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 /* note: endlines are preserved */ 227 memcpy(dc->sb.label, buf, SB_LABEL_SIZE); 228 bch_write_bdev_super(dc, NULL); 229 if (dc->disk.c) { 230 memcpy(dc->disk.c->uuids[dc->disk.id].label, 231 buf, SB_LABEL_SIZE); 232 bch_uuid_write(dc->disk.c); 233 } 234 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); 235 if (!env) 236 return -ENOMEM; 237 add_uevent_var(env, "DRIVER=bcache"); 238 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid), 239 add_uevent_var(env, "CACHED_LABEL=%s", buf); 240 kobject_uevent_env( 241 &disk_to_dev(dc->disk.disk)->kobj, KOBJ_CHANGE, env->envp); 242 kfree(env); 243 } 244 245 if (attr == &sysfs_attach) { 246 if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16) 247 return -EINVAL; 248 249 list_for_each_entry(c, &bch_cache_sets, list) { 250 v = bch_cached_dev_attach(dc, c); 251 if (!v) 252 return size; 253 } 254 255 pr_err("Can't attach %s: cache set not found", buf); 256 size = v; 257 } 258 259 if (attr == &sysfs_detach && dc->disk.c) 260 bch_cached_dev_detach(dc); 261 262 if (attr == &sysfs_stop) 263 bcache_device_stop(&dc->disk); 264 265 return size; 266 } 267 268 STORE(bch_cached_dev) 269 { 270 struct cached_dev *dc = container_of(kobj, struct cached_dev, 271 disk.kobj); 272 273 mutex_lock(&bch_register_lock); 274 size = __cached_dev_store(kobj, attr, buf, size); 275 276 if (attr == &sysfs_writeback_running) 277 bch_writeback_queue(dc); 278 279 if (attr == &sysfs_writeback_percent) 280 schedule_delayed_work(&dc->writeback_rate_update, 281 dc->writeback_rate_update_seconds * HZ); 282 283 mutex_unlock(&bch_register_lock); 284 return size; 285 } 286 287 static struct attribute *bch_cached_dev_files[] = { 288 &sysfs_attach, 289 &sysfs_detach, 290 &sysfs_stop, 291 #if 0 292 &sysfs_data_csum, 293 #endif 294 &sysfs_cache_mode, 295 &sysfs_writeback_metadata, 296 &sysfs_writeback_running, 297 &sysfs_writeback_delay, 298 &sysfs_writeback_percent, 299 &sysfs_writeback_rate, 300 &sysfs_writeback_rate_update_seconds, 301 &sysfs_writeback_rate_d_term, 302 &sysfs_writeback_rate_p_term_inverse, 303 &sysfs_writeback_rate_d_smooth, 304 &sysfs_writeback_rate_debug, 305 &sysfs_dirty_data, 306 &sysfs_stripe_size, 307 &sysfs_partial_stripes_expensive, 308 &sysfs_sequential_cutoff, 309 &sysfs_sequential_merge, 310 &sysfs_clear_stats, 311 &sysfs_running, 312 &sysfs_state, 313 &sysfs_label, 314 &sysfs_readahead, 315 #ifdef CONFIG_BCACHE_DEBUG 316 &sysfs_verify, 317 #endif 318 NULL 319 }; 320 KTYPE(bch_cached_dev); 321 322 SHOW(bch_flash_dev) 323 { 324 struct bcache_device *d = container_of(kobj, struct bcache_device, 325 kobj); 326 struct uuid_entry *u = &d->c->uuids[d->id]; 327 328 sysfs_printf(data_csum, "%i", d->data_csum); 329 sysfs_hprint(size, u->sectors << 9); 330 331 if (attr == &sysfs_label) { 332 memcpy(buf, u->label, SB_LABEL_SIZE); 333 buf[SB_LABEL_SIZE + 1] = '\0'; 334 strcat(buf, "\n"); 335 return strlen(buf); 336 } 337 338 return 0; 339 } 340 341 STORE(__bch_flash_dev) 342 { 343 struct bcache_device *d = container_of(kobj, struct bcache_device, 344 kobj); 345 struct uuid_entry *u = &d->c->uuids[d->id]; 346 347 sysfs_strtoul(data_csum, d->data_csum); 348 349 if (attr == &sysfs_size) { 350 uint64_t v; 351 