| 1 | /* |
| 2 | * Clock functions |
| 3 | */ |
| 4 | |
| 5 | #include <math.h> |
| 6 | |
| 7 | #include "fio.h" |
| 8 | #include "os/os.h" |
| 9 | |
| 10 | #if defined(ARCH_HAVE_CPU_CLOCK) |
| 11 | #ifndef ARCH_CPU_CLOCK_CYCLES_PER_USEC |
| 12 | static unsigned long long cycles_per_msec; |
| 13 | static unsigned long long cycles_start; |
| 14 | static unsigned long long clock_mult; |
| 15 | static unsigned long long max_cycles_mask; |
| 16 | static unsigned long long nsecs_for_max_cycles; |
| 17 | static unsigned int clock_shift; |
| 18 | static unsigned int max_cycles_shift; |
| 19 | #define MAX_CLOCK_SEC 60*60 |
| 20 | #endif |
| 21 | #ifdef ARCH_CPU_CLOCK_WRAPS |
| 22 | static unsigned int cycles_wrap; |
| 23 | #endif |
| 24 | #endif |
| 25 | bool tsc_reliable = false; |
| 26 | |
| 27 | struct tv_valid { |
| 28 | int warned; |
| 29 | }; |
| 30 | #ifdef ARCH_HAVE_CPU_CLOCK |
| 31 | #ifdef CONFIG_TLS_THREAD |
| 32 | static __thread struct tv_valid static_tv_valid; |
| 33 | #else |
| 34 | static pthread_key_t tv_tls_key; |
| 35 | #endif |
| 36 | #endif |
| 37 | |
| 38 | enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE; |
| 39 | int fio_clock_source_set = 0; |
| 40 | static enum fio_cs fio_clock_source_inited = CS_INVAL; |
| 41 | |
| 42 | #ifdef FIO_DEBUG_TIME |
| 43 | |
| 44 | #define HASH_BITS 8 |
| 45 | #define HASH_SIZE (1 << HASH_BITS) |
| 46 | |
| 47 | static struct flist_head hash[HASH_SIZE]; |
| 48 | static int gtod_inited; |
| 49 | |
| 50 | struct gtod_log { |
| 51 | struct flist_head list; |
| 52 | void *caller; |
| 53 | unsigned long calls; |
| 54 | }; |
| 55 | |
| 56 | static struct gtod_log *find_hash(void *caller) |
| 57 | { |
| 58 | unsigned long h = hash_ptr(caller, HASH_BITS); |
| 59 | struct flist_head *entry; |
| 60 | |
| 61 | flist_for_each(entry, &hash[h]) { |
| 62 | struct gtod_log *log = flist_entry(entry, struct gtod_log, |
| 63 | list); |
| 64 | |
| 65 | if (log->caller == caller) |
| 66 | return log; |
| 67 | } |
| 68 | |
| 69 | return NULL; |
| 70 | } |
| 71 | |
| 72 | static void inc_caller(void *caller) |
| 73 | { |
| 74 | struct gtod_log *log = find_hash(caller); |
| 75 | |
| 76 | if (!log) { |
| 77 | unsigned long h; |
| 78 | |
| 79 | log = malloc(sizeof(*log)); |
| 80 | INIT_FLIST_HEAD(&log->list); |
| 81 | log->caller = caller; |
| 82 | log->calls = 0; |
| 83 | |
| 84 | h = hash_ptr(caller, HASH_BITS); |
| 85 | flist_add_tail(&log->list, &hash[h]); |
| 86 | } |
| 87 | |
| 88 | log->calls++; |
| 89 | } |
| 90 | |
| 91 | static void gtod_log_caller(void *caller) |
| 92 | { |
| 93 | if (gtod_inited) |
| 94 | inc_caller(caller); |
| 95 | } |
| 96 | |
| 97 | static void fio_exit fio_dump_gtod(void) |
| 98 | { |
| 99 | unsigned long total_calls = 0; |
| 100 | int i; |
| 101 | |
| 102 | for (i = 0; i < HASH_SIZE; i++) { |
| 103 | struct flist_head *entry; |
| 104 | struct gtod_log *log; |
| 105 | |
