machine__is_default_guest(kmaps->machine)) {
 653                 dso__set_loaded(curr_map->dso, curr_map->type);
 654         }
 655
 656         return count + moved;
 657 }
 658
 659 bool symbol__restricted_filename(const char *filename,
 660                                  const char *restricted_filename)
 661 {
 662         bool restricted = false;
 663
 664         if (symbol_conf.kptr_restrict) {
 665                 char *r = realpath(filename, NULL);
 666
 667                 if (r != NULL) {
 668                         restricted = strcmp(r, restricted_filename) == 0;
 669                         free(r);
 670                         return restricted;
 671                 }
 672         }
 673
 674         return restricted;
 675 }
 676
 677 int dso__load_kallsyms(struct dso *dso, const char *filename,
 678                        struct map *map, symbol_filter_t filter)
 679 {
 680         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
 681                 return -1;
 682
 683         if (dso__load_all_kallsyms(dso, filename, map) < 0)
 684                 return -1;
 685
 686         symbols__fixup_duplicate(&dso->symbols[map->type]);
 687         symbols__fixup_end(&dso->symbols[map->type]);
 688
 689         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 690                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
 691         else
 692                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
 693
 694         return dso__split_kallsyms(dso, map, filter);
 695 }
 696
 697 static int dso__load_perf_map(struct dso *dso, struct map *map,
 698                               symbol_filter_t filter)
 699 {
 700         char *line = NULL;
 701         size_t n;
 702         FILE *file;
 703         int nr_syms = 0;
 704
 705         file = fopen(dso->long_name, "r");
 706         if (file == NULL)
 707                 goto out_failure;
 708
 709         while (!feof(file)) {
 710                 u64 start, size;
 711                 struct symbol *sym;
 712                 int line_len, len;
 713
 714                 line_len = getline(&line, &n, file);
 715                 if (line_len < 0)
 716                         break;
 717
 718                 if (!line)
 719                         goto out_failure;
 720
 721                 line[--line_len] = '\0'; /* \n */
 722
 723                 len = hex2u64(line, &start);
 724
 725                 len++;
 726                 if (len + 2 >= line_len)
 727                         continue;
 728
 729                 len += hex2u64(line + len, &size);
 730
 731                 len++;
 732                 if (len + 2 >= line_len)
 733                         continue;
 734
 735                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
 736
 737                 if (sym == NULL)
 738                         goto out_delete_line;
 739
 740                 if (filter && filter(map, sym))
 741                         symbol__delete(sym);
 742                 else {
 743                         symbols__insert(&dso->symbols[map->type], sym);
 744                         nr_syms++;
 745                 }
 746         }
 747
 748         free(line);
 749         fclose(file);
 750
 751         return nr_syms;
 752
 753 out_delete_line:
 754         free(line);
 755 out_failure:
 756         return -1;
 757 }
 758
 759 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 760 {
 761         char *name;
 762         int ret = -1;
 763         u_int i;
 764         struct machine *machine;
 765         char *root_dir = (char *) "";
 766         int ss_pos = 0;
 767         struct symsrc ss_[2];
 768         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
 769
 770         dso__set_loaded(dso, map->type);
 771
 772         if (dso->kernel == DSO_TYPE_KERNEL)
 773                 return dso__load_kernel_sym(dso, map, filter);
 774         else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 775                 return dso__load_guest_kernel_sym(dso, map, filter);
 776
 777         if (map->groups && map->groups->machine)
 778                 machine = map->groups->machine;
 779         else
 780                 machine = NULL;
 781
 782         dso->adjust_symbols = 0;
 783
 784         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
 785                 struct stat st;
 786
 787                 if (lstat(dso->name, &st) < 0)
 788                         return -1;
 789
 790                 if (st.st_uid && (st.st_uid != geteuid())) {
 791                         pr_warning("File %s not owned by current user or root, "
 792                                 "ignoring it.\n", dso->name);
 793                         return -1;
 794                 }
 795
 796                 ret = dso__load_perf_map(dso, map, filter);
 797                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
 798                                              DSO_BINARY_TYPE__NOT_FOUND;
 799                 return ret;
 800         }
 801
 802         if (machine)
 803                 root_dir = machine->root_dir;
 804
 805         name = malloc(PATH_MAX);
 806         if (!name)
 807                 return -1;
 808
 809         /* Iterate over candidate debug images.
 810          * Keep track of "interesting" ones (those which have a symtab, dynsym,
 811          * and/or opd section) for processing.
