tools/perf/builtin-record.c

   1 /*
   2  * builtin-record.c
   3  *
   4  * Builtin record command: Record the profile of a workload
   5  * (or a CPU, or a PID) into the perf.data output file - for
   6  * later analysis via perf report.
   7  */
   8 #include "builtin.h"
   9
  10 #include "perf.h"
  11
  12 #include "util/build-id.h"
  13 #include "util/util.h"
  14 #include "util/parse-options.h"
  15 #include "util/parse-events.h"
  16
  17 #include "util/header.h"
  18 #include "util/event.h"
  19 #include "util/evlist.h"
  20 #include "util/evsel.h"
  21 #include "util/debug.h"
  22 #include "util/session.h"
  23 #include "util/tool.h"
  24 #include "util/symbol.h"
  25 #include "util/cpumap.h"
  26 #include "util/thread_map.h"
  27
  28 #include <unistd.h>
  29 #include <sched.h>
  30 #include <sys/mman.h>
  31
  32 #ifndef HAVE_ON_EXIT
  33 #ifndef ATEXIT_MAX
  34 #define ATEXIT_MAX 32
  35 #endif
  36 static int __on_exit_count = 0;
  37 typedef void (*on_exit_func_t) (int, void *);
  38 static on_exit_func_t __on_exit_funcs[ATEXIT_MAX];
  39 static void *__on_exit_args[ATEXIT_MAX];
  40 static int __exitcode = 0;
  41 static void __handle_on_exit_funcs(void);
  42 static int on_exit(on_exit_func_t function, void *arg);
  43 #define exit(x) (exit)(__exitcode = (x))
  44
  45 static int on_exit(on_exit_func_t function, void *arg)
  46 {
  47         if (__on_exit_count == ATEXIT_MAX)
  48                 return -ENOMEM;
  49         else if (__on_exit_count == 0)
  50                 atexit(__handle_on_exit_funcs);
  51         __on_exit_funcs[__on_exit_count] = function;
  52         __on_exit_args[__on_exit_count++] = arg;
  53         return 0;
  54 }
  55
  56 static void __handle_on_exit_funcs(void)
  57 {
  58         int i;
  59         for (i = 0; i < __on_exit_count; i++)
  60                 __on_exit_funcs[i] (__exitcode, __on_exit_args[i]);
  61 }
  62 #endif
  63
  64 struct perf_record {
  65         struct perf_tool        tool;
  66         struct perf_record_opts opts;
  67         u64                     bytes_written;
  68         const char              *output_name;
  69         struct perf_evlist      *evlist;
  70         struct perf_session     *session;
  71         const char              *progname;
  72         int                     output;
  73         unsigned int            page_size;
  74         int                     realtime_prio;
  75         bool                    no_buildid;
  76         bool                    no_buildid_cache;
  77         long                    samples;
  78         off_t                   post_processing_offset;
  79 };
  80
  81 static void advance_output(struct perf_record *rec, size_t size)
  82 {
  83         rec->bytes_written += size;
  84 }
  85
  86 static int write_output(struct perf_record *rec, void *buf, size_t size)
  87 {
  88         while (size) {
  89                 int ret = write(rec->output, buf, size);
  90
  91                 if (ret < 0) {
  92                         pr_err("failed to write\n");
  93                         return -1;
  94                 }
  95
  96                 size -= ret;
  97                 buf += ret;
  98
  99                 rec->bytes_written += ret;
 100         }
 101
 102         return 0;
 103 }
 104
 105 static int process_synthesized_event(struct perf_tool *tool,
 106                                      union perf_event *event,
 107                                      struct perf_sample *sample __maybe_unused,
 108                                      struct machine *machine __maybe_unused)
 109 {
 110         struct perf_record *rec = container_of(tool, struct perf_record, tool);
 111         if (write_output(rec, event, event->header.size) < 0)
 112                 return -1;
 113
 114         return 0;
 115 }
 116
 117 static int perf_record__mmap_read(struct perf_record *rec,
 118                                    struct perf_mmap *md)
 119 {
 120         unsigned int head = perf_mmap__read_head(md);
 121         unsigned int old = md->prev;
 122         unsigned char *data = md->base + rec->page_size;
 123         unsigned long size;
 124         void *buf;
 125         int rc = 0;
 126
 127         if (old == head)
 128                 return 0;
 129
 130         rec->samples++;
 131
 132         size = head - old;
 133
 134         if ((old & md->mask) + size != (head & md->mask)) {
 135                 buf = &data[old & md->mask];
 136                 size = md->mask + 1 - (old & md->mask);
 137                 old += size;
 138
 139                 if (write_output(rec, buf, size) < 0) {
 140                         rc = -1;
 141                         goto out;
 142                 }
 143         }
 144
 145         buf = &data[old & md->mask];
 146         size = head - old;
 147         old += size;
 148
 149         if (write_output(rec, buf, size) < 0) {
 150                 rc = -1;
 151                 goto out;
 152         }
 153
 154         md->prev = old;
 155         perf_mmap__write_tail(md, old);
 156
 157 out:
 158         return rc;
 159 }
 160
 161 static volatile int done = 0;
 162 static volatile int signr = -1;
 163 static volatile int child_finished = 0;
 164
 165 static void sig_handler(int sig)
