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 #include "util/session.h"
  21 #include "util/symbol.h"
  22
  23 #include <unistd.h>
  24 #include <sched.h>
  25
  26 static int                      fd[MAX_NR_CPUS][MAX_COUNTERS];
  27
  28 static long                     default_interval                =      0;
  29
  30 static int                      nr_cpus                         =      0;
  31 static unsigned int             page_size;
  32 static unsigned int             mmap_pages                      =    128;
  33 static int                      freq                            =   1000;
  34 static int                      output;
  35 static const char               *output_name                    = "perf.data";
  36 static int                      group                           =      0;
  37 static unsigned int             realtime_prio                   =      0;
  38 static int                      raw_samples                     =      0;
  39 static int                      system_wide                     =      0;
  40 static int                      profile_cpu                     =     -1;
  41 static pid_t                    target_pid                      =     -1;
  42 static pid_t                    child_pid                       =     -1;
  43 static int                      inherit                         =      1;
  44 static int                      force                           =      0;
  45 static int                      append_file                     =      0;
  46 static int                      call_graph                      =      0;
  47 static int                      inherit_stat                    =      0;
  48 static int                      no_samples                      =      0;
  49 static int                      sample_address                  =      0;
  50 static int                      multiplex                       =      0;
  51 static int                      multiplex_fd                    =     -1;
  52
  53 static long                     samples                         =      0;
  54 static struct timeval           last_read;
  55 static struct timeval           this_read;
  56
  57 static u64                      bytes_written                   =      0;
  58
  59 static struct pollfd            event_array[MAX_NR_CPUS * MAX_COUNTERS];
  60
  61 static int                      nr_poll                         =      0;
  62 static int                      nr_cpu                          =      0;
  63
  64 static int                      file_new                        =      1;
  65
  66 static struct perf_session      *session;
  67
  68 struct mmap_data {
  69         int                     counter;
  70         void                    *base;
  71         unsigned int            mask;
  72         unsigned int            prev;
  73 };
  74
  75 static struct mmap_data         mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
  76
  77 static unsigned long mmap_read_head(struct mmap_data *md)
  78 {
  79         struct perf_event_mmap_page *pc = md->base;
  80         long head;
  81
  82         head = pc->data_head;
  83         rmb();
  84
  85         return head;
  86 }
  87
  88 static void mmap_write_tail(struct mmap_data *md, unsigned long tail)
  89 {
  90         struct perf_event_mmap_page *pc = md->base;
  91
  92         /*
  93          * ensure all reads are done before we write the tail out.
  94          */
  95         /* mb(); */
  96         pc->data_tail = tail;
  97 }
  98
  99 static void write_output(void *buf, size_t size)
 100 {
 101         while (size) {
 102                 int ret = write(output, buf, size);
 103
 104                 if (ret < 0)
 105                         die("failed to write");
 106
 107                 size -= ret;
 108                 buf += ret;
 109
 110                 bytes_written += ret;
 111         }
 112 }
 113
 114 static void write_event(event_t *buf, size_t size)
 115 {
 116         /*
 117         * Add it to the list of DSOs, so that when we finish this
 118          * record session we can pick the available build-ids.
 119          */
 120         if (buf->header.type == PERF_RECORD_MMAP) {
 121                 struct list_head *head = &dsos__user;
 122                 if (buf->mmap.header.misc == 1)
 123                         head = &dsos__kernel;
 124                 __dsos__findnew(head, buf->mmap.filename);
 125         }
 126
 127         write_output(buf, size);
 128 }
 129
 130 static int process_synthesized_event(event_t *event,
 131                                      struct perf_session *self __used)
 132 {
 133         write_event(event, event->header.size);
 134         return 0;
 135 }
 136
 137 static void mmap_read(struct mmap_data *md)
 138 {
 139         unsigned int head = mmap_read_head(md);
 140         unsigned int old = md->prev;
 141         unsigned char *data = md->base + page_size;
 142         unsigned long size;
 143         void *buf;
 144         int diff;
 145
 146         gettimeofday(&this_read, NULL);
 147
 148         /*
 149          * If we're further behind than half the buffer, there's a chance
 150          * the writer will bite our tail and mess up the samples under us.
