[dpdk-users] Need help understanding rte_eth_dev_count

[Aniraj Kesavan <anirajkesavan@gmail.com>]

Hi,

I'm very new to dpdk and I'm trying to set it up on a cluster with the
following configuration:
DPDK - 16.07
Intel X710 2x10G Nics
Ubuntu 15.04

I could compile it, but when running sample applications such as
skeleton/basicfwd and testpmd, it fails saying the ports aren't detected.

I have done the following:
enabled 1G huge pages and mounted them under /dev/hugepages
ran dpdk-devbind.py on the interfaces after which the status shows:

Network devices using DPDK-compatible driver
============================================
0000:04:00.0 'Ethernet Controller X710 for 10GbE SFP+' drv=igb_uio unused=
0000:04:00.1 'Ethernet Controller X710 for 10GbE SFP+' drv=igb_uio unused=

While running gdb over the basicfwd application (run as sudo as it seemed
like a requirement), it seems like rte_eth_dev_count is returning 0. Even
the testpmd application is reporting no ports available. I have tried the
portmask option and tried to pass the interfaces as -w arguments too.

When I looked at rte_eth_dev_count, it's returning an unsigned static int
that is only updated by rte_eth_dev_allocate. Following the breadcrumbs, it
seemed like someone needed to invoke rte_eth_dev_register. I didn't see
that being called in the basicfwd example's codepath.

Can anyone tell me what usually causes rte_eth_dev_register to run and
update the port number? Or is there anything I might have missed in the
configuration that's causing the device to not show up when the library is
looking for it.



Thanks,
Aniraj



-- 
Aniraj Kesavan

MS CS '15-'17,
University Of Utah
CS '08-'12,
Govt. Model Engineering College
alternate e-mail:anirajkalathel@gmail.com
http://www.cs.utah.edu/~aniraj/