blktrace.c

   1 /*
   2  * block queue tracing application
   3  *
   4  * Copyright (C) 2005 Jens Axboe <axboe@suse.de>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21 #include <pthread.h>
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <unistd.h>
  25 #include <locale.h>
  26 #include <signal.h>
  27 #include <fcntl.h>
  28 #include <string.h>
  29 #include <sys/ioctl.h>
  30 #include <sys/param.h>
  31 #include <sys/statfs.h>
  32 #include <sys/poll.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <sched.h>
  36 #include <ctype.h>
  37 #include <getopt.h>
  38 #include <errno.h>
  39 #include <assert.h>
  40
  41 #include "blktrace.h"
  42 #include "list.h"
  43
  44 static char blktrace_version[] = "0.99";
  45
  46 /*
  47  * You may want to increase this even more, if you are logging at a high
  48  * rate and see skipped/missed events
  49  */
  50 #define BUF_SIZE        (512 * 1024)
  51 #define BUF_NR          (4)
  52
  53 #define OFILE_BUF       (128 * 1024)
  54
  55 #define RELAYFS_TYPE    0xF0B4A981
  56
  57 #define RING_INIT_NR    (2)
  58 #define RING_MAX_NR     (16UL)
  59
  60 #define S_OPTS  "d:a:A:r:o:kw:Vb:n:D:"
  61 static struct option l_opts[] = {
  62         {
  63                 .name = "dev",
  64                 .has_arg = required_argument,
  65                 .flag = NULL,
  66                 .val = 'd'
  67         },
  68         {
  69                 .name = "act-mask",
  70                 .has_arg = required_argument,
  71                 .flag = NULL,
  72                 .val = 'a'
  73         },
  74         {
  75                 .name = "set-mask",
  76                 .has_arg = required_argument,
  77                 .flag = NULL,
  78                 .val = 'A'
  79         },
  80         {
  81                 .name = "relay",
  82                 .has_arg = required_argument,
  83                 .flag = NULL,
  84                 .val = 'r'
  85         },
  86         {
  87                 .name = "output",
  88                 .has_arg = required_argument,
  89                 .flag = NULL,
  90                 .val = 'o'
  91         },
  92         {
  93                 .name = "kill",
  94                 .has_arg = no_argument,
  95                 .flag = NULL,
  96                 .val = 'k'
  97         },
  98         {
  99                 .name = "stopwatch",
 100                 .has_arg = required_argument,
 101                 .flag = NULL,
 102                 .val = 'w'
 103         },
 104         {
 105                 .name = "version",
 106                 .has_arg = no_argument,
 107                 .flag = NULL,
 108                 .val = 'V'
 109         },
 110         {
 111                 .name = "buffer-size",
 112                 .has_arg = required_argument,
 113                 .flag = NULL,
 114                 .val = 'b'
 115         },
 116         {
 117                 .name = "num-sub-buffers",
 118                 .has_arg = required_argument,
 119                 .flag = NULL,
 120                 .val = 'n'
 121         },
 122         {
 123                 .name = "output-dir",
 124                 .has_arg = required_argument,
 125                 .flag = NULL,
 126                 .val = 'D'
 127         },
 128         {
 129                 .name = NULL,
 130         }
 131 };
 132
 133 struct tip_subbuf {
 134         struct list_head list;
 135         void *buf;
 136         unsigned int len;
 137         unsigned int max_len;
 138 };
 139
 140 struct thread_information {
 141         int cpu;
 142         pthread_t thread;
 143
 144         int fd;
 145         void *fd_buf;
 146         unsigned long fd_off;
 147         unsigned long fd_size;
 148         unsigned long fd_max_size;
 149         char fn[MAXPATHLEN + 64];
 150
 151         FILE *ofile;
 152         char *ofile_buffer;
 153         int ofile_stdout;
 154
 155         unsigned long events_processed;
 156         struct device_information *device;
 157
 158         int exited;
 159
 160         pthread_mutex_t lock;
 161         struct list_head subbuf_list;
 162         struct tip_subbuf *leftover_ts;
 163 };
 164
 165 struct device_information {
 166         int fd;
 167         char *path;
 168         char buts_name[32];
 169         volatile int trace_started;
