1 /* 2 * bcache sysfs interfaces 3 * 4 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> 5 * Copyright 2012 Google, Inc. 6 */ 7 8 #include "bcache.h" 9 #include "sysfs.h" 10 #include "btree.h" 11 #include "request.h" 12 #include "writeback.h" 13 14 #include <linux/blkdev.h> 15 #include <linux/sort.h> 16 17 static const char * const cache_replacement_policies[] = { 18 "lru", 19 "fifo", 20 "random", 21 NULL 22 }; 23 24 write_attribute(attach); 25 write_attribute(detach); 26 write_attribute(unregister); 27 write_attribute(stop); 28 write_attribute(clear_stats); 29 write_attribute(trigger_gc); 30 write_attribute(prune_cache); 31 write_attribute(flash_vol_create); 32 33 read_attribute(bucket_size); 34 read_attribute(block_size); 35 read_attribute(nbuckets); 36 read_attribute(tree_depth); 37 read_attribute(root_usage_percent); 38 read_attribute(priority_stats); 39 read_attribute(btree_cache_size); 40 read_attribute(btree_cache_max_chain); 41 read_attribute(cache_available_percent); 42 read_attribute(written); 43 read_attribute(btree_written); 44 read_attribute(metadata_written); 45 read_attribute(active_journal_entries); 46 47 sysfs_time_stats_attribute(btree_gc, sec, ms); 48 sysfs_time_stats_attribute(btree_split, sec, us); 49 sysfs_time_stats_attribute(btree_sort, ms, us); 50 sysfs_time_stats_attribute(btree_read, ms, us); 51 sysfs_time_stats_attribute(try_harder, ms, us); 52 53 read_attribute(btree_nodes); 54 read_attribute(btree_used_percent); 55 read_attribute(average_key_size); 56 read_attribute(dirty_data); 57 read_attribute(bset_tree_stats); 58 59 read_attribute(state); 60 read_attribute(cache_read_races); 61 read_attribute(writeback_keys_done); 62 read_attribute(writeback_keys_failed); 63 read_attribute(io_errors); 64 read_attribute(congested); 65 rw_attribute(congested_read_threshold_us); 66 rw_attribute(congested_write_threshold_us); 67 68 rw_attribute(sequential_cutoff); 69 rw_attribute(sequential_merge); 70 rw_attribute(data_csum); 71 rw_attribute(cache_mode); 72 rw_attribute(writeback_metadata); 73 rw_attribute(writeback_running); 74 rw_attribute(writeback_percent); 75 rw_attribute(writeback_delay); 76 rw_attribute(writeback_rate); 77 78 rw_attribute(writeback_rate_update_seconds); 79 rw_attribute(writeback_rate_d_term); 80 rw_attribute(writeback_rate_p_term_inverse); 81 rw_attribute(writeback_rate_d_smooth); 82 read_attribute(writeback_rate_debug); 83 84 read_attribute(stripe_size); 85 read_attribute(partial_stripes_expensive); 86 87 rw_attribute(synchronous); 88 rw_attribute(journal_delay_ms); 89 rw_attribute(discard); 90 rw_attribute(running); 91 rw_attribute(label); 92 rw_attribute(readahead); 93 rw_attribute(io_error_limit); 94 rw_attribute(io_error_halflife); 95 rw_attribute(verify); 96 rw_attribute(key_merging_disabled); 97 rw_attribute(gc_always_rewrite); 98 rw_attribute(freelist_percent); 99 rw_attribute(cache_replacement_policy); 100 rw_attribute(btree_shrinker_disabled); 101 rw_attribute(copy_gc_enabled); 102 rw_attribute(size); 103 104 SHOW(__bch_cached_dev) 105 { 106 struct cached_dev *dc = container_of(kobj, struct cached_dev, 107 disk.kobj); 108 const char *states[] = { "no cache", "clean", "dirty", "inconsistent" }; 109 110 #define var(stat) (dc->stat) 111 112 if (attr == &sysfs_cache_mode) 