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