Pileus Git - ~andy/linux/blob - tools/perf/util/map.c

   1 #include "symbol.h"
   2 #include <errno.h>
   3 #include <inttypes.h>
   4 #include <limits.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <stdio.h>
   8 #include <unistd.h>
   9 #include "map.h"
  10 #include "thread.h"
  11 #include "strlist.h"
  12 #include "vdso.h"
  13
  14 const char *map_type__name[MAP__NR_TYPES] = {
  15         [MAP__FUNCTION] = "Functions",
  16         [MAP__VARIABLE] = "Variables",
  17 };
  18
  19 static inline int is_anon_memory(const char *filename)
  20 {
  21         return strcmp(filename, "//anon") == 0;
  22 }
  23
  24 static inline int is_no_dso_memory(const char *filename)
  25 {
  26         return !strcmp(filename, "[stack]") ||
  27                !strcmp(filename, "[heap]");
  28 }
  29
  30 void map__init(struct map *self, enum map_type type,
  31                u64 start, u64 end, u64 pgoff, struct dso *dso)
  32 {
  33         self->type     = type;
  34         self->start    = start;
  35         self->end      = end;
  36         self->pgoff    = pgoff;
  37         self->dso      = dso;
  38         self->map_ip   = map__map_ip;
  39         self->unmap_ip = map__unmap_ip;
  40         RB_CLEAR_NODE(&self->rb_node);
  41         self->groups   = NULL;
  42         self->referenced = false;
  43         self->erange_warned = false;
  44 }
  45
  46 struct map *map__new(struct list_head *dsos__list, u64 start, u64 len,
  47                      u64 pgoff, u32 pid, char *filename,
  48                      enum map_type type)
  49 {
  50         struct map *self = malloc(sizeof(*self));
  51
  52         if (self != NULL) {
  53                 char newfilename[PATH_MAX];
  54                 struct dso *dso;
  55                 int anon, no_dso, vdso;
  56
  57                 anon = is_anon_memory(filename);
  58                 vdso = is_vdso_map(filename);
  59                 no_dso = is_no_dso_memory(filename);
  60
  61                 if (anon) {
  62                         snprintf(newfilename, sizeof(newfilename), "/tmp/perf-%d.map", pid);
  63                         filename = newfilename;
  64                 }
  65
  66                 if (vdso) {
  67                         pgoff = 0;
  68                         dso = vdso__dso_findnew(dsos__list);
  69                 } else
  70                         dso = __dsos__findnew(dsos__list, filename);
  71
  72                 if (dso == NULL)
  73                         goto out_delete;
  74
  75                 map__init(self, type, start, start + len, pgoff, dso);
  76
  77                 if (anon || no_dso) {
  78                         self->map_ip = self->unmap_ip = identity__map_ip;
  79
  80                         /*
  81                          * Set memory without DSO as loaded. All map__find_*
  82                          * functions still return NULL, and we avoid the
  83                          * unnecessary map__load warning.
  84                          */
  85                         if (no_dso)
  86                                 dso__set_loaded(dso, self->type);
  87                 }
  88         }
  89         return self;
  90 out_delete:
  91         free(self);
  92         return NULL;
  93 }
  94
  95 /*
  96  * Constructor variant for modules (where we know from /proc/modules where
  97  * they are loaded) and for vmlinux, where only after we load all the
  98  * symbols we'll know where it starts and ends.
