[dpdk-dev] newbie dpdk linux interfaces clarification

[Bruce Richardson]

On Mon, Sep 28, 2015 at 09:12:36PM +0100, Pedro Sousa wrote:
> Hi all,
> 
> I'm looking at dpdk the first time, so I would like someone could clarify
> me a little more about it.
> 
> I'm using a KVM Virtualized Guest that runs CentOS 7.1. I'm using SRIOV
> with bnx2x driver. When I bind my interface, as you can see below, to DPKD
> Driver igb_uio, I lose the interface control in linux.
> 
> My question is:
> 
> - Can use it normally on the operating system and how this is done?

Unfortunately not. An interface is either being used by the operating system
or by userspace (DPDK). It cannot be used by both at the same time. 

> 
> - Can I use it only on my app? And if so, how do I bind an ip from this
> dpdk interface to my app?

An IP address implies the presence of an IP stack. The DPDK libraries work
just on ethernet frames, and it's up to your app to provide an IP stack, and
therefore an IP address if it needs one.

Hope this clarifies things a bit for you.

Regards,
/Bruce

> 
> 
> *# ./dpdk_nic_bind.py --status*
> 
> *Network devices using DPDK-compatible driver*
> *============================================*
> *0000:00:08.0 'NetXtreme II BCM57810 10 Gigabit Ethernet Virtual Function'
> drv=igb_uio unused=vfio-pci,uio_pci_generic*
> 
> *Network devices using kernel driver*
> *===================================*
> *0000:00:07.0 'NetXtreme II BCM57810 10 Gigabit Ethernet Virtual Function'
> if=ens7 drv=bnx2x unused=igb_uio,vfio-pci,uio_pci_generic *Active**
> 
> 
> Thank you,
> Pedro Sousa