Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 1 | /* |
| 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 Overstreet | 279afba | 2013-06-05 06:21:07 -0700 | [diff] [blame] | 12 | #include "writeback.h" |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 13 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 14 | #include <linux/delay.h> |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 15 | #include <linux/kthread.h> |
Kent Overstreet | c37511b | 2013-04-26 15:39:55 -0700 | [diff] [blame] | 16 | #include <trace/events/bcache.h> |
| 17 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 18 | /* Rate limiting */ |
| 19 | |
| 20 | static void __update_writeback_rate(struct cached_dev *dc) |
| 21 | { |
| 22 | struct cache_set *c = dc->disk.c; |
| 23 | uint64_t cache_sectors = c->nbuckets * c->sb.bucket_size; |
| 24 | uint64_t cache_dirty_target = |
| 25 | div_u64(cache_sectors * dc->writeback_percent, 100); |
| 26 | |
| 27 | int64_t target = div64_u64(cache_dirty_target * bdev_sectors(dc->bdev), |
| 28 | c->cached_dev_sectors); |
| 29 | |
| 30 | /* PD controller */ |
| 31 | |
Kent Overstreet | 279afba | 2013-06-05 06:21:07 -0700 | [diff] [blame] | 32 | int64_t dirty = bcache_dev_sectors_dirty(&dc->disk); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 33 | int64_t derivative = dirty - dc->disk.sectors_dirty_last; |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 34 | int64_t proportional = dirty - target; |
| 35 | int64_t change; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 36 | |
| 37 | dc->disk.sectors_dirty_last = dirty; |
| 38 | |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 39 | /* Scale to sectors per second */ |
| 40 | |
| 41 | proportional *= dc->writeback_rate_update_seconds; |
| 42 | proportional = div_s64(proportional, dc->writeback_rate_p_term_inverse); |
| 43 | |
| 44 | derivative = div_s64(derivative, dc->writeback_rate_update_seconds); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 45 | |
| 46 | derivative = ewma_add(dc->disk.sectors_dirty_derivative, derivative, |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 47 | (dc->writeback_rate_d_term / |
| 48 | dc->writeback_rate_update_seconds) ?: 1, 0); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 49 | |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 50 | derivative *= dc->writeback_rate_d_term; |
| 51 | derivative = div_s64(derivative, dc->writeback_rate_p_term_inverse); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 52 | |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 53 | change = proportional + derivative; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 54 | |
| 55 | /* Don't increase writeback rate if the device isn't keeping up */ |
| 56 | if (change > 0 && |
| 57 | time_after64(local_clock(), |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 58 | dc->writeback_rate.next + NSEC_PER_MSEC)) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 59 | change = 0; |
| 60 | |
| 61 | dc->writeback_rate.rate = |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 62 | clamp_t(int64_t, (int64_t) dc->writeback_rate.rate + change, |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 63 | 1, NSEC_PER_MSEC); |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 64 | |
| 65 | dc->writeback_rate_proportional = proportional; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 66 | dc->writeback_rate_derivative = derivative; |
| 67 | dc->writeback_rate_change = change; |
| 68 | dc->writeback_rate_target = target; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 69 | } |
| 70 | |
| 71 | static void update_writeback_rate(struct work_struct *work) |
| 72 | { |
| 73 | struct cached_dev *dc = container_of(to_delayed_work(work), |
| 74 | struct cached_dev, |
| 75 | writeback_rate_update); |
| 76 | |
| 77 | down_read(&dc->writeback_lock); |
| 78 | |
| 79 | if (atomic_read(&dc->has_dirty) && |
| 80 | dc->writeback_percent) |
| 81 | __update_writeback_rate(dc); |
| 82 | |
| 83 | up_read(&dc->writeback_lock); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 84 | |
| 85 | schedule_delayed_work(&dc->writeback_rate_update, |
| 86 | dc->writeback_rate_update_seconds * HZ); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 87 | } |
| 88 | |
| 89 | static unsigned writeback_delay(struct cached_dev *dc, unsigned sectors) |
| 90 | { |
Kent Overstreet | c4d951d | 2013-08-21 17:49:09 -0700 | [diff] [blame] | 91 | if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 92 | !dc->writeback_percent) |
