Lines Matching +full:dc +full:- +full:to +full:- +full:dc
1 // SPDX-License-Identifier: GPL-2.0
3 * background writeback - scan btree for dirty data and write it to the backing
22 if (c->gc_after_writeback != (BCH_ENABLE_AUTO_GC) || in update_gc_after_writeback()
23 c->gc_stats.in_use < BCH_AUTO_GC_DIRTY_THRESHOLD) in update_gc_after_writeback()
26 c->gc_after_writeback |= BCH_DO_AUTO_GC; in update_gc_after_writeback()
30 static uint64_t __calc_target_rate(struct cached_dev *dc) in __calc_target_rate() argument
32 struct cache_set *c = dc->disk.c; in __calc_target_rate()
36 * flash-only devices in __calc_target_rate()
38 uint64_t cache_sectors = c->nbuckets * c->cache->sb.bucket_size - in __calc_target_rate()
39 atomic_long_read(&c->flash_dev_dirty_sectors); in __calc_target_rate()
48 div64_u64(bdev_sectors(dc->bdev) << WRITEBACK_SHARE_SHIFT, in __calc_target_rate()
49 c->cached_dev_sectors); in __calc_target_rate()
52 div_u64(cache_sectors * dc->writeback_percent, 100); in __calc_target_rate()
61 static void __update_writeback_rate(struct cached_dev *dc) in __update_writeback_rate() argument
72 * based on configured values. These are stored as inverses to in __update_writeback_rate()
73 * avoid fixed point math and to make configuration easy-- e.g. in __update_writeback_rate()
75 * attempts to write at a rate that would retire all the dirty in __update_writeback_rate()
80 * This acts as a slow, long-term average that is not subject to in __update_writeback_rate()
83 int64_t target = __calc_target_rate(dc); in __update_writeback_rate()
84 int64_t dirty = bcache_dev_sectors_dirty(&dc->disk); in __update_writeback_rate()
85 int64_t error = dirty - target; in __update_writeback_rate()
87 div_s64(error, dc->writeback_rate_p_term_inverse); in __update_writeback_rate()
91 if ((error < 0 && dc->writeback_rate_integral > 0) || in __update_writeback_rate()
93 dc->writeback_rate.next + NSEC_PER_MSEC))) { in __update_writeback_rate()
100 * It's necessary to scale this by in __update_writeback_rate()
101 * writeback_rate_update_seconds to keep the integral in __update_writeback_rate()
104 dc->writeback_rate_integral += error * in __update_writeback_rate()
105 dc->writeback_rate_update_seconds; in __update_writeback_rate()
108 integral_scaled = div_s64(dc->writeback_rate_integral, in __update_writeback_rate()
109 dc->writeback_rate_i_term_inverse); in __update_writeback_rate()
112 dc->writeback_rate_minimum, NSEC_PER_SEC); in __update_writeback_rate()
114 dc->writeback_rate_proportional = proportional_scaled; in __update_writeback_rate()
115 dc->writeback_rate_integral_scaled = integral_scaled; in __update_writeback_rate()
116 dc->writeback_rate_change = new_rate - in __update_writeback_rate()
117 atomic_long_read(&dc->writeback_rate.rate); in __update_writeback_rate()
118 atomic_long_set(&dc->writeback_rate.rate, new_rate); in __update_writeback_rate()
119 dc->writeback_rate_target = target; in __update_writeback_rate()
127 * If c->idle_counter is overflow (idel for really long time), in idle_counter_exceeded()
131 counter = atomic_inc_return(&c->idle_counter); in idle_counter_exceeded()
133 atomic_set(&c->idle_counter, 0); in idle_counter_exceeded()
137 dev_nr = atomic_read(&c->attached_dev_nr); in idle_counter_exceeded()
142 * c->idle_counter is increased by writeback thread of all in idle_counter_exceeded()
143 * attached backing devices, in order to represent a rough in idle_counter_exceeded()
147 * The following calculation equals to checking in idle_counter_exceeded()
158 * called. If all backing devices attached to the same cache set have
159 * identical dc->writeback_rate_update_seconds values, it is about 6
161 * c->at_max_writeback_rate is set to 1, and then max wrteback rate set
162 * to each dc->writeback_rate.rate.