 166 {
 167         if (sig == SIGCHLD)
 168                 child_finished = 1;
 169
 170         done = 1;
 171         signr = sig;
 172 }
 173
 174 static void perf_record__sig_exit(int exit_status __maybe_unused, void *arg)
 175 {
 176         struct perf_record *rec = arg;
 177         int status;
 178
 179         if (rec->evlist->workload.pid > 0) {
 180                 if (!child_finished)
 181                         kill(rec->evlist->workload.pid, SIGTERM);
 182
 183                 wait(&status);
 184                 if (WIFSIGNALED(status))
 185                         psignal(WTERMSIG(status), rec->progname);
 186         }
 187
 188         if (signr == -1 || signr == SIGUSR1)
 189                 return;
 190
 191         signal(signr, SIG_DFL);
 192 }
 193
 194 static int perf_record__open(struct perf_record *rec)
 195 {
 196         char msg[512];
 197         struct perf_evsel *pos;
 198         struct perf_evlist *evlist = rec->evlist;
 199         struct perf_session *session = rec->session;
 200         struct perf_record_opts *opts = &rec->opts;
 201         int rc = 0;
 202
 203         perf_evlist__config(evlist, opts);
 204
 205         list_for_each_entry(pos, &evlist->entries, node) {
 206 try_again:
 207                 if (perf_evsel__open(pos, evlist->cpus, evlist->threads) < 0) {
 208                         if (perf_evsel__fallback(pos, errno, msg, sizeof(msg))) {
 209                                 if (verbose)
 210                                         ui__warning("%s\n", msg);
 211                                 goto try_again;
 212                         }
 213
 214                         rc = -errno;
 215                         perf_evsel__open_strerror(pos, &opts->target,
 216                                                   errno, msg, sizeof(msg));
 217                         ui__error("%s\n", msg);
 218                         goto out;
 219                 }
 220         }
 221
 222         if (perf_evlist__apply_filters(evlist)) {
 223                 error("failed to set filter with %d (%s)\n", errno,
 224                         strerror(errno));
 225                 rc = -1;
 226                 goto out;
 227         }
 228
 229         if (perf_evlist__mmap(evlist, opts->mmap_pages, false) < 0) {
 230                 if (errno == EPERM) {
 231                         pr_err("Permission error mapping pages.\n"
 232                                "Consider increasing "
 233                                "/proc/sys/kernel/perf_event_mlock_kb,\n"
 234                                "or try again with a smaller value of -m/--mmap_pages.\n"
 235                                "(current value: %d)\n", opts->mmap_pages);
 236                         rc = -errno;
 237                 } else if (!is_power_of_2(opts->mmap_pages) &&
 238                            (opts->mmap_pages != UINT_MAX)) {
 239                         pr_err("--mmap_pages/-m value must be a power of two.");
 240                         rc = -EINVAL;
 241                 } else {
 242                         pr_err("failed to mmap with %d (%s)\n", errno, strerror(errno));
 243                         rc = -errno;
 244                 }
 245                 goto out;
 246         }
 247
 248         session->evlist = evlist;
 249         perf_session__set_id_hdr_size(session);
 250 out:
 251         return rc;
 252 }
 253
 254 static int process_buildids(struct perf_record *rec)
 255 {
 256         u64 size = lseek(rec->output, 0, SEEK_CUR);
 257
 258         if (size == 0)
 259                 return 0;
 260
 261         rec->session->fd = rec->output;
 262         return __perf_session__process_events(rec->session, rec->post_processing_offset,
 263                                               size - rec->post_processing_offset,
 264                                               size, &build_id__mark_dso_hit_ops);
 265 }
 266
 267 static void perf_record__exit(int status, void *arg)
 268 {
 269         struct perf_record *rec = arg;
 270
 271         if (status != 0)
 272                 return;
 273
 274         if (!rec->opts.pipe_output) {
 275                 rec->session->header.data_size += rec->bytes_written;
 276
 277                 if (!rec->no_buildid)
 278                         process_buildids(rec);
 279                 perf_session__write_header(rec->session, rec->evlist,
 280                                            rec->output, true);
 281                 perf_session__delete(rec->session);
 282                 perf_evlist__delete(rec->evlist);
 283                 symbol__exit();
 284         }
 285 }
 286
 287 static void perf_event__synthesize_guest_os(struct machine *machine, void *data)
 288 {
 289         int err;
 290         struct perf_tool *tool = data;
 291         /*
 292          *As for guest kernel when processing subcommand record&report,
 293          *we arrange module mmap prior to guest kernel mmap and trigger
 294          *a preload dso because default guest module symbols are loaded
 295          *from guest kallsyms instead of /lib/modules/XXX/XXX. This
 296          *method is used to avoid symbol missing when the first addr is
 297          *in module instead of in guest kernel.