113 return bch_snprint_string_list(buf, PAGE_SIZE, 114 bch_cache_modes + 1, 115 BDEV_CACHE_MODE(&dc->sb)); 116 117 sysfs_printf(data_csum, "%i", dc->disk.data_csum); 118 var_printf(verify, "%i"); 119 var_printf(writeback_metadata, "%i"); 120 var_printf(writeback_running, "%i"); 121 var_print(writeback_delay); 122 var_print(writeback_percent); 123 sysfs_print(writeback_rate, dc->writeback_rate.rate); 124 125 var_print(writeback_rate_update_seconds); 126 var_print(writeback_rate_d_term); 127 var_print(writeback_rate_p_term_inverse); 128 var_print(writeback_rate_d_smooth); 129 130 if (attr == &sysfs_writeback_rate_debug) { 131 char dirty[20]; 132 char derivative[20]; 133 char target[20]; 134 bch_hprint(dirty, 135 bcache_dev_sectors_dirty(&dc->disk) << 9); 136 bch_hprint(derivative, dc->writeback_rate_derivative << 9); 137 bch_hprint(target, dc->writeback_rate_target << 9); 138 139 return sprintf(buf, 140 "rate:\t\t%u\n" 141 "change:\t\t%i\n" 142 "dirty:\t\t%s\n" 143 "derivative:\t%s\n" 144 "target:\t\t%s\n", 145 dc->writeback_rate.rate, 146 dc->writeback_rate_change, 147 dirty, derivative, target); 148 } 149 150 sysfs_hprint(dirty_data, 151 bcache_dev_sectors_dirty(&dc->disk) << 9); 152 153 sysfs_hprint(stripe_size, (1 << dc->disk.stripe_size_bits) << 9); 154 var_printf(partial_stripes_expensive, "%u"); 155 156 var_printf(sequential_merge, "%i"); 157 var_hprint(sequential_cutoff); 158 var_hprint(readahead); 159 160 sysfs_print(running, atomic_read(&dc->running)); 161 sysfs_print(state, states[BDEV_STATE(&dc->sb)]); 162 163 if (attr == &sysfs_label) { 164 memcpy(buf, dc->sb.label, SB_LABEL_SIZE); 165 buf[SB_LABEL_SIZE + 1] = '\0'; 166 strcat(buf, "\n"); 167 return strlen(buf); 168 } 169 170 #undef var 171 return 0; 172 } 173 SHOW_LOCKED(bch_cached_dev) 174 175 STORE(__cached_dev) 176 { 177 struct cached_dev *dc = container_of(kobj, struct cached_dev, 178 disk.kobj); 179 unsigned v = size; 180 struct cache_set *c; 181 struct kobj_uevent_env *env; 182 183 #define d_strtoul(var) sysfs_strtoul(var, dc->var) 184 #define d_strtoi_h(var) sysfs_hatoi(var, dc->var) 185 186 sysfs_strtoul(data_csum, dc->disk.data_csum); 187 d_strtoul(verify); 188 d_strtoul(writeback_metadata); 189 d_strtoul(writeback_running); 190 d_strtoul(writeback_delay); 191 sysfs_strtoul_clamp(writeback_rate, 192 dc->writeback_rate.rate, 1, 1000000); 193 sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40); 194 195 d_strtoul(writeback_rate_update_seconds); 196 d_strtoul(writeback_rate_d_term); 197 d_strtoul(writeback_rate_p_term_inverse); 198 sysfs_strtoul_clamp(writeback_rate_p_term_inverse, 199 dc->writeback_rate_p_term_inverse, 1, INT_MAX); 200 d_strtoul(writeback_rate_d_smooth); 201 202 d_strtoul(sequential_merge); 203 d_strtoi_h(sequential_cutoff); 204 d_strtoi_h(readahead); 205 206 if (attr == &sysfs_clear_stats) 207 bch_cache_accounting_clear(&dc->accounting); 208 209 if (attr == &sysfs_running && 210 strtoul_or_return(buf)) 211 bch_cached_dev_run(dc); 212 213 if (attr == &sysfs_cache_mode) { 214 ssize_t v = bch_read_string_list(buf, bch_cache_modes + 1); 215 216 if (v < 0) 217 return v; 218 219 if ((unsigned) v != BDEV_CACHE_MODE(&dc->sb)) { 220 SET_BDEV_CACHE_MODE(&dc->sb, v); 221 bch_write_bdev_super(dc, NULL); 222 } 223 } 224 225 