1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * random utiility code, for bcache but in theory not specific to bcache 4 * 5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> 6 * Copyright 2012 Google, Inc. 7 */ 8 9 #include <linux/bio.h> 10 #include <linux/blkdev.h> 11 #include <linux/console.h> 12 #include <linux/ctype.h> 13 #include <linux/debugfs.h> 14 #include <linux/freezer.h> 15 #include <linux/kthread.h> 16 #include <linux/log2.h> 17 #include <linux/math64.h> 18 #include <linux/percpu.h> 19 #include <linux/preempt.h> 20 #include <linux/random.h> 21 #include <linux/seq_file.h> 22 #include <linux/string.h> 23 #include <linux/types.h> 24 #include <linux/sched/clock.h> 25 26 #include "eytzinger.h" 27 #include "mean_and_variance.h" 28 #include "util.h" 29 30 static const char si_units[] = "?kMGTPEZY"; 31 32 /* string_get_size units: */ 33 static const char *const units_2[] = { 34 "B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB" 35 }; 36 static const char *const units_10[] = { 37 "B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB" 38 }; 39 40 static int parse_u64(const char *cp, u64 *res) 41 { 42 const char *start = cp; 43 u64 v = 0; 44 45 if (!isdigit(*cp)) 46 return -EINVAL; 47 48 do { 49 if (v > U64_MAX / 10) 50 return -ERANGE; 51 v *= 10; 52 if (v > U64_MAX - (*cp - '0')) 53 return -ERANGE; 54 v += *cp - '0'; 55 cp++; 56 } while (isdigit(*cp)); 57 58 *res = v; 59 return cp - start; 60 } 61 62 static int bch2_pow(u64 n, u64 p, u64 *res) 63 { 64 *res = 1; 65 66 while (p--) { 67 if (*res > div_u64(U64_MAX, n)) 68 return -ERANGE; 69 *res *= n; 70 } 71 return 0; 72 } 73 74 static int parse_unit_suffix(const char *cp, u64 *res) 75 { 76 const char *start = cp; 77 u64 base = 1024; 78 unsigned u; 79 int ret; 80 81 if (*cp == ' ') 82 cp++; 83 84 for (u = 1; u < strlen(si_units); u++) 85 if (*cp == si_units[u]) { 86 cp++; 87 goto got_unit; 88 } 89 90 for (u = 0; u < ARRAY_SIZE(units_2); u++) 91 if (!strncmp(cp, units_2[u], strlen(units_2[u]))) { 92 cp += strlen(units_2[u]); 93 goto got_unit; 94 } 95 96 for (u = 0; u < ARRAY_SIZE(units_10); u++) 97 if (!strncmp(cp, units_10[u], strlen(units_10[u]))) { 98 cp += strlen(units_10[u]); 99 base = 1000; 100 goto got_unit; 101 } 102 103 *res = 1; 104 return 0; 105 got_unit: 106 ret = bch2_pow(base, u, res); 107 if (ret) 108 return ret; 109 110 return cp - start; 111 } 112 113 #define parse_or_ret(cp, _f) \ 114 do { \ 115 int _ret = _f; \ 116 if (_ret < 0) \ 117 return _ret; \ 118 cp += _ret; \ 119 } while (0) 120 121 static int __bch2_strtou64_h(const char *cp, u64 *res) 122 { 123 const char *start = cp; 124 u64 v = 0, b, f_n = 0, f_d = 1; 125 int ret; 126 127 parse_or_ret(cp, parse_u64(cp, &v)); 128 129 if (*cp == '.') { 130 cp++; 131 ret = parse_u64(cp, &f_n); 132 if (ret < 0) 133 return ret; 134 cp += ret; 135 136 ret = bch2_pow(10, ret, &f_d); 137 if (ret) 138 return ret; 139 } 140 141 parse_or_ret(cp, parse_unit_suffix(cp, &b)); 142 143 if (v > div_u64(U64_MAX, b)) 144 return -ERANGE; 145 v *= b; 146 147 if (f_n > div_u64(U64_MAX, b)) 148 return -ERANGE; 149 150 f_n = div_u64(f_n * b, f_d); 151 if (v + f_n < v) 152 return -ERANGE; 153 v += f_n; 154 155 *res = v; 156 return cp - start; 157 } 158 159 static int __bch2_strtoh(const char *cp, u64 *res, 160 u64 t_max, bool t_signed) 161 { 162 bool positive = *cp != '-'; 163 u64 v = 0; 164 165 if (*cp == '+' || *cp == '-') 166 cp++; 167 168 parse_or_ret(cp, __bch2_strtou64_h(cp, &v)); 169 170 if (*cp == '\n') 171 cp++; 172 if (*cp) 173 return -EINVAL; 174 175 if (positive) { 176 if (v > t_max) 177 return -ERANGE; 178 } else { 179 if (v && !t_signed) 180 return -ERANGE; 181 182 if (v > t_max + 1) 183 return -ERANGE; 184 v = -v; 185 } 186 187 *res = v; 188 return 0; 189 } 190 191 #define STRTO_H(name, type) \ 192 int bch2_ ## name ## _h(const char *cp, type *res) \ 193 { \ 194 u64 v = 0; \ 195 int ret = __bch2_strtoh(cp, &v, ANYSINT_MAX(type), \ 196 ANYSINT_MAX(type) != ((type) ~0ULL)); \ 197 *res = v; \ 198 return ret; \ 199 } 200 201 STRTO_H(strtoint, int) 202 STRTO_H(strtouint, unsigned int) 203 STRTO_H(strtoll, long long) 204 STRTO_H(strtoull, unsigned long long) 205 STRTO_H(strtou64, u64) 206 207 u64 bch2_read_flag_list(char *opt, const char * const list[]) 208 { 209 u64 ret = 0; 210 char *p, *s, *d = kstrdup(opt, GFP_KERNEL); 211 212 if (!d) 213 return -ENOMEM; 214 215 s = strim(d); 216 217 while ((p = strsep(&s, ","))) { 218 int flag = match_string(list, -1, p); 219 220 if (flag < 0) { 221 ret = -1; 222 break; 223 } 224 225 ret |= 1 << flag; 226 } 227 228 kfree(d); 229 230 return ret; 231 } 232 233 bool bch2_is_zero(const void *_p, size_t n) 234 { 235 const char *p = _p; 236 size_t i; 237 238 for (i = 0; i < n; i++) 239 if (p[i]) 240 return false; 241 return true; 242 } 243 244 void bch2_prt_u64_base2_nbits(struct printbuf *out, u64 v, unsigned nr_bits) 245 { 246 while (nr_bits) 247 prt_char(out, '0' + ((v >> --nr_bits) & 1)); 248 } 249 250 void bch2_prt_u64_base2(struct printbuf *out, u64 v) 251 { 252 bch2_prt_u64_base2_nbits(out, v, fls64(v) ?: 1); 253 } 254 255 void bch2_print_string_as_lines(const char *prefix, const char *lines) 256 { 257 const char *p; 258 259 if (!lines) { 260 printk("%s (null)\n", prefix); 261 return; 262 } 263 264 console_lock(); 265 while (1) { 266 p = strchrnul(lines, '\n'); 267 printk("%s%.*s\n", prefix, (int) (p - lines), lines); 268 if (!*p) 269 break; 270 lines = p + 1; 271 } 272 console_unlock(); 273 } 274 275 int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *task, unsigned skipnr, 276 gfp_t gfp) 277 { 278 #ifdef CONFIG_STACKTRACE 279 unsigned nr_entries = 0; 280 281 stack->nr = 0; 282 int ret = darray_make_room_gfp(stack, 32, gfp); 283 if (ret) 284 return ret; 285 286 if (!down_read_trylock(&task->signal->exec_update_lock)) 287 return -1; 288 289 do { 290 nr_entries = stack_trace_save_tsk(task, stack->data, stack->size, skipnr + 1); 291 } while (nr_entries == stack->size && 292 !