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 #define _FILE_OFFSET_BITS 64
   9
  10 #include "builtin.h"
  11
  12 #include "perf.h"
  13
  14 #include "util/build-id.h"
  15 #include "util/util.h"
  16 #include "util/parse-options.h"
  17 #include "util/parse-events.h"
  18
  19 #include "util/header.h"
  20 #include "util/event.h"
  21 #include "util/evlist.h"
  22 #include "util/evsel.h"
  23 #include "util/debug.h"
  24 #include "util/session.h"
  25 #include "util/tool.h"
  26 #include "util/symbol.h"
  27 #include "util/cpumap.h"
  28 #include "util/thread_map.h"
  29
  30 #include <unistd.h>
  31 #include <sched.h>
  32 #include <sys/mman.h>
  33
  34 #ifndef HAVE_ON_EXIT
  35 #ifndef ATEXIT_MAX
  36 #define ATEXIT_MAX 32
  37 #endif
  38 static int __on_exit_count = 0;
  39 typedef void (*on_exit_func_t) (int, void *);
  40 static on_exit_func_t __on_exit_funcs[ATEXIT_MAX];
  41 static void *__on_exit_args[ATEXIT_MAX];
  42 static int __exitcode = 0;
  43 static void __handle_on_exit_funcs(void);
  44 static int on_exit(on_exit_func_t function, void *arg);
  45 #define exit(x) (exit)(__exitcode = (x))
  46
  47 static int on_exit(on_exit_func_t function, void *arg)
  48 {
  49         if (__on_exit_count == ATEXIT_MAX)
  50                 return -ENOMEM;
  51         else if (__on_exit_count == 0)
  52                 atexit(__handle_on_exit_funcs);
  53         __on_exit_funcs[__on_exit_count] = function;
  54         __on_exit_args[__on_exit_count++] = arg;
  55         return 0;
  56 }
  57
  58 static void __handle_on_exit_funcs(void)
  59 {
  60         int i;
  61         for (i = 0; i < __on_exit_count; i++)
  62                 __on_exit_funcs[i] (__exitcode, __on_exit_args[i]);
  63 }
  64 #endif
  65
  66 enum write_mode_t {
  67         WRITE_FORCE,
  68         WRITE_APPEND
  69 };
  70
  71 struct perf_record {
  72         struct perf_tool        tool;
  73         struct perf_record_opts opts;
  74         u64                     bytes_written;
  75         const char              *output_name;
  76         struct perf_evlist      *evlist;
  77         struct perf_session     *session;
  78         const char              *progname;
  79         int                     output;
  80         unsigned int            page_size;
  81         int                     realtime_prio;
  82         enum write_mode_t       write_mode;
  83         bool                    no_buildid;
  84         bool                    no_buildid_cache;
  85         bool                    force;
  86         bool                    file_new;
  87         bool                    append_file;
  88         long                    samples;
  89         off_t                   post_processing_offset;
  90 };
  91
  92 static void advance_output(struct perf_record *rec, size_t size)
  93 {
  94         rec->bytes_written += size;
  95 }
  96
  97 static int write_output(struct perf_record *rec, void *buf, size_t size)
  98 {
  99         while (size) {
 100                 int ret = write(rec->output, buf, size);
 101
 102                 if (ret < 0) {
 103                         pr_err("failed to write\n");
 104                         return -1;
 105                 }
 106
 107                 size -= ret;
 108                 buf += ret;
 109
 110                 rec->bytes_written += ret;
 111         }
 112
 113         return 0;
 114 }
 115
 116 static int process_synthesized_event(struct perf_tool *tool,
 117                                      union perf_event *event,
 118                                      struct perf_sample *sample __maybe_unused,
 119                                      struct machine *machine __maybe_unused)
 120 {
 121         struct perf_record *rec = container_of(tool, struct perf_record, tool);
 122         if (write_output(rec, event, event->header.size) < 0)
 123                 return -1;
 124
 125         return 0;
 126 }
 127
 128 static int perf_record__mmap_read(struct perf_record *rec,
 129                                    struct perf_mmap *md)
 130 {
 131         unsigned int head = perf_mmap__read_head(md);
 132         unsigned int old = md->prev;
 133         unsigned char *data = md->base + rec->page_size;
 134         unsigned long size;
 135         void *buf;
 136         int rc = 0;
 137
 138         if (old == head)
 139                 return 0;
 140
 141         rec->samples++;
 142
 143         size = head - old;
 144
 145         if ((old & md->mask) + size != (head & md->mask)) {
 146                 buf = &data[old & md->mask];
 147                 size = md->mask + 1 - (old & md->mask);
 148                 old += size;
 149
 150                 if (write_output(rec, buf, size) < 0) {
 151                         rc = -1;
 152                         goto out;
 153                 }
 154         }
 155
 156         buf = &data[old & md->mask];
 157         size = head - old;
 158         old += size;
 159
 160         if (write_output(rec, buf, size) < 0) {
 161                 rc = -1;
 162                 goto out;
 163         }
 164
 165         md->prev = old;
 166         perf_mmap__write_tail(md, old);
 167
 168 out:
 169         return rc;
 170 }
 171
 172 static volatile int done = 0;
 173 static volatile int signr = -1;
 174 static volatile int child_finished = 0;
 175
 176 static void sig_handler(int sig)
 177 {
 178         if (sig == SIGCHLD)
 179                 child_finished = 1;
 180
 181         done = 1;
 182         signr = sig;
 183 }
 184
 185 static void perf_record__sig_exit(int exit_status __maybe_unused, void *arg)
 186 {
 187         struct perf_record *rec = arg;
 188         int status;
 189
 190         if (rec->evlist->workload.pid > 0) {
 191                 if (!child_finished)
