tools/perf/util/machine.c

   1 #include "callchain.h"
   2 #include "debug.h"
   3 #include "event.h"
   4 #include "evsel.h"
   5 #include "hist.h"
   6 #include "machine.h"
   7 #include "map.h"
   8 #include "sort.h"
   9 #include "strlist.h"
  10 #include "thread.h"
  11 #include "vdso.h"
  12 #include <stdbool.h>
  13 #include <symbol/kallsyms.h>
  14 #include "unwind.h"
  15 #include "linux/hash.h"
  16
  17 static void dsos__init(struct dsos *dsos)
  18 {
  19         INIT_LIST_HEAD(&dsos->head);
  20         dsos->root = RB_ROOT;
  21 }
  22
  23 int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
  24 {
  25         map_groups__init(&machine->kmaps, machine);
  26         RB_CLEAR_NODE(&machine->rb_node);
  27         dsos__init(&machine->user_dsos);
  28         dsos__init(&machine->kernel_dsos);
  29
  30         machine->threads = RB_ROOT;
  31         INIT_LIST_HEAD(&machine->dead_threads);
  32         machine->last_match = NULL;
  33
  34         machine->vdso_info = NULL;
  35
  36         machine->pid = pid;
  37
  38         machine->symbol_filter = NULL;
  39         machine->id_hdr_size = 0;
  40         machine->comm_exec = false;
  41         machine->kernel_start = 0;
  42
  43         machine->root_dir = strdup(root_dir);
  44         if (machine->root_dir == NULL)
  45                 return -ENOMEM;
  46
  47         if (pid != HOST_KERNEL_ID) {
  48                 struct thread *thread = machine__findnew_thread(machine, -1,
  49                                                                 pid);
  50                 char comm[64];
  51
  52                 if (thread == NULL)
  53                         return -ENOMEM;
  54
  55                 snprintf(comm, sizeof(comm), "[guest/%d]", pid);
  56                 thread__set_comm(thread, comm, 0);
  57         }
  58
  59         machine->current_tid = NULL;
  60
  61         return 0;
  62 }
  63
  64 struct machine *machine__new_host(void)
  65 {
  66         struct machine *machine = malloc(sizeof(*machine));
  67
  68         if (machine != NULL) {
  69                 machine__init(machine, "", HOST_KERNEL_ID);
  70
  71                 if (machine__create_kernel_maps(machine) < 0)
  72                         goto out_delete;
  73         }
  74
  75         return machine;
  76 out_delete:
  77         free(machine);
  78         return NULL;
  79 }
  80
  81 static void dsos__delete(struct dsos *dsos)
  82 {
  83         struct dso *pos, *n;
  84
  85         list_for_each_entry_safe(pos, n, &dsos->head, node) {
  86                 RB_CLEAR_NODE(&pos->rb_node);
  87                 list_del(&pos->node);
  88                 dso__delete(pos);
  89         }
  90 }
  91
  92 void machine__delete_dead_threads(struct machine *machine)
  93 {
  94         struct thread *n, *t;
  95
  96         list_for_each_entry_safe(t, n, &machine->dead_threads, node) {
  97                 list_del(&t->node);
  98                 thread__delete(t);
  99         }
 100 }
 101
 102 void machine__delete_threads(struct machine *machine)
 103 {
 104         struct rb_node *nd = rb_first(&machine->threads);
 105
 106         while (nd) {
 107                 struct thread *t = rb_entry(nd, struct thread, rb_node);
 108
 109                 rb_erase(&t->rb_node, &machine->threads);
 110                 nd = rb_next(nd);
 111                 thread__delete(t);
 112         }
 113 }
 114
 115 void machine__exit(struct machine *machine)
 116 {
 117         map_groups__exit(&machine->kmaps);
 118         dsos__delete(&machine->user_dsos);
 119         dsos__delete(&machine->kernel_dsos);
 120         vdso__exit(machine);
 121         zfree(&machine->root_dir);
 122         zfree(&machine->current_tid);
 123 }
 124
 125 void machine__delete(struct machine *machine)
 126 {
 127         machine__exit(machine);
 128         free(machine);
 129 }
 130
 131 void machines__init(struct machines *machines)
 132 {
 133         machine__init(&machines->host, "", HOST_KERNEL_ID);
 134         machines->guests = RB_ROOT;
 135         machines->symbol_filter = NULL;
 136 }
 137
 138 void machines__exit(struct machines *machines)
 139 {
 140         machine__exit(&machines->host);
 141         /* XXX exit guest */
 142 }
 143
 144 struct machine *machines__add(struct machines *machines, pid_t pid,
 145                               const char *root_dir)
 146 {
 147         struct rb_node **p = &machines->guests.rb_node;
 148         struct rb_node *parent = NULL;
 149         struct machine *pos, *machine = malloc(sizeof(*machine));
 150
 151         if (machine == NULL)
 152                 return NULL;
 153
 154         if (machine__init(machine, root_dir, pid) != 0) {
 155                 free(machine);
 156                 return NULL;
 157         }
 158
 159         machine->symbol_filter = machines->symbol_filter;
 160
 161         while (*p != NULL) {
 162                 parent = *p;
 163                 pos = rb_entry(parent, struct machine, rb_node);
 164                 if (pid < pos->pid)
 165                         p = &(*p)->rb_left;
 166                 else
 167                         p = &(*p)->rb_right;
 168         }
 169
 170         rb_link_node(&machine->rb_node, parent, p);
 171         rb_insert_color(&machine->rb_node, &machines->guests);
 172
 173         return machine;
 174 }
 175
 176 void machines__set_symbol_filter(struct machines *machines,
 177                                  symbol_filter_t symbol_filter)
 178 {
 179         struct rb_node *nd;
 180
 181         machines->symbol_filter = symbol_filter;
 182         machines->host.symbol_filter = symbol_filter;
 183
 184         for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
 185                 struct machine *machine = rb_entry(nd, struct machine, rb_node);
 186
 187                 machine->symbol_filter = symbol_filter;
 188         }
 189 }
 190
 191 void machines__set_comm_exec(struct machines *machines, bool comm_exec)
 192 {
 193         struct rb_node *nd;
 194
 195         machines->host.comm_exec = comm_exec;
 196
 197         for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
 198                 struct machine *machine = rb_entry(nd, struct machine, rb_node);
 199
 200                 machine->comm_exec = comm_exec;
 201         }
 202 }
 203
 204 struct machine *machines__find(struct machines *machines, pid_t pid)
 205 {
 206         struct rb_node **p = &machines->guests.rb_node;
 207         struct rb_node *parent = NULL;
 208         struct machine *machine;
 209         struct machine *default_machine = NULL;
 210
 211         if (pid == HOST_KERNEL_ID)
 212                 return &machines->host;
 213
 214         while (*p != NULL) {
 215                 parent = *p;
