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cafe5635 KO |
1 | /* |
2 | * Copyright (C) 2010 Kent Overstreet <kent.overstreet@gmail.com> | |
3 | * | |
4 | * Uses a block device as cache for other block devices; optimized for SSDs. | |
5 | * All allocation is done in buckets, which should match the erase block size | |
6 | * of the device. | |
7 | * | |
8 | * Buckets containing cached data are kept on a heap sorted by priority; | |
9 | * bucket priority is increased on cache hit, and periodically all the buckets | |
10 | * on the heap have their priority scaled down. This currently is just used as | |
11 | * an LRU but in the future should allow for more intelligent heuristics. | |
12 | * | |
13 | * Buckets have an 8 bit counter; freeing is accomplished by incrementing the | |
14 | * counter. Garbage collection is used to remove stale pointers. | |
15 | * | |
16 | * Indexing is done via a btree; nodes are not necessarily fully sorted, rather | |
17 | * as keys are inserted we only sort the pages that have not yet been written. | |
18 | * When garbage collection is run, we resort the entire node. | |
19 | * | |
20 | * All configuration is done via sysfs; see Documentation/bcache.txt. | |
21 | */ | |
22 | ||
23 | #include "bcache.h" | |
24 | #include "btree.h" | |
25 | #include "debug.h" | |
65d45231 | 26 | #include "extents.h" |
cafe5635 KO |
27 | |
28 | #include <linux/slab.h> | |
29 | #include <linux/bitops.h> | |
30 | #include <linux/hash.h> | |
72a44517 | 31 | #include <linux/kthread.h> |
cd953ed0 | 32 | #include <linux/prefetch.h> |
cafe5635 KO |
33 | #include <linux/random.h> |
34 | #include <linux/rcupdate.h> | |
35 | #include <trace/events/bcache.h> | |
36 | ||
37 | /* | |
38 | * Todo: | |
39 | * register_bcache: Return errors out to userspace correctly | |
40 | * | |
41 | * Writeback: don't undirty key until after a cache flush | |
42 | * | |
43 | * Create an iterator for key pointers | |
44 | * | |
45 | * On btree write error, mark bucket such that it won't be freed from the cache | |
46 | * | |
47 | * Journalling: | |
48 | * Check for bad keys in replay | |
49 | * Propagate barriers | |
50 | * Refcount journal entries in journal_replay | |
51 | * | |
52 | * Garbage collection: | |
53 | * Finish incremental gc | |
54 | * Gc should free old UUIDs, data for invalid UUIDs | |
55 | * | |
56 | * Provide a way to list backing device UUIDs we have data cached for, and | |
57 | * probably how long it's been since we've seen them, and a way to invalidate | |
58 | * dirty data for devices that will never be attached again | |
59 | * | |
60 | * Keep 1 min/5 min/15 min statistics of how busy a block device has been, so | |
61 | * that based on that and how much dirty data we have we can keep writeback | |
62 | * from being starved | |
63 | * | |
64 | * Add a tracepoint or somesuch to watch for writeback starvation | |
65 | * | |
66 | * When btree depth > 1 and splitting an interior node, we have to make sure | |
67 | * alloc_bucket() cannot fail. This should be true but is not completely | |
68 | * obvious. | |
69 | * | |
cafe5635 KO |
70 | * Plugging? |
71 | * | |
72 | * If data write is less than hard sector size of ssd, round up offset in open | |
73 | * bucket to the next whole sector | |
74 | * | |
cafe5635 KO |
75 | * Superblock needs to be fleshed out for multiple cache devices |
76 | * | |
77 | * Add a sysfs tunable for the number of writeback IOs in flight | |
78 | * | |
79 | * Add a sysfs tunable for the number of open data buckets | |
80 | * | |
81 | * IO tracking: Can we track when one process is doing io on behalf of another? | |
82 | * IO tracking: Don't use just an average, weigh more recent stuff higher | |
83 | * | |
84 | * Test module load/unload | |
85 | */ | |
86 | ||
cafe5635 KO |
87 | #define MAX_NEED_GC 64 |
88 | #define MAX_SAVE_PRIO 72 | |
89 | ||
90 | #define PTR_DIRTY_BIT (((uint64_t) 1 << 36)) | |
91 | ||
92 | #define PTR_HASH(c, k) \ | |
93 | (((k)->ptr[0] >> c->bucket_bits) | PTR_GEN(k, 0)) | |
94 | ||
df8e8970 KO |
95 | #define insert_lock(s, b) ((b)->level <= (s)->lock) |
96 | ||
97 | /* | |
98 | * These macros are for recursing down the btree - they handle the details of | |
99 | * locking and looking up nodes in the cache for you. They're best treated as | |
100 | * mere syntax when reading code that uses them. | |
101 | * | |
102 | * op->lock determines whether we take a read or a write lock at a given depth. | |
103 | * If you've got a read lock and find that you need a write lock (i.e. you're | |
104 | * going to have to split), set op->lock and return -EINTR; btree_root() will | |
105 | * call you again and you'll have the correct lock. | |
106 | */ | |
107 | ||
108 | /** | |
109 | * btree - recurse down the btree on a specified key | |
110 | * @fn: function to call, which will be passed the child node | |
111 | * @key: key to recurse on | |
112 | * @b: parent btree node | |
113 | * @op: pointer to struct btree_op | |
114 | */ | |
115 | #define btree(fn, key, b, op, ...) \ | |
116 | ({ \ | |
117 | int _r, l = (b)->level - 1; \ | |
118 | bool _w = l <= (op)->lock; \ | |
2452cc89 SP |
119 | struct btree *_child = bch_btree_node_get((b)->c, op, key, l, \ |
120 | _w, b); \ | |
df8e8970 | 121 | if (!IS_ERR(_child)) { \ |
df8e8970 KO |
122 | _r = bch_btree_ ## fn(_child, op, ##__VA_ARGS__); \ |
123 | rw_unlock(_w, _child); \ | |
124 | } else \ | |
125 | _r = PTR_ERR(_child); \ | |
126 | _r; \ | |
127 | }) | |
128 | ||
129 | /** | |
130 | * btree_root - call a function on the root of the btree | |
131 | * @fn: function to call, which will be passed the child node | |
132 | * @c: cache set | |
133 | * @op: pointer to struct btree_op | |
134 | */ | |
135 | #define btree_root(fn, c, op, ...) \ | |
136 | ({ \ | |
137 | int _r = -EINTR; \ | |
138 | do { \ | |
139 | struct btree *_b = (c)->root; \ | |
140 | bool _w = insert_lock(op, _b); \ | |
141 | rw_lock(_w, _b, _b->level); \ | |
142 | if (_b == (c)->root && \ | |
143 | _w == insert_lock(op, _b)) { \ | |
df8e8970 KO |
144 | _r = bch_btree_ ## fn(_b, op, ##__VA_ARGS__); \ |
145 | } \ | |
146 | rw_unlock(_w, _b); \ | |
0a63b66d | 147 | bch_cannibalize_unlock(c); \ |
78365411 KO |
148 | if (_r == -EINTR) \ |
149 | schedule(); \ | |
df8e8970 KO |
150 | } while (_r == -EINTR); \ |
151 | \ | |
0a63b66d | 152 | finish_wait(&(c)->btree_cache_wait, &(op)->wait); \ |
df8e8970 KO |
153 | _r; \ |
154 | }) | |
155 | ||
a85e968e KO |
156 | static inline struct bset *write_block(struct btree *b) |
157 | { | |
158 | return ((void *) btree_bset_first(b)) + b->written * block_bytes(b->c); | |
159 | } | |
160 | ||
2a285686 KO |
161 | static void bch_btree_init_next(struct btree *b) |
162 | { | |
163 | /* If not a leaf node, always sort */ | |
164 | if (b->level && b->keys.nsets) | |
165 | bch_btree_sort(&b->keys, &b->c->sort); | |
166 | else | |
167 | bch_btree_sort_lazy(&b->keys, &b->c->sort); | |
168 | ||
169 | if (b->written < btree_blocks(b)) | |
170 | bch_bset_init_next(&b->keys, write_block(b), | |
171 | bset_magic(&b->c->sb)); | |
172 | ||
173 | } | |
174 | ||
cafe5635 KO |
175 | /* Btree key manipulation */ |
176 | ||
3a3b6a4e | 177 | void bkey_put(struct cache_set *c, struct bkey *k) |
e7c590eb KO |
178 | { |
179 | unsigned i; | |
180 | ||
181 | for (i = 0; i < KEY_PTRS(k); i++) | |
182 | if (ptr_available(c, k, i)) | |
183 | atomic_dec_bug(&PTR_BUCKET(c, k, i)->pin); | |
184 | } | |
185 | ||
cafe5635 KO |
186 | /* Btree IO */ |
187 | ||
188 | static uint64_t btree_csum_set(struct btree *b, struct bset *i) | |
189 | { | |
190 | uint64_t crc = b->key.ptr[0]; | |
fafff81c | 191 | void *data = (void *) i + 8, *end = bset_bkey_last(i); |
cafe5635 | 192 | |
169ef1cf | 193 | crc = bch_crc64_update(crc, data, end - data); |
c19ed23a | 194 | return crc ^ 0xffffffffffffffffULL; |
cafe5635 KO |
195 | } |
196 | ||
78b77bf8 | 197 | void bch_btree_node_read_done(struct btree *b) |
cafe5635 | 198 | { |
cafe5635 | 199 | const char *err = "bad btree header"; |
ee811287 | 200 | struct bset *i = btree_bset_first(b); |
57943511 | 201 | struct btree_iter *iter; |
cafe5635 | 202 | |
bcf090e0 | 203 | iter = mempool_alloc(b->c->fill_iter, GFP_NOIO); |
57943511 | 204 | iter->size = b->c->sb.bucket_size / b->c->sb.block_size; |
cafe5635 KO |
205 | iter->used = 0; |
206 | ||
280481d0 | 207 | #ifdef CONFIG_BCACHE_DEBUG |
c052dd9a | 208 | iter->b = &b->keys; |
280481d0 KO |
209 | #endif |
210 | ||
57943511 | 211 | if (!i->seq) |
cafe5635 KO |
212 | goto err; |
213 | ||
214 | for (; | |
a85e968e | 215 | b->written < btree_blocks(b) && i->seq == b->keys.set[0].data->seq; |
cafe5635 KO |
216 | i = write_block(b)) { |
217 | err = "unsupported bset version"; | |
218 | if (i->version > BCACHE_BSET_VERSION) | |
219 | goto err; | |
220 | ||
221 | err = "bad btree header"; | |
ee811287 KO |
222 | if (b->written + set_blocks(i, block_bytes(b->c)) > |
223 | btree_blocks(b)) | |
cafe5635 KO |
224 | goto err; |
225 | ||
226 | err = "bad magic"; | |
81ab4190 | 227 | if (i->magic != bset_magic(&b->c->sb)) |
cafe5635 KO |
228 | goto err; |
229 | ||
230 | err = "bad checksum"; | |
231 | switch (i->version) { | |
232 | case 0: | |
233 | if (i->csum != csum_set(i)) | |
234 | goto err; | |
235 | break; | |
236 | case BCACHE_BSET_VERSION: | |
237 | if (i->csum != btree_csum_set(b, i)) | |
238 | goto err; | |
239 | break; | |
240 | } | |
241 | ||
242 | err = "empty set"; | |
a85e968e | 243 | if (i != b->keys.set[0].data && !i->keys) |
cafe5635 KO |
244 | goto err; |
245 | ||
fafff81c | 246 | bch_btree_iter_push(iter, i->start, bset_bkey_last(i)); |
cafe5635 | 247 | |
ee811287 | 248 | b->written += set_blocks(i, block_bytes(b->c)); |
cafe5635 KO |
249 | } |
250 | ||
251 | err = "corrupted btree"; | |
252 | for (i = write_block(b); | |
a85e968e | 253 | bset_sector_offset(&b->keys, i) < KEY_SIZE(&b->key); |
cafe5635 | 254 | i = ((void *) i) + block_bytes(b->c)) |
a85e968e | 255 | if (i->seq == b->keys.set[0].data->seq) |
cafe5635 KO |
256 | goto err; |
257 | ||
a85e968e | 258 | bch_btree_sort_and_fix_extents(&b->keys, iter, &b->c->sort); |
cafe5635 | 259 | |
a85e968e | 260 | i = b->keys.set[0].data; |
cafe5635 | 261 | err = "short btree key"; |
a85e968e KO |
262 | if (b->keys.set[0].size && |
263 | bkey_cmp(&b->key, &b->keys.set[0].end) < 0) | |
cafe5635 KO |
264 | goto err; |
265 | ||
266 | if (b->written < btree_blocks(b)) | |
a85e968e KO |
267 | bch_bset_init_next(&b->keys, write_block(b), |
268 | bset_magic(&b->c->sb)); | |
cafe5635 | 269 | out: |
57943511 KO |
270 | mempool_free(iter, b->c->fill_iter); |
271 | return; | |
cafe5635 KO |
272 | err: |
273 | set_btree_node_io_error(b); | |
88b9f8c4 | 274 | bch_cache_set_error(b->c, "%s at bucket %zu, block %u, %u keys", |
cafe5635 | 275 | err, PTR_BUCKET_NR(b->c, &b->key, 0), |
88b9f8c4 | 276 | bset_block_offset(b, i), i->keys); |
cafe5635 KO |
277 | goto out; |
278 | } | |
279 | ||
4246a0b6 | 280 | static void btree_node_read_endio(struct bio *bio) |
cafe5635 | 281 | { |
57943511 KO |
282 | struct closure *cl = bio->bi_private; |
283 | closure_put(cl); | |
284 | } | |
cafe5635 | 285 | |
78b77bf8 | 286 | static void bch_btree_node_read(struct btree *b) |
57943511 KO |
287 | { |
288 | uint64_t start_time = local_clock(); | |
289 | struct closure cl; | |
290 | struct bio *bio; | |