| 93 | return 0; |
| 94 | |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 95 | return bch_next_delay(&dc->writeback_rate, sectors); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 96 | } |
| 97 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 98 | struct dirty_io { |
| 99 | struct closure cl; |
| 100 | struct cached_dev *dc; |
| 101 | struct bio bio; |
| 102 | }; |
Kent Overstreet | 72c2706 | 2013-06-05 06:24:39 -0700 | [diff] [blame] | 103 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 104 | static void dirty_init(struct keybuf_key *w) |
| 105 | { |
| 106 | struct dirty_io *io = w->private; |
| 107 | struct bio *bio = &io->bio; |
| 108 | |
| 109 | bio_init(bio); |
| 110 | if (!io->dc->writeback_percent) |
| 111 | bio_set_prio(bio, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0)); |
| 112 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 113 | bio->bi_iter.bi_size = KEY_SIZE(&w->key) << 9; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 114 | bio->bi_max_vecs = DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS); |
| 115 | bio->bi_private = w; |
| 116 | bio->bi_io_vec = bio->bi_inline_vecs; |
Kent Overstreet | 169ef1c | 2013-03-28 12:50:55 -0600 | [diff] [blame] | 117 | bch_bio_map(bio, NULL); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 118 | } |
| 119 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 120 | static void dirty_io_destructor(struct closure *cl) |
| 121 | { |
| 122 | struct dirty_io *io = container_of(cl, struct dirty_io, cl); |
| 123 | kfree(io); |
| 124 | } |
| 125 | |
| 126 | static void write_dirty_finish(struct closure *cl) |
| 127 | { |
| 128 | struct dirty_io *io = container_of(cl, struct dirty_io, cl); |
| 129 | struct keybuf_key *w = io->bio.bi_private; |
| 130 | struct cached_dev *dc = io->dc; |
Kent Overstreet | 8e51e41 | 2013-06-06 18:15:57 -0700 | [diff] [blame] | 131 | struct bio_vec *bv; |
| 132 | int i; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 133 | |
Kent Overstreet | 8e51e41 | 2013-06-06 18:15:57 -0700 | [diff] [blame] | 134 | bio_for_each_segment_all(bv, &io->bio, i) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 135 | __free_page(bv->bv_page); |
| 136 | |
| 137 | /* This is kind of a dumb way of signalling errors. */ |
| 138 | if (KEY_DIRTY(&w->key)) { |
Kent Overstreet | 6054c6d | 2013-07-24 18:06:22 -0700 | [diff] [blame] | 139 | int ret; |
Kent Overstreet | cc7b881 | 2013-07-24 18:07:22 -0700 | [diff] [blame] | 140 | unsigned i; |
| 141 | struct keylist keys; |
Kent Overstreet | 0b93207 | 2013-07-24 17:26:51 -0700 | [diff] [blame] | 142 | |
Kent Overstreet | 0b93207 | 2013-07-24 17:26:51 -0700 | [diff] [blame] | 143 | bch_keylist_init(&keys); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 144 | |
Kent Overstreet | 1b207d8 | 2013-09-10 18:52:54 -0700 | [diff] [blame] | 145 | bkey_copy(keys.top, &w->key); |
| 146 | SET_KEY_DIRTY(keys.top, false); |
| 147 | bch_keylist_push(&keys); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 148 | |
| 149 | for (i = 0; i < KEY_PTRS(&w->key); i++) |
| 150 | atomic_inc(&PTR_BUCKET(dc->disk.c, &w->key, i)->pin); |
| 151 | |
Kent Overstreet | cc7b881 | 2013-07-24 18:07:22 -0700 | [diff] [blame] | 152 | ret = bch_btree_insert(dc->disk.c, &keys, NULL, &w->key); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 153 | |
Kent Overstreet | 6054c6d | 2013-07-24 18:06:22 -0700 | [diff] [blame] | 154 | if (ret) |
Kent Overstreet | c37511b | 2013-04-26 15:39:55 -0700 | [diff] [blame] | 155 | trace_bcache_writeback_collision(&w->key); |
| 156 | |
Kent Overstreet | 6054c6d | 2013-07-24 18:06:22 -0700 | [diff] [blame] | 157 | atomic_long_inc(ret |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 158 | ? &dc->disk.c->writeback_keys_failed |
| 159 | : &dc->disk.c->writeback_keys_done); |
| 160 | } |
| 161 | |
| 162 | bch_keybuf_del(&dc->writeback_keys, w); |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 163 | up(&dc->in_flight); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 164 | |
| 165 | closure_return_with_destructor(cl, dirty_io_destructor); |
| 166 | } |
| 167 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 168 | static void dirty_endio(struct bio *bio) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 169 | { |
| 170 | struct keybuf_key *w = bio->bi_private; |
| 171 | struct dirty_io *io = w->private; |
