Re: [PATCH] btrfs: Simplify the allocation of slab caches in btrfs_delayed_inode_init

From: Johannes Thumshirn
Date: Wed Jan 31 2024 - 05:24:04 EST


On 31.01.24 07:20, Kunwu Chan wrote:
> commit 0a31bd5f2bbb ("KMEM_CACHE(): simplify slab cache creation")
> introduces a new macro.
> Use the new KMEM_CACHE() macro instead of direct kmem_cache_create

That commit is 17 years old. Why should we switch to it _now_? I
wouldn't call it a new macro.

Don't get me wrong, I don't oppose the patch, but I'd prefer a better
explanation why now and not 17 years ago when the macro got introduced.

> to simplify the creation of SLAB caches.
>
> Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
> ---
> fs/btrfs/delayed-inode.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
> index 08102883f560..8c748c6cdf6d 100644
> --- a/fs/btrfs/delayed-inode.c
> +++ b/fs/btrfs/delayed-inode.c
> @@ -28,11 +28,7 @@ static struct kmem_cache *delayed_node_cache;
>
> int __init btrfs_delayed_inode_init(void)
> {
> - delayed_node_cache = kmem_cache_create("btrfs_delayed_node",
> - sizeof(struct btrfs_delayed_node),
> - 0,
> - SLAB_MEM_SPREAD,
> - NULL);
> + delayed_node_cache = KMEM_CACHE(btrfs_delayed_node, SLAB_MEM_SPREAD);
> if (!delayed_node_cache)
> return -ENOMEM;
> return 0;