SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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/util.h"
  13 #include "util/parse-options.h"
  14 #include "util/parse-events.h"
  15 #include "util/string.h"
  16
  17 #include "util/header.h"
  18 #include "util/event.h"
  19 #include "util/debug.h"
  20
  21 #include <unistd.h>
  22 #include <sched.h>
  23
  24 static int                      fd[MAX_NR_CPUS][MAX_COUNTERS];
  25
  26 static long                     default_interval                =      0;
  27
  28 static int                      nr_cpus                         =      0;
  29 static unsigned int             page_size;
  30 static unsigned int             mmap_pages                      =    128;
  31 static int                      freq                            =   1000;
  32 static int                      output;
  33 static const char               *output_name                    = "perf.data";
  34 static int                      group                           =      0;
  35 static unsigned int             realtime_prio                   =      0;
  36 static int                      raw_samples                     =      0;
  37 static int                      system_wide                     =      0;
  38 static int                      profile_cpu                     =     -1;
  39 static pid_t                    target_pid                      =     -1;
  40 static pid_t                    child_pid                       =     -1;
  41 static int                      inherit                         =      1;
  42 static int                      force                           =      0;
  43 static int                      append_file                     =      0;
  44 static int                      call_graph                      =      0;
  45 static int                      inherit_stat                    =      0;
  46 static int                      no_samples                      =      0;
  47 static int                      sample_address                  =      0;
  48 static int                      multiplex                       =      0;
  49 static int                      multiplex_fd                    =     -1;
  50
  51 static long                     samples                         =      0;
  52 static struct timeval           last_read;
  53 static struct timeval           this_read;
  54
  55 static u64                      bytes_written                   =      0;
  56
  57 static struct pollfd            event_array[MAX_NR_CPUS * MAX_COUNTERS];
  58
  59 static int                      nr_poll                         =      0;
  60 static int                      nr_cpu                          =      0;
  61
  62 static int                      file_new                        =      1;
  63
  64 struct perf_header              *header                         =   NULL;
  65
  66 struct mmap_data {
  67         int                     counter;
  68         void                    *base;
  69         unsigned int            mask;
  70         unsigned int            prev;
  71 };
  72
  73 static struct mmap_data         mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
  74
  75 static unsigned long mmap_read_head(struct mmap_data *md)
  76 {
  77         struct perf_event_mmap_page *pc = md->base;
  78         long head;
  79
  80         head = pc->data_head;
  81         rmb();
  82
  83         return head;
  84 }
  85
  86 static void mmap_write_tail(struct mmap_data *md, unsigned long tail)
  87 {
  88         struct perf_event_mmap_page *pc = md->base;
  89
  90         /*
  91          * ensure all reads are done before we write the tail out.
  92          */
  93         /* mb(); */
  94         pc->data_tail = tail;
  95 }
  96
  97 static void write_output(void *buf, size_t size)
  98 {
  99         while (size) {
 100                 int ret = write(output, buf, size);
 101
 102                 if (ret < 0)
 103                         die("failed to write");
 104
 105                 size -= ret;
 106                 buf += ret;
 107
 108                 bytes_written += ret;
 109         }
 110 }
 111
 112 static void mmap_read(struct mmap_data *md)
 113 {
 114         unsigned int head = mmap_read_head(md);
 115         unsigned int old = md->prev;
 116         unsigned char *data = md->base + page_size;
 117         unsigned long size;
 118         void *buf;
 119         int diff;
 120
 121         gettimeofday(&this_read, NULL);
 122
 123         /*
 124          * If we're further behind than half the buffer, there's a chance
 125          * the writer will bite our tail and mess up the samples under us.
 126          *
 127          * If we somehow ended up ahead of the head, we got messed up.
 128          *
 129          * In either case, truncate and restart at head.
 130          */
 131         diff = head - old;
 132         if (diff < 0) {
 133                 struct timeval iv;
 134                 unsigned long msecs;
 135
 136                 timersub(&this_read, &last_read, &iv);
 137                 msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
 138
 139                 fprintf(stderr, "WARNING: failed to keep up with mmap data."
 140                                 "  Last read %lu msecs ago.\n", msecs);
 141
 142                 /*
 143                  * head points to a known good entry, start there.