| 172 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 173 | if (bio->bi_error) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 174 | SET_KEY_DIRTY(&w->key, false); |
| 175 | |
| 176 | closure_put(&io->cl); |
| 177 | } |
| 178 | |
| 179 | static void write_dirty(struct closure *cl) |
| 180 | { |
| 181 | struct dirty_io *io = container_of(cl, struct dirty_io, cl); |
| 182 | struct keybuf_key *w = io->bio.bi_private; |
| 183 | |
| 184 | dirty_init(w); |
Mike Christie | ad0d9e7 | 2016-06-05 14:32:05 -0500 | [diff] [blame] | 185 | bio_set_op_attrs(&io->bio, REQ_OP_WRITE, 0); |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 186 | io->bio.bi_iter.bi_sector = KEY_START(&w->key); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 187 | io->bio.bi_bdev = io->dc->bdev; |
| 188 | io->bio.bi_end_io = dirty_endio; |
| 189 | |
Kent Overstreet | 749b61d | 2013-11-23 23:11:25 -0800 | [diff] [blame] | 190 | closure_bio_submit(&io->bio, cl); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 191 | |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 192 | continue_at(cl, write_dirty_finish, system_wq); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 193 | } |
| 194 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 195 | static void read_dirty_endio(struct bio *bio) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 196 | { |
| 197 | struct keybuf_key *w = bio->bi_private; |
| 198 | struct dirty_io *io = w->private; |
| 199 | |
| 200 | bch_count_io_errors(PTR_CACHE(io->dc->disk.c, &w->key, 0), |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 201 | bio->bi_error, "reading dirty data from cache"); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 202 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 203 | dirty_endio(bio); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 204 | } |
| 205 | |
| 206 | static void read_dirty_submit(struct closure *cl) |
| 207 | { |
| 208 | struct dirty_io *io = container_of(cl, struct dirty_io, cl); |
| 209 | |
Kent Overstreet | 749b61d | 2013-11-23 23:11:25 -0800 | [diff] [blame] | 210 | closure_bio_submit(&io->bio, cl); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 211 | |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 212 | continue_at(cl, write_dirty, system_wq); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 213 | } |
| 214 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 215 | static void read_dirty(struct cached_dev *dc) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 216 | { |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 217 | unsigned delay = 0; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 218 | struct keybuf_key *w; |
| 219 | struct dirty_io *io; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 220 | struct closure cl; |
| 221 | |
| 222 | closure_init_stack(&cl); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 223 | |
| 224 | /* |
| 225 | * XXX: if we error, background writeback just spins. Should use some |
| 226 | * mempools. |
| 227 | */ |
| 228 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 229 | while (!kthread_should_stop()) { |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 230 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 231 | w = bch_keybuf_next(&dc->writeback_keys); |
| 232 | if (!w) |
| 233 | break; |
| 234 | |
| 235 | BUG_ON(ptr_stale(dc->disk.c, &w->key, 0)); |
| 236 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 237 | if (KEY_START(&w->key) != dc->last_read || |
| 238 | jiffies_to_msecs(delay) > 50) |
| 239 | while (!kthread_should_stop() && delay) |
Slava Pestov | 9e5c353 | 2014-05-01 13:48:57 -0700 | [diff] [blame] | 240 | delay = schedule_timeout_interruptible(delay); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 241 | |
| 242 | dc->last_read = KEY_OFFSET(&w->key); |
| 243 | |
| 244 | io = kzalloc(sizeof(struct dirty_io) + sizeof(struct bio_vec) |
| 245 | * DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS), |
| 246 | GFP_KERNEL); |
| 247 | if (!io) |
| 248 | goto err; |
| 249 | |
| 250 | w->private = io; |
| 251 | io->dc = dc; |
| 252 | |
| 253 | dirty_init(w); |
Mike Christie | ad0d9e7 | 2016-06-05 14:32:05 -0500 | [diff] [blame] | 254 | bio_set_op_attrs(&io->bio, REQ_OP_READ, 0); |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 255 | io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 256 | io->bio.bi_bdev = PTR_CACHE(dc->disk.c, |