 298          */
 299         err = perf_event__synthesize_modules(tool, process_synthesized_event,
 300                                              machine);
 301         if (err < 0)
 302                 pr_err("Couldn't record guest kernel [%d]'s reference"
 303                        " relocation symbol.\n", machine->pid);
 304
 305         /*
 306          * We use _stext for guest kernel because guest kernel's /proc/kallsyms
 307          * have no _text sometimes.
 308          */
 309         err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 310                                                  machine, "_text");
 311         if (err < 0)
 312                 err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 313                                                          machine, "_stext");
 314         if (err < 0)
 315                 pr_err("Couldn't record guest kernel [%d]'s reference"
 316                        " relocation symbol.\n", machine->pid);
 317 }
 318
 319 static struct perf_event_header finished_round_event = {
 320         .size = sizeof(struct perf_event_header),
 321         .type = PERF_RECORD_FINISHED_ROUND,
 322 };
 323
 324 static int perf_record__mmap_read_all(struct perf_record *rec)
 325 {
 326         int i;
 327         int rc = 0;
 328
 329         for (i = 0; i < rec->evlist->nr_mmaps; i++) {
 330                 if (rec->evlist->mmap[i].base) {
 331                         if (perf_record__mmap_read(rec, &rec->evlist->mmap[i]) != 0) {
 332                                 rc = -1;
 333                                 goto out;
 334                         }
 335                 }
 336         }
 337
 338         if (perf_header__has_feat(&rec->session->header, HEADER_TRACING_DATA))
 339                 rc = write_output(rec, &finished_round_event,
 340                                   sizeof(finished_round_event));
 341
 342 out:
 343         return rc;
 344 }
 345
 346 static int __cmd_record(struct perf_record *rec, int argc, const char **argv)
 347 {
 348         struct stat st;
 349         int flags;
 350         int err, output, feat;
 351         unsigned long waking = 0;
 352         const bool forks = argc > 0;
 353         struct machine *machine;
 354         struct perf_tool *tool = &rec->tool;
 355         struct perf_record_opts *opts = &rec->opts;
 356         struct perf_evlist *evsel_list = rec->evlist;
 357         const char *output_name = rec->output_name;
 358         struct perf_session *session;
 359         bool disabled = false;
 360
 361         rec->progname = argv[0];
 362
 363         rec->page_size = sysconf(_SC_PAGE_SIZE);
 364
 365         on_exit(perf_record__sig_exit, rec);
 366         signal(SIGCHLD, sig_handler);
 367         signal(SIGINT, sig_handler);
 368         signal(SIGUSR1, sig_handler);
 369         signal(SIGTERM, sig_handler);
 370
 371         if (!output_name) {
 372                 if (!fstat(STDOUT_FILENO, &st) && S_ISFIFO(st.st_mode))
 373                         opts->pipe_output = true;
 374                 else
 375                         rec->output_name = output_name = "perf.data";
 376         }
 377         if (output_name) {
 378                 if (!strcmp(output_name, "-"))
 379                         opts->pipe_output = true;
 380                 else if (!stat(output_name, &st) && st.st_size) {
 381                         char oldname[PATH_MAX];
 382                         snprintf(oldname, sizeof(oldname), "%s.old",
 383                                  output_name);
 384                         unlink(oldname);
 385                         rename(output_name, oldname);
 386                 }
 387         }
 388
 389         flags = O_CREAT|O_RDWR|O_TRUNC;
 390
 391         if (opts->pipe_output)
 392                 output = STDOUT_FILENO;
 393         else
 394                 output = open(output_name, flags, S_IRUSR | S_IWUSR);
 395         if (output < 0) {
 396                 perror("failed to create output file");
 397                 return -1;
 398         }
 399
 400         rec->output = output;
 401
 402         session = perf_session__new(output_name, O_WRONLY,
 403                                     true, false, NULL);
 404         if (session == NULL) {
 405                 pr_err("Not enough memory for reading perf file header\n");
 406                 return -1;
 407         }
 408
 409         rec->session = session;
 410
 411         for (feat = HEADER_FIRST_FEATURE; feat < HEADER_LAST_FEATURE; feat++)
 412                 perf_header__set_feat(&session->header, feat);
 413
 414         if (rec->no_buildid)
 415                 perf_header__clear_feat(&session->header, HEADER_BUILD_ID);
 416
 417         if (!have_tracepoints(&evsel_list->entries))
 418                 perf_header__clear_feat(&session->header, HEADER_TRACING_DATA);
 419
 420         if (!rec->opts.branch_stack)
 421                 perf_header__clear_feat(&session->header, HEADER_BRANCH_STACK);
 422
 423         if (forks) {
 424                 err = perf_evlist__prepare_workload(evsel_list, &opts->target,
 425                                                     argv, opts->pipe_output,
 426                                                     true);
 427                 if (err < 0) {
 428                         pr_err("Couldn't run the workload!\n");
 429                         goto out_delete_session;
