Manage DPDK port capability via KNI

Manage DPDK port capability via KNI

[Tim Deng]

Hi,


I am wondering how could we manage a DPDK port offload capabilities,
e.g. if we want to disable TSO capability on a DPDK port, is it feasible
that we use ethtool to configure a KNI then the config will be sync to a DPDK port?


Thanks,
Tim

Re: Manage DPDK port capability via KNI

[Zhou, Danny]

You can do it but it will not sync with DPDK. In current KNI implementation, the devices'
I/O address spaces are mapped to both userspace DPDK and kenrelspace KNI, so one
can control the NIC device independently(using ethtool for KNI and ethdev APIs for DPDK)
without synchronization.

In theory, KNI should route all device control request from ethtool to DPDK. But unfortunately,
a short path is adopted at the moment due to DPDK reused lots of legacy kernel codes with BSD license.

> -----Original Message-----
> From: dev [mailto:dev-bounces-VfR2kkLFssw@public.gmane.org] On Behalf Of Tim Deng
> Sent: Wednesday, February 25, 2015 9:57 AM
> To: dev-VfR2kkLFssw@public.gmane.org
> Subject: [dpdk-dev] Manage DPDK port capability via KNI
> 
> Hi,
> 
> 
> I am wondering how could we manage a DPDK port offload capabilities,
> e.g. if we want to disable TSO capability on a DPDK port, is it feasible
> that we use ethtool to configure a KNI then the config will be sync to a DPDK port?
> 
> 
> Thanks,
> Tim

Re: Manage DPDK port capability via KNI

[Tim Deng]

Thanks Danny,
That means DPDK ports have to have dedicated control path other than KNI.


I originally got confused by the statement at http://dpdk.org/doc/guides/prog_guide/kernel_nic_interface.html:
"...Allows management of DPDK ports using standard Linux net tools such as ethtool, ifconfig and tcpdump."
Thanks,
Tim


At 2015-02-25 13:05:08, "Zhou, Danny" <danny.zhou@intel.com> wrote:
>You can do it but it will not sync with DPDK. In current KNI implementation, the devices'
>I/O address spaces are mapped to both userspace DPDK and kenrelspace KNI, so one
>can control the NIC device independently(using ethtool for KNI and ethdev APIs for DPDK)
>without synchronization.
>
>In theory, KNI should route all device control request from ethtool to DPDK. But unfortunately,
>a short path is adopted at the moment due to DPDK reused lots of legacy kernel codes with BSD license.
>
>> -----Original Message-----
>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Tim Deng
>> Sent: Wednesday, February 25, 2015 9:57 AM
>> To: dev@dpdk.org
>> Subject: [dpdk-dev] Manage DPDK port capability via KNI
>> 
>> Hi,
>> 
>> 
>> I am wondering how could we manage a DPDK port offload capabilities,
>> e.g. if we want to disable TSO capability on a DPDK port, is it feasible
>> that we use ethtool to configure a KNI then the config will be sync to a DPDK port?
>> 
>> 
>> Thanks,
>> Tim