blob: f1986bcd1bf05e1058e26946c600a6e2c1f5991d [file] [log] [blame]
Kent Overstreetcafe5632013-03-23 16:11:31 -07001/*
2 * background writeback - scan btree for dirty data and write it to the backing
3 * device
4 *
5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
6 * Copyright 2012 Google, Inc.
7 */
8
9#include "bcache.h"
10#include "btree.h"
11#include "debug.h"
Kent Overstreet279afba2013-06-05 06:21:07 -070012#include "writeback.h"
Kent Overstreetcafe5632013-03-23 16:11:31 -070013
Kent Overstreet5e6926d2013-07-24 17:50:06 -070014#include <linux/delay.h>
15#include <linux/freezer.h>
16#include <linux/kthread.h>
Kent Overstreetc37511b2013-04-26 15:39:55 -070017#include <trace/events/bcache.h>
18
Kent Overstreetcafe5632013-03-23 16:11:31 -070019/* Rate limiting */
20
21static void __update_writeback_rate(struct cached_dev *dc)
22{
23 struct cache_set *c = dc->disk.c;
24 uint64_t cache_sectors = c->nbuckets * c->sb.bucket_size;
25 uint64_t cache_dirty_target =
26 div_u64(cache_sectors * dc->writeback_percent, 100);
27
28 int64_t target = div64_u64(cache_dirty_target * bdev_sectors(dc->bdev),
29 c->cached_dev_sectors);
30
31 /* PD controller */
32
Kent Overstreet279afba2013-06-05 06:21:07 -070033 int64_t dirty = bcache_dev_sectors_dirty(&dc->disk);
Kent Overstreetcafe5632013-03-23 16:11:31 -070034 int64_t derivative = dirty - dc->disk.sectors_dirty_last;
Kent Overstreet16749c22013-11-11 13:58:34 -080035 int64_t proportional = dirty - target;
36 int64_t change;
Kent Overstreetcafe5632013-03-23 16:11:31 -070037
38 dc->disk.sectors_dirty_last = dirty;
39
Kent Overstreet16749c22013-11-11 13:58:34 -080040 /* Scale to sectors per second */
41
42 proportional *= dc->writeback_rate_update_seconds;
43 proportional = div_s64(proportional, dc->writeback_rate_p_term_inverse);
44
45 derivative = div_s64(derivative, dc->writeback_rate_update_seconds);
Kent Overstreetcafe5632013-03-23 16:11:31 -070046
47 derivative = ewma_add(dc->disk.sectors_dirty_derivative, derivative,
Kent Overstreet16749c22013-11-11 13:58:34 -080048 (dc->writeback_rate_d_term /
49 dc->writeback_rate_update_seconds) ?: 1, 0);
Kent Overstreetcafe5632013-03-23 16:11:31 -070050
Kent Overstreet16749c22013-11-11 13:58:34 -080051 derivative *= dc->writeback_rate_d_term;
52 derivative = div_s64(derivative, dc->writeback_rate_p_term_inverse);
Kent Overstreetcafe5632013-03-23 16:11:31 -070053
Kent Overstreet16749c22013-11-11 13:58:34 -080054 change = proportional + derivative;
Kent Overstreetcafe5632013-03-23 16:11:31 -070055
56 /* Don't increase writeback rate if the device isn't keeping up */
57 if (change > 0 &&
58 time_after64(local_clock(),
Kent Overstreet16749c22013-11-11 13:58:34 -080059 dc->writeback_rate.next + NSEC_PER_MSEC))
Kent Overstreetcafe5632013-03-23 16:11:31 -070060 change = 0;
61
62 dc->writeback_rate.rate =
Kent Overstreet16749c22013-11-11 13:58:34 -080063 clamp_t(int64_t, (int64_t) dc->writeback_rate.rate + change,
Kent Overstreetcafe5632013-03-23 16:11:31 -070064 1, NSEC_PER_MSEC);
Kent Overstreet16749c22013-11-11 13:58:34 -080065
66 dc->writeback_rate_proportional = proportional;
Kent Overstreetcafe5632013-03-23 16:11:31 -070067 dc->writeback_rate_derivative = derivative;
68 dc->writeback_rate_change = change;