(ret = darray_make_room_gfp(stack, stack->size * 2, gfp))); 293 294 stack->nr = nr_entries; 295 up_read(&task->signal->exec_update_lock); 296 297 return ret; 298 #else 299 return 0; 300 #endif 301 } 302 303 void bch2_prt_backtrace(struct printbuf *out, bch_stacktrace *stack) 304 { 305 darray_for_each(*stack, i) { 306 prt_printf(out, "[<0>] %pB", (void *) *i); 307 prt_newline(out); 308 } 309 } 310 311 int bch2_prt_task_backtrace(struct printbuf *out, struct task_struct *task, unsigned skipnr, gfp_t gfp) 312 { 313 bch_stacktrace stack = { 0 }; 314 int ret = bch2_save_backtrace(&stack, task, skipnr + 1, gfp); 315 316 bch2_prt_backtrace(out, &stack); 317 darray_exit(&stack); 318 return ret; 319 } 320 321 #ifndef __KERNEL__ 322 #include <time.h> 323 void bch2_prt_datetime(struct printbuf *out, time64_t sec) 324 { 325 time_t t = sec; 326 char buf[64]; 327 ctime_r(&t, buf); 328 strim(buf); 329 prt_str(out, buf); 330 } 331 #else 332 void bch2_prt_datetime(struct printbuf *out, time64_t sec) 333 { 334 char buf[64]; 335 snprintf(buf, sizeof(buf), "%ptT", &sec); 336 prt_u64(out, sec); 337 } 338 #endif 339 340 void bch2_pr_time_units(struct printbuf *out, u64 ns) 341 { 342 const struct time_unit *u = bch2_pick_time_units(ns); 343 344 prt_printf(out, "%llu %s", div_u64(ns, u->nsecs), u->name); 345 } 346 347 static void bch2_pr_time_units_aligned(struct printbuf *out, u64 ns) 348 { 349 const struct time_unit *u = bch2_pick_time_units(ns); 350 351 prt_printf(out, "%llu \r%s", div64_u64(ns, u->nsecs), u->name); 352 } 353 354 static inline void pr_name_and_units(struct printbuf *out, const char *name, u64 ns) 355 { 356 prt_printf(out, "%s\t", name); 357 bch2_pr_time_units_aligned(out, ns); 358 prt_newline(out); 359 } 360 361 #define TABSTOP_SIZE 12 362 363 void bch2_time_stats_to_text(struct printbuf *out, struct bch2_time_stats *stats) 364 { 365 struct quantiles *quantiles = time_stats_to_quantiles(stats); 366 s64 f_mean = 0, d_mean = 0; 367 u64 f_stddev = 0, d_stddev = 0; 368 369 if (stats->buffer) { 370 int cpu; 371 372 spin_lock_irq(&stats->lock); 373 for_each_possible_cpu(cpu) 374 __bch2_time_stats_clear_buffer(stats, per_cpu_ptr(stats->buffer, cpu)); 375 spin_unlock_irq(&stats->lock); 376 } 377 378 /* 379 * avoid divide by zero 380 */ 381 if (stats->freq_stats.n) { 382 f_mean = mean_and_variance_get_mean(stats->freq_stats); 383 f_stddev = mean_and_variance_get_stddev(stats->freq_stats); 384 d_mean = mean_and_variance_get_mean(stats->duration_stats); 385 d_stddev = mean_and_variance_get_stddev(stats->duration_stats); 386 } 387 388 printbuf_tabstop_push(out, out->indent + TABSTOP_SIZE); 389 prt_printf(out, "count:\t%llu\n", stats->duration_stats.n); 390 printbuf_tabstop_pop(out); 391 392 printbuf_tabstops_reset(out); 393 394 printbuf_tabstop_push(out, out->indent + 20); 395 printbuf_tabstop_push(out, TABSTOP_SIZE + 2); 396 printbuf_tabstop_push(out, 0); 397 printbuf_tabstop_push(out, TABSTOP_SIZE + 2); 398 399 prt_printf(out, "\tsince mount\r\trecent\r\n"); 400 prt_printf(out, "recent"); 401 402 printbuf_tabstops_reset(out); 403 printbuf_tabstop_push(out, out->indent + 20); 404 printbuf_tabstop_push(out, TABSTOP_SIZE); 405 printbuf_tabstop_push(out, 2); 406 printbuf_tabstop_push(out, TABSTOP_SIZE); 407 408 