Re: [PATCH v3 0/14] btrfs: Introduce macro to iterate over slots

[David Sterba <dsterba@suse.cz>]

On Wed, Mar 02, 2022 at 05:48:15PM +0100, Gabriel Niebler wrote:
> There is a common pattern when searching for a key in btrfs:
> 
> * Call btrfs_search_slot to find the slot for the key
> * Enter an endless loop:
> 	* If the found slot is larger than the no. of items in the current leaf,
> 	  check the next leaf
> 	* If it's still not found in the next leaf, terminate the loop
> 	* Otherwise do something with the found key
> 	* Increment the current slot and continue
> 
> To reduce code duplication, we can replace this code pattern with an iterator
> macro, similar to the existing for_each_X macros found elsewhere in the kernel.
> This also makes the code easier to understand for newcomers by putting a name
> to the encapsulated functionality.
> 
> This patchset survived a complete fstest run.
> 
> Changes from v2:
>  * Rename btrfs_valid_slot to btrfs_get_next_valid_item (Nikolay)
>  * Fix comment formatting (David)
>  * Remove redundant parentheses and indentation in loop condition (David)
>  * Remove redundant iter_ret var and reuse ret instead (Nikolay)
>  * Make termination condition more consistent in btrfs_unlink_all_paths
>    (Nikolay)
>  * Improved patch organisation by splitting into one patch per function (David)
>  * Improve doc comment for btrfs_get_next_valid_item (Gabriel)
>  * Remove `out` label and assoc. gotos from id_create_dir (Gabriel)
>  * Initialise `ret` in process_all_refs and process_all_new_xattrs (Gabriel)
>  * Remove unneeded btrfs_item_key_to_cpu call from loop body in
>    btrfs_read_chunk_tree (Gabriel)

I still see some of the style issues not addressed in your version, I'll
point them out in the first example I find but it needs to be fixed in
all of them. Otherwise it looks good. As we're near the code freeze for
5.17 I'm not sure I could put it there so it's 5.18 at the latest.