if (attr == &sysfs_label) { 226 if (size > SB_LABEL_SIZE) 227 return -EINVAL; 228 memcpy(dc->sb.label, buf, size); 229 if (size < SB_LABEL_SIZE) 230 dc->sb.label[size] = '\0'; 231 if (size && dc->sb.label[size - 1] == '\n') 232 dc->sb.label[size - 1] = '\0'; 233 bch_write_bdev_super(dc, NULL); 234 if (dc->disk.c) { 235 memcpy(dc->disk.c->uuids[dc->disk.id].label, 236 buf, SB_LABEL_SIZE); 237 bch_uuid_write(dc->disk.c); 238 } 239 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); 240 if (!env) 241 return -ENOMEM; 242 add_uevent_var(env, "DRIVER=bcache"); 243 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid), 244 add_uevent_var(env, "CACHED_LABEL=%s", buf); 245 kobject_uevent_env( 246 &disk_to_dev(dc->disk.disk)->kobj, KOBJ_CHANGE, env->envp); 247 kfree(env); 248 } 249 250 if (attr == &sysfs_attach) { 251 if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16) 252 return -EINVAL; 253 254 list_for_each_entry(c, &bch_cache_sets, list) { 255 v = bch_cached_dev_attach(dc, c); 256 if (!v) 257 return size; 258 } 259 260 pr_err("Can't attach %s: cache set not found", buf); 261 size = v; 262 } 263 264 if (attr == &sysfs_detach && dc->disk.c) 265 bch_cached_dev_detach(dc); 266 267 if (attr == &sysfs_stop) 268 bcache_device_stop(&dc->disk); 269 270 return size; 271 } 272 273 STORE(bch_cached_dev) 274 { 275 struct cached_dev *dc = container_of(kobj, struct cached_dev, 276 disk.kobj); 277 278 mutex_lock(&bch_register_lock); 279 size = __cached_dev_store(kobj, attr, buf, size); 280 281 if (attr == &sysfs_writeback_running) 282 bch_writeback_queue(dc); 283 284 if (attr == &sysfs_writeback_percent) 285 schedule_delayed_work(&dc->writeback_rate_update, 286 dc->writeback_rate_update_seconds * HZ); 287 288 mutex_unlock(&bch_register_lock); 289 return size; 290 } 291 292 static struct attribute *bch_cached_dev_files[] = { 293 &sysfs_attach, 294 &sysfs_detach, 295 &sysfs_stop, 296 #if 0 297 &sysfs_data_csum, 298 #endif 299 &sysfs_cache_mode, 300 &sysfs_writeback_metadata, 301 &sysfs_writeback_running, 302 &sysfs_writeback_delay, 303 &sysfs_writeback_percent, 304 &sysfs_writeback_rate, 305 &sysfs_writeback_rate_update_seconds, 306 &sysfs_writeback_rate_d_term, 307 &sysfs_writeback_rate_p_term_inverse, 308 &sysfs_writeback_rate_d_smooth, 309 &sysfs_writeback_rate_debug, 310 &sysfs_dirty_data, 311 &sysfs_stripe_size, 312 &sysfs_partial_stripes_expensive, 313 &sysfs_sequential_cutoff, 314 &sysfs_sequential_merge, 315 &sysfs_clear_stats, 316 &sysfs_running, 317 &sysfs_state, 318 &sysfs_label, 319 &sysfs_readahead, 320 #ifdef CONFIG_BCACHE_DEBUG 321 &sysfs_verify, 322 #endif 323 NULL 324 }; 325 KTYPE(bch_cached_dev); 326 327 SHOW(bch_flash_dev) 328 { 329 struct bcache_device *d = container_of(kobj, struct bcache_device, 330 kobj); 331 struct uuid_entry *u = &d->c->uuids[d->id]; 332 333 sysfs_printf(data_csum, "%i", d->data_csum); 334 sysfs_hprint(size, u->sectors << 9); 335 336 if (attr == &sysfs_label) { 337 memcpy(buf, u->label, SB_LABEL_SIZE); 338 buf[SB_LABEL_SIZE + 1] = '\0'; 339 strcat(buf, "\n"); 340 return strlen(buf); 341 } 342 343 return 0; 344 } 345 346 STORE(__bch_flash_dev) 347 { 348 struct bcache_device *d = container_of(kobj, struct bcache_device, 349 kobj); 350 struct uuid_entry *u = &d->c->uuids[d->id]; 