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], 66 &j->low_on_space_start, low_on_space) || 67 track_event_change(&c->times[BCH_TIME_blocked_journal_low_on_pin], 68 &j->low_on_pin_start, low_on_pin) || 69 track_event_change(&c->times[BCH_TIME_blocked_write_buffer_full], 70 &j->write_buffer_full_start, low_on_wb)) 71 trace_and_count(c, journal_full, c); 72 73 swap(watermark, j->watermark); 74 if (watermark > j->watermark) 75 journal_wake(j); 76 } 77 78 static struct journal_space 79 journal_dev_space_available(struct journal *j, struct bch_dev *ca, 80 enum journal_space_from from) 81 { 82 struct journal_device *ja = &ca->journal; 83 unsigned sectors, buckets, unwritten; 84 u64 seq; 85 86 if (from == journal_space_total) 87 return (struct journal_space) { 88 .next_entry = ca->mi.bucket_size, 89 .total = ca->mi.bucket_size * ja->nr, 90 }; 91 92 buckets = bch2_journal_dev_buckets_available(j, ja, from); 93 sectors = ja->sectors_free; 94 95 /* 96 * We that we don't allocate the space for a journal entry 97 * until we write it out - thus, account for it here: 98 */ 99 for (seq = journal_last_unwritten_seq(j); 100 seq <= journal_cur_seq(j); 101 seq++) { 102 unwritten = j->buf[seq & JOURNAL_BUF_MASK].sectors; 103 104 if (!unwritten) 105 continue; 106 107 /* entry won't fit on this device, skip: */ 108 if (unwritten > ca->mi.bucket_size) 109 continue; 110 111 if (unwritten >= sectors) { 112 if (!buckets) { 113 sectors = 0; 114 break; 115 } 116 117 buckets--; 118 sectors = ca->mi.bucket_size; 119 } 120 121 sectors -= unwritten; 122 } 123 124 if (sectors < ca->mi.bucket_size && buckets) { 125 buckets--; 126 sectors = ca->mi.bucket_size; 127 } 128 129 return (struct journal_space) { 130 .next_entry = sectors, 131 .total = sectors + buckets * ca->mi.bucket_size, 132 }; 133 } 134 135 static struct journal_space __journal_space_available(struct journal *j, unsigned nr_devs_want, 136 enum journal_space_from from) 137 { 138 struct bch_fs *c = container_of(j, struct bch_fs, journal); 139 unsigned pos, nr_devs = 0; 140 struct journal_space space, dev_space[BCH_SB_MEMBERS_MAX]; 141 142 BUG_ON(nr_devs_want > ARRAY_SIZE(dev_space)); 143 144 rcu_read_lock(); 145 for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) { 146 if (!ca->journal.nr) 147 continue; 148 149 space = journal_dev_space_available(j, ca, from); 150 if (!space.next_entry) 151 continue; 152 153 for (pos = 0; pos < nr_devs; pos++) 154 if (space.total > dev_space[pos].total) 155 break; 156 157 array_insert_item(dev_space, nr_devs, pos, space); 158 } 159 rcu_read_unlock(); 160 161 if (nr_devs < nr_devs_want) 162 return (struct journal_space) { 0, 0 }; 163 164 /* 165 * We sorted largest to smallest, and we want the smallest out of the 166 * @nr_devs_want largest devices: 167 */ 168 return dev_space[nr_devs_want - 1]; 169 } 170 171 void bch2_journal_space_available(struct journal *j) 172 { 173 struct bch_fs *c = container_of(j, struct bch_fs, journal); 174 unsigned clean, clean_ondisk, total; 175 unsigned max_entry_size = min(j->buf[0].buf_size >> 9, 176 j->buf[1].buf_size >> 9); 177 unsigned nr_online = 0, nr_devs_want; 178 bool can_discard = false; 179 int ret = 0; 180 181 lockdep_assert_held(&j->lock); 182 183 rcu_read_lock(); 