On 30.11.2016 08:41, Gaohaifeng (A) wrote:
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); } }
Ah, probably the latter. Frankly, I don't have idea whether we should pass vectors= too. Do you? Michal