vhost/vsock: cleanup removing len variable

We can increment `total_len` directly and remove `len` since it
is no longer used for vhost_add_used().

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20211122163525.294024-3-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

Author: stefano-garzarella

drivers/vhost/vsock.c

@@ -511,8 +511,6 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
 
 	vhost_disable_notify(&vsock->dev, vq);
 	do {
-		u32 len;
-
 		if (!vhost_vsock_more_replies(vsock)) {
 			/* Stop tx until the device processes already
 			 * pending replies.  Leave tx virtqueue
@@ -540,7 +538,7 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
 			continue;
 		}
 
-		len = pkt->len;
+		total_len += sizeof(pkt->hdr) + pkt->len;
 
 		/* Deliver to monitoring devices all received packets */
 		virtio_transport_deliver_tap_pkt(pkt);
@@ -553,9 +551,7 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
 		else
 			virtio_transport_free_pkt(pkt);
 
-		len += sizeof(pkt->hdr);
 		vhost_add_used(vq, head, 0);
-		total_len += len;
 		added = true;
 	} while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));