Re: [PATCH] maple_tree: shrink struct maple_tree from 24 to 16 bytes on LP64

From: Liam R. Howlett
Date: Tue Aug 22 2023 - 11:57:21 EST


* Mateusz Guzik <mjguzik@xxxxxxxxx> [230821 18:52]:
> by plugging a padding hole.
>
> [sounds like an obvious thing to do, am I missing something?]

Thanks for the patch. There is no reason for the current ordering.

I've tested both 32 and 64 bit userspace testing to double check
everything still works.

>
> Signed-off-by: Mateusz Guzik <mjguzik@xxxxxxxxx>

Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>

> ---
> include/linux/maple_tree.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
> index 295548cca8b3..5bdd3ce34cb9 100644
> --- a/include/linux/maple_tree.h
> +++ b/include/linux/maple_tree.h
> @@ -212,8 +212,8 @@ struct maple_tree {
> spinlock_t ma_lock;
> lockdep_map_p ma_external_lock;
> };
> - void __rcu *ma_root;
> unsigned int ma_flags;
> + void __rcu *ma_root;
> };
>
> /**
> --
> 2.39.2
>
>