cafe5635 | 291 | |
c37511b8 KO |
292 | trace_bcache_btree_read(b); |
293 | ||
57943511 | 294 | closure_init_stack(&cl); |
cafe5635 | 295 | |
57943511 | 296 | bio = bch_bbio_alloc(b->c); |
4f024f37 | 297 | bio->bi_iter.bi_size = KEY_SIZE(&b->key) << 9; |
57943511 KO |
298 | bio->bi_end_io = btree_node_read_endio; |
299 | bio->bi_private = &cl; | |
ad0d9e76 | 300 | bio_set_op_attrs(bio, REQ_OP_READ, REQ_META|READ_SYNC); |
cafe5635 | 301 | |
a85e968e | 302 | bch_bio_map(bio, b->keys.set[0].data); |
cafe5635 | 303 | |
57943511 KO |
304 | bch_submit_bbio(bio, b->c, &b->key, 0); |
305 | closure_sync(&cl); | |
cafe5635 | 306 | |
4246a0b6 | 307 | if (bio->bi_error) |
57943511 KO |
308 | set_btree_node_io_error(b); |
309 | ||
310 | bch_bbio_free(bio, b->c); | |
311 | ||
312 | if (btree_node_io_error(b)) | |
313 | goto err; | |
314 | ||
315 | bch_btree_node_read_done(b); | |
57943511 | 316 | bch_time_stats_update(&b->c->btree_read_time, start_time); |
57943511 KO |
317 | |
318 | return; | |
319 | err: | |
61cbd250 | 320 | bch_cache_set_error(b->c, "io error reading bucket %zu", |
57943511 | 321 | PTR_BUCKET_NR(b->c, &b->key, 0)); |
cafe5635 KO |
322 | } |
323 | ||
324 | static void btree_complete_write(struct btree *b, struct btree_write *w) | |
325 | { | |
326 | if (w->prio_blocked && | |
327 | !atomic_sub_return(w->prio_blocked, &b->c->prio_blocked)) | |
119ba0f8 | 328 | wake_up_allocators(b->c); |
cafe5635 KO |
329 | |
330 | if (w->journal) { | |
331 | atomic_dec_bug(w->journal); | |
332 | __closure_wake_up(&b->c->journal.wait); | |
333 | } | |
334 | ||
cafe5635 KO |
335 | w->prio_blocked = 0; |
336 | w->journal = NULL; | |
cafe5635 KO |
337 | } |
338 | ||
cb7a583e KO |
339 | static void btree_node_write_unlock(struct closure *cl) |
340 | { | |
341 | struct btree *b = container_of(cl, struct btree, io); | |
342 | ||
343 | up(&b->io_mutex); | |
344 | } | |
345 | ||
57943511 | 346 | static void __btree_node_write_done(struct closure *cl) |
cafe5635 | 347 | { |
cb7a583e | 348 | struct btree *b = container_of(cl, struct btree, io); |
cafe5635 KO |
349 | struct btree_write *w = btree_prev_write(b); |
350 | ||
351 | bch_bbio_free(b->bio, b->c); | |
352 | b->bio = NULL; | |
353 | btree_complete_write(b, w); | |
354 | ||
355 | if (btree_node_dirty(b)) | |
56b30770 | 356 | schedule_delayed_work(&b->work, 30 * HZ); |
cafe5635 | 357 | |
cb7a583e | 358 | closure_return_with_destructor(cl, btree_node_write_unlock); |
cafe5635 KO |
359 | } |
360 | ||
57943511 | 361 | static void btree_node_write_done(struct closure *cl) |
cafe5635 | 362 | { |
cb7a583e | 363 | struct btree *b = container_of(cl, struct btree, io); |
cafe5635 KO |
364 | struct bio_vec *bv; |
365 | int n; | |
366 | ||
7988613b | 367 | bio_for_each_segment_all(bv, b->bio, n) |
cafe5635 KO |
368 | __free_page(bv->bv_page); |
369 | ||
57943511 | 370 | __btree_node_write_done(cl); |
cafe5635 KO |
371 | } |
372 | ||
4246a0b6 | 373 | static void btree_node_write_endio(struct bio *bio) |
57943511 KO |
374 | { |
375 | struct closure *cl = bio->bi_private; | |
cb7a583e | 376 | struct btree *b = container_of(cl, struct btree, io); |
57943511 | 377 | |
4246a0b6 | 378 | if (bio->bi_error) |
57943511 KO |
379 | set_btree_node_io_error(b); |
380 | ||
4246a0b6 | 381 | bch_bbio_count_io_errors(b->c, bio, bio->bi_error, "writing btree"); |
57943511 KO |
382 | closure_put(cl); |
383 | } | |
384 | ||
385 | static void do_btree_node_write(struct btree *b) | |
cafe5635 | 386 | { |
cb7a583e | 387 | struct closure *cl = &b->io; |
ee811287 | 388 | struct bset *i = btree_bset_last(b); |
cafe5635 KO |
389 | BKEY_PADDED(key) k; |
390 | ||
391 | i->version = BCACHE_BSET_VERSION; | |
392 | i->csum = btree_csum_set(b, i); | |
393 | ||
57943511 KO |
394 | BUG_ON(b->bio); |
395 | b->bio = bch_bbio_alloc(b->c); | |
396 | ||
397 | b->bio->bi_end_io = btree_node_write_endio; | |
faadf0c9 | 398 | b->bio->bi_private = cl; |
ee811287 | 399 | b->bio->bi_iter.bi_size = roundup(set_bytes(i), block_bytes(b->c)); |
ad0d9e76 | 400 | bio_set_op_attrs(b->bio, REQ_OP_WRITE, REQ_META|WRITE_SYNC|REQ_FUA); |
169ef1cf | 401 | bch_bio_map(b->bio, i); |
cafe5635 | 402 | |
e49c7c37 KO |
403 | /* |
404 | * If we're appending to a leaf node, we don't technically need FUA - | |
405 | * this write just needs to be persisted before the next journal write, | |
406 | * which will be marked FLUSH|FUA. | |
407 | * | |
408 | * Similarly if we're writing a new btree root - the pointer is going to | |
409 | * be in the next journal entry. | |
410 | * | |
411 | * But if we're writing a new btree node (that isn't a root) or | |
412 | * appending to a non leaf btree node, we need either FUA or a flush | |
413 | * when we write the parent with the new pointer. FUA is cheaper than a | |
414 | * flush, and writes appending to leaf nodes aren't blocking anything so | |
415 | * just make all btree node writes FUA to keep things sane. | |
416 | */ | |
417 | ||
cafe5635 | 418 | bkey_copy(&k.key, &b->key); |
ee811287 | 419 | SET_PTR_OFFSET(&k.key, 0, PTR_OFFSET(&k.key, 0) + |
a85e968e | 420 | bset_sector_offset(&b->keys, i)); |
cafe5635 | 421 | |
501d52a9 | 422 | if (!bio_alloc_pages(b->bio, __GFP_NOWARN|GFP_NOWAIT)) { |
cafe5635 KO |
423 | int j; |
424 | struct bio_vec *bv; | |
425 | void *base = (void *) ((unsigned long) i & ~(PAGE_SIZE - 1)); | |
426 | ||
7988613b | 427 | bio_for_each_segment_all(bv, b->bio, j) |
cafe5635 KO |
428 | memcpy(page_address(bv->bv_page), |
429 | base + j * PAGE_SIZE, PAGE_SIZE); | |
430 | ||
cafe5635 KO |
431 | bch_submit_bbio(b->bio, b->c, &k.key, 0); |
432 | ||
57943511 | 433 | continue_at(cl, btree_node_write_done, NULL); |
cafe5635 KO |
434 | } else { |
435 | b->bio->bi_vcnt = 0; | |
169ef1cf | 436 | bch_bio_map(b->bio, i); |
cafe5635 | 437 | |
cafe5635 KO |
438 | bch_submit_bbio(b->bio, b->c, &k.key, 0); |
439 | ||
440 | closure_sync(cl); | |
cb7a583e | 441 | continue_at_nobarrier(cl, __btree_node_write_done, NULL); |
cafe5635 KO |
442 | } |
443 | } | |
444 | ||
2a285686 | 445 | void __bch_btree_node_write(struct btree *b, struct closure *parent) |
cafe5635 | 446 | { |
ee811287 | 447 | struct bset *i = btree_bset_last(b); |
cafe5635 | 448 | |
2a285686 KO |
449 | lockdep_assert_held(&b->write_lock); |
450 | ||
c37511b8 KO |
451 | trace_bcache_btree_write(b); |
452 | ||
cafe5635 | 453 | BUG_ON(current->bio_list); |
57943511 KO |
454 | BUG_ON(b->written >= btree_blocks(b)); |
455 | BUG_ON(b->written && !i->keys); | |
ee811287 | 456 | BUG_ON(btree_bset_first(b)->seq != i->seq); |
dc9d98d6 | 457 | bch_check_keys(&b->keys, "writing"); |
cafe5635 | 458 | |
cafe5635 KO |
459 | cancel_delayed_work(&b->work); |
460 | ||
57943511 | 461 | /* If caller isn't waiting for write, parent refcount is cache set */ |
cb7a583e KO |
462 | down(&b->io_mutex); |
463 | closure_init(&b->io, parent ?: &b->c->cl); | |
57943511 | 464 | |
cafe5635 KO |
465 | clear_bit(BTREE_NODE_dirty, &b->flags); |
466 | change_bit(BTREE_NODE_write_idx, &b->flags); | |
467 | ||
57943511 | 468 | do_btree_node_write(b); |
cafe5635 | 469 | |
ee811287 | 470 | atomic_long_add(set_blocks(i, block_bytes(b->c)) * b->c->sb.block_size, |
cafe5635 KO |
471 | &PTR_CACHE(b->c, &b->key, 0)->btree_sectors_written); |
472 | ||
a85e968e | 473 | b->written += set_blocks(i, block_bytes(b->c)); |
2a285686 | 474 | } |
a85e968e | 475 | |
2a285686 KO |
476 | void bch_btree_node_write(struct btree *b, struct closure *parent) |
477 | { | |
478 | unsigned nsets = b->keys.nsets; | |
479 | ||
480 | lockdep_assert_held(&b->lock); | |
481 | ||
482 | __bch_btree_node_write(b, parent); | |
cafe5635 | 483 | |
78b77bf8 KO |
484 | /* |
485 | * do verify if there was more than one set initially (i.e. we did a | |
486 | * sort) and we sorted down to a single set: | |
487 | */ | |
2a285686 | 488 | if (nsets && !b->keys.nsets) |
78b77bf8 KO |
489 | bch_btree_verify(b); |
490 | ||
2a285686 | 491 | bch_btree_init_next(b); |
cafe5635 KO |
492 | } |
493 | ||
f269af5a KO |
494 | static void bch_btree_node_write_sync(struct btree *b) |
495 | { | |
496 | struct closure cl; | |
497 | ||
498 | closure_init_stack(&cl); | |
2a285686 KO |
499 | |
500 | mutex_lock(&b->write_lock); | |
f269af5a | 501 | bch_btree_node_write(b, &cl); |
2a285686 KO |
502 | mutex_unlock(&b->write_lock); |
503 | ||
f269af5a KO |
504 | closure_sync(&cl); |
505 | } | |
506 | ||
57943511 | 507 | static void btree_node_write_work(struct work_struct *w) |
cafe5635 KO |
508 | { |
509 | struct btree *b = container_of(to_delayed_work(w), struct btree, work); | |
510 | ||
2a285686 | 511 | mutex_lock(&b->write_lock); |
cafe5635 | 512 | if (btree_node_dirty(b)) |
2a285686 KO |
513 | __bch_btree_node_write(b, NULL); |
514 | mutex_unlock(&b->write_lock); | |
cafe5635 KO |
515 | } |
516 | ||
c18536a7 | 517 | static void bch_btree_leaf_dirty(struct btree *b, atomic_t *journal_ref) |
cafe5635 | 518 | { |
ee811287 | 519 | struct bset *i = btree_bset_last(b); |
cafe5635 KO |
520 | struct btree_write *w = btree_current_write(b); |
521 | ||
2a285686 KO |
522 | lockdep_assert_held(&b->write_lock); |
523 | ||
57943511 KO |
524 | BUG_ON(!b->written); |
525 | BUG_ON(!i->keys); | |
cafe5635 | 526 | |
57943511 | 527 | if (!btree_node_dirty(b)) |
56b30770 | 528 | schedule_delayed_work(&b->work, 30 * HZ); |
cafe5635 | 529 | |
57943511 | 530 | set_btree_node_dirty(b); |
cafe5635 | 531 | |
c18536a7 | 532 | if (journal_ref) { |
cafe5635 | 533 | if (w->journal && |
c18536a7 | 534 | journal_pin_cmp(b->c, w->journal, journal_ref)) { |
cafe5635 KO |
535 | atomic_dec_bug(w->journal); |
536 | w->journal = NULL; | |
537 | } | |
538 | ||
539 | if (!w->journal) { | |
c18536a7 | 540 | w->journal = journal_ref; |
cafe5635 KO |
541 | atomic_inc(w->journal); |
542 | } | |
543 | } | |
544 | ||
cafe5635 | 545 | /* Force write if set is too big */ |
57943511 KO |
546 | if (set_bytes(i) > PAGE_SIZE - 48 && |
547 | !current->bio_list) | |
548 | bch_btree_node_write(b, NULL); | |
cafe5635 KO |
549 | } |
550 | ||
551 | /* | |
552 | * Btree in memory cache - allocation/freeing | |
553 | * mca -> memory cache | |
554 | */ | |
555 | ||
cafe5635 KO |
556 | #define mca_reserve(c) (((c->root && c->root->level) \ |
557 | ? c->root->level : 1) * 8 + 16) | |
558 | #define mca_can_free(c) \ | |
0a63b66d | 559 | max_t(int, 0, c->btree_cache_used - mca_reserve(c)) |
cafe5635 KO |
560 | |
561 | static void mca_data_free(struct btree *b) | |
562 | { | |
cb7a583e | 563 | BUG_ON(b->io_mutex.count != 1); |
cafe5635 | 564 | |
a85e968e | 565 | bch_btree_keys_free(&b->keys); |
cafe5635 | 566 | |
0a63b66d | 567 | b->c->btree_cache_used--; |
ee811287 | 568 | list_move(&b->list, &b->c->btree_cache_freed); |
cafe5635 KO |
569 | } |
570 | ||
571 | static void mca_bucket_free(struct btree *b) | |
572 | { | |
573 | BUG_ON(btree_node_dirty(b)); | |
574 | ||
575 | b->key.ptr[0] = 0; | |
576 | hlist_del_init_rcu(&b->hash); | |
577 | list_move(&b->list, &b->c->btree_cache_freeable); | |
578 | } | |
579 | ||
580 | static unsigned btree_order(struct bkey *k) | |
581 | { | |
582 | return ilog2(KEY_SIZE(k) / PAGE_SECTORS ?: 1); | |
583 | } | |
584 | ||
585 | static void mca_data_alloc(struct btree *b, struct bkey *k, gfp_t gfp) | |
586 | { | |
a85e968e | 587 | if (!bch_btree_keys_alloc(&b->keys, |
ee811287 KO |
588 | max_t(unsigned, |
