inode节点hash处理

static struct hlist_head *inode_hashtable __read_mostly; /*  * Initialize the waitqueues and inode hash table.  */ void __init inode_init_early(void) { unsigned int loop; /* If hashes are distributed across NUMA nodes, defer * hash allocation until vmalloc space is available. */ if (hashdist) return; inode_hashtable = alloc_large_system_hash("Inode-cache", sizeof(struct hlist_head), ihash_entries, 14, HASH_EARLY, &i_hash_shift, &i_hash_mask, 0, 0); for (loop = 0; loop < (1U << i_hash_shift); loop++) INIT_HLIST_HEAD(&inode_hashtable[loop]); } static inline void insert_inode_hash(struct inode *inode) { __insert_inode_hash(inode, inode->i_ino); } static unsigned long hash(struct super_block *sb, unsigned long hashval) { unsigned long tmp; tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / L1_CACHE_BYTES; tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> i_hash_shift); return tmp & i_hash_mask; } /**  * __insert_inode_hash - hash an inode  * @inode: unhashed inode  * @hashval: unsigned long value used to locate this object in the  * inode_hashtable.  *  * Add an inode to the inode hash for this superblock.  */ void __insert_inode_hash(struct inode *inode, unsigned long hashval) { struct hlist_head *b = inode_hashtable + hash(inode->i_sb, hashval); spin_lock(&inode_hash_lock); spin_lock(&inode->i_lock); hlist_add_head(&inode->i_hash, b); spin_unlock(&inode->i_lock); spin_unlock(&inode_hash_lock); } EXPORT_SYMBOL(__insert_inode_hash); /** * __remove_inode_hash - remove an inode from the hash * @inode: inode to unhash * * Remove an inode from the superblock. */void __remove_inode_hash(struct inode *inode){ spin_lock(&inode_hash_lock); spin_lock(&inode->i_lock); hlist_del_init(&inode->i_hash); spin_unlock(&inode->i_lock); spin_unlock(&inode_hash_lock);}EXPORT_SYMBOL(__remove_inode_hash);