163 * In order to avoid extra locking cost for counting exact dirty cached
164 * devices number, c->attached_dev_nr is used to calculate the idle
165 * throushold. It might be bigger if not all cached device are in write-
170 struct cached_dev *dc) in set_at_max_writeback_rate() argument
173 if (!c->idle_max_writeback_rate_enabled) in set_at_max_writeback_rate()
177 if (!c->gc_mark_valid) in set_at_max_writeback_rate()
183 if (atomic_read(&c->at_max_writeback_rate) != 1) in set_at_max_writeback_rate()
184 atomic_set(&c->at_max_writeback_rate, 1); in set_at_max_writeback_rate()
186 atomic_long_set(&dc->writeback_rate.rate, INT_MAX); in set_at_max_writeback_rate()
189 dc->writeback_rate_proportional = 0; in set_at_max_writeback_rate()
190 dc->writeback_rate_integral_scaled = 0; in set_at_max_writeback_rate()
191 dc->writeback_rate_change = 0; in set_at_max_writeback_rate()
198 !atomic_read(&c->at_max_writeback_rate)) in set_at_max_writeback_rate()
206 struct cached_dev *dc = container_of(to_delayed_work(work), in update_writeback_rate() local
209 struct cache_set *c = dc->disk.c; in update_writeback_rate()
215 set_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags); in update_writeback_rate()
223 if (!test_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags) || in update_writeback_rate()
224 test_bit(CACHE_SET_IO_DISABLE, &c->flags)) { in update_writeback_rate()
225 clear_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags); in update_writeback_rate()
231 if (atomic_read(&dc->has_dirty) && dc->writeback_percent) { in update_writeback_rate()
234 * will set writeback rate to a max number. Then it is in update_writeback_rate()
235 * unncessary to update writeback rate for an idle cache set in update_writeback_rate()
238 if (!set_at_max_writeback_rate(c, dc)) { in update_writeback_rate()
239 down_read(&dc->writeback_lock); in update_writeback_rate()
240 __update_writeback_rate(dc); in update_writeback_rate()
242 up_read(&dc->writeback_lock); in update_writeback_rate()
251 if (test_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags) && in update_writeback_rate()
252 !test_bit(CACHE_SET_IO_DISABLE, &c->flags)) { in update_writeback_rate()
253 schedule_delayed_work(&dc->writeback_rate_update, in update_writeback_rate()
254 dc->writeback_rate_update_seconds * HZ); in update_writeback_rate()
261 clear_bit(BCACHE_DEV_RATE_DW_RUNNING, &dc->disk.flags); in update_writeback_rate()
266 static unsigned int writeback_delay(struct cached_dev *dc, in writeback_delay() argument
269 if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || in writeback_delay()
270 !dc->writeback_percent) in writeback_delay()
273 return bch_next_delay(&dc->writeback_rate, sectors); in writeback_delay()
278 struct cached_dev *dc; member
285 struct dirty_io *io = w->private; in dirty_init()
286 struct bio *bio = &io->bio; in dirty_init()
288 bio_init(bio, bio->bi_inline_vecs, in dirty_init()
289 DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS)); in dirty_init()
290 if (!io->dc->writeback_percent) in dirty_init()
293 bio->bi_iter.bi_size = KEY_SIZE(&w->key) << 9; in dirty_init()
294 bio->bi_private = w; in dirty_init()
308 struct keybuf_key *w = io->bio.bi_private; in write_dirty_finish()
309 struct cached_dev *dc = io->dc; in write_dirty_finish() local
311 bio_free_pages(&io->bio); in write_dirty_finish()
314 if (KEY_DIRTY(&w->key)) { in write_dirty_finish()
321 bkey_copy(keys.top, &w->key); in write_dirty_finish()
325 for (i = 0; i < KEY_PTRS(&w->key); i++) in write_dirty_finish()
326 atomic_inc(&PTR_BUCKET(dc->disk.c, &w->key, i)->pin); in write_dirty_finish()
328 ret = bch_btree_insert(dc->disk.c, &keys, NULL, &w->key); in write_dirty_finish()
331 trace_bcache_writeback_collision(&w->key); in write_dirty_finish()