589 | ilog2(b->c->btree_pages), | |
590 | btree_order(k)), | |
591 | gfp)) { | |
0a63b66d | 592 | b->c->btree_cache_used++; |
ee811287 KO |
593 | list_move(&b->list, &b->c->btree_cache); |
594 | } else { | |
595 | list_move(&b->list, &b->c->btree_cache_freed); | |
596 | } | |
cafe5635 KO |
597 | } |
598 | ||
599 | static struct btree *mca_bucket_alloc(struct cache_set *c, | |
600 | struct bkey *k, gfp_t gfp) | |
601 | { | |
602 | struct btree *b = kzalloc(sizeof(struct btree), gfp); | |
603 | if (!b) | |
604 | return NULL; | |
605 | ||
606 | init_rwsem(&b->lock); | |
607 | lockdep_set_novalidate_class(&b->lock); | |
2a285686 KO |
608 | mutex_init(&b->write_lock); |
609 | lockdep_set_novalidate_class(&b->write_lock); | |
cafe5635 | 610 | INIT_LIST_HEAD(&b->list); |
57943511 | 611 | INIT_DELAYED_WORK(&b->work, btree_node_write_work); |
cafe5635 | 612 | b->c = c; |
cb7a583e | 613 | sema_init(&b->io_mutex, 1); |
cafe5635 KO |
614 | |
615 | mca_data_alloc(b, k, gfp); | |
616 | return b; | |
617 | } | |
618 | ||
e8e1d468 | 619 | static int mca_reap(struct btree *b, unsigned min_order, bool flush) |
cafe5635 | 620 | { |
e8e1d468 KO |
621 | struct closure cl; |
622 | ||
623 | closure_init_stack(&cl); | |
cafe5635 KO |
624 | lockdep_assert_held(&b->c->bucket_lock); |
625 | ||
626 | if (!down_write_trylock(&b->lock)) | |
627 | return -ENOMEM; | |
628 | ||
a85e968e | 629 | BUG_ON(btree_node_dirty(b) && !b->keys.set[0].data); |
e8e1d468 | 630 | |
a85e968e | 631 | if (b->keys.page_order < min_order) |
cb7a583e KO |
632 | goto out_unlock; |
633 | ||
634 | if (!flush) { | |
635 | if (btree_node_dirty(b)) | |
636 | goto out_unlock; | |
637 | ||
638 | if (down_trylock(&b->io_mutex)) | |
639 | goto out_unlock; | |
640 | up(&b->io_mutex); | |
cafe5635 KO |
641 | } |
642 | ||
2a285686 | 643 | mutex_lock(&b->write_lock); |
f269af5a | 644 | if (btree_node_dirty(b)) |
2a285686 KO |
645 | __bch_btree_node_write(b, &cl); |
646 | mutex_unlock(&b->write_lock); | |
647 | ||
648 | closure_sync(&cl); | |
cafe5635 | 649 | |
e8e1d468 | 650 | /* wait for any in flight btree write */ |
cb7a583e KO |
651 | down(&b->io_mutex); |
652 | up(&b->io_mutex); | |
e8e1d468 | 653 | |
cafe5635 | 654 | return 0; |
cb7a583e KO |
655 | out_unlock: |
656 | rw_unlock(true, b); | |
657 | return -ENOMEM; | |
cafe5635 KO |
658 | } |
659 | ||
7dc19d5a DC |
660 | static unsigned long bch_mca_scan(struct shrinker *shrink, |
661 | struct shrink_control *sc) | |
cafe5635 KO |
662 | { |
663 | struct cache_set *c = container_of(shrink, struct cache_set, shrink); | |
664 | struct btree *b, *t; | |
665 | unsigned long i, nr = sc->nr_to_scan; | |
7dc19d5a | 666 | unsigned long freed = 0; |
cafe5635 KO |
667 | |
668 | if (c->shrinker_disabled) | |
7dc19d5a | 669 | return SHRINK_STOP; |
cafe5635 | 670 | |
0a63b66d | 671 | if (c->btree_cache_alloc_lock) |
7dc19d5a | 672 | return SHRINK_STOP; |
cafe5635 KO |
673 | |
674 | /* Return -1 if we can't do anything right now */ | |
a698e08c | 675 | if (sc->gfp_mask & __GFP_IO) |
cafe5635 KO |
676 | mutex_lock(&c->bucket_lock); |
677 | else if (!mutex_trylock(&c->bucket_lock)) | |
678 | return -1; | |
679 | ||
36c9ea98 KO |
680 | /* |
681 | * It's _really_ critical that we don't free too many btree nodes - we | |
682 | * have to always leave ourselves a reserve. The reserve is how we | |
683 | * guarantee that allocating memory for a new btree node can always | |
684 | * succeed, so that inserting keys into the btree can always succeed and | |
685 | * IO can always make forward progress: | |
686 | */ | |
cafe5635 KO |
687 | nr /= c->btree_pages; |
688 | nr = min_t(unsigned long, nr, mca_can_free(c)); | |
689 | ||
690 | i = 0; | |
691 | list_for_each_entry_safe(b, t, &c->btree_cache_freeable, list) { | |
7dc19d5a | 692 | if (freed >= nr) |
cafe5635 KO |
693 | break; |
694 | ||
695 | if (++i > 3 && | |
e8e1d468 | 696 | !mca_reap(b, 0, false)) { |
cafe5635 KO |
697 | mca_data_free(b); |
698 | rw_unlock(true, b); | |
7dc19d5a | 699 | freed++; |
cafe5635 KO |
700 | } |
701 | } | |
702 | ||
0a63b66d | 703 | for (i = 0; (nr--) && i < c->btree_cache_used; i++) { |
b0f32a56 KO |
704 | if (list_empty(&c->btree_cache)) |
705 | goto out; | |
706 | ||
cafe5635 KO |
707 | b = list_first_entry(&c->btree_cache, struct btree, list); |
708 | list_rotate_left(&c->btree_cache); | |
709 | ||
710 | if (!b->accessed && | |
e8e1d468 | 711 | !mca_reap(b, 0, false)) { |
cafe5635 KO |
712 | mca_bucket_free(b); |
713 | mca_data_free(b); | |
714 | rw_unlock(true, b); | |
7dc19d5a | 715 | freed++; |
cafe5635 KO |
716 | } else |
717 | b->accessed = 0; | |
718 | } | |
719 | out: | |
cafe5635 | 720 | mutex_unlock(&c->bucket_lock); |
7dc19d5a DC |
721 | return freed; |
722 | } | |
723 | ||
724 | static unsigned long bch_mca_count(struct shrinker *shrink, | |
725 | struct shrink_control *sc) | |
726 | { | |
727 | struct cache_set *c = container_of(shrink, struct cache_set, shrink); | |
728 | ||
729 | if (c->shrinker_disabled) | |
730 | return 0; | |
731 | ||
0a63b66d | 732 | if (c->btree_cache_alloc_lock) |
7dc19d5a DC |
733 | return 0; |
734 | ||
735 | return mca_can_free(c) * c->btree_pages; | |
cafe5635 KO |
736 | } |
737 | ||
738 | void bch_btree_cache_free(struct cache_set *c) | |
739 | { | |
740 | struct btree *b; | |
741 | struct closure cl; | |
742 | closure_init_stack(&cl); | |
743 | ||
744 | if (c->shrink.list.next) | |
745 | unregister_shrinker(&c->shrink); | |
746 | ||
747 | mutex_lock(&c->bucket_lock); | |
748 | ||
749 | #ifdef CONFIG_BCACHE_DEBUG | |
750 | if (c->verify_data) | |
751 | list_move(&c->verify_data->list, &c->btree_cache); | |
78b77bf8 KO |
752 | |
753 | free_pages((unsigned long) c->verify_ondisk, ilog2(bucket_pages(c))); | |
cafe5635 KO |
754 | #endif |
755 | ||
756 | list_splice(&c->btree_cache_freeable, | |
757 | &c->btree_cache); | |
758 | ||
759 | while (!list_empty(&c->btree_cache)) { | |
760 | b = list_first_entry(&c->btree_cache, struct btree, list); | |
761 | ||
762 | if (btree_node_dirty(b)) | |
763 | btree_complete_write(b, btree_current_write(b)); | |
764 | clear_bit(BTREE_NODE_dirty, &b->flags); | |
765 | ||
766 | mca_data_free(b); | |
767 | } | |
768 | ||
769 | while (!list_empty(&c->btree_cache_freed)) { | |
770 | b = list_first_entry(&c->btree_cache_freed, | |
771 | struct btree, list); | |
772 | list_del(&b->list); | |
773 | cancel_delayed_work_sync(&b->work); | |
774 | kfree(b); | |
775 | } | |
776 | ||
777 | mutex_unlock(&c->bucket_lock); | |
778 | } | |
779 | ||
780 | int bch_btree_cache_alloc(struct cache_set *c) | |
781 | { | |
782 | unsigned i; | |
783 | ||
cafe5635 | 784 | for (i = 0; i < mca_reserve(c); i++) |
72a44517 KO |
785 | if (!mca_bucket_alloc(c, &ZERO_KEY, GFP_KERNEL)) |
786 | return -ENOMEM; | |
cafe5635 KO |
787 | |
788 | list_splice_init(&c->btree_cache, | |
789 | &c->btree_cache_freeable); | |
790 | ||
791 | #ifdef CONFIG_BCACHE_DEBUG | |
792 | mutex_init(&c->verify_lock); | |
793 | ||
78b77bf8 KO |
794 | c->verify_ondisk = (void *) |
795 | __get_free_pages(GFP_KERNEL, ilog2(bucket_pages(c))); | |
796 | ||
cafe5635 KO |
797 | c->verify_data = mca_bucket_alloc(c, &ZERO_KEY, GFP_KERNEL); |
798 | ||
799 | if (c->verify_data && | |
a85e968e | 800 | c->verify_data->keys.set->data) |
cafe5635 KO |
801 | list_del_init(&c->verify_data->list); |
802 | else | |
803 | c->verify_data = NULL; | |
804 | #endif | |
805 | ||
7dc19d5a DC |
806 | c->shrink.count_objects = bch_mca_count; |
807 | c->shrink.scan_objects = bch_mca_scan; | |
cafe5635 KO |
808 | c->shrink.seeks = 4; |
809 | c->shrink.batch = c->btree_pages * 2; | |
810 | register_shrinker(&c->shrink); | |
811 | ||
812 | return 0; | |
813 | } | |
814 | ||
815 | /* Btree in memory cache - hash table */ | |
816 | ||
817 | static struct hlist_head *mca_hash(struct cache_set *c, struct bkey *k) | |
818 | { | |
819 | return &c->bucket_hash[hash_32(PTR_HASH(c, k), BUCKET_HASH_BITS)]; | |
820 | } | |
821 | ||
822 | static struct btree *mca_find(struct cache_set *c, struct bkey *k) | |
823 | { | |
824 | struct btree *b; | |
825 | ||
826 | rcu_read_lock(); | |
827 | hlist_for_each_entry_rcu(b, mca_hash(c, k), hash) | |
828 | if (PTR_HASH(c, &b->key) == PTR_HASH(c, k)) | |
829 | goto out; | |
830 | b = NULL; | |
831 | out: | |
832 | rcu_read_unlock(); | |
833 | return b; | |
834 | } | |
835 | ||
0a63b66d KO |
836 | static int mca_cannibalize_lock(struct cache_set *c, struct btree_op *op) |
837 | { | |
838 | struct task_struct *old; | |
839 | ||
840 | old = cmpxchg(&c->btree_cache_alloc_lock, NULL, current); | |
841 | if (old && old != current) { | |
842 | if (op) | |
843 | prepare_to_wait(&c->btree_cache_wait, &op->wait, | |
844 | TASK_UNINTERRUPTIBLE); | |
845 | return -EINTR; | |
846 | } | |
847 | ||
848 | return 0; | |
849 | } | |
850 | ||
851 | static struct btree *mca_cannibalize(struct cache_set *c, struct btree_op *op, | |
852 | struct bkey *k) | |
cafe5635 | 853 | { |
e8e1d468 | 854 | struct btree *b; |
cafe5635 | 855 | |
c37511b8 KO |
856 | trace_bcache_btree_cache_cannibalize(c); |
857 | ||
0a63b66d KO |
858 | if (mca_cannibalize_lock(c, op)) |
859 | return ERR_PTR(-EINTR); | |
cafe5635 | 860 | |
e8e1d468 KO |
861 | list_for_each_entry_reverse(b, &c->btree_cache, list) |
862 | if (!mca_reap(b, btree_order(k), false)) | |
863 | return b; | |
cafe5635 | 864 | |
e8e1d468 KO |
865 | list_for_each_entry_reverse(b, &c->btree_cache, list) |
866 | if (!mca_reap(b, btree_order(k), true)) | |
867 | return b; | |
cafe5635 | 868 | |
0a63b66d | 869 | WARN(1, "btree cache cannibalize failed\n"); |
e8e1d468 | 870 | return ERR_PTR(-ENOMEM); |
cafe5635 KO |
871 | } |
872 | ||
873 | /* | |
874 | * We can only have one thread cannibalizing other cached btree nodes at a time, | |
875 | * or we'll deadlock. We use an open coded mutex to ensure that, which a | |
876 | * cannibalize_bucket() will take. This means every time we unlock the root of | |
877 | * the btree, we need to release this lock if we have it held. | |
878 | */ | |
df8e8970 | 879 | static void bch_cannibalize_unlock(struct cache_set *c) |
cafe5635 | 880 | { |
0a63b66d KO |
881 | if (c->btree_cache_alloc_lock == current) { |
882 | c->btree_cache_alloc_lock = NULL; | |
883 | wake_up(&c->btree_cache_wait); | |
cafe5635 KO |
884 | } |
885 | } | |
886 | ||
0a63b66d KO |
887 | static struct btree *mca_alloc(struct cache_set *c, struct btree_op *op, |
888 | struct bkey *k, int level) | |
cafe5635 KO |
889 | { |
890 | struct btree *b; | |
891 | ||
e8e1d468 KO |
892 | BUG_ON(current->bio_list); |
893 | ||
cafe5635 KO |
894 | lockdep_assert_held(&c->bucket_lock); |
895 | ||
896 | if (mca_find(c, k)) | |
897 | return NULL; | |
898 | ||
899 | /* btree_free() doesn't free memory; it sticks the node on the end of | |
900 | * the list. Check if there's any freed nodes there: | |
901 | */ | |
902 | list_for_each_entry(b, &c->btree_cache_freeable, list) | |
e8e1d468 | 903 | if (!mca_reap(b, btree_order(k), false)) |
cafe5635 KO |
904 | goto out; |
905 | ||
906 | /* We never free struct btree itself, just the memory that holds the on | |
907 | * disk node. Check the freed list before allocating a new one: | |
908 | */ | |
909 | list_for_each_entry(b, &c->btree_cache_freed, list) | |
e8e1d468 | 910 | if (!mca_reap(b, 0, false)) { |
cafe5635 | 911 | mca_data_alloc(b, k, __GFP_NOWARN|GFP_NOIO); |