| 106 | flist_for_each(entry, &hash[i]) { |
| 107 | log = flist_entry(entry, struct gtod_log, list); |
| 108 | |
| 109 | printf("function %p, calls %lu\n", log->caller, |
| 110 | log->calls); |
| 111 | total_calls += log->calls; |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | printf("Total %lu gettimeofday\n", total_calls); |
| 116 | } |
| 117 | |
| 118 | static void fio_init gtod_init(void) |
| 119 | { |
| 120 | int i; |
| 121 | |
| 122 | for (i = 0; i < HASH_SIZE; i++) |
| 123 | INIT_FLIST_HEAD(&hash[i]); |
| 124 | |
| 125 | gtod_inited = 1; |
| 126 | } |
| 127 | |
| 128 | #endif /* FIO_DEBUG_TIME */ |
| 129 | |
| 130 | #ifdef CONFIG_CLOCK_GETTIME |
| 131 | static int fill_clock_gettime(struct timespec *ts) |
| 132 | { |
| 133 | #if defined(CONFIG_CLOCK_MONOTONIC_RAW) |
| 134 | return clock_gettime(CLOCK_MONOTONIC_RAW, ts); |
| 135 | #elif defined(CONFIG_CLOCK_MONOTONIC) |
| 136 | return clock_gettime(CLOCK_MONOTONIC, ts); |
| 137 | #else |
| 138 | return clock_gettime(CLOCK_REALTIME, ts); |
| 139 | #endif |
| 140 | } |
| 141 | #endif |
| 142 | |
| 143 | static void __fio_gettime(struct timespec *tp) |
| 144 | { |
| 145 | switch (fio_clock_source) { |
| 146 | #ifdef CONFIG_GETTIMEOFDAY |
| 147 | case CS_GTOD: { |
| 148 | struct timeval tv; |
| 149 | gettimeofday(&tv, NULL); |
| 150 | |
| 151 | tp->tv_sec = tv.tv_sec; |
| 152 | tp->tv_nsec = tv.tv_usec * 1000; |
| 153 | break; |
| 154 | } |
| 155 | #endif |
| 156 | #ifdef CONFIG_CLOCK_GETTIME |
| 157 | case CS_CGETTIME: { |
| 158 | if (fill_clock_gettime(tp) < 0) { |
| 159 | log_err("fio: clock_gettime fails\n"); |
| 160 | assert(0); |
| 161 | } |
| 162 | break; |
| 163 | } |
| 164 | #endif |
| 165 | #ifdef ARCH_HAVE_CPU_CLOCK |
| 166 | case CS_CPUCLOCK: { |
| 167 | uint64_t nsecs, t, multiples; |
| 168 | struct tv_valid *tv; |
| 169 | |
| 170 | #ifdef CONFIG_TLS_THREAD |
| 171 | tv = &static_tv_valid; |
| 172 | #else |
| 173 | tv = pthread_getspecific(tv_tls_key); |
| 174 | #endif |
| 175 | |
| 176 | t = get_cpu_clock(); |
| 177 | #ifdef ARCH_CPU_CLOCK_WRAPS |
| 178 | if (t < cycles_start && !cycles_wrap) |
| 179 | cycles_wrap = 1; |
| 180 | else if (cycles_wrap && t >= cycles_start && !tv->warned) { |
| 181 | log_err("fio: double CPU clock wrap\n"); |
| 182 | tv->warned = 1; |
| 183 | } |
| 184 | #endif |
| 185 | #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC |
| 186 | nsecs = t / ARCH_CPU_CLOCK_CYCLES_PER_USEC * 1000; |
| 187 | #else |
| 188 | t -= cycles_start; |
| 189 | multiples = t >> max_cycles_shift; |
| 190 | nsecs = multiples * nsecs_for_max_cycles; |
| 191 | nsecs += ((t & max_cycles_mask) * clock_mult) >> clock_shift; |
| 192 | #endif |
| 193 | tp->tv_sec = nsecs / 1000000000ULL; |
| 194 | tp->tv_nsec = nsecs % 1000000000ULL; |
| 195 | break; |
| 196 | } |
| 197 | #endif |
| 198 | default: |
| 199 | log_err("fio: invalid clock source %d\n", fio_clock_source); |