  99  */
 100 struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
 101 {
 102         struct map *map = calloc(1, (sizeof(*map) +
 103                                      (dso->kernel ? sizeof(struct kmap) : 0)));
 104         if (map != NULL) {
 105                 /*
 106                  * ->end will be filled after we load all the symbols
 107                  */
 108                 map__init(map, type, start, 0, 0, dso);
 109         }
 110
 111         return map;
 112 }
 113
 114 void map__delete(struct map *self)
 115 {
 116         free(self);
 117 }
 118
 119 void map__fixup_start(struct map *self)
 120 {
 121         struct rb_root *symbols = &self->dso->symbols[self->type];
 122         struct rb_node *nd = rb_first(symbols);
 123         if (nd != NULL) {
 124                 struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
 125                 self->start = sym->start;
 126         }
 127 }
 128
 129 void map__fixup_end(struct map *self)
 130 {
 131         struct rb_root *symbols = &self->dso->symbols[self->type];
 132         struct rb_node *nd = rb_last(symbols);
 133         if (nd != NULL) {
 134                 struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
 135                 self->end = sym->end;
 136         }
 137 }
 138
 139 #define DSO__DELETED "(deleted)"
 140
 141 int map__load(struct map *self, symbol_filter_t filter)
 142 {
 143         const char *name = self->dso->long_name;
 144         int nr;
 145
 146         if (dso__loaded(self->dso, self->type))
 147                 return 0;
 148
 149         nr = dso__load(self->dso, self, filter);
 150         if (nr < 0) {
 151                 if (self->dso->has_build_id) {
 152                         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
 153
 154                         build_id__sprintf(self->dso->build_id,
 155                                           sizeof(self->dso->build_id),
 156                                           sbuild_id);
 157                         pr_warning("%s with build id %s not found",
 158                                    name, sbuild_id);
 159                 } else
 160                         pr_warning("Failed to open %s", name);
 161
 162                 pr_warning(", continuing without symbols\n");
 163                 return -1;
 164         } else if (nr == 0) {
 165 #ifdef LIBELF_SUPPORT
 166                 const size_t len = strlen(name);
 167                 const size_t real_len = len - sizeof(DSO__DELETED);
 168
 169                 if (len > sizeof(DSO__DELETED) &&
 170                     strcmp(name + real_len + 1, DSO__DELETED) == 0) {
 171                         pr_warning("%.*s was updated (is prelink enabled?). "
 172                                 "Restart the long running apps that use it!\n",
 173                                    (int)real_len, name);
 174                 } else {
 175                         pr_warning("no symbols found in %s, maybe install "
 176                                    "a debug package?\n", name);
 177                 }
 178 #endif
 179                 return -1;
 180         }
 181         /*
 182          * Only applies to the kernel, as its symtabs aren't relative like the
 183          * module ones.
 184          */
 185         if (self->dso->kernel)
 186                 map__reloc_vmlinux(self);
 187
 188         return 0;
 189 }
 190
 191 struct symbol *map__find_symbol(struct map *self, u64 addr,
 192                                 symbol_filter_t filter)
 193 {
 194         if (map__load(self, filter) < 0)
 195                 return NULL;
 196
 197         return dso__find_symbol(self->dso, self->type, addr);
 198 }
 199
 200 struct symbol *map__find_symbol_by_name(struct map *self, const char *name,
 201                                         symbol_filter_t filter)
 202 {
 203         if (map__load(self, filter) < 0)
 204                 return NULL;
 205
 206         if (!dso__sorted_by_name(self->dso, self->type))
 207                 dso__sort_by_name(self->dso, self->type);
 208
 209         return dso__find_symbol_by_name(self->dso, self->type, name);
 210 }
 211
 212 struct map *map__clone(struct map *self)
 213 {
 214         struct map *map = malloc(sizeof(*self));
 215
 216         if (!map)
 217                 return NULL;
 218
 219         memcpy(map, self, sizeof(*self));
 220
 221         return map;
 222 }
 223
 224 int map__overlap(struct map *l, struct map *r)
 225 {
 226         if (l->start > r->start) {
 227                 struct map *t = l;
 228                 l = r;
 229                 r = t;
 230         }
 231
 232         if (l->end > r->start)
 233                 return 1;
 234
 235         return 0;
 236 }
 237
 238 size_t map__fprintf(struct map *self, FILE *fp)
 239 {
 240         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
 241                        self->start, self->end, self->pgoff, self->dso->name);
 242 }
 243
 244 size_t map__fprintf_dsoname(struct map *map, FILE *fp)
 245 {
 246         const char *dsoname = "[unknown]";
 247
 248         if (map && map->dso && (map->dso->name || map->dso->long_name)) {
 249                 if (symbol_conf.show_kernel_path && map->dso->long_name)
 250                         dsoname = map->dso->long_name;
 251                 else if (map->dso->name)
 252                         dsoname = map->dso->name;
 253         }
 254
 255         return fprintf(fp, "%s", dsoname);
 256 }
 257
 258 /*
 259  * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
 260  * map->dso->adjust_symbols==1 for ET_EXEC-like cases.