 216                 machine = rb_entry(parent, struct machine, rb_node);
 217                 if (pid < machine->pid)
 218                         p = &(*p)->rb_left;
 219                 else if (pid > machine->pid)
 220                         p = &(*p)->rb_right;
 221                 else
 222                         return machine;
 223                 if (!machine->pid)
 224                         default_machine = machine;
 225         }
 226
 227         return default_machine;
 228 }
 229
 230 struct machine *machines__findnew(struct machines *machines, pid_t pid)
 231 {
 232         char path[PATH_MAX];
 233         const char *root_dir = "";
 234         struct machine *machine = machines__find(machines, pid);
 235
 236         if (machine && (machine->pid == pid))
 237                 goto out;
 238
 239         if ((pid != HOST_KERNEL_ID) &&
 240             (pid != DEFAULT_GUEST_KERNEL_ID) &&
 241             (symbol_conf.guestmount)) {
 242                 sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
 243                 if (access(path, R_OK)) {
 244                         static struct strlist *seen;
 245
 246                         if (!seen)
 247                                 seen = strlist__new(true, NULL);
 248
 249                         if (!strlist__has_entry(seen, path)) {
 250                                 pr_err("Can't access file %s\n", path);
 251                                 strlist__add(seen, path);
 252                         }
 253                         machine = NULL;
 254                         goto out;
 255                 }
 256                 root_dir = path;
 257         }
 258
 259         machine = machines__add(machines, pid, root_dir);
 260 out:
 261         return machine;
 262 }
 263
 264 void machines__process_guests(struct machines *machines,
 265                               machine__process_t process, void *data)
 266 {
 267         struct rb_node *nd;
 268
 269         for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
 270                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 271                 process(pos, data);
 272         }
 273 }
 274
 275 char *machine__mmap_name(struct machine *machine, char *bf, size_t size)
 276 {
 277         if (machine__is_host(machine))
 278                 snprintf(bf, size, "[%s]", "kernel.kallsyms");
 279         else if (machine__is_default_guest(machine))
 280                 snprintf(bf, size, "[%s]", "guest.kernel.kallsyms");
 281         else {
 282                 snprintf(bf, size, "[%s.%d]", "guest.kernel.kallsyms",
 283                          machine->pid);
 284         }
 285
 286         return bf;
 287 }
 288
 289 void machines__set_id_hdr_size(struct machines *machines, u16 id_hdr_size)
 290 {
 291         struct rb_node *node;
 292         struct machine *machine;
 293
 294         machines->host.id_hdr_size = id_hdr_size;
 295
 296         for (node = rb_first(&machines->guests); node; node = rb_next(node)) {
 297                 machine = rb_entry(node, struct machine, rb_node);
 298                 machine->id_hdr_size = id_hdr_size;
 299         }
 300
 301         return;
 302 }
 303
 304 static void machine__update_thread_pid(struct machine *machine,
 305                                        struct thread *th, pid_t pid)
 306 {
 307         struct thread *leader;
 308
 309         if (pid == th->pid_ || pid == -1 || th->pid_ != -1)
 310                 return;
 311
 312         th->pid_ = pid;
 313
 314         if (th->pid_ == th->tid)
 315                 return;
 316
 317         leader = machine__findnew_thread(machine, th->pid_, th->pid_);
 318         if (!leader)
 319                 goto out_err;
 320
 321         if (!leader->mg)
 322                 leader->mg = map_groups__new(machine);
 323
 324         if (!leader->mg)
 325                 goto out_err;
 326
 327         if (th->mg == leader->mg)
 328                 return;
 329
 330         if (th->mg) {
 331                 /*
 332                  * Maps are created from MMAP events which provide the pid and
 333                  * tid.  Consequently there never should be any maps on a thread
 334                  * with an unknown pid.  Just print an error if there are.
 335                  */
 336                 if (!map_groups__empty(th->mg))
 337                         pr_err("Discarding thread maps for %d:%d\n",
 338                                th->pid_, th->tid);
 339                 map_groups__delete(th->mg);
 340         }
 341
 342         th->mg = map_groups__get(leader->mg);
 343
 344         return;
 345
 346 out_err:
 347         pr_err("Failed to join map groups for %d:%d\n", th->pid_, th->tid);
 348 }
 349
 350 static struct thread *__machine__findnew_thread(struct machine *machine,
 351                                                 pid_t pid, pid_t tid,
 352                                                 bool create)
 353 {
 354         struct rb_node **p = &machine->threads.rb_node;
 355         struct rb_node *parent = NULL;
 356         struct thread *th;
 357
 358         /*
 359          * Front-end cache - TID lookups come in blocks,
 360          * so most of the time we dont have to look up
 361          * the full rbtree:
 362          */
 363         th = machine->last_match;
 364         if (th && th->tid == tid) {
 365                 machine__update_thread_pid(machine, th, pid);
 366                 return th;
 367         }
 368
 369         while (*p != NULL) {
 370                 parent = *p;
 371                 th = rb_entry(parent, struct thread, rb_node);
 372
 373                 if (th->tid == tid) {
 374                         machine->last_match = th;
 375                         machine__update_thread_pid(machine, th, pid);
 376                         return th;
 377                 }
 378
 379                 if (tid < th->tid)
 380                         p = &(*p)->rb_left;
 381                 else
 382                         p = &(*p)->rb_right;
 383         }
 384
 385         if (!create)
 386                 return NULL;
 387
 388         th = thread__new(pid, tid);
 389         if (th != NULL) {
 390                 rb_link_node(&th->rb_node, parent, p);
 391                 rb_insert_color(&th->rb_node, &machine->threads);
 392                 machine->last_match = th;
 393
 394                 /*
 395                  * We have to initialize map_groups separately
 396                  * after rb tree is updated.
 397                  *
 398                  * The reason is that we call machine__findnew_thread
 399                  * within thread__init_map_groups to find the thread
 400                  * leader and that would screwed the rb tree.