 144                  */
 145                 old = head;
 146         }
 147
 148         last_read = this_read;
 149
 150         if (old != head)
 151                 samples++;
 152
 153         size = head - old;
 154
 155         if ((old & md->mask) + size != (head & md->mask)) {
 156                 buf = &data[old & md->mask];
 157                 size = md->mask + 1 - (old & md->mask);
 158                 old += size;
 159
 160                 write_output(buf, size);
 161         }
 162
 163         buf = &data[old & md->mask];
 164         size = head - old;
 165         old += size;
 166
 167         write_output(buf, size);
 168
 169         md->prev = old;
 170         mmap_write_tail(md, old);
 171 }
 172
 173 static volatile int done = 0;
 174 static volatile int signr = -1;
 175
 176 static void sig_handler(int sig)
 177 {
 178         done = 1;
 179         signr = sig;
 180 }
 181
 182 static void sig_atexit(void)
 183 {
 184         if (child_pid != -1)
 185                 kill(child_pid, SIGTERM);
 186
 187         if (signr == -1)
 188                 return;
 189
 190         signal(signr, SIG_DFL);
 191         kill(getpid(), signr);
 192 }
 193
 194 static pid_t pid_synthesize_comm_event(pid_t pid, int full)
 195 {
 196         struct comm_event comm_ev;
 197         char filename[PATH_MAX];
 198         char bf[BUFSIZ];
 199         FILE *fp;
 200         size_t size = 0;
 201         DIR *tasks;
 202         struct dirent dirent, *next;
 203         pid_t tgid = 0;
 204
 205         snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
 206
 207         fp = fopen(filename, "r");
 208         if (fp == NULL) {
 209                 /*
 210                  * We raced with a task exiting - just return:
 211                  */
 212                 if (verbose)
 213                         fprintf(stderr, "couldn't open %s\n", filename);
 214                 return 0;
 215         }
 216
 217         memset(&comm_ev, 0, sizeof(comm_ev));
 218         while (!comm_ev.comm[0] || !comm_ev.pid) {
 219                 if (fgets(bf, sizeof(bf), fp) == NULL)
 220                         goto out_failure;
 221
 222                 if (memcmp(bf, "Name:", 5) == 0) {
 223                         char *name = bf + 5;
 224                         while (*name && isspace(*name))
 225                                 ++name;
 226                         size = strlen(name) - 1;
 227                         memcpy(comm_ev.comm, name, size++);
 228                 } else if (memcmp(bf, "Tgid:", 5) == 0) {
 229                         char *tgids = bf + 5;
 230                         while (*tgids && isspace(*tgids))
 231                                 ++tgids;
 232                         tgid = comm_ev.pid = atoi(tgids);
 233                 }
 234         }
 235
 236         comm_ev.header.type = PERF_RECORD_COMM;
 237         size = ALIGN(size, sizeof(u64));
 238         comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
 239
 240         if (!full) {
 241                 comm_ev.tid = pid;
 242
 243                 write_output(&comm_ev, comm_ev.header.size);
 244                 goto out_fclose;
 245         }
 246
 247         snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
 248
 249         tasks = opendir(filename);
 250         while (!readdir_r(tasks, &dirent, &next) && next) {
 251                 char *end;
 252                 pid = strtol(dirent.d_name, &end, 10);
 253                 if (*end)
 254                         continue;
 255
 256                 comm_ev.tid = pid;
 257
 258                 write_output(&comm_ev, comm_ev.header.size);
 259         }
 260         closedir(tasks);
 261
 262 out_fclose:
 263         fclose(fp);
 264         return tgid;
 265
 266 out_failure:
 267         fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
 268                 filename);
 269         exit(EXIT_FAILURE);
 270 }
 271
 272 static void pid_synthesize_mmap_samples(pid_t pid, pid_t tgid)
 273 {
 274         char filename[PATH_MAX];
 275         FILE *fp;
 276
 277         snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
 278
 279         fp = fopen(filename, "r");
 280         if (fp == NULL) {
 281                 /*
 282                  * We raced with a task exiting - just return:
 283                  */
 284                 if (verbose)
 285                         fprintf(stderr, "couldn't open %s\n", filename);
 286                 return;
 287         }
 288         while (1) {
 289                 char bf[BUFSIZ], *pbf = bf;
 290                 struct mmap_event mmap_ev = {
 291                         .header = { .type = PERF_RECORD_MMAP },
