Re: [PATCH 13/29] btrfs: __btrfs_wait_marked_extents rename werr to ret err to ret2

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

在 2024/3/20 01:25, Anand Jain 写道:
> Rename the function's local variable werr to ret, and err to ret2.
> Also, align these two variable declarations with the other declarations in
> the function for better function space alignment.
>
> Signed-off-by: Anand Jain <anand.jain@oracle.com>

Again, not a fan of @ret2.

And IIRC we can declare the variable used inside the loop local, by
making sure we set the global ret properly before breaking the loop.

Thanks,
Qu
> ---
>   fs/btrfs/transaction.c | 26 +++++++++++++-------------
>   1 file changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
> index 167893457b58..f344f97a6035 100644
> --- a/fs/btrfs/transaction.c
> +++ b/fs/btrfs/transaction.c
> @@ -1173,12 +1173,12 @@ int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
>   static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
>   				       struct extent_io_tree *dirty_pages)
>   {
> -	int err = 0;
> -	int werr = 0;
>   	struct address_space *mapping = fs_info->btree_inode->i_mapping;
>   	struct extent_state *cached_state = NULL;
>   	u64 start = 0;
>   	u64 end;
> +	int ret = 0;
> +	int ret2 = 0;
>
>   	while (find_first_extent_bit(dirty_pages, start, &start, &end,
>   				     EXTENT_NEED_WAIT, &cached_state)) {
> @@ -1190,22 +1190,22 @@ static int __btrfs_wait_marked_extents(struct btrfs_fs_info *fs_info,
>   		 * concurrently - we do it only at transaction commit time when
>   		 * it's safe to do it (through extent_io_tree_release()).
>   		 */
> -		err = clear_extent_bit(dirty_pages, start, end,
> -				       EXTENT_NEED_WAIT, &cached_state);
> -		if (err == -ENOMEM)
> -			err = 0;
> -		if (!err)
> -			err = filemap_fdatawait_range(mapping, start, end);
> -		if (err)
> -			werr = err;
> +		ret2 = clear_extent_bit(dirty_pages, start, end,
> +					EXTENT_NEED_WAIT, &cached_state);
> +		if (ret2 == -ENOMEM)
> +			ret2 = 0;
> +		if (!ret2)
> +			ret2 = filemap_fdatawait_range(mapping, start, end);
> +		if (ret2)
> +			ret = ret2;
>   		free_extent_state(cached_state);
>   		cached_state = NULL;
>   		cond_resched();
>   		start = end + 1;
>   	}
> -	if (err)
> -		werr = err;
> -	return werr;
> +	if (ret2)
> +		ret = ret2;
> +	return ret;
>   }
>
>   static int btrfs_wait_extents(struct btrfs_fs_info *fs_info,