 261  */
 262 u64 map__rip_2objdump(struct map *map, u64 rip)
 263 {
 264         u64 addr = map->dso->adjust_symbols ?
 265                         map->unmap_ip(map, rip) :       /* RIP -> IP */
 266                         rip;
 267         return addr;
 268 }
 269
 270 void map_groups__init(struct map_groups *mg)
 271 {
 272         int i;
 273         for (i = 0; i < MAP__NR_TYPES; ++i) {
 274                 mg->maps[i] = RB_ROOT;
 275                 INIT_LIST_HEAD(&mg->removed_maps[i]);
 276         }
 277         mg->machine = NULL;
 278 }
 279
 280 static void maps__delete(struct rb_root *maps)
 281 {
 282         struct rb_node *next = rb_first(maps);
 283
 284         while (next) {
 285                 struct map *pos = rb_entry(next, struct map, rb_node);
 286
 287                 next = rb_next(&pos->rb_node);
 288                 rb_erase(&pos->rb_node, maps);
 289                 map__delete(pos);
 290         }
 291 }
 292
 293 static void maps__delete_removed(struct list_head *maps)
 294 {
 295         struct map *pos, *n;
 296
 297         list_for_each_entry_safe(pos, n, maps, node) {
 298                 list_del(&pos->node);
 299                 map__delete(pos);
 300         }
 301 }
 302
 303 void map_groups__exit(struct map_groups *mg)
 304 {
 305         int i;
 306
 307         for (i = 0; i < MAP__NR_TYPES; ++i) {
 308                 maps__delete(&mg->maps[i]);
 309                 maps__delete_removed(&mg->removed_maps[i]);
 310         }
 311 }
 312
 313 void map_groups__flush(struct map_groups *mg)
 314 {
 315         int type;
 316
 317         for (type = 0; type < MAP__NR_TYPES; type++) {
 318                 struct rb_root *root = &mg->maps[type];
 319                 struct rb_node *next = rb_first(root);
 320
 321                 while (next) {
 322                         struct map *pos = rb_entry(next, struct map, rb_node);
 323                         next = rb_next(&pos->rb_node);
 324                         rb_erase(&pos->rb_node, root);
 325                         /*
 326                          * We may have references to this map, for
 327                          * instance in some hist_entry instances, so
 328                          * just move them to a separate list.
 329                          */
 330                         list_add_tail(&pos->node, &mg->removed_maps[pos->type]);
 331                 }
 332         }
 333 }
 334
 335 struct symbol *map_groups__find_symbol(struct map_groups *mg,
 336                                        enum map_type type, u64 addr,
 337                                        struct map **mapp,
 338                                        symbol_filter_t filter)
 339 {
 340         struct map *map = map_groups__find(mg, type, addr);
 341
 342         if (map != NULL) {
 343                 if (mapp != NULL)
 344                         *mapp = map;
 345                 return map__find_symbol(map, map->map_ip(map, addr), filter);
 346         }
 347
 348         return NULL;
 349 }
 350
 351 struct symbol *map_groups__find_symbol_by_name(struct map_groups *mg,
 352                                                enum map_type type,
 353                                                const char *name,
 354                                                struct map **mapp,
 355                                                symbol_filter_t filter)
 356 {
 357         struct rb_node *nd;
 358
 359         for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
 360                 struct map *pos = rb_entry(nd, struct map, rb_node);
 361                 struct symbol *sym = map__find_symbol_by_name(pos, name, filter);
 362
 363                 if (sym == NULL)
 364                         continue;
 365                 if (mapp != NULL)
 366                         *mapp = pos;
 367                 return sym;
 368         }
 369
 370         return NULL;
 371 }
 372
 373 size_t __map_groups__fprintf_maps(struct map_groups *mg,
 374                                   enum map_type type, int verbose, FILE *fp)
 375 {
 376         size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
 377         struct rb_node *nd;
 378
 379         for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
 380                 struct map *pos = rb_entry(nd, struct map, rb_node);
 381                 printed += fprintf(fp, "Map:");
 382                 printed += map__fprintf(pos, fp);
 383                 if (verbose > 2) {
 384                         printed += dso__fprintf(pos->dso, type, fp);