 430                 }
 431         }
 432
 433         if (perf_record__open(rec) != 0) {
 434                 err = -1;
 435                 goto out_delete_session;
 436         }
 437
 438         if (!evsel_list->nr_groups)
 439                 perf_header__clear_feat(&session->header, HEADER_GROUP_DESC);
 440
 441         /*
 442          * perf_session__delete(session) will be called at perf_record__exit()
 443          */
 444         on_exit(perf_record__exit, rec);
 445
 446         if (opts->pipe_output) {
 447                 err = perf_header__write_pipe(output);
 448                 if (err < 0)
 449                         goto out_delete_session;
 450         } else {
 451                 err = perf_session__write_header(session, evsel_list,
 452                                                  output, false);
 453                 if (err < 0)
 454                         goto out_delete_session;
 455         }
 456
 457         if (!rec->no_buildid
 458             && !perf_header__has_feat(&session->header, HEADER_BUILD_ID)) {
 459                 pr_err("Couldn't generate buildids. "
 460                        "Use --no-buildid to profile anyway.\n");
 461                 err = -1;
 462                 goto out_delete_session;
 463         }
 464
 465         rec->post_processing_offset = lseek(output, 0, SEEK_CUR);
 466
 467         machine = &session->machines.host;
 468
 469         if (opts->pipe_output) {
 470                 err = perf_event__synthesize_attrs(tool, session,
 471                                                    process_synthesized_event);
 472                 if (err < 0) {
 473                         pr_err("Couldn't synthesize attrs.\n");
 474                         goto out_delete_session;
 475                 }
 476
 477                 if (have_tracepoints(&evsel_list->entries)) {
 478                         /*
 479                          * FIXME err <= 0 here actually means that
 480                          * there were no tracepoints so its not really
 481                          * an error, just that we don't need to
 482                          * synthesize anything.  We really have to
 483                          * return this more properly and also
 484                          * propagate errors that now are calling die()
 485                          */
 486                         err = perf_event__synthesize_tracing_data(tool, output, evsel_list,
 487                                                                   process_synthesized_event);
 488                         if (err <= 0) {
 489                                 pr_err("Couldn't record tracing data.\n");
 490                                 goto out_delete_session;
 491                         }
 492                         advance_output(rec, err);
 493                 }
 494         }
 495
 496         err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 497                                                  machine, "_text");
 498         if (err < 0)
 499                 err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 500                                                          machine, "_stext");
 501         if (err < 0)
 502                 pr_err("Couldn't record kernel reference relocation symbol\n"
 503                        "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
 504                        "Check /proc/kallsyms permission or run as root.\n");
 505
 506         err = perf_event__synthesize_modules(tool, process_synthesized_event,
 507                                              machine);
 508         if (err < 0)
 509                 pr_err("Couldn't record kernel module information.\n"
 510                        "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
 511                        "Check /proc/modules permission or run as root.\n");
 512
 513         if (perf_guest) {
 514                 machines__process_guests(&session->machines,
 515                                          perf_event__synthesize_guest_os, tool);
 516         }
 517
 518         if (perf_target__has_task(&opts->target))
 519                 err = perf_event__synthesize_thread_map(tool, evsel_list->threads,
 520                                                   process_synthesized_event,
 521                                                   machine);
 522         else if (perf_target__has_cpu(&opts->target))
 523                 err = perf_event__synthesize_threads(tool, process_synthesized_event,
 524                                                machine);
 525         else /* command specified */
 526                 err = 0;
 527
 528         if (err != 0)
 529                 goto out_delete_session;
 530
 531         if (rec->realtime_prio) {
 532                 struct sched_param param;
 533
 534                 param.sched_priority = rec->realtime_prio;
 535                 if (sched_setscheduler(0, SCHED_FIFO, &param)) {
 536                         pr_err("Could not set realtime priority.\n");
 537                         err = -1;
 538                         goto out_delete_session;
 539                 }
 540         }
 541
 542         /*
 543          * When perf is starting the traced process, all the events
 544          * (apart from group members) have enable_on_exec=1 set,
 545          * so don't spoil it by prematurely enabling them.
