[Qemu-discuss] vhost-user eventfd problem

[梁永正]

I use the "vhost-user" mode in the qemu,and the backend is the dpdk-vhost.But 
when I use the eventfd_read(vq->kickfd,&val) function,It always return an 
error,and the val has always been 0.The kickfd is the eventfd that passing from 
qemu to vhost when the vring is set up and calling the 
vhost_user_set_vring_kick function.It should be a none-zero value when there 
are packets in the seding queue.The virtio-frontend should notify the backend 
then doing the dequeue operation.Does anyone know about this?I am looking 
forward to your reply.