tools/perf/util/header.c

   1 #include "util.h"
   2 #include <sys/types.h>
   3 #include <byteswap.h>
   4 #include <unistd.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <linux/list.h>
   8 #include <linux/kernel.h>
   9 #include <linux/bitops.h>
  10 #include <sys/utsname.h>
  11
  12 #include "evlist.h"
  13 #include "evsel.h"
  14 #include "header.h"
  15 #include "../perf.h"
  16 #include "trace-event.h"
  17 #include "session.h"
  18 #include "symbol.h"
  19 #include "debug.h"
  20 #include "cpumap.h"
  21 #include "pmu.h"
  22 #include "vdso.h"
  23 #include "strbuf.h"
  24 #include "build-id.h"
  25
  26 static bool no_buildid_cache = false;
  27
  28 static u32 header_argc;
  29 static const char **header_argv;
  30
  31 /*
  32  * magic2 = "PERFILE2"
  33  * must be a numerical value to let the endianness
  34  * determine the memory layout. That way we are able
  35  * to detect endianness when reading the perf.data file
  36  * back.
  37  *
  38  * we check for legacy (PERFFILE) format.
  39  */
  40 static const char *__perf_magic1 = "PERFFILE";
  41 static const u64 __perf_magic2    = 0x32454c4946524550ULL;
  42 static const u64 __perf_magic2_sw = 0x50455246494c4532ULL;
  43
  44 #define PERF_MAGIC      __perf_magic2
  45
  46 struct perf_file_attr {
  47         struct perf_event_attr  attr;
  48         struct perf_file_section        ids;
  49 };
  50
  51 void perf_header__set_feat(struct perf_header *header, int feat)
  52 {
  53         set_bit(feat, header->adds_features);
  54 }
  55
  56 void perf_header__clear_feat(struct perf_header *header, int feat)
  57 {
  58         clear_bit(feat, header->adds_features);
  59 }
  60
  61 bool perf_header__has_feat(const struct perf_header *header, int feat)
  62 {
  63         return test_bit(feat, header->adds_features);
  64 }
  65
  66 static int do_write(int fd, const void *buf, size_t size)
  67 {
  68         while (size) {
  69                 int ret = write(fd, buf, size);
  70
  71                 if (ret < 0)
  72                         return -errno;
  73
  74                 size -= ret;
  75                 buf += ret;
  76         }
  77
  78         return 0;
  79 }
  80
  81 #define NAME_ALIGN 64
  82
  83 static int write_padded(int fd, const void *bf, size_t count,
  84                         size_t count_aligned)
  85 {
  86         static const char zero_buf[NAME_ALIGN];
  87         int err = do_write(fd, bf, count);
  88
  89         if (!err)
  90                 err = do_write(fd, zero_buf, count_aligned - count);
  91
  92         return err;
  93 }
  94
  95 static int do_write_string(int fd, const char *str)
  96 {
  97         u32 len, olen;
  98         int ret;
  99
 100         olen = strlen(str) + 1;
 101         len = PERF_ALIGN(olen, NAME_ALIGN);
 102
 103         /* write len, incl. \0 */
 104         ret = do_write(fd, &len, sizeof(len));
 105         if (ret < 0)
 106                 return ret;
 107
 108         return write_padded(fd, str, olen, len);
 109 }
 110
 111 static char *do_read_string(int fd, struct perf_header *ph)
 112 {
 113         ssize_t sz, ret;
 114         u32 len;
 115         char *buf;
 116
 117         sz = readn(fd, &len, sizeof(len));
 118         if (sz < (ssize_t)sizeof(len))
 119                 return NULL;
 120
 121         if (ph->needs_swap)
 122                 len = bswap_32(len);
 123
 124         buf = malloc(len);
 125         if (!buf)
 126                 return NULL;
 127
 128         ret = readn(fd, buf, len);
 129         if (ret == (ssize_t)len) {
 130                 /*
 131                  * strings are padded by zeroes
 132                  * thus the actual strlen of buf
 133                  * may be less than len
 134                  */
 135                 return buf;
 136         }
 137
 138         free(buf);
 139         return NULL;
 140 }
 141
 142 int
 143 perf_header__set_cmdline(int argc, const char **argv)
 144 {
 145         int i;
 146
 147         /*
 148          * If header_argv has already been set, do not override it.
 149          * This allows a command to set the cmdline, parse args and
 150          * then call another builtin function that implements a
 151          * command -- e.g, cmd_kvm calling cmd_record.
 152          */
 153         if (header_argv)
 154                 return 0;
 155
 156         header_argc = (u32)argc;
 157
 158         /* do not include NULL termination */
 159         header_argv = calloc(argc, sizeof(char *));
 160         if (!header_argv)
 161                 return -ENOMEM;
 162
 163         /*
 164          * must copy argv contents because it gets moved
 165          * around during option parsing
 166          */
 167         for (i = 0; i < argc ; i++)
 168                 header_argv[i] = argv[i];
 169
 170         return 0;
 171 }
 172
 173 #define dsos__for_each_with_build_id(pos, head) \
 174         list_for_each_entry(pos, head, node)    \
 175                 if (!pos->has_build_id)         \
 176                         continue;               \
 177                 else
 178
 179 static int write_buildid(char *name, size_t name_len, u8 *build_id,
 180                          pid_t pid, u16 misc, int fd)
 181 {
 182         int err;
 183         struct build_id_event b;
 184         size_t len;
 185
 186         len = name_len + 1;
 187         len = PERF_ALIGN(len, NAME_ALIGN);
 188
 189         memset(&b, 0, sizeof(b));
 190         memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
 191         b.pid = pid;
 192         b.header.misc = misc;
 193         b.header.size = sizeof(b) + len;
 194
 195         err = do_write(fd, &b, sizeof(b));
 196         if (err < 0)
 197                 return err;
 198
 199         return write_padded(fd, name, name_len + 1, len);
 200 }
 201
 202 static int __dsos__write_buildid_table(struct list_head *head, pid_t pid,
 203                                 u16 misc, int fd)
 204 {
 205         struct dso *pos;
 206
 207         dsos__for_each_with_build_id(pos, head) {
 208                 int err;
 209                 char  *name;
 210                 size_t name_len;
 211
 212                 if (!pos->hit)
 213                         continue;
 214
 215                 if (is_vdso_map(pos->short_name)) {
 216                         name = (char *) VDSO__MAP_NAME;
 217                         name_len = sizeof(VDSO__MAP_NAME) + 1;
 218                 } else {
 219                         name = pos->long_name;
 220                         name_len = pos->long_name_len + 1;
 221                 }
 222
 223                 err = write_buildid(name, name_len, pos->build_id,
 224                                     pid, misc, fd);
 225                 if (err)
 226                         return err;
 227         }
 228
 229         return 0;
 230 }
 231
 232 static int machine__write_buildid_table(struct machine *machine, int fd)
 233 {
 234         int err;
 235         u16 kmisc = PERF_RECORD_MISC_KERNEL,
 236             umisc = PERF_RECORD_MISC_USER;
 237
 238         if (!machine__is_host(machine)) {
 239                 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
 240                 umisc = PERF_RECORD_MISC_GUEST_USER;
 241         }
 242
 243         err = __dsos__write_buildid_table(&machine->kernel_dsos, machine->pid,
 244                                           kmisc, fd);
 245         if (err == 0)
 246                 err = __dsos__write_buildid_table(&machine->user_dsos,
 247                                                   machine->pid, umisc, fd);
 248         return err;
 249 }
 250
 251 static int dsos__write_buildid_table(struct perf_header *header, int fd)
 252 {
 253         struct perf_session *session = container_of(header,
 254                         struct perf_session, header);
 255         struct rb_node *nd;
 256         int err = machine__write_buildid_table(&session->machines.host, fd);
 257
 258         if (err)
 259                 return err;
 260
 261         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
 262                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 263                 err = machine__write_buildid_table(pos, fd);
 264                 if (err)
 265                         break;
 266         }
 267         return err;
 268 }
 269
 270 int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
 271                           const char *name, bool is_kallsyms, bool is_vdso)
 272 {
 273         const size_t size = PATH_MAX;
 274         char *realname, *filename = zalloc(size),
 275              *linkname = zalloc(size), *targetname;
 276         int len, err = -1;
 277         bool slash = is_kallsyms || is_vdso;
 278
 279         if (is_kallsyms) {
 280                 if (symbol_conf.kptr_restrict) {
 281                         pr_debug("Not caching a kptr_restrict'ed /proc/kallsyms\n");
 282                         err = 0;
 283                         goto out_free;
 284                 }
 285                 realname = (char *) name;
 286         } else
 287                 realname = realpath(name, NULL);
 288
 289         if (realname == NULL || filename == NULL || linkname == NULL)
 290                 goto out_free;
 291
 292         len = scnprintf(filename, size, "%s%s%s",
 293                        debugdir, slash ? "/" : "",
 294                        is_vdso ? VDSO__MAP_NAME : realname);
 295         if (mkdir_p(filename, 0755))
 296                 goto out_free;
 297
 298         snprintf(filename + len, size - len, "/%s", sbuild_id);
 299
 300         if (access(filename, F_OK)) {
 301                 if (is_kallsyms) {
 302                          if (copyfile("/proc/kallsyms", filename))
 303                                 goto out_free;
 304                 } else if (link(realname, filename) && copyfile(name, filename))
 305                         goto out_free;
 306         }
 307
 308         len = scnprintf(linkname, size, "%s/.build-id/%.2s",
 309                        debugdir, sbuild_id);
 310
 311         if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
 312                 goto out_free;
 313
 314         snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
 315         targetname = filename + strlen(debugdir) - 5;
 316         memcpy(targetname, "../..", 5);
 317
 318         if (symlink(targetname, linkname) == 0)
 319                 err = 0;
 320 out_free:
 321         if (!is_kallsyms)
 322                 free(realname);
 323         free(filename);
 324         free(linkname);
 325         return err;
 326 }
 327
 328 static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
 329                                  const char *name, const char *debugdir,
 330                                  bool is_kallsyms, bool is_vdso)
 331 {
 332         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
 333
 334         build_id__sprintf(build_id, build_id_size, sbuild_id);
 335
 336         return build_id_cache__add_s(sbuild_id, debugdir, name,
 337                                      is_kallsyms, is_vdso);
 338 }
 339
 340 int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir)
 341 {
 342         const size_t size = PATH_MAX;
 343         char *filename = zalloc(size),
 344              *linkname = zalloc(size);
 345         int err = -1;
 346
 347         if (filename == NULL || linkname == NULL)
 348                 goto out_free;
 349
 350         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
 351                  debugdir, sbuild_id, sbuild_id + 2);
 352
 353         if (access(linkname, F_OK))
 354                 goto out_free;
 355
 356         if (readlink(linkname, filename, size - 1) < 0)
 357                 goto out_free;
 358
 359         if (unlink(linkname))
 360                 goto out_free;
 361
 362         /*
 363          * Since the link is relative, we must make it absolute:
 364          */
 365         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
 366                  debugdir, sbuild_id, filename);
 367
 368         if (unlink(linkname))
 369                 goto out_free;
 370
 371         err = 0;
 372 out_free:
 373         free(filename);
 374         free(linkname);
 375         return err;
 376 }
 377
 378 static int dso__cache_build_id(struct dso *dso, const char *debugdir)
 379 {
 380         bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
 381         bool is_vdso = is_vdso_map(dso->short_name);
 382
 383         return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id),
 384                                      dso->long_name, debugdir,
 385                                      is_kallsyms, is_vdso);
 386 }
 387
 388 static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
 389 {
 390         struct dso *pos;
 391         int err = 0;
 392
 393         dsos__for_each_with_build_id(pos, head)
 394                 if (dso__cache_build_id(pos, debugdir))
 395                         err = -1;
 396
 397         return err;
 398 }
 399
 400 static int machine__cache_build_ids(struct machine *machine, const char *debugdir)
 401 {
 402         int ret = __dsos__cache_build_ids(&machine->kernel_dsos, debugdir);
 403         ret |= __dsos__cache_build_ids(&machine->user_dsos, debugdir);
 404         return ret;
 405 }
 406
