btrfs: only track ref_heads in delayed_ref_updates (158ffa36) · Commits · 戴 / test

We use this number to figure out how many delayed refs to run, but __btrfs_run_delayed_refs really only checks every time we need a new delayed ref head, so we always run at least one ref head completely no matter what the number of items on it. Fix the accounting to only be adjusted when we add/remove a ref head. In addition to using this number to limit the number of delayed refs run, a future patch is also going to use it to calculate the amount of space required for delayed refs space reservation. Reviewed-by:

Nikolay Borisov <nborisov@suse.com> Signed-off-by:

Josef Bacik <jbacik@fb.com> Signed-off-by:

David Sterba <dsterba@suse.com>

fs/btrfs/delayed-ref.c

+0 −3

Original line number	Original line	Diff line number	Diff line
	@@ -251,8 +251,6 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans,
	ref->in_tree = 0;		ref->in_tree = 0;
	btrfs_put_delayed_ref(ref);		btrfs_put_delayed_ref(ref);
	atomic_dec(&delayed_refs->num_entries);		atomic_dec(&delayed_refs->num_entries);
	if (trans->delayed_ref_updates)
	trans->delayed_ref_updates--;
	}		}

	static bool merge_ref(struct btrfs_trans_handle *trans,		static bool merge_ref(struct btrfs_trans_handle *trans,
	@@ -467,7 +465,6 @@ inserted:
	if (ref->action == BTRFS_ADD_DELAYED_REF)		if (ref->action == BTRFS_ADD_DELAYED_REF)
	list_add_tail(&ref->add_list, &href->ref_add_list);		list_add_tail(&ref->add_list, &href->ref_add_list);
	atomic_inc(&root->num_entries);		atomic_inc(&root->num_entries);
	trans->delayed_ref_updates++;
	spin_unlock(&href->lock);		spin_unlock(&href->lock);
	return ret;		return ret;
	}		}

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