strtoi_h_or_return(buf, v); 352 353 u->sectors = v >> 9; 354 bch_uuid_write(d->c); 355 set_capacity(d->disk, u->sectors); 356 } 357 358 if (attr == &sysfs_label) { 359 memcpy(u->label, buf, SB_LABEL_SIZE); 360 bch_uuid_write(d->c); 361 } 362 363 if (attr == &sysfs_unregister) { 364 atomic_set(&d->detaching, 1); 365 bcache_device_stop(d); 366 } 367 368 return size; 369 } 370 STORE_LOCKED(bch_flash_dev) 371 372 static struct attribute *bch_flash_dev_files[] = { 373 &sysfs_unregister, 374 #if 0 375 &sysfs_data_csum, 376 #endif 377 &sysfs_label, 378 &sysfs_size, 379 NULL 380 }; 381 KTYPE(bch_flash_dev); 382 383 SHOW(__bch_cache_set) 384 { 385 unsigned root_usage(struct cache_set *c) 386 { 387 unsigned bytes = 0; 388 struct bkey *k; 389 struct btree *b; 390 struct btree_iter iter; 391 392 goto lock_root; 393 394 do { 395 rw_unlock(false, b); 396 lock_root: 397 b = c->root; 398 rw_lock(false, b, b->level); 399 } while (b != c->root); 400 401 for_each_key_filter(b, k, &iter, bch_ptr_bad) 402 bytes += bkey_bytes(k); 403 404 rw_unlock(false, b); 405 406 return (bytes * 100) / btree_bytes(c); 407 } 408 409 size_t cache_size(struct cache_set *c) 410 { 411 size_t ret = 0; 412 struct btree *b; 413 414 mutex_lock(&c->bucket_lock); 415 list_for_each_entry(b, &c->btree_cache, list) 416 ret += 1 << (b->page_order + PAGE_SHIFT); 417 418 mutex_unlock(&c->bucket_lock); 419 return ret; 420 } 421 422 unsigned cache_max_chain(struct cache_set *c) 423 { 424 unsigned ret = 0; 425 struct hlist_head *h; 426 427 mutex_lock(&c->bucket_lock); 428 429 for (h = c->bucket_hash; 430 h < c->bucket_hash + (1 << BUCKET_HASH_BITS); 431 h++) { 432 unsigned i = 0; 433 struct hlist_node *p; 434 435 hlist_for_each(p, h) 436 i++; 437 438 ret = max(ret, i); 439 } 440 441 mutex_unlock(&c->bucket_lock); 442 return ret; 443 } 444 445 unsigned btree_used(struct cache_set *c) 446 { 447 return div64_u64(c->gc_stats.key_bytes * 100, 448 (c->gc_stats.nodes ?: 1) * btree_bytes(c)); 449 } 450 451 unsigned average_key_size(struct cache_set *c) 452 { 453 return c->gc_stats.nkeys 454 ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys) 455 : 0; 456 } 457 458 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 459 460 sysfs_print(synchronous, CACHE_SYNC(&c->sb)); 461 sysfs_print(journal_delay_ms, c->journal_delay_ms); 462 sysfs_hprint(bucket_size, bucket_bytes(c)); 463 sysfs_hprint(block_size, block_bytes(c)); 464 sysfs_print(tree_depth, c->root->level); 465 sysfs_print(root_usage_percent, root_usage(c)); 466 467 sysfs_hprint(btree_cache_size, cache_size(c)); 468 sysfs_print(btree_cache_max_chain, cache_max_chain(c)); 469 sysfs_print(cache_available_percent, 100 - c->gc_stats.in_use); 470 471 sysfs_print_time_stats(&c->btree_gc_time, btree_gc, sec, ms); 472 sysfs_print_time_stats(&c->btree_split_time, btree_split, sec, us); 473 sysfs_print_time_stats(&c->sort_time, btree_sort, ms, us); 474 sysfs_print_time_stats(&c->btree_read_time, btree_read, ms, us); 475 sysfs_print_time_stats(&c->try_harder_time, try_harder, ms, us); 476 477 sysfs_print(btree_used_percent, btree_used(c)); 478 sysfs_print(btree_nodes, c->gc_stats.nodes); 479 sysfs_hprint(dirty_data, c->gc_stats.dirty); 480 sysfs_hprint(average_key_size, average_key_size(c)); 481 482 