 407 static int perf_session__cache_build_ids(struct perf_session *session)
 408 {
 409         struct rb_node *nd;
 410         int ret;
 411         char debugdir[PATH_MAX];
 412
 413         snprintf(debugdir, sizeof(debugdir), "%s", buildid_dir);
 414
 415         if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
 416                 return -1;
 417
 418         ret = machine__cache_build_ids(&session->machines.host, debugdir);
 419
 420         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
 421                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 422                 ret |= machine__cache_build_ids(pos, debugdir);
 423         }
 424         return ret ? -1 : 0;
 425 }
 426
 427 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
 428 {
 429         bool ret = __dsos__read_build_ids(&machine->kernel_dsos, with_hits);
 430         ret |= __dsos__read_build_ids(&machine->user_dsos, with_hits);
 431         return ret;
 432 }
 433
 434 static bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
 435 {
 436         struct rb_node *nd;
 437         bool ret = machine__read_build_ids(&session->machines.host, with_hits);
 438
 439         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
 440                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
 441                 ret |= machine__read_build_ids(pos, with_hits);
 442         }
 443
 444         return ret;
 445 }
 446
 447 static int write_tracing_data(int fd, struct perf_header *h __maybe_unused,
 448                             struct perf_evlist *evlist)
 449 {
 450         return read_tracing_data(fd, &evlist->entries);
 451 }
 452
 453
 454 static int write_build_id(int fd, struct perf_header *h,
 455                           struct perf_evlist *evlist __maybe_unused)
 456 {
 457         struct perf_session *session;
 458         int err;
 459
 460         session = container_of(h, struct perf_session, header);
 461
 462         if (!perf_session__read_build_ids(session, true))
 463                 return -1;
 464
 465         err = dsos__write_buildid_table(h, fd);
 466         if (err < 0) {
 467                 pr_debug("failed to write buildid table\n");
 468                 return err;
 469         }
 470         if (!no_buildid_cache)
 471                 perf_session__cache_build_ids(session);
 472
 473         return 0;
 474 }
 475
 476 static int write_hostname(int fd, struct perf_header *h __maybe_unused,
 477                           struct perf_evlist *evlist __maybe_unused)
 478 {
 479         struct utsname uts;
 480         int ret;
 481
 482         ret = uname(&uts);
 483         if (ret < 0)
 484                 return -1;
 485
 486         return do_write_string(fd, uts.nodename);
 487 }
 488
 489 static int write_osrelease(int fd, struct perf_header *h __maybe_unused,
 490                            struct perf_evlist *evlist __maybe_unused)
 491 {
 492         struct utsname uts;
 493         int ret;
 494
 495         ret = uname(&uts);
 496         if (ret < 0)
 497                 return -1;
 498
 499         return do_write_string(fd, uts.release);
 500 }
 501
 502 static int write_arch(int fd, struct perf_header *h __maybe_unused,
 503                       struct perf_evlist *evlist __maybe_unused)
 504 {
 505         struct utsname uts;
 506         int ret;
 507
 508         ret = uname(&uts);
 509         if (ret < 0)
 510                 return -1;
 511
 512         return do_write_string(fd, uts.machine);
 513 }
 514
 515 static int write_version(int fd, struct perf_header *h __maybe_unused,
 516                          struct perf_evlist *evlist __maybe_unused)
 517 {
 518         return do_write_string(fd, perf_version_string);
 519 }
 520
 521 static int write_cpudesc(int fd, struct perf_header *h __maybe_unused,
 522                        struct perf_evlist *evlist __maybe_unused)
 523 {
 524 #ifndef CPUINFO_PROC
 525 #define CPUINFO_PROC NULL
 526 #endif
 527         FILE *file;
 528         char *buf = NULL;
 529         char *s, *p;
 530         const char *search = CPUINFO_PROC;
 531         size_t len = 0;
 532         int ret = -1;
 533
 534         if (!search)
 535                 return -1;
 536
 537         file = fopen("/proc/cpuinfo", "r");
 538         if (!file)
 539                 return -1;
 540
 541         while (getline(&buf, &len, file) > 0) {
 542                 ret = strncmp(buf, search, strlen(search));
 543                 if (!ret)
 544                         break;
 545         }
 546
 547         if (ret)
 548                 goto done;
 549
 550         s = buf;
 551
 552         p = strchr(buf, ':');
 553         if (p && *(p+1) == ' ' && *(p+2))
 554                 s = p + 2;
 555         p = strchr(s, '\n');
 556         if (p)
 557                 *p = '\0';
 558
 559         /* squash extra space characters (branding string) */
 560         p = s;
 561         while (*p) {
 562                 if (isspace(*p)) {
 563                         char *r = p + 1;
 564                         char *q = r;
 565                         *p = ' ';
 566                         while (*q && isspace(*q))
 567                                 q++;
 568                         if (q != (p+1))
 569                                 while ((*r++ = *q++));
 570                 }
 571                 p++;
 572         }
 573         ret = do_write_string(fd, s);
 574 done:
 575         free(buf);
 576         fclose(file);
 577         return ret;
 578 }
 579
 580 static int write_nrcpus(int fd, struct perf_header *h __maybe_unused,
 581                         struct perf_evlist *evlist __maybe_unused)
 582 {
 583         long nr;
 584         u32 nrc, nra;
 585         int ret;
 586
 587         nr = sysconf(_SC_NPROCESSORS_CONF);
 588         if (nr < 0)
 589                 return -1;
 590
 591         nrc = (u32)(nr & UINT_MAX);
 592
 593         nr = sysconf(_SC_NPROCESSORS_ONLN);
 594         if (nr < 0)
 595                 return -1;
 596
 597         nra = (u32)(nr & UINT_MAX);
 598
 599         ret = do_write(fd, &nrc, sizeof(nrc));
 600         if (ret < 0)
 601                 return ret;
 602
 603         return do_write(fd, &nra, sizeof(nra));
 604 }
 605
 606 static int write_event_desc(int fd, struct perf_header *h __maybe_unused,
 607                             struct perf_evlist *evlist)
 608 {
 609         struct perf_evsel *evsel;
 610         u32 nre, nri, sz;
 611         int ret;
 612
 613         nre = evlist->nr_entries;
 614
 615         /*
 616          * write number of events
 617          */
 618         ret = do_write(fd, &nre, sizeof(nre));
 619         if (ret < 0)
 620                 return ret;
 621
 622         /*
 623          * size of perf_event_attr struct
 624          */
 625         sz = (u32)sizeof(evsel->attr);
 626         ret = do_write(fd, &sz, sizeof(sz));
 627         if (ret < 0)
 628                 return ret;
 629
 630         list_for_each_entry(evsel, &evlist->entries, node) {
 631
 632                 ret = do_write(fd, &evsel->attr, sz);
 633                 if (ret < 0)
 634                         return ret;
 635                 /*
 636                  * write number of unique id per event
 637                  * there is one id per instance of an event
 638                  *
 639                  * copy into an nri to be independent of the
 640                  * type of ids,
 641                  */
 642                 nri = evsel->ids;
 643                 ret = do_write(fd, &nri, sizeof(nri));
 644                 if (ret < 0)
 645                         return ret;
 646
 647                 /*
 648                  * write event string as passed on cmdline
 649                  */
 650                 ret = do_write_string(fd, perf_evsel__name(evsel));
 651                 if (ret < 0)
 652                         return ret;
 653                 /*
 654                  * write unique ids for this event
 655                  */
 656                 ret = do_write(fd, evsel->id, evsel->ids * sizeof(u64));
 657                 if (ret < 0)
 658                         return ret;
 659         }
 660         return 0;
 661 }
 662
 663 static int write_cmdline(int fd, struct perf_header *h __maybe_unused,
 664                          struct perf_evlist *evlist __maybe_unused)
 665 {
 666         char buf[MAXPATHLEN];
 667         char proc[32];
 668         u32 i, n;
 669         int ret;
 670
 671         /*
 672          * actual atual path to perf binary
 673          */
 674         sprintf(proc, "/proc/%d/exe", getpid());
 675         ret = readlink(proc, buf, sizeof(buf));
 676         if (ret <= 0)
 677                 return -1;
 678
 679         /* readlink() does not add null termination */
 680         buf[ret] = '\0';
 681
 682         /* account for binary path */
 683         n = header_argc + 1;
 684
 685         ret = do_write(fd, &n, sizeof(n));
 686         if (ret < 0)
 687                 return ret;
 688
 689         ret = do_write_string(fd, buf);
 690         if (ret < 0)
 691                 return ret;
 692
 693         for (i = 0 ; i < header_argc; i++) {
 694                 ret = do_write_string(fd, header_argv[i]);
 695                 if (ret < 0)
 696                         return ret;
 697         }
 698         return 0;
 699 }
 700
 701 #define CORE_SIB_FMT \
 702         "/sys/devices/system/cpu/cpu%d/topology/core_siblings_list"
 703 #define THRD_SIB_FMT \
 704         "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list"
 705
 706 struct cpu_topo {
 707         u32 core_sib;
 708         u32 thread_sib;
 709         char **core_siblings;
 710         char **thread_siblings;
 711 };
 712
 713 static int build_cpu_topo(struct cpu_topo *tp, int cpu)
 714 {
 715         FILE *fp;
 716         char filename[MAXPATHLEN];
 717         char *buf = NULL, *p;
 718         size_t len = 0;
 719         ssize_t sret;
 720         u32 i = 0;
 721         int ret = -1;
 722
 723         sprintf(filename, CORE_SIB_FMT, cpu);
 724         fp = fopen(filename, "r");
 725         if (!fp)
 726                 goto try_threads;
 727
 728         sret = getline(&buf, &len, fp);
 729         fclose(fp);
 730         if (sret <= 0)
 731                 goto try_threads;
 732
 733         p = strchr(buf, '\n');
 734         if (p)
 735                 *p = '\0';
 736
 737         for (i = 0; i < tp->core_sib; i++) {
 738                 if (!strcmp(buf, tp->core_siblings[i]))
 739                         break;
 740         }
 741         if (i == tp->core_sib) {
 742                 tp->core_siblings[i] = buf;
 743                 tp->core_sib++;
 744                 buf = NULL;
 745                 len = 0;
 746         }
 747         ret = 0;
 748
 749 try_threads:
 750         sprintf(filename, THRD_SIB_FMT, cpu);
 751         fp = fopen(filename, "r");
 752         if (!fp)
 753                 goto done;
 754
 755         if (getline(&buf, &len, fp) <= 0)
 756                 goto done;
 757
 758         p = strchr(buf, '\n');
 759         if (p)
 760                 *p = '\0';
 761
 762         for (i = 0; i < tp->thread_sib; i++) {
 763                 if (!strcmp(buf, tp->thread_siblings[i]))
 764                         break;
 765         }
 766         if (i == tp->thread_sib) {
 767                 tp->thread_siblings[i] = buf;
 768                 tp->thread_sib++;
 769                 buf = NULL;
 770         }
 771         ret = 0;
 772 done:
 773         if(fp)
 774                 fclose(fp);
 775         free(buf);
 776         return ret;
 777 }
 778
 779 static void free_cpu_topo(struct cpu_topo *tp)
 780 {
 781         u32 i;
 782
 783         if (!tp)
 784                 return;
 785
 786         for (i = 0 ; i < tp->core_sib; i++)
 787                 free(tp->core_siblings[i]);
 788
 789         for (i = 0 ; i < tp->thread_sib; i++)
 790                 free(tp->thread_siblings[i]);
 791
 792         free(tp);
 793 }
 794
 795 static struct cpu_topo *build_cpu_topology(void)
 796 {
 797         struct cpu_topo *tp;
 798         void *addr;
 799         u32 nr, i;
 800         size_t sz;
 801         long ncpus;
 802         int ret = -1;
 803
 804         ncpus = sysconf(_SC_NPROCESSORS_CONF);
 805         if (ncpus < 0)
 806                 return NULL;
 807
 808         nr = (u32)(ncpus & UINT_MAX);
 809
 810         sz = nr * sizeof(char *);
 811
 812         addr = calloc(1, sizeof(*tp) + 2 * sz);
 813         if (!addr)
 814                 return NULL;
 815
 816         tp = addr;
 817
 818         addr += sizeof(*tp);
 819         tp->core_siblings = addr;
 820         addr += sz;
 821         tp->thread_siblings = addr;
 822
 823         for (i = 0; i < nr; i++) {
 824                 ret = build_cpu_topo(tp, i);
 825                 if (ret < 0)
 826                         break;
 827         }
 828         if (ret) {
 829                 free_cpu_topo(tp);
 830                 tp = NULL;
 831         }
 832         return tp;
 833 }
 834
 835 static int write_cpu_topology(int fd, struct perf_header *h __maybe_unused,
 836                           struct perf_evlist *evlist __maybe_unused)
 837 {
 838         struct cpu_topo *tp;
 839         u32 i;
 840         int ret;
 841
 842         tp = build_cpu_topology();
 843         if (!tp)
 844                 return -1;
 845