 401                  */
 402                 if (thread__init_map_groups(th, machine)) {
 403                         thread__delete(th);
 404                         return NULL;
 405                 }
 406         }
 407
 408         return th;
 409 }
 410
 411 struct thread *machine__findnew_thread(struct machine *machine, pid_t pid,
 412                                        pid_t tid)
 413 {
 414         return __machine__findnew_thread(machine, pid, tid, true);
 415 }
 416
 417 struct thread *machine__find_thread(struct machine *machine, pid_t pid,
 418                                     pid_t tid)
 419 {
 420         return __machine__findnew_thread(machine, pid, tid, false);
 421 }
 422
 423 struct comm *machine__thread_exec_comm(struct machine *machine,
 424                                        struct thread *thread)
 425 {
 426         if (machine->comm_exec)
 427                 return thread__exec_comm(thread);
 428         else
 429                 return thread__comm(thread);
 430 }
 431
 432 int machine__process_comm_event(struct machine *machine, union perf_event *event,
 433                                 struct perf_sample *sample)
 434 {
 435         struct thread *thread = machine__findnew_thread(machine,
 436                                                         event->comm.pid,
 437                                                         event->comm.tid);
 438         bool exec = event->header.misc & PERF_RECORD_MISC_COMM_EXEC;
 439
 440         if (exec)
 441                 machine->comm_exec = true;
 442
 443         if (dump_trace)
 444                 perf_event__fprintf_comm(event, stdout);
 445
 446         if (thread == NULL ||
 447             __thread__set_comm(thread, event->comm.comm, sample->time, exec)) {
 448                 dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
 449                 return -1;
 450         }
 451
 452         return 0;
 453 }
 454
 455 int machine__process_lost_event(struct machine *machine __maybe_unused,
 456                                 union perf_event *event, struct perf_sample *sample __maybe_unused)
 457 {
 458         dump_printf(": id:%" PRIu64 ": lost:%" PRIu64 "\n",
 459                     event->lost.id, event->lost.lost);
 460         return 0;
 461 }
 462
 463 struct map *machine__new_module(struct machine *machine, u64 start,
 464                                 const char *filename)
 465 {
 466         struct map *map;
 467         struct dso *dso = __dsos__findnew(&machine->kernel_dsos, filename);
 468         bool compressed;
 469
 470         if (dso == NULL)
 471                 return NULL;
 472
 473         map = map__new2(start, dso, MAP__FUNCTION);
 474         if (map == NULL)
 475                 return NULL;
 476
 477         if (machine__is_host(machine))
 478                 dso->symtab_type = DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE;
 479         else
 480                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
 481
 482         /* _KMODULE_COMP should be next to _KMODULE */
 483         if (is_kernel_module(filename, &compressed) && compressed)
 484                 dso->symtab_type++;
 485
 486         map_groups__insert(&machine->kmaps, map);
 487         return map;
 488 }
 489
 490 size_t machines__fprintf_dsos(struct machines *machines, FILE *fp)
 491 {
 492         struct rb_node *nd;
 493         size_t ret = __dsos__fprintf(&machines->host.kernel_dsos.head, fp) +
 494                      __dsos__fprintf(&machines->host.user_dsos.head, fp);
 495
 496         for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
 497                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 498                 ret += __dsos__fprintf(&pos->kernel_dsos.head, fp);
 499                 ret += __dsos__fprintf(&pos->user_dsos.head, fp);
 500         }
 501
 502         return ret;
 503 }
 504
 505 size_t machine__fprintf_dsos_buildid(struct machine *m, FILE *fp,
 506                                      bool (skip)(struct dso *dso, int parm), int parm)
 507 {
 508         return __dsos__fprintf_buildid(&m->kernel_dsos.head, fp, skip, parm) +
 509                __dsos__fprintf_buildid(&m->user_dsos.head, fp, skip, parm);
 510 }
 511
 512 size_t machines__fprintf_dsos_buildid(struct machines *machines, FILE *fp,
 513                                      bool (skip)(struct dso *dso, int parm), int parm)
 514 {
 515         struct rb_node *nd;
 516         size_t ret = machine__fprintf_dsos_buildid(&machines->host, fp, skip, parm);
 517
 518         for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
 519                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 520                 ret += machine__fprintf_dsos_buildid(pos, fp, skip, parm);
 521         }
 522         return ret;
 523 }
 524
 525 size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp)
 526 {
 527         int i;
 528         size_t printed = 0;
 529         struct dso *kdso = machine->vmlinux_maps[MAP__FUNCTION]->dso;
 530
 531         if (kdso->has_build_id) {
 532                 char filename[PATH_MAX];
 533                 if (dso__build_id_filename(kdso, filename, sizeof(filename)))
 534                         printed += fprintf(fp, "[0] %s\n", filename);
 535         }
 536
 537         for (i = 0; i < vmlinux_path__nr_entries; ++i)
 538                 printed += fprintf(fp, "[%d] %s\n",
 539                                    i + kdso->has_build_id, vmlinux_path[i]);
 540
 541         return printed;
 542 }
 543
 544 size_t machine__fprintf(struct machine *machine, FILE *fp)
 545 {
 546         size_t ret = 0;
 547         struct rb_node *nd;
 548
 549         for (nd = rb_first(&machine->threads); nd; nd = rb_next(nd)) {
 550                 struct thread *pos = rb_entry(nd, struct thread, rb_node);
 551
 552                 ret += thread__fprintf(pos, fp);
 553         }
 554
 555         return ret;
 556 }
 557
 558 static struct dso *machine__get_kernel(struct machine *machine)
 559 {
 560         const char *vmlinux_name = NULL;
 561         struct dso *kernel;
 562
 563         if (machine__is_host(machine)) {
 564                 vmlinux_name = symbol_conf.vmlinux_name;
 565                 if (!vmlinux_name)
 566                         vmlinux_name = "[kernel.kallsyms]";
 567
 568                 kernel = dso__kernel_findnew(machine, vmlinux_name,
 569                                              "[kernel]",
 570                                              DSO_TYPE_KERNEL);
 571         } else {
 572                 char bf[PATH_MAX];
 573
 574                 if (machine__is_default_guest(machine))
 575                         vmlinux_name = symbol_conf.default_guest_vmlinux_name;
 576                 if (!vmlinux_name)
 577                         vmlinux_name = machine__mmap_name(machine, bf,
 578                                                           sizeof(bf));
 579
 580                 kernel = dso__kernel_findnew(machine, vmlinux_name,
 581                                              "[guest.kernel]",
 582                                              DSO_TYPE_GUEST_KERNEL);
 583         }
 584
 585         if (kernel != NULL && (!kernel->has_build_id))
 586                 dso__read_running_kernel_build_id(kernel, machine);
 587
 588         return kernel;
 589 }
 590
 591 struct process_args {
 592         u64 start;
 593 };
 594
 595 static void machine__get_kallsyms_filename(struct machine *machine, char *buf,
 596                                            size_t bufsz)
 597 {
 598         if (machine__is_default_guest(machine))
 599                 scnprintf(buf, bufsz, "%s", symbol_conf.default_guest_kallsyms);
 600         else
 601                 scnprintf(buf, bufsz, "%s/proc/kallsyms", machine->root_dir);
 602 }
 603
 604 const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL};
 605
 606 /* Figure out the start address of kernel map from /proc/kallsyms.
 607  * Returns the name of the start symbol in *symbol_name. Pass in NULL as
 608  * symbol_name if it's not that important.
 609  */
 610 static u64 machine__get_running_kernel_start(struct machine *machine,
 611                                              const char **symbol_name)
 612 {
 613         char filename[PATH_MAX];
 614         int i;
 615         const char *name;
 616         u64 addr = 0;
 617
 618         machine__get_kallsyms_filename(machine, filename, PATH_MAX);
 619
 620         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
 621                 return 0;
 622
 623         for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
 624                 addr = kallsyms__get_function_start(filename, name);
 625                 if (addr)
 626                         break;
 627         }
 628
 629         if (symbol_name)
 630                 *symbol_name = name;
 631
 632         return addr;
 633 }
 634
 635 int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
 636 {
 637         enum map_type type;
 638         u64 start = machine__get_running_kernel_start(machine, NULL);
 639
 640         for (type = 0; type < MAP__NR_TYPES; ++type) {
 641                 struct kmap *kmap;
 642
 643                 machine->vmlinux_maps[type] = map__new2(start, kernel, type);
 644                 if (machine->vmlinux_maps[type] == NULL)
 645                         return -1;
 646
 647                 machine->vmlinux_maps[type]->map_ip =
 648                         machine->vmlinux_maps[type]->unmap_ip =
 649                                 identity__map_ip;
 650                 kmap = map__kmap(machine->vmlinux_maps[type]);
 651                 kmap->kmaps = &machine->kmaps;
 652                 map_groups__insert(&machine->kmaps,
 653                                    machine->vmlinux_maps[type]);
 654         }
 655
 656         return 0;
 657 }
 658
 659 void machine__destroy_kernel_maps(struct machine *machine)
 660 {
 661         enum map_type type;
 662
 663         for (type = 0; type < MAP__NR_TYPES; ++type) {
 664                 struct kmap *kmap;
 665
 666                 if (machine->vmlinux_maps[type] == NULL)
 667                         continue;
 668
 669                 kmap = map__kmap(machine->vmlinux_maps[type]);
 670                 map_groups__remove(&machine->kmaps,
 671                                    machine->vmlinux_maps[type]);
 672                 if (kmap->ref_reloc_sym) {
 673                         /*
 674                          * ref_reloc_sym is shared among all maps, so free just
 675                          * on one of them.
