Re: v2.6.21.4-rt11

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Sat, Jun 09, 2007 at 11:05:07PM +0200, Ingo Molnar wrote:
> 
> i'm pleased to announce the v2.6.21.4-rt11 kernel, which can be 
> downloaded from the usual place:
> 
>      http://people.redhat.com/mingo/realtime-preempt/
>   
> more info about the -rt patchset can be found in the RT wiki:
>    
>      http://rt.wiki.kernel.org
> 
> -rt11 is a bit more experimental than usual: it includes the CFS 
> scheduler. Several people have suggested the inclusion of CFS into the 
> -rt tree: the determinism of the CFS scheduler is a nice match to the 
> determinism offered by PREEMPT_RT. The port of CFS to -rt was done by 
> Dinakar Guniguntala. Tested on i686 and x86_64.
> 
> to build a 2.6.21.4-rt11 tree, the following patches should be applied:
>   
>     http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.21.4.tar.bz2
>     http://people.redhat.com/mingo/realtime-preempt/patch-2.6.21.4-rt11

2.6.21.4-rt12 boots on 4-CPU Opteron and passes several hours of
rcutorture.  However, if I simply do "modprobe rcutorture", the kernel
threads do not spread across the CPUs as I would expect them to, even
given CFS.  Instead, the readers all stack up on a single CPU, and I
have to use the "taskset" command to spread them out manually.  Is there
some config parameter I am missing out on?

						Thanx, Paul