 151          *
 152          * If we somehow ended up ahead of the head, we got messed up.
 153          *
 154          * In either case, truncate and restart at head.
 155          */
 156         diff = head - old;
 157         if (diff < 0) {
 158                 struct timeval iv;
 159                 unsigned long msecs;
 160
 161                 timersub(&this_read, &last_read, &iv);
 162                 msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
 163
 164                 fprintf(stderr, "WARNING: failed to keep up with mmap data."
 165                                 "  Last read %lu msecs ago.\n", msecs);
 166
 167                 /*
 168                  * head points to a known good entry, start there.
 169                  */
 170                 old = head;
 171         }
 172
 173         last_read = this_read;
 174
 175         if (old != head)
 176                 samples++;
 177
 178         size = head - old;
 179
 180         if ((old & md->mask) + size != (head & md->mask)) {
 181                 buf = &data[old & md->mask];
 182                 size = md->mask + 1 - (old & md->mask);
 183                 old += size;
 184
 185                 write_event(buf, size);
 186         }
 187
 188         buf = &data[old & md->mask];
 189         size = head - old;
 190         old += size;
 191
 192         write_event(buf, size);
 193
 194         md->prev = old;
 195         mmap_write_tail(md, old);
 196 }
 197
 198 static volatile int done = 0;
 199 static volatile int signr = -1;
 200
 201 static void sig_handler(int sig)
 202 {
 203         done = 1;
 204         signr = sig;
 205 }
 206
 207 static void sig_atexit(void)
 208 {
 209         if (child_pid != -1)
 210                 kill(child_pid, SIGTERM);
 211
 212         if (signr == -1)
 213                 return;
 214
 215         signal(signr, SIG_DFL);
 216         kill(getpid(), signr);
 217 }
 218
 219 static int group_fd;
 220
 221 static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int nr)
 222 {
 223         struct perf_header_attr *h_attr;
 224
 225         if (nr < session->header.attrs) {
 226                 h_attr = session->header.attr[nr];
 227         } else {
 228                 h_attr = perf_header_attr__new(a);
 229                 if (h_attr != NULL)
 230                         if (perf_header__add_attr(&session->header, h_attr) < 0) {
 231                                 perf_header_attr__delete(h_attr);
 232                                 h_attr = NULL;
 233                         }
 234         }
 235
 236         return h_attr;
 237 }
 238
 239 static void create_counter(int counter, int cpu, pid_t pid)
 240 {
 241         char *filter = filters[counter];
 242         struct perf_event_attr *attr = attrs + counter;
 243         struct perf_header_attr *h_attr;
 244         int track = !counter; /* only the first counter needs these */
 245         int ret;
 246         struct {
 247                 u64 count;
 248                 u64 time_enabled;
 249                 u64 time_running;
 250                 u64 id;
 251         } read_data;
 252
 253         attr->read_format       = PERF_FORMAT_TOTAL_TIME_ENABLED |
 254                                   PERF_FORMAT_TOTAL_TIME_RUNNING |
 255                                   PERF_FORMAT_ID;
 256
 257         attr->sample_type       |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
 258
 259         if (freq) {
 260                 attr->sample_type       |= PERF_SAMPLE_PERIOD;
 261                 attr->freq              = 1;
 262                 attr->sample_freq       = freq;
 263         }
 264
 265         if (no_samples)
 266                 attr->sample_freq = 0;
 267
 268         if (inherit_stat)
 269                 attr->inherit_stat = 1;
 270
 271         if (sample_address)
 272                 attr->sample_type       |= PERF_SAMPLE_ADDR;
 273
 274         if (call_graph)
 275                 attr->sample_type       |= PERF_SAMPLE_CALLCHAIN;
 276
 277         if (raw_samples) {
 278                 attr->sample_type       |= PERF_SAMPLE_TIME;
 279                 attr->sample_type       |= PERF_SAMPLE_RAW;
 280                 attr->sample_type       |= PERF_SAMPLE_CPU;
 281         }
 282
 283         attr->mmap              = track;
 284         attr->comm              = track;
 285         attr->inherit           = inherit;
