On 17-01-25 06:52 AM, Michael S. Tsirkin wrote: > On Tue, Jan 24, 2017 at 11:33:56PM -0800, Alexei Starovoitov wrote: >> On Tue, Jan 24, 2017 at 8:02 PM, John Fastabend >> <john.fastab...@gmail.com> wrote: >>> >>> Finally just to point out here are the drivers with XDP support on latest >>> net tree, >>> >>> mlx/mlx5 >>> mlx/mlx4 >>> qlogic/qede >>> netronome/nfp >>> virtio_net >>> >>> And here is the list of adjust header support, >>> >>> mlx/mlx4 >>> >> >> in net-next it's actually: >> yes: mlx4, mlx5 >> no: qede, nfp, virtio >> while nfp and virtio are working on it. >> >> xdp_adjust_head() is must have for load balancer, > > What amount of head space does it need? 70 bytes > to do vxlan kind of thing? > >> so the sooner it lands for virtio the easier it will be >> to develop xdp programs. Initially I expected >> e1k+xdp to be the base line for debugging and >> development of xdp programs, but since not everyone >> agreed on e1k the virtio+xdp filled in the gap. >> So without adjust_head in virtio I see very little use for it >> in our environment. >> It is a must have feature regardless of timing. >> I will backport whatever is necessary, but distros >> will stick with official releases and imo it's not great >> from xdp adoption point of view to have >> virtio driver lacking key features. > > If everyone can agree it's net-next material then I'm happy. >
Considering that the only support for adjust_head in net branch is in mlx4 and most drivers are aborting when programs get loaded with adjust_head support I am OK with applying the patch below to net and this series to net-next. https://patchwork.ozlabs.org/patch/707118/ diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 08327e005ccc..db761f37783e 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1677,6 +1677,11 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog) u16 xdp_qp = 0, curr_qp; int i, err; + if (prog && prog->xdp_adjust_head) { + netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n"); + return -EOPNOTSUPP; + } + if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) || virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6)) { netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n"); Thanks, John
