Re: [PATCH net-next 4/7] devlink: Add E-Switch inline mode control

Sun, Jan 08, 2017 at 11:49:20AM CET, ogerlitz@mellanox.com wrote:

On 1/8/2017 12:29 PM, Jiri Pirko wrote:

quoted

Mon, Nov 21, 2016 at 02:05:58PM CET, saeedm@mellanox.com wrote:

quoted

From: Roi Dayan <redacted>

Some HWs need the VF driver to put part of the packet headers on the
TX descriptor so the e-switch can do proper matching and steering.

Could you please elaborate a bit about possible use-cases for different
modes? Thanks.

As written in the change log, some HW models have this requirement that the
header set you want eswitch matching on (e.g L2/L3) is present as MD on the
xmit DMA descriptor.

To address these requirements, following the admin devlink directive the FW
advertizes that
to the VF, they are doing so in their xmit logic and the host driver enforces
that the VF has the proper inline mode before we are willing to offload
eswitch matching rules. If the VF doesn't obey to the requirement the packets
are dropped by HW.

Okay, makes sense. Do you expect this will ever have to be needed
per-vf? In general, not only for mlx* drivers. I believe that this is
an e-switch requirement so it should be same for all connected VFs,
right?

Thanks!