 192                         kill(rec->evlist->workload.pid, SIGTERM);
 193
 194                 wait(&status);
 195                 if (WIFSIGNALED(status))
 196                         psignal(WTERMSIG(status), rec->progname);
 197         }
 198
 199         if (signr == -1 || signr == SIGUSR1)
 200                 return;
 201
 202         signal(signr, SIG_DFL);
 203         kill(getpid(), signr);
 204 }
 205
 206 static bool perf_evlist__equal(struct perf_evlist *evlist,
 207                                struct perf_evlist *other)
 208 {
 209         struct perf_evsel *pos, *pair;
 210
 211         if (evlist->nr_entries != other->nr_entries)
 212                 return false;
 213
 214         pair = perf_evlist__first(other);
 215
 216         list_for_each_entry(pos, &evlist->entries, node) {
 217                 if (memcmp(&pos->attr, &pair->attr, sizeof(pos->attr) != 0))
 218                         return false;
 219                 pair = perf_evsel__next(pair);
 220         }
 221
 222         return true;
 223 }
 224
 225 static int perf_record__open(struct perf_record *rec)
 226 {
 227         char msg[512];
 228         struct perf_evsel *pos;
 229         struct perf_evlist *evlist = rec->evlist;
 230         struct perf_session *session = rec->session;
 231         struct perf_record_opts *opts = &rec->opts;
 232         int rc = 0;
 233
 234         perf_evlist__config(evlist, opts);
 235
 236         list_for_each_entry(pos, &evlist->entries, node) {
 237 try_again:
 238                 if (perf_evsel__open(pos, evlist->cpus, evlist->threads) < 0) {
 239                         if (perf_evsel__fallback(pos, errno, msg, sizeof(msg))) {
 240                                 if (verbose)
 241                                         ui__warning("%s\n", msg);
 242                                 goto try_again;
 243                         }
 244
 245                         rc = -errno;
 246                         perf_evsel__open_strerror(pos, &opts->target,
 247                                                   errno, msg, sizeof(msg));
 248                         ui__error("%s\n", msg);
 249                         goto out;
 250                 }
 251         }
 252
 253         if (perf_evlist__apply_filters(evlist)) {
 254                 error("failed to set filter with %d (%s)\n", errno,
 255                         strerror(errno));
 256                 rc = -1;
 257                 goto out;
 258         }
 259
 260         if (perf_evlist__mmap(evlist, opts->mmap_pages, false) < 0) {
 261                 if (errno == EPERM) {
 262                         pr_err("Permission error mapping pages.\n"
 263                                "Consider increasing "
 264                                "/proc/sys/kernel/perf_event_mlock_kb,\n"
 265                                "or try again with a smaller value of -m/--mmap_pages.\n"
 266                                "(current value: %d)\n", opts->mmap_pages);
 267                         rc = -errno;
 268                 } else if (!is_power_of_2(opts->mmap_pages) &&
 269                            (opts->mmap_pages != UINT_MAX)) {
 270                         pr_err("--mmap_pages/-m value must be a power of two.");
 271                         rc = -EINVAL;
 272                 } else {
 273                         pr_err("failed to mmap with %d (%s)\n", errno, strerror(errno));
 274                         rc = -errno;
 275                 }
 276                 goto out;
 277         }
 278
 279         if (rec->file_new)
 280                 session->evlist = evlist;
 281         else {
 282                 if (!perf_evlist__equal(session->evlist, evlist)) {
 283                         fprintf(stderr, "incompatible append\n");
 284                         rc = -1;
 285                         goto out;
 286                 }
 287         }
 288
 289         perf_session__set_id_hdr_size(session);
 290 out:
 291         return rc;
 292 }
 293
 294 static int process_buildids(struct perf_record *rec)
 295 {
 296         u64 size = lseek(rec->output, 0, SEEK_CUR);
 297
 298         if (size == 0)
 299                 return 0;
 300
 301         rec->session->fd = rec->output;
 302         return __perf_session__process_events(rec->session, rec->post_processing_offset,
 303                                               size - rec->post_processing_offset,
 304                                               size, &build_id__mark_dso_hit_ops);
 305 }
 306
 307 static void perf_record__exit(int status, void *arg)
 308 {
 309         struct perf_record *rec = arg;
 310
 311         if (status != 0)
 312                 return;
 313
 314         if (!rec->opts.pipe_output) {
 315                 rec->session->header.data_size += rec->bytes_written;
 316
 317                 if (!rec->no_buildid)
 318                         process_buildids(rec);
 319                 perf_session__write_header(rec->session, rec->evlist,
 320                                            rec->output, true);
 321                 perf_session__delete(rec->session);
 322                 perf_evlist__delete(rec->evlist);
 323                 symbol__exit();
 324         }
 325 }
 326
 327 static void perf_event__synthesize_guest_os(struct machine *machine, void *data)
 328 {
 329         int err;
 330         struct perf_tool *tool = data;
 331         /*
 332          *As for guest kernel when processing subcommand record&report,
 333          *we arrange module mmap prior to guest kernel mmap and trigger
 334          *a preload dso because default guest module symbols are loaded
 335          *from guest kallsyms instead of /lib/modules/XXX/XXX. This
 336          *method is used to avoid symbol missing when the first addr is
 337          *in module instead of in guest kernel.