69 dc->writeback_rate_target = target;
Kent Overstreetcafe5632013-03-23 16:11:31 -070070}
71
72static void update_writeback_rate(struct work_struct *work)
73{
74 struct cached_dev *dc = container_of(to_delayed_work(work),
75 struct cached_dev,
76 writeback_rate_update);
77
78 down_read(&dc->writeback_lock);
79
80 if (atomic_read(&dc->has_dirty) &&
81 dc->writeback_percent)
82 __update_writeback_rate(dc);
83
84 up_read(&dc->writeback_lock);
Kent Overstreet5e6926d2013-07-24 17:50:06 -070085
86 schedule_delayed_work(&dc->writeback_rate_update,
87 dc->writeback_rate_update_seconds * HZ);
Kent Overstreetcafe5632013-03-23 16:11:31 -070088}
89
90static unsigned writeback_delay(struct cached_dev *dc, unsigned sectors)
91{
Kent Overstreetc4d951d2013-08-21 17:49:09 -070092 if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) ||
Kent Overstreetcafe5632013-03-23 16:11:31 -070093 !dc->writeback_percent)
94 return 0;
95
Kent Overstreet16749c22013-11-11 13:58:34 -080096 return bch_next_delay(&dc->writeback_rate, sectors);
Kent Overstreetcafe5632013-03-23 16:11:31 -070097}
98
Kent Overstreet5e6926d2013-07-24 17:50:06 -070099struct dirty_io {
100 struct closure cl;
101 struct cached_dev *dc;
102 struct bio bio;
103};
Kent Overstreet72c27062013-06-05 06:24:39 -0700104
Kent Overstreetcafe5632013-03-23 16:11:31 -0700105static void dirty_init(struct keybuf_key *w)
106{
107 struct dirty_io *io = w->private;
108 struct bio *bio = &io->bio;
109
110 bio_init(bio);
111 if (!io->dc->writeback_percent)
112 bio_set_prio(bio, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0));
113
Kent Overstreet4f024f32013-10-11 15:44:27 -0700114 bio->bi_iter.bi_size = KEY_SIZE(&w->key) << 9;
Kent Overstreetcafe5632013-03-23 16:11:31 -0700115 bio->bi_max_vecs = DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS);
116 bio->bi_private = w;
117 bio->bi_io_vec = bio->bi_inline_vecs;
Kent Overstreet169ef1c2013-03-28 12:50:55 -0600118 bch_bio_map(bio, NULL);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700119}
120
Kent Overstreetcafe5632013-03-23 16:11:31 -0700121static void dirty_io_destructor(struct closure *cl)
122{
123 struct dirty_io *io = container_of(cl, struct dirty_io, cl);
124 kfree(io);
125}
126
127static void write_dirty_finish(struct closure *cl)
128{
129 struct dirty_io *io = container_of(cl, struct dirty_io, cl);
130 struct keybuf_key *w = io->bio.bi_private;
131 struct cached_dev *dc = io->dc;
Kent Overstreet8e51e412013-06-06 18:15:57 -0700132 struct bio_vec *bv;
133 int i;
Kent Overstreetcafe5632013-03-23 16:11:31 -0700134
Kent Overstreet8e51e412013-06-06 18:15:57 -0700135 bio_for_each_segment_all(bv, &io->bio, i)
Kent Overstreetcafe5632013-03-23 16:11:31 -0700136 __free_page(bv->bv_page);
137
138 /* This is kind of a dumb way of signalling errors. */
139 if (KEY_DIRTY(&w->key)) {
Kent Overstreet6054c6d2013-07-24 18:06:22 -0700140 int ret;
Kent Overstreetcc7b8812013-07-24 18:07:22 -0700141 unsigned i;
142 struct keylist keys;
Kent Overstreet0b932072013-07-24 17:26:51 -0700143
Kent Overstreet0b932072013-07-24 17:26:51 -0700144 bch_keylist_init(&keys);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700145
Kent Overstreet1b207d82013-09-10 18:52:54 -0700146 bkey_copy(keys.top, &w->key);
147 SET_KEY_DIRTY(keys.top, false);
