diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 5dc34653274ae3655cf2ba97ab9c8dce9e8a2632..c42e9c30513417815ccc72a47ed298b11c0d5211 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -351,6 +351,15 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, return r; } +static bool vhost_exceeds_maxpend(struct vhost_net *net) +{ + struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; + struct vhost_virtqueue *vq = &nvq->vq; + + return (nvq->upend_idx + vq->num - VHOST_MAX_PEND) % UIO_MAXIOV + == nvq->done_idx; +} + /* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_tx(struct vhost_net *net) @@ -394,8 +403,7 @@ static void handle_tx(struct vhost_net *net) /* If more outstanding DMAs, queue the work. * Handle upend_idx wrap around */ - if (unlikely((nvq->upend_idx + vq->num - VHOST_MAX_PEND) - % UIO_MAXIOV == nvq->done_idx)) + if (unlikely(vhost_exceeds_maxpend(net))) break; head = vhost_net_tx_get_vq_desc(net, vq, vq->iov, @@ -454,6 +462,16 @@ static void handle_tx(struct vhost_net *net) msg.msg_control = NULL; ubufs = NULL; } + + total_len += len; + if (total_len < VHOST_NET_WEIGHT && + !vhost_vq_avail_empty(&net->dev, vq) && + likely(!vhost_exceeds_maxpend(net))) { + msg.msg_flags |= MSG_MORE; + } else { + msg.msg_flags &= ~MSG_MORE; + } + /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { @@ -472,7 +490,6 @@ static void handle_tx(struct vhost_net *net) vhost_add_used_and_signal(&net->dev, vq, head, 0); else vhost_zerocopy_signal_used(net, vq); - total_len += len; vhost_net_tx_packet(net); if (unlikely(total_len >= VHOST_NET_WEIGHT)) { vhost_poll_queue(&vq->poll);