 812          */
 813         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
 814                 struct symsrc *ss = &ss_[ss_pos];
 815                 bool next_slot = false;
 816
 817                 enum dso_binary_type symtab_type = binary_type_symtab[i];
 818
 819                 if (dso__binary_type_file(dso, symtab_type,
 820                                           root_dir, name, PATH_MAX))
 821                         continue;
 822
 823                 /* Name is now the name of the next image to try */
 824                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
 825                         continue;
 826
 827                 if (!syms_ss && symsrc__has_symtab(ss)) {
 828                         syms_ss = ss;
 829                         next_slot = true;
 830                 }
 831
 832                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
 833                         runtime_ss = ss;
 834                         next_slot = true;
 835                 }
 836
 837                 if (next_slot) {
 838                         ss_pos++;
 839
 840                         if (syms_ss && runtime_ss)
 841                                 break;
 842                 }
 843
 844         }
 845
 846         if (!runtime_ss && !syms_ss)
 847                 goto out_free;
 848
 849         if (runtime_ss && !syms_ss) {
 850                 syms_ss = runtime_ss;
 851         }
 852
 853         /* We'll have to hope for the best */
 854         if (!runtime_ss && syms_ss)
 855                 runtime_ss = syms_ss;
 856
 857         if (syms_ss)
 858                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, 0);
 859         else
 860                 ret = -1;
 861
 862         if (ret > 0) {
 863                 int nr_plt;
 864
 865                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
 866                 if (nr_plt > 0)
 867                         ret += nr_plt;
 868         }
 869
 870         for (; ss_pos > 0; ss_pos--)
 871                 symsrc__destroy(&ss_[ss_pos - 1]);
 872 out_free:
 873         free(name);
 874         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
 875                 return 0;
 876         return ret;
 877 }
 878
 879 struct map *map_groups__find_by_name(struct map_groups *mg,
 880                                      enum map_type type, const char *name)
 881 {
 882         struct rb_node *nd;
 883
 884         for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
 885                 struct map *map = rb_entry(nd, struct map, rb_node);
 886
 887                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
 888                         return map;
 889         }
 890
 891         return NULL;
 892 }
 893
 894 int dso__load_vmlinux(struct dso *dso, struct map *map,
 895                       const char *vmlinux, symbol_filter_t filter)
 896 {
 897         int err = -1;
 898         struct symsrc ss;
 899         char symfs_vmlinux[PATH_MAX];
 900         enum dso_binary_type symtab_type;
 901
 902         if (vmlinux[0] == '/')
 903                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
 904         else
 905                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
 906                          symbol_conf.symfs, vmlinux);
 907
 908         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 909                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
 910         else
 911                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
 912
 913         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
 914                 return -1;
 915
 916         err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
 917         symsrc__destroy(&ss);
 918
 919         if (err > 0) {
 920                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 921                         dso->data_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
 922                 else
 923                         dso->data_type = DSO_BINARY_TYPE__VMLINUX;
 924                 dso__set_long_name(dso, (char *)vmlinux);
 925                 dso__set_loaded(dso, map->type);
 926                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
 927         }
 928
 929         return err;
 930 }
 931
 932 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
 933                            symbol_filter_t filter)
 934 {
 935         int i, err = 0;
 936         char *filename;
 937
 938         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
 939                  vmlinux_path__nr_entries + 1);
 940
 941         filename = dso__build_id_filename(dso, NULL, 0);
 942         if (filename != NULL) {
 943                 err = dso__load_vmlinux(dso, map, filename, filter);
 944                 if (err > 0) {
 945                         dso->lname_alloc = 1;
 946                         goto out;
 947                 }
 948                 free(filename);
 949         }
 950
 951         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
 952                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], filter);
 953                 if (err > 0) {
 954                         dso__set_long_name(dso, strdup(vmlinux_path[i]));
 955                         dso->lname_alloc = 1;
 956                         break;
 957                 }
 958         }
 959 out:
 960         return err;
 961 }
 962
 963 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
 964                                 symbol_filter_t filter)
 965 {
 966         int err;
 967         const char *kallsyms_filename = NULL;
 968         char *kallsyms_allocated_filename = NULL;
 969         /*
 970          * Step 1: if the user specified a kallsyms or vmlinux filename, use
 971          * it and only it, reporting errors to the user if it cannot be used.
 972          *
 973          * For instance, try to analyse an ARM perf.data file _without_ a
 974          * build-id, or if the user specifies the wrong path to the right
 975          * vmlinux file, obviously we can't fallback to another vmlinux (a
 976          * x86_86 one, on the machine where analysis is being performed, say),
 977          * or worse, /proc/kallsyms.
