1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * bcache sysfs interfaces 4 * 5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> 6 * Copyright 2012 Google, Inc. 7 */ 8 9 #include "bcache.h" 10 #include "sysfs.h" 11 #include "btree.h" 12 #include "request.h" 13 #include "writeback.h" 14 #include "features.h" 15 16 #include <linux/blkdev.h> 17 #include <linux/sort.h> 18 #include <linux/sched/clock.h> 19 20 extern bool bcache_is_reboot; 21 22 /* Default is 0 ("writethrough") */ 23 static const char * const bch_cache_modes[] = { 24 "writethrough", 25 "writeback", 26 "writearound", 27 "none", 28 NULL 29 }; 30 31 static const char * const bch_reada_cache_policies[] = { 32 "all", 33 "meta-only", 34 NULL 35 }; 36 37 /* Default is 0 ("auto") */ 38 static const char * const bch_stop_on_failure_modes[] = { 39 "auto", 40 "always", 41 NULL 42 }; 43 44 static const char * const cache_replacement_policies[] = { 45 "lru", 46 "fifo", 47 "random", 48 NULL 49 }; 50 51 static const char * const error_actions[] = { 52 "unregister", 53 "panic", 54 NULL 55 }; 56 57 write_attribute(attach); 58 write_attribute(detach); 59 write_attribute(unregister); 60 write_attribute(stop); 61 write_attribute(clear_stats); 62 write_attribute(trigger_gc); 63 write_attribute(prune_cache); 64 write_attribute(flash_vol_create); 65 66 read_attribute(bucket_size); 67 read_attribute(block_size); 68 read_attribute(nbuckets); 69 read_attribute(tree_depth); 70 read_attribute(root_usage_percent); 71 read_attribute(priority_stats); 72 read_attribute(btree_cache_size); 73 read_attribute(btree_cache_max_chain); 74 read_attribute(cache_available_percent); 75 read_attribute(written); 76 read_attribute(btree_written); 77 read_attribute(metadata_written); 78 read_attribute(active_journal_entries); 79 read_attribute(backing_dev_name); 80 read_attribute(backing_dev_uuid); 81 82 sysfs_time_stats_attribute(btree_gc, sec, ms); 83 sysfs_time_stats_attribute(btree_split, sec, us); 84 sysfs_time_stats_attribute(btree_sort, ms, us); 85 sysfs_time_stats_attribute(btree_read, ms, us); 86 87 read_attribute(btree_nodes); 88 read_attribute(btree_used_percent); 89 read_attribute(average_key_size); 90 read_attribute(dirty_data); 91 read_attribute(bset_tree_stats); 92 read_attribute(feature_compat); 93 read_attribute(feature_ro_compat); 94 read_attribute(feature_incompat); 95 96 read_attribute(state); 97 read_attribute(cache_read_races); 98 read_attribute(reclaim); 99 read_attribute(reclaimed_journal_buckets); 100 read_attribute(flush_write); 101 read_attribute(writeback_keys_done); 102 read_attribute(writeback_keys_failed); 103 read_attribute(io_errors); 104 read_attribute(congested); 105 read_attribute(cutoff_writeback); 106 read_attribute(cutoff_writeback_sync); 107 rw_attribute(congested_read_threshold_us); 108 rw_attribute(congested_write_threshold_us); 109 110 rw_attribute(sequential_cutoff); 111 rw_attribute(data_csum); 112 rw_attribute(cache_mode); 113 rw_attribute(readahead_cache_policy); 114 rw_attribute(stop_when_cache_set_failed); 115 rw_attribute(writeback_metadata); 116 rw_attribute(writeback_running); 117 rw_attribute(writeback_percent); 118 rw_attribute(writeback_delay); 119 rw_attribute(writeback_rate); 120 rw_attribute(writeback_consider_fragment); 121 122 rw_attribute(writeback_rate_update_seconds); 123 rw_attribute(writeback_rate_i_term_inverse); 124 rw_attribute(writeback_rate_p_term_inverse); 125 rw_attribute(writeback_rate_fp_term_low); 126 rw_attribute(writeback_rate_fp_term_mid); 127 rw_attribute(writeback_rate_fp_term_high); 128 rw_attribute(writeback_rate_minimum); 129 read_attribute(writeback_rate_debug); 130 131 read_attribute(stripe_size); 132 read_attribute(partial_stripes_expensive); 133 134 rw_attribute(synchronous); 135 rw_attribute(journal_delay_ms); 136 rw_attribute(io_disable); 137 rw_attribute(discard); 138 rw_attribute(running); 139 rw_attribute(label); 140 rw_attribute(errors); 141 rw_attribute(io_error_limit); 142 rw_attribute(io_error_halflife); 143 rw_attribute(verify); 144 rw_attribute(bypass_torture_test); 145 rw_attribute(key_merging_disabled); 146 rw_attribute(gc_always_rewrite); 147 rw_attribute(expensive_debug_checks); 148 rw_attribute(cache_replacement_policy); 