[ovs-discuss] Datapath loop

Ben Pfaff blp at nicira.com
Wed Oct 20 16:17:22 UTC 2010


On Wed, Oct 20, 2010 at 12:21:07PM -0200, Henrique Rodrigues wrote:
> I've been studying the Open vSwitch code and I couldn't understand what the
> "datapath loop" means...
> I noticed the comment before the struct loop_counter declaration ("*We limit
> the number of times that we pass into dp_process_received_packet() to avoid
> blowing out the stack in the event that we have a loop"*) but I couldn't
> figure out what the "datapath loop" means.
> 
> When this "datapath loop" happens? In which situation the
> dp_process_received_packet() is called within a "loop"?

One way for a loop to happen would be for a flow to send a packet across
a patch port to another datapath, which in turn contains a flow that
send the packet across a different patch port to the originating
datapath, and so on.




More information about the discuss mailing list