334 ? &dc->disk.c->writeback_keys_failed in write_dirty_finish()
335 : &dc->disk.c->writeback_keys_done); in write_dirty_finish()
338 bch_keybuf_del(&dc->writeback_keys, w); in write_dirty_finish()
339 up(&dc->in_flight); in write_dirty_finish()
346 struct keybuf_key *w = bio->bi_private; in dirty_endio()
347 struct dirty_io *io = w->private; in dirty_endio()
349 if (bio->bi_status) { in dirty_endio()
350 SET_KEY_DIRTY(&w->key, false); in dirty_endio()
351 bch_count_backing_io_errors(io->dc, bio); in dirty_endio()
354 closure_put(&io->cl); in dirty_endio()
360 struct keybuf_key *w = io->bio.bi_private; in write_dirty()
361 struct cached_dev *dc = io->dc; in write_dirty() local
365 if (atomic_read(&dc->writeback_sequence_next) != io->sequence) { in write_dirty()
366 /* Not our turn to write; wait for a write to complete */ in write_dirty()
367 closure_wait(&dc->writeback_ordering_wait, cl); in write_dirty()
369 if (atomic_read(&dc->writeback_sequence_next) == io->sequence) { in write_dirty()
371 * Edge case-- it happened in indeterminate order in write_dirty()
372 * relative to when we were added to wait list.. in write_dirty()
374 closure_wake_up(&dc->writeback_ordering_wait); in write_dirty()
377 continue_at(cl, write_dirty, io->dc->writeback_write_wq); in write_dirty()
381 next_sequence = io->sequence + 1; in write_dirty()
385 * If we failed to read, we should not attempt to write to the in write_dirty()
386 * backing device. Instead, immediately go to write_dirty_finish in write_dirty()
387 * to clean up. in write_dirty()
389 if (KEY_DIRTY(&w->key)) { in write_dirty()
391 bio_set_op_attrs(&io->bio, REQ_OP_WRITE, 0); in write_dirty()
392 io->bio.bi_iter.bi_sector = KEY_START(&w->key); in write_dirty()
393 bio_set_dev(&io->bio, io->dc->bdev); in write_dirty()
394 io->bio.bi_end_io = dirty_endio; in write_dirty()
396 /* I/O request sent to backing device */ in write_dirty()
397 closure_bio_submit(io->dc->disk.c, &io->bio, cl); in write_dirty()
400 atomic_set(&dc->writeback_sequence_next, next_sequence); in write_dirty()
401 closure_wake_up(&dc->writeback_ordering_wait); in write_dirty()
403 continue_at(cl, write_dirty_finish, io->dc->writeback_write_wq); in write_dirty()
408 struct keybuf_key *w = bio->bi_private; in read_dirty_endio()
409 struct dirty_io *io = w->private; in read_dirty_endio()
412 bch_count_io_errors(PTR_CACHE(io->dc->disk.c, &w->key, 0), in read_dirty_endio()
413 bio->bi_status, 1, in read_dirty_endio()
423 closure_bio_submit(io->dc->disk.c, &io->bio, cl); in read_dirty_submit()
425 continue_at(cl, write_dirty, io->dc->writeback_write_wq); in read_dirty_submit()
428 static void read_dirty(struct cached_dev *dc) in read_dirty() argument
438 BUG_ON(!llist_empty(&dc->writeback_ordering_wait.list)); in read_dirty()
439 atomic_set(&dc->writeback_sequence_next, sequence); in read_dirty()
447 next = bch_keybuf_next(&dc->writeback_keys); in read_dirty()
450 !test_bit(CACHE_SET_IO_DISABLE, &dc->disk.c->flags) && in read_dirty()
456 BUG_ON(ptr_stale(dc->disk.c, &next->key, 0)); in read_dirty()
473 * Operations are only eligible to be combined in read_dirty()
476 * TODO: add a heuristic willing to fire a in read_dirty()
477 * certain amount of non-contiguous IO per pass, in read_dirty()
481 if ((nk != 0) && bkey_cmp(&keys[nk-1]->key, in read_dirty()
482 &START_KEY(&next->key))) in read_dirty()
485 size += KEY_SIZE(&next->key); in read_dirty()
487 } while ((next = bch_keybuf_next(&dc->writeback_keys))); in read_dirty()
489 /* Now we have gathered a set of 1..5 keys to write back. */ in read_dirty()
494 DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS)), in read_dirty()
499 w->private = io; in read_dirty()
500 io->dc = dc; in read_dirty()
501 io->sequence = sequence++; in read_dirty()