 286         attr->disabled          = 1;
 287
 288 try_again:
 289         fd[nr_cpu][counter] = sys_perf_event_open(attr, pid, cpu, group_fd, 0);
 290
 291         if (fd[nr_cpu][counter] < 0) {
 292                 int err = errno;
 293
 294                 if (err == EPERM || err == EACCES)
 295                         die("Permission error - are you root?\n");
 296                 else if (err ==  ENODEV && profile_cpu != -1)
 297                         die("No such device - did you specify an out-of-range profile CPU?\n");
 298
 299                 /*
 300                  * If it's cycles then fall back to hrtimer
 301                  * based cpu-clock-tick sw counter, which
 302                  * is always available even if no PMU support:
 303                  */
 304                 if (attr->type == PERF_TYPE_HARDWARE
 305                         && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
 306
 307                         if (verbose)
 308                                 warning(" ... trying to fall back to cpu-clock-ticks\n");
 309                         attr->type = PERF_TYPE_SOFTWARE;
 310                         attr->config = PERF_COUNT_SW_CPU_CLOCK;
 311                         goto try_again;
 312                 }
 313                 printf("\n");
 314                 error("perfcounter syscall returned with %d (%s)\n",
 315                         fd[nr_cpu][counter], strerror(err));
 316
 317 #if defined(__i386__) || defined(__x86_64__)
 318                 if (attr->type == PERF_TYPE_HARDWARE && err == EOPNOTSUPP)
 319                         die("No hardware sampling interrupt available. No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.\n");
 320 #endif
 321
 322                 die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
 323                 exit(-1);
 324         }
 325
 326         h_attr = get_header_attr(attr, counter);
 327         if (h_attr == NULL)
 328                 die("nomem\n");
 329
 330         if (!file_new) {
 331                 if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
 332                         fprintf(stderr, "incompatible append\n");
 333                         exit(-1);
 334                 }
 335         }
 336
 337         if (read(fd[nr_cpu][counter], &read_data, sizeof(read_data)) == -1) {
 338                 perror("Unable to read perf file descriptor\n");
 339                 exit(-1);
 340         }
 341
 342         if (perf_header_attr__add_id(h_attr, read_data.id) < 0) {
 343                 pr_warning("Not enough memory to add id\n");
 344                 exit(-1);
 345         }
 346
 347         assert(fd[nr_cpu][counter] >= 0);
 348         fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
 349
 350         /*
 351          * First counter acts as the group leader:
 352          */
 353         if (group && group_fd == -1)
 354                 group_fd = fd[nr_cpu][counter];
 355         if (multiplex && multiplex_fd == -1)
 356                 multiplex_fd = fd[nr_cpu][counter];
 357
 358         if (multiplex && fd[nr_cpu][counter] != multiplex_fd) {
 359
 360                 ret = ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
 361                 assert(ret != -1);
 362         } else {
 363                 event_array[nr_poll].fd = fd[nr_cpu][counter];
 364                 event_array[nr_poll].events = POLLIN;
 365                 nr_poll++;
 366
 367                 mmap_array[nr_cpu][counter].counter = counter;
 368                 mmap_array[nr_cpu][counter].prev = 0;
 369                 mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
 370                 mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
 371                                 PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter], 0);
 372                 if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
 373                         error("failed to mmap with %d (%s)\n", errno, strerror(errno));
 374                         exit(-1);
 375                 }
 376         }
 377
 378         if (filter != NULL) {
 379                 ret = ioctl(fd[nr_cpu][counter],
 380                             PERF_EVENT_IOC_SET_FILTER, filter);
 381                 if (ret) {
 382                         error("failed to set filter with %d (%s)\n", errno,
 383                               strerror(errno));
