Re: [RFC v1] virtio/vsock: add two more queues for datagram types

[Stefano Garzarella <sgarzare@redhat.com>]

On Thu, Jun 10, 2021 at 12:14:24AM +0000, Jiang Wang wrote:
>Datagram sockets are connectionless and unreliable.
>The sender does not know the capacity of the receiver
>and may send more packets than the receiver can handle.
>
>Add two more dedicate virtqueues for datagram sockets,
>so that it will not unfairly steal resources from
>stream and future connection-oriented sockets.
>
>The virtio spec patch is here:
>https://www.spinics.net/lists/linux-virtualization/msg50027.html
>
>Here is the link for the linux kernel git repo with patches
>to support dgram sockets:
>https://github.com/Jiang1155/linux/tree/vsock-dgram-v1
>
>Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
>---
> configure                                     | 13 +++++++++++++
> hw/virtio/vhost-vsock-common.c                | 11 ++++++++++-
> hw/virtio/vhost-vsock.c                       |  8 +++++---
> include/hw/virtio/vhost-vsock-common.h        | 10 +++++++++-
> include/standard-headers/linux/virtio_vsock.h |  3 +++
> meson.build                                   |  1 +
> 6 files changed, 41 insertions(+), 5 deletions(-)
>
>diff --git a/configure b/configure
>index 9f016b06b5..6455b283a5 100755
>--- a/configure
>+++ b/configure
>@@ -343,6 +343,7 @@ vhost_net="$default_feature"
> vhost_crypto="$default_feature"
> vhost_scsi="$default_feature"
> vhost_vsock="$default_feature"
>+vhost_vsock_dgram="no"
> vhost_user="no"
> vhost_user_blk_server="auto"
> vhost_user_fs="$default_feature"
>@@ -1272,6 +1273,10 @@ for opt do
>   ;;
>   --enable-vhost-vsock) vhost_vsock="yes"
>   ;;
>+  --disable-vhost-vsock-dgram) vhost_vsock_dgram="no"
>+  ;;
>+  --enable-vhost-vsock-dgram) vhost_vsock_dgram="yes"
>+  ;;

I don't think we should add a configuration option to enable/disable the 
dgram support at build time.

I think we should do it at runtime looking at the features negiotated.

Take a look at virtio_net_set_multiqueue().

Thanks,
Stefano