| 1 | /* |
| 2 | * blktrace support code for fio |
| 3 | */ |
| 4 | #include <stdio.h> |
| 5 | #include <stdlib.h> |
| 6 | #include <sys/stat.h> |
| 7 | #include <dirent.h> |
| 8 | |
| 9 | #include "flist.h" |
| 10 | #include "fio.h" |
| 11 | #include "blktrace_api.h" |
| 12 | |
| 13 | #define TRACE_FIFO_SIZE 8192 |
| 14 | |
| 15 | /* |
| 16 | * fifo refill frontend, to avoid reading data in trace sized bites |
| 17 | */ |
| 18 | static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd) |
| 19 | { |
| 20 | char buf[TRACE_FIFO_SIZE]; |
| 21 | unsigned int total; |
| 22 | int ret; |
| 23 | |
| 24 | total = sizeof(buf); |
| 25 | if (total > fifo_room(fifo)) |
| 26 | total = fifo_room(fifo); |
| 27 | |
| 28 | ret = read(fd, buf, total); |
| 29 | if (ret < 0) { |
| 30 | td_verror(td, errno, "read blktrace file"); |
| 31 | return -1; |
| 32 | } |
| 33 | |
| 34 | if (ret > 0) |
| 35 | ret = fifo_put(fifo, buf, ret); |
| 36 | |
| 37 | dprint(FD_BLKTRACE, "refill: filled %d bytes\n", ret); |
| 38 | return ret; |
| 39 | } |
| 40 | |
| 41 | /* |
| 42 | * Retrieve 'len' bytes from the fifo, refilling if necessary. |
| 43 | */ |
| 44 | static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd, |
| 45 | void *buf, unsigned int len) |
| 46 | { |
| 47 | if (fifo_len(fifo) < len) { |
| 48 | int ret = refill_fifo(td, fifo, fd); |
| 49 | |
| 50 | if (ret < 0) |
| 51 | return ret; |
| 52 | } |
| 53 | |
| 54 | return fifo_get(fifo, buf, len); |
| 55 | } |
| 56 | |
| 57 | /* |
| 58 | * Just discard the pdu by seeking past it. |
| 59 | */ |
| 60 | static int discard_pdu(struct thread_data *td, struct fifo *fifo, int fd, |
| 61 | struct blk_io_trace *t) |
| 62 | { |
| 63 | if (t->pdu_len == 0) |
| 64 | return 0; |
| 65 | |
| 66 | dprint(FD_BLKTRACE, "discard pdu len %u\n", t->pdu_len); |
| 67 | return trace_fifo_get(td, fifo, fd, NULL, t->pdu_len); |
| 68 | } |
| 69 | |
| 70 | /* |
| 71 | * Check if this is a blktrace binary data file. We read a single trace |
| 72 | * into memory and check for the magic signature. |
| 73 | */ |
| 74 | int is_blktrace(const char *filename, int *need_swap) |
| 75 | { |
| 76 | struct blk_io_trace t; |
| 77 | int fd, ret; |
| 78 | |
| 79 | fd = open(filename, O_RDONLY); |
| 80 | if (fd < 0) |
| 81 | return 0; |
| 82 | |
| 83 | ret = read(fd, &t, sizeof(t)); |
| 84 | close(fd); |
| 85 | |
| 86 | if (ret < 0) { |
| 87 | perror("read blktrace"); |
| 88 | return 0; |
| 89 | } else if (ret != sizeof(t)) { |
| 90 | log_err("fio: short read on blktrace file\n"); |
| 91 | return 0; |
| 92 | } |
| 93 | |
| 94 | if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC) { |
| 95 | *need_swap = 0; |
| 96 | return 1; |
| 97 | } |
| 98 | |
| 99 | /* |
| 100 | * Maybe it needs to be endian swapped... |
| 101 | */ |
| 102 | t.magic = fio_swap32(t.magic); |
| 103 | if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC) { |
| 104 | *need_swap = 1; |
| 105 | return 1; |
| 106 | } |
| 107 | |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | static int lookup_device(struct thread_data *td, char *path, unsigned int maj, |
| 112 | unsigned int min) |
| 113 | { |
| 114 | struct dirent *dir; |
| 115 | struct stat st; |
| 116 | int found = 0; |
| 117 | DIR *D; |
| 118 | |
| 119 | D = opendir(path); |