184 for_each_member_device_rcu(c, ca, &c->rw_devs[BCH_DATA_journal]) { 185 struct journal_device *ja = &ca->journal; 186 187 if (!ja->nr) 188 continue; 189 190 while (ja->dirty_idx != ja->cur_idx && 191 ja->bucket_seq[ja->dirty_idx] < journal_last_seq(j)) 192 ja->dirty_idx = (ja->dirty_idx + 1) % ja->nr; 193 194 while (ja->dirty_idx_ondisk != ja->dirty_idx && 195 ja->bucket_seq[ja->dirty_idx_ondisk] < j->last_seq_ondisk) 196 ja->dirty_idx_ondisk = (ja->dirty_idx_ondisk + 1) % ja->nr; 197 198 if (ja->discard_idx != ja->dirty_idx_ondisk) 199 can_discard = true; 200 201 max_entry_size = min_t(unsigned, max_entry_size, ca->mi.bucket_size); 202 nr_online++; 203 } 204 rcu_read_unlock(); 205 206 j->can_discard = can_discard; 207 208 if (nr_online < metadata_replicas_required(c)) { 209 ret = JOURNAL_ERR_insufficient_devices; 210 goto out; 211 } 212 213 nr_devs_want = min_t(unsigned, nr_online, c->opts.metadata_replicas); 214 215 for (unsigned i = 0; i < journal_space_nr; i++) 216 j->space[i] = __journal_space_available(j, nr_devs_want, i); 217 218 clean_ondisk = j->space[journal_space_clean_ondisk].total; 219 clean = j->space[journal_space_clean].total; 220 total = j->space[journal_space_total].total; 221 222 if (!j->space[journal_space_discarded].next_entry) 223 ret = JOURNAL_ERR_journal_full; 224 225 if ((j->space[journal_space_clean_ondisk].next_entry < 226 j->space[journal_space_clean_ondisk].total) && 227 (clean - clean_ondisk <= total / 8) && 228 (clean_ondisk * 2 > clean)) 229 set_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags); 230 else 231 clear_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags); 232 233 bch2_journal_set_watermark(j); 234 out: 235 j->cur_entry_sectors = !ret ? j->space[journal_space_discarded].next_entry : 0; 236 j->cur_entry_error = ret; 237 238 if (!ret) 239 journal_wake(j); 240 } 241 242 /* Discards - last part of journal reclaim: */ 243 244 static bool should_discard_bucket(struct journal *j, struct journal_device *ja) 245 { 246 bool ret; 247 248 spin_lock(&j->lock); 249 ret = ja->discard_idx != ja->dirty_idx_ondisk; 250 spin_unlock(&j->lock); 251 252 return ret; 253 } 254 255 /* 256 * Advance ja->discard_idx as long as it points to buckets that are no longer 257 * dirty, issuing discards if necessary: 258 */ 259 void bch2_journal_do_discards(struct journal *j) 260 { 261 struct bch_fs *c = container_of(j, struct bch_fs, journal); 262 263 mutex_lock(&j->discard_lock); 264 265 for_each_rw_member(c, ca) { 266 struct journal_device *ja = &ca->journal; 267 268 while (should_discard_bucket(j, ja)) { 269 if (!c->opts.nochanges && 270 ca->mi.discard && 271 bdev_max_discard_sectors(ca->disk_sb.bdev)) 272 blkdev_issue_discard(ca->disk_sb.bdev, 273 bucket_to_sector(ca, 274 ja->buckets[ja->discard_idx]), 275 ca->mi.bucket_size, GFP_NOFS); 276 277 spin_lock(&j->lock); 278 ja->discard_idx = (ja->discard_idx + 1) % ja->nr; 279 280 bch2_journal_space_available(j); 281 spin_unlock(&j->lock); 282 } 283 } 284 285 mutex_unlock(&j->discard_lock); 286 } 287 288 /* 289 * Journal entry pinning - machinery for holding a reference on a given journal 290 * entry, holding it open to ensure it gets replayed during recovery: 291 */ 292 293 void bch2_journal_reclaim_fast(struct