| 200 | break; |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | #ifdef FIO_DEBUG_TIME |
| 205 | void fio_gettime(struct timespec *tp, void *caller) |
| 206 | #else |
| 207 | void fio_gettime(struct timespec *tp, void fio_unused *caller) |
| 208 | #endif |
| 209 | { |
| 210 | #ifdef FIO_DEBUG_TIME |
| 211 | if (!caller) |
| 212 | caller = __builtin_return_address(0); |
| 213 | |
| 214 | gtod_log_caller(caller); |
| 215 | #endif |
| 216 | if (fio_unlikely(fio_gettime_offload(tp))) |
| 217 | return; |
| 218 | |
| 219 | __fio_gettime(tp); |
| 220 | } |
| 221 | |
| 222 | #if defined(ARCH_HAVE_CPU_CLOCK) && !defined(ARCH_CPU_CLOCK_CYCLES_PER_USEC) |
| 223 | static unsigned long get_cycles_per_msec(void) |
| 224 | { |
| 225 | struct timespec s, e; |
| 226 | uint64_t c_s, c_e; |
| 227 | enum fio_cs old_cs = fio_clock_source; |
| 228 | uint64_t elapsed; |
| 229 | |
| 230 | #ifdef CONFIG_CLOCK_GETTIME |
| 231 | fio_clock_source = CS_CGETTIME; |
| 232 | #else |
| 233 | fio_clock_source = CS_GTOD; |
| 234 | #endif |
| 235 | __fio_gettime(&s); |
| 236 | |
| 237 | c_s = get_cpu_clock(); |
| 238 | do { |
| 239 | __fio_gettime(&e); |
| 240 | |
| 241 | elapsed = utime_since(&s, &e); |
| 242 | if (elapsed >= 1280) { |
| 243 | c_e = get_cpu_clock(); |
| 244 | break; |
| 245 | } |
| 246 | } while (1); |
| 247 | |
| 248 | fio_clock_source = old_cs; |
| 249 | return (c_e - c_s) * 1000 / elapsed; |
| 250 | } |
| 251 | |
| 252 | #define NR_TIME_ITERS 50 |
| 253 | |
| 254 | static int calibrate_cpu_clock(void) |
| 255 | { |
| 256 | double delta, mean, S; |
| 257 | uint64_t minc, maxc, avg, cycles[NR_TIME_ITERS]; |
| 258 | int i, samples, sft = 0; |
| 259 | unsigned long long tmp, max_ticks, max_mult; |
| 260 | |
| 261 | cycles[0] = get_cycles_per_msec(); |
| 262 | S = delta = mean = 0.0; |
| 263 | for (i = 0; i < NR_TIME_ITERS; i++) { |
| 264 | cycles[i] = get_cycles_per_msec(); |
| 265 | delta = cycles[i] - mean; |
| 266 | if (delta) { |
| 267 | mean += delta / (i + 1.0); |
| 268 | S += delta * (cycles[i] - mean); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | /* |
| 273 | * The most common platform clock breakage is returning zero |
| 274 | * indefinitely. Check for that and return failure. |
| 275 | */ |
| 276 | if (!cycles[0] && !cycles[NR_TIME_ITERS - 1]) |
| 277 | return 1; |
| 278 | |
| 279 | S = sqrt(S / (NR_TIME_ITERS - 1.0)); |
| 280 | |
| 281 | minc = -1ULL; |
| 282 | maxc = samples = avg = 0; |
| 283 | for (i = 0; i < NR_TIME_ITERS; i++) { |
| 284 | double this = cycles[i]; |
| 285 | |
| 286 | minc = min(cycles[i], minc); |
| 287 | maxc = max(cycles[i], maxc); |
| 288 | |
| 289 | if ((fmax(this, mean) - fmin(this, mean)) > S) |
| 290 | continue; |
| 291 | samples++; |
| 292 | avg += this; |
| 293 | } |
| 294 | |
| 295 | S /= (double) NR_TIME_ITERS; |
| 296 | |
| 297 | for (i = 0; i < NR_TIME_ITERS; i++) |