 385                         printed += fprintf(fp, "--\n");
 386                 }
 387         }
 388
 389         return printed;
 390 }
 391
 392 size_t map_groups__fprintf_maps(struct map_groups *mg, int verbose, FILE *fp)
 393 {
 394         size_t printed = 0, i;
 395         for (i = 0; i < MAP__NR_TYPES; ++i)
 396                 printed += __map_groups__fprintf_maps(mg, i, verbose, fp);
 397         return printed;
 398 }
 399
 400 static size_t __map_groups__fprintf_removed_maps(struct map_groups *mg,
 401                                                  enum map_type type,
 402                                                  int verbose, FILE *fp)
 403 {
 404         struct map *pos;
 405         size_t printed = 0;
 406
 407         list_for_each_entry(pos, &mg->removed_maps[type], node) {
 408                 printed += fprintf(fp, "Map:");
 409                 printed += map__fprintf(pos, fp);
 410                 if (verbose > 1) {
 411                         printed += dso__fprintf(pos->dso, type, fp);
 412                         printed += fprintf(fp, "--\n");
 413                 }
 414         }
 415         return printed;
 416 }
 417
 418 static size_t map_groups__fprintf_removed_maps(struct map_groups *mg,
 419                                                int verbose, FILE *fp)
 420 {
 421         size_t printed = 0, i;
 422         for (i = 0; i < MAP__NR_TYPES; ++i)
 423                 printed += __map_groups__fprintf_removed_maps(mg, i, verbose, fp);
 424         return printed;
 425 }
 426
 427 size_t map_groups__fprintf(struct map_groups *mg, int verbose, FILE *fp)
 428 {
 429         size_t printed = map_groups__fprintf_maps(mg, verbose, fp);
 430         printed += fprintf(fp, "Removed maps:\n");
 431         return printed + map_groups__fprintf_removed_maps(mg, verbose, fp);
 432 }
 433
 434 int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
 435                                    int verbose, FILE *fp)
 436 {
 437         struct rb_root *root = &mg->maps[map->type];
 438         struct rb_node *next = rb_first(root);
 439         int err = 0;
 440
 441         while (next) {
 442                 struct map *pos = rb_entry(next, struct map, rb_node);
 443                 next = rb_next(&pos->rb_node);
 444
 445                 if (!map__overlap(pos, map))
 446                         continue;
 447
 448                 if (verbose >= 2) {
 449                         fputs("overlapping maps:\n", fp);
 450                         map__fprintf(map, fp);
 451                         map__fprintf(pos, fp);
 452                 }
 453
 454                 rb_erase(&pos->rb_node, root);
 455                 /*
 456                  * Now check if we need to create new maps for areas not
 457                  * overlapped by the new map:
 458                  */
 459                 if (map->start > pos->start) {
 460                         struct map *before = map__clone(pos);
 461
 462                         if (before == NULL) {
 463                                 err = -ENOMEM;
 464                                 goto move_map;
 465                         }
 466
 467                         before->end = map->start - 1;
 468                         map_groups__insert(mg, before);
 469                         if (verbose >= 2)
 470                                 map__fprintf(before, fp);
 471                 }
 472
 473                 if (map->end < pos->end) {
 474                         struct map *after = map__clone(pos);
 475
 476                         if (after == NULL) {
 477                                 err = -ENOMEM;
 478                                 goto move_map;
 479                         }
 480
 481                         after->start = map->end + 1;
 482                         map_groups__insert(mg, after);
 483                         if (verbose >= 2)
 484                                 map__fprintf(after, fp);
 485                 }
 486 move_map:
 487                 /*
 488                  * If we have references, just move them to a separate list.
 489                  */
 490                 if (pos->referenced)
 491                         list_add_tail(&pos->node, &mg->removed_maps[map->type]);
 492                 else
 493                         map__delete(pos);
 494
 495                 if (err)
 496                         return err;
 497         }
 498
 499         return 0;
 500 }
 501
 502 /*
 503  * XXX This should not really _copy_ te maps, but refcount them.