 292                 };
 293                 int n;
 294                 size_t size;
 295                 if (fgets(bf, sizeof(bf), fp) == NULL)
 296                         break;
 297
 298                 /* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
 299                 n = hex2u64(pbf, &mmap_ev.start);
 300                 if (n < 0)
 301                         continue;
 302                 pbf += n + 1;
 303                 n = hex2u64(pbf, &mmap_ev.len);
 304                 if (n < 0)
 305                         continue;
 306                 pbf += n + 3;
 307                 if (*pbf == 'x') { /* vm_exec */
 308                         char *execname = strchr(bf, '/');
 309
 310                         /* Catch VDSO */
 311                         if (execname == NULL)
 312                                 execname = strstr(bf, "[vdso]");
 313
 314                         if (execname == NULL)
 315                                 continue;
 316
 317                         size = strlen(execname);
 318                         execname[size - 1] = '\0'; /* Remove \n */
 319                         memcpy(mmap_ev.filename, execname, size);
 320                         size = ALIGN(size, sizeof(u64));
 321                         mmap_ev.len -= mmap_ev.start;
 322                         mmap_ev.header.size = (sizeof(mmap_ev) -
 323                                                (sizeof(mmap_ev.filename) - size));
 324                         mmap_ev.pid = tgid;
 325                         mmap_ev.tid = pid;
 326
 327                         write_output(&mmap_ev, mmap_ev.header.size);
 328                 }
 329         }
 330
 331         fclose(fp);
 332 }
 333
 334 static void synthesize_all(void)
 335 {
 336         DIR *proc;
 337         struct dirent dirent, *next;
 338
 339         proc = opendir("/proc");
 340
 341         while (!readdir_r(proc, &dirent, &next) && next) {
 342                 char *end;
 343                 pid_t pid, tgid;
 344
 345                 pid = strtol(dirent.d_name, &end, 10);
 346                 if (*end) /* only interested in proper numerical dirents */
 347                         continue;
 348
 349                 tgid = pid_synthesize_comm_event(pid, 1);
 350                 pid_synthesize_mmap_samples(pid, tgid);
 351         }
 352
 353         closedir(proc);
 354 }
 355
 356 static int group_fd;
 357
 358 static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int nr)
 359 {
 360         struct perf_header_attr *h_attr;
 361
 362         if (nr < header->attrs) {
 363                 h_attr = header->attr[nr];
 364         } else {
 365                 h_attr = perf_header_attr__new(a);
 366                 perf_header__add_attr(header, h_attr);
 367         }
 368
 369         return h_attr;
 370 }
 371
 372 static void create_counter(int counter, int cpu, pid_t pid)
 373 {
 374         char *filter = filters[counter];
 375         struct perf_event_attr *attr = attrs + counter;
 376         struct perf_header_attr *h_attr;
 377         int track = !counter; /* only the first counter needs these */
 378         int ret;
 379         struct {
 380                 u64 count;
 381                 u64 time_enabled;
 382                 u64 time_running;
 383                 u64 id;
 384         } read_data;
 385
 386         attr->read_format       = PERF_FORMAT_TOTAL_TIME_ENABLED |
 387                                   PERF_FORMAT_TOTAL_TIME_RUNNING |
 388                                   PERF_FORMAT_ID;
 389
 390         attr->sample_type       |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 391
 392         if (freq) {
 393                 attr->sample_type       |= PERF_SAMPLE_PERIOD;
 394                 attr->freq              = 1;
 395                 attr->sample_freq       = freq;
 396         }
 397
 398         if (no_samples)
 399                 attr->sample_freq = 0;
 400
 401         if (inherit_stat)
 402                 attr->inherit_stat = 1;
 403
 404         if (sample_address)
 405                 attr->sample_type       |= PERF_SAMPLE_ADDR;
 406
 407         if (call_graph)
 408                 attr->sample_type       |= PERF_SAMPLE_CALLCHAIN;
 409
 410         if (raw_samples) {
 411                 attr->sample_type       |= PERF_SAMPLE_TIME;
 412                 attr->sample_type       |= PERF_SAMPLE_RAW;
 413                 attr->sample_type       |= PERF_SAMPLE_CPU;
 414         }
 415
 416         attr->mmap              = track;
 417         attr->comm              = track;
 418         attr->inherit           = (cpu < 0) && inherit;
 419         attr->disabled          = 1;
