Re: http://www.holm.cc/stress/log/cons141.html

On Thu, Jul 14, 2005 at 03:10:43PM +0400, Gleb Smirnoff wrote:
>   Colleagues,
> 
> On Wed, Jul 13, 2005 at 10:51:55AM +0200, Peter Holm wrote:
> P> > how often the panic in subject fires? I guess it is related to the problem
> P> > discussed in this thread [1], and may be even the patch I've posted there
> P> > will help.
> P> >
> P> 
> P> The panic is almost instantanious if I run the stress test while doing
> P> an "arp -d xxx".
> 
> The attached WIP patch helps me. The [1] script can't drop my box to panic
> anymore, when running in 15 instances on 4-x CPU box.
> 

Yes, works for me! I've been testing for three hours without any
problems and then ran into another unrelated livelock.

Great work!

- Peter

> The idea of the patch is to hold rtentry lock during all the manipulation
> of the rtentry itself and its llinfo. To achieve this, I've changed 
> rt_check() and arplookup() to return a locked rtentry.
> 
> Not everything is OK, yet. For example when I turn witness off via sysctl,
> and all the scripts are running at this moment, I get a panic in
> route_output() - "sleeping thread owns not-sleepable lock".
> 
> [1] ( while (true); do
> 	arp -d 81.19.64.111  >/dev/null 2>&1;
> 	ping -c 1 -t 1 81.19.64.111 >/dev/null 2>&1;
>       done) &
> 
> -- 
> Totus tuus, Glebius.
> GLEBIUS-RIPN GLEB-RIPE

-- 
Peter Holm