149 rw_attribute(btree_shrinker_disabled); 150 rw_attribute(copy_gc_enabled); 151 rw_attribute(idle_max_writeback_rate); 152 rw_attribute(gc_after_writeback); 153 rw_attribute(size); 154 155 static ssize_t bch_snprint_string_list(char *buf, 156 size_t size, 157 const char * const list[], 158 size_t selected) 159 { 160 char *out = buf; 161 size_t i; 162 163 for (i = 0; list[i]; i++) 164 out += scnprintf(out, buf + size - out, 165 i == selected ? "[%s] " : "%s ", list[i]); 166 167 out[-1] = '\n'; 168 return out - buf; 169 } 170 171 SHOW(__bch_cached_dev) 172 { 173 struct cached_dev *dc = container_of(kobj, struct cached_dev, 174 disk.kobj); 175 char const *states[] = { "no cache", "clean", "dirty", "inconsistent" }; 176 int wb = dc->writeback_running; 177 178 #define var(stat) (dc->stat) 179 180 if (attr == &sysfs_cache_mode) 181 return bch_snprint_string_list(buf, PAGE_SIZE, 182 bch_cache_modes, 183 BDEV_CACHE_MODE(&dc->sb)); 184 185 if (attr == &sysfs_readahead_cache_policy) 186 return bch_snprint_string_list(buf, PAGE_SIZE, 187 bch_reada_cache_policies, 188 dc->cache_readahead_policy); 189 190 if (attr == &sysfs_stop_when_cache_set_failed) 191 return bch_snprint_string_list(buf, PAGE_SIZE, 192 bch_stop_on_failure_modes, 193 dc->stop_when_cache_set_failed); 194 195 196 sysfs_printf(data_csum, "%i", dc->disk.data_csum); 197 var_printf(verify, "%i"); 198 var_printf(bypass_torture_test, "%i"); 199 var_printf(writeback_metadata, "%i"); 200 var_printf(writeback_running, "%i"); 201 var_printf(writeback_consider_fragment, "%i"); 202 var_print(writeback_delay); 203 var_print(writeback_percent); 204 sysfs_hprint(writeback_rate, 205 wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 : 0); 206 sysfs_printf(io_errors, "%i", atomic_read(&dc->io_errors)); 207 sysfs_printf(io_error_limit, "%i", dc->error_limit); 208 sysfs_printf(io_disable, "%i", dc->io_disable); 209 var_print(writeback_rate_update_seconds); 210 var_print(writeback_rate_i_term_inverse); 211 var_print(writeback_rate_p_term_inverse); 212 var_print(writeback_rate_fp_term_low); 213 var_print(writeback_rate_fp_term_mid); 214 var_print(writeback_rate_fp_term_high); 215 var_print(writeback_rate_minimum); 216 217 if (attr == &sysfs_writeback_rate_debug) { 218 char rate[20]; 219 char dirty[20]; 220 char target[20]; 221 char proportional[20]; 222 char integral[20]; 223 char change[20]; 224 s64 next_io; 225 226 /* 227 * Except for dirty and target, other values should 228 * be 0 if writeback is not running. 229 */ 230 bch_hprint(rate, 231 wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 232 : 0); 233 bch_hprint(dirty, bcache_dev_sectors_dirty(&dc->disk) << 9); 234 bch_hprint(target, dc->writeback_rate_target << 9); 235 bch_hprint(proportional, 236 wb ? dc->writeback_rate_proportional << 9 : 0); 237 bch_hprint(integral, 238 wb ? dc->writeback_rate_integral_scaled << 9 : 0); 239 bch_hprint(change, wb ? dc->writeback_rate_change << 9 : 0); 240 next_io = wb ? div64_s64(dc->writeback_rate.next-local_clock(), 241 NSEC_PER_MSEC) : 0; 242 243 return sprintf(buf, 244 "rate:\t\t%s/sec\n" 245 "dirty:\t\t%s\n" 246 "target:\t\t%s\n" 247 "proportional:\t%s\n" 248 "integral:\t%s\n" 249 "change:\t\t%s/sec\n" 250 "next io:\t%llims\n", 251 rate, dirty, target, proportional, 252 integral, change, next_io); 253 } 254 255 sysfs_hprint(dirty_data, 256 bcache_dev_sectors_dirty(&dc->disk) << 9); 257 258 sysfs_hprint(stripe_size, ((uint64_t)dc->disk.stripe_size) << 9); 259 var_printf(partial_stripes_expensive, "%u"); 260 261 var_hprint(sequential_cutoff); 262 263 sysfs_print(running, atomic_read(&dc->running)); 264 sysfs_print(state, states[BDEV_STATE(&dc->sb)]); 265 266 if (attr == &sysfs_label) { 267 memcpy(buf, dc->sb.label, SB_LABEL_SIZE); 268 buf[SB_LABEL_SIZE + 1] = '\0'; 269 strcat(buf, "\n"); 270 return strlen(buf); 271 } 272 273 if (attr == &sysfs_backing_dev_name) { 274 snprintf(buf, BDEVNAME_SIZE + 1, "%pg", dc->bdev); 275 strcat(buf, "\n"); 276 return strlen(buf); 277 } 278 279 if (attr == &sysfs_backing_dev_uuid) { 280 /* convert binary uuid into 36-byte string plus '\0' */ 281 snprintf(buf, 36+1, "%pU", dc->sb.uuid); 282 strcat(buf, "\n"); 283 return strlen(buf); 284 } 285 286 #undef var 287 return 0; 288 } 289 SHOW_LOCKED(bch_cached_dev) 290 291 STORE(__cached_dev) 292 { 293 struct cached_dev *dc = container_of(kobj, struct cached_dev, 294 disk.kobj); 295 ssize_t v; 296 struct cache_set *c; 297 struct kobj_uevent_env *env; 298 299 /* no user space access if system is rebooting */ 300 if (bcache_is_reboot) 301 return -EBUSY; 302 303 #define d_strtoul(var) sysfs_strtoul(var, dc->var) 304 #define d_strtoul_nonzero(var) sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX) 305 #define d_strtoi_h(var) sysfs_hatoi(var, dc->var) 306 307 sysfs_strtoul(data_csum, dc->disk.data_csum); 308 d_strtoul(verify); 309 sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test); 310 sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata); 311 sysfs_strtoul_bool(writeback_running, dc->writeback_running); 312 sysfs_strtoul_bool(writeback_consider_fragment, dc->writeback_consider_fragment); 313 sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX); 314 315 sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 316 0, bch_cutoff_writeback); 317 318 if (attr == &sysfs_writeback_rate) { 319 ssize_t ret; 320 long int v = atomic_long_read(&dc->writeback_rate.rate); 321 322 ret = strtoul_safe_clamp(buf, v, 1, INT_MAX); 323 324 if (!ret) { 325 atomic_long_set(&dc->writeback_rate.rate, v); 326 ret = size; 327 } 328 329 return ret; 330 } 331 332 sysfs_strtoul_clamp(writeback_rate_update_seconds, 333 dc->writeback_rate_update_seconds, 334 1, WRITEBACK_RATE_UPDATE_SECS_MAX); 335 sysfs_strtoul_clamp(writeback_rate_i_term_inverse, 336 dc->writeback_rate_i_term_inverse, 337 1, UINT_MAX); 338 sysfs_strtoul_clamp(writeback_rate_p_term_inverse, 339 dc->writeback_rate_p_term_inverse, 340 1, UINT_MAX); 341 sysfs_strtoul_clamp(writeback_rate_fp_term_low, 342 dc->writeback_rate_fp_term_low, 343 1, dc->writeback_rate_fp_term_mid - 1); 344 sysfs_strtoul_clamp(writeback_rate_fp_term_mid, 345 dc->writeback_rate_fp_term_mid, 346 dc->writeback_rate_fp_term_low + 1, 347 dc->writeback_rate_fp_term_high - 1); 348 sysfs_strtoul_clamp(writeback_rate_fp_term_high, 349 dc->writeback_rate_fp_term_high, 350 dc->writeback_rate_fp_term_mid + 1, UINT_MAX); 351 sysfs_strtoul_clamp(writeback_rate_minimum, 352 dc->writeback_rate_minimum, 353 1, UINT_MAX); 354 355 sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX); 356 357 if (attr == &sysfs_io_disable) { 358 int v = strtoul_or_return(buf); 359 360 dc->io_disable = v ? 1 : 0; 361 } 362 363 sysfs_strtoul_clamp(sequential_cutoff, 364 dc->sequential_cutoff, 365 0, UINT_MAX); 366 367 if (attr == &sysfs_clear_stats) 368 bch_cache_accounting_clear(&dc->accounting); 369 370 if (attr == &sysfs_running && 371 strtoul_or_return(buf)) { 372 v = bch_cached_dev_run(dc); 373 if (v) 374 return v; 375 } 376 377 if (attr == &sysfs_cache_mode) { 378 v = __sysfs_match_string(bch_cache_modes, -1, buf); 379 if (v < 0) 380 return v; 381 382 if ((unsigned int) v != BDEV_CACHE_MODE(&dc->sb)) { 383 SET_BDEV_CACHE_MODE(&dc->sb, v); 384 bch_write_bdev_super(dc, NULL); 385 } 386 } 387 388 if (attr == &sysfs_readahead_cache_policy) { 389 v = __sysfs_match_string(bch_reada_cache_policies, -1, buf); 390 if (v < 0) 391 return v; 392 393 if ((unsigned int) v != dc->cache_readahead_policy) 394 dc->cache_readahead_policy = v; 395 } 396 397 if (attr == &sysfs_stop_when_cache_set_failed) { 398 v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf); 399 if (v < 0) 400 return v; 401 402 dc->stop_when_cache_set_failed = v; 403 } 404 405 if (attr == &sysfs_label) { 406 if (size > SB_LABEL_SIZE) 407 return -EINVAL; 408 memcpy(dc->sb.label, buf, size); 409 if (size < SB_LABEL_SIZE) 410 dc->sb.label[size] = '\0'; 411 if (size && dc->sb.label[size - 1] == '\n') 412 dc->sb.label[size - 1] = '\0'; 413 bch_write_bdev_super(dc, NULL); 414 if (dc->disk.c) { 415 memcpy(dc->disk.c->uuids[dc->disk.id].label, 416 buf, SB_LABEL_SIZE); 417 bch_uuid_write(dc->disk.c); 418 } 419 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); 420 if (!env) 421 return -ENOMEM; 422 add_uevent_var(env, "DRIVER=bcache"); 423 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid); 424 add_uevent_var(env, "CACHED_LABEL=%s", buf); 425 kobject_uevent_env(&disk_to_dev(dc->disk.disk)->kobj, 