 978          *
 979          * If the specified file _has_ a build-id and there is a build-id
 980          * section in the perf.data file, we will still do the expected
 981          * validation in dso__load_vmlinux and will bail out if they don't
 982          * match.
 983          */
 984         if (symbol_conf.kallsyms_name != NULL) {
 985                 kallsyms_filename = symbol_conf.kallsyms_name;
 986                 goto do_kallsyms;
 987         }
 988
 989         if (symbol_conf.vmlinux_name != NULL) {
 990                 err = dso__load_vmlinux(dso, map,
 991                                         symbol_conf.vmlinux_name, filter);
 992                 if (err > 0) {
 993                         dso__set_long_name(dso,
 994                                            strdup(symbol_conf.vmlinux_name));
 995                         dso->lname_alloc = 1;
 996                         return err;
 997                 }
 998                 return err;
 999         }
1000
1001         if (vmlinux_path != NULL) {
1002                 err = dso__load_vmlinux_path(dso, map, filter);
1003                 if (err > 0)
1004                         return err;
1005         }
1006
1007         /* do not try local files if a symfs was given */
1008         if (symbol_conf.symfs[0] != 0)
1009                 return -1;
1010
1011         /*
1012          * Say the kernel DSO was created when processing the build-id header table,
1013          * we have a build-id, so check if it is the same as the running kernel,
1014          * using it if it is.
1015          */
1016         if (dso->has_build_id) {
1017                 u8 kallsyms_build_id[BUILD_ID_SIZE];
1018                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1019
1020                 if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
1021                                          sizeof(kallsyms_build_id)) == 0) {
1022                         if (dso__build_id_equal(dso, kallsyms_build_id)) {
1023                                 kallsyms_filename = "/proc/kallsyms";
1024                                 goto do_kallsyms;
1025                         }
1026                 }
1027                 /*
1028                  * Now look if we have it on the build-id cache in
1029                  * $HOME/.debug/[kernel.kallsyms].
1030                  */
1031                 build_id__sprintf(dso->build_id, sizeof(dso->build_id),
1032                                   sbuild_id);
1033
1034                 if (asprintf(&kallsyms_allocated_filename,
1035                              "%s/.debug/[kernel.kallsyms]/%s",
1036                              getenv("HOME"), sbuild_id) == -1) {
1037                         pr_err("Not enough memory for kallsyms file lookup\n");
1038                         return -1;
1039                 }
1040
1041                 kallsyms_filename = kallsyms_allocated_filename;
1042
1043                 if (access(kallsyms_filename, F_OK)) {
1044                         pr_err("No kallsyms or vmlinux with build-id %s "
1045                                "was found\n", sbuild_id);
1046                         free(kallsyms_allocated_filename);
1047                         return -1;
1048                 }
1049         } else {
1050                 /*
1051                  * Last resort, if we don't have a build-id and couldn't find
1052                  * any vmlinux file, try the running kernel kallsyms table.
1053                  */
1054                 kallsyms_filename = "/proc/kallsyms";
1055         }
1056
1057 do_kallsyms:
1058         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1059         if (err > 0)
1060                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1061         free(kallsyms_allocated_filename);
1062
1063         if (err > 0) {
1064                 dso__set_long_name(dso, strdup("[kernel.kallsyms]"));
1065                 map__fixup_start(map);
1066                 map__fixup_end(map);
1067         }
1068
1069         return err;
1070 }
1071
1072 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1073                                       symbol_filter_t filter)
1074 {
1075         int err;
1076         const char *kallsyms_filename = NULL;
1077         struct machine *machine;
1078         char path[PATH_MAX];
1079
1080         if (!map->groups) {
1081                 pr_debug("Guest kernel map hasn't the point to groups\n");
1082                 return -1;
1083         }
1084         machine = map->groups->machine;
1085
1086         if (machine__is_default_guest(machine)) {
1087                 /*
1088                  * if the user specified a vmlinux filename, use it and only
1089                  * it, reporting errors to the user if it cannot be used.
