Re: [PATCH net-next V2 11/11] vhost_net: batch submitting XDP buffers to underlayer sockets

From: Michael S. Tsirkin
Date: Thu Sep 13 2018 - 14:05:03 EST


On Wed, Sep 12, 2018 at 11:17:09AM +0800, Jason Wang wrote:
> +static void vhost_tx_batch(struct vhost_net *net,
> + struct vhost_net_virtqueue *nvq,
> + struct socket *sock,
> + struct msghdr *msghdr)
> +{
> + struct tun_msg_ctl ctl = {
> + .type = TUN_MSG_PTR,
> + .num = nvq->batched_xdp,
> + .ptr = nvq->xdp,
> + };
> + int err;
> +
> + if (nvq->batched_xdp == 0)
> + goto signal_used;
> +
> + msghdr->msg_control = &ctl;
> + err = sock->ops->sendmsg(sock, msghdr, 0);
> + if (unlikely(err < 0)) {
> + vq_err(&nvq->vq, "Fail to batch sending packets\n");
> + return;
> + }
> +
> +signal_used:
> + vhost_net_signal_used(nvq);
> + nvq->batched_xdp = 0;
> +}
> +

Given it's all tun-specific now, how about just exporting tap_sendmsg
and calling that? Will get rid of some indirection too.

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MST