diff options
| -rw-r--r-- | fs/btrfs/lru_cache.c | 12 | ||||
| -rw-r--r-- | fs/btrfs/lru_cache.h | 9 | ||||
| -rw-r--r-- | fs/btrfs/send.c | 8 |
3 files changed, 20 insertions, 9 deletions
diff --git a/fs/btrfs/lru_cache.c b/fs/btrfs/lru_cache.c index 6012bceedffc..01821d66a8a2 100644 --- a/fs/btrfs/lru_cache.c +++ b/fs/btrfs/lru_cache.c @@ -18,12 +18,13 @@ void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size) cache->max_size = max_size; } -static struct btrfs_lru_cache_entry *match_entry(struct list_head *head, u64 key) +static struct btrfs_lru_cache_entry *match_entry(struct list_head *head, u64 key, + u64 gen) { struct btrfs_lru_cache_entry *entry; list_for_each_entry(entry, head, list) { - if (entry->key == key) + if (entry->key == key && entry->gen == gen) return entry; } @@ -35,11 +36,12 @@ static struct btrfs_lru_cache_entry *match_entry(struct list_head *head, u64 key * * @cache: The cache. * @key: The key of the entry we are looking for. + * @gen: Generation associated to the key. * * Returns the entry associated with the key or NULL if none found. */ struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache, - u64 key) + u64 key, u64 gen) { struct list_head *head; struct btrfs_lru_cache_entry *entry; @@ -48,7 +50,7 @@ struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cac if (!head) return NULL; - entry = match_entry(head, key); + entry = match_entry(head, key, gen); if (entry) list_move_tail(&entry->lru_list, &cache->lru_list); @@ -111,7 +113,7 @@ int btrfs_lru_cache_store(struct btrfs_lru_cache *cache, kfree(head); head = mtree_load(&cache->entries, key); ASSERT(head != NULL); - if (match_entry(head, key) != NULL) + if (match_entry(head, key, new_entry->gen) != NULL) return -EEXIST; list_add_tail(&new_entry->list, head); } else if (ret < 0) { diff --git a/fs/btrfs/lru_cache.h b/fs/btrfs/lru_cache.h index 7a255cd2958e..c1f20f4b7038 100644 --- a/fs/btrfs/lru_cache.h +++ b/fs/btrfs/lru_cache.h @@ -18,6 +18,13 @@ struct btrfs_lru_cache_entry { struct list_head lru_list; u64 key; /* + * Optional generation associated to a key. Use 0 if not needed/used. + * Entries with the same key and different generations are stored in a + * linked list, so use this only for cases where there's a small number + * of different generations. + */ + u64 gen; + /* * The maple tree uses unsigned long type for the keys, which is 32 bits * on 32 bits systems, and 64 bits on 64 bits systems. So if we want to * use something like inode numbers as keys, which are always a u64, we @@ -47,7 +54,7 @@ static inline unsigned int btrfs_lru_cache_size(const struct btrfs_lru_cache *ca void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size); struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache, - u64 key); + u64 key, u64 gen); int btrfs_lru_cache_store(struct btrfs_lru_cache *cache, struct btrfs_lru_cache_entry *new_entry, gfp_t gfp); diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 1cde74638939..8a7d8979bf57 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -120,7 +120,7 @@ static_assert(offsetof(struct backref_cache_entry, entry) == 0); /* * Max number of entries in the cache that stores directories that were already * created. The cache uses raw struct btrfs_lru_cache_entry entries, so it uses - * at most 4096 bytes - sizeof(struct btrfs_lru_cache_entry) is 40 bytes, but + * at most 4096 bytes - sizeof(struct btrfs_lru_cache_entry) is 48 bytes, but * the kmalloc-64 slab is used, so we get 4096 bytes (64 bytes * 64). */ #define SEND_MAX_DIR_CREATED_CACHE_SIZE 64 @@ -1422,7 +1422,7 @@ static bool lookup_backref_cache(u64 leaf_bytenr, void *ctx, return false; } - raw_entry = btrfs_lru_cache_lookup(&sctx->backref_cache, key); + raw_entry = btrfs_lru_cache_lookup(&sctx->backref_cache, key, 0); if (!raw_entry) return false; @@ -1455,6 +1455,7 @@ static void store_backref_cache(u64 leaf_bytenr, const struct ulist *root_ids, return; new_entry->entry.key = leaf_bytenr >> fs_info->sectorsize_bits; + new_entry->entry.gen = 0; new_entry->num_roots = 0; ULIST_ITER_INIT(&uiter); while ((node = ulist_next(root_ids, &uiter)) != NULL) { @@ -2957,6 +2958,7 @@ static void cache_dir_created(struct send_ctx *sctx, u64 dir) return; entry->key = dir; + entry->gen = 0; ret = btrfs_lru_cache_store(&sctx->dir_created_cache, entry, GFP_KERNEL); if (ret < 0) kfree(entry); @@ -2977,7 +2979,7 @@ static int did_create_dir(struct send_ctx *sctx, u64 dir) struct btrfs_key di_key; struct btrfs_dir_item *di; - if (btrfs_lru_cache_lookup(&sctx->dir_created_cache, dir)) + if (btrfs_lru_cache_lookup(&sctx->dir_created_cache, dir, 0)) return 1; path = alloc_path_for_send(); |