sysfs_print(cache_read_races, 483 atomic_long_read(&c->cache_read_races)); 484 485 sysfs_print(writeback_keys_done, 486 atomic_long_read(&c->writeback_keys_done)); 487 sysfs_print(writeback_keys_failed, 488 atomic_long_read(&c->writeback_keys_failed)); 489 490 /* See count_io_errors for why 88 */ 491 sysfs_print(io_error_halflife, c->error_decay * 88); 492 sysfs_print(io_error_limit, c->error_limit >> IO_ERROR_SHIFT); 493 494 sysfs_hprint(congested, 495 ((uint64_t) bch_get_congested(c)) << 9); 496 sysfs_print(congested_read_threshold_us, 497 c->congested_read_threshold_us); 498 sysfs_print(congested_write_threshold_us, 499 c->congested_write_threshold_us); 500 501 sysfs_print(active_journal_entries, fifo_used(&c->journal.pin)); 502 sysfs_printf(verify, "%i", c->verify); 503 sysfs_printf(key_merging_disabled, "%i", c->key_merging_disabled); 504 sysfs_printf(gc_always_rewrite, "%i", c->gc_always_rewrite); 505 sysfs_printf(btree_shrinker_disabled, "%i", c->shrinker_disabled); 506 sysfs_printf(copy_gc_enabled, "%i", c->copy_gc_enabled); 507 508 if (attr == &sysfs_bset_tree_stats) 509 return bch_bset_print_stats(c, buf); 510 511 return 0; 512 } 513 SHOW_LOCKED(bch_cache_set) 514 515 STORE(__bch_cache_set) 516 { 517 struct cache_set *c = container_of(kobj, struct cache_set, kobj); 518 519 if (attr == &sysfs_unregister) 520 bch_cache_set_unregister(c); 521 522 if (attr == &sysfs_stop) 523 bch_cache_set_stop(c); 524 525 if (attr == &sysfs_synchronous) { 526 bool sync = strtoul_or_return(buf); 527 528 if (sync != CACHE_SYNC(&c->sb)) { 529 SET_CACHE_SYNC(&c->sb, sync); 530 bcache_write_super(c); 531 } 532 } 533 534 if (attr == &sysfs_flash_vol_create) { 535 int r; 536 uint64_t v; 537 strtoi_h_or_return(buf, v); 538 539 r = bch_flash_dev_create(c, v); 540 if (r) 541 return r; 542 } 543 544 if (attr == &sysfs_clear_stats) { 545 atomic_long_set(&c->writeback_keys_done, 0); 546 atomic_long_set(&c->writeback_keys_failed, 0); 547 548 memset(&c->gc_stats, 0, sizeof(struct gc_stat)); 549 bch_cache_accounting_clear(&c->accounting); 550 } 551 552 if (attr == &sysfs_trigger_gc) 553 bch_queue_gc(c); 554 555 if (attr == &sysfs_prune_cache) { 556 struct shrink_control sc; 557 sc.gfp_mask = GFP_KERNEL; 558 sc.nr_to_scan = strtoul_or_return(buf); 559 c->shrink.shrink(&c->shrink, &sc); 560 } 561 562 sysfs_strtoul(congested_read_threshold_us, 563 c->congested_read_threshold_us); 564 sysfs_strtoul(congested_write_threshold_us, 565 c->congested_write_threshold_us); 566 567 if (attr == &sysfs_io_error_limit) 568 c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT; 569 570 /* See count_io_errors() for why 88 */ 571 if (attr == &sysfs_io_error_halflife) 572 c->error_decay = strtoul_or_return(buf) / 88; 573 574 sysfs_strtoul(journal_delay_ms, c->journal_delay_ms); 575 sysfs_strtoul(verify, c->verify); 576 sysfs_strtoul(key_merging_disabled, c->key_merging_disabled); 577 sysfs_strtoul(gc_always_rewrite, c->gc_always_rewrite); 578 sysfs_strtoul(btree_shrinker_disabled, c->shrinker_disabled); 579 sysfs_strtoul(copy_gc_enabled, c->copy_gc_enabled); 580 581 return size; 582 } 583 STORE_LOCKED(bch_cache_set) 584 585 SHOW(bch_cache_set_internal) 586 { 587 struct cache_set *c = container_of(kobj, struct cache_set, internal); 