[dpdk-stable] [PATCH 1/3] net/virtio: add initial RSS support

[Maxime Coquelin]

On 9/10/21 2:58 PM, Andrew Rybchenko wrote:
> On 9/10/21 2:44 PM, Maxime Coquelin wrote:
>> Thanks for the review!
>>
>> On 9/10/21 12:06 PM, Andrew Rybchenko wrote:
>>> On 9/10/21 12:17 PM, Maxime Coquelin wrote:
>>>>
>>> I've failed to find F_RSS definion in virtio spec.
>>> Could you share the reference, please.
>>>
>>> Without the sepc it is almost impossible to review the code.
>>
>> Sorry, I forgot to add the link, you can find it on the Virtio-spec
>> github master branch:
>>
>> https://github.com/oasis-tcs/virtio-spec/blob/master/content.tex
>>
>> For readability, I would suggest you to clone it and build the HTML or
>> PDF versions.
> 
> Many thanks.
> 
>>>> diff --git a/doc/guides/nics/features/virtio.ini b/doc/guides/nics/features/virtio.ini
>>>> index 48f6f393b1..883dd1426c 100644
>>>> --- a/doc/guides/nics/features/virtio.ini
>>>> +++ b/doc/guides/nics/features/virtio.ini
>>>> @@ -14,6 +14,8 @@ Promiscuous mode     = Y
>>>>  Allmulticast mode    = Y
>>>>  Unicast MAC filter   = Y
>>>>  Multicast MAC filter = Y
>>>
>>> I'd say that
>>> RSS has                = P
>>> should be added here.
>>
>> OK, as I mentionned in the cover letter, I was not sure becasue the doc
>> says "RSS hash" uses DEV_RX_OFFLOAD_RSS_HASH and provides mbuf.rss,
>> which this patch does not since it does not support (yet)
>> VIRTIO_NET_F_HASH_REPORT.
>> http://doc.dpdk.org/guides/nics/features.html#rss-hash
> 
> Yes, I've seen question in cover letter. It is some kind of gap
> in features to claim overall RSS support - just hashing and
> distribution across queues without hash forwarding to user.
> The item definition covers both generic support and offload to
> deliver RSS hash. That's why I suggest P (partial).

Ok, got it!

Thanks,
Maxime

>> I can try to add VIRTIO_NET_F_HASH_REPORT in v2, so that we can set RSS
>> hash = Y without any doubts :)
>>
>> Regards,
>> Maxime
>>
>