 384                         exit(-1);
 385                 }
 386         }
 387
 388         ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_ENABLE);
 389 }
 390
 391 static void open_counters(int cpu, pid_t pid)
 392 {
 393         int counter;
 394
 395         group_fd = -1;
 396         for (counter = 0; counter < nr_counters; counter++)
 397                 create_counter(counter, cpu, pid);
 398
 399         nr_cpu++;
 400 }
 401
 402 static void atexit_header(void)
 403 {
 404         session->header.data_size += bytes_written;
 405
 406         perf_header__write(&session->header, output, true);
 407 }
 408
 409 static int __cmd_record(int argc, const char **argv)
 410 {
 411         int i, counter;
 412         struct stat st;
 413         pid_t pid = 0;
 414         int flags;
 415         int err;
 416         unsigned long waking = 0;
 417         int child_ready_pipe[2], go_pipe[2];
 418         const bool forks = target_pid == -1 && argc > 0;
 419         char buf;
 420
 421         page_size = sysconf(_SC_PAGE_SIZE);
 422         nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
 423         assert(nr_cpus <= MAX_NR_CPUS);
 424         assert(nr_cpus >= 0);
 425
 426         atexit(sig_atexit);
 427         signal(SIGCHLD, sig_handler);
 428         signal(SIGINT, sig_handler);
 429
 430         if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) {
 431                 perror("failed to create pipes");
 432                 exit(-1);
 433         }
 434
 435         if (!stat(output_name, &st) && st.st_size) {
 436                 if (!force) {
 437                         if (!append_file) {
 438                                 pr_err("Error, output file %s exists, use -A "
 439                                        "to append or -f to overwrite.\n",
 440                                        output_name);
 441                                 exit(-1);
 442                         }
 443                 } else {
 444                         char oldname[PATH_MAX];
 445                         snprintf(oldname, sizeof(oldname), "%s.old",
 446                                  output_name);
 447                         unlink(oldname);
 448                         rename(output_name, oldname);
 449                 }
 450         } else {
 451                 append_file = 0;
 452         }
 453
 454         flags = O_CREAT|O_RDWR;
 455         if (append_file)
 456                 file_new = 0;
 457         else
 458                 flags |= O_TRUNC;
 459
 460         output = open(output_name, flags, S_IRUSR|S_IWUSR);
 461         if (output < 0) {
 462                 perror("failed to create output file");
 463                 exit(-1);
 464         }
 465
 466         session = perf_session__new(output_name, O_WRONLY, force);
 467         if (session == NULL) {
 468                 pr_err("Not enough memory for reading perf file header\n");
 469                 return -1;
 470         }
 471
 472         if (!file_new) {
 473                 err = perf_header__read(&session->header, output);
 474                 if (err < 0)
 475                         return err;
 476         }
 477
 478         if (raw_samples) {
 479                 perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
 480         } else {
 481                 for (i = 0; i < nr_counters; i++) {
 482                         if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
 483                                 perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
 484                                 break;
 485                         }
 486                 }
 487         }
 488
 489         atexit(atexit_header);
 490
 491         if (forks) {
 492                 pid = fork();
 493                 if (pid < 0) {
 494                         perror("failed to fork");
 495                         exit(-1);
 496                 }
 497
 498                 if (!pid) {
 499                         close(child_ready_pipe[0]);
 500                         close(go_pipe[1]);
 501                         fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
 502
 503                         /*
 504                          * Do a dummy execvp to get the PLT entry resolved,
 505                          * so we avoid the resolver overhead on the real
 506                          * execvp call.
