Re: [PATCH] net/xdp: remove unused macro REG_STATE_NEW

From: John Fastabend
Date: Mon Nov 09 2020 - 16:44:59 EST


Alex Shi wrote:
>
>
> 在 2020/11/7 上午12:13, Jesper Dangaard Brouer 写道:
> > Hmm... REG_STATE_NEW is zero, so it is implicitly set via memset zero.
> > But it is true that it is technically not directly used or referenced.
> >
> > It is mentioned in a comment, so please send V2 with this additional change:
>
> Hi Jesper,
>
> Thanks a lot for comments. here is the v2:
>
> From 2908d25bf2e1c90ad71a83ba056743f45da283e8 Mon Sep 17 00:00:00 2001
> From: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
> Date: Fri, 6 Nov 2020 13:41:58 +0800
> Subject: [PATCH v2] net/xdp: remove unused macro REG_STATE_NEW
>
> To tame gcc warning on it:
> net/core/xdp.c:20:0: warning: macro "REG_STATE_NEW" is not used
> [-Wunused-macros]
> And change related comments as Jesper Dangaard Brouer suggested.
>
> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
> ---

> net/core/xdp.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/net/core/xdp.c b/net/core/xdp.c
> index 48aba933a5a8..0df5ee5682d9 100644
> --- a/net/core/xdp.c
> +++ b/net/core/xdp.c
> @@ -19,7 +19,6 @@
> #include <trace/events/xdp.h>
> #include <net/xdp_sock_drv.h>
>
> -#define REG_STATE_NEW 0x0
> #define REG_STATE_REGISTERED 0x1
> #define REG_STATE_UNREGISTERED 0x2
> #define REG_STATE_UNUSED 0x3

I think having the define there makes it more readable and clear what
the zero state is. But if we run with unused-macros I guess its even
uglier to try and mark it with unused attribute.

Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>

> @@ -175,7 +174,7 @@ int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
> return -ENODEV;
> }
>
> - /* State either UNREGISTERED or NEW */
> + /* State either UNREGISTERED or zero */
> xdp_rxq_info_init(xdp_rxq);
> xdp_rxq->dev = dev;
> xdp_rxq->queue_index = queue_index;
> --
> 1.8.3.1
>