504 bio_set_op_attrs(&io->bio, REQ_OP_READ, 0); in read_dirty()
505 io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0); in read_dirty()
506 bio_set_dev(&io->bio, in read_dirty()
507 PTR_CACHE(dc->disk.c, &w->key, 0)->bdev); in read_dirty()
508 io->bio.bi_end_io = read_dirty_endio; in read_dirty()
510 if (bch_bio_alloc_pages(&io->bio, GFP_KERNEL)) in read_dirty()
513 trace_bcache_writeback(&w->key); in read_dirty()
515 down(&dc->in_flight); in read_dirty()
522 closure_call(&io->cl, read_dirty_submit, NULL, &cl); in read_dirty()
525 delay = writeback_delay(dc, size); in read_dirty()
528 !test_bit(CACHE_SET_IO_DISABLE, &dc->disk.c->flags) && in read_dirty()
531 delay = writeback_delay(dc, 0); in read_dirty()
537 kfree(w->private); in read_dirty()
539 bch_keybuf_del(&dc->writeback_keys, w); in read_dirty()
543 * Wait for outstanding writeback IOs to finish (and keybuf slots to be in read_dirty()
554 struct bcache_device *d = c->devices[inode]; in bcache_dev_sectors_dirty_add()
565 if (UUID_FLASH_ONLY(&c->uuids[inode])) in bcache_dev_sectors_dirty_add()
566 atomic_long_add(nr_sectors, &c->flash_dev_dirty_sectors); in bcache_dev_sectors_dirty_add()
568 stripe_offset = offset & (d->stripe_size - 1); in bcache_dev_sectors_dirty_add()
572 d->stripe_size - stripe_offset); in bcache_dev_sectors_dirty_add()
575 s = -s; in bcache_dev_sectors_dirty_add()
577 if (stripe >= d->nr_stripes) in bcache_dev_sectors_dirty_add()
581 d->stripe_sectors_dirty + stripe); in bcache_dev_sectors_dirty_add()
582 if (sectors_dirty == d->stripe_size) in bcache_dev_sectors_dirty_add()
583 set_bit(stripe, d->full_dirty_stripes); in bcache_dev_sectors_dirty_add()
585 clear_bit(stripe, d->full_dirty_stripes); in bcache_dev_sectors_dirty_add()
587 nr_sectors -= s; in bcache_dev_sectors_dirty_add()
595 struct cached_dev *dc = container_of(buf, in dirty_pred() local
599 BUG_ON(KEY_INODE(k) != dc->disk.id); in dirty_pred()
604 static void refill_full_stripes(struct cached_dev *dc) in refill_full_stripes() argument
606 struct keybuf *buf = &dc->writeback_keys; in refill_full_stripes()
611 stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned)); in refill_full_stripes()
618 stripe = find_next_bit(dc->disk.full_dirty_stripes, in refill_full_stripes()
619 dc->disk.nr_stripes, stripe); in refill_full_stripes()
621 if (stripe == dc->disk.nr_stripes) in refill_full_stripes()
624 next_stripe = find_next_zero_bit(dc->disk.full_dirty_stripes, in refill_full_stripes()
625 dc->disk.nr_stripes, stripe); in refill_full_stripes()
627 buf->last_scanned = KEY(dc->disk.id, in refill_full_stripes()
628 stripe * dc->disk.stripe_size, 0); in refill_full_stripes()
630 bch_refill_keybuf(dc->disk.c, buf, in refill_full_stripes()
631 &KEY(dc->disk.id, in refill_full_stripes()
632 next_stripe * dc->disk.stripe_size, 0), in refill_full_stripes()
635 if (array_freelist_empty(&buf->freelist)) in refill_full_stripes()
643 if (stripe == dc->disk.nr_stripes) { in refill_full_stripes()
653 static bool refill_dirty(struct cached_dev *dc) in refill_dirty() argument
655 struct keybuf *buf = &dc->writeback_keys; in refill_dirty()
656 struct bkey start = KEY(dc->disk.id, 0, 0); in refill_dirty()
657 struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0); in refill_dirty()
661 * make sure keybuf pos is inside the range for this disk - at bringup in refill_dirty()
665 if (bkey_cmp(&buf->last_scanned, &start) < 0 || in refill_dirty()
666 bkey_cmp(&buf->last_scanned, &end) > 0) in refill_dirty()
667 buf->last_scanned = start; in refill_dirty()
669 if (dc->partial_stripes_expensive) { in refill_dirty()
670 refill_full_stripes(dc); in refill_dirty()
671 if (array_freelist_empty(&buf->freelist)) in refill_dirty()
675 start_pos = buf->last_scanned; in refill_dirty()
