| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 1 | #ifndef _BCACHE_WRITEBACK_H |
| 2 | #define _BCACHE_WRITEBACK_H |
| 3 | |
| 4 | #define CUTOFF_WRITEBACK 40 |
| 5 | #define CUTOFF_WRITEBACK_SYNC 70 |
| 6 | |
| 7 | static inline uint64_t bcache_dev_sectors_dirty(struct bcache_device *d) |
| 8 | { |
| 9 | uint64_t i, ret = 0; |
| 10 | |
| 11 | for (i = 0; i < d->nr_stripes; i++) |
| 12 | ret += atomic_read(d->stripe_sectors_dirty + i); |
| 13 | |
| 14 | return ret; |
| 15 | } |
| 16 | |
| 17 | static inline uint64_t bcache_flash_devs_sectors_dirty(struct cache_set *c) |
| 18 | { |
| 19 | uint64_t i, ret = 0; |
| 20 | |
| 21 | mutex_lock(&bch_register_lock); |
| 22 | |
| 23 | for (i = 0; i < c->nr_uuids; i++) { |
| 24 | struct bcache_device *d = c->devices[i]; |
| 25 | |
| 26 | if (!d || !UUID_FLASH_ONLY(&c->uuids[i])) |
| 27 | continue; |
| 28 | ret += bcache_dev_sectors_dirty(d); |
| 29 | } |
| 30 | |
| 31 | mutex_unlock(&bch_register_lock); |
| 32 | |
| 33 | return ret; |
| 34 | } |
| 35 | |
| 36 | static inline unsigned offset_to_stripe(struct bcache_device *d, |
| 37 | uint64_t offset) |
| 38 | { |
| 39 | do_div(offset, d->stripe_size); |
| 40 | return offset; |
| 41 | } |
| 42 | |
| 43 | static inline bool bcache_dev_stripe_dirty(struct cached_dev *dc, |
| 44 | uint64_t offset, |
| 45 | unsigned nr_sectors) |
| 46 | { |
| 47 | unsigned stripe = offset_to_stripe(&dc->disk, offset); |
| 48 | |
| 49 | while (1) { |
| 50 | if (atomic_read(dc->disk.stripe_sectors_dirty + stripe)) |
| 51 | return true; |
| 52 | |
| 53 | if (nr_sectors <= dc->disk.stripe_size) |
| 54 | return false; |
| 55 | |
| 56 | nr_sectors -= dc->disk.stripe_size; |
| 57 | stripe++; |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | static inline bool should_writeback(struct cached_dev *dc, struct bio *bio, |
| 62 | unsigned cache_mode, bool would_skip) |
| 63 | { |
| 64 | unsigned in_use = dc->disk.c->gc_stats.in_use; |
| 65 | |
| 66 | if (cache_mode != CACHE_MODE_WRITEBACK || |
| 67 | test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || |
| 68 | in_use > CUTOFF_WRITEBACK_SYNC) |
| 69 | return false; |
| 70 | |
| 71 | if (dc->partial_stripes_expensive && |
| 72 | bcache_dev_stripe_dirty(dc, bio->bi_iter.bi_sector, |
| 73 | bio_sectors(bio))) |
| 74 | return true; |
| 75 | |
| 76 | if (would_skip) |
| 77 | return false; |
| 78 | |
| 79 | return bio->bi_rw & REQ_SYNC || |
| 80 | in_use <= CUTOFF_WRITEBACK; |
| 81 | } |
| 82 | |
| 83 | static inline void bch_writeback_queue(struct cached_dev *dc) |
| 84 | { |
| 85 | if (!IS_ERR_OR_NULL(dc->writeback_thread)) |
| 86 | wake_up_process(dc->writeback_thread); |
| 87 | } |
| 88 | |
| 89 | static inline void bch_writeback_add(struct cached_dev *dc) |
| 90 | { |
| 91 | if (!atomic_read(&dc->has_dirty) && |
| 92 | !atomic_xchg(&dc->has_dirty, 1)) { |
| 93 | atomic_inc(&dc->count); |
| 94 | |
| 95 | if (BDEV_STATE(&dc->sb) != BDEV_STATE_DIRTY) { |
| 96 | SET_BDEV_STATE(&dc->sb, BDEV_STATE_DIRTY); |
| 97 | /* XXX: should do this synchronously */ |
| 98 | bch_write_bdev_super(dc, NULL); |
| 99 | } |
| 100 | |
| 101 | bch_writeback_queue(dc); |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | void bcache_dev_sectors_dirty_add(struct cache_set *, unsigned, uint64_t, int); |
| 106 | |
| 107 | void bch_sectors_dirty_init(struct bcache_device *); |
| 108 | void bch_cached_dev_writeback_init(struct cached_dev *); |
| 109 | int bch_cached_dev_writeback_start(struct cached_dev *); |
| 110 | |
| 111 | #endif |