[dpdk-dev] [PATCH v2 1/5] kni: add API to set link status on kernel interface

[Dan Gora]

On Thu, Sep 27, 2018 at 8:35 AM Ferruh Yigit <ferruh.yigit at intel.com> wrote:
>
> On 9/26/2018 7:56 PM, Dan Gora wrote:
> > On Wed, Sep 26, 2018 at 1:42 PM, Ferruh Yigit <ferruh.yigit at intel.com> wrote:
> >>> There is nothing to "reflect" to the kernel interface, nor to apply to
> >>> the kernel interface.  This is exactly how every other kernel driver
> >>> works on link status changes.  There is no "netif_set_speed()'
> >>> function.  When a link status change occurs the kernel driver calls
> >>> netif_carrier_on/off() and prints a message like this one.
> >>
> >> I am not suggesting reflecting these into interface, I am just saying why do you
> >> print them?
> >
> > Because the information is useful and because every other Ethernet
> > driver does the same thing when the link status changes.
>
> It would be useful if it writes the values of virtual interface, but this API
> prints user input.
>
I'm sorry, Ferruh, I really don't understand what you are referring to
here.  What virtual interface are you talking about?

> The virtual interface may have different value, this API doesn't change anything
> related other than link status, so why print user provided value.

Again, because all this information is useful if the KNI interface is
reflecting the state of a real physical ethenet interface.  If the KNI
interface is not reflecting a real peice of hardware, the user can
continue not using this new API function or do something like set the
speed to 0.  This is what we get from ENA PMD drivers on amazon for
instance.  It's perfectly reasonable.

>
> Won't you think it will be confusing if the virtual interface values are
> different than what printed.

If what values are different from what?  I'm really confused as to
what use case you are referring to here.  Can you give a concrete
example?

> Or won't user will think API changed those values to printed one in interface?

again, what values?  Changed how?