148 bch_keylist_push(&keys);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700149
150 for (i = 0; i < KEY_PTRS(&w->key); i++)
151 atomic_inc(&PTR_BUCKET(dc->disk.c, &w->key, i)->pin);
152
Kent Overstreetcc7b8812013-07-24 18:07:22 -0700153 ret = bch_btree_insert(dc->disk.c, &keys, NULL, &w->key);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700154
Kent Overstreet6054c6d2013-07-24 18:06:22 -0700155 if (ret)
Kent Overstreetc37511b2013-04-26 15:39:55 -0700156 trace_bcache_writeback_collision(&w->key);
157
Kent Overstreet6054c6d2013-07-24 18:06:22 -0700158 atomic_long_inc(ret
Kent Overstreetcafe5632013-03-23 16:11:31 -0700159 ? &dc->disk.c->writeback_keys_failed
160 : &dc->disk.c->writeback_keys_done);
161 }
162
163 bch_keybuf_del(&dc->writeback_keys, w);
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700164 up(&dc->in_flight);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700165
166 closure_return_with_destructor(cl, dirty_io_destructor);
167}
168
169static void dirty_endio(struct bio *bio, int error)
170{
171 struct keybuf_key *w = bio->bi_private;
172 struct dirty_io *io = w->private;
173
174 if (error)
175 SET_KEY_DIRTY(&w->key, false);
176
177 closure_put(&io->cl);
178}
179
180static void write_dirty(struct closure *cl)
181{
182 struct dirty_io *io = container_of(cl, struct dirty_io, cl);
183 struct keybuf_key *w = io->bio.bi_private;
184
185 dirty_init(w);
186 io->bio.bi_rw = WRITE;
Kent Overstreet4f024f32013-10-11 15:44:27 -0700187 io->bio.bi_iter.bi_sector = KEY_START(&w->key);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700188 io->bio.bi_bdev = io->dc->bdev;
189 io->bio.bi_end_io = dirty_endio;
190
Kent Overstreetcafe5632013-03-23 16:11:31 -0700191 closure_bio_submit(&io->bio, cl, &io->dc->disk);
192
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700193 continue_at(cl, write_dirty_finish, system_wq);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700194}
195
196static void read_dirty_endio(struct bio *bio, int error)
197{
198 struct keybuf_key *w = bio->bi_private;
199 struct dirty_io *io = w->private;
200
201 bch_count_io_errors(PTR_CACHE(io->dc->disk.c, &w->key, 0),
202 error, "reading dirty data from cache");
203
204 dirty_endio(bio, error);
205}
206
207static void read_dirty_submit(struct closure *cl)
208{
209 struct dirty_io *io = container_of(cl, struct dirty_io, cl);
210
Kent Overstreetcafe5632013-03-23 16:11:31 -0700211 closure_bio_submit(&io->bio, cl, &io->dc->disk);
212
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700213 continue_at(cl, write_dirty, system_wq);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700214}
215
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700216static void read_dirty(struct cached_dev *dc)
Kent Overstreetcafe5632013-03-23 16:11:31 -0700217{
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700218 unsigned delay = 0;
Kent Overstreetcafe5632013-03-23 16:11:31 -0700219 struct keybuf_key *w;
220 struct dirty_io *io;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700221 struct closure cl;
222
223 closure_init_stack(&cl);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700224
225 /*
226 * XXX: if we error, background writeback just spins. Should use some
227 * mempools.