 546          */
 547         if (!perf_target__none(&opts->target))
 548                 perf_evlist__enable(evsel_list);
 549
 550         /*
 551          * Let the child rip
 552          */
 553         if (forks)
 554                 perf_evlist__start_workload(evsel_list);
 555
 556         for (;;) {
 557                 int hits = rec->samples;
 558
 559                 if (perf_record__mmap_read_all(rec) < 0) {
 560                         err = -1;
 561                         goto out_delete_session;
 562                 }
 563
 564                 if (hits == rec->samples) {
 565                         if (done)
 566                                 break;
 567                         err = poll(evsel_list->pollfd, evsel_list->nr_fds, -1);
 568                         waking++;
 569                 }
 570
 571                 /*
 572                  * When perf is starting the traced process, at the end events
 573                  * die with the process and we wait for that. Thus no need to
 574                  * disable events in this case.
 575                  */
 576                 if (done && !disabled && !perf_target__none(&opts->target)) {
 577                         perf_evlist__disable(evsel_list);
 578                         disabled = true;
 579                 }
 580         }
 581
 582         if (quiet || signr == SIGUSR1)
 583                 return 0;
 584
 585         fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
 586
 587         /*
 588          * Approximate RIP event size: 24 bytes.
 589          */
 590         fprintf(stderr,
 591                 "[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64 " samples) ]\n",
 592                 (double)rec->bytes_written / 1024.0 / 1024.0,
 593                 output_name,
 594                 rec->bytes_written / 24);
 595
 596         return 0;
 597
 598 out_delete_session:
 599         perf_session__delete(session);
 600         return err;
 601 }
 602
 603 #define BRANCH_OPT(n, m) \
 604         { .name = n, .mode = (m) }
 605
 606 #define BRANCH_END { .name = NULL }
 607
 608 struct branch_mode {
 609         const char *name;
 610         int mode;
 611 };
 612
 613 static const struct branch_mode branch_modes[] = {
 614         BRANCH_OPT("u", PERF_SAMPLE_BRANCH_USER),
 615         BRANCH_OPT("k", PERF_SAMPLE_BRANCH_KERNEL),
 616         BRANCH_OPT("hv", PERF_SAMPLE_BRANCH_HV),
 617         BRANCH_OPT("any", PERF_SAMPLE_BRANCH_ANY),
 618         BRANCH_OPT("any_call", PERF_SAMPLE_BRANCH_ANY_CALL),
 619         BRANCH_OPT("any_ret", PERF_SAMPLE_BRANCH_ANY_RETURN),
 620         BRANCH_OPT("ind_call", PERF_SAMPLE_BRANCH_IND_CALL),
 621         BRANCH_END
 622 };
 623
 624 static int
 625 parse_branch_stack(const struct option *opt, const char *str, int unset)
 626 {
 627 #define ONLY_PLM \
 628         (PERF_SAMPLE_BRANCH_USER        |\
 629          PERF_SAMPLE_BRANCH_KERNEL      |\
 630          PERF_SAMPLE_BRANCH_HV)
 631
 632         uint64_t *mode = (uint64_t *)opt->value;
 633         const struct branch_mode *br;
 634         char *s, *os = NULL, *p;
 635         int ret = -1;
 636
 637         if (unset)
 638                 return 0;
 639
 640         /*
 641          * cannot set it twice, -b + --branch-filter for instance
 642          */
 643         if (*mode)
 644                 return -1;
 645
 646         /* str may be NULL in case no arg is passed to -b */
 647         if (str) {
 648                 /* because str is read-only */
 649                 s = os = strdup(str);
 650                 if (!s)
 651                         return -1;
 652
 653                 for (;;) {
 654                         p = strchr(s, ',');
 655                         if (p)
 656                                 *p = '\0';
 657
 658                         for (br = branch_modes; br->name; br++) {
 659                                 if (!strcasecmp(s, br->name))
 660                                         break;
 661                         }
 662                         if (!br->name) {
 663                                 ui__warning("unknown branch filter %s,"
 664                                             " check man page\n", s);
 665                                 goto error;
 666                         }
 667
 668                         *mode |= br->mode;
 669
 670                         if (!p)