676 bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred); in refill_dirty()
678 if (bkey_cmp(&buf->last_scanned, &end) < 0) in refill_dirty()
682 * If we get to the end start scanning again from the beginning, and in refill_dirty()
683 * only scan up to where we initially started scanning from: in refill_dirty()
685 buf->last_scanned = start; in refill_dirty()
686 bch_refill_keybuf(dc->disk.c, buf, &start_pos, dirty_pred); in refill_dirty()
688 return bkey_cmp(&buf->last_scanned, &start_pos) >= 0; in refill_dirty()
693 struct cached_dev *dc = arg; in bch_writeback_thread() local
694 struct cache_set *c = dc->disk.c; in bch_writeback_thread()
697 bch_ratelimit_reset(&dc->writeback_rate); in bch_writeback_thread()
700 !test_bit(CACHE_SET_IO_DISABLE, &c->flags)) { in bch_writeback_thread()
701 down_write(&dc->writeback_lock); in bch_writeback_thread()
705 * to perform writeback. Otherwise, if no dirty data on cache, in bch_writeback_thread()
708 * to wake up it. in bch_writeback_thread()
710 if (!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) && in bch_writeback_thread()
711 (!atomic_read(&dc->has_dirty) || !dc->writeback_running)) { in bch_writeback_thread()
712 up_write(&dc->writeback_lock); in bch_writeback_thread()
715 test_bit(CACHE_SET_IO_DISABLE, &c->flags)) { in bch_writeback_thread()
725 searched_full_index = refill_dirty(dc); in bch_writeback_thread()
728 RB_EMPTY_ROOT(&dc->writeback_keys.keys)) { in bch_writeback_thread()
729 atomic_set(&dc->has_dirty, 0); in bch_writeback_thread()
730 SET_BDEV_STATE(&dc->sb, BDEV_STATE_CLEAN); in bch_writeback_thread()
731 bch_write_bdev_super(dc, NULL); in bch_writeback_thread()
738 if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) { in bch_writeback_thread()
739 up_write(&dc->writeback_lock); in bch_writeback_thread()
754 if (c->gc_after_writeback == in bch_writeback_thread()
756 c->gc_after_writeback &= ~BCH_DO_AUTO_GC; in bch_writeback_thread()
761 up_write(&dc->writeback_lock); in bch_writeback_thread()
763 read_dirty(dc); in bch_writeback_thread()
766 unsigned int delay = dc->writeback_delay * HZ; in bch_writeback_thread()
770 !test_bit(CACHE_SET_IO_DISABLE, &c->flags) && in bch_writeback_thread()
771 !test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) in bch_writeback_thread()
774 bch_ratelimit_reset(&dc->writeback_rate); in bch_writeback_thread()
778 if (dc->writeback_write_wq) { in bch_writeback_thread()
779 flush_workqueue(dc->writeback_write_wq); in bch_writeback_thread()
780 destroy_workqueue(dc->writeback_write_wq); in bch_writeback_thread()
782 cached_dev_put(dc); in bch_writeback_thread()
802 if (KEY_INODE(k) > op->inode) in sectors_dirty_init_fn()
806 bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k), in sectors_dirty_init_fn()
809 op->count++; in sectors_dirty_init_fn()
810 if (!(op->count % INIT_KEYS_EACH_TIME)) in sectors_dirty_init_fn()
823 bch_btree_op_init(&op.op, -1); in bch_root_node_dirty_init()
824 op.inode = d->id; in bch_root_node_dirty_init()
829 c->root, in bch_root_node_dirty_init()
838 * The op may be added to cache_set's btree_cache_wait in bch_root_node_dirty_init()
845 finish_wait(&c->btree_cache_wait, &(&op.op)->wait); in bch_root_node_dirty_init()
853 struct bch_dirty_init_state *state = info->state; in bch_dirty_init_thread()
854 struct cache_set *c = state->c; in bch_dirty_init_thread()
862 bch_btree_iter_init(&c->root->keys, &iter, NULL); in bch_dirty_init_thread()
863 k = bch_btree_iter_next_filter(&iter, &c->root->keys, bch_ptr_bad); in bch_dirty_init_thread()
869 spin_lock(&state->idx_lock); in bch_dirty_init_thread()
870 cur_idx = state->key_idx; in bch_dirty_init_thread()
871 state->key_idx++; in bch_dirty_init_thread()
872 spin_unlock(&state->idx_lock); in bch_dirty_init_thread()