| 298 | dprint(FD_TIME, "cycles[%d]=%llu\n", i, (unsigned long long) cycles[i]); |
| 299 | |
| 300 | avg /= samples; |
| 301 | cycles_per_msec = avg; |
| 302 | dprint(FD_TIME, "avg: %llu\n", (unsigned long long) avg); |
| 303 | dprint(FD_TIME, "min=%llu, max=%llu, mean=%f, S=%f\n", |
| 304 | (unsigned long long) minc, |
| 305 | (unsigned long long) maxc, mean, S); |
| 306 | |
| 307 | max_ticks = MAX_CLOCK_SEC * cycles_per_msec * 1000ULL; |
| 308 | max_mult = ULLONG_MAX / max_ticks; |
| 309 | dprint(FD_TIME, "\n\nmax_ticks=%llu, __builtin_clzll=%d, " |
| 310 | "max_mult=%llu\n", max_ticks, |
| 311 | __builtin_clzll(max_ticks), max_mult); |
| 312 | |
| 313 | /* |
| 314 | * Find the largest shift count that will produce |
| 315 | * a multiplier that does not exceed max_mult |
| 316 | */ |
| 317 | tmp = max_mult * cycles_per_msec / 1000000; |
| 318 | while (tmp > 1) { |
| 319 | tmp >>= 1; |
| 320 | sft++; |
| 321 | dprint(FD_TIME, "tmp=%llu, sft=%u\n", tmp, sft); |
| 322 | } |
| 323 | |
| 324 | clock_shift = sft; |
| 325 | clock_mult = (1ULL << sft) * 1000000 / cycles_per_msec; |
| 326 | dprint(FD_TIME, "clock_shift=%u, clock_mult=%llu\n", clock_shift, |
| 327 | clock_mult); |
| 328 | |
| 329 | /* |
| 330 | * Find the greatest power of 2 clock ticks that is less than the |
| 331 | * ticks in MAX_CLOCK_SEC_2STAGE |
| 332 | */ |
| 333 | max_cycles_shift = max_cycles_mask = 0; |
| 334 | tmp = MAX_CLOCK_SEC * 1000ULL * cycles_per_msec; |
| 335 | dprint(FD_TIME, "tmp=%llu, max_cycles_shift=%u\n", tmp, |
| 336 | max_cycles_shift); |
| 337 | while (tmp > 1) { |
| 338 | tmp >>= 1; |
| 339 | max_cycles_shift++; |
| 340 | dprint(FD_TIME, "tmp=%llu, max_cycles_shift=%u\n", tmp, max_cycles_shift); |
| 341 | } |
| 342 | /* |
| 343 | * if use use (1ULL << max_cycles_shift) * 1000 / cycles_per_msec |
| 344 | * here we will have a discontinuity every |
| 345 | * (1ULL << max_cycles_shift) cycles |
| 346 | */ |
| 347 | nsecs_for_max_cycles = ((1ULL << max_cycles_shift) * clock_mult) |
| 348 | >> clock_shift; |
| 349 | |
| 350 | /* Use a bitmask to calculate ticks % (1ULL << max_cycles_shift) */ |
| 351 | for (tmp = 0; tmp < max_cycles_shift; tmp++) |
| 352 | max_cycles_mask |= 1ULL << tmp; |
| 353 | |
| 354 | dprint(FD_TIME, "max_cycles_shift=%u, 2^max_cycles_shift=%llu, " |
| 355 | "nsecs_for_max_cycles=%llu, " |
| 356 | "max_cycles_mask=%016llx\n", |
| 357 | max_cycles_shift, (1ULL << max_cycles_shift), |
| 358 | nsecs_for_max_cycles, max_cycles_mask); |
| 359 | |
| 360 | cycles_start = get_cpu_clock(); |
| 361 | dprint(FD_TIME, "cycles_start=%llu\n", cycles_start); |
| 362 | return 0; |
| 363 | } |
| 364 | #else |
| 365 | static int calibrate_cpu_clock(void) |
| 366 | { |
| 367 | #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC |
| 368 | return 0; |
| 369 | #else |
| 370 | return 1; |
| 371 | #endif |
| 372 | } |
| 373 | #endif // ARCH_HAVE_CPU_CLOCK |
| 374 | |