| 120 | if (!D) |
| 121 | return 0; |
| 122 | |
| 123 | while ((dir = readdir(D)) != NULL) { |
| 124 | char full_path[256]; |
| 125 | |
| 126 | if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, "..")) |
| 127 | continue; |
| 128 | |
| 129 | sprintf(full_path, "%s%s%s", path, FIO_OS_PATH_SEPARATOR, dir->d_name); |
| 130 | if (lstat(full_path, &st) == -1) { |
| 131 | perror("lstat"); |
| 132 | break; |
| 133 | } |
| 134 | |
| 135 | if (S_ISDIR(st.st_mode)) { |
| 136 | found = lookup_device(td, full_path, maj, min); |
| 137 | if (found) { |
| 138 | strcpy(path, full_path); |
| 139 | break; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | if (!S_ISBLK(st.st_mode)) |
| 144 | continue; |
| 145 | |
| 146 | /* |
| 147 | * If replay_redirect is set then always return this device |
| 148 | * upon lookup which overrides the device lookup based on |
| 149 | * major minor in the actual blktrace |
| 150 | */ |
| 151 | if (td->o.replay_redirect) { |
| 152 | dprint(FD_BLKTRACE, "device lookup: %d/%d\n overridden" |
| 153 | " with: %s\n", maj, min, |
| 154 | td->o.replay_redirect); |
| 155 | strcpy(path, td->o.replay_redirect); |
| 156 | found = 1; |
| 157 | break; |
| 158 | } |
| 159 | |
| 160 | if (maj == major(st.st_rdev) && min == minor(st.st_rdev)) { |
| 161 | dprint(FD_BLKTRACE, "device lookup: %d/%d\n", maj, min); |
| 162 | strcpy(path, full_path); |
| 163 | found = 1; |
| 164 | break; |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | closedir(D); |
| 169 | return found; |
| 170 | } |
| 171 | |
| 172 | #define FMINORBITS 20 |
| 173 | #define FMINORMASK ((1U << FMINORBITS) - 1) |
| 174 | #define FMAJOR(dev) ((unsigned int) ((dev) >> FMINORBITS)) |
| 175 | #define FMINOR(dev) ((unsigned int) ((dev) & FMINORMASK)) |
| 176 | |
| 177 | static void trace_add_open_close_event(struct thread_data *td, int fileno, enum file_log_act action) |
| 178 | { |
| 179 | struct io_piece *ipo; |
| 180 | |
| 181 | ipo = calloc(1, sizeof(*ipo)); |
| 182 | init_ipo(ipo); |
| 183 | |
| 184 | ipo->ddir = DDIR_INVAL; |
| 185 | ipo->fileno = fileno; |
| 186 | ipo->file_action = action; |
| 187 | flist_add_tail(&ipo->list, &td->io_log_list); |
| 188 | } |
| 189 | |
| 190 | static int trace_add_file(struct thread_data *td, __u32 device) |
| 191 | { |
| 192 | static unsigned int last_maj, last_min, last_fileno; |
| 193 | unsigned int maj = FMAJOR(device); |
| 194 | unsigned int min = FMINOR(device); |
| 195 | struct fio_file *f; |
| 196 | char dev[256]; |
| 197 | unsigned int i; |
| 198 | |
| 199 | if (last_maj == maj && last_min == min) |
| 200 | return last_fileno; |
| 201 | |
| 202 | last_maj = maj; |
| 203 | last_min = min; |
| 204 | |
| 205 | /* |
| 206 | * check for this file in our list |
| 207 | */ |
| 208 | for_each_file(td, f, i) |
| 209 | if (f->major == maj && f->minor == min) { |
| 210 | last_fileno = f->fileno; |
| 211 | return last_fileno; |
| 212 | } |
| 213 | |
| 214 | strcpy(dev, "/dev"); |
| 215 | if (lookup_device(td, dev, maj, min)) { |
| 216 | int fileno; |
| 217 | |
| 218 | dprint(FD_BLKTRACE, "add devices %s\n", dev); |
| 219 | fileno = add_file_exclusive(td, dev); |
| 220 | td->o.open_files++; |
| 221 | td->files[fileno]->major = maj; |
| 222 | td->files[fileno]->minor = min; |