| 257 | &w->key, 0)->bdev; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 258 | io->bio.bi_end_io = read_dirty_endio; |
| 259 | |
Kent Overstreet | 8e51e41 | 2013-06-06 18:15:57 -0700 | [diff] [blame] | 260 | if (bio_alloc_pages(&io->bio, GFP_KERNEL)) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 261 | goto err_free; |
| 262 | |
Kent Overstreet | c37511b | 2013-04-26 15:39:55 -0700 | [diff] [blame] | 263 | trace_bcache_writeback(&w->key); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 264 | |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 265 | down(&dc->in_flight); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 266 | closure_call(&io->cl, read_dirty_submit, NULL, &cl); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 267 | |
| 268 | delay = writeback_delay(dc, KEY_SIZE(&w->key)); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 269 | } |
| 270 | |
| 271 | if (0) { |
| 272 | err_free: |
| 273 | kfree(w->private); |
| 274 | err: |
| 275 | bch_keybuf_del(&dc->writeback_keys, w); |
| 276 | } |
| 277 | |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 278 | /* |
| 279 | * Wait for outstanding writeback IOs to finish (and keybuf slots to be |
| 280 | * freed) before refilling again |
| 281 | */ |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 282 | closure_sync(&cl); |
| 283 | } |
| 284 | |
| 285 | /* Scan for dirty data */ |
| 286 | |
| 287 | void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode, |
| 288 | uint64_t offset, int nr_sectors) |
| 289 | { |
| 290 | struct bcache_device *d = c->devices[inode]; |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 291 | unsigned stripe_offset, stripe, sectors_dirty; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 292 | |
| 293 | if (!d) |
| 294 | return; |
| 295 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 296 | stripe = offset_to_stripe(d, offset); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 297 | stripe_offset = offset & (d->stripe_size - 1); |
| 298 | |
| 299 | while (nr_sectors) { |
| 300 | int s = min_t(unsigned, abs(nr_sectors), |
| 301 | d->stripe_size - stripe_offset); |
| 302 | |
| 303 | if (nr_sectors < 0) |
| 304 | s = -s; |
| 305 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 306 | if (stripe >= d->nr_stripes) |
| 307 | return; |
| 308 | |
| 309 | sectors_dirty = atomic_add_return(s, |
| 310 | d->stripe_sectors_dirty + stripe); |
| 311 | if (sectors_dirty == d->stripe_size) |
| 312 | set_bit(stripe, d->full_dirty_stripes); |
| 313 | else |
| 314 | clear_bit(stripe, d->full_dirty_stripes); |
| 315 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 316 | nr_sectors -= s; |
| 317 | stripe_offset = 0; |
| 318 | stripe++; |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | static bool dirty_pred(struct keybuf *buf, struct bkey *k) |
| 323 | { |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 324 | struct cached_dev *dc = container_of(buf, struct cached_dev, writeback_keys); |
| 325 | |
| 326 | BUG_ON(KEY_INODE(k) != dc->disk.id); |
| 327 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 328 | return KEY_DIRTY(k); |
| 329 | } |
| 330 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 331 | static void refill_full_stripes(struct cached_dev *dc) |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 332 | { |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 333 | struct keybuf *buf = &dc->writeback_keys; |
| 334 | unsigned start_stripe, stripe, next_stripe; |
| 335 | bool wrapped = false; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 336 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 337 | stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned)); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 338 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 339 | if (stripe >= dc->disk.nr_stripes) |
| 340 | stripe = 0; |
| 341 | |
| 342 | start_stripe = stripe; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 343 | |
| 344 | while (1) { |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 345 | stripe = find_next_bit(dc->disk.full_dirty_stripes, |
| 346 | dc->disk.nr_stripes, stripe); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 347 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 348 | if (stripe == dc->disk.nr_stripes) |
| 349 | goto next; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 350 | |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 351 | next_stripe = find_next_zero_bit(dc->disk.full_dirty_stripes, |