a85e968e | 912 | if (!b->keys.set[0].data) |
cafe5635 KO |
913 | goto err; |
914 | else | |
915 | goto out; | |
916 | } | |
917 | ||
918 | b = mca_bucket_alloc(c, k, __GFP_NOWARN|GFP_NOIO); | |
919 | if (!b) | |
920 | goto err; | |
921 | ||
922 | BUG_ON(!down_write_trylock(&b->lock)); | |
a85e968e | 923 | if (!b->keys.set->data) |
cafe5635 KO |
924 | goto err; |
925 | out: | |
cb7a583e | 926 | BUG_ON(b->io_mutex.count != 1); |
cafe5635 KO |
927 | |
928 | bkey_copy(&b->key, k); | |
929 | list_move(&b->list, &c->btree_cache); | |
930 | hlist_del_init_rcu(&b->hash); | |
931 | hlist_add_head_rcu(&b->hash, mca_hash(c, k)); | |
932 | ||
933 | lock_set_subclass(&b->lock.dep_map, level + 1, _THIS_IP_); | |
d6fd3b11 | 934 | b->parent = (void *) ~0UL; |
a85e968e KO |
935 | b->flags = 0; |
936 | b->written = 0; | |
937 | b->level = level; | |
cafe5635 | 938 | |
65d45231 | 939 | if (!b->level) |
a85e968e KO |
940 | bch_btree_keys_init(&b->keys, &bch_extent_keys_ops, |
941 | &b->c->expensive_debug_checks); | |
65d45231 | 942 | else |
a85e968e KO |
943 | bch_btree_keys_init(&b->keys, &bch_btree_keys_ops, |
944 | &b->c->expensive_debug_checks); | |
cafe5635 KO |
945 | |
946 | return b; | |
947 | err: | |
948 | if (b) | |
949 | rw_unlock(true, b); | |
950 | ||
0a63b66d | 951 | b = mca_cannibalize(c, op, k); |
cafe5635 KO |
952 | if (!IS_ERR(b)) |
953 | goto out; | |
954 | ||
955 | return b; | |
956 | } | |
957 | ||
958 | /** | |
959 | * bch_btree_node_get - find a btree node in the cache and lock it, reading it | |
960 | * in from disk if necessary. | |
961 | * | |
b54d6934 | 962 | * If IO is necessary and running under generic_make_request, returns -EAGAIN. |
cafe5635 KO |
963 | * |
964 | * The btree node will have either a read or a write lock held, depending on | |
965 | * level and op->lock. | |
966 | */ | |
0a63b66d | 967 | struct btree *bch_btree_node_get(struct cache_set *c, struct btree_op *op, |
2452cc89 SP |
968 | struct bkey *k, int level, bool write, |
969 | struct btree *parent) | |
cafe5635 KO |
970 | { |
971 | int i = 0; | |
cafe5635 KO |
972 | struct btree *b; |
973 | ||
974 | BUG_ON(level < 0); | |
975 | retry: | |
976 | b = mca_find(c, k); | |
977 | ||
978 | if (!b) { | |
57943511 KO |
979 | if (current->bio_list) |
980 | return ERR_PTR(-EAGAIN); | |
981 | ||
cafe5635 | 982 | mutex_lock(&c->bucket_lock); |
0a63b66d | 983 | b = mca_alloc(c, op, k, level); |
cafe5635 KO |
984 | mutex_unlock(&c->bucket_lock); |
985 | ||
986 | if (!b) | |
987 | goto retry; | |
988 | if (IS_ERR(b)) | |
989 | return b; | |
990 | ||
57943511 | 991 | bch_btree_node_read(b); |
cafe5635 KO |
992 | |
993 | if (!write) | |
994 | downgrade_write(&b->lock); | |
995 | } else { | |
996 | rw_lock(write, b, level); | |
997 | if (PTR_HASH(c, &b->key) != PTR_HASH(c, k)) { | |
998 | rw_unlock(write, b); | |
999 | goto retry; | |
1000 | } | |
1001 | BUG_ON(b->level != level); | |
1002 | } | |
1003 | ||
2452cc89 | 1004 | b->parent = parent; |
cafe5635 KO |
1005 | b->accessed = 1; |
1006 | ||
a85e968e KO |
1007 | for (; i <= b->keys.nsets && b->keys.set[i].size; i++) { |
1008 | prefetch(b->keys.set[i].tree); | |
1009 | prefetch(b->keys.set[i].data); | |
cafe5635 KO |
1010 | } |
1011 | ||
a85e968e KO |
1012 | for (; i <= b->keys.nsets; i++) |
1013 | prefetch(b->keys.set[i].data); | |
cafe5635 | 1014 | |
57943511 | 1015 | if (btree_node_io_error(b)) { |
cafe5635 | 1016 | rw_unlock(write, b); |
57943511 KO |
1017 | return ERR_PTR(-EIO); |
1018 | } | |
1019 | ||
1020 | BUG_ON(!b->written); | |
cafe5635 KO |
1021 | |
1022 | return b; | |
1023 | } | |
1024 | ||
2452cc89 | 1025 | static void btree_node_prefetch(struct btree *parent, struct bkey *k) |
cafe5635 KO |
1026 | { |
1027 | struct btree *b; | |
1028 | ||
2452cc89 SP |
1029 | mutex_lock(&parent->c->bucket_lock); |
1030 | b = mca_alloc(parent->c, NULL, k, parent->level - 1); | |
1031 | mutex_unlock(&parent->c->bucket_lock); | |
cafe5635 KO |
1032 | |
1033 | if (!IS_ERR_OR_NULL(b)) { | |
2452cc89 | 1034 | b->parent = parent; |
57943511 | 1035 | bch_btree_node_read(b); |
cafe5635 KO |
1036 | rw_unlock(true, b); |
1037 | } | |
1038 | } | |
1039 | ||
1040 | /* Btree alloc */ | |
1041 | ||
e8e1d468 | 1042 | static void btree_node_free(struct btree *b) |
cafe5635 | 1043 | { |
c37511b8 KO |
1044 | trace_bcache_btree_node_free(b); |
1045 | ||
cafe5635 | 1046 | BUG_ON(b == b->c->root); |
cafe5635 | 1047 | |
2a285686 KO |
1048 | mutex_lock(&b->write_lock); |
1049 | ||
cafe5635 KO |
1050 | if (btree_node_dirty(b)) |
1051 | btree_complete_write(b, btree_current_write(b)); | |
1052 | clear_bit(BTREE_NODE_dirty, &b->flags); | |
1053 | ||
2a285686 KO |
1054 | mutex_unlock(&b->write_lock); |
1055 | ||
cafe5635 KO |
1056 | cancel_delayed_work(&b->work); |
1057 | ||
1058 | mutex_lock(&b->c->bucket_lock); | |
cafe5635 KO |
1059 | bch_bucket_free(b->c, &b->key); |
1060 | mca_bucket_free(b); | |
1061 | mutex_unlock(&b->c->bucket_lock); | |
1062 | } | |
1063 | ||
c5aa4a31 | 1064 | struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op, |
2452cc89 SP |
1065 | int level, bool wait, |
1066 | struct btree *parent) | |
cafe5635 KO |
1067 | { |
1068 | BKEY_PADDED(key) k; | |
1069 | struct btree *b = ERR_PTR(-EAGAIN); | |
1070 | ||
1071 | mutex_lock(&c->bucket_lock); | |
1072 | retry: | |
c5aa4a31 | 1073 | if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, wait)) |
cafe5635 KO |
1074 | goto err; |
1075 | ||
3a3b6a4e | 1076 | bkey_put(c, &k.key); |
cafe5635 KO |
1077 | SET_KEY_SIZE(&k.key, c->btree_pages * PAGE_SECTORS); |
1078 | ||
0a63b66d | 1079 | b = mca_alloc(c, op, &k.key, level); |
cafe5635 KO |
1080 | if (IS_ERR(b)) |
1081 | goto err_free; | |
1082 | ||
1083 | if (!b) { | |
b1a67b0f KO |
1084 | cache_bug(c, |
1085 | "Tried to allocate bucket that was in btree cache"); | |
cafe5635 KO |
1086 | goto retry; |
1087 | } | |
1088 | ||
cafe5635 | 1089 | b->accessed = 1; |
2452cc89 | 1090 | b->parent = parent; |
a85e968e | 1091 | bch_bset_init_next(&b->keys, b->keys.set->data, bset_magic(&b->c->sb)); |
cafe5635 KO |
1092 | |
1093 | mutex_unlock(&c->bucket_lock); | |
c37511b8 KO |
1094 | |
1095 | trace_bcache_btree_node_alloc(b); | |
cafe5635 KO |
1096 | return b; |
1097 | err_free: | |
1098 | bch_bucket_free(c, &k.key); | |
cafe5635 KO |
1099 | err: |
1100 | mutex_unlock(&c->bucket_lock); | |
c37511b8 | 1101 | |
913dc33f | 1102 | trace_bcache_btree_node_alloc_fail(c); |
cafe5635 KO |
1103 | return b; |
1104 | } | |
1105 | ||
c5aa4a31 | 1106 | static struct btree *bch_btree_node_alloc(struct cache_set *c, |
2452cc89 SP |
1107 | struct btree_op *op, int level, |
1108 | struct btree *parent) | |
c5aa4a31 | 1109 | { |
2452cc89 | 1110 | return __bch_btree_node_alloc(c, op, level, op != NULL, parent); |
c5aa4a31 SP |
1111 | } |
1112 | ||
0a63b66d KO |
1113 | static struct btree *btree_node_alloc_replacement(struct btree *b, |
1114 | struct btree_op *op) | |
cafe5635 | 1115 | { |
2452cc89 | 1116 | struct btree *n = bch_btree_node_alloc(b->c, op, b->level, b->parent); |
67539e85 | 1117 | if (!IS_ERR_OR_NULL(n)) { |
2a285686 | 1118 | mutex_lock(&n->write_lock); |
89ebb4a2 | 1119 | bch_btree_sort_into(&b->keys, &n->keys, &b->c->sort); |
67539e85 | 1120 | bkey_copy_key(&n->key, &b->key); |
2a285686 | 1121 | mutex_unlock(&n->write_lock); |
67539e85 | 1122 | } |
cafe5635 KO |
1123 | |
1124 | return n; | |
1125 | } | |
1126 | ||
8835c123 KO |
1127 | static void make_btree_freeing_key(struct btree *b, struct bkey *k) |
1128 | { | |
1129 | unsigned i; | |
1130 | ||
05335cff KO |
1131 | mutex_lock(&b->c->bucket_lock); |
1132 | ||
1133 | atomic_inc(&b->c->prio_blocked); | |
1134 | ||
8835c123 KO |
1135 | bkey_copy(k, &b->key); |
1136 | bkey_copy_key(k, &ZERO_KEY); | |
1137 | ||
05335cff KO |
1138 | for (i = 0; i < KEY_PTRS(k); i++) |
1139 | SET_PTR_GEN(k, i, | |
1140 | bch_inc_gen(PTR_CACHE(b->c, &b->key, i), | |
1141 | PTR_BUCKET(b->c, &b->key, i))); | |
8835c123 | 1142 | |
05335cff | 1143 | mutex_unlock(&b->c->bucket_lock); |
8835c123 KO |
1144 | } |
1145 | ||
78365411 KO |
1146 | static int btree_check_reserve(struct btree *b, struct btree_op *op) |
1147 | { | |
1148 | struct cache_set *c = b->c; | |
1149 | struct cache *ca; | |
0a63b66d | 1150 | unsigned i, reserve = (c->root->level - b->level) * 2 + 1; |
78365411 KO |
1151 | |
1152 | mutex_lock(&c->bucket_lock); | |
1153 | ||
1154 | for_each_cache(ca, c, i) | |
1155 | if (fifo_used(&ca->free[RESERVE_BTREE]) < reserve) { | |
1156 | if (op) | |
0a63b66d | 1157 | prepare_to_wait(&c->btree_cache_wait, &op->wait, |
78365411 | 1158 | TASK_UNINTERRUPTIBLE); |
0a63b66d KO |
1159 | mutex_unlock(&c->bucket_lock); |
1160 | return -EINTR; | |
78365411 KO |
1161 | } |
1162 | ||
1163 | mutex_unlock(&c->bucket_lock); | |
0a63b66d KO |
1164 | |
1165 | return mca_cannibalize_lock(b->c, op); | |
78365411 KO |
1166 | } |
1167 | ||
cafe5635 KO |
1168 | /* Garbage collection */ |
1169 | ||
487dded8 KO |
1170 | static uint8_t __bch_btree_mark_key(struct cache_set *c, int level, |
1171 | struct bkey *k) | |
cafe5635 KO |
1172 | { |
1173 | uint8_t stale = 0; | |
1174 | unsigned i; | |
1175 | struct bucket *g; | |
1176 | ||
1177 | /* | |
1178 | * ptr_invalid() can't return true for the keys that mark btree nodes as | |
1179 | * freed, but since ptr_bad() returns true we'll never actually use them | |
1180 | * for anything and thus we don't want mark their pointers here | |
1181 | */ | |
1182 | if (!bkey_cmp(k, &ZERO_KEY)) | |
1183 | return stale; | |
1184 | ||
1185 | for (i = 0; i < KEY_PTRS(k); i++) { | |
1186 | if (!ptr_available(c, k, i)) | |
1187 | continue; | |
1188 | ||
1189 | g = PTR_BUCKET(c, k, i); | |
1190 | ||
3a2fd9d5 KO |
1191 | if (gen_after(g->last_gc, PTR_GEN(k, i))) |
1192 | g->last_gc = PTR_GEN(k, i); | |
cafe5635 KO |
1193 | |
1194 | if (ptr_stale(c, k, i)) { | |
1195 | stale = max(stale, ptr_stale(c, k, i)); | |
1196 | continue; | |
1197 | } | |
1198 | ||
1199 | cache_bug_on(GC_MARK(g) && | |
1200 | (GC_MARK(g) == GC_MARK_METADATA) != (level != 0), | |
1201 | c, "inconsistent ptrs: mark = %llu, level = %i", | |
1202 | GC_MARK(g), level); | |
1203 | ||
1204 | if (level) | |
1205 | SET_GC_MARK(g, GC_MARK_METADATA); | |
1206 | else if (KEY_DIRTY(k)) | |
1207 | SET_GC_MARK(g, GC_MARK_DIRTY); | |
4fe6a816 KO |
1208 | else if (!GC_MARK(g)) |
1209 | SET_GC_MARK(g, GC_MARK_RECLAIMABLE); | |
cafe5635 KO |
1210 | |
1211 | /* guard against overflow */ | |
1212 | SET_GC_SECTORS_USED(g, min_t(unsigned, | |
1213 | GC_SECTORS_USED(g) + KEY_SIZE(k), | |
94717447 | 1214 | MAX_GC_SECTORS_USED)); |
cafe5635 KO |
1215 | |
1216 | BUG_ON(!GC_SECTORS_USED(g)); | |
1217 | } | |
1218 | ||
1219 | return stale; | |
1220 | } | |
1221 | ||
1222 | #define btree_mark_key(b, k) __bch_btree_mark_key(b->c, b->level, k) | |
1223 | ||
487dded8 KO |
1224 | void bch_initial_mark_key(struct cache_set *c, int level, struct bkey *k) |
1225 | { | |
1226 | unsigned i; | |
1227 | ||
1228 | for (i = 0; i < KEY_PTRS(k); i++) | |
1229 | if (ptr_available(c, k, i) && | |
1230 | !ptr_stale(c, k, i)) { | |
1231 | struct bucket *b = PTR_BUCKET(c, k, i); | |
1232 | ||
1233 | b->gen = PTR_GEN(k, i); | |
1234 | ||
1235 | if (level && bkey_cmp(k, &ZERO_KEY)) | |
1236 | b->prio = BTREE_PRIO; | |
1237 | else if (!level && b->prio == BTREE_PRIO) | |
1238 | b->prio = INITIAL_PRIO; | |