 846         ret = do_write(fd, &tp->core_sib, sizeof(tp->core_sib));
 847         if (ret < 0)
 848                 goto done;
 849
 850         for (i = 0; i < tp->core_sib; i++) {
 851                 ret = do_write_string(fd, tp->core_siblings[i]);
 852                 if (ret < 0)
 853                         goto done;
 854         }
 855         ret = do_write(fd, &tp->thread_sib, sizeof(tp->thread_sib));
 856         if (ret < 0)
 857                 goto done;
 858
 859         for (i = 0; i < tp->thread_sib; i++) {
 860                 ret = do_write_string(fd, tp->thread_siblings[i]);
 861                 if (ret < 0)
 862                         break;
 863         }
 864 done:
 865         free_cpu_topo(tp);
 866         return ret;
 867 }
 868
 869
 870
 871 static int write_total_mem(int fd, struct perf_header *h __maybe_unused,
 872                           struct perf_evlist *evlist __maybe_unused)
 873 {
 874         char *buf = NULL;
 875         FILE *fp;
 876         size_t len = 0;
 877         int ret = -1, n;
 878         uint64_t mem;
 879
 880         fp = fopen("/proc/meminfo", "r");
 881         if (!fp)
 882                 return -1;
 883
 884         while (getline(&buf, &len, fp) > 0) {
 885                 ret = strncmp(buf, "MemTotal:", 9);
 886                 if (!ret)
 887                         break;
 888         }
 889         if (!ret) {
 890                 n = sscanf(buf, "%*s %"PRIu64, &mem);
 891                 if (n == 1)
 892                         ret = do_write(fd, &mem, sizeof(mem));
 893         }
 894         free(buf);
 895         fclose(fp);
 896         return ret;
 897 }
 898
 899 static int write_topo_node(int fd, int node)
 900 {
 901         char str[MAXPATHLEN];
 902         char field[32];
 903         char *buf = NULL, *p;
 904         size_t len = 0;
 905         FILE *fp;
 906         u64 mem_total, mem_free, mem;
 907         int ret = -1;
 908
 909         sprintf(str, "/sys/devices/system/node/node%d/meminfo", node);
 910         fp = fopen(str, "r");
 911         if (!fp)
 912                 return -1;
 913
 914         while (getline(&buf, &len, fp) > 0) {
 915                 /* skip over invalid lines */
 916                 if (!strchr(buf, ':'))
 917                         continue;
 918                 if (sscanf(buf, "%*s %*d %s %"PRIu64, field, &mem) != 2)
 919                         goto done;
 920                 if (!strcmp(field, "MemTotal:"))
 921                         mem_total = mem;
 922                 if (!strcmp(field, "MemFree:"))
 923                         mem_free = mem;
 924         }
 925
 926         fclose(fp);
 927         fp = NULL;
 928
 929         ret = do_write(fd, &mem_total, sizeof(u64));
 930         if (ret)
 931                 goto done;
 932
 933         ret = do_write(fd, &mem_free, sizeof(u64));
 934         if (ret)
 935                 goto done;
 936
 937         ret = -1;
 938         sprintf(str, "/sys/devices/system/node/node%d/cpulist", node);
 939
 940         fp = fopen(str, "r");
 941         if (!fp)
 942                 goto done;
 943
 944         if (getline(&buf, &len, fp) <= 0)
 945                 goto done;
 946
 947         p = strchr(buf, '\n');
 948         if (p)
 949                 *p = '\0';
 950
 951         ret = do_write_string(fd, buf);
 952 done:
 953         free(buf);
 954         if (fp)
 955                 fclose(fp);
 956         return ret;
 957 }
 958
 959 static int write_numa_topology(int fd, struct perf_header *h __maybe_unused,
 960                           struct perf_evlist *evlist __maybe_unused)
 961 {
 962         char *buf = NULL;
 963         size_t len = 0;
 964         FILE *fp;
 965         struct cpu_map *node_map = NULL;
 966         char *c;
 967         u32 nr, i, j;
 968         int ret = -1;
 969
 970         fp = fopen("/sys/devices/system/node/online", "r");
 971         if (!fp)
 972                 return -1;
 973
 974         if (getline(&buf, &len, fp) <= 0)
 975                 goto done;
 976
 977         c = strchr(buf, '\n');
 978         if (c)
 979                 *c = '\0';
 980
 981         node_map = cpu_map__new(buf);
 982         if (!node_map)
 983                 goto done;
 984
 985         nr = (u32)node_map->nr;
 986
 987         ret = do_write(fd, &nr, sizeof(nr));
 988         if (ret < 0)
 989                 goto done;
 990
 991         for (i = 0; i < nr; i++) {
 992                 j = (u32)node_map->map[i];
 993                 ret = do_write(fd, &j, sizeof(j));
 994                 if (ret < 0)
 995                         break;
 996
 997                 ret = write_topo_node(fd, i);
 998                 if (ret < 0)
 999                         break;
1000         }
1001 done:
1002         free(buf);
1003         fclose(fp);
1004         free(node_map);
1005         return ret;
1006 }
1007
1008 /*
1009  * File format:
1010  *
1011  * struct pmu_mappings {
1012  *      u32     pmu_num;
1013  *      struct pmu_map {
1014  *              u32     type;
1015  *              char    name[];
1016  *      }[pmu_num];
1017  * };
1018  */
1019
1020 static int write_pmu_mappings(int fd, struct perf_header *h __maybe_unused,
1021                               struct perf_evlist *evlist __maybe_unused)
1022 {
1023         struct perf_pmu *pmu = NULL;
1024         off_t offset = lseek(fd, 0, SEEK_CUR);
1025         __u32 pmu_num = 0;
1026         int ret;
1027
1028         /* write real pmu_num later */
1029         ret = do_write(fd, &pmu_num, sizeof(pmu_num));
1030         if (ret < 0)
1031                 return ret;
1032
1033         while ((pmu = perf_pmu__scan(pmu))) {
1034                 if (!pmu->name)
1035                         continue;
1036                 pmu_num++;
1037
1038                 ret = do_write(fd, &pmu->type, sizeof(pmu->type));
1039                 if (ret < 0)
1040                         return ret;
1041
1042                 ret = do_write_string(fd, pmu->name);
1043                 if (ret < 0)
1044                         return ret;
1045         }
1046
1047         if (pwrite(fd, &pmu_num, sizeof(pmu_num), offset) != sizeof(pmu_num)) {
1048                 /* discard all */
1049                 lseek(fd, offset, SEEK_SET);
1050                 return -1;
1051         }
1052
1053         return 0;
1054 }
1055
1056 /*
1057  * File format:
1058  *
1059  * struct group_descs {
1060  *      u32     nr_groups;
1061  *      struct group_desc {
1062  *              char    name[];
1063  *              u32     leader_idx;
1064  *              u32     nr_members;
1065  *      }[nr_groups];
1066  * };
1067  */
1068 static int write_group_desc(int fd, struct perf_header *h __maybe_unused,
1069                             struct perf_evlist *evlist)
1070 {
1071         u32 nr_groups = evlist->nr_groups;
1072         struct perf_evsel *evsel;
1073         int ret;
1074
1075         ret = do_write(fd, &nr_groups, sizeof(nr_groups));
1076         if (ret < 0)
1077                 return ret;
1078
1079         list_for_each_entry(evsel, &evlist->entries, node) {
1080                 if (perf_evsel__is_group_leader(evsel) &&
1081                     evsel->nr_members > 1) {
1082                         const char *name = evsel->group_name ?: "{anon_group}";
1083                         u32 leader_idx = evsel->idx;
1084                         u32 nr_members = evsel->nr_members;
1085
1086                         ret = do_write_string(fd, name);
1087                         if (ret < 0)
1088                                 return ret;
1089
1090                         ret = do_write(fd, &leader_idx, sizeof(leader_idx));
1091                         if (ret < 0)
1092                                 return ret;
1093
1094                         ret = do_write(fd, &nr_members, sizeof(nr_members));
1095                         if (ret < 0)
1096                                 return ret;
1097                 }
1098         }
1099         return 0;
1100 }
1101
1102 /*
1103  * default get_cpuid(): nothing gets recorded
1104  * actual implementation must be in arch/$(ARCH)/util/header.c
1105  */
1106 int __attribute__ ((weak)) get_cpuid(char *buffer __maybe_unused,
1107                                      size_t sz __maybe_unused)
1108 {
1109         return -1;
1110 }
1111
1112 static int write_cpuid(int fd, struct perf_header *h __maybe_unused,
1113                        struct perf_evlist *evlist __maybe_unused)
1114 {
1115         char buffer[64];
1116         int ret;
1117
1118         ret = get_cpuid(buffer, sizeof(buffer));
1119         if (!ret)
1120                 goto write_it;
1121
1122         return -1;
1123 write_it:
1124         return do_write_string(fd, buffer);
1125 }
1126
1127 static int write_branch_stack(int fd __maybe_unused,
1128                               struct perf_header *h __maybe_unused,
1129                        struct perf_evlist *evlist __maybe_unused)
1130 {
1131         return 0;
1132 }
1133
1134 static void print_hostname(struct perf_header *ph, int fd __maybe_unused,
1135                            FILE *fp)
1136 {
1137         fprintf(fp, "# hostname : %s\n", ph->env.hostname);
1138 }
1139
1140 static void print_osrelease(struct perf_header *ph, int fd __maybe_unused,
1141                             FILE *fp)
1142 {
1143         fprintf(fp, "# os release : %s\n", ph->env.os_release);
1144 }
1145
1146 static void print_arch(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
1147 {
1148         fprintf(fp, "# arch : %s\n", ph->env.arch);
1149 }
1150
1151 static void print_cpudesc(struct perf_header *ph, int fd __maybe_unused,
1152                           FILE *fp)
1153 {
1154         fprintf(fp, "# cpudesc : %s\n", ph->env.cpu_desc);
1155 }
1156
1157 static void print_nrcpus(struct perf_header *ph, int fd __maybe_unused,
1158                          FILE *fp)
1159 {
1160         fprintf(fp, "# nrcpus online : %u\n", ph->env.nr_cpus_online);
1161         fprintf(fp, "# nrcpus avail : %u\n", ph->env.nr_cpus_avail);
1162 }
1163
1164 static void print_version(struct perf_header *ph, int fd __maybe_unused,
1165                           FILE *fp)
1166 {
1167         fprintf(fp, "# perf version : %s\n", ph->env.version);
1168 }
1169
1170 static void print_cmdline(struct perf_header *ph, int fd __maybe_unused,
1171                           FILE *fp)
1172 {
1173         int nr, i;
1174         char *str;
1175
1176         nr = ph->env.nr_cmdline;
1177         str = ph->env.cmdline;
1178
1179         fprintf(fp, "# cmdline : ");
1180
1181         for (i = 0; i < nr; i++) {
1182                 fprintf(fp, "%s ", str);
1183                 str += strlen(str) + 1;
1184         }
1185         fputc('\n', fp);
1186 }
1187
1188 static void print_cpu_topology(struct perf_header *ph, int fd __maybe_unused,
1189                                FILE *fp)
1190 {
1191         int nr, i;
1192         char *str;
1193
1194         nr = ph->env.nr_sibling_cores;
1195         str = ph->env.sibling_cores;
1196
1197         for (i = 0; i < nr; i++) {
1198                 fprintf(fp, "# sibling cores   : %s\n", str);
1199                 str += strlen(str) + 1;
1200         }
1201
1202         nr = ph->env.nr_sibling_threads;
1203         str = ph->env.sibling_threads;
1204
1205         for (i = 0; i < nr; i++) {
1206                 fprintf(fp, "# sibling threads : %s\n", str);
1207                 str += strlen(str) + 1;
1208         }
1209 }
1210
1211 static void free_event_desc(struct perf_evsel *events)
1212 {
1213         struct perf_evsel *evsel;
1214
1215         if (!events)
1216                 return;
1217
1218         for (evsel = events; evsel->attr.size; evsel++) {
1219                 if (evsel->name)
1220                         free(evsel->name);
1221                 if (evsel->id)
1222                         free(evsel->id);
1223         }
1224
1225         free(events);
1226 }
1227
1228 static struct perf_evsel *
1229 read_event_desc(struct perf_header *ph, int fd)
1230 {
1231         struct perf_evsel *evsel, *events = NULL;
1232         u64 *id;
1233         void *buf = NULL;
1234         u32 nre, sz, nr, i, j;
1235         ssize_t ret;
1236         size_t msz;
1237
1238         /* number of events */
1239         ret = readn(fd, &nre, sizeof(nre));
1240         if (ret != (ssize_t)sizeof(nre))
1241                 goto error;
1242
1243         if (ph->needs_swap)
1244                 nre = bswap_32(nre);
1245
1246         ret = readn(fd, &sz, sizeof(sz));
1247         if (ret != (ssize_t)sizeof(sz))
1248                 goto error;
1249
1250         if (ph->needs_swap)
1251                 sz = bswap_32(sz);
1252
1253         /* buffer to hold on file attr struct */
1254         buf = malloc(sz);
1255         if (!buf)
1256                 goto error;
1257
1258         /* the last event terminates with evsel->attr.size == 0: */
1259         events = calloc(nre + 1, sizeof(*events));
1260         if (!events)
1261                 goto error;
1262
1263         msz = sizeof(evsel->attr);
1264         if (sz < msz)
1265                 msz = sz;
1266
1267         for (i = 0, evsel = events; i < nre; evsel++, i++) {
1268                 evsel->idx = i;
1269
1270                 /*
1271                  * must read entire on-file attr struct to
1272                  * sync up with layout.