| 352 | dc->disk.nr_stripes, stripe); |
| 353 | |
| 354 | buf->last_scanned = KEY(dc->disk.id, |
| 355 | stripe * dc->disk.stripe_size, 0); |
| 356 | |
| 357 | bch_refill_keybuf(dc->disk.c, buf, |
| 358 | &KEY(dc->disk.id, |
| 359 | next_stripe * dc->disk.stripe_size, 0), |
| 360 | dirty_pred); |
| 361 | |
| 362 | if (array_freelist_empty(&buf->freelist)) |
| 363 | return; |
| 364 | |
| 365 | stripe = next_stripe; |
| 366 | next: |
| 367 | if (wrapped && stripe > start_stripe) |
| 368 | return; |
| 369 | |
| 370 | if (stripe == dc->disk.nr_stripes) { |
| 371 | stripe = 0; |
| 372 | wrapped = true; |
| 373 | } |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 374 | } |
| 375 | } |
| 376 | |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 377 | /* |
| 378 | * Returns true if we scanned the entire disk |
| 379 | */ |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 380 | static bool refill_dirty(struct cached_dev *dc) |
| 381 | { |
| 382 | struct keybuf *buf = &dc->writeback_keys; |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 383 | struct bkey start = KEY(dc->disk.id, 0, 0); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 384 | struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0); |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 385 | struct bkey start_pos; |
| 386 | |
| 387 | /* |
| 388 | * make sure keybuf pos is inside the range for this disk - at bringup |
| 389 | * we might not be attached yet so this disk's inode nr isn't |
| 390 | * initialized then |
| 391 | */ |
| 392 | if (bkey_cmp(&buf->last_scanned, &start) < 0 || |
| 393 | bkey_cmp(&buf->last_scanned, &end) > 0) |
| 394 | buf->last_scanned = start; |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 395 | |
| 396 | if (dc->partial_stripes_expensive) { |
| 397 | refill_full_stripes(dc); |
| 398 | if (array_freelist_empty(&buf->freelist)) |
| 399 | return false; |
| 400 | } |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 401 | |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 402 | start_pos = buf->last_scanned; |
Kent Overstreet | 48a915a | 2013-10-31 15:43:22 -0700 | [diff] [blame] | 403 | bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 404 | |
Kent Overstreet | 627ccd2 | 2015-11-29 18:47:01 -0800 | [diff] [blame] | 405 | if (bkey_cmp(&buf->last_scanned, &end) < 0) |
| 406 | return false; |
| 407 | |
| 408 | /* |
| 409 | * If we get to the end start scanning again from the beginning, and |
| 410 | * only scan up to where we initially started scanning from: |
| 411 | */ |
| 412 | buf->last_scanned = start; |
| 413 | bch_refill_keybuf(dc->disk.c, buf, &start_pos, dirty_pred); |
| 414 | |
| 415 | return bkey_cmp(&buf->last_scanned, &start_pos) >= 0; |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 416 | } |
| 417 | |
| 418 | static int bch_writeback_thread(void *arg) |
| 419 | { |
| 420 | struct cached_dev *dc = arg; |
| 421 | bool searched_full_index; |
| 422 | |
| 423 | while (!kthread_should_stop()) { |
| 424 | down_write(&dc->writeback_lock); |
| 425 | if (!atomic_read(&dc->has_dirty) || |
Kent Overstreet | c4d951d | 2013-08-21 17:49:09 -0700 | [diff] [blame] | 426 | (!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) && |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 427 | !dc->writeback_running)) { |
| 428 | up_write(&dc->writeback_lock); |
| 429 | set_current_state(TASK_INTERRUPTIBLE); |
| 430 | |
| 431 | if (kthread_should_stop()) |
| 432 | return 0; |
| 433 | |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 434 | schedule(); |
| 435 | continue; |
| 436 | } |
| 437 | |
| 438 | searched_full_index = refill_dirty(dc); |
| 439 | |
| 440 | if (searched_full_index && |
| 441 | RB_EMPTY_ROOT(&dc->writeback_keys.keys)) { |
| 442 | atomic_set(&dc->has_dirty, 0); |
| 443 | cached_dev_put(dc); |
| 444 | SET_BDEV_STATE(&dc->sb, BDEV_STATE_CLEAN); |
| 445 | bch_write_bdev_super(dc, NULL); |
| 446 | } |
| 447 | |
| 448 | up_write(&dc->writeback_lock); |
| 449 | |
| 450 | bch_ratelimit_reset(&dc->writeback_rate); |
| 451 | read_dirty(dc); |
| 452 | |
| 453 | if (searched_full_index) { |
| 454 | unsigned delay = dc->writeback_delay * HZ; |
| 455 | |
| 456 | while (delay && |
| 457 | !kthread_should_stop() && |
Kent Overstreet | c4d951d | 2013-08-21 17:49:09 -0700 | [diff] [blame] | 458 | !test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) |