 504  */
 505 int map_groups__clone(struct map_groups *mg,
 506                       struct map_groups *parent, enum map_type type)
 507 {
 508         struct rb_node *nd;
 509         for (nd = rb_first(&parent->maps[type]); nd; nd = rb_next(nd)) {
 510                 struct map *map = rb_entry(nd, struct map, rb_node);
 511                 struct map *new = map__clone(map);
 512                 if (new == NULL)
 513                         return -ENOMEM;
 514                 map_groups__insert(mg, new);
 515         }
 516         return 0;
 517 }
 518
 519 static u64 map__reloc_map_ip(struct map *map, u64 ip)
 520 {
 521         return ip + (s64)map->pgoff;
 522 }
 523
 524 static u64 map__reloc_unmap_ip(struct map *map, u64 ip)
 525 {
 526         return ip - (s64)map->pgoff;
 527 }
 528
 529 void map__reloc_vmlinux(struct map *self)
 530 {
 531         struct kmap *kmap = map__kmap(self);
 532         s64 reloc;
 533
 534         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->unrelocated_addr)
 535                 return;
 536
 537         reloc = (kmap->ref_reloc_sym->unrelocated_addr -
 538                  kmap->ref_reloc_sym->addr);
 539
 540         if (!reloc)
 541                 return;
 542
 543         self->map_ip   = map__reloc_map_ip;
 544         self->unmap_ip = map__reloc_unmap_ip;
 545         self->pgoff    = reloc;
 546 }
 547
 548 void maps__insert(struct rb_root *maps, struct map *map)
 549 {
 550         struct rb_node **p = &maps->rb_node;
 551         struct rb_node *parent = NULL;
 552         const u64 ip = map->start;
 553         struct map *m;
 554
 555         while (*p != NULL) {
 556                 parent = *p;
 557                 m = rb_entry(parent, struct map, rb_node);
 558                 if (ip < m->start)
 559                         p = &(*p)->rb_left;
 560                 else
 561                         p = &(*p)->rb_right;
 562         }
 563
 564         rb_link_node(&map->rb_node, parent, p);
 565         rb_insert_color(&map->rb_node, maps);
 566 }
 567
 568 void maps__remove(struct rb_root *self, struct map *map)
 569 {
 570         rb_erase(&map->rb_node, self);
 571 }
 572
 573 struct map *maps__find(struct rb_root *maps, u64 ip)
 574 {
 575         struct rb_node **p = &maps->rb_node;
 576         struct rb_node *parent = NULL;
 577         struct map *m;
 578
 579         while (*p != NULL) {
 580                 parent = *p;
 581                 m = rb_entry(parent, struct map, rb_node);
 582                 if (ip < m->start)
 583                         p = &(*p)->rb_left;
 584                 else if (ip > m->end)
 585                         p = &(*p)->rb_right;
 586                 else
 587                         return m;
 588         }
 589
 590         return NULL;
 591 }
 592
 593 int machine__init(struct machine *self, const char *root_dir, pid_t pid)
 594 {
 595         map_groups__init(&self->kmaps);
 596         RB_CLEAR_NODE(&self->rb_node);
 597         INIT_LIST_HEAD(&self->user_dsos);
 598         INIT_LIST_HEAD(&self->kernel_dsos);
 599
 600         self->threads = RB_ROOT;
 601         INIT_LIST_HEAD(&self->dead_threads);
 602         self->last_match = NULL;
 603
 604         self->kmaps.machine = self;
 605         self->pid           = pid;
 606         self->root_dir      = strdup(root_dir);
 607         if (self->root_dir == NULL)
 608                 return -ENOMEM;
 609
 610         if (pid != HOST_KERNEL_ID) {
 611                 struct thread *thread = machine__findnew_thread(self, pid);
 612                 char comm[64];
 613
 614                 if (thread == NULL)
 615                         return -ENOMEM;
 616
 617                 snprintf(comm, sizeof(comm), "[guest/%d]", pid);
 618                 thread__set_comm(thread, comm);
 619         }
 620
 621         return 0;
 622 }
 623
 624 static void dsos__delete(struct list_head *self)
 625 {
 626         struct dso *pos, *n;
 627
 628         list_for_each_entry_safe(pos, n, self, node) {
 629                 list_del(&pos->node);
 630                 dso__delete(pos);
 631         }
 632 }
 633
 634 void machine__exit(struct machine *self)
 635 {
 636         map_groups__exit(&self->kmaps);
 637         dsos__delete(&self->user_dsos);
 638         dsos__delete(&self->kernel_dsos);
 639         free(self->root_dir);
 640         self->root_dir = NULL;
 641 }
 642
 643 void machine__delete(struct machine *self)