228 */
229
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700230 while (!kthread_should_stop()) {
231 try_to_freeze();
232
Kent Overstreetcafe5632013-03-23 16:11:31 -0700233 w = bch_keybuf_next(&dc->writeback_keys);
234 if (!w)
235 break;
236
237 BUG_ON(ptr_stale(dc->disk.c, &w->key, 0));
238
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700239 if (KEY_START(&w->key) != dc->last_read ||
240 jiffies_to_msecs(delay) > 50)
241 while (!kthread_should_stop() && delay)
Slava Pestov9e5c3532014-05-01 13:48:57 -0700242 delay = schedule_timeout_interruptible(delay);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700243
244 dc->last_read = KEY_OFFSET(&w->key);
245
246 io = kzalloc(sizeof(struct dirty_io) + sizeof(struct bio_vec)
247 * DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS),
248 GFP_KERNEL);
249 if (!io)
250 goto err;
251
252 w->private = io;
253 io->dc = dc;
254
255 dirty_init(w);
Kent Overstreet4f024f32013-10-11 15:44:27 -0700256 io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700257 io->bio.bi_bdev = PTR_CACHE(dc->disk.c,
258 &w->key, 0)->bdev;
259 io->bio.bi_rw = READ;
260 io->bio.bi_end_io = read_dirty_endio;
261
Kent Overstreet8e51e412013-06-06 18:15:57 -0700262 if (bio_alloc_pages(&io->bio, GFP_KERNEL))
Kent Overstreetcafe5632013-03-23 16:11:31 -0700263 goto err_free;
264
Kent Overstreetc37511b2013-04-26 15:39:55 -0700265 trace_bcache_writeback(&w->key);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700266
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700267 down(&dc->in_flight);
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700268 closure_call(&io->cl, read_dirty_submit, NULL, &cl);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700269
270 delay = writeback_delay(dc, KEY_SIZE(&w->key));
Kent Overstreetcafe5632013-03-23 16:11:31 -0700271 }
272
273 if (0) {
274err_free:
275 kfree(w->private);
276err:
277 bch_keybuf_del(&dc->writeback_keys, w);
278 }
279
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700280 /*
281 * Wait for outstanding writeback IOs to finish (and keybuf slots to be
282 * freed) before refilling again
283 */
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700284 closure_sync(&cl);
285}
286
287/* Scan for dirty data */
288
289void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode,
290 uint64_t offset, int nr_sectors)
291{
292 struct bcache_device *d = c->devices[inode];
Kent Overstreet48a915a2013-10-31 15:43:22 -0700293 unsigned stripe_offset, stripe, sectors_dirty;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700294
295 if (!d)
296 return;
297
Kent Overstreet48a915a2013-10-31 15:43:22 -0700298 stripe = offset_to_stripe(d, offset);
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700299 stripe_offset = offset & (d->stripe_size - 1);
300
301 while (nr_sectors) {
302 int s = min_t(unsigned, abs(nr_sectors),
303 d->stripe_size - stripe_offset);
304
305 if (nr_sectors < 0)
306 s = -s;
307
Kent Overstreet48a915a2013-10-31 15:43:22 -0700308 if (stripe >= d->nr_stripes)
309 return;
310
311 sectors_dirty = atomic_add_return(s,
312 d->stripe_sectors_dirty + stripe);
313 if (sectors_dirty == d->stripe_size)
314 set_bit(stripe, d->full_dirty_stripes);
315 else
316 clear_bit(stripe, d->full_dirty_stripes);
317
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700318 nr_sectors -= s;
319 stripe_offset = 0;
320 stripe++;
321 }
322}
323
324static bool dirty_pred(struct keybuf *buf, struct bkey *k)
325{
326 return KEY_DIRTY(k);
327}
328
Kent Overstreet48a915a2013-10-31 15:43:22 -0700329static void refill_full_stripes(struct cached_dev *dc)
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700330{
Kent Overstreet48a915a2013-10-31 15:43:22 -0700331 struct keybuf *buf = &dc->writeback_keys;
