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

[Ferruh Yigit <ferruh.yigit@intel.com>]

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@nfware.com>
> 
> <...>
>