Re: [dpdk-dev] [PATCH v8 2/3] i40e: Add floating VEB support in i40e

[Bruce Richardson <bruce.richardson@intel.com>]

On Wed, May 25, 2016 at 01:28:05AM +0800, Zhe Tao wrote:
> This patch add the support for floating VEB in i40e.
> All the VFs VSIs can decide whether to connect to the legacy VEB/VEPA or
> the floating VEB. When connect to the floating VEB a new floating VEB is
> created. Now all the VFs need to connect to floating VEB or legacy VEB,
> cannot connect to both of them. The PF and VMDQ,FD VSIs still connect to
> the old legacy VEB/VEPA.
> 
> All the VEB/VEPA concepts are not specific for FVL, they are defined in the
> 802.1Qbg spec.
copy reference to patch 1.

> 
> Now the floating VEB feature is only avaiable in the specific version of FW.
Please list the firmware versions rather than making the reader read through
the patch.

> 
> Signed-off-by: Zhe Tao <zhe.tao@intel.com>
> ---
>  doc/guides/nics/i40e.rst               |   7 +++
>  doc/guides/rel_notes/release_16_07.rst |   6 ++
>  drivers/net/i40e/i40e_ethdev.c         | 109 ++++++++++++++++++++++++++-------
>  drivers/net/i40e/i40e_ethdev.h         |   2 +
>  drivers/net/i40e/i40e_pf.c             |  11 +++-
>  5 files changed, 112 insertions(+), 23 deletions(-)
> 
> diff --git a/doc/guides/nics/i40e.rst b/doc/guides/nics/i40e.rst
> index 934eb02..49a0598 100644
> --- a/doc/guides/nics/i40e.rst
> +++ b/doc/guides/nics/i40e.rst
> @@ -366,3 +366,10 @@ Delete all flow director rules on a port:
>  
>     testpmd> flush_flow_director 0
>  
> +Floating VEB
> +~~~~~~~~~~~~~
> +FVL can support floating VEB feature.
> +To enable this feature, the user should pass a devargs parameter to the EAL
> +like "-w 84:00.0,enable_floating=1", and the application will make sure the PMD
> +will use the floating VEB feature for all the VFs created by this PF device.
> +

I think this documentation part really need to be expanded to explain what a
floating VEB is and why you'd use it. If this is well documented elsewhere, e.g.
in the relevant datasheets for NICs using the i40e driver, by all means refer to
that, but keep a summarised account of what it is here in the DPDK docs. Perhaps
you can reuse the description from the release note below, just with an extra
sentence or two about why the PF being down makes a difference, etc.

> diff --git a/doc/guides/rel_notes/release_16_07.rst b/doc/guides/rel_notes/release_16_07.rst
> index 30e78d4..8485b08 100644
> --- a/doc/guides/rel_notes/release_16_07.rst
> +++ b/doc/guides/rel_notes/release_16_07.rst
> @@ -47,6 +47,12 @@ New Features
>    * Dropped specific Xen Dom0 code.
>    * Dropped specific anonymous mempool code in testpmd.
>  
> +* **Added floating VEB support for i40e PF driver.**
> +
> +  Now VFs for i40e can connect to the floating VEB.
> +  With this feature, VFs can communicate with each other, but cannot access
> +  outside network. When PF is down, and VFs can still forward pkts between each
> +  other.

This expanation belongs more in the i40e.rst document above. I think the release
notes only needs a mention that the feature was added and then a link to the
fuller description in the i40e doc.

Regards,
/Bruce