1273                  */
1274                 ret = readn(fd, buf, sz);
1275                 if (ret != (ssize_t)sz)
1276                         goto error;
1277
1278                 if (ph->needs_swap)
1279                         perf_event__attr_swap(buf);
1280
1281                 memcpy(&evsel->attr, buf, msz);
1282
1283                 ret = readn(fd, &nr, sizeof(nr));
1284                 if (ret != (ssize_t)sizeof(nr))
1285                         goto error;
1286
1287                 if (ph->needs_swap) {
1288                         nr = bswap_32(nr);
1289                         evsel->needs_swap = true;
1290                 }
1291
1292                 evsel->name = do_read_string(fd, ph);
1293
1294                 if (!nr)
1295                         continue;
1296
1297                 id = calloc(nr, sizeof(*id));
1298                 if (!id)
1299                         goto error;
1300                 evsel->ids = nr;
1301                 evsel->id = id;
1302
1303                 for (j = 0 ; j < nr; j++) {
1304                         ret = readn(fd, id, sizeof(*id));
1305                         if (ret != (ssize_t)sizeof(*id))
1306                                 goto error;
1307                         if (ph->needs_swap)
1308                                 *id = bswap_64(*id);
1309                         id++;
1310                 }
1311         }
1312 out:
1313         if (buf)
1314                 free(buf);
1315         return events;
1316 error:
1317         if (events)
1318                 free_event_desc(events);
1319         events = NULL;
1320         goto out;
1321 }
1322
1323 static void print_event_desc(struct perf_header *ph, int fd, FILE *fp)
1324 {
1325         struct perf_evsel *evsel, *events = read_event_desc(ph, fd);
1326         u32 j;
1327         u64 *id;
1328
1329         if (!events) {
1330                 fprintf(fp, "# event desc: not available or unable to read\n");
1331                 return;
1332         }
1333
1334         for (evsel = events; evsel->attr.size; evsel++) {
1335                 fprintf(fp, "# event : name = %s, ", evsel->name);
1336
1337                 fprintf(fp, "type = %d, config = 0x%"PRIx64
1338                             ", config1 = 0x%"PRIx64", config2 = 0x%"PRIx64,
1339                                 evsel->attr.type,
1340                                 (u64)evsel->attr.config,
1341                                 (u64)evsel->attr.config1,
1342                                 (u64)evsel->attr.config2);
1343
1344                 fprintf(fp, ", excl_usr = %d, excl_kern = %d",
1345                                 evsel->attr.exclude_user,
1346                                 evsel->attr.exclude_kernel);
1347
1348                 fprintf(fp, ", excl_host = %d, excl_guest = %d",
1349                                 evsel->attr.exclude_host,
1350                                 evsel->attr.exclude_guest);
1351
1352                 fprintf(fp, ", precise_ip = %d", evsel->attr.precise_ip);
1353
1354                 fprintf(fp, ", attr_mmap2 = %d", evsel->attr.mmap2);
1355                 fprintf(fp, ", attr_mmap  = %d", evsel->attr.mmap);
1356                 fprintf(fp, ", attr_mmap_data = %d", evsel->attr.mmap_data);
1357                 if (evsel->ids) {
1358                         fprintf(fp, ", id = {");
1359                         for (j = 0, id = evsel->id; j < evsel->ids; j++, id++) {
1360                                 if (j)
1361                                         fputc(',', fp);
1362                                 fprintf(fp, " %"PRIu64, *id);
1363                         }
1364                         fprintf(fp, " }");
1365                 }
1366
1367                 fputc('\n', fp);
1368         }
1369
1370         free_event_desc(events);
1371 }
1372
1373 static void print_total_mem(struct perf_header *ph, int fd __maybe_unused,
1374                             FILE *fp)
1375 {
1376         fprintf(fp, "# total memory : %Lu kB\n", ph->env.total_mem);
1377 }
1378
1379 static void print_numa_topology(struct perf_header *ph, int fd __maybe_unused,
1380                                 FILE *fp)
1381 {
1382         u32 nr, c, i;
1383         char *str, *tmp;
1384         uint64_t mem_total, mem_free;
1385
1386         /* nr nodes */
1387         nr = ph->env.nr_numa_nodes;
1388         str = ph->env.numa_nodes;
1389
1390         for (i = 0; i < nr; i++) {
1391                 /* node number */
1392                 c = strtoul(str, &tmp, 0);
1393                 if (*tmp != ':')
1394                         goto error;
1395
1396                 str = tmp + 1;
1397                 mem_total = strtoull(str, &tmp, 0);
1398                 if (*tmp != ':')
1399                         goto error;
1400
1401                 str = tmp + 1;
1402                 mem_free = strtoull(str, &tmp, 0);
1403                 if (*tmp != ':')
1404                         goto error;
1405
1406                 fprintf(fp, "# node%u meminfo  : total = %"PRIu64" kB,"
1407                             " free = %"PRIu64" kB\n",
1408                         c, mem_total, mem_free);
1409
1410                 str = tmp + 1;
1411                 fprintf(fp, "# node%u cpu list : %s\n", c, str);
1412
1413                 str += strlen(str) + 1;
1414         }
1415         return;
1416 error:
1417         fprintf(fp, "# numa topology : not available\n");
1418 }
1419
1420 static void print_cpuid(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
1421 {
1422         fprintf(fp, "# cpuid : %s\n", ph->env.cpuid);
1423 }
1424
1425 static void print_branch_stack(struct perf_header *ph __maybe_unused,
1426                                int fd __maybe_unused, FILE *fp)
1427 {
1428         fprintf(fp, "# contains samples with branch stack\n");
1429 }
1430
1431 static void print_pmu_mappings(struct perf_header *ph, int fd __maybe_unused,
1432                                FILE *fp)
1433 {
1434         const char *delimiter = "# pmu mappings: ";
1435         char *str, *tmp;
1436         u32 pmu_num;
1437         u32 type;
1438
1439         pmu_num = ph->env.nr_pmu_mappings;
1440         if (!pmu_num) {
1441                 fprintf(fp, "# pmu mappings: not available\n");
1442                 return;
1443         }
1444
1445         str = ph->env.pmu_mappings;
1446
1447         while (pmu_num) {
1448                 type = strtoul(str, &tmp, 0);
1449                 if (*tmp != ':')
1450                         goto error;
1451
1452                 str = tmp + 1;
1453                 fprintf(fp, "%s%s = %" PRIu32, delimiter, str, type);
1454
1455                 delimiter = ", ";
1456                 str += strlen(str) + 1;
1457                 pmu_num--;
1458         }
1459
1460         fprintf(fp, "\n");
1461
1462         if (!pmu_num)
1463                 return;
1464 error:
1465         fprintf(fp, "# pmu mappings: unable to read\n");
1466 }
1467
1468 static void print_group_desc(struct perf_header *ph, int fd __maybe_unused,
1469                              FILE *fp)
1470 {
1471         struct perf_session *session;
1472         struct perf_evsel *evsel;
1473         u32 nr = 0;
1474
1475         session = container_of(ph, struct perf_session, header);
1476
1477         list_for_each_entry(evsel, &session->evlist->entries, node) {
1478                 if (perf_evsel__is_group_leader(evsel) &&
1479                     evsel->nr_members > 1) {
1480                         fprintf(fp, "# group: %s{%s", evsel->group_name ?: "",
1481                                 perf_evsel__name(evsel));
1482
1483                         nr = evsel->nr_members - 1;
1484                 } else if (nr) {
1485                         fprintf(fp, ",%s", perf_evsel__name(evsel));
1486
1487                         if (--nr == 0)
1488                                 fprintf(fp, "}\n");
1489                 }
1490         }
1491 }
1492
1493 static int __event_process_build_id(struct build_id_event *bev,
1494                                     char *filename,
1495                                     struct perf_session *session)
1496 {
1497         int err = -1;
1498         struct list_head *head;
1499         struct machine *machine;
1500         u16 misc;
1501         struct dso *dso;
1502         enum dso_kernel_type dso_type;
1503
1504         machine = perf_session__findnew_machine(session, bev->pid);
1505         if (!machine)
1506                 goto out;
1507
1508         misc = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
1509
1510         switch (misc) {
1511         case PERF_RECORD_MISC_KERNEL:
1512                 dso_type = DSO_TYPE_KERNEL;
1513                 head = &machine->kernel_dsos;
1514                 break;
1515         case PERF_RECORD_MISC_GUEST_KERNEL:
1516                 dso_type = DSO_TYPE_GUEST_KERNEL;
1517                 head = &machine->kernel_dsos;
1518                 break;
1519         case PERF_RECORD_MISC_USER:
1520         case PERF_RECORD_MISC_GUEST_USER:
1521                 dso_type = DSO_TYPE_USER;
1522                 head = &machine->user_dsos;
1523                 break;
1524         default:
1525                 goto out;
1526         }
1527
1528         dso = __dsos__findnew(head, filename);
1529         if (dso != NULL) {
1530                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1531
1532                 dso__set_build_id(dso, &bev->build_id);
1533
1534                 if (filename[0] == '[')
1535                         dso->kernel = dso_type;
1536
1537                 build_id__sprintf(dso->build_id, sizeof(dso->build_id),
1538                                   sbuild_id);
1539                 pr_debug("build id event received for %s: %s\n",
1540                          dso->long_name, sbuild_id);
1541         }
1542
1543         err = 0;
1544 out:
1545         return err;
1546 }
1547
1548 static int perf_header__read_build_ids_abi_quirk(struct perf_header *header,
1549                                                  int input, u64 offset, u64 size)
1550 {
1551         struct perf_session *session = container_of(header, struct perf_session, header);
1552         struct {
1553                 struct perf_event_header   header;
1554                 u8                         build_id[PERF_ALIGN(BUILD_ID_SIZE, sizeof(u64))];
1555                 char                       filename[0];
1556         } old_bev;
1557         struct build_id_event bev;
1558         char filename[PATH_MAX];
1559         u64 limit = offset + size;
1560
1561         while (offset < limit) {
1562                 ssize_t len;
1563
1564                 if (readn(input, &old_bev, sizeof(old_bev)) != sizeof(old_bev))
1565                         return -1;
1566
1567                 if (header->needs_swap)
1568                         perf_event_header__bswap(&old_bev.header);
1569
1570                 len = old_bev.header.size - sizeof(old_bev);
1571                 if (readn(input, filename, len) != len)
1572                         return -1;
1573
1574                 bev.header = old_bev.header;
1575
1576                 /*
1577                  * As the pid is the missing value, we need to fill
1578                  * it properly. The header.misc value give us nice hint.