| 375 | #ifndef CONFIG_TLS_THREAD |
| 376 | void fio_local_clock_init(int is_thread) |
| 377 | { |
| 378 | struct tv_valid *t; |
| 379 | |
| 380 | t = calloc(1, sizeof(*t)); |
| 381 | if (pthread_setspecific(tv_tls_key, t)) { |
| 382 | log_err("fio: can't set TLS key\n"); |
| 383 | assert(0); |
| 384 | } |
| 385 | } |
| 386 | |
| 387 | static void kill_tv_tls_key(void *data) |
| 388 | { |
| 389 | free(data); |
| 390 | } |
| 391 | #else |
| 392 | void fio_local_clock_init(int is_thread) |
| 393 | { |
| 394 | } |
| 395 | #endif |
| 396 | |
| 397 | void fio_clock_init(void) |
| 398 | { |
| 399 | if (fio_clock_source == fio_clock_source_inited) |
| 400 | return; |
| 401 | |
| 402 | #ifndef CONFIG_TLS_THREAD |
| 403 | if (pthread_key_create(&tv_tls_key, kill_tv_tls_key)) |
| 404 | log_err("fio: can't create TLS key\n"); |
| 405 | #endif |
| 406 | |
| 407 | fio_clock_source_inited = fio_clock_source; |
| 408 | |
| 409 | if (calibrate_cpu_clock()) |
| 410 | tsc_reliable = false; |
| 411 | |
| 412 | /* |
| 413 | * If the arch sets tsc_reliable != 0, then it must be good enough |
| 414 | * to use as THE clock source. For x86 CPUs, this means the TSC |
| 415 | * runs at a constant rate and is synced across CPU cores. |
| 416 | */ |
| 417 | if (tsc_reliable) { |
| 418 | if (!fio_clock_source_set && !fio_monotonic_clocktest(0)) |
| 419 | fio_clock_source = CS_CPUCLOCK; |
| 420 | } else if (fio_clock_source == CS_CPUCLOCK) |
| 421 | log_info("fio: clocksource=cpu may not be reliable\n"); |
| 422 | dprint(FD_TIME, "gettime: clocksource=%d\n", (int) fio_clock_source); |
| 423 | } |
| 424 | |
| 425 | uint64_t ntime_since(const struct timespec *s, const struct timespec *e) |
| 426 | { |
| 427 | int64_t sec, nsec; |
| 428 | |
| 429 | sec = e->tv_sec - s->tv_sec; |
| 430 | nsec = e->tv_nsec - s->tv_nsec; |
| 431 | if (sec > 0 && nsec < 0) { |
| 432 | sec--; |
| 433 | nsec += 1000000000LL; |
| 434 | } |
| 435 | |
| 436 | /* |
| 437 | * time warp bug on some kernels? |
| 438 | */ |
| 439 | if (sec < 0 || (sec == 0 && nsec < 0)) |
| 440 | return 0; |
| 441 | |
| 442 | return nsec + (sec * 1000000000LL); |
| 443 | } |
| 444 | |
| 445 | uint64_t ntime_since_now(const struct timespec *s) |
| 446 | { |
| 447 | struct timespec now; |
| 448 | |
| 449 | fio_gettime(&now, NULL); |
| 450 | return ntime_since(s, &now); |
| 451 | } |
| 452 | |
| 453 | uint64_t utime_since(const struct timespec *s, const struct timespec *e) |
| 454 | { |
| 455 | int64_t sec, usec; |
| 456 | |
| 457 | sec = e->tv_sec - s->tv_sec; |
| 458 | usec = (e->tv_nsec - s->tv_nsec) / 1000; |
| 459 | if (sec > 0 && usec < 0) { |
| 460 | sec--; |
| 461 | usec += 1000000; |
| 462 | } |
| 463 | |
| 464 | /* |
| 465 | * time warp bug on some kernels? |
| 466 | */ |
| 467 | if (sec < 0 || (sec == 0 && usec < 0)) |
| 468 | return 0; |
| 469 | |
| 470 | return usec + (sec * 1000000); |
| 471 | } |
| 472 | |
