1 // SPDX-License-Identifier: GPL-2.0 2 3 #include "bcachefs.h" 4 #include "btree_key_cache.h" 5 #include "btree_update.h" 6 #include "btree_write_buffer.h" 7 #include "buckets.h" 8 #include "errcode.h" 9 #include "error.h" 10 #include "journal.h" 11 #include "journal_io.h" 12 #include "journal_reclaim.h" 13 #include "replicas.h" 14 #include "sb-members.h" 15 #include "trace.h" 16 17 #include <linux/kthread.h> 18 #include <linux/sched/mm.h> 19 20 /* Free space calculations: */ 21 22 static unsigned journal_space_from(struct journal_device *ja, 23 enum journal_space_from from) 24 { 25 switch (from) { 26 case journal_space_discarded: 27 return ja->discard_idx; 28 case journal_space_clean_ondisk: 29 return ja->dirty_idx_ondisk; 30 case journal_space_clean: 31 return ja->dirty_idx; 32 default: 33 BUG(); 34 } 35 } 36 37 unsigned bch2_journal_dev_buckets_available(struct journal *j, 38 struct journal_device *ja, 39 enum journal_space_from from) 40 { 41 unsigned available = (journal_space_from(ja, from) - 42 ja->cur_idx - 1 + ja->nr) % ja->nr; 43 44 /* 45 * Don't use the last bucket unless writing the new last_seq 46 * will make another bucket available: 47 */ 48 if (available && ja->dirty_idx_ondisk == ja->dirty_idx) 49 --available; 50 51 return available; 52 } 53 54 void bch2_journal_set_watermark(struct journal *j) 55 { 56 struct bch_fs *c = container_of(j, struct bch_fs, journal); 57 bool low_on_space = j->space[journal_space_clean].total * 4 <= 58 j->space[journal_space_total].total; 59 bool low_on_pin = fifo_free(&j->pin) < j->pin.size / 4; 60 bool low_on_wb = bch2_btree_write_buffer_must_wait(c); 61 unsigned watermark = low_on_space || low_on_pin || low_on_wb 62 ? BCH_WATERMARK_reclaim 63 : BCH_WATERMARK_stripe; 64 65 if (track_event_change(&c->times[BCH_TIME_blocked_journal_low_on_space], low_on_space) || 66 track_event_change(&c->times[BCH_TIME_blocked_journal_low_on_pin], low_on_pin) || 67 track_event_change(&c->times[BCH_TIME_blocked_write_buffer_full], low_on_wb)) 68 trace_and_count(c, journal_full, c); 69 70 mod_bit(JOURNAL_SPACE_LOW, &j->flags, low_on_space || low_on_pin); 71 72 swap(watermark, j->watermark); 73 if (watermark > j->watermark) 74 journal_wake(j); 75 } 76 77 static struct journal_space 78 journal_dev_space_available(struct journal *j, struct bch_dev *ca, 79 enum journal_space_from from) 80 { 81 struct journal_device *ja = &ca->journal; 82 unsigned sectors, buckets, unwritten; 83 u64 seq; 84 85 if (from == journal_space_total) 86 return (struct journal_space) { 87 .next_entry = ca->mi.bucket_size, 88 .total = ca->mi.bucket_size * ja->nr, 89 }; 90 91 buckets = bch2_journal_dev_buckets_available(j, ja, from); 92 sectors = ja->sectors_free; 93 94 /* 95 * We that we don't allocate the space for a journal entry 96 * until we write it out - thus, account for it here: 97 */ 98 for (seq = journal_last_unwritten_seq(j); 99 seq <= journal_cur_seq(j); 100 seq++) { 101 unwritten = j->buf[seq & JOURNAL_BUF_MASK].sectors; 102 103 if (!unwritten) 104 continue; 105 106 /* entry won't fit on this device, skip: */ 107 if (unwritten > ca->mi.bucket_size) 108 continue; 109 110 if (unwritten >= sectors) { 111 if (!buckets) { 112 sectors = 0; 113 break; 114 } 115 116 buckets--; 117 sectors = ca->mi.bucket_size; 118 } 119 120 sectors -= unwritten; 121 } 122 123 if (sectors < ca->mi.bucket_size && buckets) { 124 buckets--; 125 sectors = ca->mi.bucket_size; 126 } 127 128 return (struct journal_space) { 129 .next_entry = sectors, 130 .total = sectors + buckets * ca->mi.bucket_size, 131 }; 132 } 133 134 static struct journal_space __journal_space_available(struct journal *j, unsigned nr_devs_want, 135 enum journal_space_from from) 136 { 137 struct bch_fs *c = container_of(j, struct bch_fs, journal); 138 unsigned pos, nr_devs = 0; 139 struct journal_space space, dev_space[BCH_SB_MEMBERS_MAX]; 140 141 BUG_ON(nr_devs_want > ARRAY_SIZE(dev_space)); 142 143 rcu_read_lock(); 144 for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) { 145 if (!ca->journal.nr) 146 continue; 147 148 space = journal_dev_space_available(j, ca, from); 149 if (!space.next_entry) 150 continue; 151 152 for (pos = 0; pos < nr_devs; pos++) 153 if (space.total > dev_space[pos].total) 154 break; 155 156 array_insert_item(dev_space, nr_devs, pos, space); 157 } 158 rcu_read_unlock(); 159 160 if (nr_devs < nr_devs_want) 161 return (struct journal_space) { 0, 0 }; 162 163 /* 164 * We sorted largest to smallest, and we want the smallest out of the 165 * @nr_devs_want largest devices: 166 */ 167 return dev_space[nr_devs_want - 1]; 168 } 169 170 void bch2_journal_space_available(struct journal *j) 171 { 172 struct bch_fs *c = container_of(j, struct bch_fs, journal); 173 unsigned clean, clean_ondisk, total; 174 unsigned max_entry_size = min(j->buf[0].buf_size >> 9, 175 j->buf[1].buf_size >> 9); 176 unsigned nr_online = 0, nr_devs_want; 177 bool can_discard = false; 178 int ret = 0; 179 180 lockdep_assert_held(&j->lock); 181 182 rcu_read_lock(); 183 for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) { 184 struct journal_device *ja = &ca->journal; 185 186 if (!ja->nr) 187 continue; 188 189 while (ja->dirty_idx != ja->cur_idx && 190 ja->bucket_seq[ja->dirty_idx] < journal_last_seq(j)) 191 ja->dirty_idx = (ja->dirty_idx + 1) % ja->nr; 192 193 while (ja->dirty_idx_ondisk != ja->dirty_idx && 194 ja->bucket_seq[ja->dirty_idx_ondisk] < j->last_seq_ondisk) 195 ja->dirty_idx_ondisk = (ja->dirty_idx_ondisk + 1) % ja->nr; 196 197 if (ja->discard_idx != ja->dirty_idx_ondisk) 198 can_discard = true; 199 200 max_entry_size = min_t(unsigned, max_entry_size, ca->mi.bucket_size); 201 nr_online++; 202 } 203 rcu_read_unlock(); 204 205 j->can_discard = can_discard; 206 207 if (nr_online < metadata_replicas_required(c)) { 208 ret = JOURNAL_ERR_insufficient_devices; 209 goto out; 210 } 211 212 nr_devs_want = min_t(unsigned, nr_online, c->opts.metadata_replicas); 213 214 for (unsigned i = 0; i < journal_space_nr; i++) 215 j->space[i] = __journal_space_available(j, nr_devs_want, i); 216 217 clean_ondisk = j->space[journal_space_clean_ondisk].total; 218 clean = j->space[journal_space_clean].total; 219 total = j->space[journal_space_total].total; 220 221 if (!j->space[journal_space_discarded].next_entry) 222 ret = JOURNAL_ERR_journal_full; 223 224 if ((j->space[journal_space_clean_ondisk].next_entry < 225 j->space[journal_space_clean_ondisk].total) && 226 (clean - clean_ondisk <= total / 8) && 227 (clean_ondisk * 2 > clean)) 228 set_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags); 229 else 230 clear_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags); 231 232 bch2_journal_set_watermark(j); 233 out: 234 j->cur_entry_sectors = !ret ? j->space[journal_space_discarded].next_entry : 0; 235 j->cur_entry_error = ret; 236 237 if (!ret) 238 journal_wake(j); 239 } 240 241 /* Discards - last part of journal reclaim: */ 242 243 static bool should_discard_bucket(struct journal *j, struct journal_device *ja) 244 { 245 