diff options
Diffstat (limited to 'fs/mbcache.c')
| -rw-r--r-- | fs/mbcache.c | 168 |
1 files changed, 50 insertions, 118 deletions
diff --git a/fs/mbcache.c b/fs/mbcache.c index e28f21b95344..cf4e6cdfd15b 100644 --- a/fs/mbcache.c +++ b/fs/mbcache.c @@ -79,15 +79,11 @@ EXPORT_SYMBOL(mb_cache_entry_find_next); struct mb_cache { struct list_head c_cache_list; const char *c_name; - struct mb_cache_op c_op; atomic_t c_entry_count; int c_bucket_bits; -#ifndef MB_CACHE_INDEXES_COUNT - int c_indexes_count; -#endif - struct kmem_cache *c_entry_cache; + struct kmem_cache *c_entry_cache; struct list_head *c_block_hash; - struct list_head *c_indexes_hash[0]; + struct list_head *c_index_hash; }; @@ -101,16 +97,6 @@ static LIST_HEAD(mb_cache_list); static LIST_HEAD(mb_cache_lru_list); static DEFINE_SPINLOCK(mb_cache_spinlock); -static inline int -mb_cache_indexes(struct mb_cache *cache) -{ -#ifdef MB_CACHE_INDEXES_COUNT - return MB_CACHE_INDEXES_COUNT; -#else - return cache->c_indexes_count; -#endif -} - /* * What the mbcache registers as to get shrunk dynamically. */ @@ -132,12 +118,9 @@ __mb_cache_entry_is_hashed(struct mb_cache_entry *ce) static void __mb_cache_entry_unhash(struct mb_cache_entry *ce) { - int n; - if (__mb_cache_entry_is_hashed(ce)) { list_del_init(&ce->e_block_list); - for (n=0; n<mb_cache_indexes(ce->e_cache); n++) - list_del(&ce->e_indexes[n].o_list); + list_del(&ce->e_index.o_list); } } @@ -148,16 +131,8 @@ __mb_cache_entry_forget(struct mb_cache_entry *ce, gfp_t gfp_mask) struct mb_cache *cache = ce->e_cache; mb_assert(!(ce->e_used || ce->e_queued)); - if (cache->c_op.free && cache->c_op.free(ce, gfp_mask)) { - /* free failed -- put back on the lru list - for freeing later. */ - spin_lock(&mb_cache_spinlock); - list_add(&ce->e_lru_list, &mb_cache_lru_list); - spin_unlock(&mb_cache_spinlock); - } else { - kmem_cache_free(cache->c_entry_cache, ce); - atomic_dec(&cache->c_entry_count); - } + kmem_cache_free(cache->c_entry_cache, ce); + atomic_dec(&cache->c_entry_count); } @@ -201,22 +176,12 @@ static int mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) { LIST_HEAD(free_list); - struct list_head *l, *ltmp; + struct mb_cache *cache; + struct mb_cache_entry *entry, *tmp; int count = 0; - spin_lock(&mb_cache_spinlock); - list_for_each(l, &mb_cache_list) { - struct mb_cache *cache = - list_entry(l, struct mb_cache, c_cache_list); - mb_debug("cache %s (%d)", cache->c_name, - atomic_read(&cache->c_entry_count)); - count += atomic_read(&cache->c_entry_count); - } mb_debug("trying to free %d entries", nr_to_scan); - if (nr_to_scan == 0) { - spin_unlock(&mb_cache_spinlock); - goto out; - } + spin_lock(&mb_cache_spinlock); while (nr_to_scan-- && !list_empty(&mb_cache_lru_list)) { struct mb_cache_entry *ce = list_entry(mb_cache_lru_list.next, @@ -224,12 +189,15 @@ mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) list_move_tail(&ce->e_lru_list, &free_list); __mb_cache_entry_unhash(ce); } + list_for_each_entry(cache, &mb_cache_list, c_cache_list) { + mb_debug("cache %s (%d)", cache->c_name, + atomic_read(&cache->c_entry_count)); + count += atomic_read(&cache->c_entry_count); + } spin_unlock(&mb_cache_spinlock); - list_for_each_safe(l, ltmp, &free_list) { - __mb_cache_entry_forget(list_entry(l, struct mb_cache_entry, - e_lru_list), gfp_mask); + list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) { + __mb_cache_entry_forget(entry, gfp_mask); } -out: return (count / 100) * sysctl_vfs_cache_pressure; } @@ -243,72 +211,49 @@ out: * memory was