 507                          */
 508                         execvp("", (char **)argv);
 509
 510                         /*
 511                          * Tell the parent we're ready to go
 512                          */
 513                         close(child_ready_pipe[1]);
 514
 515                         /*
 516                          * Wait until the parent tells us to go.
 517                          */
 518                         if (read(go_pipe[0], &buf, 1) == -1)
 519                                 perror("unable to read pipe");
 520
 521                         execvp(argv[0], (char **)argv);
 522
 523                         perror(argv[0]);
 524                         exit(-1);
 525                 }
 526
 527                 child_pid = pid;
 528
 529                 if (!system_wide)
 530                         target_pid = pid;
 531
 532                 close(child_ready_pipe[1]);
 533                 close(go_pipe[0]);
 534                 /*
 535                  * wait for child to settle
 536                  */
 537                 if (read(child_ready_pipe[0], &buf, 1) == -1) {
 538                         perror("unable to read pipe");
 539                         exit(-1);
 540                 }
 541                 close(child_ready_pipe[0]);
 542         }
 543
 544
 545         if ((!system_wide && !inherit) || profile_cpu != -1) {
 546                 open_counters(profile_cpu, target_pid);
 547         } else {
 548                 for (i = 0; i < nr_cpus; i++)
 549                         open_counters(i, target_pid);
 550         }
 551
 552         if (file_new) {
 553                 err = perf_header__write(&session->header, output, false);
 554                 if (err < 0)
 555                         return err;
 556         }
 557
 558         err = event__synthesize_kernel_mmap(process_synthesized_event,
 559                                             session, "_text");
 560         if (err < 0) {
 561                 pr_err("Couldn't record kernel reference relocation symbol.\n");
 562                 return err;
 563         }
 564
 565         err = event__synthesize_modules(process_synthesized_event, session);
 566         if (err < 0) {
 567                 pr_err("Couldn't record kernel reference relocation symbol.\n");
 568                 return err;
 569         }
 570
 571         if (!system_wide && profile_cpu == -1)
 572                 event__synthesize_thread(pid, process_synthesized_event,
 573                                          session);
 574         else
 575                 event__synthesize_threads(process_synthesized_event, session);
 576
 577         if (realtime_prio) {
 578                 struct sched_param param;
 579
 580                 param.sched_priority = realtime_prio;
 581                 if (sched_setscheduler(0, SCHED_FIFO, &param)) {
 582                         pr_err("Could not set realtime priority.\n");
 583                         exit(-1);
 584                 }
 585         }
 586
 587         /*
 588          * Let the child rip
 589          */
 590         if (forks)
 591                 close(go_pipe[1]);
 592
 593         for (;;) {
 594                 int hits = samples;
 595
 596                 for (i = 0; i < nr_cpu; i++) {
 597                         for (counter = 0; counter < nr_counters; counter++) {
 598                                 if (mmap_array[i][counter].base)
 599                                         mmap_read(&mmap_array[i][counter]);
 600                         }
 601                 }
 602
 603                 if (hits == samples) {
 604                         if (done)
 605                                 break;
 606                         err = poll(event_array, nr_poll, -1);
 607                         waking++;
 608                 }
 609
 610                 if (done) {
 611                         for (i = 0; i < nr_cpu; i++) {
 612                                 for (counter = 0; counter < nr_counters; counter++)
 613                                         ioctl(fd[i][counter], PERF_EVENT_IOC_DISABLE);
 614                         }
 615                 }
 616         }
 617
 618         fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
 619
 620         /*
 621          * Approximate RIP event size: 24 bytes.
