static void __attach_mnt(struct mount *mnt, struct mount *parent)
{
	hlist_add_head_rcu(&mnt->mnt_hash,
			   m_hash(&parent->mnt, mnt->mnt_mountpoint));
	list_add_tail(&mnt->mnt_child, &parent->mnt_mounts);
}
static void __attach_mnt(struct mount *mnt, struct mount *parent)
{
	hlist_add_head_rcu(&mnt->mnt_hash,
			   m_hash(&parent->mnt, mnt->mnt_mountpoint));
	list_add_tail(&mnt->mnt_child, &parent->mnt_mounts);
}