332 unsigned start_stripe, stripe, next_stripe;
333 bool wrapped = false;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700334
Kent Overstreet48a915a2013-10-31 15:43:22 -0700335 stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned));
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700336
Kent Overstreet48a915a2013-10-31 15:43:22 -0700337 if (stripe >= dc->disk.nr_stripes)
338 stripe = 0;
339
340 start_stripe = stripe;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700341
342 while (1) {
Kent Overstreet48a915a2013-10-31 15:43:22 -0700343 stripe = find_next_bit(dc->disk.full_dirty_stripes,
344 dc->disk.nr_stripes, stripe);
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700345
Kent Overstreet48a915a2013-10-31 15:43:22 -0700346 if (stripe == dc->disk.nr_stripes)
347 goto next;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700348
Kent Overstreet48a915a2013-10-31 15:43:22 -0700349 next_stripe = find_next_zero_bit(dc->disk.full_dirty_stripes,
350 dc->disk.nr_stripes, stripe);
351
352 buf->last_scanned = KEY(dc->disk.id,
353 stripe * dc->disk.stripe_size, 0);
354
355 bch_refill_keybuf(dc->disk.c, buf,
356 &KEY(dc->disk.id,
357 next_stripe * dc->disk.stripe_size, 0),
358 dirty_pred);
359
360 if (array_freelist_empty(&buf->freelist))
361 return;
362
363 stripe = next_stripe;
364next:
365 if (wrapped && stripe > start_stripe)
366 return;
367
368 if (stripe == dc->disk.nr_stripes) {
369 stripe = 0;
370 wrapped = true;
371 }
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700372 }
373}
374
375static bool refill_dirty(struct cached_dev *dc)
376{
377 struct keybuf *buf = &dc->writeback_keys;
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700378 struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0);
Kent Overstreet48a915a2013-10-31 15:43:22 -0700379 bool searched_from_start = false;
380
381 if (dc->partial_stripes_expensive) {
382 refill_full_stripes(dc);
383 if (array_freelist_empty(&buf->freelist))
384 return false;
385 }
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700386
387 if (bkey_cmp(&buf->last_scanned, &end) >= 0) {
388 buf->last_scanned = KEY(dc->disk.id, 0, 0);
389 searched_from_start = true;
390 }
391
Kent Overstreet48a915a2013-10-31 15:43:22 -0700392 bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred);
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700393
394 return bkey_cmp(&buf->last_scanned, &end) >= 0 && searched_from_start;
395}
396
397static int bch_writeback_thread(void *arg)
398{
399 struct cached_dev *dc = arg;
400 bool searched_full_index;
401
402 while (!kthread_should_stop()) {
403 down_write(&dc->writeback_lock);
404 if (!atomic_read(&dc->has_dirty) ||
Kent Overstreetc4d951d2013-08-21 17:49:09 -0700405 (!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) &&
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700406 !dc->writeback_running)) {
407 up_write(&dc->writeback_lock);
408 set_current_state(TASK_INTERRUPTIBLE);
409
410 if (kthread_should_stop())
411 return 0;
412
413 try_to_freeze();
414 schedule();
415 continue;
416 }
417
418 searched_full_index = refill_dirty(dc);
419
420 if (searched_full_index &&
421 RB_EMPTY_ROOT(&dc->writeback_keys.keys)) {
422 atomic_set(&dc->has_dirty, 0);
423 cached_dev_put(dc);
424 SET_BDEV_STATE(&dc->sb, BDEV_STATE_CLEAN);
425 bch_write_bdev_super(dc, NULL);
426 }
427
428 up_write(&dc->writeback_lock);
429
430 bch_ratelimit_reset(&dc->writeback_rate);
431 read_dirty(dc);
432
433 if (searched_full_index) {
434 unsigned delay = dc->writeback_delay * HZ;
435
436 while (delay &&
437 !kthread_should_stop() &&
Kent Overstreetc4d951d2013-08-21 17:49:09 -0700438 !test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags))
