[ovs-dev] Incorporating OF1.4 eviction

[Ben Pfaff]

On Tue, Apr 22, 2014 at 10:03:00PM +0530, Shivanker Goel wrote:
>   But what I've been trying to do for a while now, is interacting with the
> controller with respect to this. The controller should be able to enable
> eviction in a table using an OFP_TABLE_MOD packet, it should be able to
> modify the importance of a flow using the OFPT_FLOW_MOD packet, it should
> be able to get the importance parameters in the statistics alongwith the
> OFP_FLOW_REMOVED and OFPMP_FLOW packets. It would be of great help to me if
> someone could point me to some piece of code which does all this handling
> for OVS. I've been trying but haven't been successful in doing this so far.

The code you want to look at is mostly in lib/ofp-util.[ch] and
ofproto/ofproto.c.  The former is an abstraction layer over OpenFlow
message encoding and decoding.  You will want to modify it to encode and
decode the 'importance' field.  The latter actually handles all the
OpenFlow messages flowing through a switch.  You will need to modify it
to actually use the importance field.