prt_printf(out, "duration of events\n"); 409 printbuf_indent_add(out, 2); 410 411 pr_name_and_units(out, "min:", stats->min_duration); 412 pr_name_and_units(out, "max:", stats->max_duration); 413 pr_name_and_units(out, "total:", stats->total_duration); 414 415 prt_printf(out, "mean:\t"); 416 bch2_pr_time_units_aligned(out, d_mean); 417 prt_tab(out); 418 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->duration_stats_weighted, TIME_STATS_MV_WEIGHT)); 419 prt_newline(out); 420 421 prt_printf(out, "stddev:\t"); 422 bch2_pr_time_units_aligned(out, d_stddev); 423 prt_tab(out); 424 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->duration_stats_weighted, TIME_STATS_MV_WEIGHT)); 425 426 printbuf_indent_sub(out, 2); 427 prt_newline(out); 428 429 prt_printf(out, "time between events\n"); 430 printbuf_indent_add(out, 2); 431 432 pr_name_and_units(out, "min:", stats->min_freq); 433 pr_name_and_units(out, "max:", stats->max_freq); 434 435 prt_printf(out, "mean:\t"); 436 bch2_pr_time_units_aligned(out, f_mean); 437 prt_tab(out); 438 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_mean(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT)); 439 prt_newline(out); 440 441 prt_printf(out, "stddev:\t"); 442 bch2_pr_time_units_aligned(out, f_stddev); 443 prt_tab(out); 444 bch2_pr_time_units_aligned(out, mean_and_variance_weighted_get_stddev(stats->freq_stats_weighted, TIME_STATS_MV_WEIGHT)); 445 446 printbuf_indent_sub(out, 2); 447 prt_newline(out); 448 449 printbuf_tabstops_reset(out); 450 451 if (quantiles) { 452 int i = eytzinger0_first(NR_QUANTILES); 453 const struct time_unit *u = 454 bch2_pick_time_units(quantiles->entries[i].m); 455 u64 last_q = 0; 456 457 prt_printf(out, "quantiles (%s):\t", u->name); 458 eytzinger0_for_each(i, NR_QUANTILES) { 459 bool is_last = eytzinger0_next(i, NR_QUANTILES) == -1; 460 461 u64 q = max(quantiles->entries[i].m, last_q); 462 prt_printf(out, "%llu ", div_u64(q, u->nsecs)); 463 if (is_last) 464 prt_newline(out); 465 last_q = q; 466 } 467 } 468 } 469 470 /* ratelimit: */ 471 472 /** 473 * bch2_ratelimit_delay() - return how long to delay until the next time to do 474 * some work 475 * @d: the struct bch_ratelimit to update 476 * Returns: the amount of time to delay by, in jiffies 477 */ 478 u64 bch2_ratelimit_delay(struct bch_ratelimit *d) 479 { 480 u64 now = local_clock(); 481 482 return time_after64(d->next, now) 483 ? nsecs_to_jiffies(d->next - now) 484 : 0; 485 } 486 487 /** 488 * bch2_ratelimit_increment() - increment @d by the amount of work done 489 * @d: the struct bch_ratelimit to update 490 * @done: the amount of work done, in arbitrary units 491 */ 492 void bch2_ratelimit_increment(struct bch_ratelimit *d, u64 done) 493 { 494 u64 now = local_clock(); 495 496 d->next += div_u64(done * NSEC_PER_SEC, d->rate); 497 498 if (time_before64(now + NSEC_PER_SEC, d->next)) 499 d->next = now + NSEC_PER_SEC; 500 501 if (time_after64(now - NSEC_PER_SEC * 2, d->next)) 502 d->next = now - NSEC_PER_SEC * 2; 503 } 504 505 /* pd controller: */ 506 507 /* 508 * Updates pd_controller. Attempts to scale inputed values to units per second. 