Re: [PATCH] net/ring: Set mbuf->port for received packets

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

On 6/19/2024 7:48 AM, Morten Brørup wrote:
>> From: Sriram Yagnaraman [mailto:sriram.yagnaraman@ericsson.com]
>>
>> Hi Morten,
>>
>>> From: Morten Brørup <mb@smartsharesystems.com>
>>>
>>>> From: Sriram Yagnaraman [mailto:sriram.yagnaraman@ericsson.com]
>>>>
>>>> When using ring based ethdev, mbuf->port is not set on received packets.
>>>>
>>>> For applications that use the mbuf->port to identify the incoming
>>>> port, especially when eventdev RX adapter pulls the packet on a
>>>> different core and the application running on a worker core has no
>>>> clue on the incoming port. This change adds some cycles at receive, to
>>>> set the port of course.
>>>
>>> I agree that the mbuf->port field must be set before returning from
>>> rte_eth_rx_burst().
>>>
>>> I'm not aware how applications use the ring based ethdev, so I might be
>>> asking silly questions...
>>>
>>> How about all the other mbuf fields normally set by the PMD before
>>> returning from rte_eth_rx_burst()?
>>>
>>> Is the enqueueing core supposed to set them?
>>
>> I am integrating a couple of existing DPDK applications, and they use
>> rte_eth_* API between them today. To keep the API consistent, and not make too
>> many changes in the applications themselves, net_ring seems to be the best
>> option. If someone has a better idea, I would love to hear.
>>
>> There are no "HW" offloads when using net_ring, and IIUC there are no HW
>> related fields that can be set at rx_burst.
>> So, apart from port field, I didn't see much else that needed to be set.
>>
>>>
>>> Or if the ring is only used for queueing packets originally received (at a
>>> physical port) by the enqueueing core, why not keep the mbuf->port value
>>> from the original reception?
>>
>> In my case the enqueuing application originates the flow from SW, so the
>> rte_mbuf does not come from a NIC.
> 
> Thank you for the explanation.
> 
> Acked-by: Morten Brørup <mb@smartsharesystems.com>
> 

Acked-by: Ferruh Yigit <ferruh.yigit@amd.com>

Applied to dpdk-next-net/main, thanks.