Re: [RFC 0/8] virtio,vhost: Add VIRTIO_F_NOTIFICATION_DATA support

[Xinying Yu]

Of course,  I am glad to do.  And I need to clarify that our use case only support VIRTIO_F_NOTIFICATION_DATA  transport feature on DPDK vDPA framework which the backend type is NET_CLIENT_DRIVER_VHOST_USER and use user_feature_bits. So the new feature add on vdpa_feature_bits  will not under verified in our case.  Not sure this meets your expectations?

One more thing, I would ask how do  I get the full series patch? Do I copy the RFC line by line from this link[1]?

Thanks,

Xinying

[1] https://lists.nongnu.org/archive/html/qemu-devel/2024-03/msg00090.html

---

From: Eugenio Perez Martin <eperezma@redhat.com>
Sent: Saturday, March 2, 2024 4:32 AM
To: Wentao Jia <wentao.jia@nephogine.com>; Rick Zhong <zhaoyong.zhong@nephogine.com>; Xinying Yu <xinying.yu@nephogine.com>
Cc: Jonah Palmer <jonah.palmer@oracle.com>; qemu-devel@nongnu.org <qemu-devel@nongnu.org>; mst@redhat.com <mst@redhat.com>; jasowang@redhat.com <jasowang@redhat.com>; si-wei.liu@oracle.com <si-wei.liu@oracle.com>; boris.ostrovsky@oracle.com <boris.ostrovsky@oracle.com>; raphael@enfabrica.net <raphael@enfabrica.net>; kwolf@redhat.com <kwolf@redhat.com>; hreitz@redhat.com <hreitz@redhat.com>; pasic@linux.ibm.com <pasic@linux.ibm.com>; borntraeger@linux.ibm.com <borntraeger@linux.ibm.com>; farman@linux.ibm.com <farman@linux.ibm.com>; thuth@redhat.com <thuth@redhat.com>; richard.henderson@linaro.org <richard.henderson@linaro.org>; david@redhat.com <david@redhat.com>; iii@linux.ibm.com <iii@linux.ibm.com>; cohuck@redhat.com <cohuck@redhat.com>; pbonzini@redhat.com <pbonzini@redhat.com>; fam@euphon.net <fam@euphon.net>; stefanha@redhat.com <stefanha@redhat.com>; qemu-block@nongnu.org <qemu-block@nongnu.org>; qemu-s390x@nongnu.org <qemu-s390x@nongnu.org>; virtio-fs@lists.linux.dev <virtio-fs@lists.linux.dev>
Subject: Re: [RFC 0/8] virtio,vhost: Add VIRTIO_F_NOTIFICATION_DATA support

 

Hi Wentao / Rick / Xinying Yu,

Would it work for you to test this series on your use cases, so we
make sure everything works as expected?

Thanks!

On Fri, Mar 1, 2024 at 2:44 PM Jonah Palmer <jonah.palmer@oracle.com> wrote:
>
> The goal of these patches are to add support to a variety of virtio and
> vhost devices for the VIRTIO_F_NOTIFICATION_DATA transport feature. This
> feature indicates that a driver will pass extra data (instead of just a
> virtqueue's index) when notifying the corresponding device.
>
> The data passed in by the driver when this feature is enabled varies in
> format depending on if the device is using a split or packed virtqueue
> layout:
>
>  Split VQ
>   - Upper 16 bits: last_avail_idx
>   - Lower 16 bits: virtqueue index
>
>  Packed VQ
>   - Upper 16 bits: 1-bit wrap counter & 15-bit last_avail_idx
>   - Lower 16 bits: virtqueue index
>
> Also, due to the limitations of ioeventfd not being able to carry the
> extra provided by the driver, ioeventfd is left disabled for any devices
> using this feature.
>
> A significant aspect of this effort has been to maintain compatibility
> across different backends. As such, the feature is offered by backend
> devices only when supported, with fallback mechanisms where backend
> support is absent.
>

Hi Wentao,