Re: [PATCH 2/8] btrfs: relocation: use enum for stages

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

On 2023/9/22 20:37, David Sterba wrote:
> Add an enum type for data relocation stages.
>
> Signed-off-by: David Sterba <dsterba@suse.com>
> ---
>   fs/btrfs/relocation.c | 16 +++++++++-------
>   1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
> index 9ff3572a8451..3afe499f00b1 100644
> --- a/fs/btrfs/relocation.c
> +++ b/fs/btrfs/relocation.c
> @@ -125,6 +125,12 @@ struct file_extent_cluster {
>   	u64 owning_root;
>   };
>
> +/* Stages of data relocation. */
> +enum reloc_stage {
> +	MOVE_DATA_EXTENTS,
> +	UPDATE_DATA_PTRS
> +};
> +
>   struct reloc_control {
>   	/* block group to relocate */
>   	struct btrfs_block_group *block_group;
> @@ -156,16 +162,12 @@ struct reloc_control {
>   	u64 search_start;
>   	u64 extents_found;
>
> -	unsigned int stage:8;
> +	enum reloc_stage stage;

Wouldn't this cause extra hole?

Thanks,
Qu
>   	unsigned int create_reloc_tree:1;
>   	unsigned int merge_reloc_tree:1;
>   	unsigned int found_file_extent:1;
>   };
>
> -/* stages of data relocation */
> -#define MOVE_DATA_EXTENTS	0
> -#define UPDATE_DATA_PTRS	1
> -
>   static void mark_block_processed(struct reloc_control *rc,
>   				 struct btrfs_backref_node *node)
>   {
> @@ -4054,7 +4056,7 @@ static void describe_relocation(struct btrfs_fs_info *fs_info,
>   		   block_group->start, buf);
>   }
>
> -static const char *stage_to_string(int stage)
> +static const char *stage_to_string(enum reloc_stage stage)
>   {
>   	if (stage == MOVE_DATA_EXTENTS)
>   		return "move data extents";
> @@ -4170,7 +4172,7 @@ int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start)
>   	WARN_ON(ret && ret != -EAGAIN);
>
>   	while (1) {
> -		int finishes_stage;
> +		enum reloc_stage finishes_stage;
>
>   		mutex_lock(&fs_info->cleaner_mutex);
>   		ret = relocate_block_group(rc);