| 473 | uint64_t utime_since_now(const struct timespec *s) |
| 474 | { |
| 475 | struct timespec t; |
| 476 | #ifdef FIO_DEBUG_TIME |
| 477 | void *p = __builtin_return_address(0); |
| 478 | |
| 479 | fio_gettime(&t, p); |
| 480 | #else |
| 481 | fio_gettime(&t, NULL); |
| 482 | #endif |
| 483 | |
| 484 | return utime_since(s, &t); |
| 485 | } |
| 486 | |
| 487 | uint64_t mtime_since_tv(const struct timeval *s, const struct timeval *e) |
| 488 | { |
| 489 | int64_t sec, usec; |
| 490 | |
| 491 | sec = e->tv_sec - s->tv_sec; |
| 492 | usec = (e->tv_usec - s->tv_usec); |
| 493 | if (sec > 0 && usec < 0) { |
| 494 | sec--; |
| 495 | usec += 1000000; |
| 496 | } |
| 497 | |
| 498 | if (sec < 0 || (sec == 0 && usec < 0)) |
| 499 | return 0; |
| 500 | |
| 501 | sec *= 1000; |
| 502 | usec /= 1000; |
| 503 | return sec + usec; |
| 504 | } |
| 505 | |
| 506 | uint64_t mtime_since_now(const struct timespec *s) |
| 507 | { |
| 508 | struct timespec t; |
| 509 | #ifdef FIO_DEBUG_TIME |
| 510 | void *p = __builtin_return_address(0); |
| 511 | |
| 512 | fio_gettime(&t, p); |
| 513 | #else |
| 514 | fio_gettime(&t, NULL); |
| 515 | #endif |
| 516 | |
| 517 | return mtime_since(s, &t); |
| 518 | } |
| 519 | |
| 520 | uint64_t mtime_since(const struct timespec *s, const struct timespec *e) |
| 521 | { |
| 522 | int64_t sec, usec; |
| 523 | |
| 524 | sec = e->tv_sec - s->tv_sec; |
| 525 | usec = (e->tv_nsec - s->tv_nsec) / 1000; |
| 526 | if (sec > 0 && usec < 0) { |
| 527 | sec--; |
| 528 | usec += 1000000; |
| 529 | } |
| 530 | |
| 531 | if (sec < 0 || (sec == 0 && usec < 0)) |
| 532 | return 0; |
| 533 | |
| 534 | sec *= 1000; |
| 535 | usec /= 1000; |
| 536 | return sec + usec; |
| 537 | } |
| 538 | |
| 539 | uint64_t time_since_now(const struct timespec *s) |
| 540 | { |
| 541 | return mtime_since_now(s) / 1000; |
| 542 | } |
| 543 | |
| 544 | #if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) && \ |
| 545 | defined(CONFIG_SYNC_SYNC) && defined(CONFIG_CMP_SWAP) |
| 546 | |
| 547 | #define CLOCK_ENTRIES_DEBUG 100000 |
| 548 | #define CLOCK_ENTRIES_TEST 1000 |
| 549 | |
| 550 | struct clock_entry { |
| 551 | uint32_t seq; |
| 552 | uint32_t cpu; |
| 553 | uint64_t tsc; |
| 554 | }; |
| 555 | |
| 556 | struct clock_thread { |
| 557 | pthread_t thread; |
| 558 | int cpu; |
| 559 | int debug; |
| 560 | struct fio_sem lock; |
| 561 | unsigned long nr_entries; |
| 562 | uint32_t *seq; |
| 563 | struct clock_entry *entries; |
| 564 | }; |
| 565 | |
| 566 | static inline uint32_t atomic32_compare_and_swap(uint32_t *ptr, uint32_t old, |
| 567 | uint32_t new) |
| 568 | { |
| 569 | return __sync_val_compare_and_swap(ptr, old, new); |
| 570 | } |
| 571 | |
| 572 | static void *clock_thread_fn(void *data) |
| 573 | { |
| 574 | struct clock_thread *t = data; |
| 575 | struct clock_entry *c; |
| 576 | os_cpu_mask_t cpu_mask; |
| 577 | unsigned long long first; |