351 352 sysfs_strtoul(data_csum, d->data_csum); 353 354 if (attr == &sysfs_size) { 355 uint64_t v; 356 strtoi_h_or_return(buf, v); 357 358 u->sectors = v >> 9; 359 bch_uuid_write(d->c); 360 set_capacity(d->disk, u->sectors); 361 } 362 363 if (attr == &sysfs_label) { 364 memcpy(u->label, buf, SB_LABEL_SIZE); 365 bch_uuid_write(d->c); 366 } 367 368 if (attr == &sysfs_unregister) { 369 atomic_set(&d->detaching, 1); 370 bcache_device_stop(d); 371 } 372 373 return size; 374 } 375 STORE_LOCKED(bch_flash_dev) 376 377 static struct attribute *bch_flash_dev_files[] = { 378 &sysfs_unregister, 379 #if 0 380 &sysfs_data_csum, 381 #endif 382 &sysfs_label, 383 &sysfs_size, 384 NULL 385 }; 386 KTYPE(bch_flash_dev); 387 388 SHOW(__bch_cache_set) 389 { 390 unsigned root_usage(struct cache_set *c) 391 { 392 unsigned bytes = 0; 393 struct bkey *k; 394 struct btree *b; 395 struct btree_iter iter; 396 397 goto lock_root; 398 399 do { 400 rw_unlock(false, b); 401 lock_root: 402 b = c->root; 403 rw_lock(false, b, b->level); 404 } while (b != c->root); 405 406 for_each_key_filter(b, k, &iter, bch_ptr_bad) 407 bytes += bkey_bytes(k); 408 409 rw_unlock(false, b); 410 411 return (bytes * 100) / btree_bytes(c); 412 } 413 414 size_t cache_size(struct cache_set *c) 415 { 416 size_t ret = 0; 417 struct btree *b; 418 419 mutex_lock(&c->bucket_lock); 420 list_for_each_entry(b, &c->btree_cache, list) 421 ret += 1 << (b->page_order + PAGE_SHIFT); 422 423 mutex_unlock(&c->bucket_lock); 424 return ret; 425 } 426 427 unsigned cache_max_chain(struct cache_set *c) 428 { 429 unsigned ret = 0; 430 struct hlist_head *h; 431 432 mutex_lock(&c->bucket_lock); 433 434 for (h = c->bucket_hash; 435 h < c->bucket_hash + (1 << BUCKET_HASH_BITS); 436 h++) { 437 unsigned i = 0; 438 struct hlist_node *p; 439 440 hlist_for_each(p, h) 441 i++; 442 443 ret = max(ret, i); 444 } 445 446 mutex_unlock(&c->bucket_lock); 447 return ret; 448 } 449 450 unsigned btree_used(struct cache_set *c) 451 { 452 return div64_u64(c->gc_stats.key_bytes * 100, 453 (c->gc_stats.nodes ?: 1) * btree_bytes(c)); 454 } 455 456 unsigned average_key_size(struct cache_set *c) 457 { 458 return c->gc_stats.nkeys 459 ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys) 460 : 0; 461 } 462 463 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 464 465 sysfs_print(synchronous, CACHE_SYNC(&c->sb)); 466 sysfs_print(journal_delay_ms, c->journal_delay_ms); 467 sysfs_hprint(bucket_size, bucket_bytes(c)); 468 sysfs_hprint(block_size, block_bytes(c)); 469 sysfs_print(tree_depth, c->root->level); 470 sysfs_print(root_usage_percent, root_usage(c)); 471 472 sysfs_hprint(btree_cache_size, cache_size(c)); 473 sysfs_print(btree_cache_max_chain, cache_max_chain(c)); 474 sysfs_print(cache_available_percent, 100 - c->gc_stats.in_use); 475 476 sysfs_print_time_stats(&c->btree_gc_time, btree_gc, sec, ms); 477 sysfs_print_time_stats(&c->btree_split_time, btree_split, sec, us); 478 sysfs_print_time_stats(&c->sort_time, btree_sort, ms, us); 479 sysfs_print_time_stats(&c->btree_read_time, btree_read, ms, us); 480 sysfs_print_time_stats(&c->try_harder_time, try_harder, ms, us); 481 482 sysfs_print(btree_used_percent, btree_used(c)); 483 sysfs_print(btree_nodes, c->gc_stats.nodes); 484 sysfs_hprint(dirty_data, c->gc_stats.dirty); 