bool ret; 246 247 spin_lock(&j->lock); 248 ret = ja->discard_idx != ja->dirty_idx_ondisk; 249 spin_unlock(&j->lock); 250 251 return ret; 252 } 253 254 /* 255 * Advance ja->discard_idx as long as it points to buckets that are no longer 256 * dirty, issuing discards if necessary: 257 */ 258 void bch2_journal_do_discards(struct journal *j) 259 { 260 struct bch_fs *c = container_of(j, struct bch_fs, journal); 261 262 mutex_lock(&j->discard_lock); 263 264 for_each_rw_member(c, ca) { 265 struct journal_device *ja = &ca->journal; 266 267 while (should_discard_bucket(j, ja)) { 268 if (!c->opts.nochanges && 269 ca->mi.discard && 270 bdev_max_discard_sectors(ca->disk_sb.bdev)) 271 blkdev_issue_discard(ca->disk_sb.bdev, 272 bucket_to_sector(ca, 273 ja->buckets[ja->discard_idx]), 274 ca->mi.bucket_size, GFP_NOFS); 275 276 spin_lock(&j->lock); 277 ja->discard_idx = (ja->discard_idx + 1) % ja->nr; 278 279 bch2_journal_space_available(j); 280 spin_unlock(&j->lock); 281 } 282 } 283 284 mutex_unlock(&j->discard_lock); 285 } 286 287 /* 288 * Journal entry pinning - machinery for holding a reference on a given journal 289 * entry, holding it open to ensure it gets replayed during recovery: 290 */ 291 292 void bch2_journal_reclaim_fast(struct journal *j) 293 { 294 bool popped = false; 295 296 lockdep_assert_held(&j->lock); 297 298 /* 299 * Unpin journal entries whose reference counts reached zero, meaning 300 * all btree nodes got written out 301 */ 302 while (!fifo_empty(&j->pin) && 303 j->pin.front <= j->seq_ondisk && 304 !atomic_read(&fifo_peek_front(&j->pin).count)) { 305 j->pin.front++; 306 popped = true; 307 } 308 309 if (popped) 310 bch2_journal_space_available(j); 311 } 312 313 bool __bch2_journal_pin_put(struct journal *j, u64 seq) 314 { 315 struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq); 316 317 return atomic_dec_and_test(&pin_list->count); 318 } 319 320 void bch2_journal_pin_put(struct journal *j, u64 seq) 321 { 322 if (__bch2_journal_pin_put(j, seq)) { 323 spin_lock(&j->lock); 324 bch2_journal_reclaim_fast(j); 325 spin_unlock(&j->lock); 326 } 327 } 328 329 static inline bool __journal_pin_drop(struct journal *j, 330 struct journal_entry_pin *pin) 331 { 332 struct journal_entry_pin_list *pin_list; 333 334 if (!journal_pin_active(pin)) 335 return false; 336 337 if (j->flush_in_progress == pin) 338 j->flush_in_progress_dropped = true; 339 340 pin_list = journal_seq_pin(j, pin->seq); 341 pin->seq = 0; 342 list_del_init(&pin->list); 343 344 /* 345 * Unpinning a journal entry may make journal_next_bucket() succeed, if 346 * writing a new last_seq will now make another bucket available: 347 */ 348 return atomic_dec_and_test(&pin_list->count) && 349 pin_list == &fifo_peek_front(&j->pin); 350 } 351 352 void bch2_journal_pin_drop(struct journal *j, 353 struct journal_entry_pin *pin) 354 { 355 spin_lock(&j->lock); 356 if (__journal_pin_drop(j, pin)) 357 bch2_journal_reclaim_fast(j); 358 spin_unlock(&j->lock); 359 } 360 361 static enum journal_pin_type journal_pin_type(journal_pin_flush_fn fn) 362 { 363 if (fn == bch2_btree_node_flush0 || 364 fn == bch2_btree_node_flush1) 365 return JOURNAL_PIN_btree; 366 else if (fn == bch2_btree_key_cache_journal_flush) 367 return JOURNAL_PIN_key_cache; 368 else 369 return JOURNAL_PIN_other; 370 } 371 372 static inline void bch2_journal_pin_set_locked(struct journal *j, u64 seq, 373 struct journal_entry_pin *pin, 374 journal_pin_flush_fn flush_fn, 375 enum journal_pin_type type) 376 { 377 struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq); 378 379 /* 380 * flush_fn is how we identify journal pins in debugfs, so must always 381 * exist, even if it doesn't do anything: 382 */ 383 BUG_ON(!flush_fn); 384 385 atomic_inc(&pin_list->count); 386 pin->seq = seq; 387 pin->flush = flush_fn; 388 list_add(&pin->list, &pin_list->list[type]); 389 } 390 391 void bch2_journal_pin_copy(struct journal *j, 392 struct journal_entry_pin *dst, 393 struct journal_entry_pin *src, 394 journal_pin_flush_fn flush_fn) 395 { 396 spin_lock(&j->lock); 397 398 u64 seq = READ_ONCE(src->seq); 399 400 if (seq < journal_last_seq(j)) { 401 /* 402 * bch2_journal_pin_copy() raced with bch2_journal_pin_drop() on 403 * the src pin - with the pin dropped, the entry to pin might no 404 * longer to exist, but that means there's no longer anything to 405 * copy and we can bail out here: 406 */ 407 spin_unlock(&j->lock); 408 return; 409 } 410 411 bool reclaim = __journal_pin_drop(j, dst); 412 413 bch2_journal_pin_set_locked(j, seq, dst, flush_fn, journal_pin_type(flush_fn)); 414 415 if (reclaim) 416 bch2_journal_reclaim_fast(j); 417 418 /* 419 * If the journal is currently full, we might want to call flush_fn 420 * immediately: 421 */ 422 if (seq == journal_last_seq(j)) 423 journal_wake(j); 424 spin_unlock(&j->lock); 425 } 426 427 void bch2_journal_pin_set(struct journal *j, u64 seq, 428 struct journal_entry_pin *pin, 429 journal_pin_flush_fn flush_fn) 430 { 431 spin_lock(&j->lock); 432 433 BUG_ON(seq < journal_last_seq(j)); 434 435 bool reclaim = __journal_pin_drop(j, pin); 436 437 bch2_journal_pin_set_locked(j, seq, pin, flush_fn, journal_pin_type(flush_fn)); 438 439 if (reclaim) 440 bch2_journal_reclaim_fast(j); 441 /* 442 * If the journal is currently full, we might want to call flush_fn 443 * immediately: 444 */ 445 if (seq == journal_last_seq(j)) 446 journal_wake(j); 447 448 spin_unlock(&j->lock); 449 } 450 451 /** 452 * bch2_journal_pin_flush: ensure journal pin callback is no longer running 453 * @j: journal object 454 * @pin: pin to flush 455 */ 456 void bch2_journal_pin_flush(struct journal *j, struct journal_entry_pin *pin) 457 { 458 BUG_ON(journal_pin_active(pin)); 459 460 wait_event(j->pin_flush_wait, j->flush_in_progress != pin); 461 } 462 463 /* 464 * Journal reclaim: flush references to open journal entries to reclaim space in 465 * the journal 466 * 467 * May be done by the journal code in the background as needed to free up space 468 * for more journal entries, or as part of doing a clean shutdown, or to migrate 469 * data off of a specific device: 470 */ 471 472 static struct journal_entry_pin * 473 journal_get_next_pin(struct journal *j, 474 u64 seq_to_flush, 475 unsigned allowed_below_seq, 476 unsigned allowed_above_seq, 477 u64 *seq) 478 { 479 struct journal_entry_pin_list *pin_list; 480 struct journal_entry_pin *ret = NULL; 481 unsigned i; 482 483 fifo_for_each_entry_ptr(pin_list, &j->pin, *seq) { 484 if (*seq > seq_to_flush && !allowed_above_seq) 485 break; 486 487 for (i = 0; i < JOURNAL_PIN_NR; i++) 488 if ((((1U << i) & allowed_below_seq) && *seq <= seq_to_flush) || 489 ((1U << i) & allowed_above_seq)) { 490 ret = list_first_entry_or_null(&pin_list->list[i], 491 struct journal_entry_pin, list); 492 if (ret) 493 return ret; 494 } 495 } 496 497 return NULL; 498 } 499 500 /* returns true if we did work */ 501 static size_t journal_flush_pins(struct journal *j, 502 u64 seq_to_flush, 503 unsigned allowed_below_seq, 504 unsigned allowed_above_seq, 