 170         unsigned long drop_count;
 171         struct thread_information *threads;
 172 };
 173
 174 static int ncpus;
 175 static struct thread_information *thread_information;
 176 static int ndevs;
 177 static struct device_information *device_information;
 178
 179 /* command line option globals */
 180 static char *relay_path;
 181 static char *output_name;
 182 static char *output_dir;
 183 static int act_mask = ~0U;
 184 static int kill_running_trace;
 185 static unsigned long buf_size = BUF_SIZE;
 186 static unsigned long buf_nr = BUF_NR;
 187
 188 #define is_done()       (*(volatile int *)(&done))
 189 static volatile int done;
 190
 191 #define is_trace_stopped()      (*(volatile int *)(&trace_stopped))
 192 static volatile int trace_stopped;
 193
 194 #define is_stat_shown() (*(volatile int *)(&stat_shown))
 195 static volatile int stat_shown;
 196
 197 static void exit_trace(int status);
 198
 199 #define dip_tracing(dip)        (*(volatile int *)(&(dip)->trace_started))
 200 #define dip_set_tracing(dip, v) ((dip)->trace_started = (v))
 201
 202 #define __for_each_dip(__d, __i, __e)   \
 203         for (__i = 0, __d = device_information; __i < __e; __i++, __d++)
 204
 205 #define for_each_dip(__d, __i)  __for_each_dip(__d, __i, ndevs)
 206 #define for_each_tip(__d, __t, __j)     \
 207         for (__j = 0, __t = (__d)->threads; __j < ncpus; __j++, __t++)
 208
 209 static int get_dropped_count(const char *buts_name)
 210 {
 211         int fd;
 212         char tmp[MAXPATHLEN + 64];
 213
 214         snprintf(tmp, sizeof(tmp), "%s/block/%s/dropped",
 215                  relay_path, buts_name);
 216
 217         fd = open(tmp, O_RDONLY);
 218         if (fd < 0) {
 219                 /*
 220                  * this may be ok, if the kernel doesn't support dropped counts
 221                  */
 222                 if (errno == ENOENT)
 223                         return 0;
 224
 225                 fprintf(stderr, "Couldn't open dropped file %s\n", tmp);
 226                 return -1;
 227         }
 228
 229         if (read(fd, tmp, sizeof(tmp)) < 0) {
 230                 perror(tmp);
 231                 close(fd);
 232                 return -1;
 233         }
 234
 235         close(fd);
 236
 237         return atoi(tmp);
 238 }
 239
 240 static int start_trace(struct device_information *dip)
 241 {
 242         struct blk_user_trace_setup buts;
 243
 244         memset(&buts, 0, sizeof(buts));
 245         buts.buf_size = buf_size;
 246         buts.buf_nr = buf_nr;
 247         buts.act_mask = act_mask;
 248
 249         if (ioctl(dip->fd, BLKSTARTTRACE, &buts) < 0) {
 250                 perror("BLKSTARTTRACE");
 251                 return 1;
 252         }
 253
 254         memcpy(dip->buts_name, buts.name, sizeof(dip->buts_name));
 255         dip_set_tracing(dip, 1);
 256         return 0;
 257 }
 258
 259 static void stop_trace(struct device_information *dip)
 260 {
 261         if (dip_tracing(dip) || kill_running_trace) {
 262                 dip_set_tracing(dip, 0);
 263
 264                 if (ioctl(dip->fd, BLKSTOPTRACE) < 0)
 265                         perror("BLKSTOPTRACE");
 266
 267                 close(dip->fd);
 268                 dip->fd = -1;
 269         }
 270 }
 271
 272 static void stop_all_traces(void)
 273 {
 274         struct device_information *dip;
 275         int i;
 276
 277         for_each_dip(dip, i) {
 278                 dip->drop_count = get_dropped_count(dip->buts_name);
 279                 stop_trace(dip);
 280         }
 281 }
 282
 283 static void wait_for_data(struct thread_information *tip)
 284 {
 285         struct pollfd pfd = { .fd = tip->fd, .events = POLLIN };
 286
 287         do {
 288                 poll(&pfd, 1, 100);
 289                 if (pfd.revents & POLLIN)
 290                         break;
 291                 if (tip->ofile_stdout)
 292                         break;
 293         } while (!is_done());
 294 }
 295
 296 static int read_data(struct thread_information *tip, void *buf, int len)
 297 {
 298         int ret = 0;
 299
 300         do {
 301                 wait_for_data(tip);
 302
 303                 ret = read(tip->fd, buf, len);
 304                 if (!ret)
 305                         continue;
 306                 else if (ret > 0)
