On Tue, Apr 18, 2023 at 2:53 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote:
>
> The purpose of this patch is to simplify the receive_mergeable().
> Separate all the logic of XDP into a function.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
Thanks
> ---
> drivers/net/virtio_net.c | 100 ++++++++++++++++++++++++---------------
> 1 file changed, 61 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 266c1670beda..42e9927e316b 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -1319,6 +1319,63 @@ static void *mergeable_xdp_prepare(struct virtnet_info *vi,
> return page_address(*page) + VIRTIO_XDP_HEADROOM;
> }
>
> +static struct sk_buff *receive_mergeable_xdp(struct net_device *dev,
> + struct virtnet_info *vi,
> + struct receive_queue *rq,
> + struct bpf_prog *xdp_prog,
> + void *buf,
> + void *ctx,
> + unsigned int len,
> + unsigned int *xdp_xmit,
> + struct virtnet_rq_stats *stats)
> +{
> + struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
> + int num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
> + struct page *page = virt_to_head_page(buf);
> + int offset = buf - page_address(page);
> + unsigned int xdp_frags_truesz = 0;
> + struct sk_buff *head_skb;
> + unsigned int frame_sz;
> + struct xdp_buff xdp;
> + void *data;
> + u32 act;
> + int err;
> +
> + data = mergeable_xdp_prepare(vi, rq, xdp_prog, ctx, &frame_sz, &num_buf, &page,
> + offset, &len, hdr);
> + if (unlikely(!data))
> + goto err_xdp;
> +
> + err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,
> + &num_buf, &xdp_frags_truesz, stats);
> + if (unlikely(err))
> + goto err_xdp;
> +
> + act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
> +
> + switch (act) {
> + case VIRTNET_XDP_RES_PASS:
> + head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
> + if (unlikely(!head_skb))
> + goto err_xdp;
> + return head_skb;
> +
> + case VIRTNET_XDP_RES_CONSUMED:
> + return NULL;
> +
> + case VIRTNET_XDP_RES_DROP:
> + break;
> + }
> +
> +err_xdp:
> + put_page(page);
> + mergeable_buf_free(rq, num_buf, dev, stats);
> +
> + stats->xdp_drops++;
> + stats->drops++;
> + return NULL;
> +}
> +
> static struct sk_buff *receive_mergeable(struct net_device *dev,
> struct virtnet_info *vi,
> struct receive_queue *rq,
> @@ -1338,8 +1395,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
> unsigned int headroom = mergeable_ctx_to_headroom(ctx);
> unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;
> unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);
> - unsigned int frame_sz;
> - int err;
>
> head_skb = NULL;
> stats->bytes += len - vi->hdr_len;
> @@ -1359,39 +1414,10 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
> rcu_read_lock();
> xdp_prog = rcu_dereference(rq->xdp_prog);
> if (xdp_prog) {
> - unsigned int xdp_frags_truesz = 0;
> - struct xdp_buff xdp;
> - void *data;
> - u32 act;
> -
> - data = mergeable_xdp_prepare(vi, rq, xdp_prog, ctx, &frame_sz,
> - &num_buf, &page, offset, &len, hdr);
> - if (unlikely(!data))
> - goto err_xdp;
> -
> - err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,
> - &num_buf, &xdp_frags_truesz, stats);
> - if (unlikely(err))
> - goto err_xdp;
> -
> - act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
> -
> - switch (act) {
> - case VIRTNET_XDP_RES_PASS:
> - head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);
> - if (unlikely(!head_skb))
> - goto err_xdp;
> -
> - rcu_read_unlock();
> - return head_skb;
> -
> - case VIRTNET_XDP_RES_CONSUMED:
> - rcu_read_unlock();
> - goto xdp_xmit;
> -
> - case VIRTNET_XDP_RES_DROP:
> - goto err_xdp;
> - }
> + head_skb = receive_mergeable_xdp(dev, vi, rq, xdp_prog, buf, ctx,
> + len, xdp_xmit, stats);
> + rcu_read_unlock();
> + return head_skb;
> }
> rcu_read_unlock();
>
> @@ -1461,9 +1487,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
> ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
> return head_skb;
>
> -err_xdp:
> - rcu_read_unlock();
> - stats->xdp_drops++;
> err_skb:
> put_page(page);
> mergeable_buf_free(rq, num_buf, dev, stats);
> @@ -1471,7 +1494,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
> err_buf:
> stats->drops++;
> dev_kfree_skb(head_skb);
> -xdp_xmit:
> return NULL;
> }
>
> --
> 2.32.0.3.g01195cf9f
>