1090                  * Or use file guest_kallsyms inputted by user on commandline
1091                  */
1092                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1093                         err = dso__load_vmlinux(dso, map,
1094                                 symbol_conf.default_guest_vmlinux_name, filter);
1095                         return err;
1096                 }
1097
1098                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1099                 if (!kallsyms_filename)
1100                         return -1;
1101         } else {
1102                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1103                 kallsyms_filename = path;
1104         }
1105
1106         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1107         if (err > 0) {
1108                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1109                 machine__mmap_name(machine, path, sizeof(path));
1110                 dso__set_long_name(dso, strdup(path));
1111                 map__fixup_start(map);
1112                 map__fixup_end(map);
1113         }
1114
1115         return err;
1116 }
1117
1118 static void vmlinux_path__exit(void)
1119 {
1120         while (--vmlinux_path__nr_entries >= 0) {
1121                 free(vmlinux_path[vmlinux_path__nr_entries]);
1122                 vmlinux_path[vmlinux_path__nr_entries] = NULL;
1123         }
1124
1125         free(vmlinux_path);
1126         vmlinux_path = NULL;
1127 }
1128
1129 static int vmlinux_path__init(void)
1130 {
1131         struct utsname uts;
1132         char bf[PATH_MAX];
1133
1134         vmlinux_path = malloc(sizeof(char *) * 5);
1135         if (vmlinux_path == NULL)
1136                 return -1;
1137
1138         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1139         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1140                 goto out_fail;
1141         ++vmlinux_path__nr_entries;
1142         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1143         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1144                 goto out_fail;
1145         ++vmlinux_path__nr_entries;
1146
1147         /* only try running kernel version if no symfs was given */
1148         if (symbol_conf.symfs[0] != 0)
1149                 return 0;
1150
1151         if (uname(&uts) < 0)
1152                 return -1;
1153
1154         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
1155         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1156         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1157                 goto out_fail;
1158         ++vmlinux_path__nr_entries;
1159         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
1160         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1161         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1162                 goto out_fail;
1163         ++vmlinux_path__nr_entries;
1164         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1165                  uts.release);
1166         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1167         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1168                 goto out_fail;
1169         ++vmlinux_path__nr_entries;
1170
1171         return 0;
1172
1173 out_fail:
1174         vmlinux_path__exit();
1175         return -1;
1176 }
1177
1178 static int setup_list(struct strlist **list, const char *list_str,
1179                       const char *list_name)
1180 {
1181         if (list_str == NULL)
1182                 return 0;
1183
1184         *list = strlist__new(true, list_str);
1185         if (!*list) {
1186                 pr_err("problems parsing %s list\n", list_name);
1187                 return -1;
1188         }
1189         return 0;
1190 }
1191
1192 static bool symbol__read_kptr_restrict(void)
1193 {
1194         bool value = false;
1195
1196         if (geteuid() != 0) {
1197                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1198                 if (fp != NULL) {
1199                         char line[8];
1200
1201                         if (fgets(line, sizeof(line), fp) != NULL)
1202                                 value = atoi(line) != 0;
1203
1204                         fclose(fp);
1205                 }
1206         }
1207
1208         return value;
1209 }
1210
1211 int symbol__init(void)
1212 {
1213         const char *symfs;
1214
1215         if (symbol_conf.initialized)
1216                 return 0;
1217
1218         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1219
1220         symbol__elf_init();
1221
1222         if (symbol_conf.sort_by_name)
1223                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1224                                           sizeof(struct symbol));
1225
1226         if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1227                 return -1;
1228
1229         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1230                 pr_err("'.' is the only non valid --field-separator argument\n");
1231                 return -1;
1232         }
1233
1234         if (setup_list(&symbol_conf.dso_list,
1235                        symbol_conf.dso_list_str, "dso") < 0)
1236                 return -1;
1237
1238         if (setup_list(&symbol_conf.comm_list,
1239                        symbol_conf.comm_list_str, "comm") < 0)
1240                 goto out_free_dso_list;
1241
1242         if (setup_list(&symbol_conf.sym_list,
1243                        symbol_conf.sym_list_str, "symbol") < 0)
1244                 goto out_free_comm_list;
1245
1246         /*
1247          * A path to symbols of "/" is identical to ""
1248          * reset here for simplicity.
1249          */
1250         symfs = realpath(symbol_conf.symfs, NULL);
1251         if (symfs == NULL)
1252                 symfs = symbol_conf.symfs;
1253         if (strcmp(symfs, "/") == 0)
1254                 symbol_conf.symfs = "";
1255         if (symfs != symbol_conf.symfs)
1256                 free((void *)symfs);
1257
1258         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
1259
1260         symbol_conf.initialized = true;
1261         return 0;
1262
1263 out_free_comm_list:
1264         strlist__delete(symbol_conf.comm_list);
1265 out_free_dso_list:
1266         strlist__delete(symbol_conf.dso_list);
1267         return -1;
1268 }
1269
1270 void symbol__exit(void)
1271 {
1272         if (!symbol_conf.initialized)
1273                 return;
1274         strlist__delete(symbol_conf.sym_list);
1275         strlist__delete(symbol_conf.dso_list);
1276         strlist__delete(symbol_conf.comm_list);
1277         vmlinux_path__exit();
1278         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
1279         symbol_conf.initialized = false;
1280 }