X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=kernel%2Fcgroup.c;h=f4ea4b6f3cf1eae8725ab6107f20bab58324f103;hb=90597b6cfc1fc9926a4d54f09bbf5b3254b1b028;hp=c6877fe9a831057759899555326d55933c1b467b;hpb=69a7aebcf019ab3ff5764525ad6858fbe23bb86d;p=~andy%2Flinux

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index c6877fe9a83..f4ea4b6f3cf 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1472,7 +1472,6 @@ static int cgroup_get_rootdir(struct super_block *sb)
 
 	struct inode *inode =
 		cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb);
-	struct dentry *dentry;
 
 	if (!inode)
 		return -ENOMEM;
@@ -1481,12 +1480,9 @@ static int cgroup_get_rootdir(struct super_block *sb)
 	inode->i_op = &cgroup_dir_inode_operations;
 	/* directories start off with i_nlink == 2 (for "." entry) */
 	inc_nlink(inode);
-	dentry = d_alloc_root(inode);
-	if (!dentry) {
-		iput(inode);
+	sb->s_root = d_make_root(inode);
+	if (!sb->s_root)
 		return -ENOMEM;
-	}
-	sb->s_root = dentry;
 	/* for everything else we want ->d_op set */
 	sb->s_d_op = &cgroup_dops;
 	return 0;
@@ -4885,9 +4881,9 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
 
 	rcu_assign_pointer(id->css, NULL);
 	rcu_assign_pointer(css->id, NULL);
-	write_lock(&ss->id_lock);
+	spin_lock(&ss->id_lock);
 	idr_remove(&ss->idr, id->id);
-	write_unlock(&ss->id_lock);
+	spin_unlock(&ss->id_lock);
 	kfree_rcu(id, rcu_head);
 }
 EXPORT_SYMBOL_GPL(free_css_id);
@@ -4913,10 +4909,10 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
 		error = -ENOMEM;
 		goto err_out;
 	}
-	write_lock(&ss->id_lock);
+	spin_lock(&ss->id_lock);
 	/* Don't use 0. allocates an ID of 1-65535 */
 	error = idr_get_new_above(&ss->idr, newid, 1, &myid);
-	write_unlock(&ss->id_lock);
+	spin_unlock(&ss->id_lock);
 
 	/* Returns error when there are no free spaces for new ID.*/
 	if (error) {
@@ -4931,9 +4927,9 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
 	return newid;
 remove_idr:
 	error = -ENOSPC;
-	write_lock(&ss->id_lock);
+	spin_lock(&ss->id_lock);
 	idr_remove(&ss->idr, myid);
-	write_unlock(&ss->id_lock);
+	spin_unlock(&ss->id_lock);
 err_out:
 	kfree(newid);
 	return ERR_PTR(error);
@@ -4945,7 +4941,7 @@ static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss,
 {
 	struct css_id *newid;
 
-	rwlock_init(&ss->id_lock);
+	spin_lock_init(&ss->id_lock);
 	idr_init(&ss->idr);
 
 	newid = get_new_cssid(ss, 0);
@@ -5033,6 +5029,8 @@ css_get_next(struct cgroup_subsys *ss, int id,
 		return NULL;
 
 	BUG_ON(!ss->use_id);
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
 	/* fill start point for scan */
 	tmpid = id;
 	while (1) {
@@ -5040,10 +5038,7 @@ css_get_next(struct cgroup_subsys *ss, int id,
 		 * scan next entry from bitmap(tree), tmpid is updated after
 		 * idr_get_next().
 		 */
-		read_lock(&ss->id_lock);
 		tmp = idr_get_next(&ss->idr, &tmpid);
-		read_unlock(&ss->id_lock);
-
 		if (!tmp)
 			break;
 		if (tmp->depth >= depth && tmp->stack[depth] == rootid) {