485 sysfs_hprint(average_key_size, average_key_size(c)); 486 487 sysfs_print(cache_read_races, 488 atomic_long_read(&c->cache_read_races)); 489 490 sysfs_print(writeback_keys_done, 491 atomic_long_read(&c->writeback_keys_done)); 492 sysfs_print(writeback_keys_failed, 493 atomic_long_read(&c->writeback_keys_failed)); 494 495 /* See count_io_errors for why 88 */ 496 sysfs_print(io_error_halflife, c->error_decay * 88); 497 sysfs_print(io_error_limit, c->error_limit >> IO_ERROR_SHIFT); 498 499 sysfs_hprint(congested, 500 ((uint64_t) bch_get_congested(c)) << 9); 501 sysfs_print(congested_read_threshold_us, 502 c->congested_read_threshold_us); 503 sysfs_print(congested_write_threshold_us, 504 c->congested_write_threshold_us); 505 506 sysfs_print(active_journal_entries, fifo_used(&c->journal.pin)); 507 sysfs_printf(verify, "%i", c->verify); 508 sysfs_printf(key_merging_disabled, "%i", c->key_merging_disabled); 509 sysfs_printf(gc_always_rewrite, "%i", c->gc_always_rewrite); 510 sysfs_printf(btree_shrinker_disabled, "%i", c->shrinker_disabled); 511 sysfs_printf(copy_gc_enabled, "%i", c->copy_gc_enabled); 512 513 if (attr == &sysfs_bset_tree_stats) 514 return bch_bset_print_stats(c, buf); 515 516 return 0; 517 } 518 SHOW_LOCKED(bch_cache_set) 519 520 STORE(__bch_cache_set) 521 { 522 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 523 524 if (attr == &sysfs_unregister) 525 bch_cache_set_unregister(c); 526 527 if (attr == &sysfs_stop) 528 bch_cache_set_stop(c); 529 530 if (attr == &sysfs_synchronous) { 531 bool sync = strtoul_or_return(buf); 532 533 if (sync != CACHE_SYNC(&c->sb)) { 534 SET_CACHE_SYNC(&c->sb, sync); 535 bcache_write_super(c); 536 } 537 } 538 539 if (attr == &sysfs_flash_vol_create) { 540 int r; 541 uint64_t v; 542 strtoi_h_or_return(buf, v); 543 544 r = bch_flash_dev_create(c, v); 545 if (r) 546 return r; 547 } 548 549 if (attr == &sysfs_clear_stats) { 550 atomic_long_set(&c->writeback_keys_done, 0); 551 atomic_long_set(&c->writeback_keys_failed, 0); 552 553 memset(&c->gc_stats, 0, sizeof(struct gc_stat)); 554 bch_cache_accounting_clear(&c->accounting); 555 } 556 557 if (attr == &sysfs_trigger_gc) 558 bch_queue_gc(c); 559 560 if (attr == &sysfs_prune_cache) { 561 struct shrink_control sc; 562 sc.gfp_mask = GFP_KERNEL; 563 sc.nr_to_scan = strtoul_or_return(buf); 564 c->shrink.scan_objects(&c->shrink, &sc); 565 } 566 567 sysfs_strtoul(congested_read_threshold_us, 568 c->congested_read_threshold_us); 569 sysfs_strtoul(congested_write_threshold_us, 570 c->congested_write_threshold_us); 571 572 if (attr == &sysfs_io_error_limit) 573 c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT; 574 575 /* See count_io_errors() for why 88 */ 576 if (attr == &sysfs_io_error_halflife) 577 c->error_decay = strtoul_or_return(buf) / 88; 578 579 sysfs_strtoul(journal_delay_ms, c->journal_delay_ms); 580 sysfs_strtoul(verify, c->verify); 581 sysfs_strtoul(key_merging_disabled, c->key_merging_disabled); 582 sysfs_strtoul(gc_always_rewrite, c->gc_always_rewrite); 583 sysfs_strtoul(btree_shrinker_disabled, c->shrinker_disabled); 584 sysfs_strtoul(copy_gc_enabled, c->copy_gc_enabled); 585 586 return size; 587 } 588 STORE_LOCKED(bch_cache_set) 589 590 SHOW(bch_cache_set_internal) 591 { 592 struct cache_set *c = container_of(kobj, struct cache_set, internal); 593 return bch_cache_set_show(&c->kobj, attr, buf); 594 } 595 596 STORE(bch_cache_set_internal) 597 { 598 struct cache_set *c = container_of(kobj, struct cache_set, internal); 599 return bch_cache_set_store(&c->kobj, attr, buf, size); 600 } 601 602 static void bch_cache_set_internal_release(struct kobject *k) 603 { 604 } 605 606 static struct attribute *bch_cache_set_files[] = { 607 &sysfs_unregister, 608 &sysfs_stop, 609 &sysfs_synchronous, 610 &sysfs_journal_delay_ms, 611 &sysfs_flash_vol_create, 612 613 &sysfs_bucket_size, 614 &sysfs_block_size, 615 &sysfs_tree_depth, 616 &sysfs_root_usage_percent, 617 &sysfs_btree_cache_size, 618 &sysfs_cache_available_percent, 619 620 &sysfs_average_key_size, 621 &sysfs_dirty_data, 622 623 &sysfs_io_error_limit, 624 &sysfs_io_error_halflife, 625 &sysfs_congested, 626 &sysfs_congested_read_threshold_us, 627 &sysfs_congested_write_threshold_us, 628 &sysfs_clear_stats, 629 NULL 630 }; 631 KTYPE(bch_cache_set); 632 633 static struct attribute *bch_cache_set_internal_files[] = { 634 &sysfs_active_journal_entries, 635 636 sysfs_time_stats_attribute_list(btree_gc, sec, ms) 637 sysfs_time_stats_attribute_list(btree_split, sec, us) 638 sysfs_time_stats_attribute_list(btree_sort, ms, us) 639 sysfs_time_stats_attribute_list(btree_read, ms, us) 640 sysfs_time_stats_attribute_list(try_harder, ms, us) 641 642 &sysfs_btree_nodes, 643 &sysfs_btree_used_percent, 644 &sysfs_btree_cache_max_chain, 645 646 &sysfs_bset_tree_stats, 647 &sysfs_cache_read_races, 648 &sysfs_writeback_keys_done, 649 &sysfs_writeback_keys_failed, 650 651 &sysfs_trigger_gc, 652 &sysfs_prune_cache, 653 #ifdef CONFIG_BCACHE_DEBUG 654 &sysfs_verify, 655 &sysfs_key_merging_disabled, 656 #endif 657 &sysfs_gc_always_rewrite, 658 &sysfs_btree_shrinker_disabled, 659 &sysfs_copy_gc_enabled, 660 NULL 661 }; 662 KTYPE(bch_cache_set_internal); 663 664 SHOW(__bch_cache) 665 { 666 struct cache *ca = container_of(kobj, struct cache, kobj); 667 668 sysfs_hprint(bucket_size, bucket_bytes(ca)); 669 sysfs_hprint(block_size, block_bytes(ca)); 670 sysfs_print(nbuckets, ca->sb.nbuckets); 671 sysfs_print(discard, ca->discard); 672 sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9); 673 sysfs_hprint(btree_written, 674 atomic_long_read(&ca->btree_sectors_written) << 9); 675 sysfs_hprint(metadata_written, 676 (atomic_long_read(&ca->meta_sectors_written) + 677 atomic_long_read(&ca->btree_sectors_written)) << 9); 678 679 sysfs_print(io_errors, 680 atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT); 681 682 sysfs_print(freelist_percent, ca->free.size * 100 / 683 ((size_t) ca->sb.nbuckets)); 684 685 if (attr == &sysfs_cache_replacement_policy) 686 return bch_snprint_string_list(buf, PAGE_SIZE, 687 cache_replacement_policies, 688 CACHE_REPLACEMENT(&ca->sb)); 689 690 if (attr == &sysfs_priority_stats) { 691 int cmp(const void *l, const void *r) 692 { return *((uint16_t *) r) - *((uint16_t *) l); } 693 694 size_t n = ca->sb.nbuckets, i, unused, btree; 695 uint64_t sum = 0; 696 /* Compute 31 quantiles */ 697 uint16_t q[31], *p, *cached; 698 ssize_t ret; 699 700 cached = p = vmalloc(ca->sb.nbuckets * sizeof(uint16_t)); 701 if (!p) 702 return -ENOMEM; 703 704 mutex_lock(&ca->set->bucket_lock); 