509 * @target: desired value 510 * @actual: current value 511 * 512 * @sign: 1 or -1; 1 if increasing the rate makes actual go up, -1 if increasing 513 * it makes actual go down. 514 */ 515 void bch2_pd_controller_update(struct bch_pd_controller *pd, 516 s64 target, s64 actual, int sign) 517 { 518 s64 proportional, derivative, change; 519 520 unsigned long seconds_since_update = (jiffies - pd->last_update) / HZ; 521 522 if (seconds_since_update == 0) 523 return; 524 525 pd->last_update = jiffies; 526 527 proportional = actual - target; 528 proportional *= seconds_since_update; 529 proportional = div_s64(proportional, pd->p_term_inverse); 530 531 derivative = actual - pd->last_actual; 532 derivative = div_s64(derivative, seconds_since_update); 533 derivative = ewma_add(pd->smoothed_derivative, derivative, 534 (pd->d_term / seconds_since_update) ?: 1); 535 derivative = derivative * pd->d_term; 536 derivative = div_s64(derivative, pd->p_term_inverse); 537 538 change = proportional + derivative; 539 540 /* Don't increase rate if not keeping up */ 541 if (change > 0 && 542 pd->backpressure && 543 time_after64(local_clock(), 544 pd->rate.next + NSEC_PER_MSEC)) 545 change = 0; 546 547 change *= (sign * -1); 548 549 pd->rate.rate = clamp_t(s64, (s64) pd->rate.rate + change, 550 1, UINT_MAX); 551 552 pd->last_actual = actual; 553 pd->last_derivative = derivative; 554 pd->last_proportional = proportional; 555 pd->last_change = change; 556 pd->last_target = target; 557 } 558 559 void bch2_pd_controller_init(struct bch_pd_controller *pd) 560 { 561 pd->rate.rate = 1024; 562 pd->last_update = jiffies; 563 pd->p_term_inverse = 6000; 564 pd->d_term = 30; 565 pd->d_smooth = pd->d_term; 566 pd->backpressure = 1; 567 } 568 569 void bch2_pd_controller_debug_to_text(struct printbuf *out, struct bch_pd_controller *pd) 570 { 571 if (!out->nr_tabstops) 572 printbuf_tabstop_push(out, 20); 573 574 prt_printf(out, "rate:\t"); 575 prt_human_readable_s64(out, pd->rate.rate); 576 prt_newline(out); 577 578 prt_printf(out, "target:\t"); 579 prt_human_readable_u64(out, pd->last_target); 580 prt_newline(out); 581 582 prt_printf(out, "actual:\t"); 583 prt_human_readable_u64(out, pd->last_actual); 584 prt_newline(out); 585 586 prt_printf(out, "proportional:\t"); 587 prt_human_readable_s64(out, pd->last_proportional); 588 prt_newline(out); 589 590 prt_printf(out, "derivative:\t"); 591 prt_human_readable_s64(out, pd->last_derivative); 592 prt_newline(out); 593 594 prt_printf(out, "change:\t"); 595 prt_human_readable_s64(out, pd->last_change); 596 prt_newline(out); 597 598 prt_printf(out, "next io:\t%llims\n", div64_s64(pd->rate.next - local_clock(), NSEC_PER_MSEC)); 599 } 600 601 /* misc: */ 602 603 void bch2_bio_map(struct bio *bio, void *base, size_t size) 604 { 605 while (size) { 606 struct page *page = is_vmalloc_addr(base) 607 ? vmalloc_to_page(base) 608 : virt_to_page(base); 609 unsigned offset = offset_in_page(base); 610 unsigned len = min_t(size_t, PAGE_SIZE - offset, size); 611 612 