 676                          */
 677                         if (type == MAP__FUNCTION) {
 678                                 zfree((char **)&kmap->ref_reloc_sym->name);
 679                                 zfree(&kmap->ref_reloc_sym);
 680                         } else
 681                                 kmap->ref_reloc_sym = NULL;
 682                 }
 683
 684                 map__delete(machine->vmlinux_maps[type]);
 685                 machine->vmlinux_maps[type] = NULL;
 686         }
 687 }
 688
 689 int machines__create_guest_kernel_maps(struct machines *machines)
 690 {
 691         int ret = 0;
 692         struct dirent **namelist = NULL;
 693         int i, items = 0;
 694         char path[PATH_MAX];
 695         pid_t pid;
 696         char *endp;
 697
 698         if (symbol_conf.default_guest_vmlinux_name ||
 699             symbol_conf.default_guest_modules ||
 700             symbol_conf.default_guest_kallsyms) {
 701                 machines__create_kernel_maps(machines, DEFAULT_GUEST_KERNEL_ID);
 702         }
 703
 704         if (symbol_conf.guestmount) {
 705                 items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
 706                 if (items <= 0)
 707                         return -ENOENT;
 708                 for (i = 0; i < items; i++) {
 709                         if (!isdigit(namelist[i]->d_name[0])) {
 710                                 /* Filter out . and .. */
 711                                 continue;
 712                         }
 713                         pid = (pid_t)strtol(namelist[i]->d_name, &endp, 10);
 714                         if ((*endp != '\0') ||
 715                             (endp == namelist[i]->d_name) ||
 716                             (errno == ERANGE)) {
 717                                 pr_debug("invalid directory (%s). Skipping.\n",
 718                                          namelist[i]->d_name);
 719                                 continue;
 720                         }
 721                         sprintf(path, "%s/%s/proc/kallsyms",
 722                                 symbol_conf.guestmount,
 723                                 namelist[i]->d_name);
 724                         ret = access(path, R_OK);
 725                         if (ret) {
 726                                 pr_debug("Can't access file %s\n", path);
 727                                 goto failure;
 728                         }
 729                         machines__create_kernel_maps(machines, pid);
 730                 }
 731 failure:
 732                 free(namelist);
 733         }
 734
 735         return ret;
 736 }
 737
 738 void machines__destroy_kernel_maps(struct machines *machines)
 739 {
 740         struct rb_node *next = rb_first(&machines->guests);
 741
 742         machine__destroy_kernel_maps(&machines->host);
 743
 744         while (next) {
 745                 struct machine *pos = rb_entry(next, struct machine, rb_node);
 746
 747                 next = rb_next(&pos->rb_node);
 748                 rb_erase(&pos->rb_node, &machines->guests);
 749                 machine__delete(pos);
 750         }
 751 }
 752
 753 int machines__create_kernel_maps(struct machines *machines, pid_t pid)
 754 {
 755         struct machine *machine = machines__findnew(machines, pid);
 756
 757         if (machine == NULL)
 758                 return -1;
 759
 760         return machine__create_kernel_maps(machine);
 761 }
 762
 763 int machine__load_kallsyms(struct machine *machine, const char *filename,
 764                            enum map_type type, symbol_filter_t filter)
 765 {
 766         struct map *map = machine->vmlinux_maps[type];
 767         int ret = dso__load_kallsyms(map->dso, filename, map, filter);
 768
 769         if (ret > 0) {
 770                 dso__set_loaded(map->dso, type);
 771                 /*
 772                  * Since /proc/kallsyms will have multiple sessions for the
 773                  * kernel, with modules between them, fixup the end of all
 774                  * sections.
 775                  */
 776                 __map_groups__fixup_end(&machine->kmaps, type);
 777         }
 778
 779         return ret;
 780 }
 781
 782 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,
 783                                symbol_filter_t filter)
 784 {
 785         struct map *map = machine->vmlinux_maps[type];
 786         int ret = dso__load_vmlinux_path(map->dso, map, filter);
 787
 788         if (ret > 0)
 789                 dso__set_loaded(map->dso, type);
 790
 791         return ret;
 792 }
 793
 794 static void map_groups__fixup_end(struct map_groups *mg)
 795 {
 796         int i;
 797         for (i = 0; i < MAP__NR_TYPES; ++i)
 798                 __map_groups__fixup_end(mg, i);
 799 }
 800
 801 static char *get_kernel_version(const char *root_dir)
 802 {
 803         char version[PATH_MAX];
 804         FILE *file;
 805         char *name, *tmp;
 806         const char *prefix = "Linux version ";
 807
 808         sprintf(version, "%s/proc/version", root_dir);
 809         file = fopen(version, "r");
 810         if (!file)
 811                 return NULL;
 812
 813         version[0] = '\0';
 814         tmp = fgets(version, sizeof(version), file);
 815         fclose(file);
 816
 817         name = strstr(version, prefix);
 818         if (!name)
 819                 return NULL;
 820         name += strlen(prefix);
 821         tmp = strchr(name, ' ');
 822         if (tmp)
 823                 *tmp = '\0';
 824
 825         return strdup(name);
 826 }
 827
 828 static int map_groups__set_modules_path_dir(struct map_groups *mg,
 829                                 const char *dir_name, int depth)
 830 {
 831         struct dirent *dent;
 832         DIR *dir = opendir(dir_name);
 833         int ret = 0;
 834
 835         if (!dir) {
 836                 pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
 837                 return -1;
 838         }
 839
 840         while ((dent = readdir(dir)) != NULL) {
 841                 char path[PATH_MAX];
 842                 struct stat st;
 843
 844                 /*sshfs might return bad dent->d_type, so we have to stat*/
 845                 snprintf(path, sizeof(path), "%s/%s", dir_name, dent->d_name);
 846                 if (stat(path, &st))
 847                         continue;
 848
 849                 if (S_ISDIR(st.st_mode)) {
 850                         if (!strcmp(dent->d_name, ".") ||
 851                             !strcmp(dent->d_name, ".."))