 622          */
 623         fprintf(stderr,
 624                 "[ perf record: Captured and wrote %.3f MB %s (~%lld samples) ]\n",
 625                 (double)bytes_written / 1024.0 / 1024.0,
 626                 output_name,
 627                 bytes_written / 24);
 628
 629         return 0;
 630 }
 631
 632 static const char * const record_usage[] = {
 633         "perf record [<options>] [<command>]",
 634         "perf record [<options>] -- <command> [<options>]",
 635         NULL
 636 };
 637
 638 static const struct option options[] = {
 639         OPT_CALLBACK('e', "event", NULL, "event",
 640                      "event selector. use 'perf list' to list available events",
 641                      parse_events),
 642         OPT_CALLBACK(0, "filter", NULL, "filter",
 643                      "event filter", parse_filter),
 644         OPT_INTEGER('p', "pid", &target_pid,
 645                     "record events on existing pid"),
 646         OPT_INTEGER('r', "realtime", &realtime_prio,
 647                     "collect data with this RT SCHED_FIFO priority"),
 648         OPT_BOOLEAN('R', "raw-samples", &raw_samples,
 649                     "collect raw sample records from all opened counters"),
 650         OPT_BOOLEAN('a', "all-cpus", &system_wide,
 651                             "system-wide collection from all CPUs"),
 652         OPT_BOOLEAN('A', "append", &append_file,
 653                             "append to the output file to do incremental profiling"),
 654         OPT_INTEGER('C', "profile_cpu", &profile_cpu,
 655                             "CPU to profile on"),
 656         OPT_BOOLEAN('f', "force", &force,
 657                         "overwrite existing data file"),
 658         OPT_LONG('c', "count", &default_interval,
 659                     "event period to sample"),
 660         OPT_STRING('o', "output", &output_name, "file",
 661                     "output file name"),
 662         OPT_BOOLEAN('i', "inherit", &inherit,
 663                     "child tasks inherit counters"),
 664         OPT_INTEGER('F', "freq", &freq,
 665                     "profile at this frequency"),
 666         OPT_INTEGER('m', "mmap-pages", &mmap_pages,
 667                     "number of mmap data pages"),
 668         OPT_BOOLEAN('g', "call-graph", &call_graph,
 669                     "do call-graph (stack chain/backtrace) recording"),
 670         OPT_BOOLEAN('v', "verbose", &verbose,
 671                     "be more verbose (show counter open errors, etc)"),
 672         OPT_BOOLEAN('s', "stat", &inherit_stat,
 673                     "per thread counts"),
 674         OPT_BOOLEAN('d', "data", &sample_address,
 675                     "Sample addresses"),
 676         OPT_BOOLEAN('n', "no-samples", &no_samples,
 677                     "don't sample"),
 678         OPT_BOOLEAN('M', "multiplex", &multiplex,
 679                     "multiplex counter output in a single channel"),
 680         OPT_END()
 681 };
 682
 683 int cmd_record(int argc, const char **argv, const char *prefix __used)
 684 {
 685         int counter;
 686
 687         argc = parse_options(argc, argv, options, record_usage,
 688                             PARSE_OPT_STOP_AT_NON_OPTION);
 689         if (!argc && target_pid == -1 && !system_wide && profile_cpu == -1)
 690                 usage_with_options(record_usage, options);
 691
 692         symbol__init();
 693
 694         if (!nr_counters) {
 695                 nr_counters     = 1;
 696                 attrs[0].type   = PERF_TYPE_HARDWARE;
 697                 attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
 698         }
 699
 700         /*
 701          * User specified count overrides default frequency.
 702          */
 703         if (default_interval)
 704                 freq = 0;
 705         else if (freq) {
 706                 default_interval = freq;
 707         } else {
 708                 fprintf(stderr, "frequency and count are zero, aborting\n");
 709                 exit(EXIT_FAILURE);
 710         }
 711
 712         for (counter = 0; counter < nr_counters; counter++) {
 713                 if (attrs[counter].sample_period)
 714                         continue;
 715
 716                 attrs[counter].sample_period = default_interval;
 717         }
 718
 719         return __cmd_record(argc, argv);
 720 }