Merge tag 'icc-6.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc...
[linux-2.6-microblaze.git] / drivers / md / bcache / movinggc.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Moving/copying garbage collector
4  *
5  * Copyright 2012 Google, Inc.
6  */
7
8 #include "bcache.h"
9 #include "btree.h"
10 #include "debug.h"
11 #include "request.h"
12
13 #include <trace/events/bcache.h>
14
15 struct moving_io {
16         struct closure          cl;
17         struct keybuf_key       *w;
18         struct data_insert_op   op;
19         struct bbio             bio;
20 };
21
22 static bool moving_pred(struct keybuf *buf, struct bkey *k)
23 {
24         struct cache_set *c = container_of(buf, struct cache_set,
25                                            moving_gc_keys);
26         unsigned int i;
27
28         for (i = 0; i < KEY_PTRS(k); i++)
29                 if (ptr_available(c, k, i) &&
30                     GC_MOVE(PTR_BUCKET(c, k, i)))
31                         return true;
32
33         return false;
34 }
35
36 /* Moving GC - IO loop */
37
38 static CLOSURE_CALLBACK(moving_io_destructor)
39 {
40         closure_type(io, struct moving_io, cl);
41
42         kfree(io);
43 }
44
45 static CLOSURE_CALLBACK(write_moving_finish)
46 {
47         closure_type(io, struct moving_io, cl);
48         struct bio *bio = &io->bio.bio;
49
50         bio_free_pages(bio);
51
52         if (io->op.replace_collision)
53                 trace_bcache_gc_copy_collision(&io->w->key);
54
55         bch_keybuf_del(&io->op.c->moving_gc_keys, io->w);
56
57         up(&io->op.c->moving_in_flight);
58
59         closure_return_with_destructor(cl, moving_io_destructor);
60 }
61
62 static void read_moving_endio(struct bio *bio)
63 {
64         struct bbio *b = container_of(bio, struct bbio, bio);
65         struct moving_io *io = container_of(bio->bi_private,
66                                             struct moving_io, cl);
67
68         if (bio->bi_status)
69                 io->op.status = bio->bi_status;
70         else if (!KEY_DIRTY(&b->key) &&
71                  ptr_stale(io->op.c, &b->key, 0)) {
72                 io->op.status = BLK_STS_IOERR;
73         }
74
75         bch_bbio_endio(io->op.c, bio, bio->bi_status, "reading data to move");
76 }
77
78 static void moving_init(struct moving_io *io)
79 {
80         struct bio *bio = &io->bio.bio;
81
82         bio_init(bio, NULL, bio->bi_inline_vecs,
83                  DIV_ROUND_UP(KEY_SIZE(&io->w->key), PAGE_SECTORS), 0);
84         bio_get(bio);
85         bio_set_prio(bio, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0));
86
87         bio->bi_iter.bi_size    = KEY_SIZE(&io->w->key) << 9;
88         bio->bi_private         = &io->cl;
89         bch_bio_map(bio, NULL);
90 }
91
92 static CLOSURE_CALLBACK(write_moving)
93 {
94         closure_type(io, struct moving_io, cl);
95         struct data_insert_op *op = &io->op;
96
97         if (!op->status) {
98                 moving_init(io);
99
100                 io->bio.bio.bi_iter.bi_sector = KEY_START(&io->w->key);
101                 op->write_prio          = 1;
102                 op->bio                 = &io->bio.bio;
103
104                 op->writeback           = KEY_DIRTY(&io->w->key);
105                 op->csum                = KEY_CSUM(&io->w->key);
106
107                 bkey_copy(&op->replace_key, &io->w->key);
108                 op->replace             = true;
109
110                 closure_call(&op->cl, bch_data_insert, NULL, cl);
111         }
112
113         continue_at(cl, write_moving_finish, op->wq);
114 }
115
116 static CLOSURE_CALLBACK(read_moving_submit)
117 {
118         closure_type(io, struct moving_io, cl);
119         struct bio *bio = &io->bio.bio;
120
121         bch_submit_bbio(bio, io->op.c, &io->w->key, 0);
122
123         continue_at(cl, write_moving, io->op.wq);
124 }
125
126 static void read_moving(struct cache_set *c)
127 {
128         struct keybuf_key *w;
129         struct moving_io *io;
130         struct bio *bio;
131         struct closure cl;
132
