svn commit: r189366 - projects/vap7/tools/tools/nanobsd/gateworks

[Sam Leffler]

Attilio Rao wrote:
> 2009/3/4, Sam Leffler <sam at freebsd.org>:
>   
>> Author: sam
>>  Date: Wed Mar  4 16:21:00 2009
>>  New Revision: 189366
>>  URL: http://svn.freebsd.org/changeset/base/189366
>>
>>  Log:
>>   turn off PREEMPTION and mark it broken
>>
>>  Modified:
>>   projects/vap7/tools/tools/nanobsd/gateworks/G2348
>>
>>  Modified: projects/vap7/tools/tools/nanobsd/gateworks/G2348
>>  ==============================================================================
>>  --- projects/vap7/tools/tools/nanobsd/gateworks/G2348   Wed Mar  4 15:45:34 2009        (r189365)
>>  +++ projects/vap7/tools/tools/nanobsd/gateworks/G2348   Wed Mar  4 16:21:00 2009        (r189366)
>>  @@ -39,7 +39,7 @@ options       DDB                     #Enable the kernel debugg
>>   #options               DIAGNOSTIC
>>
>>   options        SCHED_4BSD              #4BSD scheduler
>>  -options                PREEMPTION
>>  +#options               PREEMPTION      # NB: appears broken
>>
>>   options        INET                    #InterNETworking
>>   #options       INET6                   #IPv6 communications protocols
>>
>>     
>
> Could you elaborate a bit on that please?
>   

On my xscale boards I observe network traffic randomly stall under heavy 
interrupt+ctx switch load with PREEMPTION but not w/o (and come back to 
life when I hit a key on the console).  This does not happen under 
HEAD.  I've tried various combinations of SCHED_ULE and SCHED_4BSD, w/ 
KSE and w/o KSE.  I checked code differences but don't see the issue so 
this is a WAR for folks that might use this sample config file to start 
from.  Note I'm certain this is arm/xscale-specific.

If you want more details contact me off-line.  I'd love to squash the 
problem.

    Sam