[dpdk-dev] [RFC] testpmd: handle UFO packets

[Jason Wang]

On 2018年02月28日 22:53, Tan, Jianfeng wrote:
> Hi Jason,
>
>
> On 2/28/2018 10:10 PM, Jason Wang wrote:
>>
>>
>> On 2018年02月24日 17:35, Jianfeng Tan wrote:
>>> Mostly likely, we will make UFO as a kind of GSO engine.
>>>
>>> For short term, we can just call APIs in librte_ip_frag to fragment.
>>>
>>> To test:
>>>
>>> 1. start testpmd with two vhost port.
>>>   $ set fwd csum
>>>   $ start
>>>
>>> 2. start vm0 connected to vhost0;
>>>   $ ifconfig xxx 1.1.1.1/24 up
>>>   $ ethtool -K xxx ufo on
>>>
>>> 3. start vm1 connected to vhost1;
>>>   $ ifconfig xxx 1.1.1.2/24 up
>>>   $ ethtool -K xxx ufo on
>>>   $ (Fill a large file named 1.txt)
>>>   $ cat 1.txt | socat - udp-sendto:1.1.1.1:5000
>>
>> Just a reminder, UFO was completely removed upstream.
>>
>
> Thank you for the information.
>
> Saw the deprecation patch at Linux v4.16-rc3, wonder what "version+" 
> counts "merden kernels" in "modern kernels will no longer generate UFO 
> skbs"? 

git describe d9d30adf56777c402c0027c0e6ae21f17cc0a365
v4.12-11055-gd9d30ad

So I think any Linux version beyond 4.12 won't generate any UFO packets.

> And this is mostly for stock VMs with old kernels to help the 
> migration from kernel vswitch to user space vswitch.
>

Yes, testpmd may still see UFO packets for old kernels. Just a reminder 
in case you miss it.

(Btw, we plan to support UDP tunnel offload for virtio-net.)

> Will other OSes generate UFO packets, FreeBSD, Windows? Anyone can 
> provide such information?

I don't know about them.

Thanks.

>
> Thanks,
> Jianfeng
>
>