[dpdk-users] DPDK device name

[dpdk-users] DPDK device name

[Filip Janiszewski]

Hi,

Is there any mapping between the port names I see while using 'ifconfig'
and the port numbers I use normally to handle NIC ports? In other words,
is there a way to identify which ports number corresponds to a given
linux interface name?

Thanks

-- 
BR, Filip
+48 666 369 823

Re: [dpdk-users] DPDK device name

[Rosen, Rami]

Hi Flip,
I assume that by "port numbers" you mean the PCI bus id (BDF)
that is used by DPDK (for bind, for example).

You can fetch the bus id for a netdevice named "eth0" by
ethtool -i eth0 | grep bus-info
bus-info: 0000:01:00.0

If you mean the internal port number (starting from 0 for the first port, and so on) inside DPDK, then there is no 
mapping between the interface name (as seen by ifconfig) and the internal DPDK port number.

Regards,
Rami  Rosen



-----Original Message-----
From: users [mailto:users-bounces@dpdk.org] On Behalf Of Filip Janiszewski
Sent: Thursday, April 19, 2018 09:13
To: users@dpdk.org
Subject: [dpdk-users] DPDK device name

Hi,

Is there any mapping between the port names I see while using 'ifconfig'
and the port numbers I use normally to handle NIC ports? In other words, is there a way to identify which ports number corresponds to a given linux interface name?

Thanks

--
BR, Filip
+48 666 369 823

Re: [dpdk-users] DPDK device name

[Stephen Hemminger]

On Thu, 19 Apr 2018 07:15:07 +0000
"Rosen, Rami" <rami.rosen@intel.com> wrote:

> Hi Flip,
> I assume that by "port numbers" you mean the PCI bus id (BDF)
> that is used by DPDK (for bind, for example).
> 
> You can fetch the bus id for a netdevice named "eth0" by
> ethtool -i eth0 | grep bus-info
> bus-info: 0000:01:00.0
> 
> If you mean the internal port number (starting from 0 for the first port, and so on) inside DPDK, then there is no 
> mapping between the interface name (as seen by ifconfig) and the internal DPDK port number.
> 
> Regards,
> Rami  Rosen
> 
> 
> 
> -----Original Message-----
> From: users [mailto:users-bounces@dpdk.org] On Behalf Of Filip Janiszewski
> Sent: Thursday, April 19, 2018 09:13
> To: users@dpdk.org
> Subject: [dpdk-users] DPDK device name
> 
> Hi,
> 
> Is there any mapping between the port names I see while using 'ifconfig'
> and the port numbers I use normally to handle NIC ports? In other words, is there a way to identify which ports number corresponds to a given linux interface name?
> 
> Thanks
> 
> --
> BR, Filip
> +48 666 369 823

Short answer No.

Long answer.
DPDK devices can be virtual, shared, or connected to a bus. Most devices are connected
to Pci bus and must be unbound and rebound to use DPDK userspace i/o. The PCI address
is the underlying value used by DPDK. You can find the value via sysfs 
/sys/class/net/ethN/device (reliable) or ethtool (works for most devices). But once
device is unbound from the kernel driver, it no longer has a kernel assigned name.

DPDK port numbers are assigned in order, so if multiple devices are used by DPDK
they are seen in lexical order as PCI scanning occurs.

It is also possible to use KNI to get a kernel network interface for a DPDK
port.

Lots of options.