journal *j) 294 { 295 bool popped = false; 296 297 lockdep_assert_held(&j->lock); 298 299 /* 300 * Unpin journal entries whose reference counts reached zero, meaning 301 * all btree nodes got written out 302 */ 303 while (!fifo_empty(&j->pin) && 304 j->pin.front <= j->seq_ondisk && 305 !atomic_read(&fifo_peek_front(&j->pin).count)) { 306 j->pin.front++; 307 popped = true; 308 } 309 310 if (popped) 311 bch2_journal_space_available(j); 312 } 313 314 bool __bch2_journal_pin_put(struct journal *j, u64 seq) 315 { 316 struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq); 317 318 return atomic_dec_and_test(&pin_list->count); 319 } 320 321 void bch2_journal_pin_put(struct journal *j, u64 seq) 322 { 323 if (__bch2_journal_pin_put(j, seq)) { 324 spin_lock(&j->lock); 325 bch2_journal_reclaim_fast(j); 326 spin_unlock(&j->lock); 327 } 328 } 329 330 static inline bool __journal_pin_drop(struct journal *j, 331 struct journal_entry_pin *pin) 332 { 333 struct journal_entry_pin_list *pin_list; 334 335 if (!journal_pin_active(pin)) 336 return false; 337 338 if (j->flush_in_progress == pin) 339 j->flush_in_progress_dropped = true; 340 341 pin_list = journal_seq_pin(j, pin->seq); 342 pin->seq = 0; 343 list_del_init(&pin->list); 344 345 /* 346 * Unpinning a journal entry may make journal_next_bucket() succeed, if 347 * writing a new last_seq will now make another bucket available: 348 */ 349 return atomic_dec_and_test(&pin_list->count) && 350 pin_list == &fifo_peek_front(&j->pin); 351 } 352 353 void bch2_journal_pin_drop(struct journal *j, 354 struct journal_entry_pin *pin) 355 { 356 spin_lock(&j->lock); 357 if (__journal_pin_drop(j, pin)) 358 bch2_journal_reclaim_fast(j); 359 spin_unlock(&j->lock); 360 } 361 362 static enum journal_pin_type journal_pin_type(journal_pin_flush_fn fn) 363 { 364 if (fn == bch2_btree_node_flush0 || 365 fn == bch2_btree_node_flush1) 366 return JOURNAL_PIN_btree; 367 else if (fn == bch2_btree_key_cache_journal_flush) 368 return JOURNAL_PIN_key_cache; 369 else 370 return JOURNAL_PIN_other; 371 } 372 373 static inline void bch2_journal_pin_set_locked(struct journal *j, u64 seq, 374 struct journal_entry_pin *pin, 375 journal_pin_flush_fn flush_fn, 376 enum journal_pin_type type) 377 { 378 struct journal_entry_pin_list *pin_list = journal_seq_pin(j, seq); 379 380 /* 381 * flush_fn is how we identify journal pins in debugfs, so must always 382 * exist, even if it doesn't do anything: 383 */ 384 BUG_ON(!flush_fn); 385 386 atomic_inc(&pin_list->count); 387 pin->seq = seq; 388 pin->flush = flush_fn; 389 list_add(&pin->list, &pin_list->list[type]); 390 } 391 392 void bch2_journal_pin_copy(struct journal *j, 393 struct journal_entry_pin *dst, 394 struct journal_entry_pin *src, 395 journal_pin_flush_fn flush_fn) 396 { 397 bool reclaim; 398 399 spin_lock(&j->lock); 400 401 u64 seq = READ_ONCE(src->seq); 402 403 if (seq < journal_last_seq(j)) { 404 /* 405 * bch2_journal_pin_copy() raced with bch2_journal_pin_drop() on 406 * the src pin - with the pin dropped, the entry to pin might no 407 * longer to exist, but that means there's no longer anything to 408 * copy and we can bail out here: 409 */ 410 spin_unlock(&j->lock); 411 return; 412 } 413 414 reclaim = __journal_pin_drop(j, dst); 415 416 bch2_journal_pin_set_locked(j, seq, dst, flush_fn, journal_pin_type(flush_fn)); 417 418 if (reclaim) 419 bch2_journal_reclaim_fast(j); 420 spin_unlock(&j->lock); 421 422 /* 423 * If the journal is currently full, we might want to call flush_fn 424 * immediately: 425 */ 426 journal_wake(j); 427 } 428 429 void bch2_journal_pin_set(struct journal *j, u64 seq, 430 struct journal_entry_pin *pin, 431 journal_pin_flush_fn flush_fn) 432 { 433 bool reclaim; 434 435 spin_lock(&j->lock); 436 437 BUG_ON(seq < journal_last_seq(j)); 438 439 reclaim = __journal_pin_drop(j, pin); 440 441 bch2_journal_pin_set_locked(j, seq, pin, flush_fn, journal_pin_type(flush_fn)); 442 443 if (reclaim) 444 bch2_journal_reclaim_fast(j); 445 spin_unlock(&j->lock); 446 447 /* 448 * If the journal is currently full, we might want to call flush_fn 449 * immediately: 450 */ 451 journal_wake(j); 452 } 453 454 /** 455 * bch2_journal_pin_flush: ensure journal pin callback is no longer running 456 * @j: journal object 457 * @pin: pin to flush 458 */ 459 void bch2_journal_pin_flush(struct journal *j, struct journal_entry_pin *pin) 460 { 461 BUG_ON(journal_pin_active(pin)); 462 463 wait_event(j->pin_flush_wait, j->flush_in_progress != pin); 464 } 465 466 /* 467 * Journal reclaim: flush references to open journal entries to reclaim space in 468 * the journal 469 * 470 * May be done by the journal code in the background as needed to free up space 471 * for more journal entries, or as part of doing a clean shutdown, or to migrate 472 * data off of a specific device: 473 */ 474 475 static struct journal_entry_pin * 476 journal_get_next_pin(struct journal *j, 477 u64 seq_to_flush, 478 unsigned allowed_below_seq, 479 unsigned allowed_above_seq, 480 u64 *seq) 481 { 482 struct journal_entry_pin_list *pin_list; 483 struct journal_entry_pin *ret = NULL; 484 unsigned i; 485 486 fifo_for_each_entry_ptr(pin_list, &j->pin, *seq) { 487 if (*seq > seq_to_flush && !allowed_above_seq) 488 break; 489 490 for (i = 0; i < JOURNAL_PIN_NR; i++) 491 if ((((1U << i) & allowed_below_seq) && *seq <= seq_to_flush) || 492 ((1U << i) & allowed_above_seq)) { 493 ret = list_first_entry_or_null(&pin_list->list[i], 494 struct journal_entry_pin, list); 495 if (ret) 496 return ret; 497 } 498 } 499 500 return NULL; 501 } 502 503 /* returns true if we did work */ 504 static size_t journal_flush_pins(struct journal *j, 505 u64 seq_to_flush, 506 unsigned allowed_below_seq, 507 unsigned allowed_above_seq, 508 unsigned min_any, 509 unsigned min_key_cache) 510 { 511 struct journal_entry_pin *pin; 512 size_t nr_flushed = 0; 513 journal_pin_flush_fn flush_fn; 514 u64 seq; 515 int err; 516 517 lockdep_assert_held(&j->reclaim_lock); 518 519 while (1) { 520 unsigned allowed_above = allowed_above_seq; 521 unsigned allowed_below = allowed_below_seq; 522 523 if (min_any) { 524 allowed_above |= ~0; 525 allowed_below |= ~0; 526 } 527 528 if (min_key_cache) { 529 allowed_above |= 1U << JOURNAL_PIN_key_cache; 530 allowed_below |= 1U << JOURNAL_PIN_key_cache; 531 } 532 533 cond_resched(); 534 535 j->last_flushed = jiffies; 536 537 spin_lock(&j->lock); 538 pin = journal_get_next_pin(j, seq_to_flush, allowed_below, allowed_above, &seq); 539 if (pin) { 540 BUG_ON(j->flush_in_progress); 541 j->flush_in_progress = pin; 542 j->flush_in_progress_dropped = false; 543 flush_fn = pin->flush; 544 } 545 spin_unlock(&j->lock); 546 547 if (!pin) 548 break; 549 550 if (min_key_cache && pin->flush == bch2_btree_key_cache_journal_flush) 551 min_key_cache--; 552 553 if (min_any) 554 min_any--; 555 556 err = flush_fn(j, pin, seq); 557 558 spin_lock(&j->lock); 559 /* Pin might have been dropped or rearmed: */ 560 if (likely(!err && !j->flush_in_progress_dropped)) 561 list_move(&pin->list, &journal_seq_pin(j, seq)->flushed); 562 j->flush_in_progress = NULL; 563 j->flush_in_progress_dropped = false; 564 spin_unlock(&j->lock); 565 566 wake_up(&j->pin_flush_wait); 567 568 if (err) 569 break; 570 571 nr_flushed++; 572 } 573 574 return nr_flushed; 575 } 576 577 static u64 journal_seq_to_flush(struct journal *j) 578 { 579 struct bch_fs *c = container_of(j, struct bch_fs, journal); 580 u64 seq_to_flush = 0; 581 582 spin_lock(&j->lock); 583 584 for_each_rw_member(c, ca) { 585 struct journal_device *ja = &ca->journal; 586 unsigned nr_buckets, bucket_to_flush; 587 588 if (!ja->nr) 589 continue; 590 591 /* Try to keep the journal at most half full: */ 592 nr_buckets = ja->nr / 2; 593 594 nr_buckets = min(nr_buckets, ja->nr); 595 596 bucket_to_flush = (ja->cur_idx + nr_buckets) % ja->nr; 597 seq_to_flush = max(seq_to_flush, 598 ja->bucket_seq[bucket_to_flush]); 599 } 600 601 /* Also flush if the pin fifo is more than half full */ 602 seq_to_flush = max_t(s64, seq_to_flush, 603 (s64) journal_cur_seq(j) - 604 (j->pin.size >> 1)); 605 spin_unlock(&j->lock); 606 607 return seq_to_flush; 608 } 609 610 /** 611 * __bch2_journal_reclaim - free up journal buckets 612 * @j: journal object 613 * @direct: direct or background reclaim? 614 * @kicked: requested to run since we last ran? 615 * Returns: 0 on success, or -EIO if the journal has been shutdown 616 * 617 * Background journal reclaim writes out btree nodes. It should be run 618 * early enough so that we never completely run out of journal buckets. 619 * 620 * High watermarks for triggering background reclaim: 621 * - FIFO has fewer than 512 entries left 622 * - fewer than 25% journal buckets free 623 * 624 * Background reclaim runs until low watermarks are reached: 625 * - FIFO has more than 1024 entries left 626 * - more than 50% journal buckets free 627 * 628 * As long as a reclaim can complete in the time it takes to fill up 629 * 512 journal entries or 25% of all journal buckets, then 630 * journal_next_bucket() should not stall. 631 */ 632 static int __bch2_journal_reclaim(struct journal *j, bool direct, bool kicked) 633 { 634 struct bch_fs *c = container_of(j, struct bch_fs, journal); 635 bool kthread = (current->flags & PF_KTHREAD) != 0; 636 u64 seq_to_flush; 637 size_t min_nr, min_key_cache, nr_flushed; 638 unsigned flags; 639 int ret = 0; 640 641 /* 642 * We can't invoke memory reclaim while holding the reclaim_lock - 643 * journal reclaim is required to make progress for memory reclaim 644 * (cleaning the caches), so we can't get stuck in memory reclaim while 645 * we're holding the reclaim lock: 646 */ 647 lockdep_assert_held(&j->reclaim_lock); 648 flags = memalloc_noreclaim_save(); 649 