 307                         return ret;
 308                 else {
 309                         if (errno != EAGAIN) {
 310                                 perror(tip->fn);
 311                                 fprintf(stderr,"Thread %d failed read of %s\n",
 312                                         tip->cpu, tip->fn);
 313                                 break;
 314                         }
 315                         continue;
 316                 }
 317         } while (!is_done());
 318
 319         return ret;
 320 }
 321
 322 static inline void tip_fd_unlock(struct thread_information *tip)
 323 {
 324         pthread_mutex_unlock(&tip->lock);
 325 }
 326
 327 static inline void tip_fd_lock(struct thread_information *tip)
 328 {
 329         pthread_mutex_lock(&tip->lock);
 330 }
 331
 332 static int get_subbuf(struct thread_information *tip)
 333 {
 334         struct tip_subbuf *ts;
 335         int ret;
 336
 337         ts = malloc(sizeof(*ts));
 338         ts->buf = malloc(buf_size);
 339         ts->max_len = buf_size;
 340
 341         ret = read_data(tip, ts->buf, ts->max_len);
 342         if (ret > 0) {
 343                 ts->len = ret;
 344                 tip_fd_lock(tip);
 345                 list_add_tail(&ts->list, &tip->subbuf_list);
 346                 tip_fd_unlock(tip);
 347                 return 0;
 348         }
 349
 350         free(ts->buf);
 351         free(ts);
 352         return -1;
 353 }
 354
 355 static void close_thread(struct thread_information *tip)
 356 {
 357         if (tip->fd != -1)
 358                 close(tip->fd);
 359         if (tip->ofile)
 360                 fclose(tip->ofile);
 361         if (tip->ofile_buffer)
 362                 free(tip->ofile_buffer);
 363         if (tip->fd_buf)
 364                 free(tip->fd_buf);
 365
 366         tip->fd = -1;
 367         tip->ofile = NULL;
 368         tip->ofile_buffer = NULL;
 369         tip->fd_buf = NULL;
 370 }
 371
 372 static void *thread_main(void *arg)
 373 {
 374         struct thread_information *tip = arg;
 375         pid_t pid = getpid();
 376         cpu_set_t cpu_mask;
 377
 378         CPU_ZERO(&cpu_mask);
 379         CPU_SET((tip->cpu), &cpu_mask);
 380
 381         if (sched_setaffinity(pid, sizeof(cpu_mask), &cpu_mask) == -1) {
 382                 perror("sched_setaffinity");
 383                 exit_trace(1);
 384         }
 385
 386         snprintf(tip->fn, sizeof(tip->fn), "%s/block/%s/trace%d",
 387                         relay_path, tip->device->buts_name, tip->cpu);
 388         tip->fd = open(tip->fn, O_RDONLY);
 389         if (tip->fd < 0) {
 390                 perror(tip->fn);
 391                 fprintf(stderr,"Thread %d failed open of %s\n", tip->cpu,
 392                         tip->fn);
 393                 exit_trace(1);
 394         }
 395
 396         for (;;) {
 397                 if (get_subbuf(tip))
 398                         break;
 399         }
 400
 401         tip->exited = 1;
 402         return NULL;
 403 }
 404
 405 static int write_data(struct thread_information *tip,
 406                       void *buf, unsigned int buf_len)
 407 {
 408         int ret;
 409
 410         while (1) {
 411                 ret = fwrite(buf, buf_len, 1, tip->ofile);
 412                 if (ret == 1)
 413                         break;
 414
 415                 if (ret < 0) {
 416                         perror("write");
 417                         return 1;
 418                 }
 419         }
 420
 421         if (tip->ofile_stdout)
 422                 fflush(tip->ofile);
 423
 424         return 0;
 425 }
 426
 427 static int flush_subbuf(struct thread_information *tip, struct tip_subbuf *ts)
 428 {
 429         unsigned int offset = 0;
 430         struct blk_io_trace *t;
 431         int pdu_len, events = 0;
 432
 433         /*
 434          * surplus from last run
 435          */
 436         if (tip->leftover_ts) {
 437                 struct tip_subbuf *prev_ts = tip->leftover_ts;
 438
 439                 if (prev_ts->len + ts->len > prev_ts->max_len) {
 440                         prev_ts->max_len += ts->len;
 441                         prev_ts->buf = realloc(prev_ts->buf, prev_ts->max_len);
 442                 }
 443
 444                 memcpy(prev_ts->buf + prev_ts->len, ts->buf, ts->len);