 338          */
 339         err = perf_event__synthesize_modules(tool, process_synthesized_event,
 340                                              machine);
 341         if (err < 0)
 342                 pr_err("Couldn't record guest kernel [%d]'s reference"
 343                        " relocation symbol.\n", machine->pid);
 344
 345         /*
 346          * We use _stext for guest kernel because guest kernel's /proc/kallsyms
 347          * have no _text sometimes.
 348          */
 349         err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 350                                                  machine, "_text");
 351         if (err < 0)
 352                 err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 353                                                          machine, "_stext");
 354         if (err < 0)
 355                 pr_err("Couldn't record guest kernel [%d]'s reference"
 356                        " relocation symbol.\n", machine->pid);
 357 }
 358
 359 static struct perf_event_header finished_round_event = {
 360         .size = sizeof(struct perf_event_header),
 361         .type = PERF_RECORD_FINISHED_ROUND,
 362 };
 363
 364 static int perf_record__mmap_read_all(struct perf_record *rec)
 365 {
 366         int i;
 367         int rc = 0;
 368
 369         for (i = 0; i < rec->evlist->nr_mmaps; i++) {
 370                 if (rec->evlist->mmap[i].base) {
 371                         if (perf_record__mmap_read(rec, &rec->evlist->mmap[i]) != 0) {
 372                                 rc = -1;
 373                                 goto out;
 374                         }
 375                 }
 376         }
 377
 378         if (perf_header__has_feat(&rec->session->header, HEADER_TRACING_DATA))
 379                 rc = write_output(rec, &finished_round_event,
 380                                   sizeof(finished_round_event));
 381
 382 out:
 383         return rc;
 384 }
 385
 386 static int __cmd_record(struct perf_record *rec, int argc, const char **argv)
 387 {
 388         struct stat st;
 389         int flags;
 390         int err, output, feat;
 391         unsigned long waking = 0;
 392         const bool forks = argc > 0;
 393         struct machine *machine;
 394         struct perf_tool *tool = &rec->tool;
 395         struct perf_record_opts *opts = &rec->opts;
 396         struct perf_evlist *evsel_list = rec->evlist;
 397         const char *output_name = rec->output_name;
 398         struct perf_session *session;
 399         bool disabled = false;
 400
 401         rec->progname = argv[0];
 402
 403         rec->page_size = sysconf(_SC_PAGE_SIZE);
 404
 405         on_exit(perf_record__sig_exit, rec);
 406         signal(SIGCHLD, sig_handler);
 407         signal(SIGINT, sig_handler);
 408         signal(SIGUSR1, sig_handler);
 409
 410         if (!output_name) {
 411                 if (!fstat(STDOUT_FILENO, &st) && S_ISFIFO(st.st_mode))
 412                         opts->pipe_output = true;
 413                 else
 414                         rec->output_name = output_name = "perf.data";
 415         }
 416         if (output_name) {
 417                 if (!strcmp(output_name, "-"))
 418                         opts->pipe_output = true;
 419                 else if (!stat(output_name, &st) && st.st_size) {
 420                         if (rec->write_mode == WRITE_FORCE) {
 421                                 char oldname[PATH_MAX];
 422                                 snprintf(oldname, sizeof(oldname), "%s.old",
 423                                          output_name);
 424                                 unlink(oldname);
 425                                 rename(output_name, oldname);
 426                         }
 427                 } else if (rec->write_mode == WRITE_APPEND) {
 428                         rec->write_mode = WRITE_FORCE;
 429                 }
 430         }
 431
 432         flags = O_CREAT|O_RDWR;
 433         if (rec->write_mode == WRITE_APPEND)
 434                 rec->file_new = 0;
 435         else
 436                 flags |= O_TRUNC;
 437
 438         if (opts->pipe_output)
 439                 output = STDOUT_FILENO;
 440         else
 441                 output = open(output_name, flags, S_IRUSR | S_IWUSR);
 442         if (output < 0) {
 443                 perror("failed to create output file");
 444                 return -1;
 445         }
 446
 447         rec->output = output;
 448
 449         session = perf_session__new(output_name, O_WRONLY,
 450                                     rec->write_mode == WRITE_FORCE, false, NULL);
 451         if (session == NULL) {
 452                 pr_err("Not enough memory for reading perf file header\n");
 453                 return -1;
 454         }
 455
 456         rec->session = session;
 457
 458         for (feat = HEADER_FIRST_FEATURE; feat < HEADER_LAST_FEATURE; feat++)
 459                 perf_header__set_feat(&session->header, feat);
 460
 461         if (rec->no_buildid)
 462                 perf_header__clear_feat(&session->header, HEADER_BUILD_ID);
 463
 464         if (!have_tracepoints(&evsel_list->entries))