705 for (i = ca->sb.first_bucket; i < n; i++) 706 p[i] = ca->buckets[i].prio; 707 mutex_unlock(&ca->set->bucket_lock); 708 709 sort(p, n, sizeof(uint16_t), cmp, NULL); 710 711 while (n && 712 !cached[n - 1]) 713 --n; 714 715 unused = ca->sb.nbuckets - n; 716 717 while (cached < p + n && 718 *cached == BTREE_PRIO) 719 cached++; 720 721 btree = cached - p; 722 n -= btree; 723 724 for (i = 0; i < n; i++) 725 sum += INITIAL_PRIO - cached[i]; 726 727 if (n) 728 do_div(sum, n); 729 730 for (i = 0; i < ARRAY_SIZE(q); i++) 731 q[i] = INITIAL_PRIO - cached[n * (i + 1) / 732 (ARRAY_SIZE(q) + 1)]; 733 734 vfree(p); 735 736 ret = scnprintf(buf, PAGE_SIZE, 737 "Unused: %zu%%\n" 738 "Metadata: %zu%%\n" 739 "Average: %llu\n" 740 "Sectors per Q: %zu\n" 741 "Quantiles: [", 742 unused * 100 / (size_t) ca->sb.nbuckets, 743 btree * 100 / (size_t) ca->sb.nbuckets, sum, 744 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1)); 745 746 for (i = 0; i < ARRAY_SIZE(q); i++) 747 ret += scnprintf(buf + ret, PAGE_SIZE - ret, 748 "%u ", q[i]); 749 ret--; 750 751 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n"); 752 753 return ret; 754 } 755 756 return 0; 757 } 758 SHOW_LOCKED(bch_cache) 759 760 STORE(__bch_cache) 761 { 762 struct cache *ca = container_of(kobj, struct cache, kobj); 763 764 if (attr == &sysfs_discard) { 765 bool v = strtoul_or_return(buf); 766 767 if (blk_queue_discard(bdev_get_queue(ca->bdev))) 768 ca->discard = v; 769 770 if (v != CACHE_DISCARD(&ca->sb)) { 771 SET_CACHE_DISCARD(&ca->sb, v); 772 bcache_write_super(ca->set); 773 } 774 } 775 776 if (attr == &sysfs_cache_replacement_policy) { 777 ssize_t v = bch_read_string_list(buf, cache_replacement_policies); 778 779 if (v < 0) 780 return v; 781 782 if ((unsigned) v != CACHE_REPLACEMENT(&ca->sb)) { 783 mutex_lock(&ca->set->bucket_lock); 784 SET_CACHE_REPLACEMENT(&ca->sb, v); 785 mutex_unlock(&ca->set->bucket_lock); 786 787 bcache_write_super(ca->set); 788 } 789 } 790 791 if (attr == &sysfs_freelist_percent) { 792 DECLARE_FIFO(long, free); 793 long i; 794 size_t p = strtoul_or_return(buf); 795 796 p = clamp_t(size_t, 797 ((size_t) ca->sb.nbuckets * p) / 100, 798 roundup_pow_of_two(ca->sb.nbuckets) >> 9, 799 ca->sb.nbuckets / 2); 800 801 if (!init_fifo_exact(&free, p, GFP_KERNEL)) 802 return -ENOMEM; 803 804 mutex_lock(&ca->set->bucket_lock); 805 806 fifo_move(&free, &ca->free); 807 fifo_swap(&free, &ca->free); 808 809 mutex_unlock(&ca->set->bucket_lock); 810 811 while (fifo_pop(&free, i)) 812 atomic_dec(&ca->buckets[i].pin); 813 814 free_fifo(&free); 815 } 816 817 if (attr == &sysfs_clear_stats) { 818 atomic_long_set(&ca->sectors_written, 0); 819 atomic_long_set(&ca->btree_sectors_written, 0); 820 atomic_long_set(&ca->meta_sectors_written, 0); 821 atomic_set(&ca->io_count, 0); 822 atomic_set(&ca->io_errors, 0); 823 } 824 825 return size; 826 } 827 STORE_LOCKED(bch_cache) 828 829 static struct attribute *bch_cache_files[] = { 830 &sysfs_bucket_size, 831 &sysfs_block_size, 832 &sysfs_nbuckets, 833 &sysfs_priority_stats, 834 &sysfs_discard, 835 &sysfs_written, 836 &sysfs_btree_written, 837 &sysfs_metadata_written, 838 &sysfs_io_errors, 839 &sysfs_clear_stats, 840 &sysfs_freelist_percent, 841 &sysfs_cache_replacement_policy, 842 NULL 843 }; 844 KTYPE(bch_cache); 845