 420
 421 try_again:
 422         fd[nr_cpu][counter] = sys_perf_event_open(attr, pid, cpu, group_fd, 0);
 423
 424         if (fd[nr_cpu][counter] < 0) {
 425                 int err = errno;
 426
 427                 if (err == EPERM)
 428                         die("Permission error - are you root?\n");
 429                 else if (err ==  ENODEV && profile_cpu != -1)
 430                         die("No such device - did you specify an out-of-range profile CPU?\n");
 431
 432                 /*
 433                  * If it's cycles then fall back to hrtimer
 434                  * based cpu-clock-tick sw counter, which
 435                  * is always available even if no PMU support:
 436                  */
 437                 if (attr->type == PERF_TYPE_HARDWARE
 438                         && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
 439
 440                         if (verbose)
 441                                 warning(" ... trying to fall back to cpu-clock-ticks\n");
 442                         attr->type = PERF_TYPE_SOFTWARE;
 443                         attr->config = PERF_COUNT_SW_CPU_CLOCK;
 444                         goto try_again;
 445                 }
 446                 printf("\n");
 447                 error("perfcounter syscall returned with %d (%s)\n",
 448                         fd[nr_cpu][counter], strerror(err));
 449                 die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
 450                 exit(-1);
 451         }
 452
 453         h_attr = get_header_attr(attr, counter);
 454
 455         if (!file_new) {
 456                 if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
 457                         fprintf(stderr, "incompatible append\n");
 458                         exit(-1);
 459                 }
 460         }
 461
 462         if (read(fd[nr_cpu][counter], &read_data, sizeof(read_data)) == -1) {
 463                 perror("Unable to read perf file descriptor\n");
 464                 exit(-1);
 465         }
 466
 467         perf_header_attr__add_id(h_attr, read_data.id);
 468
 469         assert(fd[nr_cpu][counter] >= 0);
 470         fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
 471
 472         /*
 473          * First counter acts as the group leader:
 474          */
 475         if (group && group_fd == -1)
 476                 group_fd = fd[nr_cpu][counter];
 477         if (multiplex && multiplex_fd == -1)
 478                 multiplex_fd = fd[nr_cpu][counter];
 479
 480         if (multiplex && fd[nr_cpu][counter] != multiplex_fd) {
 481
 482                 ret = ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
 483                 assert(ret != -1);
 484         } else {
 485                 event_array[nr_poll].fd = fd[nr_cpu][counter];
 486                 event_array[nr_poll].events = POLLIN;
 487                 nr_poll++;
 488
 489                 mmap_array[nr_cpu][counter].counter = counter;
 490                 mmap_array[nr_cpu][counter].prev = 0;
 491                 mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
 492                 mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
 493                                 PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter], 0);
 494                 if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
 495                         error("failed to mmap with %d (%s)\n", errno, strerror(errno));
 496                         exit(-1);
 497                 }
 498         }
 499
 500         if (filter != NULL) {
 501                 ret = ioctl(fd[nr_cpu][counter],
 502                             PERF_EVENT_IOC_SET_FILTER, filter);
 503                 if (ret) {
 504                         error("failed to set filter with %d (%s)\n", errno,
 505                               strerror(errno));
 506                         exit(-1);
 507                 }
 508         }
 509
 510         ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_ENABLE);
 511 }
 512
 513 static void open_counters(int cpu, pid_t pid)
 514 {
 515         int counter;
 516
 517         group_fd = -1;
 518         for (counter = 0; counter < nr_counters; counter++)
 519                 create_counter(counter, cpu, pid);
 520
 521         nr_cpu++;
 522 }
 523
 524 static void atexit_header(void)
 525 {
 526         header->data_size += bytes_written;
 527
 528         perf_header__write(header, output);
 529 }
 530
 531 static int __cmd_record(int argc, const char **argv)
 532 {
 533         int i, counter;
 534         struct stat st;
 535         pid_t pid = 0;
 536         int flags;
 537         int ret;