 465                 perf_header__clear_feat(&session->header, HEADER_TRACING_DATA);
 466
 467         if (!rec->opts.branch_stack)
 468                 perf_header__clear_feat(&session->header, HEADER_BRANCH_STACK);
 469
 470         if (!rec->file_new) {
 471                 err = perf_session__read_header(session, output);
 472                 if (err < 0)
 473                         goto out_delete_session;
 474         }
 475
 476         if (forks) {
 477                 err = perf_evlist__prepare_workload(evsel_list, &opts->target,
 478                                                     opts, argv);
 479                 if (err < 0) {
 480                         pr_err("Couldn't run the workload!\n");
 481                         goto out_delete_session;
 482                 }
 483         }
 484
 485         if (perf_record__open(rec) != 0) {
 486                 err = -1;
 487                 goto out_delete_session;
 488         }
 489
 490         if (!evsel_list->nr_groups)
 491                 perf_header__clear_feat(&session->header, HEADER_GROUP_DESC);
 492
 493         /*
 494          * perf_session__delete(session) will be called at perf_record__exit()
 495          */
 496         on_exit(perf_record__exit, rec);
 497
 498         if (opts->pipe_output) {
 499                 err = perf_header__write_pipe(output);
 500                 if (err < 0)
 501                         goto out_delete_session;
 502         } else if (rec->file_new) {
 503                 err = perf_session__write_header(session, evsel_list,
 504                                                  output, false);
 505                 if (err < 0)
 506                         goto out_delete_session;
 507         }
 508
 509         if (!rec->no_buildid
 510             && !perf_header__has_feat(&session->header, HEADER_BUILD_ID)) {
 511                 pr_err("Couldn't generate buildids. "
 512                        "Use --no-buildid to profile anyway.\n");
 513                 err = -1;
 514                 goto out_delete_session;
 515         }
 516
 517         rec->post_processing_offset = lseek(output, 0, SEEK_CUR);
 518
 519         machine = &session->machines.host;
 520
 521         if (opts->pipe_output) {
 522                 err = perf_event__synthesize_attrs(tool, session,
 523                                                    process_synthesized_event);
 524                 if (err < 0) {
 525                         pr_err("Couldn't synthesize attrs.\n");
 526                         goto out_delete_session;
 527                 }
 528
 529                 err = perf_event__synthesize_event_types(tool, process_synthesized_event,
 530                                                          machine);
 531                 if (err < 0) {
 532                         pr_err("Couldn't synthesize event_types.\n");
 533                         goto out_delete_session;
 534                 }
 535
 536                 if (have_tracepoints(&evsel_list->entries)) {
 537                         /*
 538                          * FIXME err <= 0 here actually means that
 539                          * there were no tracepoints so its not really
 540                          * an error, just that we don't need to
 541                          * synthesize anything.  We really have to
 542                          * return this more properly and also
 543                          * propagate errors that now are calling die()
 544                          */
 545                         err = perf_event__synthesize_tracing_data(tool, output, evsel_list,
 546                                                                   process_synthesized_event);
 547                         if (err <= 0) {
 548                                 pr_err("Couldn't record tracing data.\n");
 549                                 goto out_delete_session;
 550                         }
 551                         advance_output(rec, err);
 552                 }
 553         }
 554
 555         err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 556                                                  machine, "_text");
 557         if (err < 0)
 558                 err = perf_event__synthesize_kernel_mmap(tool, process_synthesized_event,
 559                                                          machine, "_stext");
 560         if (err < 0)
 561                 pr_err("Couldn't record kernel reference relocation symbol\n"
 562                        "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
 563                        "Check /proc/kallsyms permission or run as root.\n");
 564
 565         err = perf_event__synthesize_modules(tool, process_synthesized_event,
 566                                              machine);
 567         if (err < 0)
 568                 pr_err("Couldn't record kernel module information.\n"
 569                        "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
 570                        "Check /proc/modules permission or run as root.\n");
 571
 572         if (perf_guest) {