 671                                 break;
 672
 673                         s = p + 1;
 674                 }
 675         }
 676         ret = 0;
 677
 678         /* default to any branch */
 679         if ((*mode & ~ONLY_PLM) == 0) {
 680                 *mode = PERF_SAMPLE_BRANCH_ANY;
 681         }
 682 error:
 683         free(os);
 684         return ret;
 685 }
 686
 687 #ifdef LIBUNWIND_SUPPORT
 688 static int get_stack_size(char *str, unsigned long *_size)
 689 {
 690         char *endptr;
 691         unsigned long size;
 692         unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
 693
 694         size = strtoul(str, &endptr, 0);
 695
 696         do {
 697                 if (*endptr)
 698                         break;
 699
 700                 size = round_up(size, sizeof(u64));
 701                 if (!size || size > max_size)
 702                         break;
 703
 704                 *_size = size;
 705                 return 0;
 706
 707         } while (0);
 708
 709         pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
 710                max_size, str);
 711         return -1;
 712 }
 713 #endif /* LIBUNWIND_SUPPORT */
 714
 715 int record_parse_callchain_opt(const struct option *opt,
 716                                const char *arg, int unset)
 717 {
 718         struct perf_record_opts *opts = opt->value;
 719         char *tok, *name, *saveptr = NULL;
 720         char *buf;
 721         int ret = -1;
 722
 723         /* --no-call-graph */
 724         if (unset)
 725                 return 0;
 726
 727         /* We specified default option if none is provided. */
 728         BUG_ON(!arg);
 729
 730         /* We need buffer that we know we can write to. */
 731         buf = malloc(strlen(arg) + 1);
 732         if (!buf)
 733                 return -ENOMEM;
 734
 735         strcpy(buf, arg);
 736
 737         tok = strtok_r((char *)buf, ",", &saveptr);
 738         name = tok ? : (char *)buf;
 739
 740         do {
 741                 /* Framepointer style */
 742                 if (!strncmp(name, "fp", sizeof("fp"))) {
 743                         if (!strtok_r(NULL, ",", &saveptr)) {
 744                                 opts->call_graph = CALLCHAIN_FP;
 745                                 ret = 0;
 746                         } else
 747                                 pr_err("callchain: No more arguments "
 748                                        "needed for -g fp\n");
 749                         break;
 750
 751 #ifdef LIBUNWIND_SUPPORT
 752                 /* Dwarf style */
 753                 } else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
 754                         const unsigned long default_stack_dump_size = 8192;
 755
 756                         ret = 0;
 757                         opts->call_graph = CALLCHAIN_DWARF;
 758                         opts->stack_dump_size = default_stack_dump_size;
 759
 760                         tok = strtok_r(NULL, ",", &saveptr);
 761                         if (tok) {
 762                                 unsigned long size = 0;
 763
 764                                 ret = get_stack_size(tok, &size);
 765                                 opts->stack_dump_size = size;
 766                         }
 767
 768                         if (!ret)
 769                                 pr_debug("callchain: stack dump size %d\n",
 770                                          opts->stack_dump_size);
 771 #endif /* LIBUNWIND_SUPPORT */
 772                 } else {
 773                         pr_err("callchain: Unknown -g option "
 774                                "value: %s\n", arg);
 775                         break;
 776                 }
 777
 778         } while (0);
 779
 780         free(buf);
 781
 782         if (!ret)
 783                 pr_debug("callchain: type %d\n", opts->call_graph);
 784
 785         return ret;
 786 }
 787
 788 static const char * const record_usage[] = {
 789         "perf record [<options>] [<command>]",
 790         "perf record [<options>] -- <command> [<options>]",
 791         NULL
 792 };
 793
 794 /*
 795  * XXX Ideally would be local to cmd_record() and passed to a perf_record__new
 796  * because we need to have access to it in perf_record__exit, that is called
 797  * after cmd_record() exits, but since record_options need to be accessible to
 798  * builtin-script, leave it here.
