Subject: Re: [patch net-next 01/13] openvswitch: split flow structures into ovs specific and generic ones

From: Jamal Hadi Salim <[email-masked]>
Date: Wed, 03 Sep 2014 17:22:28 -0400

On 09/03/14 14:41, Pravin Shelar wrote:
> On Wed, Sep 3, 2014 at 2:24 AM, Jiri Pirko <[email-masked]> wrote:

> HW offload API should be separate from OVS module.

The above part i agree with. Infact it is very odd that it seems
hard to get this point across ;->

> This has following
> advantages.
> 1. It can be managed by OVS userspace vswitchd process which has much
> better context to setup hardware flow table. Once we add capabilities
> for swdev, it is much more easier for vswitchd process to choose
> correct (hw or sw) flow table for given flow.

This i disagree with.
The desire is to have existing user tools to work with offloads.
When necessary, we then create new tools.
Existing tools may need to be taught to do selectively do
hardware vs software offload. We have a precedence with
bridging code which selectively offloads to hardware using iproute2.

> 2. Other application that wants to use HW offload does not have
> dependency on OVS kernel module.

Or on OF for that matter.

> 3. Hardware and software datapath remains separate, these two
> components has no dependency on each other, both can be developed
> independent of each other.
>

The basic definition of "offload" implies dependency;-> So,
I strongly disagree. You may need to go backwards and look at
views expressed on this (other than emails - theres slideware).

cheers,
jamal