 573                 machines__process_guests(&session->machines,
 574                                          perf_event__synthesize_guest_os, tool);
 575         }
 576
 577         if (perf_target__has_task(&opts->target))
 578                 err = perf_event__synthesize_thread_map(tool, evsel_list->threads,
 579                                                   process_synthesized_event,
 580                                                   machine);
 581         else if (perf_target__has_cpu(&opts->target))
 582                 err = perf_event__synthesize_threads(tool, process_synthesized_event,
 583                                                machine);
 584         else /* command specified */
 585                 err = 0;
 586
 587         if (err != 0)
 588                 goto out_delete_session;
 589
 590         if (rec->realtime_prio) {
 591                 struct sched_param param;
 592
 593                 param.sched_priority = rec->realtime_prio;
 594                 if (sched_setscheduler(0, SCHED_FIFO, &param)) {
 595                         pr_err("Could not set realtime priority.\n");
 596                         err = -1;
 597                         goto out_delete_session;
 598                 }
 599         }
 600
 601         /*
 602          * When perf is starting the traced process, all the events
 603          * (apart from group members) have enable_on_exec=1 set,
 604          * so don't spoil it by prematurely enabling them.
 605          */
 606         if (!perf_target__none(&opts->target))
 607                 perf_evlist__enable(evsel_list);
 608
 609         /*
 610          * Let the child rip
 611          */
 612         if (forks)
 613                 perf_evlist__start_workload(evsel_list);
 614
 615         for (;;) {
 616                 int hits = rec->samples;
 617
 618                 if (perf_record__mmap_read_all(rec) < 0) {
 619                         err = -1;
 620                         goto out_delete_session;
 621                 }
 622
 623                 if (hits == rec->samples) {
 624                         if (done)
 625                                 break;
 626                         err = poll(evsel_list->pollfd, evsel_list->nr_fds, -1);
 627                         waking++;
 628                 }
 629
 630                 /*
 631                  * When perf is starting the traced process, at the end events
 632                  * die with the process and we wait for that. Thus no need to
 633                  * disable events in this case.
 634                  */
 635                 if (done && !disabled && !perf_target__none(&opts->target)) {
 636                         perf_evlist__disable(evsel_list);
 637                         disabled = true;
 638                 }
 639         }
 640
 641         if (quiet || signr == SIGUSR1)
 642                 return 0;
 643
 644         fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
 645
 646         /*
 647          * Approximate RIP event size: 24 bytes.
 648          */
 649         fprintf(stderr,
 650                 "[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64 " samples) ]\n",
 651                 (double)rec->bytes_written / 1024.0 / 1024.0,
 652                 output_name,
 653                 rec->bytes_written / 24);
 654
 655         return 0;
 656
 657 out_delete_session:
 658         perf_session__delete(session);
 659         return err;
 660 }
 661
 662 #define BRANCH_OPT(n, m) \
 663         { .name = n, .mode = (m) }
 664
 665 #define BRANCH_END { .name = NULL }
 666
 667 struct branch_mode {
 668         const char *name;
 669         int mode;
 670 };
 671
 672 static const struct branch_mode branch_modes[] = {
 673         BRANCH_OPT("u", PERF_SAMPLE_BRANCH_USER),
 674         BRANCH_OPT("k", PERF_SAMPLE_BRANCH_KERNEL),
 675         BRANCH_OPT("hv", PERF_SAMPLE_BRANCH_HV),
 676         BRANCH_OPT("any", PERF_SAMPLE_BRANCH_ANY),
 677         BRANCH_OPT("any_call", PERF_SAMPLE_BRANCH_ANY_CALL),
 678         BRANCH_OPT("any_ret", PERF_SAMPLE_BRANCH_ANY_RETURN),
 679         BRANCH_OPT("ind_call", PERF_SAMPLE_BRANCH_IND_CALL),
 680         BRANCH_END
 681 };
 682
 683 static int
 684 parse_branch_stack(const struct option *opt, const char *str, int unset)
 685 {
 686 #define ONLY_PLM \
 687         (PERF_SAMPLE_BRANCH_USER        |\
 688          PERF_SAMPLE_BRANCH_KERNEL      |\
 689          PERF_SAMPLE_BRANCH_HV)
 690
 691         uint64_t *mode = (uint64_t *)opt->value;
 692         const struct branch_mode *br;
 693         char *s, *os = NULL, *p;
 694         int ret = -1;
 695
 696         if (unset)
 697                 return 0;
 698
 699         /*
 700          * cannot set it twice, -b + --branch-filter for instance
 701          */
 702         if (*mode)
 703                 return -1;
 704
 705         /* str may be NULL in case no arg is passed to -b */
 706         if (str) {
 707                 /* because str is read-only */
 708                 s = os = strdup(str);
 709                 if (!s)
 710                         return -1;
 711
 712                 for (;;) {