 445                 prev_ts->len += ts->len;
 446
 447                 free(ts->buf);
 448                 free(ts);
 449
 450                 ts = prev_ts;
 451                 tip->leftover_ts = NULL;
 452         }
 453
 454         while (offset + sizeof(*t) <= ts->len) {
 455                 t = ts->buf + offset;
 456
 457                 if (verify_trace(t))
 458                         return -1;
 459
 460                 pdu_len = t->pdu_len;
 461
 462                 if (offset + sizeof(*t) + pdu_len > ts->len)
 463                         break;
 464
 465                 trace_to_be(t);
 466
 467                 if (write_data(tip, t, sizeof(*t) + pdu_len))
 468                         return -1;
 469
 470                 offset += sizeof(*t) + pdu_len;
 471                 tip->events_processed++;
 472                 events++;
 473         }
 474
 475         /*
 476          * leftover bytes, save them for next time
 477          */
 478         if (offset != ts->len) {
 479                 tip->leftover_ts = ts;
 480                 ts->len -= offset;
 481                 memmove(ts->buf, ts->buf + offset, ts->len);
 482         } else {
 483                 free(ts->buf);
 484                 free(ts);
 485         }
 486
 487         return events;
 488 }
 489
 490 static int write_tip_events(struct thread_information *tip)
 491 {
 492         struct tip_subbuf *ts = NULL;
 493
 494         tip_fd_lock(tip);
 495         if (!list_empty(&tip->subbuf_list)) {
 496                 ts = list_entry(tip->subbuf_list.next, struct tip_subbuf, list);
 497                 list_del(&ts->list);
 498         }
 499         tip_fd_unlock(tip);
 500
 501         if (ts)
 502                 return flush_subbuf(tip, ts);
 503
 504         return 0;
 505 }
 506
 507 /*
 508  * scans the tips we know and writes out the subbuffers we accumulate
 509  */
 510 static void get_and_write_events(void)
 511 {
 512         struct device_information *dip;
 513         struct thread_information *tip;
 514         int i, j, events, ret, tips_running;
 515
 516         while (!is_done()) {
 517                 events = 0;
 518
 519                 for_each_dip(dip, i) {
 520                         for_each_tip(dip, tip, j) {
 521                                 ret = write_tip_events(tip);
 522                                 if (ret > 0)
 523                                         events += ret;
 524                         }
 525                 }
 526
 527                 if (!events)
 528                         usleep(10);
 529         }
 530
 531         /*
 532          * reap stored events
 533          */
 534         do {
 535                 events = 0;
 536                 tips_running = 0;
 537                 for_each_dip(dip, i) {
 538                         for_each_tip(dip, tip, j) {
 539                                 ret = write_tip_events(tip);
 540                                 if (ret > 0)
 541                                         events += ret;
 542                                 tips_running += !tip->exited;
 543                         }
 544                 }
 545                 usleep(10);
 546         } while (events || tips_running);
 547 }
 548
 549 static int start_threads(struct device_information *dip)
 550 {
 551         struct thread_information *tip;
 552         char op[64];
 553         int j, pipeline = output_name && !strcmp(output_name, "-");
 554         int len, mode, vbuf_size;
 555
 556         for_each_tip(dip, tip, j) {
 557                 tip->cpu = j;
 558                 tip->device = dip;
 559                 tip->events_processed = 0;
 560                 INIT_LIST_HEAD(&tip->subbuf_list);
 561                 tip->leftover_ts = NULL;
 562
 563                 if (pipeline) {
 564                         tip->ofile = fdopen(STDOUT_FILENO, "w");
 565                         tip->ofile_stdout = 1;
 566                         mode = _IOLBF;
 567                         vbuf_size = 512;
 568                 } else {
 569                         len = 0;
 570
 571                         if (output_dir)
 572                                 len = sprintf(op, "%s/", output_dir);
 573
 574                         if (output_name) {
 575                                 sprintf(op + len, "%s.blktrace.%d", output_name,
