Re: [PATCH v2] btrfs: Turn delayed_nodes_tree into an XArray

[David Sterba <dsterba@suse.cz>]

On Tue, Apr 12, 2022 at 02:35:46PM +0200, Gabriel Niebler wrote:
> … in the btrfs_root struct. Also adjust all usages of this object to use
> the XArray API.
> 
> Signed-off-by: Gabriel Niebler <gniebler@suse.com>
> ---
> 
> Notes:
>     XArrays offer a somewhat nicer API than radix trees and were implemented
>     specifically to replace the latter. They utilize the exact same underlying
>     data structure, but their API is notionally easier to use, as it provides
>     array semantics to the user of radix trees. The higher level API also
>     takes care of locking, adding even more ease of use.
>     
>     The btrfs code uses radix trees in several places. This patch only
>     converts the `delayed_nodes_tree` member of the btrfs_root struct.

You've put this under the --- marker which means this is not supposed to
be in the changelog (as we do for various patch revision commments) but
then there would be basically no useful changelog left. That the
conversion is done is clear, maybe there are some useful notes or
comments what changed and how, eg. the locking.