Slava Pestov9e5c3532014-05-01 13:48:57 -0700439 delay = schedule_timeout_interruptible(delay);
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700440 }
441 }
442
443 return 0;
Kent Overstreetcafe5632013-03-23 16:11:31 -0700444}
445
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700446/* Init */
447
Kent Overstreetc18536a2013-07-24 17:44:17 -0700448struct sectors_dirty_init {
449 struct btree_op op;
450 unsigned inode;
451};
452
453static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b,
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700454 struct bkey *k)
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700455{
Kent Overstreetc18536a2013-07-24 17:44:17 -0700456 struct sectors_dirty_init *op = container_of(_op,
457 struct sectors_dirty_init, op);
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700458 if (KEY_INODE(k) > op->inode)
459 return MAP_DONE;
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700460
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700461 if (KEY_DIRTY(k))
462 bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k),
463 KEY_START(k), KEY_SIZE(k));
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700464
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700465 return MAP_CONTINUE;
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700466}
467
468void bch_sectors_dirty_init(struct cached_dev *dc)
469{
Kent Overstreetc18536a2013-07-24 17:44:17 -0700470 struct sectors_dirty_init op;
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700471
Kent Overstreetb54d6932013-07-24 18:04:18 -0700472 bch_btree_op_init(&op.op, -1);
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700473 op.inode = dc->disk.id;
474
Kent Overstreetc18536a2013-07-24 17:44:17 -0700475 bch_btree_map_keys(&op.op, dc->disk.c, &KEY(op.inode, 0, 0),
Kent Overstreet48dad8b2013-09-10 18:48:51 -0700476 sectors_dirty_init_fn, 0);
Kent Overstreet16749c22013-11-11 13:58:34 -0800477
478 dc->disk.sectors_dirty_last = bcache_dev_sectors_dirty(&dc->disk);
Kent Overstreet444fc0b2013-05-11 17:07:26 -0700479}
480
Slava Pestov9e5c3532014-05-01 13:48:57 -0700481void bch_cached_dev_writeback_init(struct cached_dev *dc)
Kent Overstreetcafe5632013-03-23 16:11:31 -0700482{
Kent Overstreetc2a4f312013-09-23 23:17:31 -0700483 sema_init(&dc->in_flight, 64);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700484 init_rwsem(&dc->writeback_lock);
Kent Overstreet72c27062013-06-05 06:24:39 -0700485 bch_keybuf_init(&dc->writeback_keys);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700486
487 dc->writeback_metadata = true;
488 dc->writeback_running = true;
489 dc->writeback_percent = 10;
490 dc->writeback_delay = 30;
491 dc->writeback_rate.rate = 1024;
492
Kent Overstreet16749c22013-11-11 13:58:34 -0800493 dc->writeback_rate_update_seconds = 5;
494 dc->writeback_rate_d_term = 30;
495 dc->writeback_rate_p_term_inverse = 6000;
Kent Overstreetcafe5632013-03-23 16:11:31 -0700496
Slava Pestov9e5c3532014-05-01 13:48:57 -0700497 INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate);
498}
499
500int bch_cached_dev_writeback_start(struct cached_dev *dc)
501{
Kent Overstreet5e6926d2013-07-24 17:50:06 -0700502 dc->writeback_thread = kthread_create(bch_writeback_thread, dc,
503 "bcache_writeback");
504 if (IS_ERR(dc->writeback_thread))
505 return PTR_ERR(dc->writeback_thread);
506
Kent Overstreetcafe5632013-03-23 16:11:31 -0700507 schedule_delayed_work(&dc->writeback_rate_update,
508 dc->writeback_rate_update_seconds * HZ);
Kent Overstreetcafe5632013-03-23 16:11:31 -0700509
Slava Pestov9e5c3532014-05-01 13:48:57 -0700510 bch_writeback_queue(dc);
511
Kent Overstreetcafe5632013-03-23 16:11:31 -0700512 return 0;
513}