1579                  */
1580                 bev.pid = HOST_KERNEL_ID;
1581                 if (bev.header.misc == PERF_RECORD_MISC_GUEST_USER ||
1582                     bev.header.misc == PERF_RECORD_MISC_GUEST_KERNEL)
1583                         bev.pid = DEFAULT_GUEST_KERNEL_ID;
1584
1585                 memcpy(bev.build_id, old_bev.build_id, sizeof(bev.build_id));
1586                 __event_process_build_id(&bev, filename, session);
1587
1588                 offset += bev.header.size;
1589         }
1590
1591         return 0;
1592 }
1593
1594 static int perf_header__read_build_ids(struct perf_header *header,
1595                                        int input, u64 offset, u64 size)
1596 {
1597         struct perf_session *session = container_of(header, struct perf_session, header);
1598         struct build_id_event bev;
1599         char filename[PATH_MAX];
1600         u64 limit = offset + size, orig_offset = offset;
1601         int err = -1;
1602
1603         while (offset < limit) {
1604                 ssize_t len;
1605
1606                 if (readn(input, &bev, sizeof(bev)) != sizeof(bev))
1607                         goto out;
1608
1609                 if (header->needs_swap)
1610                         perf_event_header__bswap(&bev.header);
1611
1612                 len = bev.header.size - sizeof(bev);
1613                 if (readn(input, filename, len) != len)
1614                         goto out;
1615                 /*
1616                  * The a1645ce1 changeset:
1617                  *
1618                  * "perf: 'perf kvm' tool for monitoring guest performance from host"
1619                  *
1620                  * Added a field to struct build_id_event that broke the file
1621                  * format.
1622                  *
1623                  * Since the kernel build-id is the first entry, process the
1624                  * table using the old format if the well known
1625                  * '[kernel.kallsyms]' string for the kernel build-id has the
1626                  * first 4 characters chopped off (where the pid_t sits).
1627                  */
1628                 if (memcmp(filename, "nel.kallsyms]", 13) == 0) {
1629                         if (lseek(input, orig_offset, SEEK_SET) == (off_t)-1)
1630                                 return -1;
1631                         return perf_header__read_build_ids_abi_quirk(header, input, offset, size);
1632                 }
1633
1634                 __event_process_build_id(&bev, filename, session);
1635
1636                 offset += bev.header.size;
1637         }
1638         err = 0;
1639 out:
1640         return err;
1641 }
1642
1643 static int process_tracing_data(struct perf_file_section *section __maybe_unused,
1644                                 struct perf_header *ph __maybe_unused,
1645                                 int fd, void *data)
1646 {
1647         ssize_t ret = trace_report(fd, data, false);
1648         return ret < 0 ? -1 : 0;
1649 }
1650
1651 static int process_build_id(struct perf_file_section *section,
1652                             struct perf_header *ph, int fd,
1653                             void *data __maybe_unused)
1654 {
1655         if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
1656                 pr_debug("Failed to read buildids, continuing...\n");
1657         return 0;
1658 }
1659
1660 static int process_hostname(struct perf_file_section *section __maybe_unused,
1661                             struct perf_header *ph, int fd,
1662                             void *data __maybe_unused)
1663 {
1664         ph->env.hostname = do_read_string(fd, ph);
1665         return ph->env.hostname ? 0 : -ENOMEM;
1666 }
1667
1668 static int process_osrelease(struct perf_file_section *section __maybe_unused,
1669                              struct perf_header *ph, int fd,
1670                              void *data __maybe_unused)
1671 {
1672         ph->env.os_release = do_read_string(fd, ph);
1673         return ph->env.os_release ? 0 : -ENOMEM;
1674 }
1675
1676 static int process_version(struct perf_file_section *section __maybe_unused,
1677                            struct perf_header *ph, int fd,
1678                            void *data __maybe_unused)
1679 {
1680         ph->env.version = do_read_string(fd, ph);
1681         return ph->env.version ? 0 : -ENOMEM;
1682 }
1683
1684 static int process_arch(struct perf_file_section *section __maybe_unused,
1685                         struct perf_header *ph, int fd,
1686                         void *data __maybe_unused)
1687 {
1688         ph->env.arch = do_read_string(fd, ph);
1689         return ph->env.arch ? 0 : -ENOMEM;
1690 }
1691
1692 static int process_nrcpus(struct perf_file_section *section __maybe_unused,
1693                           struct perf_header *ph, int fd,
1694                           void *data __maybe_unused)
1695 {
1696         size_t ret;
1697         u32 nr;
1698
1699         ret = readn(fd, &nr, sizeof(nr));
1700         if (ret != sizeof(nr))
1701                 return -1;
1702
1703         if (ph->needs_swap)
1704                 nr = bswap_32(nr);
1705
1706         ph->env.nr_cpus_online = nr;
1707
1708         ret = readn(fd, &nr, sizeof(nr));
1709         if (ret != sizeof(nr))
1710                 return -1;
1711
1712         if (ph->needs_swap)
1713                 nr = bswap_32(nr);
1714
1715         ph->env.nr_cpus_avail = nr;
1716         return 0;
1717 }
1718
1719 static int process_cpudesc(struct perf_file_section *section __maybe_unused,
1720                            struct perf_header *ph, int fd,
1721                            void *data __maybe_unused)
1722 {
1723         ph->env.cpu_desc = do_read_string(fd, ph);
1724         return ph->env.cpu_desc ? 0 : -ENOMEM;
1725 }
1726
1727 static int process_cpuid(struct perf_file_section *section __maybe_unused,
1728                          struct perf_header *ph,  int fd,
1729                          void *data __maybe_unused)
1730 {
1731         ph->env.cpuid = do_read_string(fd, ph);
1732         return ph->env.cpuid ? 0 : -ENOMEM;
1733 }
1734
1735 static int process_total_mem(struct perf_file_section *section __maybe_unused,
1736                              struct perf_header *ph, int fd,
1737                              void *data __maybe_unused)
1738 {
1739         uint64_t mem;
1740         size_t ret;
1741
1742         ret = readn(fd, &mem, sizeof(mem));
1743         if (ret != sizeof(mem))
1744                 return -1;
1745
1746         if (ph->needs_swap)
1747                 mem = bswap_64(mem);
1748
1749         ph->env.total_mem = mem;
1750         return 0;
1751 }
1752
1753 static struct perf_evsel *
1754 perf_evlist__find_by_index(struct perf_evlist *evlist, int idx)
1755 {
1756         struct perf_evsel *evsel;
1757
1758         list_for_each_entry(evsel, &evlist->entries, node) {
1759                 if (evsel->idx == idx)
1760                         return evsel;
1761         }
1762
1763         return NULL;
1764 }
1765
1766 static void
1767 perf_evlist__set_event_name(struct perf_evlist *evlist,
1768                             struct perf_evsel *event)
1769 {
1770         struct perf_evsel *evsel;
1771
1772         if (!event->name)
1773                 return;
1774
1775         evsel = perf_evlist__find_by_index(evlist, event->idx);
1776         if (!evsel)
1777                 return;
1778
1779         if (evsel->name)
1780                 return;
1781
1782         evsel->name = strdup(event->name);
1783 }
1784
1785 static int
1786 process_event_desc(struct perf_file_section *section __maybe_unused,
1787                    struct perf_header *header, int fd,
1788                    void *data __maybe_unused)
1789 {
1790         struct perf_session *session;
1791         struct perf_evsel *evsel, *events = read_event_desc(header, fd);
1792
1793         if (!events)
1794                 return 0;
1795
1796         session = container_of(header, struct perf_session, header);
1797         for (evsel = events; evsel->attr.size; evsel++)
1798                 perf_evlist__set_event_name(session->evlist, evsel);
1799
1800         free_event_desc(events);
1801
1802         return 0;
1803 }
1804
1805 static int process_cmdline(struct perf_file_section *section __maybe_unused,
1806                            struct perf_header *ph, int fd,
1807                            void *data __maybe_unused)
1808 {
1809         size_t ret;
1810         char *str;
1811         u32 nr, i;
1812         struct strbuf sb;
1813
1814         ret = readn(fd, &nr, sizeof(nr));
1815         if (ret != sizeof(nr))
1816                 return -1;
1817
1818         if (ph->needs_swap)
1819                 nr = bswap_32(nr);
1820
1821         ph->env.nr_cmdline = nr;
1822         strbuf_init(&sb, 128);
1823
1824         for (i = 0; i < nr; i++) {
1825                 str = do_read_string(fd, ph);
1826                 if (!str)
1827                         goto error;
1828
1829                 /* include a NULL character at the end */
1830                 strbuf_add(&sb, str, strlen(str) + 1);
1831                 free(str);
1832         }
1833         ph->env.cmdline = strbuf_detach(&sb, NULL);
1834         return 0;
1835
1836 error:
1837         strbuf_release(&sb);
1838         return -1;
1839 }
1840
1841 static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
1842                                 struct perf_header *ph, int fd,
1843                                 void *data __maybe_unused)
1844 {
1845         size_t ret;
1846         u32 nr, i;
1847         char *str;
1848         struct strbuf sb;
1849
1850         ret = readn(fd, &nr, sizeof(nr));
1851         if (ret != sizeof(nr))
1852                 return -1;
1853
1854         if (ph->needs_swap)
1855                 nr = bswap_32(nr);
1856
1857         ph->env.nr_sibling_cores = nr;
1858         strbuf_init(&sb, 128);
1859
1860         for (i = 0; i < nr; i++) {
1861                 str = do_read_string(fd, ph);
1862                 if (!str)
1863                         goto error;
1864
1865                 /* include a NULL character at the end */
1866                 strbuf_add(&sb, str, strlen(str) + 1);
1867                 free(str);
1868         }
1869         ph->env.sibling_cores = strbuf_detach(&sb, NULL);
1870
1871         ret = readn(fd, &nr, sizeof(nr));
1872         if (ret != sizeof(nr))
1873                 return -1;
1874
1875         if (ph->needs_swap)
1876                 nr = bswap_32(nr);
1877
1878         ph->env.nr_sibling_threads = nr;
1879
1880         for (i = 0; i < nr; i++) {
1881                 str = do_read_string(fd, ph);
1882                 if (!str)
1883                         goto error;
1884
1885                 /* include a NULL character at the end */
1886                 strbuf_add(&sb, str, strlen(str) + 1);
1887                 free(str);
1888         }
1889         ph->env.sibling_threads = strbuf_detach(&sb, NULL);
1890         return 0;
1891
1892 error:
1893         strbuf_release(&sb);
1894         return -1;
1895 }
1896
1897 static int process_numa_topology(struct perf_file_section *section __maybe_unused,
1898                                  struct perf_header *ph, int fd,
1899                                  void *data __maybe_unused)
1900 {
1901         size_t ret;
1902         u32 nr, node, i;
1903         char *str;
1904         uint64_t mem_total, mem_free;
1905         struct strbuf sb;
1906
1907         /* nr nodes */
1908         ret = readn(fd, &nr, sizeof(nr));
1909         if (ret != sizeof(nr))
1910                 goto error;
1911
1912         if (ph->needs_swap)
1913                 nr = bswap_32(nr);
1914
1915         ph->env.nr_numa_nodes = nr;
1916         strbuf_init(&sb, 256);
1917
1918         for (i = 0; i < nr; i++) {
1919                 /* node number */
1920                 ret = readn(fd, &node, sizeof(node));
1921                 if (ret != sizeof(node))
1922                         goto error;
1923
1924                 ret = readn(fd, &mem_total, sizeof(u64));
1925                 if (ret != sizeof(u64))
1926                         goto error;
1927
1928                 ret = readn(fd, &mem_free, sizeof(u64));
1929                 if (ret != sizeof(u64))
1930                         goto error;
1931
1932                 if (ph->needs_swap) {
1933                         node = bswap_32(node);
1934                         mem_total = bswap_64(mem_total);
1935                         mem_free = bswap_64(mem_free);
1936                 }
1937
1938                 strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
1939                             node, mem_total, mem_free);
1940
1941                 str = do_read_string(fd, ph);
1942                 if (!str)
1943                         goto error;
1944
1945                 /* include a NULL character at the end */
1946                 strbuf_add(&sb, str, strlen(str) + 1);
1947                 free(str);
1948         }
1949         ph->env.numa_nodes = strbuf_detach(&sb, NULL);
1950         return 0;
1951
1952 error:
1953         strbuf_release(&sb);
1954         return -1;
1955 }
1956
1957 static int process_pmu_mappings(struct perf_file_section *section __maybe_unused,
1958                                 struct perf_header *ph, int fd,
1959                                 void *data __maybe_unused)
1960 {
1961         size_t ret;
1962         char *name;
1963         u32 pmu_num;
1964         u32 type;
1965         struct strbuf sb;
1966
1967         ret = readn(fd, &pmu_num, sizeof(pmu_num));
1968         if (ret != sizeof(pmu_num))
1969                 return -1;
1970
1971         if (ph->needs_swap)
1972                 pmu_num = bswap_32(pmu_num);
1973
1974         if (!pmu_num) {
1975                 pr_debug("pmu mappings not available\n");
1976                 return 0;
1977         }
1978
1979         ph->env.nr_pmu_mappings = pmu_num;
1980         strbuf_init(&sb, 128);
1981
1982         while (pmu_num) {
1983                 if (readn(fd, &type, sizeof(type)) != sizeof(type))
1984                         goto error;
1985                 if (ph->needs_swap)
1986                         type = bswap_32(type);
1987
1988                 name = do_read_string(fd, ph);
1989                 if (!name)
1990                         goto error;
1991
1992                 strbuf_addf(&sb, "%u:%s", type, name);
1993                 /* include a NULL character at the end */
1994                 strbuf_add(&sb, "", 1);
1995
1996                 free(name);
1997                 pmu_num--;
1998         }
1999         ph->env.pmu_mappings = strbuf_detach(&sb, NULL);
2000         return 0;
2001
2002 error:
2003         strbuf_release(&sb);
2004         return -1;
2005 }
2006
2007 static int process_group_desc(struct perf_file_section *section __maybe_unused,
2008                               struct perf_header *ph, int fd,
2009                               void *data __maybe_unused)
2010 {
2011         size_t ret = -1;
