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

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

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?

> 
> Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>

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