BUG_ON(!bio_add_page(bio, page, len, offset)); 613 size -= len; 614 base += len; 615 } 616 } 617 618 int bch2_bio_alloc_pages(struct bio *bio, size_t size, gfp_t gfp_mask) 619 { 620 while (size) { 621 struct page *page = alloc_pages(gfp_mask, 0); 622 unsigned len = min_t(size_t, PAGE_SIZE, size); 623 624 if (!page) 625 return -ENOMEM; 626 627 if (unlikely(!bio_add_page(bio, page, len, 0))) { 628 __free_page(page); 629 break; 630 } 631 632 size -= len; 633 } 634 635 return 0; 636 } 637 638 size_t bch2_rand_range(size_t max) 639 { 640 size_t rand; 641 642 if (!max) 643 return 0; 644 645 do { 646 rand = get_random_long(); 647 rand &= roundup_pow_of_two(max) - 1; 648 } while (rand >= max); 649 650 return rand; 651 } 652 653 void memcpy_to_bio(struct bio *dst, struct bvec_iter dst_iter, const void *src) 654 { 655 struct bio_vec bv; 656 struct bvec_iter iter; 657 658 __bio_for_each_segment(bv, dst, iter, dst_iter) { 659 void *dstp = kmap_local_page(bv.bv_page); 660 661 memcpy(dstp + bv.bv_offset, src, bv.bv_len); 662 kunmap_local(dstp); 663 664 src += bv.bv_len; 665 } 666 } 667 668 void memcpy_from_bio(void *dst, struct bio *src, struct bvec_iter src_iter) 669 { 670 struct bio_vec bv; 671 struct bvec_iter iter; 672 673 __bio_for_each_segment(bv, src, iter, src_iter) { 674 void *srcp = kmap_local_page(bv.bv_page); 675 676 memcpy(dst, srcp + bv.bv_offset, bv.bv_len); 677 kunmap_local(srcp); 678 679 dst += bv.bv_len; 680 } 681 } 682 683 #if 0 684 void eytzinger1_test(void) 685 { 686 unsigned inorder, eytz, size; 687 688 pr_info("1 based eytzinger test:"); 689 690 for (size = 2; 691 size < 65536; 692 size++) { 693 unsigned extra = eytzinger1_extra(size); 694 695 if (!(size % 4096)) 696 pr_info("tree size %u", size); 697 698 BUG_ON(eytzinger1_prev(0, size) != eytzinger1_last(size)); 699 BUG_ON(eytzinger1_next(0, size) != eytzinger1_first(size)); 700 701 BUG_ON(eytzinger1_prev(eytzinger1_first(size), size) != 0); 702 BUG_ON(eytzinger1_next(eytzinger1_last(size), size) != 0); 703 704 inorder = 1; 705 eytzinger1_for_each(eytz, size) { 706 BUG_ON(__inorder_to_eytzinger1(inorder, size, extra) != eytz); 707 BUG_ON(__eytzinger1_to_inorder(eytz, size, extra) != inorder); 708 BUG_ON(eytz != eytzinger1_last(size) && 709 eytzinger1_prev(eytzinger1_next(eytz, size), size) != eytz); 710 711 inorder++; 712 } 713 } 714 } 715 716 void eytzinger0_test(void) 717 { 718 719 unsigned inorder, eytz, size; 720 721 pr_info("0 based eytzinger test:"); 722 723 for (size = 1; 724 size < 65536; 725 size++) { 726 unsigned extra = eytzinger0_extra(size); 727 728 if (!(size % 4096)) 729 pr_info("tree size %u", size); 730 731 BUG_ON(eytzinger0_prev(-1, size) != eytzinger0_last(size)); 732 BUG_ON(eytzinger0_next(-1, size) != eytzinger0_first(size)); 733 734 BUG_ON(eytzinger0_prev(eytzinger0_first(size), size) != -1); 735 BUG_ON(eytzinger0_next(eytzinger0_last(size), size) != -1); 736 737 inorder = 0; 738 eytzinger0_for_each(eytz, size) { 739 BUG_ON(__inorder_to_eytzinger0(inorder, size, extra) != eytz); 740 BUG_ON(__eytzinger0_to_inorder(eytz, size, extra) != inorder); 