 576                                         tip->cpu);
 577                         } else {
 578                                 sprintf(op + len, "%s.blktrace.%d",
 579                                         dip->buts_name, tip->cpu);
 580                         }
 581                         tip->ofile = fopen(op, "w");
 582                         tip->ofile_stdout = 0;
 583                         mode = _IOFBF;
 584                         vbuf_size = OFILE_BUF;
 585                 }
 586
 587                 if (tip->ofile == NULL) {
 588                         perror(op);
 589                         return 1;
 590                 }
 591
 592                 tip->ofile_buffer = malloc(vbuf_size);
 593                 if (setvbuf(tip->ofile, tip->ofile_buffer, mode, vbuf_size)) {
 594                         perror("setvbuf");
 595                         close_thread(tip);
 596                         return 1;
 597                 }
 598
 599                 if (pthread_create(&tip->thread, NULL, thread_main, tip)) {
 600                         perror("pthread_create");
 601                         close_thread(tip);
 602                         return 1;
 603                 }
 604         }
 605
 606         return 0;
 607 }
 608
 609 static void stop_threads(struct device_information *dip)
 610 {
 611         struct thread_information *tip;
 612         unsigned long ret;
 613         int i;
 614
 615         for_each_tip(dip, tip, i) {
 616                 (void) pthread_join(tip->thread, (void *) &ret);
 617                 close_thread(tip);
 618         }
 619 }
 620
 621 static void stop_all_threads(void)
 622 {
 623         struct device_information *dip;
 624         int i;
 625
 626         for_each_dip(dip, i)
 627                 stop_threads(dip);
 628 }
 629
 630 static void stop_all_tracing(void)
 631 {
 632         struct device_information *dip;
 633         int i;
 634
 635         for_each_dip(dip, i)
 636                 stop_trace(dip);
 637 }
 638
 639 static void exit_trace(int status)
 640 {
 641         if (!is_trace_stopped()) {
 642                 trace_stopped = 1;
 643                 stop_all_threads();
 644                 stop_all_tracing();
 645         }
 646
 647         exit(status);
 648 }
 649
 650 static int resize_devices(char *path)
 651 {
 652         int size = (ndevs + 1) * sizeof(struct device_information);
 653
 654         device_information = realloc(device_information, size);
 655         if (!device_information) {
 656                 fprintf(stderr, "Out of memory, device %s (%d)\n", path, size);
 657                 return 1;
 658         }
 659         device_information[ndevs].path = path;
 660         ndevs++;
 661         return 0;
 662 }
 663
 664 static int open_devices(void)
 665 {
 666         struct device_information *dip;
 667         int i;
 668
 669         for_each_dip(dip, i) {
 670                 dip->fd = open(dip->path, O_RDONLY | O_NONBLOCK);
 671                 if (dip->fd < 0) {
 672                         perror(dip->path);
 673                         return 1;
 674                 }
 675         }
 676
 677         return 0;
 678 }
 679
 680 static int start_devices(void)
 681 {
 682         struct device_information *dip;
 683         int i, j, size;
 684
 685         size = ncpus * sizeof(struct thread_information);
 686         thread_information = malloc(size * ndevs);
 687         if (!thread_information) {
 688                 fprintf(stderr, "Out of memory, threads (%d)\n", size * ndevs);
 689                 return 1;
 690         }
 691
 692         for_each_dip(dip, i) {
 693                 if (start_trace(dip)) {
 694                         close(dip->fd);
 695                         fprintf(stderr, "Failed to start trace on %s\n",
 696                                 dip->path);
 697                         break;
 698                 }
 699         }
 700
 701         if (i != ndevs) {
 702                 __for_each_dip(dip, j, i)
 703                         stop_trace(dip);
 704
 705                 return 1;
 706         }
 707
 708         for_each_dip(dip, i) {
 709                 dip->threads = thread_information + (i * ncpus);
 710                 if (start_threads(dip)) {