 852                                 continue;
 853
 854                         /* Do not follow top-level source and build symlinks */
 855                         if (depth == 0) {
 856                                 if (!strcmp(dent->d_name, "source") ||
 857                                     !strcmp(dent->d_name, "build"))
 858                                         continue;
 859                         }
 860
 861                         ret = map_groups__set_modules_path_dir(mg, path,
 862                                                                depth + 1);
 863                         if (ret < 0)
 864                                 goto out;
 865                 } else {
 866                         char *dot = strrchr(dent->d_name, '.'),
 867                              dso_name[PATH_MAX];
 868                         struct map *map;
 869                         char *long_name;
 870
 871                         if (dot == NULL)
 872                                 continue;
 873
 874                         /* On some system, modules are compressed like .ko.gz */
 875                         if (is_supported_compression(dot + 1) &&
 876                             is_kmodule_extension(dot - 2))
 877                                 dot -= 3;
 878
 879                         snprintf(dso_name, sizeof(dso_name), "[%.*s]",
 880                                  (int)(dot - dent->d_name), dent->d_name);
 881
 882                         strxfrchar(dso_name, '-', '_');
 883                         map = map_groups__find_by_name(mg, MAP__FUNCTION,
 884                                                        dso_name);
 885                         if (map == NULL)
 886                                 continue;
 887
 888                         long_name = strdup(path);
 889                         if (long_name == NULL) {
 890                                 ret = -1;
 891                                 goto out;
 892                         }
 893                         dso__set_long_name(map->dso, long_name, true);
 894                         dso__kernel_module_get_build_id(map->dso, "");
 895                 }
 896         }
 897
 898 out:
 899         closedir(dir);
 900         return ret;
 901 }
 902
 903 static int machine__set_modules_path(struct machine *machine)
 904 {
 905         char *version;
 906         char modules_path[PATH_MAX];
 907
 908         version = get_kernel_version(machine->root_dir);
 909         if (!version)
 910                 return -1;
 911
 912         snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s",
 913                  machine->root_dir, version);
 914         free(version);
 915
 916         return map_groups__set_modules_path_dir(&machine->kmaps, modules_path, 0);
 917 }
 918
 919 static int machine__create_module(void *arg, const char *name, u64 start)
 920 {
 921         struct machine *machine = arg;
 922         struct map *map;
 923
 924         map = machine__new_module(machine, start, name);
 925         if (map == NULL)
 926                 return -1;
 927
 928         dso__kernel_module_get_build_id(map->dso, machine->root_dir);
 929
 930         return 0;
 931 }
 932
 933 static int machine__create_modules(struct machine *machine)
 934 {
 935         const char *modules;
 936         char path[PATH_MAX];
 937
 938         if (machine__is_default_guest(machine)) {
 939                 modules = symbol_conf.default_guest_modules;
 940         } else {
 941                 snprintf(path, PATH_MAX, "%s/proc/modules", machine->root_dir);
 942                 modules = path;
 943         }
 944
 945         if (symbol__restricted_filename(modules, "/proc/modules"))
 946                 return -1;
 947
 948         if (modules__parse(modules, machine, machine__create_module))
 949                 return -1;
 950
 951         if (!machine__set_modules_path(machine))
 952                 return 0;
 953
 954         pr_debug("Problems setting modules path maps, continuing anyway...\n");
 955
 956         return 0;
 957 }
 958
 959 int machine__create_kernel_maps(struct machine *machine)
 960 {
 961         struct dso *kernel = machine__get_kernel(machine);
 962         const char *name;
 963         u64 addr = machine__get_running_kernel_start(machine, &name);
 964         if (!addr)
 965                 return -1;
 966
 967         if (kernel == NULL ||
 968             __machine__create_kernel_maps(machine, kernel) < 0)
 969                 return -1;
 970
 971         if (symbol_conf.use_modules && machine__create_modules(machine) < 0) {
 972                 if (machine__is_host(machine))
 973                         pr_debug("Problems creating module maps, "
 974                                  "continuing anyway...\n");
 975                 else
 976                         pr_debug("Problems creating module maps for guest %d, "
 977                                  "continuing anyway...\n", machine->pid);
 978         }
 979
 980         /*
 981          * Now that we have all the maps created, just set the ->end of them:
 982          */
 983         map_groups__fixup_end(&machine->kmaps);
 984
 985         if (maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name,
 986                                              addr)) {
 987                 machine__destroy_kernel_maps(machine);
 988                 return -1;
 989         }
 990
 991         return 0;
 992 }
 993
 994 static void machine__set_kernel_mmap_len(struct machine *machine,
 995                                          union perf_event *event)
 996 {
 997         int i;
 998
 999         for (i = 0; i < MAP__NR_TYPES; i++) {
1000                 machine->vmlinux_maps[i]->start = event->mmap.start;
1001                 machine->vmlinux_maps[i]->end   = (event->mmap.start +
1002                                                    event->mmap.len);
1003                 /*
1004                  * Be a bit paranoid here, some perf.data file came with
1005                  * a zero sized synthesized MMAP event for the kernel.
1006                  */
1007                 if (machine->vmlinux_maps[i]->end == 0)
1008                         machine->vmlinux_maps[i]->end = ~0ULL;
1009         }
1010 }
1011
1012 static bool machine__uses_kcore(struct machine *machine)
1013 {
1014         struct dso *dso;
1015
1016         list_for_each_entry(dso, &machine->kernel_dsos.head, node) {
1017                 if (dso__is_kcore(dso))
1018                         return true;
1019         }
1020
1021         return false;
1022 }
1023
1024 static int machine__process_kernel_mmap_event(struct machine *machine,
1025                                               union perf_event *event)
1026 {
1027         struct map *map;
1028         char kmmap_prefix[PATH_MAX];
1029         enum dso_kernel_type kernel_type;
1030         bool is_kernel_mmap;
1031
1032         /* If we have maps from kcore then we do not need or want any others */
1033         if (machine__uses_kcore(machine))
1034                 return 0;
1035
1036         machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
1037         if (machine__is_host(machine))
1038                 kernel_type = DSO_TYPE_KERNEL;
1039         else
1040                 kernel_type = DSO_TYPE_GUEST_KERNEL;
1041
1042         is_kernel_mmap = memcmp(event->mmap.filename,
1043                                 kmmap_prefix,
1044                                 strlen(kmmap_prefix) - 1) == 0;
1045         if (event->mmap.filename[0] == '/' ||
1046             (!is_kernel_mmap && event->mmap.filename[0] == '[')) {
1047
1048                 char short_module_name[1024];
1049                 char *name, *dot;
1050
1051                 if (event->mmap.filename[0] == '/') {
1052                         name = strrchr(event->mmap.filename, '/');
1053                         if (name == NULL)
1054                                 goto out_problem;
1055
1056                         ++name; /* skip / */
1057                         dot = strrchr(name, '.');
1058                         if (dot == NULL)
1059                                 goto out_problem;
1060                         /* On some system, modules are compressed like .ko.gz */
1061                         if (is_supported_compression(dot + 1))
1062                                 dot -= 3;
1063                         if (!is_kmodule_extension(dot + 1))
1064                                 goto out_problem;
1065                         snprintf(short_module_name, sizeof(short_module_name),
1066                                         "[%.*s]", (int)(dot - name), name);
1067                         strxfrchar(short_module_name, '-', '_');
1068                 } else
1069                         strcpy(short_module_name, event->mmap.filename);
1070
1071                 map = machine__new_module(machine, event->mmap.start,
1072                                           event->mmap.filename);
1073                 if (map == NULL)
1074                         goto out_problem;
1075
1076                 name = strdup(short_module_name);
1077                 if (name == NULL)
1078                         goto out_problem;
1079
1080                 dso__set_short_name(map->dso, name, true);
1081                 map->end = map->start + event->mmap.len;
1082         } else if (is_kernel_mmap) {
1083                 const char *symbol_name = (event->mmap.filename +
1084                                 strlen(kmmap_prefix));
1085                 /*
1086                  * Should be there already, from the build-id table in
1087                  * the header.
1088                  */
1089                 struct dso *kernel = NULL;
1090                 struct dso *dso;
1091
1092                 list_for_each_entry(dso, &machine->kernel_dsos.head, node) {
1093                         if (is_kernel_module(dso->long_name, NULL))
1094                                 continue;
1095
1096                         kernel = dso;
1097                         break;
1098                 }
1099
1100                 if (kernel == NULL)
1101                         kernel = __dsos__findnew(&machine->kernel_dsos,
1102                                                  kmmap_prefix);
1103                 if (kernel == NULL)
1104                         goto out_problem;
1105
1106                 kernel->kernel = kernel_type;
1107                 if (__machine__create_kernel_maps(machine, kernel) < 0)
1108                         goto out_problem;
1109
1110                 if (strstr(kernel->long_name, "vmlinux"))
1111                         dso__set_short_name(kernel, "[kernel.vmlinux]", false);
1112
1113                 machine__set_kernel_mmap_len(machine, event);
1114
1115                 /*
1116                  * Avoid using a zero address (kptr_restrict) for the ref reloc
1117                  * symbol. Effectively having zero here means that at record
1118                  * time /proc/sys/kernel/kptr_restrict was non zero.