| 578 | int i; |
| 579 | |
| 580 | if (fio_cpuset_init(&cpu_mask)) { |
| 581 | int __err = errno; |
| 582 | |
| 583 | log_err("clock cpuset init failed: %s\n", strerror(__err)); |
| 584 | goto err_out; |
| 585 | } |
| 586 | |
| 587 | fio_cpu_set(&cpu_mask, t->cpu); |
| 588 | |
| 589 | if (fio_setaffinity(gettid(), cpu_mask) == -1) { |
| 590 | int __err = errno; |
| 591 | |
| 592 | log_err("clock setaffinity failed: %s\n", strerror(__err)); |
| 593 | goto err; |
| 594 | } |
| 595 | |
| 596 | fio_sem_down(&t->lock); |
| 597 | |
| 598 | first = get_cpu_clock(); |
| 599 | c = &t->entries[0]; |
| 600 | for (i = 0; i < t->nr_entries; i++, c++) { |
| 601 | uint32_t seq; |
| 602 | uint64_t tsc; |
| 603 | |
| 604 | c->cpu = t->cpu; |
| 605 | do { |
| 606 | seq = *t->seq; |
| 607 | if (seq == UINT_MAX) |
| 608 | break; |
| 609 | __sync_synchronize(); |
| 610 | tsc = get_cpu_clock(); |
| 611 | } while (seq != atomic32_compare_and_swap(t->seq, seq, seq + 1)); |
| 612 | |
| 613 | if (seq == UINT_MAX) |
| 614 | break; |
| 615 | |
| 616 | c->seq = seq; |
| 617 | c->tsc = tsc; |
| 618 | } |
| 619 | |
| 620 | if (t->debug) { |
| 621 | unsigned long long clocks; |
| 622 | |
| 623 | clocks = t->entries[i - 1].tsc - t->entries[0].tsc; |
| 624 | log_info("cs: cpu%3d: %llu clocks seen, first %llu\n", t->cpu, |
| 625 | clocks, first); |
| 626 | } |
| 627 | |
| 628 | /* |
| 629 | * The most common platform clock breakage is returning zero |
| 630 | * indefinitely. Check for that and return failure. |
| 631 | */ |
| 632 | if (i > 1 && !t->entries[i - 1].tsc && !t->entries[0].tsc) |
| 633 | goto err; |
| 634 | |
| 635 | fio_cpuset_exit(&cpu_mask); |
| 636 | return NULL; |
| 637 | err: |
| 638 | fio_cpuset_exit(&cpu_mask); |
| 639 | err_out: |
| 640 | return (void *) 1; |
| 641 | } |
| 642 | |
| 643 | static int clock_cmp(const void *p1, const void *p2) |
| 644 | { |
| 645 | const struct clock_entry *c1 = p1; |
| 646 | const struct clock_entry *c2 = p2; |
| 647 | |
| 648 | if (c1->seq == c2->seq) |
| 649 | log_err("cs: bug in atomic sequence!\n"); |
| 650 | |
| 651 | return c1->seq - c2->seq; |
| 652 | } |
| 653 | |
| 654 | int fio_monotonic_clocktest(int debug) |
| 655 | { |
| 656 | struct clock_thread *cthreads; |
| 657 | unsigned int nr_cpus = cpus_online(); |
| 658 | struct clock_entry *entries; |
| 659 | unsigned long nr_entries, tentries, failed = 0; |
| 660 | struct clock_entry *prev, *this; |
| 661 | uint32_t seq = 0; |
| 662 | unsigned int i; |
| 663 | |
| 664 | if (debug) { |
| 665 | log_info("cs: reliable_tsc: %s\n", tsc_reliable ? "yes" : "no"); |
| 666 | |
| 667 | #ifdef FIO_INC_DEBUG |
| 668 | fio_debug |= 1U << FD_TIME; |
| 669 | #endif |
| 670 | nr_entries = CLOCK_ENTRIES_DEBUG; |
| 671 | } else |
| 672 | nr_entries = CLOCK_ENTRIES_TEST; |
| 673 | |
| 674 | calibrate_cpu_clock(); |
| 675 | |
| 676 | if (debug) { |
| 677 | #ifdef FIO_INC_DEBUG |
