[dpdk-dev] [PATCH v2] kni: use kni_ethtool_ops only with unknown drivers

[Igor Ryzhov]

Hi Stephen,

I also do not see the point of the current implementation of ethtool
support.
That's why I sent this patch – it enables ethtool_ops for all devices,
independent of the underlying driver.
Right now only .get_link is supported, but I am thinking about
implementation of a larger set of functions, using req/resp queue, like
netdev_ops functions are working.

Regarding the KNI itself, we use it as Linux mirror of physical port for:
1. Port configuration from Linux – such functions as set_mac, change_mtu,
etc. And ethtool_ops will be used the same way.
2. Passing control-plane packets to Linux.

Can virtio user be used the same way, as a mirror of physical port?

Best regards,
Igor

On Sat, Dec 1, 2018 at 2:38 AM Stephen Hemminger <stephen at networkplumber.org>
wrote:

> On Fri, 30 Nov 2018 22:47:50 +0300
> Igor Ryzhov <iryzhov at nfware.com> wrote:
>
> > Current implementation of kni_ethtool_ops just uses corresponding
> > ethtool_ops function of underlying driver for all functions except for
> > .get_link. This commit sets kni->net_dev->ethtool_ops directly to the
> > ethtool_ops of the corresponding driver.
> >
> > For unknown drivers (all but ixgbe and i40e) we still use
> > kni_ethtool_ops with implemented .get_link function.
> >
> > Signed-off-by: Igor Ryzhov <iryzhov at nfware.com>
>
> Why does KNI still support ethtool which:
>   1. Only works on a subset of devices
>   2. Requires a 3rd implmentation of the HW device (Linux, DPDK, and KNI)
>
> Then again why does KNI exist at all? What is missing from virtio user
> which
> is faster anyway.
>