1119                  */
1120                 if (event->mmap.pgoff != 0) {
1121                         maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
1122                                                          symbol_name,
1123                                                          event->mmap.pgoff);
1124                 }
1125
1126                 if (machine__is_default_guest(machine)) {
1127                         /*
1128                          * preload dso of guest kernel and modules
1129                          */
1130                         dso__load(kernel, machine->vmlinux_maps[MAP__FUNCTION],
1131                                   NULL);
1132                 }
1133         }
1134         return 0;
1135 out_problem:
1136         return -1;
1137 }
1138
1139 int machine__process_mmap2_event(struct machine *machine,
1140                                  union perf_event *event,
1141                                  struct perf_sample *sample __maybe_unused)
1142 {
1143         u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
1144         struct thread *thread;
1145         struct map *map;
1146         enum map_type type;
1147         int ret = 0;
1148
1149         if (dump_trace)
1150                 perf_event__fprintf_mmap2(event, stdout);
1151
1152         if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
1153             cpumode == PERF_RECORD_MISC_KERNEL) {
1154                 ret = machine__process_kernel_mmap_event(machine, event);
1155                 if (ret < 0)
1156                         goto out_problem;
1157                 return 0;
1158         }
1159
1160         thread = machine__findnew_thread(machine, event->mmap2.pid,
1161                                         event->mmap2.tid);
1162         if (thread == NULL)
1163                 goto out_problem;
1164
1165         if (event->header.misc & PERF_RECORD_MISC_MMAP_DATA)
1166                 type = MAP__VARIABLE;
1167         else
1168                 type = MAP__FUNCTION;
1169
1170         map = map__new(machine, event->mmap2.start,
1171                         event->mmap2.len, event->mmap2.pgoff,
1172                         event->mmap2.pid, event->mmap2.maj,
1173                         event->mmap2.min, event->mmap2.ino,
1174                         event->mmap2.ino_generation,
1175                         event->mmap2.prot,
1176                         event->mmap2.flags,
1177                         event->mmap2.filename, type, thread);
1178
1179         if (map == NULL)
1180                 goto out_problem;
1181
1182         thread__insert_map(thread, map);
1183         return 0;
1184
1185 out_problem:
1186         dump_printf("problem processing PERF_RECORD_MMAP2, skipping event.\n");
1187         return 0;
1188 }
1189
1190 int machine__process_mmap_event(struct machine *machine, union perf_event *event,
1191                                 struct perf_sample *sample __maybe_unused)
1192 {
1193         u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
1194         struct thread *thread;
1195         struct map *map;
1196         enum map_type type;
1197         int ret = 0;
1198
1199         if (dump_trace)
1200                 perf_event__fprintf_mmap(event, stdout);
1201
1202         if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
1203             cpumode == PERF_RECORD_MISC_KERNEL) {
1204                 ret = machine__process_kernel_mmap_event(machine, event);
1205                 if (ret < 0)
1206                         goto out_problem;
1207                 return 0;
1208         }
1209
1210         thread = machine__findnew_thread(machine, event->mmap.pid,
1211                                          event->mmap.tid);
1212         if (thread == NULL)
1213                 goto out_problem;
1214
1215         if (event->header.misc & PERF_RECORD_MISC_MMAP_DATA)
1216                 type = MAP__VARIABLE;
1217         else
1218                 type = MAP__FUNCTION;
1219
1220         map = map__new(machine, event->mmap.start,
1221                         event->mmap.len, event->mmap.pgoff,
1222                         event->mmap.pid, 0, 0, 0, 0, 0, 0,
1223                         event->mmap.filename,
1224                         type, thread);
1225
1226         if (map == NULL)
1227                 goto out_problem;
1228
1229         thread__insert_map(thread, map);
1230         return 0;
1231
1232 out_problem:
1233         dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
1234         return 0;
1235 }
1236
1237 static void machine__remove_thread(struct machine *machine, struct thread *th)
1238 {
1239         machine->last_match = NULL;
1240         rb_erase(&th->rb_node, &machine->threads);
1241         /*
1242          * We may have references to this thread, for instance in some hist_entry
1243          * instances, so just move them to a separate list.
1244          */
1245         list_add_tail(&th->node, &machine->dead_threads);
1246 }
1247
1248 int machine__process_fork_event(struct machine *machine, union perf_event *event,
1249                                 struct perf_sample *sample)
1250 {
1251         struct thread *thread = machine__find_thread(machine,
1252                                                      event->fork.pid,
1253                                                      event->fork.tid);
1254         struct thread *parent = machine__findnew_thread(machine,
1255                                                         event->fork.ppid,
1256                                                         event->fork.ptid);
1257
1258         /* if a thread currently exists for the thread id remove it */
1259         if (thread != NULL)
1260                 machine__remove_thread(machine, thread);
1261
1262         thread = machine__findnew_thread(machine, event->fork.pid,
1263                                          event->fork.tid);
1264         if (dump_trace)
1265                 perf_event__fprintf_task(event, stdout);
1266
1267         if (thread == NULL || parent == NULL ||
1268             thread__fork(thread, parent, sample->time) < 0) {
1269                 dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
1270                 return -1;
1271         }
1272
1273         return 0;
1274 }
1275
1276 int machine__process_exit_event(struct machine *machine, union perf_event *event,
1277                                 struct perf_sample *sample __maybe_unused)
1278 {
1279         struct thread *thread = machine__find_thread(machine,
1280                                                      event->fork.pid,
1281                                                      event->fork.tid);
1282
1283         if (dump_trace)
1284                 perf_event__fprintf_task(event, stdout);
1285
1286         if (thread != NULL)
1287                 thread__exited(thread);
1288
1289         return 0;
1290 }
1291
1292 int machine__process_event(struct machine *machine, union perf_event *event,
1293                            struct perf_sample *sample)
1294 {
1295         int ret;
1296
1297         switch (event->header.type) {
1298         case PERF_RECORD_COMM:
1299                 ret = machine__process_comm_event(machine, event, sample); break;
1300         case PERF_RECORD_MMAP:
1301                 ret = machine__process_mmap_event(machine, event, sample); break;
1302         case PERF_RECORD_MMAP2:
1303                 ret = machine__process_mmap2_event(machine, event, sample); break;
1304         case PERF_RECORD_FORK:
1305                 ret = machine__process_fork_event(machine, event, sample); break;
1306         case PERF_RECORD_EXIT:
1307                 ret = machine__process_exit_event(machine, event, sample); break;
1308         case PERF_RECORD_LOST:
1309                 ret = machine__process_lost_event(machine, event, sample); break;
1310         default:
1311                 ret = -1;
1312                 break;
1313         }
1314
1315         return ret;
1316 }
1317
1318 static bool symbol__match_regex(struct symbol *sym, regex_t *regex)
1319 {
1320         if (sym->name && !regexec(regex, sym->name, 0, NULL, 0))
1321                 return 1;
1322         return 0;
1323 }
1324
1325 static void ip__resolve_ams(struct thread *thread,
1326                             struct addr_map_symbol *ams,
1327                             u64 ip)
1328 {
1329         struct addr_location al;
1330
1331         memset(&al, 0, sizeof(al));
1332         /*
1333          * We cannot use the header.misc hint to determine whether a
1334          * branch stack address is user, kernel, guest, hypervisor.
