On Wed, Dec 7, 2016 at 9:22 PM, Stefan Hajnoczi [off-list ref] wrote:

On Wed, Dec 07, 2016 at 06:00:20PM +0800, Peng Tao wrote:

quoted

Signed-off-by: Peng Tao <redacted>
---
 net/vmw_vsock/virtio_transport.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 936d7ee..f88b6ed 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c

@@ -170,6 +170,41 @@ virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt)
      return len;
 }

+static int
+virtio_transport_cancel_pkt(struct vsock_sock *vsk)
+{
+     struct virtio_vsock *vsock;
+     struct virtio_vsock_pkt *pkt, *n;
+     int cnt = 0;
+     LIST_HEAD(freeme);
+
+     vsock = virtio_vsock_get();
+     if (!vsock) {
+             return -ENODEV;
+     }
+
+     if (pkt->reply)

pkt is uninitialized.  I guess this if statement should be deleted, you
already take care of counting reply packets below.

ah, sorry! I forgot to delete it after handling cnt below...

quoted

+             cnt++;
+
+     spin_lock_bh(&vsock->send_pkt_list_lock);
+     list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) {
+             if (pkt->vsk != vsk)
+                     continue;
+             list_move(&pkt->list, &freeme);
+     }
+     spin_unlock_bh(&vsock->send_pkt_list_lock);
+
+     list_for_each_entry_safe(pkt, n, &freeme, list) {
+             if (pkt->reply)
+                     cnt++;
+             list_del(&pkt->list);
+             virtio_transport_free_pkt(pkt);
+     }
+     atomic_sub(cnt, &vsock->queued_replies);

If we stopped rx because there were too many replies in flight then we
might be able to resume rx now:

/* Do we now have resources to resume rx processing? */
if (old_val >= virtqueue_get_vring_size(rx_vq) &&
    new_val < virtqueue_get_vring_size(rx_vq))
        queue_work(virtio_vsock_workqueue, &vsock->rx_work);

Thanks! I totally missed the resume part... I'll send an updated version later.

Cheers,
Tao