1 files changed, 64 insertions, 81 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 0dcbbeacaadc..628ae71094f2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2500,44 +2500,6 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
 		return 0;
 	}
 
-	if (btrfs_delayed_ref_is_head(node)) {
-		struct btrfs_delayed_ref_head *head;
-		/*
-		 * we've hit the end of the chain and we were supposed
-		 * to insert this extent into the tree.  But, it got
-		 * deleted before we ever needed to insert it, so all
-		 * we have to do is clean up the accounting
-		 */
-		BUG_ON(extent_op);
-		head = btrfs_delayed_node_to_head(node);
-		trace_run_delayed_ref_head(fs_info, node, head, node->action);
-
-		if (head->total_ref_mod < 0) {
-			struct btrfs_block_group_cache *cache;
-
-			cache = btrfs_lookup_block_group(fs_info, node->bytenr);
-			ASSERT(cache);
-			percpu_counter_add(&cache->space_info->total_bytes_pinned,
-					   -node->num_bytes);
-			btrfs_put_block_group(cache);
-		}
-
-		if (insert_reserved) {
-			btrfs_pin_extent(fs_info, node->bytenr,
-					 node->num_bytes, 1);
-			if (head->is_data) {
-				ret = btrfs_del_csums(trans, fs_info,
-						      node->bytenr,
-						      node->num_bytes);
-			}
-		}
-
-		/* Also free its reserved qgroup space */
-		btrfs_qgroup_free_delayed_ref(fs_info, head->qgroup_ref_root,
-					      head->qgroup_reserved);
-		return ret;
-	}
-
 	if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
 	    node->type == BTRFS_SHARED_BLOCK_REF_KEY)
 		ret = run_delayed_tree_ref(trans, fs_info, node, extent_op,
@@ -2639,6 +2601,43 @@ static int cleanup_ref_head(struct btrfs_trans_handle *trans,
 	delayed_refs->num_heads--;
 	rb_erase(&head->href_node, &delayed_refs->href_root);
 	spin_unlock(&delayed_refs->lock);
+	spin_unlock(&head->lock);
+	atomic_dec(&delayed_refs->num_entries);
+
+	trace_run_delayed_ref_head(fs_info, &head->node, head,
+				   head->node.action);
+
+	if (head->total_ref_mod < 0) {
+		struct btrfs_block_group_cache *cache;
+
+		cache = btrfs_lookup_block_group(fs_info, head->node.bytenr);
+		ASSERT(cache);
+		percpu_counter_add(&cache->space_info->total_bytes_pinned,
+				   -head->node.num_bytes);
+		btrfs_put_block_group(cache);
+
+		if (head->is_data) {
+			spin_lock(&delayed_refs->lock);
+			delayed_refs->pending_csums -= head->node.num_bytes;
+			spin_unlock(&delayed_refs->lock);
+		}
+	}
+
+	if (head->must_insert_reserved) {
+		btrfs_pin_extent(fs_info, head->node.bytenr,
+				 head->node.num_bytes, 1);
+		if (head->is_data) {
+			ret = btrfs_del_csums(trans, fs_info,
+					      head->node.bytenr,
+					      head->node.num_bytes);
+		}
+	}
+
+	/* Also free its reserved qgroup space */
+	btrfs_qgroup_free_delayed_ref(fs_info, head->qgroup_ref_root,
+				      head->qgroup_reserved);
+	btrfs_delayed_ref_unlock(head);
+	btrfs_put_delayed_ref(&head->node);
 	return 0;
 }
 
@@ -2722,6 +2721,10 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			continue;
 		}
 
+		/*
+		 * We're done processing refs in this ref_head, clean everything
+		 * up and move on to the next ref_head.
+		 */
 		if (!ref) {
 			ret = cleanup_ref_head(trans, fs_info, locked_ref);
 			if (ret > 0 ) {
@@ -2731,34 +2734,30 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			} else if (ret) {
 				return ret;
 			}
+			locked_ref = NULL;
+			count++;
+			continue;
+		}
 
-			/*
-			 * All delayed refs have been processed, Go ahead and
-			 * send the head node to run_one_delayed_ref, so that
-			 * any accounting fixes can happen
-			 */
-			ref = &locked_ref->node;
-		} else {
-			actual_count++;
-			ref->in_tree = 0;
-			list_del(&ref->list);
-			if (!list_empty(&ref->add_list))
-				list_del(&ref->add_list);
-			/*
-			 * when we play the delayed ref, also correct the
-			 * ref_mod on head
-			 */
-			switch (ref->action) {
-			case BTRFS_ADD_DELAYED_REF:
-			case BTRFS_ADD_DELAYED_EXTENT:
-				locked_ref->node.ref_mod -= ref->ref_mod;
-				break;
-			case BTRFS_DROP_DELAYED_REF:
-				locked_ref->node.ref_mod += ref->ref_mod;
-				break;
-			default:
-				WARN_ON(1);
-			}
+		actual_count++;
+		ref->in_tree = 0;
+		list_del(&ref->list);
+		if (!list_empty(&ref->add_list))
+			list_del(&ref->add_list);
+		/*
+		 * When we play the delayed ref, also correct the ref_mod on
+		 * head
+		 */
+		switch (ref->action) {
+		case BTRFS_ADD_DELAYED_REF:
+		case BTRFS_ADD_DELAYED_EXTENT:
+			locked_ref->node.ref_mod -= ref->ref_mod;
+			break;
+		case BTRFS_DROP_DELAYED_REF:
+			locked_ref->node.ref_mod += ref->ref_mod;
+			break;
+		default:
+			WARN_ON(1);
 		}
 		atomic_dec(&delayed_refs->num_entries);
 
@@ -2785,22 +2784,6 @@ static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			return ret;
 		}
 
-		/*
-		 * If this node is a head, that means all the refs in this head
-		 * have been dealt with, and we will pick the next head to deal
-		 * with, so we must unlock the head and drop it from the cluster
-		 * list before we release it.
-		 */
-		if (btrfs_delayed_ref_is_head(ref)) {
-			if (locked_ref->is_data &&
-			    locked_ref->total_ref_mod < 0) {
-				spin_lock(&delayed_refs->lock);
-				delayed_refs->pending_csums -= ref->num_bytes;
-				spin_unlock(&delayed_refs->lock);
-			}
-			btrfs_delayed_ref_unlock(locked_ref);
-			locked_ref = NULL;
-		}
 		btrfs_put_delayed_ref(ref);
 		count++;
 		cond_resched();