Hi ALL:

Recently I review the vhost-user hotplug codes, when attach a vhost-user nic with multiqueue, it seems that it doesn’t pass mq=on and vectors num to qemu.

Is there any special consideration or just a small mistake? Parts of codes:

qemuDomainAttachNetDevice(vhostfdSize is 0 when type is vhost-user)

qemuBuildNicDevStr:

             if (usingVirtio && vhostfdSize > 1) {

        if (net->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_CCW) {

            /* ccw provides a one to one relation of fds to queues and

             * does not support the vectors option

             */

            virBufferAddLit(&buf, ",mq=on");

        } else {

            /* As advised at http://www.linux-kvm.org/page/Multiqueue

             * we should add vectors=2*N+2 where N is the vhostfdSize

             */

            virBufferAsprintf(&buf, ",mq=on,vectors=%zu", 2 * vhostfdSize + 2);

        }

}

Thanks.

Haifeng Gao