> One thing which occurred to me too:
> 
> we need to optimize both the case when there _is_ a zombie or
> stopped child (i.e. do fast lookup) and the case where isn't
> (avoid scanning the list if there is no waiting child).

My current plan is to count the number of children in SSTOP/SZOMB
and to requeue them to the top of the p_children list.
find_stopped_child() can then be optimised the case when there are 
no such children.

It requires less re-queueing than using a separate list - you don't
need to move them on the SSTOP->SACTIVE transition, nor if they are
already at the queue head.

I've got bogged down (I easily get sidetracked) with the brokenness
of the MP locking....

	David

-- 
David Laight: david@l8s.co.uk