This patch improves the guest receive performance from
host. On the handle_tx side, we poll the sock receive
queue at the same time. handle_rx do that in the same way.
we set the poll-us=100 us and use the iperf3 to test
its throughput. The iperf3 command is shown as below.
iperf3 -s -D
iperf3 -c 192.168.1.100 -i 1 -P 10 -t 10 -M 1400 --bandwidth 100000M
* With the patch: 21.1 Gbits/sec
* Without the patch: 12.7 Gbits/sec
Signed-off-by: Tonghao Zhang <zhangtonghao@xxxxxxxxxxxxxxx>
---
drivers/vhost/net.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index e7cf7d2..9364ede 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -429,22 +429,43 @@ static int vhost_net_enable_vq(struct vhost_net *n,
return vhost_poll_start(poll, sock->file);
}
+static int sk_has_rx_data(struct sock *sk);
+
static int vhost_net_tx_get_vq_desc(struct vhost_net *net,
struct vhost_virtqueue *vq,
struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num)
{
unsigned long uninitialized_var(endtime);
+ struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_RX];
+ struct vhost_virtqueue *rvq = &nvq->vq;
+ struct socket *sock = rvq->private_data;
+
int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
out_num, in_num, NULL, NULL);
if (r == vq->num && vq->busyloop_timeout) {
+ mutex_lock_nested(&rvq->mutex, 1);
+
+ vhost_disable_notify(&net->dev, rvq);
+
preempt_disable();
endtime = busy_clock() + vq->busyloop_timeout;
while (vhost_can_busy_poll(vq->dev, endtime) &&
+ !(sock && sk_has_rx_data(sock->sk)) &&
vhost_vq_avail_empty(vq->dev, vq))
cpu_relax();
preempt_enable();
+
+ if (sock && sk_has_rx_data(sock->sk))
+ vhost_poll_queue(&rvq->poll);
+ else if (unlikely(vhost_enable_notify(&net->dev, rvq))) {
+ vhost_disable_notify(&net->dev, rvq);
+ vhost_poll_queue(&rvq->poll);
+ }
+
+ mutex_unlock(&rvq->mutex);
+
r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
out_num, in_num, NULL, NULL);
}
--
1.8.3.1
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