| 223 | trace_add_open_close_event(td, fileno, FIO_LOG_OPEN_FILE); |
| 224 | last_fileno = fileno; |
| 225 | } |
| 226 | |
| 227 | return last_fileno; |
| 228 | } |
| 229 | |
| 230 | /* |
| 231 | * Store blk_io_trace data in an ipo for later retrieval. |
| 232 | */ |
| 233 | static void store_ipo(struct thread_data *td, unsigned long long offset, |
| 234 | unsigned int bytes, int rw, unsigned long long ttime, |
| 235 | int fileno) |
| 236 | { |
| 237 | struct io_piece *ipo = malloc(sizeof(*ipo)); |
| 238 | |
| 239 | init_ipo(ipo); |
| 240 | |
| 241 | /* |
| 242 | * the 512 is wrong here, it should be the hardware sector size... |
| 243 | */ |
| 244 | ipo->offset = offset * 512; |
| 245 | ipo->len = bytes; |
| 246 | ipo->delay = ttime / 1000; |
| 247 | if (rw) |
| 248 | ipo->ddir = DDIR_WRITE; |
| 249 | else |
| 250 | ipo->ddir = DDIR_READ; |
| 251 | ipo->fileno = fileno; |
| 252 | |
| 253 | dprint(FD_BLKTRACE, "store ddir=%d, off=%llu, len=%lu, delay=%lu\n", |
| 254 | ipo->ddir, ipo->offset, |
| 255 | ipo->len, ipo->delay); |
| 256 | queue_io_piece(td, ipo); |
| 257 | } |
| 258 | |
| 259 | static void handle_trace_notify(struct blk_io_trace *t) |
| 260 | { |
| 261 | switch (t->action) { |
| 262 | case BLK_TN_PROCESS: |
| 263 | log_info("blktrace: got process notify: %x, %d\n", |
| 264 | t->action, t->pid); |
| 265 | break; |
| 266 | case BLK_TN_TIMESTAMP: |
| 267 | log_info("blktrace: got timestamp notify: %x, %d\n", |
| 268 | t->action, t->pid); |
| 269 | break; |
| 270 | case BLK_TN_MESSAGE: |
| 271 | break; |
| 272 | default: |
| 273 | dprint(FD_BLKTRACE, "unknown trace act %x\n", t->action); |
| 274 | break; |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | static void handle_trace_discard(struct thread_data *td, struct blk_io_trace *t, |
| 279 | unsigned long long ttime, unsigned long *ios) |
| 280 | { |
| 281 | struct io_piece *ipo = malloc(sizeof(*ipo)); |
| 282 | int fileno; |
| 283 | |
| 284 | init_ipo(ipo); |
| 285 | fileno = trace_add_file(td, t->device); |
| 286 | |
| 287 | ios[DDIR_WRITE]++; |
| 288 | td->o.size += t->bytes; |
| 289 | |
| 290 | memset(ipo, 0, sizeof(*ipo)); |
| 291 | INIT_FLIST_HEAD(&ipo->list); |
| 292 | |
| 293 | /* |
| 294 | * the 512 is wrong here, it should be the hardware sector size... |
| 295 | */ |
| 296 | ipo->offset = t->sector * 512; |
| 297 | ipo->len = t->bytes; |
| 298 | ipo->delay = ttime / 1000; |
| 299 | ipo->ddir = DDIR_TRIM; |
| 300 | ipo->fileno = fileno; |
| 301 | |
| 302 | dprint(FD_BLKTRACE, "store discard, off=%llu, len=%lu, delay=%lu\n", |
| 303 | ipo->offset, ipo->len, |
| 304 | ipo->delay); |
| 305 | queue_io_piece(td, ipo); |
| 306 | } |
| 307 | |
| 308 | static void handle_trace_fs(struct thread_data *td, struct blk_io_trace *t, |
| 309 | unsigned long long ttime, unsigned long *ios, |
| 310 | unsigned int *bs) |
| 311 | { |
| 312 | int rw; |
| 313 | int fileno; |
| 314 | |
| 315 | fileno = trace_add_file(td, t->device); |
| 316 | |
| 317 | rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0; |
| 318 | |
| 319 | if (t->bytes > bs[rw]) |
| 320 | bs[rw] = t->bytes; |
| 321 | |
| 322 | ios[rw]++; |
| 323 | td->o.size += t->bytes; |
| 324 | store_ipo(td, t->sector, t->bytes, rw, ttime, fileno); |
| 325 | } |
| 326 | |
| 327 | /* |