1239 | } | |
1240 | ||
1241 | __bch_btree_mark_key(c, level, k); | |
1242 | } | |
1243 | ||
a1f0358b | 1244 | static bool btree_gc_mark_node(struct btree *b, struct gc_stat *gc) |
cafe5635 KO |
1245 | { |
1246 | uint8_t stale = 0; | |
a1f0358b | 1247 | unsigned keys = 0, good_keys = 0; |
cafe5635 KO |
1248 | struct bkey *k; |
1249 | struct btree_iter iter; | |
1250 | struct bset_tree *t; | |
1251 | ||
1252 | gc->nodes++; | |
1253 | ||
c052dd9a | 1254 | for_each_key_filter(&b->keys, k, &iter, bch_ptr_invalid) { |
cafe5635 | 1255 | stale = max(stale, btree_mark_key(b, k)); |
a1f0358b | 1256 | keys++; |
cafe5635 | 1257 | |
a85e968e | 1258 | if (bch_ptr_bad(&b->keys, k)) |
cafe5635 KO |
1259 | continue; |
1260 | ||
cafe5635 KO |
1261 | gc->key_bytes += bkey_u64s(k); |
1262 | gc->nkeys++; | |
a1f0358b | 1263 | good_keys++; |
cafe5635 KO |
1264 | |
1265 | gc->data += KEY_SIZE(k); | |
cafe5635 KO |
1266 | } |
1267 | ||
a85e968e | 1268 | for (t = b->keys.set; t <= &b->keys.set[b->keys.nsets]; t++) |
cafe5635 | 1269 | btree_bug_on(t->size && |
a85e968e | 1270 | bset_written(&b->keys, t) && |
cafe5635 KO |
1271 | bkey_cmp(&b->key, &t->end) < 0, |
1272 | b, "found short btree key in gc"); | |
1273 | ||
a1f0358b KO |
1274 | if (b->c->gc_always_rewrite) |
1275 | return true; | |
cafe5635 | 1276 | |
a1f0358b KO |
1277 | if (stale > 10) |
1278 | return true; | |
cafe5635 | 1279 | |
a1f0358b KO |
1280 | if ((keys - good_keys) * 2 > keys) |
1281 | return true; | |
cafe5635 | 1282 | |
a1f0358b | 1283 | return false; |
cafe5635 KO |
1284 | } |
1285 | ||
a1f0358b | 1286 | #define GC_MERGE_NODES 4U |
cafe5635 KO |
1287 | |
1288 | struct gc_merge_info { | |
1289 | struct btree *b; | |
cafe5635 KO |
1290 | unsigned keys; |
1291 | }; | |
1292 | ||
a1f0358b KO |
1293 | static int bch_btree_insert_node(struct btree *, struct btree_op *, |
1294 | struct keylist *, atomic_t *, struct bkey *); | |
1295 | ||
1296 | static int btree_gc_coalesce(struct btree *b, struct btree_op *op, | |
0a63b66d | 1297 | struct gc_stat *gc, struct gc_merge_info *r) |
cafe5635 | 1298 | { |
a1f0358b KO |
1299 | unsigned i, nodes = 0, keys = 0, blocks; |
1300 | struct btree *new_nodes[GC_MERGE_NODES]; | |
0a63b66d | 1301 | struct keylist keylist; |
b54d6934 | 1302 | struct closure cl; |
a1f0358b | 1303 | struct bkey *k; |
b54d6934 | 1304 | |
0a63b66d KO |
1305 | bch_keylist_init(&keylist); |
1306 | ||
1307 | if (btree_check_reserve(b, NULL)) | |
1308 | return 0; | |
1309 | ||
a1f0358b | 1310 | memset(new_nodes, 0, sizeof(new_nodes)); |
b54d6934 | 1311 | closure_init_stack(&cl); |
cafe5635 | 1312 | |
a1f0358b | 1313 | while (nodes < GC_MERGE_NODES && !IS_ERR_OR_NULL(r[nodes].b)) |
cafe5635 KO |
1314 | keys += r[nodes++].keys; |
1315 | ||
1316 | blocks = btree_default_blocks(b->c) * 2 / 3; | |
1317 | ||
1318 | if (nodes < 2 || | |
a85e968e | 1319 | __set_blocks(b->keys.set[0].data, keys, |
ee811287 | 1320 | block_bytes(b->c)) > blocks * (nodes - 1)) |
a1f0358b | 1321 | return 0; |
cafe5635 | 1322 | |
a1f0358b | 1323 | for (i = 0; i < nodes; i++) { |
0a63b66d | 1324 | new_nodes[i] = btree_node_alloc_replacement(r[i].b, NULL); |
a1f0358b KO |
1325 | if (IS_ERR_OR_NULL(new_nodes[i])) |
1326 | goto out_nocoalesce; | |
cafe5635 KO |
1327 | } |
1328 | ||
0a63b66d KO |
1329 | /* |
1330 | * We have to check the reserve here, after we've allocated our new | |
1331 | * nodes, to make sure the insert below will succeed - we also check | |
1332 | * before as an optimization to potentially avoid a bunch of expensive | |
1333 | * allocs/sorts | |
1334 | */ | |
1335 | if (btree_check_reserve(b, NULL)) | |
1336 | goto out_nocoalesce; | |
1337 | ||
2a285686 KO |
1338 | for (i = 0; i < nodes; i++) |
1339 | mutex_lock(&new_nodes[i]->write_lock); | |
1340 | ||
cafe5635 | 1341 | for (i = nodes - 1; i > 0; --i) { |
ee811287 KO |
1342 | struct bset *n1 = btree_bset_first(new_nodes[i]); |
1343 | struct bset *n2 = btree_bset_first(new_nodes[i - 1]); | |
cafe5635 KO |
1344 | struct bkey *k, *last = NULL; |
1345 | ||
1346 | keys = 0; | |
1347 | ||
a1f0358b KO |
1348 | if (i > 1) { |
1349 | for (k = n2->start; | |
fafff81c | 1350 | k < bset_bkey_last(n2); |
a1f0358b KO |
1351 | k = bkey_next(k)) { |
1352 | if (__set_blocks(n1, n1->keys + keys + | |
ee811287 KO |
1353 | bkey_u64s(k), |
1354 | block_bytes(b->c)) > blocks) | |
a1f0358b KO |
1355 | break; |
1356 | ||
1357 | last = k; | |
1358 | keys += bkey_u64s(k); | |
1359 | } | |
1360 | } else { | |
cafe5635 KO |
1361 | /* |
1362 | * Last node we're not getting rid of - we're getting | |
1363 | * rid of the node at r[0]. Have to try and fit all of | |
1364 | * the remaining keys into this node; we can't ensure | |
1365 | * they will always fit due to rounding and variable | |
1366 | * length keys (shouldn't be possible in practice, | |
1367 | * though) | |
1368 | */ | |
a1f0358b | 1369 | if (__set_blocks(n1, n1->keys + n2->keys, |
ee811287 KO |
1370 | block_bytes(b->c)) > |
1371 | btree_blocks(new_nodes[i])) | |
a1f0358b | 1372 | goto out_nocoalesce; |
cafe5635 KO |
1373 | |
1374 | keys = n2->keys; | |
a1f0358b | 1375 | /* Take the key of the node we're getting rid of */ |
cafe5635 | 1376 | last = &r->b->key; |
a1f0358b | 1377 | } |
cafe5635 | 1378 | |
ee811287 KO |
1379 | BUG_ON(__set_blocks(n1, n1->keys + keys, block_bytes(b->c)) > |
1380 | btree_blocks(new_nodes[i])); | |
cafe5635 | 1381 | |
a1f0358b KO |
1382 | if (last) |
1383 | bkey_copy_key(&new_nodes[i]->key, last); | |
cafe5635 | 1384 | |
fafff81c | 1385 | memcpy(bset_bkey_last(n1), |
cafe5635 | 1386 | n2->start, |
fafff81c | 1387 | (void *) bset_bkey_idx(n2, keys) - (void *) n2->start); |
cafe5635 KO |
1388 | |
1389 | n1->keys += keys; | |
a1f0358b | 1390 | r[i].keys = n1->keys; |
cafe5635 KO |
1391 | |
1392 | memmove(n2->start, | |
fafff81c KO |
1393 | bset_bkey_idx(n2, keys), |
1394 | (void *) bset_bkey_last(n2) - | |
1395 | (void *) bset_bkey_idx(n2, keys)); | |
cafe5635 KO |
1396 | |
1397 | n2->keys -= keys; | |
1398 | ||
0a63b66d | 1399 | if (__bch_keylist_realloc(&keylist, |
085d2a3d | 1400 | bkey_u64s(&new_nodes[i]->key))) |
a1f0358b KO |
1401 | goto out_nocoalesce; |
1402 | ||
1403 | bch_btree_node_write(new_nodes[i], &cl); | |
0a63b66d | 1404 | bch_keylist_add(&keylist, &new_nodes[i]->key); |
cafe5635 KO |
1405 | } |
1406 | ||
2a285686 KO |
1407 | for (i = 0; i < nodes; i++) |
1408 | mutex_unlock(&new_nodes[i]->write_lock); | |
1409 | ||
05335cff KO |
1410 | closure_sync(&cl); |
1411 | ||
1412 | /* We emptied out this node */ | |
1413 | BUG_ON(btree_bset_first(new_nodes[0])->keys); | |
1414 | btree_node_free(new_nodes[0]); | |
1415 | rw_unlock(true, new_nodes[0]); | |
400ffaa2 | 1416 | new_nodes[0] = NULL; |
05335cff | 1417 | |
a1f0358b | 1418 | for (i = 0; i < nodes; i++) { |
0a63b66d | 1419 | if (__bch_keylist_realloc(&keylist, bkey_u64s(&r[i].b->key))) |
a1f0358b | 1420 | goto out_nocoalesce; |
cafe5635 | 1421 | |
0a63b66d KO |
1422 | make_btree_freeing_key(r[i].b, keylist.top); |
1423 | bch_keylist_push(&keylist); | |
a1f0358b | 1424 | } |
cafe5635 | 1425 | |
0a63b66d KO |
1426 | bch_btree_insert_node(b, op, &keylist, NULL, NULL); |
1427 | BUG_ON(!bch_keylist_empty(&keylist)); | |
a1f0358b KO |
1428 | |
1429 | for (i = 0; i < nodes; i++) { | |
1430 | btree_node_free(r[i].b); | |
1431 | rw_unlock(true, r[i].b); | |
1432 | ||
1433 | r[i].b = new_nodes[i]; | |
1434 | } | |
1435 | ||
a1f0358b KO |
1436 | memmove(r, r + 1, sizeof(r[0]) * (nodes - 1)); |
1437 | r[nodes - 1].b = ERR_PTR(-EINTR); | |
1438 | ||
1439 | trace_bcache_btree_gc_coalesce(nodes); | |
cafe5635 | 1440 | gc->nodes--; |
cafe5635 | 1441 | |
0a63b66d KO |
1442 | bch_keylist_free(&keylist); |
1443 | ||
a1f0358b KO |
1444 | /* Invalidated our iterator */ |
1445 | return -EINTR; | |
1446 | ||
1447 | out_nocoalesce: | |
1448 | closure_sync(&cl); | |
0a63b66d | 1449 | bch_keylist_free(&keylist); |
a1f0358b | 1450 | |
0a63b66d | 1451 | while ((k = bch_keylist_pop(&keylist))) |
a1f0358b KO |
1452 | if (!bkey_cmp(k, &ZERO_KEY)) |
1453 | atomic_dec(&b->c->prio_blocked); | |
1454 | ||
1455 | for (i = 0; i < nodes; i++) | |
1456 | if (!IS_ERR_OR_NULL(new_nodes[i])) { | |
1457 | btree_node_free(new_nodes[i]); | |
1458 | rw_unlock(true, new_nodes[i]); | |
1459 | } | |
1460 | return 0; | |
cafe5635 KO |
1461 | } |
1462 | ||
0a63b66d KO |
1463 | static int btree_gc_rewrite_node(struct btree *b, struct btree_op *op, |
1464 | struct btree *replace) | |
1465 | { | |
1466 | struct keylist keys; | |
1467 | struct btree *n; | |
1468 | ||
1469 | if (btree_check_reserve(b, NULL)) | |
1470 | return 0; | |
1471 | ||
1472 | n = btree_node_alloc_replacement(replace, NULL); | |
1473 | ||
1474 | /* recheck reserve after allocating replacement node */ | |
1475 | if (btree_check_reserve(b, NULL)) { | |
1476 | btree_node_free(n); | |
1477 | rw_unlock(true, n); | |
1478 | return 0; | |
1479 | } | |
1480 | ||
1481 | bch_btree_node_write_sync(n); | |
1482 | ||
1483 | bch_keylist_init(&keys); | |
1484 | bch_keylist_add(&keys, &n->key); | |
1485 | ||
1486 | make_btree_freeing_key(replace, keys.top); | |
1487 | bch_keylist_push(&keys); | |
1488 | ||
1489 | bch_btree_insert_node(b, op, &keys, NULL, NULL); | |
1490 | BUG_ON(!bch_keylist_empty(&keys)); | |
1491 | ||
1492 | btree_node_free(replace); | |
1493 | rw_unlock(true, n); | |
1494 | ||
1495 | /* Invalidated our iterator */ | |
1496 | return -EINTR; | |
1497 | } | |
1498 | ||
a1f0358b | 1499 | static unsigned btree_gc_count_keys(struct btree *b) |
cafe5635 | 1500 | { |
a1f0358b KO |
1501 | struct bkey *k; |
1502 | struct btree_iter iter; | |
1503 | unsigned ret = 0; | |
cafe5635 | 1504 | |
c052dd9a | 1505 | for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad) |
a1f0358b KO |
1506 | ret += bkey_u64s(k); |
1507 | ||
1508 | return ret; | |
1509 | } | |
cafe5635 | 1510 | |
a1f0358b KO |
1511 | static int btree_gc_recurse(struct btree *b, struct btree_op *op, |
1512 | struct closure *writes, struct gc_stat *gc) | |
1513 | { | |
a1f0358b KO |
1514 | int ret = 0; |
1515 | bool should_rewrite; | |
a1f0358b | 1516 | struct bkey *k; |
a1f0358b | 1517 | struct btree_iter iter; |
cafe5635 | 1518 | struct gc_merge_info r[GC_MERGE_NODES]; |
2a285686 | 1519 | struct gc_merge_info *i, *last = r + ARRAY_SIZE(r) - 1; |
cafe5635 | 1520 | |
c052dd9a | 1521 | bch_btree_iter_init(&b->keys, &iter, &b->c->gc_done); |
cafe5635 | 1522 | |
2a285686 KO |
1523 | for (i = r; i < r + ARRAY_SIZE(r); i++) |
1524 | i->b = ERR_PTR(-EINTR); | |
cafe5635 | 1525 | |
a1f0358b | 1526 | while (1) { |
a85e968e | 1527 | k = bch_btree_iter_next_filter(&iter, &b->keys, bch_ptr_bad); |
a1f0358b | 1528 | if (k) { |
0a63b66d | 1529 | r->b = bch_btree_node_get(b->c, op, k, b->level - 1, |
2452cc89 | 1530 | true, b); |
a1f0358b KO |
1531 | if (IS_ERR(r->b)) { |
1532 | ret = PTR_ERR(r->b); | |
1533 | break; | |
1534 | } | |
1535 | ||
1536 | r->keys = btree_gc_count_keys(r->b); | |
1537 | ||
0a63b66d | 1538 | ret = btree_gc_coalesce(b, op, gc, r); |
a1f0358b KO |
1539 | if (ret) |
1540 | break; | |
cafe5635 KO |
1541 | } |
1542 | ||
a1f0358b KO |
1543 | if (!last->b) |
1544 | break; | |
cafe5635 | 1545 | |
a1f0358b KO |
1546 | if (!IS_ERR(last->b)) { |
1547 | should_rewrite = btree_gc_mark_node(last->b, gc); | |
0a63b66d KO |
1548 | if (should_rewrite) { |