650 do { 651 if (kthread && kthread_should_stop()) 652 break; 653 654 if (bch2_journal_error(j)) { 655 ret = -EIO; 656 break; 657 } 658 659 bch2_journal_do_discards(j); 660 661 seq_to_flush = journal_seq_to_flush(j); 662 min_nr = 0; 663 664 /* 665 * If it's been longer than j->reclaim_delay_ms since we last flushed, 666 * make sure to flush at least one journal pin: 667 */ 668 if (time_after(jiffies, j->last_flushed + 669 msecs_to_jiffies(c->opts.journal_reclaim_delay))) 670 min_nr = 1; 671 672 if (j->watermark != BCH_WATERMARK_stripe) 673 min_nr = 1; 674 675 if (atomic_read(&c->btree_cache.dirty) * 2 > c->btree_cache.used) 676 min_nr = 1; 677 678 min_key_cache = min(bch2_nr_btree_keys_need_flush(c), (size_t) 128); 679 680 trace_and_count(c, journal_reclaim_start, c, 681 direct, kicked, 682 min_nr, min_key_cache, 683 atomic_read(&c->btree_cache.dirty), 684 c->btree_cache.used, 685 atomic_long_read(&c->btree_key_cache.nr_dirty), 686 atomic_long_read(&c->btree_key_cache.nr_keys)); 687 688 nr_flushed = journal_flush_pins(j, seq_to_flush, 689 ~0, 0, 690 min_nr, min_key_cache); 691 692 if (direct) 693 j->nr_direct_reclaim += nr_flushed; 694 else 695 j->nr_background_reclaim += nr_flushed; 696 trace_and_count(c, journal_reclaim_finish, c, nr_flushed); 697 698 if (nr_flushed) 699 wake_up(&j->reclaim_wait); 700 } while ((min_nr || min_key_cache) && nr_flushed && !direct); 701 702 memalloc_noreclaim_restore(flags); 703 704 return ret; 705 } 706 707 int bch2_journal_reclaim(struct journal *j) 708 { 709 return __bch2_journal_reclaim(j, true, true); 710 } 711 712 static int bch2_journal_reclaim_thread(void *arg) 713 { 714 struct journal *j = arg; 715 struct bch_fs *c = container_of(j, struct bch_fs, journal); 716 unsigned long delay, now; 717 bool journal_empty; 718 int ret = 0; 719 720 set_freezable(); 721 722 j->last_flushed = jiffies; 723 724 while (!ret && !kthread_should_stop()) { 725 bool kicked = j->reclaim_kicked; 726 727 j->reclaim_kicked = false; 728 729 mutex_lock(&j->reclaim_lock); 730 ret = __bch2_journal_reclaim(j, false, kicked); 731 mutex_unlock(&j->reclaim_lock); 732 733 now = jiffies; 734 delay = msecs_to_jiffies(c->opts.journal_reclaim_delay); 735 j->next_reclaim = j->last_flushed + delay; 736 737 if (!time_in_range(j->next_reclaim, now, now + delay)) 738 j->next_reclaim = now + delay; 739 740 while (1) { 741 set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE); 742 if (kthread_should_stop()) 743 break; 744 if (j->reclaim_kicked) 745 break; 746 747 spin_lock(&j->lock); 748 journal_empty = fifo_empty(&j->pin); 749 spin_unlock(&j->lock); 750 751 if (journal_empty) 752 schedule(); 753 else if (time_after(j->next_reclaim, jiffies)) 754 schedule_timeout(j->next_reclaim - jiffies); 755 else 756 break; 757 } 758 __set_current_state(TASK_RUNNING); 759 } 760 761 return 0; 762 } 763 764 void bch2_journal_reclaim_stop(struct journal *j) 765 { 766 struct task_struct *p = j->reclaim_thread; 767 768 j->reclaim_thread = NULL; 769 770 if (p) { 771 kthread_stop(p); 772 put_task_struct(p); 773 } 774 } 775 776 int bch2_journal_reclaim_start(struct journal *j) 777 { 778 struct bch_fs *c = container_of(j, struct bch_fs, journal); 779 struct task_struct *p; 780 int ret; 781 782 if (j->reclaim_thread) 783 return 0; 784 785 p = kthread_create(bch2_journal_reclaim_thread, j, 786 "bch-reclaim/%s", c->name); 787 ret = PTR_ERR_OR_ZERO(p); 788 bch_err_msg(c, ret, "creating journal reclaim thread"); 789 if (ret) 790 return ret; 791 792 get_task_struct(p); 793 j->reclaim_thread = p; 794 wake_up_process(p); 795 return 0; 796 } 797 798 static int journal_flush_done(struct journal *j, u64 seq_to_flush, 799 bool *did_work) 800 { 801 int ret; 802 803 ret = bch2_journal_error(j); 804 if (ret) 805 return ret; 806 807 mutex_lock(&j->reclaim_lock); 808 809 if (journal_flush_pins(j, seq_to_flush, 810 (1U << JOURNAL_PIN_key_cache)| 811 (1U << JOURNAL_PIN_other), 0, 0, 0) || 812 journal_flush_pins(j, seq_to_flush, 813 (1U << JOURNAL_PIN_btree), 0, 0, 0)) 814 *did_work = true; 815 816 if (seq_to_flush > journal_cur_seq(j)) 817 bch2_journal_entry_close(j); 818 819 spin_lock(&j->lock); 820 /* 821 * If journal replay hasn't completed, the unreplayed journal entries 822 * hold refs on their corresponding sequence numbers 823 */ 824 ret = !test_bit(JOURNAL_REPLAY_DONE, &j->flags) || 825 journal_last_seq(j) > seq_to_flush || 826 !fifo_used(&j->pin); 827 828 spin_unlock(&j->lock); 829 mutex_unlock(&j->reclaim_lock); 830 831 return ret; 832 } 833 834 bool bch2_journal_flush_pins(struct journal *j, u64 seq_to_flush) 835 { 836 /* time_stats this */ 837 bool did_work = false; 838 839 if (!test_bit(JOURNAL_STARTED, &j->flags)) 840 return false; 841 842 closure_wait_event(&j->async_wait, 843 journal_flush_done(j, seq_to_flush, &did_work)); 844 845 return did_work; 846 } 847 848 int bch2_journal_flush_device_pins(struct journal *j, int dev_idx) 849 { 850 struct bch_fs *c = container_of(j, struct bch_fs, journal); 851 struct journal_entry_pin_list *p; 852 u64 iter, seq = 0; 853 int ret = 0; 854 855 spin_lock(&j->lock); 856 fifo_for_each_entry_ptr(p, &j->pin, iter) 857 if (dev_idx >= 0 858 ? bch2_dev_list_has_dev(p->devs, dev_idx) 859 : p->devs.nr < c->opts.metadata_replicas) 860 seq = iter; 861 spin_unlock(&j->lock); 862 863 bch2_journal_flush_pins(j, seq); 864 865 ret = bch2_journal_error(j); 866 if (ret) 867 return ret; 868 869 mutex_lock(&c->replicas_gc_lock); 870 bch2_replicas_gc_start(c, 1 << BCH_DATA_journal); 871 872 /* 873 * Now that we've populated replicas_gc, write to the journal to mark 874 * active journal devices. This handles the case where the journal might 875 * be empty. Otherwise we could clear all journal replicas and 876 * temporarily put the fs into an unrecoverable state. Journal recovery 877 * expects to find devices marked for journal data on unclean mount. 878 */ 879 ret = bch2_journal_meta(&c->journal); 880 if (ret) 881 goto err; 882 883 seq = 0; 884 spin_lock(&j->lock); 885 while (!ret) { 886 struct bch_replicas_padded replicas; 887 888 seq = max(seq, journal_last_seq(j)); 889 if (seq >= j->pin.back) 890 break; 891 bch2_devlist_to_replicas(&replicas.e, BCH_DATA_journal, 892 journal_seq_pin(j, seq)->devs); 893 seq++; 894 895 spin_unlock(&j->lock); 896 ret = bch2_mark_replicas(c, &replicas.e); 897 spin_lock(&j->lock); 898 } 899 spin_unlock(&j->lock); 900 err: 901 ret = bch2_replicas_gc_end(c, ret); 902 mutex_unlock(&c->replicas_gc_lock); 903 904 return ret; 905 } 906