| 328 | * We only care for queue traces, most of the others are side effects |
| 329 | * due to internal workings of the block layer. |
| 330 | */ |
| 331 | static void handle_trace(struct thread_data *td, struct blk_io_trace *t, |
| 332 | unsigned long long ttime, unsigned long *ios, |
| 333 | unsigned int *bs) |
| 334 | { |
| 335 | if ((t->action & 0xffff) != __BLK_TA_QUEUE) |
| 336 | return; |
| 337 | if (t->action & BLK_TC_ACT(BLK_TC_PC)) |
| 338 | return; |
| 339 | |
| 340 | if (t->action & BLK_TC_ACT(BLK_TC_NOTIFY)) |
| 341 | handle_trace_notify(t); |
| 342 | else if (t->action & BLK_TC_ACT(BLK_TC_DISCARD)) |
| 343 | handle_trace_discard(td, t, ttime, ios); |
| 344 | else |
| 345 | handle_trace_fs(td, t, ttime, ios, bs); |
| 346 | } |
| 347 | |
| 348 | static void byteswap_trace(struct blk_io_trace *t) |
| 349 | { |
| 350 | t->magic = fio_swap32(t->magic); |
| 351 | t->sequence = fio_swap32(t->sequence); |
| 352 | t->time = fio_swap64(t->time); |
| 353 | t->sector = fio_swap64(t->sector); |
| 354 | t->bytes = fio_swap32(t->bytes); |
| 355 | t->action = fio_swap32(t->action); |
| 356 | t->pid = fio_swap32(t->pid); |
| 357 | t->device = fio_swap32(t->device); |
| 358 | t->cpu = fio_swap32(t->cpu); |
| 359 | t->error = fio_swap16(t->error); |
| 360 | t->pdu_len = fio_swap16(t->pdu_len); |
| 361 | } |
| 362 | |
| 363 | /* |
| 364 | * Load a blktrace file by reading all the blk_io_trace entries, and storing |
| 365 | * them as io_pieces like the fio text version would do. |
| 366 | */ |
| 367 | int load_blktrace(struct thread_data *td, const char *filename, int need_swap) |
| 368 | { |
| 369 | unsigned long long ttime, delay; |
| 370 | struct blk_io_trace t; |
| 371 | unsigned long ios[2], skipped_writes; |
| 372 | unsigned int cpu; |
| 373 | unsigned int rw_bs[2]; |
| 374 | struct fifo *fifo; |
| 375 | int fd, i, old_state; |
| 376 | struct fio_file *f; |
| 377 | int this_depth, depth; |
| 378 | |
| 379 | fd = open(filename, O_RDONLY); |
| 380 | if (fd < 0) { |
| 381 | td_verror(td, errno, "open blktrace file"); |
| 382 | return 1; |
| 383 | } |
| 384 | |
| 385 | fifo = fifo_alloc(TRACE_FIFO_SIZE); |
| 386 | |
| 387 | old_state = td_bump_runstate(td, TD_SETTING_UP); |
| 388 | |
| 389 | td->o.size = 0; |
| 390 | |
| 391 | cpu = 0; |
| 392 | ttime = 0; |
| 393 | ios[0] = ios[1] = 0; |
| 394 | rw_bs[0] = rw_bs[1] = 0; |
| 395 | skipped_writes = 0; |
| 396 | this_depth = depth = 0; |
| 397 | do { |
| 398 | int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t)); |
| 399 | |
| 400 | if (ret < 0) |
| 401 | goto err; |
| 402 | else if (!ret) |
| 403 | break; |
| 404 | else if (ret < (int) sizeof(t)) { |
| 405 | log_err("fio: short fifo get\n"); |
| 406 | break; |
| 407 | } |
| 408 | |
| 409 | if (need_swap) |
| 410 | byteswap_trace(&t); |
| 411 | |
| 412 | if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) { |
| 413 | log_err("fio: bad magic in blktrace data: %x\n", |
| 414 | t.magic); |
| 415 | goto err; |
| 416 | } |
| 417 | if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) { |
| 418 | log_err("fio: bad blktrace version %d\n", |
| 419 | t.magic & 0xff); |
| 420 | goto err; |
| 421 | } |
| 422 | ret = discard_pdu(td, fifo, fd, &t); |
| 423 | if (ret < 0) { |