426 KOBJ_CHANGE, 427 env->envp); 428 kfree(env); 429 } 430 431 if (attr == &sysfs_attach) { 432 uint8_t set_uuid[16]; 433 434 if (bch_parse_uuid(buf, set_uuid) < 16) 435 return -EINVAL; 436 437 v = -ENOENT; 438 list_for_each_entry(c, &bch_cache_sets, list) { 439 v = bch_cached_dev_attach(dc, c, set_uuid); 440 if (!v) 441 return size; 442 } 443 if (v == -ENOENT) 444 pr_err("Can't attach %s: cache set not found\n", buf); 445 return v; 446 } 447 448 if (attr == &sysfs_detach && dc->disk.c) 449 bch_cached_dev_detach(dc); 450 451 if (attr == &sysfs_stop) 452 bcache_device_stop(&dc->disk); 453 454 return size; 455 } 456 457 STORE(bch_cached_dev) 458 { 459 struct cached_dev *dc = container_of(kobj, struct cached_dev, 460 disk.kobj); 461 462 /* no user space access if system is rebooting */ 463 if (bcache_is_reboot) 464 return -EBUSY; 465 466 mutex_lock(&bch_register_lock); 467 size = __cached_dev_store(kobj, attr, buf, size); 468 469 if (attr == &sysfs_writeback_running) { 470 /* dc->writeback_running changed in __cached_dev_store() */ 471 if (IS_ERR_OR_NULL(dc->writeback_thread)) { 472 /* 473 * reject setting it to 1 via sysfs if writeback 474 * kthread is not created yet. 475 */ 476 if (dc->writeback_running) { 477 dc->writeback_running = false; 478 pr_err("%s: failed to run non-existent writeback thread\n", 479 dc->disk.disk->disk_name); 480 } 481 } else 482 /* 483 * writeback kthread will check if dc->writeback_running 484 * is true or false. 485 */ 486 bch_writeback_queue(dc); 487 } 488 489 /* 490 * Only set BCACHE_DEV_WB_RUNNING when cached device attached to 491 * a cache set, otherwise it doesn't make sense. 492 */ 493 if (attr == &sysfs_writeback_percent) 494 if ((dc->disk.c != NULL) && 495 (!test_and_set_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags))) 496 schedule_delayed_work(&dc->writeback_rate_update, 497 dc->writeback_rate_update_seconds * HZ); 498 499 mutex_unlock(&bch_register_lock); 500 return size; 501 } 502 503 static struct attribute *bch_cached_dev_attrs[] = { 504 &sysfs_attach, 505 &sysfs_detach, 506 &sysfs_stop, 507 #if 0 508 &sysfs_data_csum, 509 #endif 510 &sysfs_cache_mode, 511 &sysfs_readahead_cache_policy, 512 &sysfs_stop_when_cache_set_failed, 513 &sysfs_writeback_metadata, 514 &sysfs_writeback_running, 515 &sysfs_writeback_delay, 516 &sysfs_writeback_percent, 517 &sysfs_writeback_rate, 518 &sysfs_writeback_consider_fragment, 519 &sysfs_writeback_rate_update_seconds, 520 &sysfs_writeback_rate_i_term_inverse, 521 &sysfs_writeback_rate_p_term_inverse, 522 &sysfs_writeback_rate_fp_term_low, 523 &sysfs_writeback_rate_fp_term_mid, 524 &sysfs_writeback_rate_fp_term_high, 525 &sysfs_writeback_rate_minimum, 526 &sysfs_writeback_rate_debug, 527 &sysfs_io_errors, 528 &sysfs_io_error_limit, 529 &sysfs_io_disable, 530 &sysfs_dirty_data, 531 &sysfs_stripe_size, 532 &sysfs_partial_stripes_expensive, 533 &sysfs_sequential_cutoff, 534 &sysfs_clear_stats, 535 &sysfs_running, 536 &sysfs_state, 537 &sysfs_label, 538 #ifdef CONFIG_BCACHE_DEBUG 539 &sysfs_verify, 540 &sysfs_bypass_torture_test, 541 #endif 542 &sysfs_backing_dev_name, 543 &sysfs_backing_dev_uuid, 544 NULL 545 }; 546 ATTRIBUTE_GROUPS(bch_cached_dev); 547 KTYPE(bch_cached_dev); 548 549 SHOW(bch_flash_dev) 550 { 551 struct bcache_device *d = container_of(kobj, struct bcache_device, 552 kobj); 553 struct uuid_entry *u = &d->c->uuids[d->id]; 554 555 sysfs_printf(data_csum, "%i", d->data_csum); 556 sysfs_hprint(size, u->sectors << 9); 557 558 if (attr == &sysfs_label) { 559 memcpy(buf, u->label, SB_LABEL_SIZE); 560 buf[SB_LABEL_SIZE + 1] = '\0'; 561 strcat(buf, "\n"); 562 return strlen(buf); 563 } 564 565 return 0; 566 } 567 568 STORE(__bch_flash_dev) 569 { 570 struct bcache_device *d = container_of(kobj, struct bcache_device, 571 kobj); 572 struct uuid_entry *u = &d->c->uuids[d->id]; 573 574 /* no user space access if system is rebooting */ 575 if (bcache_is_reboot) 576 return -EBUSY; 577 578 sysfs_strtoul(data_csum, d->data_csum); 579 580 if (attr == &sysfs_size) { 581 uint64_t v; 582 583 strtoi_h_or_return(buf, v); 584 585 u->sectors = v >> 9; 586 bch_uuid_write(d->c); 587 set_capacity(d->disk, u->sectors); 588 } 589 590 if (attr == &sysfs_label) { 