2012         u32 i, nr, nr_groups;
2013         struct perf_session *session;
2014         struct perf_evsel *evsel, *leader = NULL;
2015         struct group_desc {
2016                 char *name;
2017                 u32 leader_idx;
2018                 u32 nr_members;
2019         } *desc;
2020
2021         if (readn(fd, &nr_groups, sizeof(nr_groups)) != sizeof(nr_groups))
2022                 return -1;
2023
2024         if (ph->needs_swap)
2025                 nr_groups = bswap_32(nr_groups);
2026
2027         ph->env.nr_groups = nr_groups;
2028         if (!nr_groups) {
2029                 pr_debug("group desc not available\n");
2030                 return 0;
2031         }
2032
2033         desc = calloc(nr_groups, sizeof(*desc));
2034         if (!desc)
2035                 return -1;
2036
2037         for (i = 0; i < nr_groups; i++) {
2038                 desc[i].name = do_read_string(fd, ph);
2039                 if (!desc[i].name)
2040                         goto out_free;
2041
2042                 if (readn(fd, &desc[i].leader_idx, sizeof(u32)) != sizeof(u32))
2043                         goto out_free;
2044
2045                 if (readn(fd, &desc[i].nr_members, sizeof(u32)) != sizeof(u32))
2046                         goto out_free;
2047
2048                 if (ph->needs_swap) {
2049                         desc[i].leader_idx = bswap_32(desc[i].leader_idx);
2050                         desc[i].nr_members = bswap_32(desc[i].nr_members);
2051                 }
2052         }
2053
2054         /*
2055          * Rebuild group relationship based on the group_desc
2056          */
2057         session = container_of(ph, struct perf_session, header);
2058         session->evlist->nr_groups = nr_groups;
2059
2060         i = nr = 0;
2061         list_for_each_entry(evsel, &session->evlist->entries, node) {
2062                 if (evsel->idx == (int) desc[i].leader_idx) {
2063                         evsel->leader = evsel;
2064                         /* {anon_group} is a dummy name */
2065                         if (strcmp(desc[i].name, "{anon_group}"))
2066                                 evsel->group_name = desc[i].name;
2067                         evsel->nr_members = desc[i].nr_members;
2068
2069                         if (i >= nr_groups || nr > 0) {
2070                                 pr_debug("invalid group desc\n");
2071                                 goto out_free;
2072                         }
2073
2074                         leader = evsel;
2075                         nr = evsel->nr_members - 1;
2076                         i++;
2077                 } else if (nr) {
2078                         /* This is a group member */
2079                         evsel->leader = leader;
2080
2081                         nr--;
2082                 }
2083         }
2084
2085         if (i != nr_groups || nr != 0) {
2086                 pr_debug("invalid group desc\n");
2087                 goto out_free;
2088         }
2089
2090         ret = 0;
2091 out_free:
2092         while ((int) --i >= 0)
2093                 free(desc[i].name);
2094         free(desc);
2095
2096         return ret;
2097 }
2098
2099 struct feature_ops {
2100         int (*write)(int fd, struct perf_header *h, struct perf_evlist *evlist);
2101         void (*print)(struct perf_header *h, int fd, FILE *fp);
2102         int (*process)(struct perf_file_section *section,
2103                        struct perf_header *h, int fd, void *data);
2104         const char *name;
2105         bool full_only;
2106 };
2107
2108 #define FEAT_OPA(n, func) \
2109         [n] = { .name = #n, .write = write_##func, .print = print_##func }
2110 #define FEAT_OPP(n, func) \
2111         [n] = { .name = #n, .write = write_##func, .print = print_##func, \
2112                 .process = process_##func }
2113 #define FEAT_OPF(n, func) \
2114         [n] = { .name = #n, .write = write_##func, .print = print_##func, \
2115                 .process = process_##func, .full_only = true }
2116
2117 /* feature_ops not implemented: */
2118 #define print_tracing_data      NULL
2119 #define print_build_id          NULL
2120
2121 static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
2122         FEAT_OPP(HEADER_TRACING_DATA,   tracing_data),
2123         FEAT_OPP(HEADER_BUILD_ID,       build_id),
2124         FEAT_OPP(HEADER_HOSTNAME,       hostname),
2125         FEAT_OPP(HEADER_OSRELEASE,      osrelease),
2126         FEAT_OPP(HEADER_VERSION,        version),
2127         FEAT_OPP(HEADER_ARCH,           arch),
2128         FEAT_OPP(HEADER_NRCPUS,         nrcpus),
2129         FEAT_OPP(HEADER_CPUDESC,        cpudesc),
2130         FEAT_OPP(HEADER_CPUID,          cpuid),
2131         FEAT_OPP(HEADER_TOTAL_MEM,      total_mem),
2132         FEAT_OPP(HEADER_EVENT_DESC,     event_desc),
2133         FEAT_OPP(HEADER_CMDLINE,        cmdline),
2134         FEAT_OPF(HEADER_CPU_TOPOLOGY,   cpu_topology),
2135         FEAT_OPF(HEADER_NUMA_TOPOLOGY,  numa_topology),
2136         FEAT_OPA(HEADER_BRANCH_STACK,   branch_stack),
2137         FEAT_OPP(HEADER_PMU_MAPPINGS,   pmu_mappings),
2138         FEAT_OPP(HEADER_GROUP_DESC,     group_desc),
2139 };
2140
2141 struct header_print_data {
2142         FILE *fp;
2143         bool full; /* extended list of headers */
2144 };
2145
2146 static int perf_file_section__fprintf_info(struct perf_file_section *section,
2147                                            struct perf_header *ph,
2148                                            int feat, int fd, void *data)
2149 {
2150         struct header_print_data *hd = data;
2151
2152         if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
2153                 pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
2154                                 "%d, continuing...\n", section->offset, feat);
2155                 return 0;
2156         }
2157         if (feat >= HEADER_LAST_FEATURE) {
2158                 pr_warning("unknown feature %d\n", feat);
2159                 return 0;
2160         }
2161         if (!feat_ops[feat].print)
2162                 return 0;
2163
2164         if (!feat_ops[feat].full_only || hd->full)
2165                 feat_ops[feat].print(ph, fd, hd->fp);
2166         else
2167                 fprintf(hd->fp, "# %s info available, use -I to display\n",
2168                         feat_ops[feat].name);
2169
2170         return 0;
2171 }
2172
2173 int perf_header__fprintf_info(struct perf_session *session, FILE *fp, bool full)
2174 {
2175         struct header_print_data hd;
2176         struct perf_header *header = &session->header;
2177         int fd = session->fd;
2178         hd.fp = fp;
2179         hd.full = full;
2180
2181         perf_header__process_sections(header, fd, &hd,
2182                                       perf_file_section__fprintf_info);
2183         return 0;
2184 }
2185
2186 static int do_write_feat(int fd, struct perf_header *h, int type,
2187                          struct perf_file_section **p,
2188                          struct perf_evlist *evlist)
2189 {
2190         int err;
2191         int ret = 0;
2192
2193         if (perf_header__has_feat(h, type)) {
2194                 if (!feat_ops[type].write)
2195                         return -1;
2196
2197                 (*p)->offset = lseek(fd, 0, SEEK_CUR);
2198
2199                 err = feat_ops[type].write(fd, h, evlist);
2200                 if (err < 0) {
2201                         pr_debug("failed to write feature %d\n", type);
2202
2203                         /* undo anything written */
2204                         lseek(fd, (*p)->offset, SEEK_SET);
2205
2206                         return -1;
2207                 }
2208                 (*p)->size = lseek(fd, 0, SEEK_CUR) - (*p)->offset;
2209                 (*p)++;
2210         }
2211         return ret;
2212 }
2213
2214 static int perf_header__adds_write(struct perf_header *header,
2215                                    struct perf_evlist *evlist, int fd)
2216 {
2217         int nr_sections;
2218         struct perf_file_section *feat_sec, *p;
2219         int sec_size;
2220         u64 sec_start;
2221         int feat;
2222         int err;
2223
2224         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
2225         if (!nr_sections)
2226                 return 0;
2227
2228         feat_sec = p = calloc(nr_sections, sizeof(*feat_sec));
2229         if (feat_sec == NULL)
2230                 return -ENOMEM;
2231
2232         sec_size = sizeof(*feat_sec) * nr_sections;
2233
2234         sec_start = header->feat_offset;
2235         lseek(fd, sec_start + sec_size, SEEK_SET);
2236
2237         for_each_set_bit(feat, header->adds_features, HEADER_FEAT_BITS) {
2238                 if (do_write_feat(fd, header, feat, &p, evlist))
2239                         perf_header__clear_feat(header, feat);
2240         }
2241
2242         lseek(fd, sec_start, SEEK_SET);
2243         /*
2244          * may write more than needed due to dropped feature, but
2245          * this is okay, reader will skip the mising entries
2246          */
2247         err = do_write(fd, feat_sec, sec_size);
2248         if (err < 0)
2249                 pr_debug("failed to write feature section\n");
2250         free(feat_sec);
2251         return err;
2252 }
2253
2254 int perf_header__write_pipe(int fd)
2255 {
2256         struct perf_pipe_file_header f_header;
2257         int err;
2258
2259         f_header = (struct perf_pipe_file_header){
2260                 .magic     = PERF_MAGIC,
2261                 .size      = sizeof(f_header),
2262         };
2263
2264         err = do_write(fd, &f_header, sizeof(f_header));
2265         if (err < 0) {
2266                 pr_debug("failed to write perf pipe header\n");
2267                 return err;
2268         }
2269
2270         return 0;
2271 }
2272
2273 int perf_session__write_header(struct perf_session *session,
2274                                struct perf_evlist *evlist,
2275                                int fd, bool at_exit)
2276 {
2277         struct perf_file_header f_header;
2278         struct perf_file_attr   f_attr;
2279         struct perf_header *header = &session->header;
2280         struct perf_evsel *evsel;
2281         u64 attr_offset;
2282         int err;
2283
2284         lseek(fd, sizeof(f_header), SEEK_SET);
2285
2286         list_for_each_entry(evsel, &evlist->entries, node) {
2287                 evsel->id_offset = lseek(fd, 0, SEEK_CUR);
2288                 err = do_write(fd, evsel->id, evsel->ids * sizeof(u64));
2289                 if (err < 0) {
2290                         pr_debug("failed to write perf header\n");
2291                         return err;
2292                 }
2293         }
2294
2295         attr_offset = lseek(fd, 0, SEEK_CUR);
2296
2297         list_for_each_entry(evsel, &evlist->entries, node) {
2298                 f_attr = (struct perf_file_attr){
2299                         .attr = evsel->attr,
2300                         .ids  = {
2301                                 .offset = evsel->id_offset,
2302                                 .size   = evsel->ids * sizeof(u64),
2303                         }
2304                 };
2305                 err = do_write(fd, &f_attr, sizeof(f_attr));
2306                 if (err < 0) {
2307                         pr_debug("failed to write perf header attribute\n");
2308                         return err;
2309                 }
2310         }
2311
2312         header->data_offset = lseek(fd, 0, SEEK_CUR);
2313         header->feat_offset = header->data_offset + header->data_size;
2314
2315         if (at_exit) {
2316                 err = perf_header__adds_write(header, evlist, fd);
2317                 if (err < 0)
2318                         return err;
2319         }
2320
2321         f_header = (struct perf_file_header){
2322                 .magic     = PERF_MAGIC,
2323                 .size      = sizeof(f_header),
2324                 .attr_size = sizeof(f_attr),
2325                 .attrs = {
2326                         .offset = attr_offset,
2327                         .size   = evlist->nr_entries * sizeof(f_attr),
2328                 },
2329                 .data = {
2330                         .offset = header->data_offset,
2331                         .size   = header->data_size,
2332                 },
2333                 /* event_types is ignored, store zeros */
2334         };
2335
2336         memcpy(&f_header.adds_features, &header->adds_features, sizeof(header->adds_features));
2337
2338         lseek(fd, 0, SEEK_SET);
2339         err = do_write(fd, &f_header, sizeof(f_header));
2340         if (err < 0) {
2341                 pr_debug("failed to write perf header\n");
2342                 return err;
2343         }
2344         lseek(fd, header->data_offset + header->data_size, SEEK_SET);
2345
2346         return 0;
2347 }
2348
2349 static int perf_header__getbuffer64(struct perf_header *header,
2350                                     int fd, void *buf, size_t size)
2351 {
2352         if (readn(fd, buf, size) <= 0)
2353                 return -1;
2354
2355         if (header->needs_swap)
2356                 mem_bswap_64(buf, size);
2357
2358         return 0;
2359 }
2360
2361 int perf_header__process_sections(struct perf_header *header, int fd,
2362                                   void *data,
2363                                   int (*process)(struct perf_file_section *section,
2364                                                  struct perf_header *ph,
2365                                                  int feat, int fd, void *data))
2366 {
2367         struct perf_file_section *feat_sec, *sec;
2368         int nr_sections;
2369         int sec_size;
2370         int feat;
2371         int err;
2372
2373         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
2374         if (!nr_sections)
2375                 return 0;
2376
2377         feat_sec = sec = calloc(nr_sections, sizeof(*feat_sec));
2378         if (!feat_sec)
2379                 return -1;
2380
2381         sec_size = sizeof(*feat_sec) * nr_sections;
2382
2383         lseek(fd, header->feat_offset, SEEK_SET);
2384
2385         err = perf_header__getbuffer64(header, fd, feat_sec, sec_size);
2386         if (err < 0)
2387                 goto out_free;
2388
2389         for_each_set_bit(feat, header->adds_features, HEADER_LAST_FEATURE) {
2390                 err = process(sec++, header, feat, fd, data);
2391                 if (err < 0)
2392                         goto out_free;
2393         }
2394         err = 0;
2395 out_free:
2396         free(feat_sec);
2397         return err;
2398 }
2399
2400 static const int attr_file_abi_sizes[] = {
2401         [0] = PERF_ATTR_SIZE_VER0,
2402         [1] = PERF_ATTR_SIZE_VER1,
2403         [2] = PERF_ATTR_SIZE_VER2,
2404         [3] = PERF_ATTR_SIZE_VER3,
2405         0,
2406 };
2407
2408 /*
2409  * In the legacy file format, the magic number is not used to encode endianness.