 799  *
 800  * At least we don't ouch it in all the other functions here directly.
 801  *
 802  * Just say no to tons of global variables, sigh.
 803  */
 804 static struct perf_record record = {
 805         .opts = {
 806                 .mmap_pages          = UINT_MAX,
 807                 .user_freq           = UINT_MAX,
 808                 .user_interval       = ULLONG_MAX,
 809                 .freq                = 4000,
 810                 .target              = {
 811                         .uses_mmap   = true,
 812                 },
 813         },
 814 };
 815
 816 #define CALLCHAIN_HELP "do call-graph (stack chain/backtrace) recording: "
 817
 818 #ifdef LIBUNWIND_SUPPORT
 819 const char record_callchain_help[] = CALLCHAIN_HELP "[fp] dwarf";
 820 #else
 821 const char record_callchain_help[] = CALLCHAIN_HELP "[fp]";
 822 #endif
 823
 824 /*
 825  * XXX Will stay a global variable till we fix builtin-script.c to stop messing
 826  * with it and switch to use the library functions in perf_evlist that came
 827  * from builtin-record.c, i.e. use perf_record_opts,
 828  * perf_evlist__prepare_workload, etc instead of fork+exec'in 'perf record',
 829  * using pipes, etc.
 830  */
 831 const struct option record_options[] = {
 832         OPT_CALLBACK('e', "event", &record.evlist, "event",
 833                      "event selector. use 'perf list' to list available events",
 834                      parse_events_option),
 835         OPT_CALLBACK(0, "filter", &record.evlist, "filter",
 836                      "event filter", parse_filter),
 837         OPT_STRING('p', "pid", &record.opts.target.pid, "pid",
 838                     "record events on existing process id"),
 839         OPT_STRING('t', "tid", &record.opts.target.tid, "tid",
 840                     "record events on existing thread id"),
 841         OPT_INTEGER('r', "realtime", &record.realtime_prio,
 842                     "collect data with this RT SCHED_FIFO priority"),
 843         OPT_BOOLEAN('D', "no-delay", &record.opts.no_delay,
 844                     "collect data without buffering"),
 845         OPT_BOOLEAN('R', "raw-samples", &record.opts.raw_samples,
 846                     "collect raw sample records from all opened counters"),
 847         OPT_BOOLEAN('a', "all-cpus", &record.opts.target.system_wide,
 848                             "system-wide collection from all CPUs"),
 849         OPT_STRING('C', "cpu", &record.opts.target.cpu_list, "cpu",
 850                     "list of cpus to monitor"),
 851         OPT_U64('c', "count", &record.opts.user_interval, "event period to sample"),
 852         OPT_STRING('o', "output", &record.output_name, "file",
 853                     "output file name"),
 854         OPT_BOOLEAN('i', "no-inherit", &record.opts.no_inherit,
 855                     "child tasks do not inherit counters"),
 856         OPT_UINTEGER('F', "freq", &record.opts.user_freq, "profile at this frequency"),
 857         OPT_UINTEGER('m', "mmap-pages", &record.opts.mmap_pages,
 858                      "number of mmap data pages"),
 859         OPT_BOOLEAN(0, "group", &record.opts.group,
 860                     "put the counters into a counter group"),
 861         OPT_CALLBACK_DEFAULT('g', "call-graph", &record.opts,
 862                              "mode[,dump_size]", record_callchain_help,
 863                              &record_parse_callchain_opt, "fp"),
 864         OPT_INCR('v', "verbose", &verbose,
 865                     "be more verbose (show counter open errors, etc)"),
 866         OPT_BOOLEAN('q', "quiet", &quiet, "don't print any message"),
 867         OPT_BOOLEAN('s', "stat", &record.opts.inherit_stat,
 868                     "per thread counts"),
 869         OPT_BOOLEAN('d', "data", &record.opts.sample_address,
 870                     "Sample addresses"),
 871         OPT_BOOLEAN('T', "timestamp", &record.opts.sample_time, "Sample timestamps"),
 872         OPT_BOOLEAN('P', "period", &record.opts.period, "Sample period"),
 873         OPT_BOOLEAN('n', "no-samples", &record.opts.no_samples,
 874                     "don't sample"),
 875         OPT_BOOLEAN('N', "no-buildid-cache", &record.no_buildid_cache,
 876                     "do not update the buildid cache"),
 877         OPT_BOOLEAN('B', "no-buildid", &record.no_buildid,
 878                     "do not collect buildids in perf.data"),
 879         OPT_CALLBACK('G', "cgroup", &record.evlist, "name",