133         closure_init_stack(&cl);
134
135         /* XXX: if we error, background writeback could stall indefinitely */
136
137         while (!test_bit(CACHE_SET_STOPPING, &c->flags)) {
138                 w = bch_keybuf_next_rescan(c, &c->moving_gc_keys,
139                                            &MAX_KEY, moving_pred);
140                 if (!w)
141                         break;
142
143                 if (ptr_stale(c, &w->key, 0)) {
144                         bch_keybuf_del(&c->moving_gc_keys, w);
145                         continue;
146                 }
147
148                 io = kzalloc(struct_size(io, bio.bio.bi_inline_vecs,
149                                          DIV_ROUND_UP(KEY_SIZE(&w->key), PAGE_SECTORS)),
150                              GFP_KERNEL);
151                 if (!io)
152                         goto err;
153
154                 w->private      = io;
155                 io->w           = w;
156                 io->op.inode    = KEY_INODE(&w->key);
157                 io->op.c        = c;
158                 io->op.wq       = c->moving_gc_wq;
159
160                 moving_init(io);
161                 bio = &io->bio.bio;
162
163                 bio->bi_opf = REQ_OP_READ;
164                 bio->bi_end_io  = read_moving_endio;
165
166                 if (bch_bio_alloc_pages(bio, GFP_KERNEL))
167                         goto err;
168
169                 trace_bcache_gc_copy(&w->key);
170
171                 down(&c->moving_in_flight);
172                 closure_call(&io->cl, read_moving_submit, NULL, &cl);
173         }
174
175         if (0) {
176 err:            if (!IS_ERR_OR_NULL(w->private))
177                         kfree(w->private);
178
179                 bch_keybuf_del(&c->moving_gc_keys, w);
180         }
181
182         closure_sync(&cl);
183 }
184
185 static bool bucket_cmp(struct bucket *l, struct bucket *r)
186 {
187         return GC_SECTORS_USED(l) < GC_SECTORS_USED(r);
188 }
189
190 static unsigned int bucket_heap_top(struct cache *ca)
191 {
192         struct bucket *b;
193
194         return (b = heap_peek(&ca->heap)) ? GC_SECTORS_USED(b) : 0;
195 }
196
197 void bch_moving_gc(struct cache_set *c)
198 {
199         struct cache *ca = c->cache;
200         struct bucket *b;
201         unsigned long sectors_to_move, reserve_sectors;
202
203         if (!c->copy_gc_enabled)
204                 return;
205
206         mutex_lock(&c->bucket_lock);
207
208         sectors_to_move = 0;
209         reserve_sectors = ca->sb.bucket_size *
210                              fifo_used(&ca->free[RESERVE_MOVINGGC]);
211
212         ca->heap.used = 0;
213
214         for_each_bucket(b, ca) {
215                 if (GC_MARK(b) == GC_MARK_METADATA ||
216                     !GC_SECTORS_USED(b) ||
217                     GC_SECTORS_USED(b) == ca->sb.bucket_size ||
218                     atomic_read(&b->pin))
219                         continue;
220
221                 if (!heap_full(&ca->heap)) {
222                         sectors_to_move += GC_SECTORS_USED(b);
223                         heap_add(&ca->heap, b, bucket_cmp);
224                 } else if (bucket_cmp(b, heap_peek(&ca->heap))) {
225                         sectors_to_move -= bucket_heap_top(ca);
226                         sectors_to_move += GC_SECTORS_USED(b);
227
228                         ca->heap.data[0] = b;
229                         heap_sift(&ca->heap, 0, bucket_cmp);
230                 }
231         }
232
233         while (sectors_to_move > reserve_sectors) {
234                 heap_pop(&ca->heap, b, bucket_cmp);
235                 sectors_to_move -= GC_SECTORS_USED(b);
236         }
237
238         while (heap_pop(&ca->heap, b, bucket_cmp))
239                 SET_GC_MOVE(b, 1);
240
241         mutex_unlock(&c->bucket_lock);
242
243         c->moving_gc_keys.last_scanned = ZERO_KEY;
244
245         read_moving(c);
246 }
247
248 void bch_moving_init_cache_set(struct cache_set *c)
249 {
250         bch_keybuf_init(&c->moving_gc_keys);
251         sema_init(&c->moving_in_flight, 64);
252 }