 538         unsigned long waking = 0;
 539
 540         page_size = sysconf(_SC_PAGE_SIZE);
 541         nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
 542         assert(nr_cpus <= MAX_NR_CPUS);
 543         assert(nr_cpus >= 0);
 544
 545         atexit(sig_atexit);
 546         signal(SIGCHLD, sig_handler);
 547         signal(SIGINT, sig_handler);
 548
 549         if (!stat(output_name, &st) && st.st_size) {
 550                 if (!force && !append_file) {
 551                         fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
 552                                         output_name);
 553                         exit(-1);
 554                 }
 555         } else {
 556                 append_file = 0;
 557         }
 558
 559         flags = O_CREAT|O_RDWR;
 560         if (append_file)
 561                 file_new = 0;
 562         else
 563                 flags |= O_TRUNC;
 564
 565         output = open(output_name, flags, S_IRUSR|S_IWUSR);
 566         if (output < 0) {
 567                 perror("failed to create output file");
 568                 exit(-1);
 569         }
 570
 571         if (!file_new)
 572                 header = perf_header__read(output);
 573         else
 574                 header = perf_header__new();
 575
 576         if (raw_samples) {
 577                 perf_header__feat_trace_info(header);
 578         } else {
 579                 for (i = 0; i < nr_counters; i++) {
 580                         if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
 581                                 perf_header__feat_trace_info(header);
 582                                 break;
 583                         }
 584                 }
 585         }
 586
 587         atexit(atexit_header);
 588
 589         if (!system_wide) {
 590                 pid = target_pid;
 591                 if (pid == -1)
 592                         pid = getpid();
 593
 594                 open_counters(profile_cpu, pid);
 595         } else {
 596                 if (profile_cpu != -1) {
 597                         open_counters(profile_cpu, target_pid);
 598                 } else {
 599                         for (i = 0; i < nr_cpus; i++)
 600                                 open_counters(i, target_pid);
 601                 }
 602         }
 603
 604         if (file_new)
 605                 perf_header__write(header, output);
 606
 607         if (!system_wide) {
 608                 pid_t tgid = pid_synthesize_comm_event(pid, 0);
 609                 pid_synthesize_mmap_samples(pid, tgid);
 610         } else
 611                 synthesize_all();
 612
 613         if (target_pid == -1 && argc) {
 614                 pid = fork();
 615                 if (pid < 0)
 616                         perror("failed to fork");
 617
 618                 if (!pid) {
 619                         if (execvp(argv[0], (char **)argv)) {
 620                                 perror(argv[0]);
 621                                 exit(-1);
 622                         }
 623                 }
 624
 625                 child_pid = pid;
 626         }
 627
 628         if (realtime_prio) {
 629                 struct sched_param param;
 630
 631                 param.sched_priority = realtime_prio;
 632                 if (sched_setscheduler(0, SCHED_FIFO, &param)) {
 633                         pr_err("Could not set realtime priority.\n");
 634                         exit(-1);
 635                 }
 636         }
 637
 638         for (;;) {
 639                 int hits = samples;
 640
 641                 for (i = 0; i < nr_cpu; i++) {
 642                         for (counter = 0; counter < nr_counters; counter++) {
 643                                 if (mmap_array[i][counter].base)
 644                                         mmap_read(&mmap_array[i][counter]);
 645                         }
 646                 }
 647
 648                 if (hits == samples) {
 649                         if (done)
 650                                 break;
 651                         ret = poll(event_array, nr_poll, -1);
 652                         waking++;
 653                 }
 654
 655                 if (done) {
 656                         for (i = 0; i < nr_cpu; i++) {
 657                                 for (counter = 0; counter < nr_counters; counter++)
 658                                         ioctl(fd[i][counter], PERF_EVENT_IOC_DISABLE);
 659                         }
 660                 }
 661         }
 662
 663         fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
 664
 665         /*
 666          * Approximate RIP event size: 24 bytes.