505 unsigned min_any, 506 unsigned min_key_cache) 507 { 508 struct journal_entry_pin *pin; 509 size_t nr_flushed = 0; 510 journal_pin_flush_fn flush_fn; 511 u64 seq; 512 int err; 513 514 lockdep_assert_held(&j->reclaim_lock); 515 516 while (1) { 517 unsigned allowed_above = allowed_above_seq; 518 unsigned allowed_below = allowed_below_seq; 519 520 if (min_any) { 521 allowed_above |= ~0; 522 allowed_below |= ~0; 523 } 524 525 if (min_key_cache) { 526 allowed_above |= 1U << JOURNAL_PIN_key_cache; 527 allowed_below |= 1U << JOURNAL_PIN_key_cache; 528 } 529 530 cond_resched(); 531 532 j->last_flushed = jiffies; 533 534 spin_lock(&j->lock); 535 pin = journal_get_next_pin(j, seq_to_flush, allowed_below, allowed_above, &seq); 536 if (pin) { 537 BUG_ON(j->flush_in_progress); 538 j->flush_in_progress = pin; 539 j->flush_in_progress_dropped = false; 540 flush_fn = pin->flush; 541 } 542 spin_unlock(&j->lock); 543 544 if (!pin) 545 break; 546 547 if (min_key_cache && pin->flush == bch2_btree_key_cache_journal_flush) 548 min_key_cache--; 549 550 if (min_any) 551 min_any--; 552 553 err = flush_fn(j, pin, seq); 554 555 spin_lock(&j->lock); 556 /* Pin might have been dropped or rearmed: */ 557 if (likely(!err && !j->flush_in_progress_dropped)) 558 list_move(&pin->list, &journal_seq_pin(j, seq)->flushed); 559 j->flush_in_progress = NULL; 560 j->flush_in_progress_dropped = false; 561 spin_unlock(&j->lock); 562 563 wake_up(&j->pin_flush_wait); 564 565 if (err) 566 break; 567 568 nr_flushed++; 569 } 570 571 return nr_flushed; 572 } 573 574 static u64 journal_seq_to_flush(struct journal *j) 575 { 576 struct bch_fs *c = container_of(j, struct bch_fs, journal); 577 u64 seq_to_flush = 0; 578 579 spin_lock(&j->lock); 580 581 for_each_rw_member(c, ca) { 582 struct journal_device *ja = &ca->journal; 583 unsigned nr_buckets, bucket_to_flush; 584 585 if (!ja->nr) 586 continue; 587 588 /* Try to keep the journal at most half full: */ 589 nr_buckets = ja->nr / 2; 590 591 nr_buckets = min(nr_buckets, ja->nr); 592 593 bucket_to_flush = (ja->cur_idx + nr_buckets) % ja->nr; 594 seq_to_flush = max(seq_to_flush, 595 ja->bucket_seq[bucket_to_flush]); 596 } 597 598 /* Also flush if the pin fifo is more than half full */ 599 seq_to_flush = max_t(s64, seq_to_flush, 600 (s64) journal_cur_seq(j) - 601 (j->pin.size >> 1)); 602 spin_unlock(&j->lock); 603 604 return seq_to_flush; 605 } 606 607 /** 608 * __bch2_journal_reclaim - free up journal buckets 609 * @j: journal object 610 * @direct: direct or background reclaim? 611 * @kicked: requested to run since we last ran? 612 * Returns: 0 on success, or -EIO if the journal has been shutdown 613 * 614 * Background journal reclaim writes out btree nodes. It should be run 615 * early enough so that we never completely run out of journal buckets. 616 * 617 * High watermarks for triggering background reclaim: 618 * - FIFO has fewer than 512 entries left 619 * - fewer than 25% journal buckets free 620 * 621 * Background reclaim runs until low watermarks are reached: 622 * - FIFO has more than 1024 entries left 623 * - more than 50% journal buckets free 624 * 625 * As long as a reclaim can complete in the time it takes to fill up 626 * 512 journal entries or 25% of all journal buckets, then 627 * journal_next_bucket() should not stall. 