| 424 | td_verror(td, ret, "blktrace lseek"); |
| 425 | goto err; |
| 426 | } else if (t.pdu_len != ret) { |
| 427 | log_err("fio: discarded %d of %d\n", ret, t.pdu_len); |
| 428 | goto err; |
| 429 | } |
| 430 | if ((t.action & BLK_TC_ACT(BLK_TC_NOTIFY)) == 0) { |
| 431 | if ((t.action & 0xffff) == __BLK_TA_QUEUE) |
| 432 | this_depth++; |
| 433 | else if ((t.action & 0xffff) == __BLK_TA_COMPLETE) { |
| 434 | depth = max(depth, this_depth); |
| 435 | this_depth = 0; |
| 436 | } |
| 437 | if (!ttime) { |
| 438 | ttime = t.time; |
| 439 | cpu = t.cpu; |
| 440 | } |
| 441 | |
| 442 | delay = 0; |
| 443 | if (cpu == t.cpu) |
| 444 | delay = t.time - ttime; |
| 445 | if ((t.action & BLK_TC_ACT(BLK_TC_WRITE)) && read_only) |
| 446 | skipped_writes++; |
| 447 | else { |
| 448 | /* |
| 449 | * set delay to zero if no_stall enabled for |
| 450 | * fast replay |
| 451 | */ |
| 452 | if (td->o.no_stall) |
| 453 | delay = 0; |
| 454 | |
| 455 | handle_trace(td, &t, delay, ios, rw_bs); |
| 456 | } |
| 457 | |
| 458 | ttime = t.time; |
| 459 | cpu = t.cpu; |
| 460 | } else { |
| 461 | delay = 0; |
| 462 | handle_trace(td, &t, delay, ios, rw_bs); |
| 463 | } |
| 464 | } while (1); |
| 465 | |
| 466 | for (i = 0; i < td->files_index; i++) { |
| 467 | f = td->files[i]; |
| 468 | trace_add_open_close_event(td, f->fileno, FIO_LOG_CLOSE_FILE); |
| 469 | } |
| 470 | |
| 471 | fifo_free(fifo); |
| 472 | close(fd); |
| 473 | |
| 474 | td_restore_runstate(td, old_state); |
| 475 | |
| 476 | if (!td->files_index) { |
| 477 | log_err("fio: did not find replay device(s)\n"); |
| 478 | return 1; |
| 479 | } |
| 480 | |
| 481 | /* |
| 482 | * For stacked devices, we don't always get a COMPLETE event so |
| 483 | * the depth grows to insane values. Limit it to something sane(r). |
| 484 | */ |
| 485 | if (!depth || depth > 1024) |
| 486 | depth = 1024; |
| 487 | |
| 488 | if (skipped_writes) |
| 489 | log_err("fio: %s skips replay of %lu writes due to read-only\n", |
| 490 | td->o.name, skipped_writes); |
| 491 | |
| 492 | if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) { |
| 493 | log_err("fio: found no ios in blktrace data\n"); |
| 494 | return 1; |
| 495 | } else if (ios[DDIR_READ] && !ios[DDIR_READ]) { |
| 496 | td->o.td_ddir = TD_DDIR_READ; |
| 497 | td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ]; |
| 498 | } else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) { |
| 499 | td->o.td_ddir = TD_DDIR_WRITE; |
| 500 | td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE]; |
| 501 | } else { |
| 502 | td->o.td_ddir = TD_DDIR_RW; |
| 503 | td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ]; |
| 504 | td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE]; |
| 505 | } |
| 506 | |
| 507 | /* |
| 508 | * We need to do direct/raw ios to the device, to avoid getting |
| 509 | * read-ahead in our way. |
| 510 | */ |
| 511 | td->o.odirect = 1; |
| 512 | |
| 513 | /* |
| 514 | * we don't know if this option was set or not. it defaults to 1, |
| 515 | * so we'll just guess that we should override it if it's still 1 |
| 516 | */ |
| 517 | if (td->o.iodepth != 1) |
| 518 | td->o.iodepth = depth; |
| 519 | |
| 520 | return 0; |
| 521 | err: |
| 522 | close(fd); |
| 523 | fifo_free(fifo); |
| 524 | return 1; |
| 525 | } |