[ovs-dev] [PATCH v1 2/2] ofproto: Implement OF1.4 Group & Meter change notification messages

[Ben Pfaff]

On Thu, Jul 23, 2015 at 05:06:36PM +0530, niti1489 at gmail.com wrote:
> From: Niti Rohilla <niti.rohilla at tcs.com>
> 
> This patch adds support for Openflow1.4 Group & meter change notification
> messages. In a multi controller environment, when a controller modifies the
> state of group and meter table, the request that successfully modifies this
> state is forwarded to other controllers. Other controllers are informed with
> the OFPT_REQUESTFORWARD message. Request forwarding is enabled on a per
> controller channel basis using the Set Asynchronous Configuration Message.
> 
> Signed-off-by: Niti Rohilla <niti.rohilla at tcs.com>

Thank you for working on this.  I have some comments.

ofp_print_requestforward() will abort the program if a received
OFPT_REQUESTFORWARD message contains any message other than a group mod
or a meter mod.  That's not acceptable.

In ofputil_encode_requestforward(), for efficiency, the final argument
to ofpraw_alloc_xid() should be the length of 'rf'.

The message inside OFPT_REQUESTFORWARD needs to have the same OpenFlow
version as the wrapper.  ofputil_decode_requestforward() should check
that, and report an error if it differs.  It also means
ofputil_encode_requestforward() doesn't need a protocol version
parameter (since it can be inferred from 'rf') and that
connmgr_send_requestforward() needs to somehow make the inner message
compatible with 'ofconn'.  I think that probably has to be done by
re-encoding the inner message for the protocol in use on each 'ofconn'.