1549 | ret = btree_gc_rewrite_node(b, op, last->b); | |
1550 | if (ret) | |
a1f0358b | 1551 | break; |
a1f0358b KO |
1552 | } |
1553 | ||
1554 | if (last->b->level) { | |
1555 | ret = btree_gc_recurse(last->b, op, writes, gc); | |
1556 | if (ret) | |
1557 | break; | |
1558 | } | |
cafe5635 | 1559 | |
a1f0358b KO |
1560 | bkey_copy_key(&b->c->gc_done, &last->b->key); |
1561 | ||
1562 | /* | |
1563 | * Must flush leaf nodes before gc ends, since replace | |
1564 | * operations aren't journalled | |
1565 | */ | |
2a285686 | 1566 | mutex_lock(&last->b->write_lock); |
a1f0358b KO |
1567 | if (btree_node_dirty(last->b)) |
1568 | bch_btree_node_write(last->b, writes); | |
2a285686 | 1569 | mutex_unlock(&last->b->write_lock); |
a1f0358b KO |
1570 | rw_unlock(true, last->b); |
1571 | } | |
1572 | ||
1573 | memmove(r + 1, r, sizeof(r[0]) * (GC_MERGE_NODES - 1)); | |
1574 | r->b = NULL; | |
cafe5635 | 1575 | |
cafe5635 KO |
1576 | if (need_resched()) { |
1577 | ret = -EAGAIN; | |
1578 | break; | |
1579 | } | |
cafe5635 KO |
1580 | } |
1581 | ||
2a285686 KO |
1582 | for (i = r; i < r + ARRAY_SIZE(r); i++) |
1583 | if (!IS_ERR_OR_NULL(i->b)) { | |
1584 | mutex_lock(&i->b->write_lock); | |
1585 | if (btree_node_dirty(i->b)) | |
1586 | bch_btree_node_write(i->b, writes); | |
1587 | mutex_unlock(&i->b->write_lock); | |
1588 | rw_unlock(true, i->b); | |
a1f0358b | 1589 | } |
cafe5635 | 1590 | |
cafe5635 KO |
1591 | return ret; |
1592 | } | |
1593 | ||
1594 | static int bch_btree_gc_root(struct btree *b, struct btree_op *op, | |
1595 | struct closure *writes, struct gc_stat *gc) | |
1596 | { | |
1597 | struct btree *n = NULL; | |
a1f0358b KO |
1598 | int ret = 0; |
1599 | bool should_rewrite; | |
cafe5635 | 1600 | |
a1f0358b KO |
1601 | should_rewrite = btree_gc_mark_node(b, gc); |
1602 | if (should_rewrite) { | |
0a63b66d | 1603 | n = btree_node_alloc_replacement(b, NULL); |
cafe5635 | 1604 | |
a1f0358b KO |
1605 | if (!IS_ERR_OR_NULL(n)) { |
1606 | bch_btree_node_write_sync(n); | |
2a285686 | 1607 | |
a1f0358b KO |
1608 | bch_btree_set_root(n); |
1609 | btree_node_free(b); | |
1610 | rw_unlock(true, n); | |
cafe5635 | 1611 | |
a1f0358b KO |
1612 | return -EINTR; |
1613 | } | |
1614 | } | |
cafe5635 | 1615 | |
487dded8 KO |
1616 | __bch_btree_mark_key(b->c, b->level + 1, &b->key); |
1617 | ||
a1f0358b KO |
1618 | if (b->level) { |
1619 | ret = btree_gc_recurse(b, op, writes, gc); | |
1620 | if (ret) | |
1621 | return ret; | |
cafe5635 KO |
1622 | } |
1623 | ||
a1f0358b KO |
1624 | bkey_copy_key(&b->c->gc_done, &b->key); |
1625 | ||
cafe5635 KO |
1626 | return ret; |
1627 | } | |
1628 | ||
1629 | static void btree_gc_start(struct cache_set *c) | |
1630 | { | |
1631 | struct cache *ca; | |
1632 | struct bucket *b; | |
cafe5635 KO |
1633 | unsigned i; |
1634 | ||
1635 | if (!c->gc_mark_valid) | |
1636 | return; | |
1637 | ||
1638 | mutex_lock(&c->bucket_lock); | |
1639 | ||
1640 | c->gc_mark_valid = 0; | |
1641 | c->gc_done = ZERO_KEY; | |
1642 | ||
1643 | for_each_cache(ca, c, i) | |
1644 | for_each_bucket(b, ca) { | |
3a2fd9d5 | 1645 | b->last_gc = b->gen; |
29ebf465 | 1646 | if (!atomic_read(&b->pin)) { |
4fe6a816 | 1647 | SET_GC_MARK(b, 0); |
29ebf465 KO |
1648 | SET_GC_SECTORS_USED(b, 0); |
1649 | } | |
cafe5635 KO |
1650 | } |
1651 | ||
cafe5635 KO |
1652 | mutex_unlock(&c->bucket_lock); |
1653 | } | |
1654 | ||
2531d9ee | 1655 | static size_t bch_btree_gc_finish(struct cache_set *c) |
cafe5635 KO |
1656 | { |
1657 | size_t available = 0; | |
1658 | struct bucket *b; | |
1659 | struct cache *ca; | |
cafe5635 KO |
1660 | unsigned i; |
1661 | ||
1662 | mutex_lock(&c->bucket_lock); | |
1663 | ||
1664 | set_gc_sectors(c); | |
1665 | c->gc_mark_valid = 1; | |
1666 | c->need_gc = 0; | |
1667 | ||
cafe5635 KO |
1668 | for (i = 0; i < KEY_PTRS(&c->uuid_bucket); i++) |
1669 | SET_GC_MARK(PTR_BUCKET(c, &c->uuid_bucket, i), | |
1670 | GC_MARK_METADATA); | |
1671 | ||
bf0a628a NS |
1672 | /* don't reclaim buckets to which writeback keys point */ |
1673 | rcu_read_lock(); | |
1674 | for (i = 0; i < c->nr_uuids; i++) { | |
1675 | struct bcache_device *d = c->devices[i]; | |
1676 | struct cached_dev *dc; | |
1677 | struct keybuf_key *w, *n; | |
1678 | unsigned j; | |
1679 | ||
1680 | if (!d || UUID_FLASH_ONLY(&c->uuids[i])) | |
1681 | continue; | |
1682 | dc = container_of(d, struct cached_dev, disk); | |
1683 | ||
1684 | spin_lock(&dc->writeback_keys.lock); | |
1685 | rbtree_postorder_for_each_entry_safe(w, n, | |
1686 | &dc->writeback_keys.keys, node) | |
1687 | for (j = 0; j < KEY_PTRS(&w->key); j++) | |
1688 | SET_GC_MARK(PTR_BUCKET(c, &w->key, j), | |
1689 | GC_MARK_DIRTY); | |
1690 | spin_unlock(&dc->writeback_keys.lock); | |
1691 | } | |
1692 | rcu_read_unlock(); | |
1693 | ||
cafe5635 KO |
1694 | for_each_cache(ca, c, i) { |
1695 | uint64_t *i; | |
1696 | ||
1697 | ca->invalidate_needs_gc = 0; | |
1698 | ||
1699 | for (i = ca->sb.d; i < ca->sb.d + ca->sb.keys; i++) | |
1700 | SET_GC_MARK(ca->buckets + *i, GC_MARK_METADATA); | |
1701 | ||
1702 | for (i = ca->prio_buckets; | |
1703 | i < ca->prio_buckets + prio_buckets(ca) * 2; i++) | |
1704 | SET_GC_MARK(ca->buckets + *i, GC_MARK_METADATA); | |
1705 | ||
1706 | for_each_bucket(b, ca) { | |
cafe5635 KO |
1707 | c->need_gc = max(c->need_gc, bucket_gc_gen(b)); |
1708 | ||
4fe6a816 KO |
1709 | if (atomic_read(&b->pin)) |
1710 | continue; | |
1711 | ||
1712 | BUG_ON(!GC_MARK(b) && GC_SECTORS_USED(b)); | |
1713 | ||
1714 | if (!GC_MARK(b) || GC_MARK(b) == GC_MARK_RECLAIMABLE) | |
cafe5635 | 1715 | available++; |
cafe5635 KO |
1716 | } |
1717 | } | |
1718 | ||
cafe5635 KO |
1719 | mutex_unlock(&c->bucket_lock); |
1720 | return available; | |
1721 | } | |
1722 | ||
72a44517 | 1723 | static void bch_btree_gc(struct cache_set *c) |
cafe5635 | 1724 | { |
cafe5635 KO |
1725 | int ret; |
1726 | unsigned long available; | |
1727 | struct gc_stat stats; | |
1728 | struct closure writes; | |
1729 | struct btree_op op; | |
cafe5635 | 1730 | uint64_t start_time = local_clock(); |
57943511 | 1731 | |
c37511b8 | 1732 | trace_bcache_gc_start(c); |
cafe5635 KO |
1733 | |
1734 | memset(&stats, 0, sizeof(struct gc_stat)); | |
1735 | closure_init_stack(&writes); | |
b54d6934 | 1736 | bch_btree_op_init(&op, SHRT_MAX); |
cafe5635 KO |
1737 | |
1738 | btree_gc_start(c); | |
1739 | ||
a1f0358b KO |
1740 | do { |
1741 | ret = btree_root(gc_root, c, &op, &writes, &stats); | |
1742 | closure_sync(&writes); | |
c5f1e5ad | 1743 | cond_resched(); |
cafe5635 | 1744 | |
a1f0358b KO |
1745 | if (ret && ret != -EAGAIN) |
1746 | pr_warn("gc failed!"); | |
1747 | } while (ret); | |
cafe5635 KO |
1748 | |
1749 | available = bch_btree_gc_finish(c); | |
57943511 KO |
1750 | wake_up_allocators(c); |
1751 | ||
169ef1cf | 1752 | bch_time_stats_update(&c->btree_gc_time, start_time); |
cafe5635 KO |
1753 | |
1754 | stats.key_bytes *= sizeof(uint64_t); | |
cafe5635 KO |
1755 | stats.data <<= 9; |
1756 | stats.in_use = (c->nbuckets - available) * 100 / c->nbuckets; | |
1757 | memcpy(&c->gc_stats, &stats, sizeof(struct gc_stat)); | |
cafe5635 | 1758 | |
c37511b8 | 1759 | trace_bcache_gc_end(c); |
cafe5635 | 1760 | |
72a44517 KO |
1761 | bch_moving_gc(c); |
1762 | } | |
1763 | ||
1764 | static int bch_gc_thread(void *arg) | |
1765 | { | |
1766 | struct cache_set *c = arg; | |
a1f0358b KO |
1767 | struct cache *ca; |
1768 | unsigned i; | |
72a44517 KO |
1769 | |
1770 | while (1) { | |
a1f0358b | 1771 | again: |
72a44517 KO |
1772 | bch_btree_gc(c); |
1773 | ||
1774 | set_current_state(TASK_INTERRUPTIBLE); | |
1775 | if (kthread_should_stop()) | |
1776 | break; | |
1777 | ||
a1f0358b KO |
1778 | mutex_lock(&c->bucket_lock); |
1779 | ||
1780 | for_each_cache(ca, c, i) | |
1781 | if (ca->invalidate_needs_gc) { | |
1782 | mutex_unlock(&c->bucket_lock); | |
1783 | set_current_state(TASK_RUNNING); | |
1784 | goto again; | |
1785 | } | |
1786 | ||
1787 | mutex_unlock(&c->bucket_lock); | |
1788 | ||
72a44517 KO |
1789 | schedule(); |
1790 | } | |
1791 | ||
1792 | return 0; | |
cafe5635 KO |
1793 | } |
1794 | ||
72a44517 | 1795 | int bch_gc_thread_start(struct cache_set *c) |
cafe5635 | 1796 | { |
72a44517 KO |
1797 | c->gc_thread = kthread_create(bch_gc_thread, c, "bcache_gc"); |
1798 | if (IS_ERR(c->gc_thread)) | |
1799 | return PTR_ERR(c->gc_thread); | |
1800 | ||
1801 | set_task_state(c->gc_thread, TASK_INTERRUPTIBLE); | |
1802 | return 0; | |
cafe5635 KO |
1803 | } |
1804 | ||
1805 | /* Initial partial gc */ | |
1806 | ||
487dded8 | 1807 | static int bch_btree_check_recurse(struct btree *b, struct btree_op *op) |
cafe5635 | 1808 | { |
50310164 | 1809 | int ret = 0; |
50310164 | 1810 | struct bkey *k, *p = NULL; |
cafe5635 KO |
1811 | struct btree_iter iter; |
1812 | ||
487dded8 KO |
1813 | for_each_key_filter(&b->keys, k, &iter, bch_ptr_invalid) |
1814 | bch_initial_mark_key(b->c, b->level, k); | |
cafe5635 | 1815 | |
487dded8 | 1816 | bch_initial_mark_key(b->c, b->level + 1, &b->key); |
cafe5635 KO |
1817 | |
1818 | if (b->level) { | |
c052dd9a | 1819 | bch_btree_iter_init(&b->keys, &iter, NULL); |
cafe5635 | 1820 | |
50310164 | 1821 | do { |
a85e968e KO |
1822 | k = bch_btree_iter_next_filter(&iter, &b->keys, |
1823 | bch_ptr_bad); | |
50310164 | 1824 | if (k) |
2452cc89 | 1825 | btree_node_prefetch(b, k); |
cafe5635 | 1826 | |
50310164 | 1827 | if (p) |
487dded8 | 1828 | ret = btree(check_recurse, p, b, op); |
cafe5635 | 1829 | |
50310164 KO |
1830 | p = k; |
1831 | } while (p && !ret); | |
cafe5635 KO |
1832 | } |
1833 | ||
487dded8 | 1834 | return ret; |
cafe5635 KO |
1835 | } |
1836 | ||
c18536a7 | 1837 | int bch_btree_check(struct cache_set *c) |
cafe5635 | 1838 | { |
c18536a7 | 1839 | struct btree_op op; |
cafe5635 | 1840 | |
b54d6934 | 1841 | bch_btree_op_init(&op, SHRT_MAX); |
cafe5635 | 1842 | |
487dded8 | 1843 | return btree_root(check_recurse, c, &op); |
cafe5635 KO |
1844 | } |
1845 | ||
2531d9ee KO |
1846 | void bch_initial_gc_finish(struct cache_set *c) |
1847 | { | |
1848 | struct cache *ca; | |
1849 | struct bucket *b; | |
1850 | unsigned i; | |
1851 | ||
1852 | bch_btree_gc_finish(c); | |
1853 | ||
1854 | mutex_lock(&c->bucket_lock); | |
1855 | ||
1856 | /* | |
1857 | * We need to put some unused buckets directly on the prio freelist in | |
1858 | * order to get the allocator thread started - it needs freed buckets in | |
1859 | * order to rewrite the prios and gens, and it needs to rewrite prios | |
1860 | * and gens in order to free buckets. | |
1861 | * | |
1862 | * This is only safe for buckets that have no live data in them, which | |
1863 | * there should always be some of. | |
1864 | */ | |
1865 | for_each_cache(ca, c, i) { | |
1866 | for_each_bucket(b, ca) { | |
1867 | if (fifo_full(&ca->free[RESERVE_PRIO])) | |
1868 | break; | |
1869 | ||
1870 | if (bch_can_invalidate_bucket(ca, b) && | |
1871 | !GC_MARK(b)) { | |
1872 | __bch_invalidate_one_bucket(ca, b); | |
1873 | fifo_push(&ca->free[RESERVE_PRIO], | |
1874 | b - ca->buckets); | |
1875 | } | |
1876 | } | |
1877 | } | |
1878 | ||
1879 | mutex_unlock(&c->bucket_lock); | |
1880 | } | |
1881 | ||
cafe5635 KO |
1882 | /* Btree insertion */ |
1883 | ||
829a60b9 KO |
1884 | static bool btree_insert_key(struct btree *b, struct bkey *k, |
1885 | struct bkey *replace_key) | |
cafe5635 | 1886 | { |