2410  * hdr_sz was used to encode endianness. But given that hdr_sz can vary based
2411  * on ABI revisions, we need to try all combinations for all endianness to
2412  * detect the endianness.
2413  */
2414 static int try_all_file_abis(uint64_t hdr_sz, struct perf_header *ph)
2415 {
2416         uint64_t ref_size, attr_size;
2417         int i;
2418
2419         for (i = 0 ; attr_file_abi_sizes[i]; i++) {
2420                 ref_size = attr_file_abi_sizes[i]
2421                          + sizeof(struct perf_file_section);
2422                 if (hdr_sz != ref_size) {
2423                         attr_size = bswap_64(hdr_sz);
2424                         if (attr_size != ref_size)
2425                                 continue;
2426
2427                         ph->needs_swap = true;
2428                 }
2429                 pr_debug("ABI%d perf.data file detected, need_swap=%d\n",
2430                          i,
2431                          ph->needs_swap);
2432                 return 0;
2433         }
2434         /* could not determine endianness */
2435         return -1;
2436 }
2437
2438 #define PERF_PIPE_HDR_VER0      16
2439
2440 static const size_t attr_pipe_abi_sizes[] = {
2441         [0] = PERF_PIPE_HDR_VER0,
2442         0,
2443 };
2444
2445 /*
2446  * In the legacy pipe format, there is an implicit assumption that endiannesss
2447  * between host recording the samples, and host parsing the samples is the
2448  * same. This is not always the case given that the pipe output may always be
2449  * redirected into a file and analyzed on a different machine with possibly a
2450  * different endianness and perf_event ABI revsions in the perf tool itself.
2451  */
2452 static int try_all_pipe_abis(uint64_t hdr_sz, struct perf_header *ph)
2453 {
2454         u64 attr_size;
2455         int i;
2456
2457         for (i = 0 ; attr_pipe_abi_sizes[i]; i++) {
2458                 if (hdr_sz != attr_pipe_abi_sizes[i]) {
2459                         attr_size = bswap_64(hdr_sz);
2460                         if (attr_size != hdr_sz)
2461                                 continue;
2462
2463                         ph->needs_swap = true;
2464                 }
2465                 pr_debug("Pipe ABI%d perf.data file detected\n", i);
2466                 return 0;
2467         }
2468         return -1;
2469 }
2470
2471 bool is_perf_magic(u64 magic)
2472 {
2473         if (!memcmp(&magic, __perf_magic1, sizeof(magic))
2474                 || magic == __perf_magic2
2475                 || magic == __perf_magic2_sw)
2476                 return true;
2477
2478         return false;
2479 }
2480
2481 static int check_magic_endian(u64 magic, uint64_t hdr_sz,
2482                               bool is_pipe, struct perf_header *ph)
2483 {
2484         int ret;
2485
2486         /* check for legacy format */
2487         ret = memcmp(&magic, __perf_magic1, sizeof(magic));
2488         if (ret == 0) {
2489                 ph->version = PERF_HEADER_VERSION_1;
2490                 pr_debug("legacy perf.data format\n");
2491                 if (is_pipe)
2492                         return try_all_pipe_abis(hdr_sz, ph);
2493
2494                 return try_all_file_abis(hdr_sz, ph);
2495         }
2496         /*
2497          * the new magic number serves two purposes:
2498          * - unique number to identify actual perf.data files
2499          * - encode endianness of file
2500          */
2501
2502         /* check magic number with one endianness */
2503         if (magic == __perf_magic2)
2504                 return 0;
2505
2506         /* check magic number with opposite endianness */
2507         if (magic != __perf_magic2_sw)
2508                 return -1;
2509
2510         ph->needs_swap = true;
2511         ph->version = PERF_HEADER_VERSION_2;
2512
2513         return 0;
2514 }
2515
2516 int perf_file_header__read(struct perf_file_header *header,
2517                            struct perf_header *ph, int fd)
2518 {
2519         int ret;
2520
2521         lseek(fd, 0, SEEK_SET);
2522
2523         ret = readn(fd, header, sizeof(*header));
2524         if (ret <= 0)
2525                 return -1;
2526
2527         if (check_magic_endian(header->magic,
2528                                header->attr_size, false, ph) < 0) {
2529                 pr_debug("magic/endian check failed\n");
2530                 return -1;
2531         }
2532
2533         if (ph->needs_swap) {
2534                 mem_bswap_64(header, offsetof(struct perf_file_header,
2535                              adds_features));
2536         }
2537
2538         if (header->size != sizeof(*header)) {
2539                 /* Support the previous format */
2540                 if (header->size == offsetof(typeof(*header), adds_features))
2541                         bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
2542                 else
2543                         return -1;
2544         } else if (ph->needs_swap) {
2545                 /*
2546                  * feature bitmap is declared as an array of unsigned longs --
2547                  * not good since its size can differ between the host that
2548                  * generated the data file and the host analyzing the file.
2549                  *
2550                  * We need to handle endianness, but we don't know the size of
2551                  * the unsigned long where the file was generated. Take a best
2552                  * guess at determining it: try 64-bit swap first (ie., file
2553                  * created on a 64-bit host), and check if the hostname feature
2554                  * bit is set (this feature bit is forced on as of fbe96f2).
2555                  * If the bit is not, undo the 64-bit swap and try a 32-bit
2556                  * swap. If the hostname bit is still not set (e.g., older data
2557                  * file), punt and fallback to the original behavior --
2558                  * clearing all feature bits and setting buildid.
2559                  */
2560                 mem_bswap_64(&header->adds_features,
2561                             BITS_TO_U64(HEADER_FEAT_BITS));
2562
2563                 if (!test_bit(HEADER_HOSTNAME, header->adds_features)) {
2564                         /* unswap as u64 */
2565                         mem_bswap_64(&header->adds_features,
2566                                     BITS_TO_U64(HEADER_FEAT_BITS));
2567
2568                         /* unswap as u32 */
2569                         mem_bswap_32(&header->adds_features,
2570                                     BITS_TO_U32(HEADER_FEAT_BITS));
2571                 }
2572
2573                 if (!test_bit(HEADER_HOSTNAME, header->adds_features)) {
2574                         bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
2575                         set_bit(HEADER_BUILD_ID, header->adds_features);
2576                 }
2577         }
2578
2579         memcpy(&ph->adds_features, &header->adds_features,
2580                sizeof(ph->adds_features));
2581
2582         ph->data_offset  = header->data.offset;
2583         ph->data_size    = header->data.size;
2584         ph->feat_offset  = header->data.offset + header->data.size;
2585         return 0;
2586 }
2587
2588 static int perf_file_section__process(struct perf_file_section *section,
2589                                       struct perf_header *ph,
2590                                       int feat, int fd, void *data)
2591 {
2592         if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
2593                 pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
2594                           "%d, continuing...\n", section->offset, feat);
2595                 return 0;
2596         }
2597
2598         if (feat >= HEADER_LAST_FEATURE) {
2599                 pr_debug("unknown feature %d, continuing...\n", feat);
2600                 return 0;
2601         }
2602
2603         if (!feat_ops[feat].process)
2604                 return 0;
2605
2606         return feat_ops[feat].process(section, ph, fd, data);
2607 }
2608
2609 static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
2610                                        struct perf_header *ph, int fd,
2611                                        bool repipe)
2612 {
2613         int ret;
2614
2615         ret = readn(fd, header, sizeof(*header));
2616         if (ret <= 0)
2617                 return -1;
2618
2619         if (check_magic_endian(header->magic, header->size, true, ph) < 0) {
2620                 pr_debug("endian/magic failed\n");
2621                 return -1;
2622         }
2623
2624         if (ph->needs_swap)
2625                 header->size = bswap_64(header->size);
2626
2627         if (repipe && do_write(STDOUT_FILENO, header, sizeof(*header)) < 0)
2628                 return -1;
2629
2630         return 0;
2631 }
2632
2633 static int perf_header__read_pipe(struct perf_session *session)
2634 {
2635         struct perf_header *header = &session->header;
2636         struct perf_pipe_file_header f_header;
2637
2638         if (perf_file_header__read_pipe(&f_header, header, session->fd,
2639                                         session->repipe) < 0) {
2640                 pr_debug("incompatible file format\n");
2641                 return -EINVAL;
2642         }
2643
2644         return 0;
2645 }
2646
2647 static int read_attr(int fd, struct perf_header *ph,
2648                      struct perf_file_attr *f_attr)
2649 {
2650         struct perf_event_attr *attr = &f_attr->attr;
2651         size_t sz, left;
2652         size_t our_sz = sizeof(f_attr->attr);
2653         int ret;
2654
2655         memset(f_attr, 0, sizeof(*f_attr));
2656
2657         /* read minimal guaranteed structure */
2658         ret = readn(fd, attr, PERF_ATTR_SIZE_VER0);
2659         if (ret <= 0) {
2660                 pr_debug("cannot read %d bytes of header attr\n",
2661                          PERF_ATTR_SIZE_VER0);
2662                 return -1;
2663         }
2664
2665         /* on file perf_event_attr size */
2666         sz = attr->size;
2667
2668         if (ph->needs_swap)
2669                 sz = bswap_32(sz);
2670
2671         if (sz == 0) {
2672                 /* assume ABI0 */
2673                 sz =  PERF_ATTR_SIZE_VER0;
2674         } else if (sz > our_sz) {
2675                 pr_debug("file uses a more recent and unsupported ABI"
2676                          " (%zu bytes extra)\n", sz - our_sz);
2677                 return -1;
2678         }
2679         /* what we have not yet read and that we know about */
2680         left = sz - PERF_ATTR_SIZE_VER0;
2681         if (left) {
2682                 void *ptr = attr;
2683                 ptr += PERF_ATTR_SIZE_VER0;
2684
2685                 ret = readn(fd, ptr, left);
2686         }
2687         /* read perf_file_section, ids are read in caller */
2688         ret = readn(fd, &f_attr->ids, sizeof(f_attr->ids));
2689
2690         return ret <= 0 ? -1 : 0;
2691 }
2692
2693 static int perf_evsel__prepare_tracepoint_event(struct perf_evsel *evsel,
2694                                                 struct pevent *pevent)
2695 {
2696         struct event_format *event;
2697         char bf[128];
2698
2699         /* already prepared */
2700         if (evsel->tp_format)
2701                 return 0;
2702
2703         if (pevent == NULL) {
2704                 pr_debug("broken or missing trace data\n");
2705                 return -1;
2706         }
2707
2708         event = pevent_find_event(pevent, evsel->attr.config);
2709         if (event == NULL)
2710                 return -1;
2711
2712         if (!evsel->name) {
2713                 snprintf(bf, sizeof(bf), "%s:%s", event->system, event->name);
2714                 evsel->name = strdup(bf);
2715                 if (evsel->name == NULL)
2716                         return -1;
2717         }
2718
2719         evsel->tp_format = event;
2720         return 0;
2721 }
2722
2723 static int perf_evlist__prepare_tracepoint_events(struct perf_evlist *evlist,
2724                                                   struct pevent *pevent)
2725 {
2726         struct perf_evsel *pos;
2727
2728         list_for_each_entry(pos, &evlist->entries, node) {
2729                 if (pos->attr.type == PERF_TYPE_TRACEPOINT &&
2730                     perf_evsel__prepare_tracepoint_event(pos, pevent))
2731                         return -1;
2732         }
2733
2734         return 0;
2735 }
2736
2737 int perf_session__read_header(struct perf_session *session)
2738 {
2739         struct perf_header *header = &session->header;
2740         struct perf_file_header f_header;
2741         struct perf_file_attr   f_attr;
2742         u64                     f_id;
2743         int nr_attrs, nr_ids, i, j;
2744         int fd = session->fd;
2745
2746         session->evlist = perf_evlist__new();
2747         if (session->evlist == NULL)
2748                 return -ENOMEM;
2749
2750         if (session->fd_pipe)
2751                 return perf_header__read_pipe(session);
2752
2753         if (perf_file_header__read(&f_header, header, fd) < 0)
2754                 return -EINVAL;
2755
2756         nr_attrs = f_header.attrs.size / f_header.attr_size;
2757         lseek(fd, f_header.attrs.offset, SEEK_SET);
2758
2759         for (i = 0; i < nr_attrs; i++) {
2760                 struct perf_evsel *evsel;
2761                 off_t tmp;
2762
2763                 if (read_attr(fd, header, &f_attr) < 0)
2764                         goto out_errno;
2765
2766                 if (header->needs_swap)
2767                         perf_event__attr_swap(&f_attr.attr);
2768
2769                 tmp = lseek(fd, 0, SEEK_CUR);
2770                 evsel = perf_evsel__new(&f_attr.attr, i);
2771
2772                 if (evsel == NULL)
2773                         goto out_delete_evlist;
2774
2775                 evsel->needs_swap = header->needs_swap;
2776                 /*
2777                  * Do it before so that if perf_evsel__alloc_id fails, this
2778                  * entry gets purged too at perf_evlist__delete().