591 memcpy(u->label, buf, SB_LABEL_SIZE); 592 bch_uuid_write(d->c); 593 } 594 595 if (attr == &sysfs_unregister) { 596 set_bit(BCACHE_DEV_DETACHING, &d->flags); 597 bcache_device_stop(d); 598 } 599 600 return size; 601 } 602 STORE_LOCKED(bch_flash_dev) 603 604 static struct attribute *bch_flash_dev_attrs[] = { 605 &sysfs_unregister, 606 #if 0 607 &sysfs_data_csum, 608 #endif 609 &sysfs_label, 610 &sysfs_size, 611 NULL 612 }; 613 ATTRIBUTE_GROUPS(bch_flash_dev); 614 KTYPE(bch_flash_dev); 615 616 struct bset_stats_op { 617 struct btree_op op; 618 size_t nodes; 619 struct bset_stats stats; 620 }; 621 622 static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b) 623 { 624 struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op); 625 626 op->nodes++; 627 bch_btree_keys_stats(&b->keys, &op->stats); 628 629 return MAP_CONTINUE; 630 } 631 632 static int bch_bset_print_stats(struct cache_set *c, char *buf) 633 { 634 struct bset_stats_op op; 635 int ret; 636 637 memset(&op, 0, sizeof(op)); 638 bch_btree_op_init(&op.op, -1); 639 640 ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats); 641 if (ret < 0) 642 return ret; 643 644 return snprintf(buf, PAGE_SIZE, 645 "btree nodes: %zu\n" 646 "written sets: %zu\n" 647 "unwritten sets: %zu\n" 648 "written key bytes: %zu\n" 649 "unwritten key bytes: %zu\n" 650 "floats: %zu\n" 651 "failed: %zu\n", 652 op.nodes, 653 op.stats.sets_written, op.stats.sets_unwritten, 654 op.stats.bytes_written, op.stats.bytes_unwritten, 655 op.stats.floats, op.stats.failed); 656 } 657 658 static unsigned int bch_root_usage(struct cache_set *c) 659 { 660 unsigned int bytes = 0; 661 struct bkey *k; 662 struct btree *b; 663 struct btree_iter iter; 664 665 goto lock_root; 666 667 do { 668 rw_unlock(false, b); 669 lock_root: 670 b = c->root; 671 rw_lock(false, b, b->level); 672 } while (b != c->root); 673 674 for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad) 675 bytes += bkey_bytes(k); 676 677 rw_unlock(false, b); 678 679 return (bytes * 100) / btree_bytes(c); 680 } 681 682 static size_t bch_cache_size(struct cache_set *c) 683 { 684 size_t ret = 0; 685 struct btree *b; 686 687 mutex_lock(&c->bucket_lock); 688 list_for_each_entry(b, &c->btree_cache, list) 689 ret += 1 << (b->keys.page_order + PAGE_SHIFT); 690 691 mutex_unlock(&c->bucket_lock); 692 return ret; 693 } 694 695 static unsigned int bch_cache_max_chain(struct cache_set *c) 696 { 697 unsigned int ret = 0; 698 struct hlist_head *h; 699 700 mutex_lock(&c->bucket_lock); 701 702 for (h = c->bucket_hash; 703 h < c->bucket_hash + (1 << BUCKET_HASH_BITS); 704 h++) { 705 unsigned int i = 0; 706 struct hlist_node *p; 707 708 hlist_for_each(p, h) 709 i++; 710 711 ret = max(ret, i); 712 } 713 714 mutex_unlock(&c->bucket_lock); 715 return ret; 716 } 717 718 static unsigned int bch_btree_used(struct cache_set *c) 719 { 720 return div64_u64(c->gc_stats.key_bytes * 100, 721 (c->gc_stats.nodes ?: 1) * btree_bytes(c)); 722 } 723 724 static unsigned int bch_average_key_size(struct cache_set *c) 725 { 726 return c->gc_stats.nkeys 727 ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys) 728 : 0; 729 } 730 731 SHOW(__bch_cache_set) 732 { 733 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 734 735 sysfs_print(synchronous, CACHE_SYNC(&c->cache->sb)); 736 sysfs_print(journal_delay_ms, c->journal_delay_ms); 737 sysfs_hprint(bucket_size, bucket_bytes(c->cache)); 738 sysfs_hprint(block_size, block_bytes(c->cache)); 739 sysfs_print(tree_depth, c->root->level); 740 sysfs_print(root_usage_percent, bch_root_usage(c)); 741 742 sysfs_hprint(btree_cache_size, bch_cache_size(c)); 743 sysfs_print(btree_cache_max_chain, bch_cache_max_chain(c)); 744 sysfs_print(cache_available_percent, 100 - c->gc_stats.in_use); 745 746 sysfs_print_time_stats(&c->btree_gc_time, btree_gc, sec, ms); 747 sysfs_print_time_stats(&c->btree_split_time, btree_split, sec, us); 748 sysfs_print_time_stats(&c->sort.time, btree_sort, ms, us); 749 sysfs_print_time_stats(&c->btree_read_time, btree_read, ms, us); 750 751 sysfs_print(btree_used_percent, bch_btree_used(c)); 752 sysfs_print(btree_nodes, c->gc_stats.nodes); 753 sysfs_hprint(average_key_size, bch_average_key_size(c)); 754 755 sysfs_print(cache_read_races, 