741 BUG_ON(eytz != eytzinger0_last(size) && 742 eytzinger0_prev(eytzinger0_next(eytz, size), size) != eytz); 743 744 inorder++; 745 } 746 } 747 } 748 749 static inline int cmp_u16(const void *_l, const void *_r, size_t size) 750 { 751 const u16 *l = _l, *r = _r; 752 753 return (*l > *r) - (*r - *l); 754 } 755 756 static void eytzinger0_find_test_val(u16 *test_array, unsigned nr, u16 search) 757 { 758 int i, c1 = -1, c2 = -1; 759 ssize_t r; 760 761 r = eytzinger0_find_le(test_array, nr, 762 sizeof(test_array[0]), 763 cmp_u16, &search); 764 if (r >= 0) 765 c1 = test_array[r]; 766 767 for (i = 0; i < nr; i++) 768 if (test_array[i] <= search && test_array[i] > c2) 769 c2 = test_array[i]; 770 771 if (c1 != c2) { 772 eytzinger0_for_each(i, nr) 773 pr_info("[%3u] = %12u", i, test_array[i]); 774 pr_info("find_le(%2u) -> [%2zi] = %2i should be %2i", 775 i, r, c1, c2); 776 } 777 } 778 779 void eytzinger0_find_test(void) 780 { 781 unsigned i, nr, allocated = 1 << 12; 782 u16 *test_array = kmalloc_array(allocated, sizeof(test_array[0]), GFP_KERNEL); 783 784 for (nr = 1; nr < allocated; nr++) { 785 pr_info("testing %u elems", nr); 786 787 get_random_bytes(test_array, nr * sizeof(test_array[0])); 788 eytzinger0_sort(test_array, nr, sizeof(test_array[0]), cmp_u16, NULL); 789 790 /* verify array is sorted correctly: */ 791 eytzinger0_for_each(i, nr) 792 BUG_ON(i != eytzinger0_last(nr) && 793 test_array[i] > test_array[eytzinger0_next(i, nr)]); 794 795 for (i = 0; i < U16_MAX; i += 1 << 12) 796 eytzinger0_find_test_val(test_array, nr, i); 797 798 for (i = 0; i < nr; i++) { 799 eytzinger0_find_test_val(test_array, nr, test_array[i] - 1); 800 eytzinger0_find_test_val(test_array, nr, test_array[i]); 801 eytzinger0_find_test_val(test_array, nr, test_array[i] + 1); 802 } 803 } 804 805 kfree(test_array); 806 } 807 #endif 808 809 /* 810 * Accumulate percpu counters onto one cpu's copy - only valid when access 811 * against any percpu counter is guarded against 812 */ 813 u64 *bch2_acc_percpu_u64s(u64 __percpu *p, unsigned nr) 814 { 815 u64 *ret; 816 int cpu; 817 818 /* access to pcpu vars has to be blocked by other locking */ 819 preempt_disable(); 820 ret = this_cpu_ptr(p); 821 preempt_enable(); 822 823 for_each_possible_cpu(cpu) { 824 u64 *i = per_cpu_ptr(p, cpu); 825 826 if (i != ret) { 827 acc_u64s(ret, i, nr); 828 memset(i, 0, nr * sizeof(u64)); 829 } 830 } 831 832 return ret; 833 } 834 835 void bch2_darray_str_exit(darray_str *d) 836 { 837 darray_for_each(*d, i) 838 kfree(*i); 839 darray_exit(d); 840 } 841 842 int bch2_split_devs(const char *_dev_name, darray_str *ret) 843 { 844 darray_init(ret); 845 846 char *dev_name, *s, *orig; 847 848 dev_name = orig = kstrdup(_dev_name, GFP_KERNEL); 849 if (!dev_name) 850 return -ENOMEM; 851 852 while ((s = strsep(&dev_name, ":"))) { 853 char *p = kstrdup(s, GFP_KERNEL); 854 if (!p) 855 goto err; 856 857 if (darray_push(ret, p)) { 858 kfree(p); 859 goto err; 860 } 861 } 862 863 kfree(orig); 864 return 0; 865 err: 866 bch2_darray_str_exit(ret); 867 kfree(orig); 868 return -ENOMEM; 869 } 870