[dpdk-dev] [PATCH v3 0/2] slow data path communication between DPDK port and Linux

[Ferruh Yigit]

On 3/16/2016 8:22 AM, Panu Matilainen wrote:
> On 03/16/2016 10:19 AM, Ferruh Yigit wrote:
>> On 3/16/2016 7:26 AM, Panu Matilainen wrote:
>>> On 03/14/2016 05:32 PM, Ferruh Yigit wrote:
>>>> On 3/9/2016 11:17 AM, Ferruh Yigit wrote:
>>>>> This patch sent to keep record of latest status of the work.
>>>>>
>>>>>
>>>>> This is slow data path communication implementation based on existing KNI.
>>>>>
>>>>> Difference is: librte_kni converted into a PMD, kdp kernel module is almost
>>>>> same except all control path functionality removed and some simplification done.
>>>>>
>>>>> Motivation is to simplify slow path data communication.
>>>>> Now any application can use this new PMD to send/get data to Linux kernel.
>>>>>
>>>>> PMD supports two communication methods:
>>>>>
>>>>> 1) KDP kernel module
>>>>> PMD initialization functions handles creating virtual interfaces (with help of
>>>>> kdp kernel module) and created FIFO. FIFO is used to share data between
>>>>> userspace and kernelspace. This is default method.
>>>>>
>>>>> 2) tun/tap module
>>>>> When KDP module is not inserted, PMD creates tap interface and transfers
>>>>> packets using tap interface.
>>>>>
>>>>> In long term this patch intends to replace the KNI and KNI will be
>>>>> depreciated.
>>>>>
>>>>
>>>> Self-NACK: Will work on another option that does not introduce new
>>>> kernel module.
>>>>
>>>
>>> Hmm, care to elaborate a bit? The second mode of this PMD already was
>>> free of external kernel modules. Do you mean you'll be just removing
>>> mode 1) from the PMD or looking at something completely different?
>>>
>>> Just thinking that tun/tap PMD sounds like a useful thing to have, I
>>> hope you're not abandoning that.
>>>
>>
>> It will be KNI PMD.
>> Plan is to have something like KDP, but with existing KNI kernel module.
>> There will be tun/tap support as fallback.
> 
> Hum, now I'm confused. I was under the impression everybody hated KNI 
> and wanted to get rid of it, and certainly not build future solutions on 
> top of it?
> 

We can't remove it.
We can't replace/improve it -you were one of the major opposition to this.
This doesn't leave more option other than using it.

There won't be any update in KNI kernel module, library + sample app
will be converted into PMD.

Regards,
ferruh