The matrix:
IW = am I in initializaton wait
RU = am I runnable
Resched = do we need to reschedule
Reset = set IW to this
x = don't care
IW RU Resched Reset
T T T F
T F F T
F T F F
F F x x
So resched = IR & RU
IW = !RU
We return resched so caller knows to tickle the scheduler