874 skip_nr = cur_idx - prev_idx; in bch_dirty_init_thread()
878 &c->root->keys, in bch_dirty_init_thread()
883 atomic_set(&state->enough, 1); in bch_dirty_init_thread()
884 /* Update state->enough earlier */ in bch_dirty_init_thread()
888 skip_nr--; in bch_dirty_init_thread()
892 if (bch_root_node_dirty_init(c, state->d, p) < 0) in bch_dirty_init_thread()
901 /* In order to wake up state->wait in time */ in bch_dirty_init_thread()
903 if (atomic_dec_and_test(&state->started)) in bch_dirty_init_thread()
904 wake_up(&state->wait); in bch_dirty_init_thread()
928 struct cache_set *c = d->c; in bch_sectors_dirty_init()
932 b = c->root; in bch_sectors_dirty_init()
933 rw_lock(0, b, b->level); in bch_sectors_dirty_init()
934 if (b != c->root) { in bch_sectors_dirty_init()
940 if (c->root->level == 0) { in bch_sectors_dirty_init()
941 bch_btree_op_init(&op.op, -1); in bch_sectors_dirty_init()
942 op.inode = d->id; in bch_sectors_dirty_init()
945 for_each_key_filter(&c->root->keys, in bch_sectors_dirty_init()
949 sectors_dirty_init_fn(&op.op, c->root, k); in bch_sectors_dirty_init()
978 pr_err("fails to run thread bch_dirty_init[%d]\n", i); in bch_sectors_dirty_init()
980 for (--i; i >= 0; i--) in bch_sectors_dirty_init()
987 /* Must wait for all threads to stop. */ in bch_sectors_dirty_init()
992 void bch_cached_dev_writeback_init(struct cached_dev *dc) in bch_cached_dev_writeback_init() argument
994 sema_init(&dc->in_flight, 64); in bch_cached_dev_writeback_init()
995 init_rwsem(&dc->writeback_lock); in bch_cached_dev_writeback_init()
996 bch_keybuf_init(&dc->writeback_keys); in bch_cached_dev_writeback_init()
998 dc->writeback_metadata = true; in bch_cached_dev_writeback_init()
999 dc->writeback_running = false; in bch_cached_dev_writeback_init()
1000 dc->writeback_percent = 10; in bch_cached_dev_writeback_init()
1001 dc->writeback_delay = 30; in bch_cached_dev_writeback_init()
1002 atomic_long_set(&dc->writeback_rate.rate, 1024); in bch_cached_dev_writeback_init()
1003 dc->writeback_rate_minimum = 8; in bch_cached_dev_writeback_init()
1005 dc->writeback_rate_update_seconds = WRITEBACK_RATE_UPDATE_SECS_DEFAULT; in bch_cached_dev_writeback_init()
1006 dc->writeback_rate_p_term_inverse = 40; in bch_cached_dev_writeback_init()
1007 dc->writeback_rate_i_term_inverse = 10000; in bch_cached_dev_writeback_init()
1009 WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)); in bch_cached_dev_writeback_init()
1010 INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate); in bch_cached_dev_writeback_init()
1013 int bch_cached_dev_writeback_start(struct cached_dev *dc) in bch_cached_dev_writeback_start() argument
1015 dc->writeback_write_wq = alloc_workqueue("bcache_writeback_wq", in bch_cached_dev_writeback_start()
1017 if (!dc->writeback_write_wq) in bch_cached_dev_writeback_start()
1018 return -ENOMEM; in bch_cached_dev_writeback_start()
1020 cached_dev_get(dc); in bch_cached_dev_writeback_start()
1021 dc->writeback_thread = kthread_create(bch_writeback_thread, dc, in bch_cached_dev_writeback_start()
1023 if (IS_ERR(dc->writeback_thread)) { in bch_cached_dev_writeback_start()
1024 cached_dev_put(dc); in bch_cached_dev_writeback_start()
1025 destroy_workqueue(dc->writeback_write_wq); in bch_cached_dev_writeback_start()
1026 return PTR_ERR(dc->writeback_thread); in bch_cached_dev_writeback_start()
1028 dc->writeback_running = true; in bch_cached_dev_writeback_start()
1030 WARN_ON(test_and_set_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)); in bch_cached_dev_writeback_start()
1031 schedule_delayed_work(&dc->writeback_rate_update, in bch_cached_dev_writeback_start()
1032 dc->writeback_rate_update_seconds * HZ); in bch_cached_dev_writeback_start()
1034 bch_writeback_queue(dc); in bch_cached_dev_writeback_start()