1335          * Branches may straddle the kernel/user/hypervisor boundaries.
1336          * Thus, we have to try consecutively until we find a match
1337          * or else, the symbol is unknown
1338          */
1339         thread__find_cpumode_addr_location(thread, MAP__FUNCTION, ip, &al);
1340
1341         ams->addr = ip;
1342         ams->al_addr = al.addr;
1343         ams->sym = al.sym;
1344         ams->map = al.map;
1345 }
1346
1347 static void ip__resolve_data(struct thread *thread,
1348                              u8 m, struct addr_map_symbol *ams, u64 addr)
1349 {
1350         struct addr_location al;
1351
1352         memset(&al, 0, sizeof(al));
1353
1354         thread__find_addr_location(thread, m, MAP__VARIABLE, addr, &al);
1355         if (al.map == NULL) {
1356                 /*
1357                  * some shared data regions have execute bit set which puts
1358                  * their mapping in the MAP__FUNCTION type array.
1359                  * Check there as a fallback option before dropping the sample.
1360                  */
1361                 thread__find_addr_location(thread, m, MAP__FUNCTION, addr, &al);
1362         }
1363
1364         ams->addr = addr;
1365         ams->al_addr = al.addr;
1366         ams->sym = al.sym;
1367         ams->map = al.map;
1368 }
1369
1370 struct mem_info *sample__resolve_mem(struct perf_sample *sample,
1371                                      struct addr_location *al)
1372 {
1373         struct mem_info *mi = zalloc(sizeof(*mi));
1374
1375         if (!mi)
1376                 return NULL;
1377
1378         ip__resolve_ams(al->thread, &mi->iaddr, sample->ip);
1379         ip__resolve_data(al->thread, al->cpumode, &mi->daddr, sample->addr);
1380         mi->data_src.val = sample->data_src;
1381
1382         return mi;
1383 }
1384
1385 static int add_callchain_ip(struct thread *thread,
1386                             struct symbol **parent,
1387                             struct addr_location *root_al,
1388                             bool branch_history,
1389                             u64 ip)
1390 {
1391         struct addr_location al;
1392
1393         al.filtered = 0;
1394         al.sym = NULL;
1395         if (branch_history)
1396                 thread__find_cpumode_addr_location(thread, MAP__FUNCTION,
1397                                                    ip, &al);
1398         else {
1399                 u8 cpumode = PERF_RECORD_MISC_USER;
1400
1401                 if (ip >= PERF_CONTEXT_MAX) {
1402                         switch (ip) {
1403                         case PERF_CONTEXT_HV:
1404                                 cpumode = PERF_RECORD_MISC_HYPERVISOR;
1405                                 break;
1406                         case PERF_CONTEXT_KERNEL:
1407                                 cpumode = PERF_RECORD_MISC_KERNEL;
1408                                 break;
1409                         case PERF_CONTEXT_USER:
1410                                 cpumode = PERF_RECORD_MISC_USER;
1411                                 break;
1412                         default:
1413                                 pr_debug("invalid callchain context: "
1414                                          "%"PRId64"\n", (s64) ip);
1415                                 /*
1416                                  * It seems the callchain is corrupted.
1417                                  * Discard all.
1418                                  */
1419                                 callchain_cursor_reset(&callchain_cursor);
1420                                 return 1;
1421                         }
1422                         return 0;
1423                 }
1424                 thread__find_addr_location(thread, cpumode, MAP__FUNCTION,
1425                                    ip, &al);
1426         }
1427
1428         if (al.sym != NULL) {
1429                 if (sort__has_parent && !*parent &&
1430                     symbol__match_regex(al.sym, &parent_regex))
1431                         *parent = al.sym;
1432                 else if (have_ignore_callees && root_al &&
1433                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
1434                         /* Treat this symbol as the root,
1435                            forgetting its callees. */
1436                         *root_al = al;
1437                         callchain_cursor_reset(&callchain_cursor);
1438                 }
1439         }
1440
1441         return callchain_cursor_append(&callchain_cursor, al.addr, al.map, al.sym);
1442 }
1443
1444 struct branch_info *sample__resolve_bstack(struct perf_sample *sample,
1445                                            struct addr_location *al)
1446 {
1447         unsigned int i;
1448         const struct branch_stack *bs = sample->branch_stack;
1449         struct branch_info *bi = calloc(bs->nr, sizeof(struct branch_info));
1450
1451         if (!bi)
1452                 return NULL;
1453
1454         for (i = 0; i < bs->nr; i++) {
1455                 ip__resolve_ams(al->thread, &bi[i].to, bs->entries[i].to);
1456                 ip__resolve_ams(al->thread, &bi[i].from, bs->entries[i].from);
1457                 bi[i].flags = bs->entries[i].flags;
1458         }
1459         return bi;
1460 }
1461
1462 #define CHASHSZ 127
1463 #define CHASHBITS 7
1464 #define NO_ENTRY 0xff
1465
1466 #define PERF_MAX_BRANCH_DEPTH 127
1467
1468 /* Remove loops. */
1469 static int remove_loops(struct branch_entry *l, int nr)
1470 {
1471         int i, j, off;
1472         unsigned char chash[CHASHSZ];
1473
1474         memset(chash, NO_ENTRY, sizeof(chash));
1475
1476         BUG_ON(PERF_MAX_BRANCH_DEPTH > 255);
1477
1478         for (i = 0; i < nr; i++) {
1479                 int h = hash_64(l[i].from, CHASHBITS) % CHASHSZ;
1480
1481                 /* no collision handling for now */
1482                 if (chash[h] == NO_ENTRY) {
1483                         chash[h] = i;
1484                 } else if (l[chash[h]].from == l[i].from) {
1485                         bool is_loop = true;
1486                         /* check if it is a real loop */
1487                         off = 0;
1488                         for (j = chash[h]; j < i && i + off < nr; j++, off++)
1489                                 if (l[j].from != l[i + off].from) {
1490                                         is_loop = false;
1491                                         break;
1492                                 }
1493                         if (is_loop) {
1494                                 memmove(l + i, l + i + off,
1495                                         (nr - (i + off)) * sizeof(*l));
1496                                 nr -= off;
1497                         }
1498                 }
1499         }
1500         return nr;
1501 }
1502
1503 static int thread__resolve_callchain_sample(struct thread *thread,
1504                                              struct ip_callchain *chain,
1505                                              struct branch_stack *branch,
1506                                              struct symbol **parent,
1507                                              struct addr_location *root_al,
1508                                              int max_stack)
1509 {
1510         int chain_nr = min(max_stack, (int)chain->nr);
1511         int i, j, err;
1512         int skip_idx = -1;
1513         int first_call = 0;
1514
1515         /*
1516          * Based on DWARF debug information, some architectures skip
1517          * a callchain entry saved by the kernel.
1518          */
1519         if (chain->nr < PERF_MAX_STACK_DEPTH)
1520                 skip_idx = arch_skip_callchain_idx(thread, chain);
1521
1522         callchain_cursor_reset(&callchain_cursor);
1523
1524         /*
1525          * Add branches to call stack for easier browsing. This gives
1526          * more context for a sample than just the callers.
1527          *
1528          * This uses individual histograms of paths compared to the
1529          * aggregated histograms the normal LBR mode uses.