756 atomic_long_read(&c->cache_read_races)); 757 758 sysfs_print(reclaim, 759 atomic_long_read(&c->reclaim)); 760 761 sysfs_print(reclaimed_journal_buckets, 762 atomic_long_read(&c->reclaimed_journal_buckets)); 763 764 sysfs_print(flush_write, 765 atomic_long_read(&c->flush_write)); 766 767 sysfs_print(writeback_keys_done, 768 atomic_long_read(&c->writeback_keys_done)); 769 sysfs_print(writeback_keys_failed, 770 atomic_long_read(&c->writeback_keys_failed)); 771 772 if (attr == &sysfs_errors) 773 return bch_snprint_string_list(buf, PAGE_SIZE, error_actions, 774 c->on_error); 775 776 /* See count_io_errors for why 88 */ 777 sysfs_print(io_error_halflife, c->error_decay * 88); 778 sysfs_print(io_error_limit, c->error_limit); 779 780 sysfs_hprint(congested, 781 ((uint64_t) bch_get_congested(c)) << 9); 782 sysfs_print(congested_read_threshold_us, 783 c->congested_read_threshold_us); 784 sysfs_print(congested_write_threshold_us, 785 c->congested_write_threshold_us); 786 787 sysfs_print(cutoff_writeback, bch_cutoff_writeback); 788 sysfs_print(cutoff_writeback_sync, bch_cutoff_writeback_sync); 789 790 sysfs_print(active_journal_entries, fifo_used(&c->journal.pin)); 791 sysfs_printf(verify, "%i", c->verify); 792 sysfs_printf(key_merging_disabled, "%i", c->key_merging_disabled); 793 sysfs_printf(expensive_debug_checks, 794 "%i", c->expensive_debug_checks); 795 sysfs_printf(gc_always_rewrite, "%i", c->gc_always_rewrite); 796 sysfs_printf(btree_shrinker_disabled, "%i", c->shrinker_disabled); 797 sysfs_printf(copy_gc_enabled, "%i", c->copy_gc_enabled); 798 sysfs_printf(idle_max_writeback_rate, "%i", 799 c->idle_max_writeback_rate_enabled); 800 sysfs_printf(gc_after_writeback, "%i", c->gc_after_writeback); 801 sysfs_printf(io_disable, "%i", 802 test_bit(CACHE_SET_IO_DISABLE, &c->flags)); 803 804 if (attr == &sysfs_bset_tree_stats) 805 return bch_bset_print_stats(c, buf); 806 807 if (attr == &sysfs_feature_compat) 808 return bch_print_cache_set_feature_compat(c, buf, PAGE_SIZE); 809 if (attr == &sysfs_feature_ro_compat) 810 return bch_print_cache_set_feature_ro_compat(c, buf, PAGE_SIZE); 811 if (attr == &sysfs_feature_incompat) 812 return bch_print_cache_set_feature_incompat(c, buf, PAGE_SIZE); 813 814 return 0; 815 } 816 SHOW_LOCKED(bch_cache_set) 817 818 STORE(__bch_cache_set) 819 { 820 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 821 ssize_t v; 822 823 /* no user space access if system is rebooting */ 824 if (bcache_is_reboot) 825 return -EBUSY; 826 827 if (attr == &sysfs_unregister) 828 bch_cache_set_unregister(c); 829 830 if (attr == &sysfs_stop) 831 bch_cache_set_stop(c); 832 833 if (attr == &sysfs_synchronous) { 834 bool sync = strtoul_or_return(buf); 835 836 if (sync != CACHE_SYNC(&c->cache->sb)) { 837 SET_CACHE_SYNC(&c->cache->sb, sync); 838 bcache_write_super(c); 839 } 840 } 841 842 if (attr == &sysfs_flash_vol_create) { 843 int r; 844 uint64_t v; 845 846 strtoi_h_or_return(buf, v); 847 848 r = bch_flash_dev_create(c, v); 849 if (r) 850 return r; 851 } 852 853 if (attr == &sysfs_clear_stats) { 854 atomic_long_set(&c->writeback_keys_done, 0); 855 atomic_long_set(&c->writeback_keys_failed, 0); 856 857 memset(&c->gc_stats, 0, sizeof(struct gc_stat)); 858 bch_cache_accounting_clear(&c->accounting); 859 } 860 861 if (attr == &sysfs_trigger_gc) 862 force_wake_up_gc(c); 863 864 if (attr == &sysfs_prune_cache) { 865 struct shrink_control sc; 866 867 sc.gfp_mask = GFP_KERNEL; 868 sc.nr_to_scan = strtoul_or_return(buf); 869 if (c->shrink) 870 c->shrink->scan_objects(c->shrink, &sc); 871 } 872 873 sysfs_strtoul_clamp(congested_read_threshold_us, 874 c->congested_read_threshold_us, 875 0, UINT_MAX); 876 sysfs_strtoul_clamp(congested_write_threshold_us, 877 c->congested_write_threshold_us, 878 0, UINT_MAX); 879 880 if (attr == &sysfs_errors) { 881 v = __sysfs_match_string(error_actions, -1, buf); 882 if (v < 0) 883 return v; 884 885 c->on_error = v; 886 } 887 888 sysfs_strtoul_clamp(io_error_limit, c->error_limit, 0, UINT_MAX); 889 890 /* See count_io_errors() for why 88 */ 891 if (attr == &sysfs_io_error_halflife) { 892 unsigned long v = 0; 893 ssize_t ret; 894 895 ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX); 896 if (!ret) { 897 c->error_decay = v / 88; 898 return size; 899 } 900 return ret; 901 } 902 903 if (attr == &sysfs_io_disable) { 904 v = strtoul_or_return(buf); 905 if (v) { 906 if (test_and_set_bit(CACHE_SET_IO_DISABLE, 907 &c->flags)) 908 pr_warn("CACHE_SET_IO_DISABLE already set\n"); 909 } else { 910 if (!test_and_clear_bit(CACHE_SET_IO_DISABLE, 911 &c->flags)) 912 pr_warn("CACHE_SET_IO_DISABLE already cleared\n"); 913 } 914 } 915 916 sysfs_strtoul_clamp(journal_delay_ms, 917 c->journal_delay_ms, 918 0, USHRT_MAX); 919 sysfs_strtoul_bool(verify, c->verify); 920 sysfs_strtoul_bool(key_merging_disabled, c->key_merging_disabled); 921 sysfs_strtoul(expensive_debug_checks, c->expensive_debug_checks); 922 sysfs_strtoul_bool(gc_always_rewrite, c->gc_always_rewrite); 923 sysfs_strtoul_bool(btree_shrinker_disabled, c->shrinker_disabled); 924 sysfs_strtoul_bool(copy_gc_enabled, c->copy_gc_enabled); 925 sysfs_strtoul_bool(idle_max_writeback_rate, 926 c->idle_max_writeback_rate_enabled); 927 928 /* 929 * write gc_after_writeback here may overwrite an already set 930 * BCH_DO_AUTO_GC, it doesn't matter because this flag will be 931 * set in next chance. 932 */ 933 sysfs_strtoul_clamp(gc_after_writeback, c->gc_after_writeback, 0, 1); 934 935 return size; 936 } 937 STORE_LOCKED(bch_cache_set) 938 939 SHOW(bch_cache_set_internal) 940 { 941 struct cache_set *c = container_of(kobj, struct cache_set, internal); 942 943 return bch_cache_set_show(&c->kobj, attr, buf); 944 } 945 946 STORE(bch_cache_set_internal) 947 { 948 struct cache_set *c = container_of(kobj, struct cache_set, internal); 949 950 /* no user space access if system is rebooting */ 951 if (bcache_is_reboot) 952 return -EBUSY; 953 954 return bch_cache_set_store(&c->kobj, attr, buf, size); 955 } 956 957 static void bch_cache_set_internal_release(struct kobject *k) 958 { 959 } 960 961 static struct attribute *bch_cache_set_attrs[] = { 962 &sysfs_unregister, 963 &sysfs_stop, 964 &sysfs_synchronous, 965 &sysfs_journal_delay_ms, 966 &sysfs_flash_vol_create, 967 968 &sysfs_bucket_size, 969 &sysfs_block_size, 970 &sysfs_tree_depth, 971 &sysfs_root_usage_percent, 972 &sysfs_btree_cache_size, 973 &sysfs_cache_available_percent, 974 975 &sysfs_average_key_size, 976 977 &sysfs_errors, 978 &sysfs_io_error_limit, 979 &sysfs_io_error_halflife, 980 &sysfs_congested, 981 &sysfs_congested_read_threshold_us, 982 &sysfs_congested_write_threshold_us, 983 &sysfs_clear_stats, 984 NULL 985 }; 986 ATTRIBUTE_GROUPS(bch_cache_set); 987 KTYPE(bch_cache_set); 988 989 static struct attribute *bch_cache_set_internal_attrs[] = { 990 &sysfs_active_journal_entries, 991 992 sysfs_time_stats_attribute_list(btree_gc, sec, ms) 993 sysfs_time_stats_attribute_list(btree_split, sec, us) 994 sysfs_time_stats_attribute_list(btree_sort, ms, us) 995 sysfs_time_stats_attribute_list(btree_read, ms, us) 996 997 &sysfs_btree_nodes, 998 &sysfs_btree_used_percent, 999 &sysfs_btree_cache_max_chain, 1000 1001 &sysfs_bset_tree_stats, 1002 &sysfs_cache_read_races, 1003 &sysfs_reclaim, 1004 &sysfs_reclaimed_journal_buckets, 1005 &sysfs_flush_write, 1006 &sysfs_writeback_keys_done, 1007 &sysfs_writeback_keys_failed, 1008 1009 &sysfs_trigger_gc, 1010 &sysfs_prune_cache, 1011 #ifdef CONFIG_BCACHE_DEBUG 1012 &sysfs_verify, 1013 &sysfs_key_merging_disabled, 1014 &sysfs_expensive_debug_checks, 1015 #endif 1016 &sysfs_gc_always_rewrite, 1017 &sysfs_btree_shrinker_disabled, 1018 &sysfs_copy_gc_enabled, 1019 &sysfs_idle_max_writeback_rate, 1020 &sysfs_gc_after_writeback, 1021 &sysfs_io_disable, 1022 &sysfs_cutoff_writeback, 1023 &sysfs_cutoff_writeback_sync, 1024 &sysfs_feature_compat, 1025 &sysfs_feature_ro_compat, 1026 &sysfs_feature_incompat, 1027 NULL 1028 }; 1029 ATTRIBUTE_GROUPS(bch_cache_set_internal); 1030 KTYPE(bch_cache_set_internal); 1031 1032 static int __bch_cache_cmp(const void *l, const void *r) 1033 { 1034 cond_resched(); 1035 return *((uint16_t *)r) - *((uint16_t *)l); 1036 } 1037 1038 SHOW(__bch_cache) 1039 { 1040 struct cache *ca = container_of(kobj, struct cache, kobj); 1041 1042 sysfs_hprint(bucket_size, bucket_bytes(ca)); 1043 sysfs_hprint(block_size, block_bytes(ca)); 1044 sysfs_print(nbuckets, ca->sb.nbuckets); 1045 sysfs_print(discard, ca->discard); 