 667          */
 668         fprintf(stderr,
 669                 "[ perf record: Captured and wrote %.3f MB %s (~%lld samples) ]\n",
 670                 (double)bytes_written / 1024.0 / 1024.0,
 671                 output_name,
 672                 bytes_written / 24);
 673
 674         return 0;
 675 }
 676
 677 static const char * const record_usage[] = {
 678         "perf record [<options>] [<command>]",
 679         "perf record [<options>] -- <command> [<options>]",
 680         NULL
 681 };
 682
 683 static const struct option options[] = {
 684         OPT_CALLBACK('e', "event", NULL, "event",
 685                      "event selector. use 'perf list' to list available events",
 686                      parse_events),
 687         OPT_CALLBACK(0, "filter", NULL, "filter",
 688                      "event filter", parse_filter),
 689         OPT_INTEGER('p', "pid", &target_pid,
 690                     "record events on existing pid"),
 691         OPT_INTEGER('r', "realtime", &realtime_prio,
 692                     "collect data with this RT SCHED_FIFO priority"),
 693         OPT_BOOLEAN('R', "raw-samples", &raw_samples,
 694                     "collect raw sample records from all opened counters"),
 695         OPT_BOOLEAN('a', "all-cpus", &system_wide,
 696                             "system-wide collection from all CPUs"),
 697         OPT_BOOLEAN('A', "append", &append_file,
 698                             "append to the output file to do incremental profiling"),
 699         OPT_INTEGER('C', "profile_cpu", &profile_cpu,
 700                             "CPU to profile on"),
 701         OPT_BOOLEAN('f', "force", &force,
 702                         "overwrite existing data file"),
 703         OPT_LONG('c', "count", &default_interval,
 704                     "event period to sample"),
 705         OPT_STRING('o', "output", &output_name, "file",
 706                     "output file name"),
 707         OPT_BOOLEAN('i', "inherit", &inherit,
 708                     "child tasks inherit counters"),
 709         OPT_INTEGER('F', "freq", &freq,
 710                     "profile at this frequency"),
 711         OPT_INTEGER('m', "mmap-pages", &mmap_pages,
 712                     "number of mmap data pages"),
 713         OPT_BOOLEAN('g', "call-graph", &call_graph,
 714                     "do call-graph (stack chain/backtrace) recording"),
 715         OPT_BOOLEAN('v', "verbose", &verbose,
 716                     "be more verbose (show counter open errors, etc)"),
 717         OPT_BOOLEAN('s', "stat", &inherit_stat,
 718                     "per thread counts"),
 719         OPT_BOOLEAN('d', "data", &sample_address,
 720                     "Sample addresses"),
 721         OPT_BOOLEAN('n', "no-samples", &no_samples,
 722                     "don't sample"),
 723         OPT_BOOLEAN('M', "multiplex", &multiplex,
 724                     "multiplex counter output in a single channel"),
 725         OPT_END()
 726 };
 727
 728 int cmd_record(int argc, const char **argv, const char *prefix __used)
 729 {
 730         int counter;
 731
 732         argc = parse_options(argc, argv, options, record_usage,
 733                 PARSE_OPT_STOP_AT_NON_OPTION);
 734         if (!argc && target_pid == -1 && !system_wide)
 735                 usage_with_options(record_usage, options);
 736
 737         if (!nr_counters) {
 738                 nr_counters     = 1;
 739                 attrs[0].type   = PERF_TYPE_HARDWARE;
 740                 attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
 741         }
 742
 743         /*
 744          * User specified count overrides default frequency.
 745          */
 746         if (default_interval)
 747                 freq = 0;
 748         else if (freq) {
 749                 default_interval = freq;
 750         } else {
 751                 fprintf(stderr, "frequency and count are zero, aborting\n");
 752                 exit(EXIT_FAILURE);
 753         }
 754
 755         for (counter = 0; counter < nr_counters; counter++) {
 756                 if (attrs[counter].sample_period)
 757                         continue;
 758
 759                 attrs[counter].sample_period = default_interval;
 760         }
 761
 762         return __cmd_record(argc, argv);
 763 }