available. * * @name: name of the cache (informal) - * @cache_op: contains the callback called when freeing a cache entry - * @entry_size: The size of a cache entry, including - * struct mb_cache_entry - * @indexes_count: number of additional indexes in the cache. Must equal - * MB_CACHE_INDEXES_COUNT if the number of indexes is - * hardwired. * @bucket_bits: log2(number of hash buckets) */ struct mb_cache * -mb_cache_create(const char *name, struct mb_cache_op *cache_op, - size_t entry_size, int indexes_count, int bucket_bits) +mb_cache_create(const char *name, int bucket_bits) { - int m=0, n, bucket_count = 1 << bucket_bits; + int n, bucket_count = 1 << bucket_bits; struct mb_cache *cache = NULL; - if(entry_size < sizeof(struct mb_cache_entry) + - indexes_count * sizeof(((struct mb_cache_entry *) 0)->e_indexes[0])) - return NULL; - - cache = kmalloc(sizeof(struct mb_cache) + - indexes_count * sizeof(struct list_head), GFP_KERNEL); + cache = kmalloc(sizeof(struct mb_cache), GFP_KERNEL); if (!cache) - goto fail; + return NULL; cache->c_name = name; - cache->c_op.free = NULL; - if (cache_op) - cache->c_op.free = cache_op->free; atomic_set(&cache->c_entry_count, 0); cache->c_bucket_bits = bucket_bits; -#ifdef MB_CACHE_INDEXES_COUNT - mb_assert(indexes_count == MB_CACHE_INDEXES_COUNT); -#else - cache->c_indexes_count = indexes_count; -#endif cache->c_block_hash = kmalloc(bucket_count * sizeof(struct list_head), GFP_KERNEL); if (!cache->c_block_hash) goto fail; for (n=0; n<bucket_count; n++) INIT_LIST_HEAD(&cache->c_block_hash[n]); - for (m=0; m<indexes_count; m++) { - cache->c_indexes_hash[m] = kmalloc(bucket_count * - sizeof(struct list_head), - GFP_KERNEL); - if (!cache->c_indexes_hash[m]) - goto fail; - for (n=0; n<bucket_count; n++) - INIT_LIST_HEAD(&cache->c_indexes_hash[m][n]); - } - cache->c_entry_cache = kmem_cache_create(name, entry_size, 0, + cache->c_index_hash = kmalloc(bucket_count * sizeof(struct list_head), + GFP_KERNEL); + if (!cache->c_index_hash) + goto fail; + for (n=0; n<bucket_count; n++) + INIT_LIST_HEAD(&cache->c_index_hash[n]); + cache->c_entry_cache = kmem_cache_create(name, + sizeof(struct mb_cache_entry), 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); if (!cache->c_entry_cache) - goto fail; + goto fail2; spin_lock(&mb_cache_spinlock); list_add(&cache->c_cache_list, &mb_cache_list); spin_unlock(&mb_cache_spinlock); return cache; +fail2: + kfree(cache->c_index_hash); + fail: - if (cache) { - while (--m >= 0) - kfree(cache->c_indexes_hash[m]); - kfree(cache->c_block_hash); - kfree(cache); - } + kfree(cache->c_block_hash); + kfree(cache); return NULL; } @@ -357,7 +302,6 @@ mb_cache_destroy(struct mb_cache *cache) { LIST_HEAD(free_list); struct list_head *l, *ltmp; - int n; spin_lock(&mb_cache_spinlock); list_for_each_safe(l, ltmp, &mb_cache_lru_list) { @@ -384,8 +328,7 @@ mb_cache_destroy(struct mb_cache *cache) kmem_cache_destroy(cache->c_entry_cache); - for (n=0; n < mb_cache_indexes(cache); n++) - kfree(cache->c_indexes_hash[n]); + kfree(cache->c_index_hash); kfree(cache->c_block_hash); kfree(cache); } @@ -429,17 +372,16 @@ mb_cache_entry_alloc(struct mb_cache *cache, gfp_t gfp_flags) * * @bdev: device the cache entry belongs to * @block: block number - * @keys: array of additional keys. There must be indexes_count entries - * in the array (as specified when creating the cache). + * @key: lookup key */ int mb_cache_entry_insert(struct mb_cache_entry *ce, struct block_device *bdev, - sector_t block, unsigned int keys[]) + sector_t