Re: [PATCH] fs: xfs: xfs_icreate_item: constify xfs_item_ops structure

From: Eric Sandeen
Date: Sat Nov 19 2016 - 22:47:37 EST



On 11/19/16 7:16 AM, Bhumika Goyal wrote:
> Declare the structure xfs_item_ops as const as it is only passed as an
> argument to the function xfs_log_item_init. As this argument is of type
> const struct xfs_item_ops *, so xfs_item_ops structures having this
> property can be declared as const.
> Done using Coccinelle:
>
> @r1 disable optional_qualifier @
> identifier i;
> position p;
> @@
> static struct xfs_item_ops i@p = {...};
>
> @ok1@
> identifier r1.i;
> position p;
> expression e1,e2,e3;
> @@
> xfs_log_item_init(e1,e2,e3,&i@p)
>
> @bad@
> position p!={r1.p,ok1.p};
> identifier r1.i;
> @@
> i@p
>
> @depends on !bad disable optional_qualifier@
> identifier r1.i;
> @@
> static
> +const
> struct xfs_item_ops i={...};
>
> @depends on !bad disable optional_qualifier@
> identifier r1.i;
> @@
> +const
> struct xfs_item_ops i;
>
> File size before:
> text data bss dec hex filename
> 737 64 8 809 329 fs/xfs/xfs_icreate_item.o
>
> File size after:
> text data bss dec hex filename
> 801 0 8 809 329 fs/xfs/xfs_icreate_item.o
>
> Signed-off-by: Bhumika Goyal <bhumirks@xxxxxxxxx>

Sure, every other xfs_item_ops structure is a const.

Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxxx>

> ---
> fs/xfs/xfs_icreate_item.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/xfs/xfs_icreate_item.c b/fs/xfs/xfs_icreate_item.c
> index d45ca72..865ad13 100644
> --- a/fs/xfs/xfs_icreate_item.c
> +++ b/fs/xfs/xfs_icreate_item.c
> @@ -133,7 +133,7 @@ static inline struct xfs_icreate_item *ICR_ITEM(struct xfs_log_item *lip)
> /*
> * This is the ops vector shared by all buf log items.
> */
> -static struct xfs_item_ops xfs_icreate_item_ops = {
> +static const struct xfs_item_ops xfs_icreate_item_ops = {
> .iop_size = xfs_icreate_item_size,
> .iop_format = xfs_icreate_item_format,
> .iop_pin = xfs_icreate_item_pin,
>