Re: [PATCH net-next v3 15/15] virtio_net: introduce virtnet_build_skb()

[Jason Wang <jasowang@xxxxxxxxxx>]

在 2023/4/23 18:57, Xuan Zhuo 写道:
> This logic is used in multiple places, now we separate it into
> a helper.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>


Acked-by: Jason Wang <jasowang@xxxxxxxxxx>

Thanks


> ---
>   drivers/net/virtio_net.c | 34 +++++++++++++++++++++-------------
>   1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 811cf1046df2..f768e683dadb 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -443,6 +443,22 @@ static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx)
>   	return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1);
>   }
>   
> +static struct sk_buff *virtnet_build_skb(void *buf, unsigned int buflen,
> +					 unsigned int headroom,
> +					 unsigned int len)
> +{
> +	struct sk_buff *skb;
> +
> +	skb = build_skb(buf, buflen);
> +	if (unlikely(!skb))
> +		return NULL;
> +
> +	skb_reserve(skb, headroom);
> +	skb_put(skb, len);
> +
> +	return skb;
> +}
> +
>   /* Called from bottom half context */
>   static struct sk_buff *page_to_skb(struct virtnet_info *vi,
>   				   struct receive_queue *rq,
> @@ -476,13 +492,10 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,
>   
>   	/* copy small packet so we can reuse these pages */
>   	if (!NET_IP_ALIGN && len > GOOD_COPY_LEN && tailroom >= shinfo_size) {
> -		skb = build_skb(buf, truesize);
> +		skb = virtnet_build_skb(buf, truesize, p - buf, len);
>   		if (unlikely(!skb))
>   			return NULL;
>   
> -		skb_reserve(skb, p - buf);
> -		skb_put(skb, len);
> -
>   		page = (struct page *)page->private;
>   		if (page)
>   			give_pages(rq, page);
> @@ -946,13 +959,10 @@ static struct sk_buff *receive_small_build_skb(struct virtnet_info *vi,
>   	buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
>   		SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
>   
> -	skb = build_skb(buf, buflen);
> -	if (!skb)
> +	skb = virtnet_build_skb(buf, buflen, headroom, len);
> +	if (unlikely(!skb))
>   		return NULL;
>   
> -	skb_reserve(skb, headroom);
> -	skb_put(skb, len);
> -
>   	buf += header_offset;
>   	memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
>   
> @@ -1028,12 +1038,10 @@ static struct sk_buff *receive_small_xdp(struct net_device *dev,
>   		goto err_xdp;
>   	}
>   
> -	skb = build_skb(buf, buflen);
> -	if (!skb)
> +	skb = virtnet_build_skb(buf, buflen, xdp.data - buf, len);
> +	if (unlikely(!skb))
>   		goto err;
>   
> -	skb_reserve(skb, xdp.data - buf);
> -	skb_put(skb, len);
>   	if (metasize)
>   		skb_metadata_set(skb, metasize);
>