block, unsigned int key) { struct mb_cache *cache = ce->e_cache; unsigned int bucket; struct list_head *l; - int error = -EBUSY, n; + int error = -EBUSY; bucket = hash_long((unsigned long)bdev + (block & 0xffffffff), cache->c_bucket_bits); @@ -454,12 +396,9 @@ mb_cache_entry_insert(struct mb_cache_entry *ce, struct block_device *bdev, ce->e_bdev = bdev; ce->e_block = block; list_add(&ce->e_block_list, &cache->c_block_hash[bucket]); - for (n=0; n<mb_cache_indexes(cache); n++) { - ce->e_indexes[n].o_key = keys[n]; - bucket = hash_long(keys[n], cache->c_bucket_bits); - list_add(&ce->e_indexes[n].o_list, - &cache->c_indexes_hash[n][bucket]); - } + ce->e_index.o_key = key; + bucket = hash_long(key, cache->c_bucket_bits); + list_add(&ce->e_index.o_list, &cache->c_index_hash[bucket]); error = 0; out: spin_unlock(&mb_cache_spinlock); @@ -555,13 +494,12 @@ cleanup: static struct mb_cache_entry * __mb_cache_entry_find(struct list_head *l, struct list_head *head, - int index, struct block_device *bdev, unsigned int key) + struct block_device *bdev, unsigned int key) { while (l != head) { struct mb_cache_entry *ce = - list_entry(l, struct mb_cache_entry, - e_indexes[index].o_list); - if (ce->e_bdev == bdev && ce->e_indexes[index].o_key == key) { + list_entry(l, struct mb_cache_entry, e_index.o_list); + if (ce->e_bdev == bdev && ce->e_index.o_key == key) { DEFINE_WAIT(wait); if (!list_empty(&ce->e_lru_list)) @@ -603,23 +541,20 @@ __mb_cache_entry_find(struct list_head *l, struct list_head *head, * returned cache entry is locked for shared access ("multiple readers"). * * @cache: the cache to search - * @index: the number of the additonal index to search (0<=index<indexes_count) * @bdev: the device the cache entry should belong to * @key: the key in the index */ struct mb_cache_entry * -mb_cache_entry_find_first(struct mb_cache *cache, int index, - struct block_device *bdev, unsigned int key) +mb_cache_entry_find_first(struct mb_cache *cache, struct block_device *bdev, + unsigned int key) { unsigned int bucket = hash_long(key, cache->c_bucket_bits); struct list_head *l; struct mb_cache_entry *ce; - mb_assert(index < mb_cache_indexes(cache)); spin_lock(&mb_cache_spinlock); - l = cache->c_indexes_hash[index][bucket].next; - ce = __mb_cache_entry_find(l, &cache->c_indexes_hash[index][bucket], - index, bdev, key); + l = cache->c_index_hash[bucket].next; + ce = __mb_cache_entry_find(l, &cache->c_index_hash[bucket], bdev, key); spin_unlock(&mb_cache_spinlock); return ce; } @@ -640,12 +575,11 @@ mb_cache_entry_find_first(struct mb_cache *cache, int index, * } * * @prev: The previous match - * @index: the number of the additonal index to search (0<=index<indexes_count) * @bdev: the device the cache entry should belong to * @key: the key in the index */ struct mb_cache_entry * -mb_cache_entry_find_next(struct mb_cache_entry *prev, int index, +mb_cache_entry_find_next(struct mb_cache_entry *prev, struct block_device *bdev, unsigned int key) { struct mb_cache *cache = prev->e_cache; @@ -653,11 +587,9 @@ mb_cache_entry_find_next(struct mb_cache_entry *prev, int index, struct list_head *l; struct mb_cache_entry *ce; - mb_assert(index < mb_cache_indexes(cache)); spin_lock(&mb_cache_spinlock); - l = prev->e_indexes[index].o_list.next; - ce = __mb_cache_entry_find(l, &cache->c_indexes_hash[index][bucket], - index, bdev, key); + l = prev->e_index.o_list.next; + ce = __mb_cache_entry_find(l, &cache->c_index_hash[bucket], bdev, key); __mb_cache_entry_release_unlock(prev); return ce; } |