628 */ 629 static int __bch2_journal_reclaim(struct journal *j, bool direct, bool kicked) 630 { 631 struct bch_fs *c = container_of(j, struct bch_fs, journal); 632 bool kthread = (current->flags & PF_KTHREAD) != 0; 633 u64 seq_to_flush; 634 size_t min_nr, min_key_cache, nr_flushed; 635 unsigned flags; 636 int ret = 0; 637 638 /* 639 * We can't invoke memory reclaim while holding the reclaim_lock - 640 * journal reclaim is required to make progress for memory reclaim 641 * (cleaning the caches), so we can't get stuck in memory reclaim while 642 * we're holding the reclaim lock: 643 */ 644 lockdep_assert_held(&j->reclaim_lock); 645 flags = memalloc_noreclaim_save(); 646 647 do { 648 if (kthread && kthread_should_stop()) 649 break; 650 651 if (bch2_journal_error(j)) { 652 ret = -EIO; 653 break; 654 } 655 656 bch2_journal_do_discards(j); 657 658 seq_to_flush = journal_seq_to_flush(j); 659 min_nr = 0; 660 661 /* 662 * If it's been longer than j->reclaim_delay_ms since we last flushed, 663 * make sure to flush at least one journal pin: 664 */ 665 if (time_after(jiffies, j->last_flushed + 666 msecs_to_jiffies(c->opts.journal_reclaim_delay))) 667 min_nr = 1; 668 669 if (j->watermark != BCH_WATERMARK_stripe) 670 min_nr = 1; 671 672 if (atomic_read(&c->btree_cache.dirty) * 2 > c->btree_cache.used) 673 min_nr = 1; 674 675 min_key_cache = min(bch2_nr_btree_keys_need_flush(c), (size_t) 128); 676 677 trace_and_count(c, journal_reclaim_start, c, 678 direct, kicked, 679 min_nr, min_key_cache, 680 atomic_read(&c->btree_cache.dirty), 681 c->btree_cache.used, 682 atomic_long_read(&c->btree_key_cache.nr_dirty), 683 atomic_long_read(&c->btree_key_cache.nr_keys)); 684 685 nr_flushed = journal_flush_pins(j, seq_to_flush, 686 ~0, 0, 687 min_nr, min_key_cache); 688 689 if (direct) 690 j->nr_direct_reclaim += nr_flushed; 691 else 692 j->nr_background_reclaim += nr_flushed; 693 trace_and_count(c, journal_reclaim_finish, c, nr_flushed); 694 695 if (nr_flushed) 696 wake_up(&j->reclaim_wait); 697 } while ((min_nr || min_key_cache) && nr_flushed && !direct); 698 699 memalloc_noreclaim_restore(flags); 700 701 return ret; 702 } 703 704 int bch2_journal_reclaim(struct journal *j) 705 { 706 return __bch2_journal_reclaim(j, true, true); 707 } 708 709 static int bch2_journal_reclaim_thread(void *arg) 710 { 711 struct journal *j = arg; 712 struct bch_fs *c = container_of(j, struct bch_fs, journal); 713 unsigned long delay, now; 714 bool journal_empty; 715 int ret = 0; 716 717 set_freezable(); 718 719 j->last_flushed = jiffies; 720 721 while (!ret && !kthread_should_stop()) { 722 bool kicked = j->reclaim_kicked; 723 724 j->reclaim_kicked = false; 725 726 mutex_lock(&j->reclaim_lock); 727 ret = __bch2_journal_reclaim(j, false, kicked); 728 mutex_unlock(&j->reclaim_lock); 729 730 now = jiffies; 731 delay = msecs_to_jiffies(c->opts.journal_reclaim_delay); 732 j->next_reclaim = j->last_flushed + delay; 733 734 if (!time_in_range(j->next_reclaim, now, now + delay)) 735 j->next_reclaim = now + delay; 736 737 while (1) { 738 set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); 739 if (kthread_should_stop()) 740 break; 741 if (j->reclaim_kicked) 742 break; 743 744 spin_lock(&j->lock); 745 journal_empty = fifo_empty(&j->pin); 746 spin_unlock(&j->lock); 747 748 if (journal_empty) 749 schedule(); 750 else if (time_after(j->next_reclaim, jiffies)) 751 schedule_timeout(j->next_reclaim - jiffies); 752 else 753 break; 754 } 755 __set_current_state(TASK_RUNNING); 756 } 757 758 return 0; 759 } 760 761 void bch2_journal_reclaim_stop(struct journal *j) 762 { 763 struct task_struct *p = j->reclaim_thread; 764 765 j->reclaim_thread = NULL; 766 767 if (p) { 768 kthread_stop(p); 