Re: [PATCH net-next] virtio-net: mark PM functions as __maybe_unused

[Jason Wang]

On 2017å07æ25æ 23:35, Arnd Bergmann wrote:
> After removing the reset function, the freeze and restore functions
> are now unused when CONFIG_PM_SLEEP is disabled:
>
> drivers/net/virtio_net.c:1881:12: error: 'virtnet_restore_up' defined but not used [-Werror=unused-function]
>   static int virtnet_restore_up(struct virtio_device *vdev)
> drivers/net/virtio_net.c:1859:13: error: 'virtnet_freeze_down' defined but not used [-Werror=unused-function]
>   static void virtnet_freeze_down(struct virtio_device *vdev)
>
> A more robust way to do this is to remove the #ifdef around the callers
> and instead mark them as __maybe_unused. The compiler will now just
> silently drop the unused code.
>
> Fixes: 4941d472bf95 ("virtio-net: do not reset during XDP set")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>   drivers/net/virtio_net.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index d4751ce23b4f..1902701e15a9 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2702,8 +2702,7 @@ static void virtnet_remove(struct virtio_device *vdev)
>   	free_netdev(vi->dev);
>   }
>   
> -#ifdef CONFIG_PM_SLEEP
> -static int virtnet_freeze(struct virtio_device *vdev)
> +static __maybe_unused int virtnet_freeze(struct virtio_device *vdev)
>   {
>   	struct virtnet_info *vi = vdev->priv;
>   
> @@ -2714,7 +2713,7 @@ static int virtnet_freeze(struct virtio_device *vdev)
>   	return 0;
>   }
>   
> -static int virtnet_restore(struct virtio_device *vdev)
> +static __maybe_unused int virtnet_restore(struct virtio_device *vdev)
>   {
>   	struct virtnet_info *vi = vdev->priv;
>   	int err;
> @@ -2730,7 +2729,6 @@ static int virtnet_restore(struct virtio_device *vdev)
>   
>   	return 0;
>   }
> -#endif
>   
>   static struct virtio_device_id id_table[] = {
>   	{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>