[Xorp-hackers] XRL is busy and does not send

[Ben Greear]

On 05/19/2011 08:24 AM, Philip Hugg wrote:
> Hello everyone,
>
> I'm currently working on Xorp-OLSR.
>
> The problem with OLSR is the route flapping.
> I've managed to find a few obvious bugs up to now however this one
> involves the interface to the XRL. I'm not sure how to fix.
>
> The problem I found is in file 'xrl_port.cc' where OLSR is sending the
> packets

>
> Now what I'm seeing is the debug message "PortOutput ...: send skipped
> (pending XRL)".
> It doesn't happen all the time but it's just enough to cause route flapping.
>
> My question is how could I fix the pending issue without causing a race
> condition in the code?

I took a look at that code, and it looks quite fragile.
As the code exists currently, I suppose you'd
need to check the results of send_to and queue up pkts for retransmit
if sending failed.

Maybe it was to make sure some initial config logic completed before
send_to started functioning?

Maybe use a different flag like _setup_complete that is set in
socket_setup_complete() and have send_to fail to send until
setup is complete?

It doesn't look like an general XRL problem to me, by the way.

Thanks,
Ben

-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com