btrfs: remove unlikely from NULL checks

Unlikely is implicit for NULL checks of pointers.
Signed-off-by: David Sterba <dsterba@suse.cz>

fs/btrfs/async-thread.c

@@ -92,7 +92,7 @@ __btrfs_alloc_workqueue(const char *name, int flags, int max_active,
 {
 	struct __btrfs_workqueue *ret = kzalloc(sizeof(*ret), GFP_NOFS);
 
-	if (unlikely(!ret))
+	if (!ret)
 		return NULL;
 
 	ret->max_active = max_active;
@@ -116,7 +116,7 @@ __btrfs_alloc_workqueue(const char *name, int flags, int max_active,
 		ret->normal_wq = alloc_workqueue("%s-%s", flags,
 						 ret->max_active, "btrfs",
 						 name);
-	if (unlikely(!ret->normal_wq)) {
+	if (!ret->normal_wq) {
 		kfree(ret);
 		return NULL;
 	}
@@ -138,12 +138,12 @@ struct btrfs_workqueue *btrfs_alloc_workqueue(const char *name,
 {
 	struct btrfs_workqueue *ret = kzalloc(sizeof(*ret), GFP_NOFS);
 
-	if (unlikely(!ret))
+	if (!ret)
 		return NULL;
 
 	ret->normal = __btrfs_alloc_workqueue(name, flags & ~WQ_HIGHPRI,
 					      max_active, thresh);
-	if (unlikely(!ret->normal)) {
+	if (!ret->normal) {
 		kfree(ret);
 		return NULL;
 	}
@@ -151,7 +151,7 @@ struct btrfs_workqueue *btrfs_alloc_workqueue(const char *name,
 	if (flags & WQ_HIGHPRI) {
 		ret->high = __btrfs_alloc_workqueue(name, flags, max_active,
 						    thresh);
-		if (unlikely(!ret->high)) {
+		if (!ret->high) {
 			__btrfs_destroy_workqueue(ret->normal);
 			kfree(ret);
 			return NULL;

fs/btrfs/inode.c

@@ -9013,7 +9013,7 @@ static int __start_delalloc_inodes(struct btrfs_root *root, int delay_iput,
 		spin_unlock(&root->delalloc_lock);
 
 		work = btrfs_alloc_delalloc_work(inode, 0, delay_iput);
-		if (unlikely(!work)) {
+		if (!work) {
 			if (delay_iput)
 				btrfs_add_delayed_iput(inode);
 			else