ULE/yielding patch for testing.

[NIIMI Satoshi]

Hi,

Jeff Roberson wrote:
> 2)  Restores old sched_yield() behavior from 6.x.  This was changed in 
> -current unintentionally I think.

sched_yield() is now very fast with SCHED_ULE.  On my test, it's faster
than 6.2-REL even with HZ=100.

> Those of you still using 4BSD can also verify that the yield changes 
> don't cause any problems there.

Unfortunately, sched_yield() is still very slow with SCHED_4BSD.

Thanks,
-- 
NIIMI Satoshi