[dpdk-dev] [PATCH v3] kni: rework rte_kni_update_link using ioctl

[Dan Gora]

My original patch to add this feature was basically the same thing as
this: setting the link status via a KNI ioctl. That method was
rejected after _much_ discussion and we eventually settled on the
currently implementation.

My original patch was here: Message-Id: <20180628225548.21885-1-dg at adax.com>

If you search for KNI and dg at adax.com in the DPDK devel list you
should be able to suss out the whole discussion that lead to the
current implementation.

thanks
dan

On Mon, Oct 14, 2019 at 1:17 PM Ferruh Yigit <ferruh.yigit at intel.com> wrote:
>
> On 10/14/2019 5:10 PM, Ferruh Yigit wrote:
> > On 9/25/2019 10:36 AM, Igor Ryzhov wrote:
> >> Current implementation doesn't allow us to update KNI carrier if the
> >> interface is not yet UP in kernel. It means that we can't use it in the
> >> same thread which is processing rte_kni_ops.config_network_if, which is
> >> very convenient, because it allows us to have correct carrier status
> >> of the interface right after we enabled it and we don't have to use any
> >> additional thread to track link status.
> >
> > Hi Igor,
> >
> > The existing thread tracks the link status of the physical device and reflects
> > the changes to the kni netdev, but the "struct rte_kni_ops"
> > (rte_kni_ops.config_network_if) works other way around, it captures (some)
> > requests to kni netdev and reflects them to the underlying physical device.
> > Even 'rte_kni_update_link()' updated to use ioctl, the thread still looks
> > required and this patch doesn't really changes that part.
> >
> > Also I am reluctant to extend the KNI ioctl interface when there is a generic
> > way to do that work.
> >
> > What is the use case of updating kni netdev carrier status when the interface is
> > down?
>
> btw, if the problem is status of the interface being 'no-carrier' by default,
> this can be changed by "carrier=on" parameter of the kni kernel module:
> "insmod ./build/kmod/rte_kni.ko carrier=on"
>
> >
> >>
> >> Signed-off-by: Igor Ryzhov <iryzhov at nfware.com>
> >
> > <...>
> >
>