769 put_task_struct(p); 770 } 771 } 772 773 int bch2_journal_reclaim_start(struct journal *j) 774 { 775 struct bch_fs *c = container_of(j, struct bch_fs, journal); 776 struct task_struct *p; 777 int ret; 778 779 if (j->reclaim_thread) 780 return 0; 781 782 p = kthread_create(bch2_journal_reclaim_thread, j, 783 "bch-reclaim/%s", c->name); 784 ret = PTR_ERR_OR_ZERO(p); 785 bch_err_msg(c, ret, "creating journal reclaim thread"); 786 if (ret) 787 return ret; 788 789 get_task_struct(p); 790 j->reclaim_thread = p; 791 wake_up_process(p); 792 return 0; 793 } 794 795 static int journal_flush_done(struct journal *j, u64 seq_to_flush, 796 bool *did_work) 797 { 798 int ret; 799 800 ret = bch2_journal_error(j); 801 if (ret) 802 return ret; 803 804 mutex_lock(&j->reclaim_lock); 805 806 if (journal_flush_pins(j, seq_to_flush, 807 (1U << JOURNAL_PIN_key_cache)| 808 (1U << JOURNAL_PIN_other), 0, 0, 0) || 809 journal_flush_pins(j, seq_to_flush, 810 (1U << JOURNAL_PIN_btree), 0, 0, 0)) 811 *did_work = true; 812 813 if (seq_to_flush > journal_cur_seq(j)) 814 bch2_journal_entry_close(j); 815 816 spin_lock(&j->lock); 817 /* 818 * If journal replay hasn't completed, the unreplayed journal entries 819 * hold refs on their corresponding sequence numbers 820 */ 821 ret = !test_bit(JOURNAL_REPLAY_DONE, &j->flags) || 822 journal_last_seq(j) > seq_to_flush || 823 !fifo_used(&j->pin); 824 825 spin_unlock(&j->lock); 826 mutex_unlock(&j->reclaim_lock); 827 828 return ret; 829 } 830 831 bool bch2_journal_flush_pins(struct journal *j, u64 seq_to_flush) 832 { 833 /* time_stats this */ 834 bool did_work = false; 835 836 if (!test_bit(JOURNAL_STARTED, &j->flags)) 837 return false; 838 839 closure_wait_event(&j->async_wait, 840 journal_flush_done(j, seq_to_flush, &did_work)); 841 842 return did_work; 843 } 844 845 int bch2_journal_flush_device_pins(struct journal *j, int dev_idx) 846 { 847 struct bch_fs *c = container_of(j, struct bch_fs, journal); 848 struct journal_entry_pin_list *p; 849 u64 iter, seq = 0; 850 int ret = 0; 851 852 spin_lock(&j->lock); 853 fifo_for_each_entry_ptr(p, &j->pin, iter) 854 if (dev_idx >= 0 855 ? bch2_dev_list_has_dev(p->devs, dev_idx) 856 : p->devs.nr < c->opts.metadata_replicas) 857 seq = iter; 858 spin_unlock(&j->lock); 859 860 bch2_journal_flush_pins(j, seq); 861 862 ret = bch2_journal_error(j); 863 if (ret) 864 return ret; 865 866 mutex_lock(&c->replicas_gc_lock); 867 bch2_replicas_gc_start(c, 1 << BCH_DATA_journal); 868 869 /* 870 * Now that we've populated replicas_gc, write to the journal to mark 871 * active journal devices. This handles the case where the journal might 872 * be empty. Otherwise we could clear all journal replicas and 873 * temporarily put the fs into an unrecoverable state. Journal recovery 874 * expects to find devices marked for journal data on unclean mount. 875 */ 876 ret = bch2_journal_meta(&c->journal); 877 if (ret) 878 goto err; 879 880 seq = 0; 881 spin_lock(&j->lock); 882 while (!ret) { 883 struct bch_replicas_padded replicas; 884 885 seq = max(seq, journal_last_seq(j)); 886 if (seq >= j->pin.back) 887 break; 888 bch2_devlist_to_replicas(&replicas.e, BCH_DATA_journal, 889 journal_seq_pin(j, seq)->devs); 890 seq++; 891 892 if (replicas.e.nr_devs) { 893 spin_unlock(&j->lock); 894 ret = bch2_mark_replicas(c, &replicas.e); 895 spin_lock(&j->lock); 896 } 897 } 898 spin_unlock(&j->lock); 899 err: 900 ret = bch2_replicas_gc_end(c, ret); 901 mutex_unlock(&c->replicas_gc_lock); 902 903 return ret; 904 } 905