 713                         p = strchr(s, ',');
 714                         if (p)
 715                                 *p = '\0';
 716
 717                         for (br = branch_modes; br->name; br++) {
 718                                 if (!strcasecmp(s, br->name))
 719                                         break;
 720                         }
 721                         if (!br->name) {
 722                                 ui__warning("unknown branch filter %s,"
 723                                             " check man page\n", s);
 724                                 goto error;
 725                         }
 726
 727                         *mode |= br->mode;
 728
 729                         if (!p)
 730                                 break;
 731
 732                         s = p + 1;
 733                 }
 734         }
 735         ret = 0;
 736
 737         /* default to any branch */
 738         if ((*mode & ~ONLY_PLM) == 0) {
 739                 *mode = PERF_SAMPLE_BRANCH_ANY;
 740         }
 741 error:
 742         free(os);
 743         return ret;
 744 }
 745
 746 #ifdef LIBUNWIND_SUPPORT
 747 static int get_stack_size(char *str, unsigned long *_size)
 748 {
 749         char *endptr;
 750         unsigned long size;
 751         unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
 752
 753         size = strtoul(str, &endptr, 0);
 754
 755         do {
 756                 if (*endptr)
 757                         break;
 758
 759                 size = round_up(size, sizeof(u64));
 760                 if (!size || size > max_size)
 761                         break;
 762
 763                 *_size = size;
 764                 return 0;
 765
 766         } while (0);
 767
 768         pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
 769                max_size, str);
 770         return -1;
 771 }
 772 #endif /* LIBUNWIND_SUPPORT */
 773
 774 int record_parse_callchain_opt(const struct option *opt,
 775                                const char *arg, int unset)
 776 {
 777         struct perf_record_opts *opts = opt->value;
 778         char *tok, *name, *saveptr = NULL;
 779         char *buf;
 780         int ret = -1;
 781
 782         /* --no-call-graph */
 783         if (unset)
 784                 return 0;
 785
 786         /* We specified default option if none is provided. */
 787         BUG_ON(!arg);
 788
 789         /* We need buffer that we know we can write to. */
 790         buf = malloc(strlen(arg) + 1);
 791         if (!buf)
 792                 return -ENOMEM;
 793
 794         strcpy(buf, arg);
 795
 796         tok = strtok_r((char *)buf, ",", &saveptr);
 797         name = tok ? : (char *)buf;
 798
 799         do {
 800                 /* Framepointer style */
 801                 if (!strncmp(name, "fp", sizeof("fp"))) {
 802                         if (!strtok_r(NULL, ",", &saveptr)) {
 803                                 opts->call_graph = CALLCHAIN_FP;
 804                                 ret = 0;
 805                         } else
 806                                 pr_err("callchain: No more arguments "
 807                                        "needed for -g fp\n");
 808                         break;
 809
 810 #ifdef LIBUNWIND_SUPPORT
 811                 /* Dwarf style */
 812                 } else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
 813                         const unsigned long default_stack_dump_size = 8192;
 814
 815                         ret = 0;
 816                         opts->call_graph = CALLCHAIN_DWARF;
 817                         opts->stack_dump_size = default_stack_dump_size;
 818
 819                         tok = strtok_r(NULL, ",", &saveptr);
 820                         if (tok) {
 821                                 unsigned long size = 0;
 822
 823                                 ret = get_stack_size(tok, &size);
 824                                 opts->stack_dump_size = size;
 825                         }
 826
 827                         if (!ret)
 828                                 pr_debug("callchain: stack dump size %d\n",
 829                                          opts->stack_dump_size);
 830 #endif /* LIBUNWIND_SUPPORT */
 831                 } else {
 832                         pr_err("callchain: Unknown -g option "
 833                                "value: %s\n", arg);
 834                         break;
 835                 }
 836
 837         } while (0);
 838
 839         free(buf);
 840
 841         if (!ret)
 842                 pr_debug("callchain: type %d\n", opts->call_graph);
 843
 844         return ret;
 845 }
 846
 847 static const char * const record_usage[] = {
 848         "perf record [<options>] [<command>]",
 849         "perf record [<options>] -- <command> [<options>]",
 850         NULL
 851 };
 852
 853 /*
 854  * XXX Ideally would be local to cmd_record() and passed to a perf_record__new
 855  * because we need to have access to it in perf_record__exit, that is called
 856  * after cmd_record() exits, but since record_options need to be accessible to
 857  * builtin-script, leave it here.
