Re: [dpdk-dev] [PATCH 1/2] ethdev: announce flow API action PORT_ID changes

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 8/2/21 6:49 PM, Ilya Maximets wrote:
> On 8/1/21 12:22 PM, Andrew Rybchenko wrote:
>> By its very name, action PORT_ID means that packets hit an ethdev with the
>> given DPDK port ID. At least the current comments don't state the opposite.
>> That said, since port representors had been adopted, applications like OvS
>> have been misusing the action. They misread its purpose as sending packets
>> to the opposite end of the "wire" plugged to the given ethdev, for example,
>> redirecting packets to the VF itself rather than to its representor ethdev.
>> Another example: OvS relies on this action with the admin PF's ethdev port
>> ID specified in it in order to send offloaded packets to the physical port.
> 
> Hi, Andrew.  The deprecation notice itself looks OK to me.  But I'd suggest
> to avoid words like "misuse" and "misread" in the commit message, because I
> don't think that it's correct.  Since documentation is ambiguous, different
> people might interpret it differently.  And also, implementation in DPDK
> matches with the way how OVS uses the API, otherwise offloading in OVS would
> just not work.  So, OVS uses this API in a way as it is implemented in DPDK.
> If the definition of a DPDK API allows interpretations that doesn't match with
> the implementation inside the DPDK itself, that's not a fault of the external
> application. And this can not be labeled as "misuse"/"misread".  Let's not
> create a precedent.

Yes, I agree. I'll send v2 tomorrow.

Thanks for feedback,
Andrew.