Re: [Qemu-devel] [PATCH 0/4] ioeventfd support for virtio-mmio

[Shannon Zhao <zhaoshenglong@huawei.com>]

On 2014/11/4 20:47, Shannon Zhao wrote:
> Add host/guest notifiers support for virtio-mmio, so that qemu can
> enable vhost-net for kvm-arm.
> 
> Refer to the patches from Ying-Shiuan Pan
> https://lists.gnu.org/archive/html/qemu-devel/2014-02/msg00715.html
> 
> As vhost-net can improve the net performance by about 30%,
> so I think it's necessary to make virtio-mmio work with vhost-net
> on arm/arm64.
Hi,

Some virtio-net with virtio-mmio performance data on ARM added as followed:

Type of backend         bandwith(GBytes/sec) (From Host to Guest)
virtio-net              0.66
vhost-net               1.49
vhost-net with irqfd    2.01

Test cmd: ./iperf -c 192.168.0.2 -P 1 -i 10 -p 5001 -f G -t 60

>From this test data, vhost-net and irqfd have great improvement on performance.
So maybe it's necessary to enable ioeventfd make vhost-net work with
virtio-mmio on ARM/ARM64.

Look forward to your feedback :)

Thanks,
Shannon

> 
> Shannon Zhao (4):
>   virtio-mmio: introduce set_host_notifier()
>   virtio-mmio: introduce set_guest_notifiers
>   virtio-mmio: start ioeventfd when status gets DRIVER_OK
>   virtio-mmio: add a new property for ioeventfd
> 
>  hw/net/virtio-net.c        |    1 +
>  hw/virtio/virtio-mmio.c    |  176 ++++++++++++++++++++++++++++++++++++++++++++
>  include/hw/virtio/virtio.h |    1 +
>  3 files changed, 178 insertions(+), 0 deletions(-)
> 
> 
> 

-- 
Shannon