+ Simei.

From: Dhamodaran Pandiyan <dhamodaran.it15@gmail.com>
Sent: Thursday, April 13, 2023 2:53 PM
To: Xing, Beilei <beilei.xing@intel.com>
Cc: David Marchand <david.marchand@redhat.com>; Jeff Guo <jia.guo@intel.com>; users@dpdk.org; Zhang, Helin <helin.zhang@intel.com>
Subject: Re: MAX_MBUF_SIZE causes queue configuration failure.

Hi Beilei,

We're using,

0000:5e:00.0 'Ethernet Controller X710 for 10GbE SFP+ 1572' drv=vfio-pci unused=i40e
0000:5e:00.1 'Ethernet Controller X710 for 10GbE SFP+ 1572' drv=vfio-pci unused=i40e

DPDK_VERSION=20.11

Please let me know if you need any other information.

Thanks,

Dhamodaran P

On Wed, 12 Apr 2023 at 18:24, Xing, Beilei <beilei.xing@intel.com> wrote:

Hi,

Which DPDK version did you use?
As i40evf PMD has been deprecated for long time.

BR,
Beilei

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Wednesday, April 12, 2023 3:28 PM
> To: Dhamodaran Pandiyan <dhamodaran.it15@gmail.com>; Xing, Beilei
> <beilei.xing@intel.com>; Jeff Guo <jia.guo@intel.com>
> Cc: users@dpdk.org
> Subject: Re: MAX_MBUF_SIZE causes queue configuration failure.
>
> Hello,
>
> On Wed, Apr 12, 2023 at 8:59 AM Dhamodaran Pandiyan
> <dhamodaran.it15@gmail.com> wrote:
> >
> > When I set the value to MAX_MBUF_SIZE as less than 16256, all the
> initialization went through fine and the application was online.
> >
> > But when I increase the MAX_MBUF_SIZE to more than 16256 like 16257,
> 17000, or 18000, I get the attached log error which shows an issue in
> configuring the virtual queues for the NIC.
> >
> > Log Snip:
> > i40evf_configure_vsi_queues(): Failed to execute command of
> > VIRTCHNL_OP_CONFIG_VSI_QUEUES
> > i40evf_dev_start(): configure queues failed
>
> Added net/i40e driver maintainers.
>
> This error indicates a failure either when sending a message to the PF driver, or
> that the PF driver refused to configure this VF with the passed parameters.
> Assuming you are using the PF i40e driver, I tracked this message handling to
> find that buffer size is limited (the exact limit is not clear to me) probably due
> to some hw limitations.
>
> See:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/
> net/ethernet/intel/i40e/i40e_virtchnl_pf.c#n4088
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/
> net/ethernet/intel/i40e/i40e_virtchnl_pf.c#n2371
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/
> net/ethernet/intel/i40e/i40e_virtchnl_pf.c#n714
>
> /* max pkt. length validation */
> if (info->max_pkt_size >= (16 * 1024) || info->max_pkt_size < 64) {
>     ret = -EINVAL;
>     goto error_param;
> }
>
> I'll let net/i40e reply with better details/explanations.
>
>
> > MTU size for port id:  is: 9000
> > Failed to start the fast pkt for port_id : 1Ret: -1
> >
> > Some Observations:
> > 1. Thought memory availability was an issue, so provided 10x more memory
> and allocated 10x huge pages than required, still noticed the same issue.
> > 2. Got to know MTU size also plays a role in deciding the mbuf_size, so tried
> running app with MTU of less value, but still issue persists.
> >
> > Please someone enlighten me on what is happening here.
>
>
>
> --
> David Marchand