588 return bch_cache_set_show(&c->kobj, attr, buf); 589 } 590 591 STORE(bch_cache_set_internal) 592 { 593 struct cache_set *c = container_of(kobj, struct cache_set, internal); 594 return bch_cache_set_store(&c->kobj, attr, buf, size); 595 } 596 597 static void bch_cache_set_internal_release(struct kobject *k) 598 { 599 } 600 601 static struct attribute *bch_cache_set_files[] = { 602 &sysfs_unregister, 603 &sysfs_stop, 604 &sysfs_synchronous, 605 &sysfs_journal_delay_ms, 606 &sysfs_flash_vol_create, 607 608 &sysfs_bucket_size, 609 &sysfs_block_size, 610 &sysfs_tree_depth, 611 &sysfs_root_usage_percent, 612 &sysfs_btree_cache_size, 613 &sysfs_cache_available_percent, 614 615 &sysfs_average_key_size, 616 &sysfs_dirty_data, 617 618 &sysfs_io_error_limit, 619 &sysfs_io_error_halflife, 620 &sysfs_congested, 621 &sysfs_congested_read_threshold_us, 622 &sysfs_congested_write_threshold_us, 623 &sysfs_clear_stats, 624 NULL 625 }; 626 KTYPE(bch_cache_set); 627 628 static struct attribute *bch_cache_set_internal_files[] = { 629 &sysfs_active_journal_entries, 630 631 sysfs_time_stats_attribute_list(btree_gc, sec, ms) 632 sysfs_time_stats_attribute_list(btree_split, sec, us) 633 sysfs_time_stats_attribute_list(btree_sort, ms, us) 634 sysfs_time_stats_attribute_list(btree_read, ms, us) 635 sysfs_time_stats_attribute_list(try_harder, ms, us) 636 637 &sysfs_btree_nodes, 638 &sysfs_btree_used_percent, 639 &sysfs_btree_cache_max_chain, 640 641 &sysfs_bset_tree_stats, 642 &sysfs_cache_read_races, 643 &sysfs_writeback_keys_done, 644 &sysfs_writeback_keys_failed, 645 646 &sysfs_trigger_gc, 647 &sysfs_prune_cache, 648 #ifdef CONFIG_BCACHE_DEBUG 649 &sysfs_verify, 650 &sysfs_key_merging_disabled, 651 #endif 652 &sysfs_gc_always_rewrite, 653 &sysfs_btree_shrinker_disabled, 654 &sysfs_copy_gc_enabled, 655 NULL 656 }; 657 KTYPE(bch_cache_set_internal); 658 659 SHOW(__bch_cache) 660 { 661 struct cache *ca = container_of(kobj, struct cache, kobj); 662 663 sysfs_hprint(bucket_size, bucket_bytes(ca)); 664 sysfs_hprint(block_size, block_bytes(ca)); 665 sysfs_print(nbuckets, ca->sb.nbuckets); 666 sysfs_print(discard, ca->discard); 667 sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9); 668 sysfs_hprint(btree_written, 669 atomic_long_read(&ca->btree_sectors_written) << 9); 670 sysfs_hprint(metadata_written, 671 (atomic_long_read(&ca->meta_sectors_written) + 672 atomic_long_read(&ca->btree_sectors_written)) << 9); 673 674 sysfs_print(io_errors, 675 atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT); 676 677 sysfs_print(freelist_percent, ca->free.size * 100 / 678 ((size_t) ca->sb.nbuckets)); 679 680 if (attr == &sysfs_cache_replacement_policy) 681 return bch_snprint_string_list(buf, PAGE_SIZE, 682 cache_replacement_policies, 683 CACHE_REPLACEMENT(&ca->sb)); 684 685 if (attr == &sysfs_priority_stats) { 686 int cmp(const void *l, const void *r) 687 { return *((uint16_t *) r) - *((uint16_t *) l); } 688 689 size_t n = ca->sb.nbuckets, i, unused, btree; 690 uint64_t sum = 0; 691 /* Compute 31 quantiles */ 692 uint16_t q[31], *p, *cached; 693 ssize_t ret; 694 695 cached = p = vmalloc(ca->sb.nbuckets * sizeof(uint16_t)); 696 if (!p) 697 return -ENOMEM; 698 699 mutex_lock(&ca->set->bucket_lock); 700 for (i = ca->sb.first_bucket; i < n; i++) 701 p[i] = ca->buckets[i].prio; 702 mutex_unlock(&ca->set->bucket_lock); 703 704 sort(p, n, sizeof(uint16_t), cmp, NULL); 705 706 while (n && 707 !cached[n - 1]) 708 --n; 709 710 unused = ca->sb.nbuckets - n; 711 712 while (cached < p + n && 713 *cached == BTREE_PRIO) 714 cached++; 715 716 btree = cached - p; 717 n -= btree; 718 719 for (i = 0; i < n; i++) 720 sum += INITIAL_PRIO - cached[i]; 721 722 if (n) 723 do_div(sum, n); 724 725 for (i = 0; i < ARRAY_SIZE(q); i++) 726 q[i] = INITIAL_PRIO - cached[n * (i + 1) / 727 (ARRAY_SIZE(q) + 1)]; 728 729 vfree(p); 730 731 ret = scnprintf(buf, PAGE_SIZE, 732 "Unused: %zu%%\n" 733 "Metadata: %zu%%\n" 734 "Average: %llu\n" 735 "Sectors per Q: %zu\n" 736 "Quantiles: [", 737 unused * 100 / (size_t) ca->sb.nbuckets, 738 btree * 100 / (size_t) ca->sb.nbuckets, sum, 739 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1)); 740 741 for (i = 0; i < ARRAY_SIZE(q); i++) 742 ret += scnprintf(buf + ret, PAGE_SIZE - ret, 743 "%u ", q[i]); 744 ret--; 745 746 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n"); 747 748 return ret; 749 } 750 751 return 0; 752 } 753 SHOW_LOCKED(bch_cache) 754 755 STORE(__bch_cache) 756 { 757 struct cache *ca = container_of(kobj, struct cache, kobj); 758 759 if (attr == &sysfs_discard) { 760 bool v = strtoul_or_return(buf); 761 762 if (blk_queue_discard(bdev_get_queue(ca->bdev))) 763 ca->discard = v; 764 765 if (v != CACHE_DISCARD(&ca->sb)) { 766 SET_CACHE_DISCARD(&ca->sb, v); 767 bcache_write_super(ca->set); 768 } 769 } 770 771 if (attr == &sysfs_cache_replacement_policy) { 772 ssize_t v = bch_read_string_list(buf, cache_replacement_policies); 773 774 if (v < 0) 775 return v; 776 777 if ((unsigned) v != CACHE_REPLACEMENT(&ca->sb)) { 778 mutex_lock(&ca->set->bucket_lock); 779 SET_CACHE_REPLACEMENT(&ca->sb, v); 780 mutex_unlock(&ca->set->bucket_lock); 781 782 bcache_write_super(ca->set); 783 } 784 } 785 786 if (attr == &sysfs_freelist_percent) { 787 DECLARE_FIFO(long, free); 788 long i; 789 size_t p = strtoul_or_return(buf); 790 791 p = clamp_t(size_t, 792 ((size_t) ca->sb.nbuckets * p) / 100, 793 roundup_pow_of_two(ca->sb.nbuckets) >> 9, 794 ca->sb.nbuckets / 2); 795 796 if (!init_fifo_exact(&free, p, GFP_KERNEL)) 797 return -ENOMEM; 798 799 mutex_lock(&ca->set->bucket_lock); 800 801 fifo_move(&free, &ca->free); 802 fifo_swap(&free, &ca->free); 803 804 mutex_unlock(&ca->set->bucket_lock); 805 806 while (fifo_pop(&free, i)) 807 atomic_dec(&ca->buckets[i].pin); 808 809 free_fifo(&free); 810 } 811 812 if (attr == &sysfs_clear_stats) { 813 atomic_long_set(&ca->sectors_written, 0); 814 atomic_long_set(&ca->btree_sectors_written, 0); 815 atomic_long_set(&ca->meta_sectors_written, 0); 816 atomic_set(&ca->io_count, 0); 817 atomic_set(&ca->io_errors, 0); 818 } 819 820 return size; 821 } 822 STORE_LOCKED(bch_cache) 823 824 static struct attribute *bch_cache_files[] = { 825 &sysfs_bucket_size, 826 &sysfs_block_size, 827 &sysfs_nbuckets, 828 &sysfs_priority_stats, 829 &sysfs_discard, 830 &sysfs_written, 831 &sysfs_btree_written, 832 &sysfs_metadata_written, 833 &sysfs_io_errors, 834 &sysfs_clear_stats, 835 &sysfs_freelist_percent, 836 &sysfs_cache_replacement_policy, 837 NULL 838 }; 839 KTYPE(bch_cache); 840