 858  *
 859  * At least we don't ouch it in all the other functions here directly.
 860  *
 861  * Just say no to tons of global variables, sigh.
 862  */
 863 static struct perf_record record = {
 864         .opts = {
 865                 .mmap_pages          = UINT_MAX,
 866                 .user_freq           = UINT_MAX,
 867                 .user_interval       = ULLONG_MAX,
 868                 .freq                = 4000,
 869                 .target              = {
 870                         .uses_mmap   = true,
 871                 },
 872         },
 873         .write_mode = WRITE_FORCE,
 874         .file_new   = true,
 875 };
 876
 877 #define CALLCHAIN_HELP "do call-graph (stack chain/backtrace) recording: "
 878
 879 #ifdef LIBUNWIND_SUPPORT
 880 const char record_callchain_help[] = CALLCHAIN_HELP "[fp] dwarf";
 881 #else
 882 const char record_callchain_help[] = CALLCHAIN_HELP "[fp]";
 883 #endif
 884
 885 /*
 886  * XXX Will stay a global variable till we fix builtin-script.c to stop messing
 887  * with it and switch to use the library functions in perf_evlist that came
 888  * from builtin-record.c, i.e. use perf_record_opts,
 889  * perf_evlist__prepare_workload, etc instead of fork+exec'in 'perf record',
 890  * using pipes, etc.
 891  */
 892 const struct option record_options[] = {
 893         OPT_CALLBACK('e', "event", &record.evlist, "event",
 894                      "event selector. use 'perf list' to list available events",
 895                      parse_events_option),
 896         OPT_CALLBACK(0, "filter", &record.evlist, "filter",
 897                      "event filter", parse_filter),
 898         OPT_STRING('p', "pid", &record.opts.target.pid, "pid",
 899                     "record events on existing process id"),
 900         OPT_STRING('t', "tid", &record.opts.target.tid, "tid",
 901                     "record events on existing thread id"),
 902         OPT_INTEGER('r', "realtime", &record.realtime_prio,
 903                     "collect data with this RT SCHED_FIFO priority"),
 904         OPT_BOOLEAN('D', "no-delay", &record.opts.no_delay,
 905                     "collect data without buffering"),
 906         OPT_BOOLEAN('R', "raw-samples", &record.opts.raw_samples,
 907                     "collect raw sample records from all opened counters"),
 908         OPT_BOOLEAN('a', "all-cpus", &record.opts.target.system_wide,
 909                             "system-wide collection from all CPUs"),
 910         OPT_BOOLEAN('A', "append", &record.append_file,
 911                             "append to the output file to do incremental profiling"),
 912         OPT_STRING('C', "cpu", &record.opts.target.cpu_list, "cpu",
 913                     "list of cpus to monitor"),
 914         OPT_BOOLEAN('f', "force", &record.force,
 915                         "overwrite existing data file (deprecated)"),
 916         OPT_U64('c', "count", &record.opts.user_interval, "event period to sample"),
 917         OPT_STRING('o', "output", &record.output_name, "file",
 918                     "output file name"),
 919         OPT_BOOLEAN('i', "no-inherit", &record.opts.no_inherit,
 920                     "child tasks do not inherit counters"),
 921         OPT_UINTEGER('F', "freq", &record.opts.user_freq, "profile at this frequency"),
 922         OPT_UINTEGER('m', "mmap-pages", &record.opts.mmap_pages,
 923                      "number of mmap data pages"),
 924         OPT_BOOLEAN(0, "group", &record.opts.group,
 925                     "put the counters into a counter group"),
 926         OPT_CALLBACK_DEFAULT('g', "call-graph", &record.opts,
 927                              "mode[,dump_size]", record_callchain_help,
 928                              &record_parse_callchain_opt, "fp"),
 929         OPT_INCR('v', "verbose", &verbose,
 930                     "be more verbose (show counter open errors, etc)"),
 931         OPT_BOOLEAN('q', "quiet", &quiet, "don't print any message"),
 932         OPT_BOOLEAN('s', "stat", &record.opts.inherit_stat,
 933                     "per thread counts"),
 934         OPT_BOOLEAN('d', "data", &record.opts.sample_address,
 935                     "Sample addresses"),
 936         OPT_BOOLEAN('T', "timestamp", &record.opts.sample_time, "Sample timestamps"),
 937         OPT_BOOLEAN('P', "period", &record.opts.period, "Sample period"),
 938         OPT_BOOLEAN('n', "no-samples", &record.opts.no_samples,
 939                     "don't sample"),
 940         OPT_BOOLEAN('N', "no-buildid-cache", &record.no_buildid_cache,
 941                     "do not update the buildid cache"),
 942         OPT_BOOLEAN('B', "no-buildid", &record.no_buildid,
 943                     "do not collect buildids in perf.data"),
 944         OPT_CALLBACK('G', "cgroup", &record.evlist, "name",
 945                      "monitor event in cgroup name only",
 946                      parse_cgroups),
 947         OPT_STRING('u', "uid", &record.opts.target.uid_str, "user",
 948                    "user to profile"),
 949
 950         OPT_CALLBACK_NOOPT('b', "branch-any", &record.opts.branch_stack,
 951                      "branch any", "sample any taken branches",
 952                      parse_branch_stack),
 953
 954         OPT_CALLBACK('j', "branch-filter", &record.opts.branch_stack,
 955                      "branch filter mask", "branch stack filter modes",
 956                      parse_branch_stack),
 957         OPT_END()
 958 };
 959
 960 int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
 961 {
 962         int err = -ENOMEM;
 963         struct perf_evsel *pos;
 964         struct perf_evlist *evsel_list;
 965         struct perf_record *rec = &record;
 966         char errbuf[BUFSIZ];
 967
 968         evsel_list = perf_evlist__new();
 969         if (evsel_list == NULL)
 970                 return -ENOMEM;
 971
 972         rec->evlist = evsel_list;
 973
 974         argc = parse_options(argc, argv, record_options, record_usage,
 975                             PARSE_OPT_STOP_AT_NON_OPTION);
 976         if (!argc && perf_target__none(&rec->opts.target))
 977                 usage_with_options(record_usage, record_options);
 978
 979         if (rec->force && rec->append_file) {
 980                 ui__error("Can't overwrite and append at the same time."