 711                         fprintf(stderr, "Failed to start worker threads\n");
 712                         break;
 713                 }
 714         }
 715
 716         if (i != ndevs) {
 717                 __for_each_dip(dip, j, i)
 718                         stop_threads(dip);
 719                 for_each_dip(dip, i)
 720                         stop_trace(dip);
 721
 722                 return 1;
 723         }
 724
 725         return 0;
 726 }
 727
 728 static void show_stats(void)
 729 {
 730         struct device_information *dip;
 731         struct thread_information *tip;
 732         unsigned long long events_processed;
 733         unsigned long total_drops;
 734         int i, j, no_stdout = 0;
 735
 736         if (is_stat_shown())
 737                 return;
 738
 739         if (output_name && !strcmp(output_name, "-"))
 740                 no_stdout = 1;
 741
 742         stat_shown = 1;
 743
 744         total_drops = 0;
 745         for_each_dip(dip, i) {
 746                 if (!no_stdout)
 747                         printf("Device: %s\n", dip->path);
 748                 events_processed = 0;
 749                 for_each_tip(dip, tip, j) {
 750                         if (!no_stdout)
 751                                 printf("  CPU%3d: %20ld events\n",
 752                                         tip->cpu, tip->events_processed);
 753                         events_processed += tip->events_processed;
 754                 }
 755                 total_drops += dip->drop_count;
 756                 if (!no_stdout)
 757                         printf("  Total:  %20lld events (dropped %lu)\n",
 758                                         events_processed, dip->drop_count);
 759         }
 760
 761         if (total_drops)
 762                 fprintf(stderr, "You have dropped events, consider using a larger buffer size (-b)\n");
 763 }
 764
 765 static char usage_str[] = \
 766         "-d <dev> [ -r relay path ] [ -o <output> ] [-k ] [ -w time ]\n" \
 767         "[ -a action ] [ -A action mask ] [ -v ]\n\n" \
 768         "\t-d Use specified device. May also be given last after options\n" \
 769         "\t-r Path to mounted relayfs, defaults to /relay\n" \
 770         "\t-o File(s) to send output to\n" \
 771         "\t-D Directory to prepend to output file names\n" \
 772         "\t-k Kill a running trace\n" \
 773         "\t-w Stop after defined time, in seconds\n" \
 774         "\t-a Only trace specified actions. See documentation\n" \
 775         "\t-A Give trace mask as a single value. See documentation\n" \
 776         "\t-b Sub buffer size in KiB\n" \
 777         "\t-n Number of sub buffers\n" \
 778         "\t-v Print program version info\n\n";
 779
 780 static void show_usage(char *program)
 781 {
 782         fprintf(stderr, "Usage: %s %s %s",program, blktrace_version, usage_str);
 783 }
 784 static void handle_sigint(__attribute__((__unused__)) int sig)
 785 {
 786         done = 1;
 787 }
 788
 789 int main(int argc, char *argv[])
 790 {
 791         static char default_relay_path[] = "/relay";
 792         struct statfs st;
 793         int i, c;
 794         int stop_watch = 0;
 795         int act_mask_tmp = 0;
 796
 797         while ((c = getopt_long(argc, argv, S_OPTS, l_opts, NULL)) >= 0) {
 798                 switch (c) {
 799                 case 'a':
 800                         i = find_mask_map(optarg);
 801                         if (i < 0) {
 802                                 fprintf(stderr,"Invalid action mask %s\n",
 803                                         optarg);
 804                                 return 1;
 805                         }
 806                         act_mask_tmp |= i;
 807                         break;
 808
 809                 case 'A':
 810                         if ((sscanf(optarg, "%x", &i) != 1) ||
 811                                                         !valid_act_opt(i)) {
 812                                 fprintf(stderr,
 813                                         "Invalid set action mask %s/0x%x\n",
 814                                         optarg, i);
 815                                 return 1;
 816                         }
 817                         act_mask_tmp = i;
 818                         break;
 819
 820                 case 'd':
