fs/proc/thread_self.c: code cleanup for proc_setup_thread_self()

Remove unnecessary ERR_PTR()/PTR_ERR() cast in proc_setup_thread_self().

Link: http://lkml.kernel.org/r/20190124030150.8472-2-cgxu519@gmx.com
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c
index b905010..f61ae53 100644
--- a/fs/proc/thread_self.c
+++ b/fs/proc/thread_self.c
@@ -38,6 +38,7 @@ int proc_setup_thread_self(struct super_block *s)
 	struct inode *root_inode = d_inode(s->s_root);
 	struct pid_namespace *ns = proc_pid_ns(root_inode);
 	struct dentry *thread_self;
+	int ret = -ENOMEM;
 
 	inode_lock(root_inode);
 	thread_self = d_alloc_name(s->s_root, "thread-self");
@@ -51,20 +52,19 @@ int proc_setup_thread_self(struct super_block *s)
 			inode->i_gid = GLOBAL_ROOT_GID;
 			inode->i_op = &proc_thread_self_inode_operations;
 			d_add(thread_self, inode);
+			ret = 0;
 		} else {
 			dput(thread_self);
-			thread_self = ERR_PTR(-ENOMEM);
 		}
-	} else {
-		thread_self = ERR_PTR(-ENOMEM);
 	}
 	inode_unlock(root_inode);
-	if (IS_ERR(thread_self)) {
+
+	if (ret)
 		pr_err("proc_fill_super: can't allocate /proc/thread_self\n");
-		return PTR_ERR(thread_self);
-	}
-	ns->proc_thread_self = thread_self;
-	return 0;
+	else
+		ns->proc_thread_self = thread_self;
+
+	return ret;
 }
 
 void __init proc_thread_self_init(void)