vfs: avoid taking inode_hash_lock on pipes and sockets

Some inodes (pipes, sockets, ...) are not hashed, no need to take contended inode_hash_lock at dismantle time. nice speedup on SMP machines on socket intensive workloads. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
git-mirror · Aug 1, 2011 · f2ee7ab · f2ee7ab
1 parent b12362b
commit f2ee7ab
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 4 deletions.
diff --git a/fs/inode.c b/fs/inode.c
@@ -399,20 +399,20 @@ void __insert_inode_hash(struct inode *inode, unsigned long hashval)
 EXPORT_SYMBOL(__insert_inode_hash);
 
 /**
- *	remove_inode_hash - remove an inode from the 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)
+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);
+EXPORT_SYMBOL(__remove_inode_hash);
 
 void end_writeback(struct inode *inode)
 {

diff --git a/include/linux/fs.h b/include/linux/fs.h
@@ -2317,11 +2317,18 @@ extern int should_remove_suid(struct dentry *);
 extern int file_remove_suid(struct file *);
 
 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
-extern void remove_inode_hash(struct inode *);
 static inline void insert_inode_hash(struct inode *inode)
 {
 	__insert_inode_hash(inode, inode->i_ino);
 }
+
+extern void __remove_inode_hash(struct inode *);
+static inline void remove_inode_hash(struct inode *inode)
+{
+	if (!inode_unhashed(inode))
+		__remove_inode_hash(inode);
+}
+
 extern void inode_sb_list_add(struct inode *inode);
 
 #ifdef CONFIG_BLOCK