1046 sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9); 1047 sysfs_hprint(btree_written, 1048 atomic_long_read(&ca->btree_sectors_written) << 9); 1049 sysfs_hprint(metadata_written, 1050 (atomic_long_read(&ca->meta_sectors_written) + 1051 atomic_long_read(&ca->btree_sectors_written)) << 9); 1052 1053 sysfs_print(io_errors, 1054 atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT); 1055 1056 if (attr == &sysfs_cache_replacement_policy) 1057 return bch_snprint_string_list(buf, PAGE_SIZE, 1058 cache_replacement_policies, 1059 CACHE_REPLACEMENT(&ca->sb)); 1060 1061 if (attr == &sysfs_priority_stats) { 1062 struct bucket *b; 1063 size_t n = ca->sb.nbuckets, i; 1064 size_t unused = 0, available = 0, dirty = 0, meta = 0; 1065 uint64_t sum = 0; 1066 /* Compute 31 quantiles */ 1067 uint16_t q[31], *p, *cached; 1068 ssize_t ret; 1069 1070 cached = p = vmalloc(array_size(sizeof(uint16_t), 1071 ca->sb.nbuckets)); 1072 if (!p) 1073 return -ENOMEM; 1074 1075 mutex_lock(&ca->set->bucket_lock); 1076 for_each_bucket(b, ca) { 1077 if (!GC_SECTORS_USED(b)) 1078 unused++; 1079 if (GC_MARK(b) == GC_MARK_RECLAIMABLE) 1080 available++; 1081 if (GC_MARK(b) == GC_MARK_DIRTY) 1082 dirty++; 1083 if (GC_MARK(b) == GC_MARK_METADATA) 1084 meta++; 1085 } 1086 1087 for (i = ca->sb.first_bucket; i < n; i++) 1088 p[i] = ca->buckets[i].prio; 1089 mutex_unlock(&ca->set->bucket_lock); 1090 1091 sort(p, n, sizeof(uint16_t), __bch_cache_cmp, NULL); 1092 1093 while (n && 1094 !cached[n - 1]) 1095 --n; 1096 1097 while (cached < p + n && 1098 *cached == BTREE_PRIO) { 1099 cached++; 1100 n--; 1101 } 1102 1103 for (i = 0; i < n; i++) 1104 sum += INITIAL_PRIO - cached[i]; 1105 1106 if (n) 1107 sum = div64_u64(sum, n); 1108 1109 for (i = 0; i < ARRAY_SIZE(q); i++) 1110 q[i] = INITIAL_PRIO - cached[n * (i + 1) / 1111 (ARRAY_SIZE(q) + 1)]; 1112 1113 vfree(p); 1114 1115 ret = sysfs_emit(buf, 1116 "Unused: %zu%%\n" 1117 "Clean: %zu%%\n" 1118 "Dirty: %zu%%\n" 1119 "Metadata: %zu%%\n" 1120 "Average: %llu\n" 1121 "Sectors per Q: %zu\n" 1122 "Quantiles: [", 1123 unused * 100 / (size_t) ca->sb.nbuckets, 1124 available * 100 / (size_t) ca->sb.nbuckets, 1125 dirty * 100 / (size_t) ca->sb.nbuckets, 1126 meta * 100 / (size_t) ca->sb.nbuckets, sum, 1127 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1)); 1128 1129 for (i = 0; i < ARRAY_SIZE(q); i++) 1130 ret += sysfs_emit_at(buf, ret, "%u ", q[i]); 1131 ret--; 1132 1133 ret += sysfs_emit_at(buf, ret, "]\n"); 1134 1135 return ret; 1136 } 1137 1138 return 0; 1139 } 1140 SHOW_LOCKED(bch_cache) 1141 1142 STORE(__bch_cache) 1143 { 1144 struct cache *ca = container_of(kobj, struct cache, kobj); 1145 ssize_t v; 1146 1147 /* no user space access if system is rebooting */ 1148 if (bcache_is_reboot) 1149 return -EBUSY; 1150 1151 if (attr == &sysfs_discard) { 1152 bool v = strtoul_or_return(buf); 1153 1154 if (bdev_max_discard_sectors(ca->bdev)) 1155 ca->discard = v; 1156 1157 if (v != CACHE_DISCARD(&ca->sb)) { 1158 SET_CACHE_DISCARD(&ca->sb, v); 1159 bcache_write_super(ca->set); 1160 } 1161 } 1162 1163 if (attr == &sysfs_cache_replacement_policy) { 1164 v = __sysfs_match_string(cache_replacement_policies, -1, buf); 1165 if (v < 0) 1166 return v; 1167 1168 if ((unsigned int) v != CACHE_REPLACEMENT(&ca->sb)) { 1169 mutex_lock(&ca->set->bucket_lock); 1170 SET_CACHE_REPLACEMENT(&ca->sb, v); 1171 mutex_unlock(&ca->set->bucket_lock); 1172 1173 bcache_write_super(ca->set); 1174 } 1175 } 1176 1177 if (attr == &sysfs_clear_stats) { 1178 atomic_long_set(&ca->sectors_written, 0); 1179 atomic_long_set(&ca->btree_sectors_written, 0); 1180 atomic_long_set(&ca->meta_sectors_written, 0); 1181 atomic_set(&ca->io_count, 0); 1182 atomic_set(&ca->io_errors, 0); 1183 } 1184 1185 return size; 1186 } 1187 STORE_LOCKED(bch_cache) 1188 1189 static struct attribute *bch_cache_attrs[] = { 1190 &sysfs_bucket_size, 1191 &sysfs_block_size, 1192 &sysfs_nbuckets, 1193 &sysfs_priority_stats, 1194 &sysfs_discard, 1195 &sysfs_written, 1196 &sysfs_btree_written, 1197 &sysfs_metadata_written, 1198 &sysfs_io_errors, 1199 &sysfs_clear_stats, 1200 &sysfs_cache_replacement_policy, 1201 NULL 1202 }; 1203 ATTRIBUTE_GROUPS(bch_cache); 1204 KTYPE(bch_cache); 1205