Slava Pestov | 9e5c353 | 2014-05-01 13:48:57 -0700 | [diff] [blame] | 459 | delay = schedule_timeout_interruptible(delay); |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 460 | } |
| 461 | } |
| 462 | |
| 463 | return 0; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 464 | } |
| 465 | |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 466 | /* Init */ |
| 467 | |
Kent Overstreet | c18536a | 2013-07-24 17:44:17 -0700 | [diff] [blame] | 468 | struct sectors_dirty_init { |
| 469 | struct btree_op op; |
| 470 | unsigned inode; |
| 471 | }; |
| 472 | |
| 473 | static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b, |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 474 | struct bkey *k) |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 475 | { |
Kent Overstreet | c18536a | 2013-07-24 17:44:17 -0700 | [diff] [blame] | 476 | struct sectors_dirty_init *op = container_of(_op, |
| 477 | struct sectors_dirty_init, op); |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 478 | if (KEY_INODE(k) > op->inode) |
| 479 | return MAP_DONE; |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 480 | |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 481 | if (KEY_DIRTY(k)) |
| 482 | bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k), |
| 483 | KEY_START(k), KEY_SIZE(k)); |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 484 | |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 485 | return MAP_CONTINUE; |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 486 | } |
| 487 | |
| 488 | void bch_sectors_dirty_init(struct cached_dev *dc) |
| 489 | { |
Kent Overstreet | c18536a | 2013-07-24 17:44:17 -0700 | [diff] [blame] | 490 | struct sectors_dirty_init op; |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 491 | |
Kent Overstreet | b54d693 | 2013-07-24 18:04:18 -0700 | [diff] [blame] | 492 | bch_btree_op_init(&op.op, -1); |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 493 | op.inode = dc->disk.id; |
| 494 | |
Kent Overstreet | c18536a | 2013-07-24 17:44:17 -0700 | [diff] [blame] | 495 | bch_btree_map_keys(&op.op, dc->disk.c, &KEY(op.inode, 0, 0), |
Kent Overstreet | 48dad8b | 2013-09-10 18:48:51 -0700 | [diff] [blame] | 496 | sectors_dirty_init_fn, 0); |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 497 | |
| 498 | dc->disk.sectors_dirty_last = bcache_dev_sectors_dirty(&dc->disk); |
Kent Overstreet | 444fc0b | 2013-05-11 17:07:26 -0700 | [diff] [blame] | 499 | } |
| 500 | |
Slava Pestov | 9e5c353 | 2014-05-01 13:48:57 -0700 | [diff] [blame] | 501 | void bch_cached_dev_writeback_init(struct cached_dev *dc) |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 502 | { |
Kent Overstreet | c2a4f31 | 2013-09-23 23:17:31 -0700 | [diff] [blame] | 503 | sema_init(&dc->in_flight, 64); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 504 | init_rwsem(&dc->writeback_lock); |
Kent Overstreet | 72c2706 | 2013-06-05 06:24:39 -0700 | [diff] [blame] | 505 | bch_keybuf_init(&dc->writeback_keys); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 506 | |
| 507 | dc->writeback_metadata = true; |
| 508 | dc->writeback_running = true; |
| 509 | dc->writeback_percent = 10; |
| 510 | dc->writeback_delay = 30; |
| 511 | dc->writeback_rate.rate = 1024; |
| 512 | |
Kent Overstreet | 16749c2 | 2013-11-11 13:58:34 -0800 | [diff] [blame] | 513 | dc->writeback_rate_update_seconds = 5; |
| 514 | dc->writeback_rate_d_term = 30; |
| 515 | dc->writeback_rate_p_term_inverse = 6000; |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 516 | |
Slava Pestov | 9e5c353 | 2014-05-01 13:48:57 -0700 | [diff] [blame] | 517 | INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate); |
| 518 | } |
| 519 | |
| 520 | int bch_cached_dev_writeback_start(struct cached_dev *dc) |
| 521 | { |
Kent Overstreet | 5e6926d | 2013-07-24 17:50:06 -0700 | [diff] [blame] | 522 | dc->writeback_thread = kthread_create(bch_writeback_thread, dc, |
| 523 | "bcache_writeback"); |
| 524 | if (IS_ERR(dc->writeback_thread)) |
| 525 | return PTR_ERR(dc->writeback_thread); |
| 526 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 527 | schedule_delayed_work(&dc->writeback_rate_update, |
| 528 | dc->writeback_rate_update_seconds * HZ); |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 529 | |
Slava Pestov | 9e5c353 | 2014-05-01 13:48:57 -0700 | [diff] [blame] | 530 | bch_writeback_queue(dc); |
| 531 | |
Kent Overstreet | cafe563 | 2013-03-23 16:11:31 -0700 | [diff] [blame] | 532 | return 0; |
| 533 | } |