 821                         if (resize_devices(optarg) != 0)
 822                                 return 1;
 823                         break;
 824
 825                 case 'r':
 826                         relay_path = optarg;
 827                         break;
 828
 829                 case 'o':
 830                         output_name = optarg;
 831                         break;
 832                 case 'k':
 833                         kill_running_trace = 1;
 834                         break;
 835                 case 'w':
 836                         stop_watch = atoi(optarg);
 837                         if (stop_watch <= 0) {
 838                                 fprintf(stderr,
 839                                         "Invalid stopwatch value (%d secs)\n",
 840                                         stop_watch);
 841                                 return 1;
 842                         }
 843                         break;
 844                 case 'V':
 845                         printf("%s version %s\n", argv[0], blktrace_version);
 846                         return 0;
 847                 case 'b':
 848                         buf_size = strtoul(optarg, NULL, 10);
 849                         if (buf_size <= 0 || buf_size > 16*1024) {
 850                                 fprintf(stderr,
 851                                         "Invalid buffer size (%lu)\n",buf_size);
 852                                 return 1;
 853                         }
 854                         buf_size <<= 10;
 855                         break;
 856                 case 'n':
 857                         buf_nr = strtoul(optarg, NULL, 10);
 858                         if (buf_nr <= 0) {
 859                                 fprintf(stderr,
 860                                         "Invalid buffer nr (%lu)\n", buf_nr);
 861                                 return 1;
 862                         }
 863                         break;
 864                 case 'D':
 865                         output_dir = optarg;
 866                         break;
 867                 default:
 868                         show_usage(argv[0]);
 869                         return 1;
 870                 }
 871         }
 872
 873         while (optind < argc) {
 874                 if (resize_devices(argv[optind++]) != 0)
 875                         return 1;
 876         }
 877
 878         if (ndevs == 0) {
 879                 show_usage(argv[0]);
 880                 return 1;
 881         }
 882
 883         if (!relay_path)
 884                 relay_path = default_relay_path;
 885
 886         if (act_mask_tmp != 0)
 887                 act_mask = act_mask_tmp;
 888
 889         if (statfs(relay_path, &st) < 0) {
 890                 perror("statfs");
 891                 fprintf(stderr,"%s does not appear to be a valid path\n",
 892                         relay_path);
 893                 return 1;
 894         } else if (st.f_type != (long) RELAYFS_TYPE) {
 895                 fprintf(stderr,"%s does not appear to be a relay filesystem\n",
 896                         relay_path);
 897                 return 1;
 898         }
 899
 900         if (open_devices() != 0)
 901                 return 1;
 902
 903         if (kill_running_trace) {
 904                 stop_all_traces();
 905                 return 0;
 906         }
 907
 908         setlocale(LC_NUMERIC, "en_US");
 909
 910         ncpus = sysconf(_SC_NPROCESSORS_ONLN);
 911         if (ncpus < 0) {
 912                 fprintf(stderr, "sysconf(_SC_NPROCESSORS_ONLN) failed\n");
 913                 return 1;
 914         }
 915
 916         if (start_devices() != 0)
 917                 return 1;
 918
 919         signal(SIGINT, handle_sigint);
 920         signal(SIGHUP, handle_sigint);
 921         signal(SIGTERM, handle_sigint);
 922         signal(SIGALRM, handle_sigint);
 923
 924         atexit(stop_all_tracing);
 925
 926         if (stop_watch)
 927                 alarm(stop_watch);
 928
 929         get_and_write_events();
 930
 931         if (!is_trace_stopped()) {
 932                 trace_stopped = 1;
 933                 stop_all_threads();
 934                 stop_all_traces();
 935         }
 936
 937         show_stats();
 938
 939         return 0;
 940 }
 941