829a60b9 | 1887 | unsigned status; |
cafe5635 KO |
1888 | |
1889 | BUG_ON(bkey_cmp(k, &b->key) > 0); | |
1fa8455d | 1890 | |
829a60b9 KO |
1891 | status = bch_btree_insert_key(&b->keys, k, replace_key); |
1892 | if (status != BTREE_INSERT_STATUS_NO_INSERT) { | |
1893 | bch_check_keys(&b->keys, "%u for %s", status, | |
1894 | replace_key ? "replace" : "insert"); | |
cafe5635 | 1895 | |
829a60b9 KO |
1896 | trace_bcache_btree_insert_key(b, k, replace_key != NULL, |
1897 | status); | |
1898 | return true; | |
1899 | } else | |
1900 | return false; | |
cafe5635 KO |
1901 | } |
1902 | ||
59158fde KO |
1903 | static size_t insert_u64s_remaining(struct btree *b) |
1904 | { | |
3572324a | 1905 | long ret = bch_btree_keys_u64s_remaining(&b->keys); |
59158fde KO |
1906 | |
1907 | /* | |
1908 | * Might land in the middle of an existing extent and have to split it | |
1909 | */ | |
1910 | if (b->keys.ops->is_extents) | |
1911 | ret -= KEY_MAX_U64S; | |
1912 | ||
1913 | return max(ret, 0L); | |
1914 | } | |
1915 | ||
26c949f8 | 1916 | static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op, |
1b207d80 KO |
1917 | struct keylist *insert_keys, |
1918 | struct bkey *replace_key) | |
cafe5635 KO |
1919 | { |
1920 | bool ret = false; | |
dc9d98d6 | 1921 | int oldsize = bch_count_data(&b->keys); |
cafe5635 | 1922 | |
26c949f8 | 1923 | while (!bch_keylist_empty(insert_keys)) { |
c2f95ae2 | 1924 | struct bkey *k = insert_keys->keys; |
26c949f8 | 1925 | |
59158fde | 1926 | if (bkey_u64s(k) > insert_u64s_remaining(b)) |
403b6cde KO |
1927 | break; |
1928 | ||
1929 | if (bkey_cmp(k, &b->key) <= 0) { | |
3a3b6a4e KO |
1930 | if (!b->level) |
1931 | bkey_put(b->c, k); | |
26c949f8 | 1932 | |
829a60b9 | 1933 | ret |= btree_insert_key(b, k, replace_key); |
26c949f8 KO |
1934 | bch_keylist_pop_front(insert_keys); |
1935 | } else if (bkey_cmp(&START_KEY(k), &b->key) < 0) { | |
26c949f8 | 1936 | BKEY_PADDED(key) temp; |
c2f95ae2 | 1937 | bkey_copy(&temp.key, insert_keys->keys); |
26c949f8 KO |
1938 | |
1939 | bch_cut_back(&b->key, &temp.key); | |
c2f95ae2 | 1940 | bch_cut_front(&b->key, insert_keys->keys); |
26c949f8 | 1941 | |
829a60b9 | 1942 | ret |= btree_insert_key(b, &temp.key, replace_key); |
26c949f8 KO |
1943 | break; |
1944 | } else { | |
1945 | break; | |
1946 | } | |
cafe5635 KO |
1947 | } |
1948 | ||
829a60b9 KO |
1949 | if (!ret) |
1950 | op->insert_collision = true; | |
1951 | ||
403b6cde KO |
1952 | BUG_ON(!bch_keylist_empty(insert_keys) && b->level); |
1953 | ||
dc9d98d6 | 1954 | BUG_ON(bch_count_data(&b->keys) < oldsize); |
cafe5635 KO |
1955 | return ret; |
1956 | } | |
1957 | ||
26c949f8 KO |
1958 | static int btree_split(struct btree *b, struct btree_op *op, |
1959 | struct keylist *insert_keys, | |
1b207d80 | 1960 | struct bkey *replace_key) |
cafe5635 | 1961 | { |
d6fd3b11 | 1962 | bool split; |
cafe5635 KO |
1963 | struct btree *n1, *n2 = NULL, *n3 = NULL; |
1964 | uint64_t start_time = local_clock(); | |
b54d6934 | 1965 | struct closure cl; |
17e21a9f | 1966 | struct keylist parent_keys; |
b54d6934 KO |
1967 | |
1968 | closure_init_stack(&cl); | |
17e21a9f | 1969 | bch_keylist_init(&parent_keys); |
cafe5635 | 1970 | |
0a63b66d KO |
1971 | if (btree_check_reserve(b, op)) { |
1972 | if (!b->level) | |
1973 | return -EINTR; | |
1974 | else | |
1975 | WARN(1, "insufficient reserve for split\n"); | |
1976 | } | |
78365411 | 1977 | |
0a63b66d | 1978 | n1 = btree_node_alloc_replacement(b, op); |
cafe5635 KO |
1979 | if (IS_ERR(n1)) |
1980 | goto err; | |
1981 | ||
ee811287 KO |
1982 | split = set_blocks(btree_bset_first(n1), |
1983 | block_bytes(n1->c)) > (btree_blocks(b) * 4) / 5; | |
cafe5635 | 1984 | |
cafe5635 KO |
1985 | if (split) { |
1986 | unsigned keys = 0; | |
1987 | ||
ee811287 | 1988 | trace_bcache_btree_node_split(b, btree_bset_first(n1)->keys); |
c37511b8 | 1989 | |
2452cc89 | 1990 | n2 = bch_btree_node_alloc(b->c, op, b->level, b->parent); |
cafe5635 KO |
1991 | if (IS_ERR(n2)) |
1992 | goto err_free1; | |
1993 | ||
d6fd3b11 | 1994 | if (!b->parent) { |
2452cc89 | 1995 | n3 = bch_btree_node_alloc(b->c, op, b->level + 1, NULL); |
cafe5635 KO |
1996 | if (IS_ERR(n3)) |
1997 | goto err_free2; | |
1998 | } | |
1999 | ||
2a285686 KO |
2000 | mutex_lock(&n1->write_lock); |
2001 | mutex_lock(&n2->write_lock); | |
2002 | ||
1b207d80 | 2003 | bch_btree_insert_keys(n1, op, insert_keys, replace_key); |
cafe5635 | 2004 | |
d6fd3b11 KO |
2005 | /* |
2006 | * Has to be a linear search because we don't have an auxiliary | |
cafe5635 KO |
2007 | * search tree yet |
2008 | */ | |
2009 | ||
ee811287 KO |
2010 | while (keys < (btree_bset_first(n1)->keys * 3) / 5) |
2011 | keys += bkey_u64s(bset_bkey_idx(btree_bset_first(n1), | |
fafff81c | 2012 | keys)); |
cafe5635 | 2013 | |
fafff81c | 2014 | bkey_copy_key(&n1->key, |
ee811287 KO |
2015 | bset_bkey_idx(btree_bset_first(n1), keys)); |
2016 | keys += bkey_u64s(bset_bkey_idx(btree_bset_first(n1), keys)); | |
cafe5635 | 2017 | |
ee811287 KO |
2018 | btree_bset_first(n2)->keys = btree_bset_first(n1)->keys - keys; |
2019 | btree_bset_first(n1)->keys = keys; | |
cafe5635 | 2020 | |
ee811287 KO |
2021 | memcpy(btree_bset_first(n2)->start, |
2022 | bset_bkey_last(btree_bset_first(n1)), | |
2023 | btree_bset_first(n2)->keys * sizeof(uint64_t)); | |
cafe5635 KO |
2024 | |
2025 | bkey_copy_key(&n2->key, &b->key); | |
2026 | ||
17e21a9f | 2027 | bch_keylist_add(&parent_keys, &n2->key); |
b54d6934 | 2028 | bch_btree_node_write(n2, &cl); |
2a285686 | 2029 | mutex_unlock(&n2->write_lock); |
cafe5635 | 2030 | rw_unlock(true, n2); |
c37511b8 | 2031 | } else { |
ee811287 | 2032 | trace_bcache_btree_node_compact(b, btree_bset_first(n1)->keys); |
c37511b8 | 2033 | |
2a285686 | 2034 | mutex_lock(&n1->write_lock); |
1b207d80 | 2035 | bch_btree_insert_keys(n1, op, insert_keys, replace_key); |
c37511b8 | 2036 | } |
cafe5635 | 2037 | |
17e21a9f | 2038 | bch_keylist_add(&parent_keys, &n1->key); |
b54d6934 | 2039 | bch_btree_node_write(n1, &cl); |
2a285686 | 2040 | mutex_unlock(&n1->write_lock); |
cafe5635 KO |
2041 | |
2042 | if (n3) { | |
d6fd3b11 | 2043 | /* Depth increases, make a new root */ |
2a285686 | 2044 | mutex_lock(&n3->write_lock); |
cafe5635 | 2045 | bkey_copy_key(&n3->key, &MAX_KEY); |
17e21a9f | 2046 | bch_btree_insert_keys(n3, op, &parent_keys, NULL); |
b54d6934 | 2047 | bch_btree_node_write(n3, &cl); |
2a285686 | 2048 | mutex_unlock(&n3->write_lock); |
cafe5635 | 2049 | |
b54d6934 | 2050 | closure_sync(&cl); |
cafe5635 KO |
2051 | bch_btree_set_root(n3); |
2052 | rw_unlock(true, n3); | |
d6fd3b11 KO |
2053 | } else if (!b->parent) { |
2054 | /* Root filled up but didn't need to be split */ | |
b54d6934 | 2055 | closure_sync(&cl); |
cafe5635 KO |
2056 | bch_btree_set_root(n1); |
2057 | } else { | |
17e21a9f | 2058 | /* Split a non root node */ |
b54d6934 | 2059 | closure_sync(&cl); |
17e21a9f KO |
2060 | make_btree_freeing_key(b, parent_keys.top); |
2061 | bch_keylist_push(&parent_keys); | |
2062 | ||
17e21a9f KO |
2063 | bch_btree_insert_node(b->parent, op, &parent_keys, NULL, NULL); |
2064 | BUG_ON(!bch_keylist_empty(&parent_keys)); | |
cafe5635 KO |
2065 | } |
2066 | ||
05335cff | 2067 | btree_node_free(b); |
cafe5635 | 2068 | rw_unlock(true, n1); |
cafe5635 | 2069 | |
169ef1cf | 2070 | bch_time_stats_update(&b->c->btree_split_time, start_time); |
cafe5635 KO |
2071 | |
2072 | return 0; | |
2073 | err_free2: | |
5f5837d2 | 2074 | bkey_put(b->c, &n2->key); |
e8e1d468 | 2075 | btree_node_free(n2); |
cafe5635 KO |
2076 | rw_unlock(true, n2); |
2077 | err_free1: | |
5f5837d2 | 2078 | bkey_put(b->c, &n1->key); |
e8e1d468 | 2079 | btree_node_free(n1); |
cafe5635 KO |
2080 | rw_unlock(true, n1); |
2081 | err: | |
0a63b66d | 2082 | WARN(1, "bcache: btree split failed (level %u)", b->level); |
5f5837d2 | 2083 | |
cafe5635 KO |
2084 | if (n3 == ERR_PTR(-EAGAIN) || |
2085 | n2 == ERR_PTR(-EAGAIN) || | |
2086 | n1 == ERR_PTR(-EAGAIN)) | |
2087 | return -EAGAIN; | |
2088 | ||
cafe5635 KO |
2089 | return -ENOMEM; |
2090 | } | |
2091 | ||
26c949f8 | 2092 | static int bch_btree_insert_node(struct btree *b, struct btree_op *op, |
c18536a7 | 2093 | struct keylist *insert_keys, |
1b207d80 KO |
2094 | atomic_t *journal_ref, |
2095 | struct bkey *replace_key) | |
cafe5635 | 2096 | { |
2a285686 KO |
2097 | struct closure cl; |
2098 | ||
17e21a9f KO |
2099 | BUG_ON(b->level && replace_key); |
2100 | ||
2a285686 KO |
2101 | closure_init_stack(&cl); |
2102 | ||
2103 | mutex_lock(&b->write_lock); | |
2104 | ||
2105 | if (write_block(b) != btree_bset_last(b) && | |
2106 | b->keys.last_set_unwritten) | |
2107 | bch_btree_init_next(b); /* just wrote a set */ | |
2108 | ||
59158fde | 2109 | if (bch_keylist_nkeys(insert_keys) > insert_u64s_remaining(b)) { |
2a285686 KO |
2110 | mutex_unlock(&b->write_lock); |
2111 | goto split; | |
2112 | } | |
3b3e9e50 | 2113 | |
2a285686 | 2114 | BUG_ON(write_block(b) != btree_bset_last(b)); |
cafe5635 | 2115 | |
2a285686 KO |
2116 | if (bch_btree_insert_keys(b, op, insert_keys, replace_key)) { |
2117 | if (!b->level) | |
2118 | bch_btree_leaf_dirty(b, journal_ref); | |
2119 | else | |
2120 | bch_btree_node_write(b, &cl); | |
2121 | } | |
17e21a9f | 2122 | |
2a285686 KO |
2123 | mutex_unlock(&b->write_lock); |
2124 | ||
2125 | /* wait for btree node write if necessary, after unlock */ | |
2126 | closure_sync(&cl); | |
2127 | ||
2128 | return 0; | |
2129 | split: | |
2130 | if (current->bio_list) { | |
2131 | op->lock = b->c->root->level + 1; | |
2132 | return -EAGAIN; | |
2133 | } else if (op->lock <= b->c->root->level) { | |
2134 | op->lock = b->c->root->level + 1; | |
2135 | return -EINTR; | |
2136 | } else { | |
2137 | /* Invalidated all iterators */ | |
2138 | int ret = btree_split(b, op, insert_keys, replace_key); | |
2139 | ||
2140 | if (bch_keylist_empty(insert_keys)) | |
2141 | return 0; | |
2142 | else if (!ret) | |
2143 | return -EINTR; | |
2144 | return ret; | |
17e21a9f | 2145 | } |
26c949f8 | 2146 | } |
cafe5635 | 2147 | |
e7c590eb KO |
2148 | int bch_btree_insert_check_key(struct btree *b, struct btree_op *op, |
2149 | struct bkey *check_key) | |
2150 | { | |
2151 | int ret = -EINTR; | |
2152 | uint64_t btree_ptr = b->key.ptr[0]; | |
2153 | unsigned long seq = b->seq; | |
2154 | struct keylist insert; | |
2155 | bool upgrade = op->lock == -1; | |
2156 | ||
2157 | bch_keylist_init(&insert); | |
2158 | ||
2159 | if (upgrade) { | |
2160 | rw_unlock(false, b); | |
2161 | rw_lock(true, b, b->level); | |
2162 | ||
2163 | if (b->key.ptr[0] != btree_ptr || | |
2ef9ccbf ZL |
2164 | b->seq != seq + 1) { |
2165 | op->lock = b->level; | |
e7c590eb | 2166 | goto out; |
2ef9ccbf | 2167 | } |
e7c590eb KO |
2168 | } |
2169 | ||
2170 | SET_KEY_PTRS(check_key, 1); | |
2171 | get_random_bytes(&check_key->ptr[0], sizeof(uint64_t)); | |
2172 | ||
2173 | SET_PTR_DEV(check_key, 0, PTR_CHECK_DEV); | |
2174 | ||
2175 | bch_keylist_add(&insert, check_key); | |
2176 | ||
1b207d80 | 2177 | ret = bch_btree_insert_node(b, op, &insert, NULL, NULL); |
e7c590eb KO |
2178 | |
2179 | BUG_ON(!ret && !bch_keylist_empty(&insert)); | |
2180 | out: | |
2181 | if (upgrade) | |
2182 | downgrade_write(&b->lock); | |
2183 | return ret; | |
2184 | } | |
2185 | ||
cc7b8819 KO |
2186 | struct btree_insert_op { |
2187 | struct btree_op op; | |
