Re: [PATCH 05/17] btrfs: move btrfs_get_block_group helper out of disk-io.h

[Qu Wenruo <wqu@suse.com>]

On 2022/9/14 23:06, Josef Bacik wrote:
> This inline helper calls btrfs_fs_compat_ro(), which is defined in
> another header.  To avoid weird header dependency problems move this
> helper into disk-io.c with the rest of the global root helpers.

I kinda like this small function to be inlined.
As the function call cost is not that small compared to the tiny 
function body.

Mind to give some example of the problem you hit?
Maybe we can find some other solution.

Thanks,
Qu

> 
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> ---
>   fs/btrfs/disk-io.c | 7 +++++++
>   fs/btrfs/disk-io.h | 8 +-------
>   2 files changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index a887fe67a2a0..d32aa67f962b 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -1169,6 +1169,13 @@ struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr)
>   	return btrfs_global_root(fs_info, &key);
>   }
>   
> +struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
> +{
> +	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
> +		return fs_info->block_group_root;
> +	return btrfs_extent_root(fs_info, 0);
> +}
> +
>   struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
>   				     u64 objectid)
>   {
> diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
> index 7e545ec09a10..084fbe5768e1 100644
> --- a/fs/btrfs/disk-io.h
> +++ b/fs/btrfs/disk-io.h
> @@ -72,6 +72,7 @@ struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
>   				     struct btrfs_key *key);
>   struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
>   struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
> +struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info);
>   
>   void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
>   int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
> @@ -103,13 +104,6 @@ static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
>   	return NULL;
>   }
>   
> -static inline struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
> -{
> -	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
> -		return fs_info->block_group_root;
> -	return btrfs_extent_root(fs_info, 0);
> -}
> -
>   void btrfs_put_root(struct btrfs_root *root);
>   void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
>   int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,