 644 {
 645         machine__exit(self);
 646         free(self);
 647 }
 648
 649 struct machine *machines__add(struct rb_root *self, pid_t pid,
 650                               const char *root_dir)
 651 {
 652         struct rb_node **p = &self->rb_node;
 653         struct rb_node *parent = NULL;
 654         struct machine *pos, *machine = malloc(sizeof(*machine));
 655
 656         if (!machine)
 657                 return NULL;
 658
 659         if (machine__init(machine, root_dir, pid) != 0) {
 660                 free(machine);
 661                 return NULL;
 662         }
 663
 664         while (*p != NULL) {
 665                 parent = *p;
 666                 pos = rb_entry(parent, struct machine, rb_node);
 667                 if (pid < pos->pid)
 668                         p = &(*p)->rb_left;
 669                 else
 670                         p = &(*p)->rb_right;
 671         }
 672
 673         rb_link_node(&machine->rb_node, parent, p);
 674         rb_insert_color(&machine->rb_node, self);
 675
 676         return machine;
 677 }
 678
 679 struct machine *machines__find(struct rb_root *self, pid_t pid)
 680 {
 681         struct rb_node **p = &self->rb_node;
 682         struct rb_node *parent = NULL;
 683         struct machine *machine;
 684         struct machine *default_machine = NULL;
 685
 686         while (*p != NULL) {
 687                 parent = *p;
 688                 machine = rb_entry(parent, struct machine, rb_node);
 689                 if (pid < machine->pid)
 690                         p = &(*p)->rb_left;
 691                 else if (pid > machine->pid)
 692                         p = &(*p)->rb_right;
 693                 else
 694                         return machine;
 695                 if (!machine->pid)
 696                         default_machine = machine;
 697         }
 698
 699         return default_machine;
 700 }
 701
 702 struct machine *machines__findnew(struct rb_root *self, pid_t pid)
 703 {
 704         char path[PATH_MAX];
 705         const char *root_dir = "";
 706         struct machine *machine = machines__find(self, pid);
 707
 708         if (machine && (machine->pid == pid))
 709                 goto out;
 710
 711         if ((pid != HOST_KERNEL_ID) &&
 712             (pid != DEFAULT_GUEST_KERNEL_ID) &&
 713             (symbol_conf.guestmount)) {
 714                 sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
 715                 if (access(path, R_OK)) {
 716                         static struct strlist *seen;
 717
 718                         if (!seen)
 719                                 seen = strlist__new(true, NULL);
 720
 721                         if (!strlist__has_entry(seen, path)) {
 722                                 pr_err("Can't access file %s\n", path);
 723                                 strlist__add(seen, path);
 724                         }
 725                         machine = NULL;
 726                         goto out;
 727                 }
 728                 root_dir = path;
 729         }
 730
 731         machine = machines__add(self, pid, root_dir);
 732
 733 out:
 734         return machine;
 735 }
 736
 737 void machines__process(struct rb_root *self, machine__process_t process, void *data)
 738 {
 739         struct rb_node *nd;
 740
 741         for (nd = rb_first(self); nd; nd = rb_next(nd)) {
 742                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 743                 process(pos, data);
 744         }
 745 }
 746
 747 char *machine__mmap_name(struct machine *self, char *bf, size_t size)
 748 {
 749         if (machine__is_host(self))
 750                 snprintf(bf, size, "[%s]", "kernel.kallsyms");
 751         else if (machine__is_default_guest(self))
 752                 snprintf(bf, size, "[%s]", "guest.kernel.kallsyms");
 753         else
 754                 snprintf(bf, size, "[%s.%d]", "guest.kernel.kallsyms", self->pid);
 755
 756         return bf;
 757 }
 758
 759 void machines__set_id_hdr_size(struct rb_root *machines, u16 id_hdr_size)
 760 {
 761         struct rb_node *node;
 762         struct machine *machine;
 763
 764         for (node = rb_first(machines); node; node = rb_next(node)) {
 765                 machine = rb_entry(node, struct machine, rb_node);
 766                 machine->id_hdr_size = id_hdr_size;
 767         }
 768
 769         return;
 770 }