2188 | struct keylist *keys; | |
2189 | atomic_t *journal_ref; | |
2190 | struct bkey *replace_key; | |
2191 | }; | |
cafe5635 | 2192 | |
08239ca2 | 2193 | static int btree_insert_fn(struct btree_op *b_op, struct btree *b) |
cc7b8819 KO |
2194 | { |
2195 | struct btree_insert_op *op = container_of(b_op, | |
2196 | struct btree_insert_op, op); | |
cafe5635 | 2197 | |
cc7b8819 KO |
2198 | int ret = bch_btree_insert_node(b, &op->op, op->keys, |
2199 | op->journal_ref, op->replace_key); | |
2200 | if (ret && !bch_keylist_empty(op->keys)) | |
2201 | return ret; | |
2202 | else | |
2203 | return MAP_DONE; | |
cafe5635 KO |
2204 | } |
2205 | ||
cc7b8819 KO |
2206 | int bch_btree_insert(struct cache_set *c, struct keylist *keys, |
2207 | atomic_t *journal_ref, struct bkey *replace_key) | |
cafe5635 | 2208 | { |
cc7b8819 | 2209 | struct btree_insert_op op; |
cafe5635 | 2210 | int ret = 0; |
cafe5635 | 2211 | |
cc7b8819 | 2212 | BUG_ON(current->bio_list); |
4f3d4014 | 2213 | BUG_ON(bch_keylist_empty(keys)); |
cafe5635 | 2214 | |
cc7b8819 KO |
2215 | bch_btree_op_init(&op.op, 0); |
2216 | op.keys = keys; | |
2217 | op.journal_ref = journal_ref; | |
2218 | op.replace_key = replace_key; | |
cafe5635 | 2219 | |
cc7b8819 KO |
2220 | while (!ret && !bch_keylist_empty(keys)) { |
2221 | op.op.lock = 0; | |
2222 | ret = bch_btree_map_leaf_nodes(&op.op, c, | |
2223 | &START_KEY(keys->keys), | |
2224 | btree_insert_fn); | |
2225 | } | |
cafe5635 | 2226 | |
cc7b8819 KO |
2227 | if (ret) { |
2228 | struct bkey *k; | |
cafe5635 | 2229 | |
cc7b8819 | 2230 | pr_err("error %i", ret); |
cafe5635 | 2231 | |
cc7b8819 | 2232 | while ((k = bch_keylist_pop(keys))) |
3a3b6a4e | 2233 | bkey_put(c, k); |
cc7b8819 KO |
2234 | } else if (op.op.insert_collision) |
2235 | ret = -ESRCH; | |
6054c6d4 | 2236 | |
cafe5635 KO |
2237 | return ret; |
2238 | } | |
2239 | ||
2240 | void bch_btree_set_root(struct btree *b) | |
2241 | { | |
2242 | unsigned i; | |
e49c7c37 KO |
2243 | struct closure cl; |
2244 | ||
2245 | closure_init_stack(&cl); | |
cafe5635 | 2246 | |
c37511b8 KO |
2247 | trace_bcache_btree_set_root(b); |
2248 | ||
cafe5635 KO |
2249 | BUG_ON(!b->written); |
2250 | ||
2251 | for (i = 0; i < KEY_PTRS(&b->key); i++) | |
2252 | BUG_ON(PTR_BUCKET(b->c, &b->key, i)->prio != BTREE_PRIO); | |
2253 | ||
2254 | mutex_lock(&b->c->bucket_lock); | |
2255 | list_del_init(&b->list); | |
2256 | mutex_unlock(&b->c->bucket_lock); | |
2257 | ||
2258 | b->c->root = b; | |
cafe5635 | 2259 | |
e49c7c37 KO |
2260 | bch_journal_meta(b->c, &cl); |
2261 | closure_sync(&cl); | |
cafe5635 KO |
2262 | } |
2263 | ||
48dad8ba KO |
2264 | /* Map across nodes or keys */ |
2265 | ||
2266 | static int bch_btree_map_nodes_recurse(struct btree *b, struct btree_op *op, | |
2267 | struct bkey *from, | |
2268 | btree_map_nodes_fn *fn, int flags) | |
2269 | { | |
2270 | int ret = MAP_CONTINUE; | |
2271 | ||
2272 | if (b->level) { | |
2273 | struct bkey *k; | |
2274 | struct btree_iter iter; | |
2275 | ||
c052dd9a | 2276 | bch_btree_iter_init(&b->keys, &iter, from); |
48dad8ba | 2277 | |
a85e968e | 2278 | while ((k = bch_btree_iter_next_filter(&iter, &b->keys, |
48dad8ba KO |
2279 | bch_ptr_bad))) { |
2280 | ret = btree(map_nodes_recurse, k, b, | |
2281 | op, from, fn, flags); | |
2282 | from = NULL; | |
2283 | ||
2284 | if (ret != MAP_CONTINUE) | |
2285 | return ret; | |
2286 | } | |
2287 | } | |
2288 | ||
2289 | if (!b->level || flags == MAP_ALL_NODES) | |
2290 | ret = fn(op, b); | |
2291 | ||
2292 | return ret; | |
2293 | } | |
2294 | ||
2295 | int __bch_btree_map_nodes(struct btree_op *op, struct cache_set *c, | |
2296 | struct bkey *from, btree_map_nodes_fn *fn, int flags) | |
2297 | { | |
b54d6934 | 2298 | return btree_root(map_nodes_recurse, c, op, from, fn, flags); |
48dad8ba KO |
2299 | } |
2300 | ||
2301 | static int bch_btree_map_keys_recurse(struct btree *b, struct btree_op *op, | |
2302 | struct bkey *from, btree_map_keys_fn *fn, | |
2303 | int flags) | |
2304 | { | |
2305 | int ret = MAP_CONTINUE; | |
2306 | struct bkey *k; | |
2307 | struct btree_iter iter; | |
2308 | ||
c052dd9a | 2309 | bch_btree_iter_init(&b->keys, &iter, from); |
48dad8ba | 2310 | |
a85e968e | 2311 | while ((k = bch_btree_iter_next_filter(&iter, &b->keys, bch_ptr_bad))) { |
48dad8ba KO |
2312 | ret = !b->level |
2313 | ? fn(op, b, k) | |
2314 | : btree(map_keys_recurse, k, b, op, from, fn, flags); | |
2315 | from = NULL; | |
2316 | ||
2317 | if (ret != MAP_CONTINUE) | |
2318 | return ret; | |
2319 | } | |
2320 | ||
2321 | if (!b->level && (flags & MAP_END_KEY)) | |
2322 | ret = fn(op, b, &KEY(KEY_INODE(&b->key), | |
2323 | KEY_OFFSET(&b->key), 0)); | |
2324 | ||
2325 | return ret; | |
2326 | } | |
2327 | ||
2328 | int bch_btree_map_keys(struct btree_op *op, struct cache_set *c, | |
2329 | struct bkey *from, btree_map_keys_fn *fn, int flags) | |
2330 | { | |
b54d6934 | 2331 | return btree_root(map_keys_recurse, c, op, from, fn, flags); |
48dad8ba KO |
2332 | } |
2333 | ||
cafe5635 KO |
2334 | /* Keybuf code */ |
2335 | ||
2336 | static inline int keybuf_cmp(struct keybuf_key *l, struct keybuf_key *r) | |
2337 | { | |
2338 | /* Overlapping keys compare equal */ | |
2339 | if (bkey_cmp(&l->key, &START_KEY(&r->key)) <= 0) | |
2340 | return -1; | |
2341 | if (bkey_cmp(&START_KEY(&l->key), &r->key) >= 0) | |
2342 | return 1; | |
2343 | return 0; | |
2344 | } | |
2345 | ||
2346 | static inline int keybuf_nonoverlapping_cmp(struct keybuf_key *l, | |
2347 | struct keybuf_key *r) | |
2348 | { | |
2349 | return clamp_t(int64_t, bkey_cmp(&l->key, &r->key), -1, 1); | |
2350 | } | |
2351 | ||
48dad8ba KO |
2352 | struct refill { |
2353 | struct btree_op op; | |
48a915a8 | 2354 | unsigned nr_found; |
48dad8ba KO |
2355 | struct keybuf *buf; |
2356 | struct bkey *end; | |
2357 | keybuf_pred_fn *pred; | |
2358 | }; | |
cafe5635 | 2359 | |
48dad8ba KO |
2360 | static int refill_keybuf_fn(struct btree_op *op, struct btree *b, |
2361 | struct bkey *k) | |
2362 | { | |
2363 | struct refill *refill = container_of(op, struct refill, op); | |
2364 | struct keybuf *buf = refill->buf; | |
2365 | int ret = MAP_CONTINUE; | |
cafe5635 | 2366 | |
48dad8ba KO |
2367 | if (bkey_cmp(k, refill->end) >= 0) { |
2368 | ret = MAP_DONE; | |
2369 | goto out; | |
2370 | } | |
cafe5635 | 2371 | |
48dad8ba KO |
2372 | if (!KEY_SIZE(k)) /* end key */ |
2373 | goto out; | |
cafe5635 | 2374 | |
48dad8ba KO |
2375 | if (refill->pred(buf, k)) { |
2376 | struct keybuf_key *w; | |
cafe5635 | 2377 | |
48dad8ba | 2378 | spin_lock(&buf->lock); |
cafe5635 | 2379 | |
48dad8ba KO |
2380 | w = array_alloc(&buf->freelist); |
2381 | if (!w) { | |
2382 | spin_unlock(&buf->lock); | |
2383 | return MAP_DONE; | |
2384 | } | |
cafe5635 | 2385 | |
48dad8ba KO |
2386 | w->private = NULL; |
2387 | bkey_copy(&w->key, k); | |
cafe5635 | 2388 | |
48dad8ba KO |
2389 | if (RB_INSERT(&buf->keys, w, node, keybuf_cmp)) |
2390 | array_free(&buf->freelist, w); | |
48a915a8 KO |
2391 | else |
2392 | refill->nr_found++; | |
cafe5635 | 2393 | |
48dad8ba KO |
2394 | if (array_freelist_empty(&buf->freelist)) |
2395 | ret = MAP_DONE; | |
cafe5635 | 2396 | |
48dad8ba | 2397 | spin_unlock(&buf->lock); |
cafe5635 | 2398 | } |
48dad8ba KO |
2399 | out: |
2400 | buf->last_scanned = *k; | |
2401 | return ret; | |
cafe5635 KO |
2402 | } |
2403 | ||
2404 | void bch_refill_keybuf(struct cache_set *c, struct keybuf *buf, | |
72c27061 | 2405 | struct bkey *end, keybuf_pred_fn *pred) |
cafe5635 KO |
2406 | { |
2407 | struct bkey start = buf->last_scanned; | |
48dad8ba | 2408 | struct refill refill; |
cafe5635 KO |
2409 | |
2410 | cond_resched(); | |
2411 | ||
b54d6934 | 2412 | bch_btree_op_init(&refill.op, -1); |
48a915a8 KO |
2413 | refill.nr_found = 0; |
2414 | refill.buf = buf; | |
2415 | refill.end = end; | |
2416 | refill.pred = pred; | |
48dad8ba KO |
2417 | |
2418 | bch_btree_map_keys(&refill.op, c, &buf->last_scanned, | |
2419 | refill_keybuf_fn, MAP_END_KEY); | |
cafe5635 | 2420 | |
48a915a8 KO |
2421 | trace_bcache_keyscan(refill.nr_found, |
2422 | KEY_INODE(&start), KEY_OFFSET(&start), | |
2423 | KEY_INODE(&buf->last_scanned), | |
2424 | KEY_OFFSET(&buf->last_scanned)); | |
cafe5635 KO |
2425 | |
2426 | spin_lock(&buf->lock); | |
2427 | ||
2428 | if (!RB_EMPTY_ROOT(&buf->keys)) { | |
2429 | struct keybuf_key *w; | |
2430 | w = RB_FIRST(&buf->keys, struct keybuf_key, node); | |
2431 | buf->start = START_KEY(&w->key); | |
2432 | ||
2433 | w = RB_LAST(&buf->keys, struct keybuf_key, node); | |
2434 | buf->end = w->key; | |
2435 | } else { | |
2436 | buf->start = MAX_KEY; | |
2437 | buf->end = MAX_KEY; | |
2438 | } | |
2439 | ||
2440 | spin_unlock(&buf->lock); | |
2441 | } | |
2442 | ||
2443 | static void __bch_keybuf_del(struct keybuf *buf, struct keybuf_key *w) | |
2444 | { | |
2445 | rb_erase(&w->node, &buf->keys); | |
2446 | array_free(&buf->freelist, w); | |
2447 | } | |
2448 | ||
2449 | void bch_keybuf_del(struct keybuf *buf, struct keybuf_key *w) | |
2450 | { | |
2451 | spin_lock(&buf->lock); | |
2452 | __bch_keybuf_del(buf, w); | |
2453 | spin_unlock(&buf->lock); | |
2454 | } | |
2455 | ||
2456 | bool bch_keybuf_check_overlapping(struct keybuf *buf, struct bkey *start, | |
2457 | struct bkey *end) | |
2458 | { | |
2459 | bool ret = false; | |
2460 | struct keybuf_key *p, *w, s; | |
2461 | s.key = *start; | |
2462 | ||
2463 | if (bkey_cmp(end, &buf->start) <= 0 || | |
2464 | bkey_cmp(start, &buf->end) >= 0) | |
2465 | return false; | |
2466 | ||
2467 | spin_lock(&buf->lock); | |
2468 | w = RB_GREATER(&buf->keys, s, node, keybuf_nonoverlapping_cmp); | |
2469 | ||
2470 | while (w && bkey_cmp(&START_KEY(&w->key), end) < 0) { | |
2471 | p = w; | |
2472 | w = RB_NEXT(w, node); | |
2473 | ||
2474 | if (p->private) | |
2475 | ret = true; | |
2476 | else | |
2477 | __bch_keybuf_del(buf, p); | |
2478 | } | |
2479 | ||
2480 | spin_unlock(&buf->lock); | |
2481 | return ret; | |
2482 | } | |
2483 | ||
2484 | struct keybuf_key *bch_keybuf_next(struct keybuf *buf) | |
2485 | { | |
2486 | struct keybuf_key *w; | |
2487 | spin_lock(&buf->lock); | |
2488 | ||
2489 | w = RB_FIRST(&buf->keys, struct keybuf_key, node); | |
2490 | ||
2491 | while (w && w->private) | |
2492 | w = RB_NEXT(w, node); | |
2493 | ||
2494 | if (w) | |
2495 | w->private = ERR_PTR(-EINTR); | |
2496 | ||
2497 | spin_unlock(&buf->lock); | |
2498 | return w; | |
2499 | } | |
2500 | ||
2501 | struct keybuf_key *bch_keybuf_next_rescan(struct cache_set *c, | |
48dad8ba KO |
2502 | struct keybuf *buf, |
2503 | struct bkey *end, | |
2504 | keybuf_pred_fn *pred) | |
cafe5635 KO |
2505 | { |
2506 | struct keybuf_key *ret; | |
2507 | ||
2508 | while (1) { | |
2509 | ret = bch_keybuf_next(buf); | |
2510 | if (ret) | |
2511 | break; | |
2512 | ||
2513 | if (bkey_cmp(&buf->last_scanned, end) >= 0) { | |
2514 | pr_debug("scan finished"); | |
2515 | break; | |
2516 | } | |
2517 | ||
72c27061 | 2518 | bch_refill_keybuf(c, buf, end, pred); |
cafe5635 KO |
2519 | } |
2520 | ||
2521 | return ret; | |
2522 | } | |
2523 | ||
72c27061 | 2524 | void bch_keybuf_init(struct keybuf *buf) |
cafe5635 | 2525 | { |
cafe5635 KO |
2526 | buf->last_scanned = MAX_KEY; |
2527 | buf->keys = RB_ROOT; | |
2528 | ||
2529 | spin_lock_init(&buf->lock); | |
2530 | array_allocator_init(&buf->freelist); | |
2531 | } |