2779                  */
2780                 perf_evlist__add(session->evlist, evsel);
2781
2782                 nr_ids = f_attr.ids.size / sizeof(u64);
2783                 /*
2784                  * We don't have the cpu and thread maps on the header, so
2785                  * for allocating the perf_sample_id table we fake 1 cpu and
2786                  * hattr->ids threads.
2787                  */
2788                 if (perf_evsel__alloc_id(evsel, 1, nr_ids))
2789                         goto out_delete_evlist;
2790
2791                 lseek(fd, f_attr.ids.offset, SEEK_SET);
2792
2793                 for (j = 0; j < nr_ids; j++) {
2794                         if (perf_header__getbuffer64(header, fd, &f_id, sizeof(f_id)))
2795                                 goto out_errno;
2796
2797                         perf_evlist__id_add(session->evlist, evsel, 0, j, f_id);
2798                 }
2799
2800                 lseek(fd, tmp, SEEK_SET);
2801         }
2802
2803         symbol_conf.nr_events = nr_attrs;
2804
2805         perf_header__process_sections(header, fd, &session->pevent,
2806                                       perf_file_section__process);
2807
2808         if (perf_evlist__prepare_tracepoint_events(session->evlist,
2809                                                    session->pevent))
2810                 goto out_delete_evlist;
2811
2812         return 0;
2813 out_errno:
2814         return -errno;
2815
2816 out_delete_evlist:
2817         perf_evlist__delete(session->evlist);
2818         session->evlist = NULL;
2819         return -ENOMEM;
2820 }
2821
2822 int perf_event__synthesize_attr(struct perf_tool *tool,
2823                                 struct perf_event_attr *attr, u32 ids, u64 *id,
2824                                 perf_event__handler_t process)
2825 {
2826         union perf_event *ev;
2827         size_t size;
2828         int err;
2829
2830         size = sizeof(struct perf_event_attr);
2831         size = PERF_ALIGN(size, sizeof(u64));
2832         size += sizeof(struct perf_event_header);
2833         size += ids * sizeof(u64);
2834
2835         ev = malloc(size);
2836
2837         if (ev == NULL)
2838                 return -ENOMEM;
2839
2840         ev->attr.attr = *attr;
2841         memcpy(ev->attr.id, id, ids * sizeof(u64));
2842
2843         ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
2844         ev->attr.header.size = (u16)size;
2845
2846         if (ev->attr.header.size == size)
2847                 err = process(tool, ev, NULL, NULL);
2848         else
2849                 err = -E2BIG;
2850
2851         free(ev);
2852
2853         return err;
2854 }
2855
2856 int perf_event__synthesize_attrs(struct perf_tool *tool,
2857                                    struct perf_session *session,
2858                                    perf_event__handler_t process)
2859 {
2860         struct perf_evsel *evsel;
2861         int err = 0;
2862
2863         list_for_each_entry(evsel, &session->evlist->entries, node) {
2864                 err = perf_event__synthesize_attr(tool, &evsel->attr, evsel->ids,
2865                                                   evsel->id, process);
2866                 if (err) {
2867                         pr_debug("failed to create perf header attribute\n");
2868                         return err;
2869                 }
2870         }
2871
2872         return err;
2873 }
2874
2875 int perf_event__process_attr(struct perf_tool *tool __maybe_unused,
2876                              union perf_event *event,
2877                              struct perf_evlist **pevlist)
2878 {
2879         u32 i, ids, n_ids;
2880         struct perf_evsel *evsel;
2881         struct perf_evlist *evlist = *pevlist;
2882
2883         if (evlist == NULL) {
2884                 *pevlist = evlist = perf_evlist__new();
2885                 if (evlist == NULL)
2886                         return -ENOMEM;
2887         }
2888
2889         evsel = perf_evsel__new(&event->attr.attr, evlist->nr_entries);
2890         if (evsel == NULL)
2891                 return -ENOMEM;
2892
2893         perf_evlist__add(evlist, evsel);
2894
2895         ids = event->header.size;
2896         ids -= (void *)&event->attr.id - (void *)event;
2897         n_ids = ids / sizeof(u64);
2898         /*
2899          * We don't have the cpu and thread maps on the header, so
2900          * for allocating the perf_sample_id table we fake 1 cpu and
2901          * hattr->ids threads.
2902          */
2903         if (perf_evsel__alloc_id(evsel, 1, n_ids))
2904                 return -ENOMEM;
2905
2906         for (i = 0; i < n_ids; i++) {
2907                 perf_evlist__id_add(evlist, evsel, 0, i, event->attr.id[i]);
2908         }
2909
2910         symbol_conf.nr_events = evlist->nr_entries;
2911
2912         return 0;
2913 }
2914
2915 int perf_event__synthesize_tracing_data(struct perf_tool *tool, int fd,
2916                                         struct perf_evlist *evlist,
2917                                         perf_event__handler_t process)
2918 {
2919         union perf_event ev;
2920         struct tracing_data *tdata;
2921         ssize_t size = 0, aligned_size = 0, padding;
2922         int err __maybe_unused = 0;
2923
2924         /*
2925          * We are going to store the size of the data followed
2926          * by the data contents. Since the fd descriptor is a pipe,
2927          * we cannot seek back to store the size of the data once
2928          * we know it. Instead we:
2929          *
2930          * - write the tracing data to the temp file
2931          * - get/write the data size to pipe
2932          * - write the tracing data from the temp file
2933          *   to the pipe
2934          */
2935         tdata = tracing_data_get(&evlist->entries, fd, true);
2936         if (!tdata)
2937                 return -1;
2938
2939         memset(&ev, 0, sizeof(ev));
2940
2941         ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
2942         size = tdata->size;
2943         aligned_size = PERF_ALIGN(size, sizeof(u64));
2944         padding = aligned_size - size;
2945         ev.tracing_data.header.size = sizeof(ev.tracing_data);
2946         ev.tracing_data.size = aligned_size;
2947
2948         process(tool, &ev, NULL, NULL);
2949
2950         /*
2951          * The put function will copy all the tracing data
2952          * stored in temp file to the pipe.
2953          */
2954         tracing_data_put(tdata);
2955
2956         write_padded(fd, NULL, 0, padding);
2957
2958         return aligned_size;
2959 }
2960
2961 int perf_event__process_tracing_data(struct perf_tool *tool __maybe_unused,
2962                                      union perf_event *event,
2963                                      struct perf_session *session)
2964 {
2965         ssize_t size_read, padding, size = event->tracing_data.size;
2966         off_t offset = lseek(session->fd, 0, SEEK_CUR);
2967         char buf[BUFSIZ];
2968
2969         /* setup for reading amidst mmap */
2970         lseek(session->fd, offset + sizeof(struct tracing_data_event),
2971               SEEK_SET);
2972
2973         size_read = trace_report(session->fd, &session->pevent,
2974                                  session->repipe);
2975         padding = PERF_ALIGN(size_read, sizeof(u64)) - size_read;
2976
2977         if (readn(session->fd, buf, padding) < 0) {
2978                 pr_err("%s: reading input file", __func__);
2979                 return -1;
2980         }
2981         if (session->repipe) {
2982                 int retw = write(STDOUT_FILENO, buf, padding);
2983                 if (retw <= 0 || retw != padding) {
2984                         pr_err("%s: repiping tracing data padding", __func__);
2985                         return -1;
2986                 }
2987         }
2988
2989         if (size_read + padding != size) {
2990                 pr_err("%s: tracing data size mismatch", __func__);
2991                 return -1;
2992         }
2993
2994         perf_evlist__prepare_tracepoint_events(session->evlist,
2995                                                session->pevent);
2996
2997         return size_read + padding;
2998 }
2999
3000 int perf_event__synthesize_build_id(struct perf_tool *tool,
3001                                     struct dso *pos, u16 misc,
3002                                     perf_event__handler_t process,
3003                                     struct machine *machine)
3004 {
3005         union perf_event ev;
3006         size_t len;
3007         int err = 0;
3008
3009         if (!pos->hit)
3010                 return err;
3011
3012         memset(&ev, 0, sizeof(ev));
3013
3014         len = pos->long_name_len + 1;
3015         len = PERF_ALIGN(len, NAME_ALIGN);
3016         memcpy(&ev.build_id.build_id, pos->build_id, sizeof(pos->build_id));
3017         ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
3018         ev.build_id.header.misc = misc;
3019         ev.build_id.pid = machine->pid;
3020         ev.build_id.header.size = sizeof(ev.build_id) + len;
3021         memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
3022
3023         err = process(tool, &ev, NULL, machine);
3024
3025         return err;
3026 }
3027
3028 int perf_event__process_build_id(struct perf_tool *tool __maybe_unused,
3029                                  union perf_event *event,
3030                                  struct perf_session *session)
3031 {
3032         __event_process_build_id(&event->build_id,
3033                                  event->build_id.filename,
3034                                  session);
3035         return 0;
3036 }
3037
3038 void disable_buildid_cache(void)
3039 {
3040         no_buildid_cache = true;
3041 }