[Qemu-devel] [PATCH 0/4] Introduce eventfd support for virtio-mmio

[Pavel Fedin]

 Hello!

 I have updated and successfully tested an old patch set introducing eventfd
support for virtio-mmio, enabling to use vhost-net with it:
https://lists.gnu.org/archive/html/qemu-devel/2014-02/msg00715.html
 I would like to upstream it, since virtio-mmio is still there. I know that
some of you consider it deprecated, however i believe this is not entirely
true. Because you can add it to machine models which are not supposed to
have PCI (like vexpress).
 An old patch set relied on additional "eventfd" option in order to disable
the support if not implemented in kernel. My version simply checks
kvm_eventfds_enabled() for this purpose, so backwards compatibility is much
better.
 I confirm that this solution significantly improves the network performance
even without using irqfd.

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia