Re: [PATCH net-next v2 08/14] virtio_net: auto release xdp shinfo

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Apr 18, 2023 at 2:53 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote:
>
> virtnet_build_xdp_buff_mrg() and virtnet_xdp_handler() auto
> release xdp shinfo then the caller no need to careful the xdp shinfo.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/virtio_net.c | 29 +++++++++++++++++------------
>  1 file changed, 17 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index e2eade87d2d4..266c1670beda 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -834,7 +834,7 @@ static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp,
>                 xdpf = xdp_convert_buff_to_frame(xdp);
>                 if (unlikely(!xdpf)) {
>                         netdev_dbg(dev, "convert buff to frame failed for xdp\n");
> -                       return VIRTNET_XDP_RES_DROP;
> +                       goto drop;
>                 }
>
>                 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0);
> @@ -842,7 +842,7 @@ static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp,
>                         xdp_return_frame_rx_napi(xdpf);
>                 } else if (unlikely(err < 0)) {
>                         trace_xdp_exception(dev, xdp_prog, act);
> -                       return VIRTNET_XDP_RES_DROP;
> +                       goto drop;
>                 }
>
>                 *xdp_xmit |= VIRTIO_XDP_TX;
> @@ -852,7 +852,7 @@ static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp,
>                 stats->xdp_redirects++;
>                 err = xdp_do_redirect(dev, xdp, xdp_prog);
>                 if (err)
> -                       return VIRTNET_XDP_RES_DROP;
> +                       goto drop;
>
>                 *xdp_xmit |= VIRTIO_XDP_REDIR;
>                 return VIRTNET_XDP_RES_CONSUMED;
> @@ -864,8 +864,12 @@ static int virtnet_xdp_handler(struct bpf_prog *xdp_prog, struct xdp_buff *xdp,
>                 trace_xdp_exception(dev, xdp_prog, act);
>                 fallthrough;
>         case XDP_DROP:
> -               return VIRTNET_XDP_RES_DROP;
> +               break;
>         }
> +
> +drop:
> +       put_xdp_frags(xdp);
> +       return VIRTNET_XDP_RES_DROP;
>  }

Patch looks correct but we end up some inconsistency here.

frags are automatically released.

but the page still needs to be freed by the caller?

Thanks


>
>  static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
> @@ -1201,7 +1205,7 @@ static int virtnet_build_xdp_buff_mrg(struct net_device *dev,
>                                  dev->name, *num_buf,
>                                  virtio16_to_cpu(vi->vdev, hdr->num_buffers));
>                         dev->stats.rx_length_errors++;
> -                       return -EINVAL;
> +                       goto err;
>                 }
>
>                 stats->bytes += len;
> @@ -1220,7 +1224,7 @@ static int virtnet_build_xdp_buff_mrg(struct net_device *dev,
>                         pr_debug("%s: rx error: len %u exceeds truesize %lu\n",
>                                  dev->name, len, (unsigned long)(truesize - room));
>                         dev->stats.rx_length_errors++;
> -                       return -EINVAL;
> +                       goto err;
>                 }
>
>                 frag = &shinfo->frags[shinfo->nr_frags++];
> @@ -1235,6 +1239,10 @@ static int virtnet_build_xdp_buff_mrg(struct net_device *dev,
>
>         *xdp_frags_truesize = xdp_frags_truesz;
>         return 0;
> +
> +err:
> +       put_xdp_frags(xdp);
> +       return -EINVAL;
>  }
>
>  static void *mergeable_xdp_prepare(struct virtnet_info *vi,
> @@ -1364,7 +1372,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
>                 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_frags;
> +                       goto err_xdp;
>
>                 act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);
>
> @@ -1372,7 +1380,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
>                 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_frags;
> +                               goto err_xdp;
>
>                         rcu_read_unlock();
>                         return head_skb;
> @@ -1382,11 +1390,8 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
>                         goto xdp_xmit;
>
>                 case VIRTNET_XDP_RES_DROP:
> -                       break;
> +                       goto err_xdp;
>                 }
> -err_xdp_frags:
> -               put_xdp_frags(&xdp);
> -               goto err_xdp;
>         }
>         rcu_read_unlock();
>
> --
> 2.32.0.3.g01195cf9f
>

_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization




[Index of Archives]     [KVM Development]     [Libvirt Development]     [Libvirt Users]     [CentOS Virtualization]     [Netdev]     [Ethernet Bridging]     [Linux Wireless]     [Kernel Newbies]     [Security]     [Linux for Hams]     [Netfilter]     [Bugtraq]     [Yosemite Forum]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux Admin]     [Samba]

  Powered by Linux