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 e28f21b9534..cf4e6cdfd15 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;  }  |