| 678 | fio_debug &= ~(1U << FD_TIME); |
| 679 | #endif |
| 680 | } |
| 681 | |
| 682 | cthreads = malloc(nr_cpus * sizeof(struct clock_thread)); |
| 683 | tentries = nr_entries * nr_cpus; |
| 684 | entries = malloc(tentries * sizeof(struct clock_entry)); |
| 685 | |
| 686 | if (debug) |
| 687 | log_info("cs: Testing %u CPUs\n", nr_cpus); |
| 688 | |
| 689 | for (i = 0; i < nr_cpus; i++) { |
| 690 | struct clock_thread *t = &cthreads[i]; |
| 691 | |
| 692 | t->cpu = i; |
| 693 | t->debug = debug; |
| 694 | t->seq = &seq; |
| 695 | t->nr_entries = nr_entries; |
| 696 | t->entries = &entries[i * nr_entries]; |
| 697 | __fio_sem_init(&t->lock, FIO_SEM_LOCKED); |
| 698 | if (pthread_create(&t->thread, NULL, clock_thread_fn, t)) { |
| 699 | failed++; |
| 700 | nr_cpus = i; |
| 701 | break; |
| 702 | } |
| 703 | } |
| 704 | |
| 705 | for (i = 0; i < nr_cpus; i++) { |
| 706 | struct clock_thread *t = &cthreads[i]; |
| 707 | |
| 708 | fio_sem_up(&t->lock); |
| 709 | } |
| 710 | |
| 711 | for (i = 0; i < nr_cpus; i++) { |
| 712 | struct clock_thread *t = &cthreads[i]; |
| 713 | void *ret; |
| 714 | |
| 715 | pthread_join(t->thread, &ret); |
| 716 | if (ret) |
| 717 | failed++; |
| 718 | __fio_sem_remove(&t->lock); |
| 719 | } |
| 720 | free(cthreads); |
| 721 | |
| 722 | if (failed) { |
| 723 | if (debug) |
| 724 | log_err("Clocksource test: %lu threads failed\n", failed); |
| 725 | goto err; |
| 726 | } |
| 727 | |
| 728 | qsort(entries, tentries, sizeof(struct clock_entry), clock_cmp); |
| 729 | |
| 730 | /* silence silly gcc */ |
| 731 | prev = NULL; |
| 732 | for (failed = i = 0; i < tentries; i++) { |
| 733 | this = &entries[i]; |
| 734 | |
| 735 | if (!i) { |
| 736 | prev = this; |
| 737 | continue; |
| 738 | } |
| 739 | |
| 740 | if (prev->tsc > this->tsc) { |
| 741 | uint64_t diff = prev->tsc - this->tsc; |
| 742 | |
| 743 | if (!debug) { |
| 744 | failed++; |
| 745 | break; |
| 746 | } |
| 747 | |
| 748 | log_info("cs: CPU clock mismatch (diff=%llu):\n", |
| 749 | (unsigned long long) diff); |
| 750 | log_info("\t CPU%3u: TSC=%llu, SEQ=%u\n", prev->cpu, (unsigned long long) prev->tsc, prev->seq); |
| 751 | log_info("\t CPU%3u: TSC=%llu, SEQ=%u\n", this->cpu, (unsigned long long) this->tsc, this->seq); |
| 752 | failed++; |
| 753 | } |
| 754 | |
| 755 | prev = this; |
| 756 | } |
| 757 | |
| 758 | if (debug) { |
| 759 | if (failed) |
| 760 | log_info("cs: Failed: %lu\n", failed); |
| 761 | else |
| 762 | log_info("cs: Pass!\n"); |
| 763 | } |
| 764 | err: |
| 765 | free(entries); |
| 766 | return !!failed; |
| 767 | } |
| 768 | |
| 769 | #else /* defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) */ |
| 770 | |
| 771 | int fio_monotonic_clocktest(int debug) |
| 772 | { |
| 773 | if (debug) |
| 774 | log_info("cs: current platform does not support CPU clocks\n"); |
| 775 | return 1; |
| 776 | } |
| 777 | |
| 778 | #endif |