1530          *
1531          * Limitations for now:
1532          * - No extra filters
1533          * - No annotations (should annotate somehow)
1534          */
1535
1536         if (branch && callchain_param.branch_callstack) {
1537                 int nr = min(max_stack, (int)branch->nr);
1538                 struct branch_entry be[nr];
1539
1540                 if (branch->nr > PERF_MAX_BRANCH_DEPTH) {
1541                         pr_warning("corrupted branch chain. skipping...\n");
1542                         goto check_calls;
1543                 }
1544
1545                 for (i = 0; i < nr; i++) {
1546                         if (callchain_param.order == ORDER_CALLEE) {
1547                                 be[i] = branch->entries[i];
1548                                 /*
1549                                  * Check for overlap into the callchain.
1550                                  * The return address is one off compared to
1551                                  * the branch entry. To adjust for this
1552                                  * assume the calling instruction is not longer
1553                                  * than 8 bytes.
1554                                  */
1555                                 if (i == skip_idx ||
1556                                     chain->ips[first_call] >= PERF_CONTEXT_MAX)
1557                                         first_call++;
1558                                 else if (be[i].from < chain->ips[first_call] &&
1559                                     be[i].from >= chain->ips[first_call] - 8)
1560                                         first_call++;
1561                         } else
1562                                 be[i] = branch->entries[branch->nr - i - 1];
1563                 }
1564
1565                 nr = remove_loops(be, nr);
1566
1567                 for (i = 0; i < nr; i++) {
1568                         err = add_callchain_ip(thread, parent, root_al,
1569                                                true, be[i].to);
1570                         if (!err)
1571                                 err = add_callchain_ip(thread, parent, root_al,
1572                                                        true, be[i].from);
1573                         if (err == -EINVAL)
1574                                 break;
1575                         if (err)
1576                                 return err;
1577                 }
1578                 chain_nr -= nr;
1579         }
1580
1581 check_calls:
1582         if (chain->nr > PERF_MAX_STACK_DEPTH) {
1583                 pr_warning("corrupted callchain. skipping...\n");
1584                 return 0;
1585         }
1586
1587         for (i = first_call; i < chain_nr; i++) {
1588                 u64 ip;
1589
1590                 if (callchain_param.order == ORDER_CALLEE)
1591                         j = i;
1592                 else
1593                         j = chain->nr - i - 1;
1594
1595 #ifdef HAVE_SKIP_CALLCHAIN_IDX
1596                 if (j == skip_idx)
1597                         continue;
1598 #endif
1599                 ip = chain->ips[j];
1600
1601                 err = add_callchain_ip(thread, parent, root_al, false, ip);
1602
1603                 if (err)
1604                         return (err < 0) ? err : 0;
1605         }
1606
1607         return 0;
1608 }
1609
1610 static int unwind_entry(struct unwind_entry *entry, void *arg)
1611 {
1612         struct callchain_cursor *cursor = arg;
1613         return callchain_cursor_append(cursor, entry->ip,
1614                                        entry->map, entry->sym);
1615 }
1616
1617 int thread__resolve_callchain(struct thread *thread,
1618                               struct perf_evsel *evsel,
1619                               struct perf_sample *sample,
1620                               struct symbol **parent,
1621                               struct addr_location *root_al,
1622                               int max_stack)
1623 {
1624         int ret = thread__resolve_callchain_sample(thread, sample->callchain,
1625                                                    sample->branch_stack,
1626                                                    parent, root_al, max_stack);
1627         if (ret)
1628                 return ret;
1629
1630         /* Can we do dwarf post unwind? */
1631         if (!((evsel->attr.sample_type & PERF_SAMPLE_REGS_USER) &&
1632               (evsel->attr.sample_type & PERF_SAMPLE_STACK_USER)))
1633                 return 0;
1634
1635         /* Bail out if nothing was captured. */
1636         if ((!sample->user_regs.regs) ||
1637             (!sample->user_stack.size))
1638                 return 0;
1639
1640         return unwind__get_entries(unwind_entry, &callchain_cursor,
1641                                    thread, sample, max_stack);
1642
1643 }
1644
1645 int machine__for_each_thread(struct machine *machine,
1646                              int (*fn)(struct thread *thread, void *p),
1647                              void *priv)
1648 {
1649         struct rb_node *nd;
1650         struct thread *thread;
1651         int rc = 0;
1652
1653         for (nd = rb_first(&machine->threads); nd; nd = rb_next(nd)) {
1654                 thread = rb_entry(nd, struct thread, rb_node);
1655                 rc = fn(thread, priv);
1656                 if (rc != 0)
1657                         return rc;
1658         }
1659
1660         list_for_each_entry(thread, &machine->dead_threads, node) {
1661                 rc = fn(thread, priv);
1662                 if (rc != 0)
1663                         return rc;
1664         }
1665         return rc;
1666 }
1667
1668 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
1669                                   struct target *target, struct thread_map *threads,
1670                                   perf_event__handler_t process, bool data_mmap)
1671 {
1672         if (target__has_task(target))
1673                 return perf_event__synthesize_thread_map(tool, threads, process, machine, data_mmap);
1674         else if (target__has_cpu(target))
1675                 return perf_event__synthesize_threads(tool, process, machine, data_mmap);
1676         /* command specified */
1677         return 0;
1678 }
1679
1680 pid_t machine__get_current_tid(struct machine *machine, int cpu)
1681 {
1682         if (cpu < 0 || cpu >= MAX_NR_CPUS || !machine->current_tid)
1683                 return -1;
1684
1685         return machine->current_tid[cpu];
1686 }
1687
1688 int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
1689                              pid_t tid)
1690 {
1691         struct thread *thread;
1692
1693         if (cpu < 0)
1694                 return -EINVAL;
1695
1696         if (!machine->current_tid) {
1697                 int i;
1698
1699                 machine->current_tid = calloc(MAX_NR_CPUS, sizeof(pid_t));
1700                 if (!machine->current_tid)
1701                         return -ENOMEM;
1702                 for (i = 0; i < MAX_NR_CPUS; i++)
1703                         machine->current_tid[i] = -1;
1704         }
1705
1706         if (cpu >= MAX_NR_CPUS) {
1707                 pr_err("Requested CPU %d too large. ", cpu);
1708                 pr_err("Consider raising MAX_NR_CPUS\n");
1709                 return -EINVAL;
1710         }
1711
1712         machine->current_tid[cpu] = tid;
1713
1714         thread = machine__findnew_thread(machine, pid, tid);
1715         if (!thread)
1716                 return -ENOMEM;
1717
1718         thread->cpu = cpu;
1719
1720         return 0;
1721 }
1722
1723 int machine__get_kernel_start(struct machine *machine)
1724 {
1725         struct map *map = machine__kernel_map(machine, MAP__FUNCTION);
1726         int err = 0;
1727
1728         /*
1729          * The only addresses above 2^63 are kernel addresses of a 64-bit
1730          * kernel.  Note that addresses are unsigned so that on a 32-bit system
1731          * all addresses including kernel addresses are less than 2^32.  In
1732          * that case (32-bit system), if the kernel mapping is unknown, all
1733          * addresses will be assumed to be in user space - see
1734          * machine__kernel_ip().
1735          */
1736         machine->kernel_start = 1ULL << 63;
1737         if (map) {
1738                 err = map__load(map, machine->symbol_filter);
1739                 if (map->start)
1740                         machine->kernel_start = map->start;
1741         }
1742         return err;
1743 }