 880                      "monitor event in cgroup name only",
 881                      parse_cgroups),
 882         OPT_STRING('u', "uid", &record.opts.target.uid_str, "user",
 883                    "user to profile"),
 884
 885         OPT_CALLBACK_NOOPT('b', "branch-any", &record.opts.branch_stack,
 886                      "branch any", "sample any taken branches",
 887                      parse_branch_stack),
 888
 889         OPT_CALLBACK('j', "branch-filter", &record.opts.branch_stack,
 890                      "branch filter mask", "branch stack filter modes",
 891                      parse_branch_stack),
 892         OPT_BOOLEAN('W', "weight", &record.opts.sample_weight,
 893                     "sample by weight (on special events only)"),
 894         OPT_END()
 895 };
 896
 897 int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
 898 {
 899         int err = -ENOMEM;
 900         struct perf_evlist *evsel_list;
 901         struct perf_record *rec = &record;
 902         char errbuf[BUFSIZ];
 903
 904         evsel_list = perf_evlist__new();
 905         if (evsel_list == NULL)
 906                 return -ENOMEM;
 907
 908         rec->evlist = evsel_list;
 909
 910         argc = parse_options(argc, argv, record_options, record_usage,
 911                             PARSE_OPT_STOP_AT_NON_OPTION);
 912         if (!argc && perf_target__none(&rec->opts.target))
 913                 usage_with_options(record_usage, record_options);
 914
 915         if (nr_cgroups && !rec->opts.target.system_wide) {
 916                 ui__error("cgroup monitoring only available in"
 917                           " system-wide mode\n");
 918                 usage_with_options(record_usage, record_options);
 919         }
 920
 921         symbol__init();
 922
 923         if (symbol_conf.kptr_restrict)
 924                 pr_warning(
 925 "WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,\n"
 926 "check /proc/sys/kernel/kptr_restrict.\n\n"
 927 "Samples in kernel functions may not be resolved if a suitable vmlinux\n"
 928 "file is not found in the buildid cache or in the vmlinux path.\n\n"
 929 "Samples in kernel modules won't be resolved at all.\n\n"
 930 "If some relocation was applied (e.g. kexec) symbols may be misresolved\n"
 931 "even with a suitable vmlinux or kallsyms file.\n\n");
 932
 933         if (rec->no_buildid_cache || rec->no_buildid)
 934                 disable_buildid_cache();
 935
 936         if (evsel_list->nr_entries == 0 &&
 937             perf_evlist__add_default(evsel_list) < 0) {
 938                 pr_err("Not enough memory for event selector list\n");
 939                 goto out_symbol_exit;
 940         }
 941
 942         err = perf_target__validate(&rec->opts.target);
 943         if (err) {
 944                 perf_target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
 945                 ui__warning("%s", errbuf);
 946         }
 947
 948         err = perf_target__parse_uid(&rec->opts.target);
 949         if (err) {
 950                 int saved_errno = errno;
 951
 952                 perf_target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
 953                 ui__error("%s", errbuf);
 954
 955                 err = -saved_errno;
 956                 goto out_symbol_exit;
 957         }
 958
 959         err = -ENOMEM;
 960         if (perf_evlist__create_maps(evsel_list, &rec->opts.target) < 0)
 961                 usage_with_options(record_usage, record_options);
 962
 963         if (rec->opts.user_interval != ULLONG_MAX)
 964                 rec->opts.default_interval = rec->opts.user_interval;
 965         if (rec->opts.user_freq != UINT_MAX)
 966                 rec->opts.freq = rec->opts.user_freq;
 967
 968         /*
 969          * User specified count overrides default frequency.
 970          */
 971         if (rec->opts.default_interval)
 972                 rec->opts.freq = 0;
 973         else if (rec->opts.freq) {
 974                 rec->opts.default_interval = rec->opts.freq;
 975         } else {
 976                 ui__error("frequency and count are zero, aborting\n");
 977                 err = -EINVAL;
 978                 goto out_free_fd;
 979         }
 980
 981         err = __cmd_record(&record, argc, argv);
 982
 983         perf_evlist__munmap(evsel_list);
 984         perf_evlist__close(evsel_list);
 985 out_free_fd:
 986         perf_evlist__delete_maps(evsel_list);
 987 out_symbol_exit:
 988         symbol__exit();
 989         return err;
 990 }