 981                           " You need to choose between -f and -A");
 982                 usage_with_options(record_usage, record_options);
 983         } else if (rec->append_file) {
 984                 rec->write_mode = WRITE_APPEND;
 985         } else {
 986                 rec->write_mode = WRITE_FORCE;
 987         }
 988
 989         if (nr_cgroups && !rec->opts.target.system_wide) {
 990                 ui__error("cgroup monitoring only available in"
 991                           " system-wide mode\n");
 992                 usage_with_options(record_usage, record_options);
 993         }
 994
 995         symbol__init();
 996
 997         if (symbol_conf.kptr_restrict)
 998                 pr_warning(
 999 "WARNING: Kernel address maps (/proc/{kallsyms,modules}) are restricted,\n"
1000 "check /proc/sys/kernel/kptr_restrict.\n\n"
1001 "Samples in kernel functions may not be resolved if a suitable vmlinux\n"
1002 "file is not found in the buildid cache or in the vmlinux path.\n\n"
1003 "Samples in kernel modules won't be resolved at all.\n\n"
1004 "If some relocation was applied (e.g. kexec) symbols may be misresolved\n"
1005 "even with a suitable vmlinux or kallsyms file.\n\n");
1006
1007         if (rec->no_buildid_cache || rec->no_buildid)
1008                 disable_buildid_cache();
1009
1010         if (evsel_list->nr_entries == 0 &&
1011             perf_evlist__add_default(evsel_list) < 0) {
1012                 pr_err("Not enough memory for event selector list\n");
1013                 goto out_symbol_exit;
1014         }
1015
1016         err = perf_target__validate(&rec->opts.target);
1017         if (err) {
1018                 perf_target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
1019                 ui__warning("%s", errbuf);
1020         }
1021
1022         err = perf_target__parse_uid(&rec->opts.target);
1023         if (err) {
1024                 int saved_errno = errno;
1025
1026                 perf_target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
1027                 ui__error("%s", errbuf);
1028
1029                 err = -saved_errno;
1030                 goto out_free_fd;
1031         }
1032
1033         err = -ENOMEM;
1034         if (perf_evlist__create_maps(evsel_list, &rec->opts.target) < 0)
1035                 usage_with_options(record_usage, record_options);
1036
1037         list_for_each_entry(pos, &evsel_list->entries, node) {
1038                 if (perf_header__push_event(pos->attr.config, perf_evsel__name(pos)))
1039                         goto out_free_fd;
1040         }
1041
1042         if (rec->opts.user_interval != ULLONG_MAX)
1043                 rec->opts.default_interval = rec->opts.user_interval;
1044         if (rec->opts.user_freq != UINT_MAX)
1045                 rec->opts.freq = rec->opts.user_freq;
1046
1047         /*
1048          * User specified count overrides default frequency.
1049          */
1050         if (rec->opts.default_interval)
1051                 rec->opts.freq = 0;
1052         else if (rec->opts.freq) {
1053                 rec->opts.default_interval = rec->opts.freq;
1054         } else {
1055                 ui__error("frequency and count are zero, aborting\n");
1056                 err = -EINVAL;
1057                 goto out_free_fd;
1058         }
1059
1060         err = __cmd_record(&record, argc, argv);
1061 out_free_fd:
1062         perf_evlist__delete_maps(evsel_list);
1063 out_symbol_exit:
1064         symbol__exit();
1065         return err;
1066 }