question: private int timedAwaitWork ( WorkQueue w , long c ) { int stat = 0 ; int scale = 1 - ( short ) ( c > > > TC_SHIFT ) ; long deadline = ( ( ( scale <= 0 ) ? 1 : scale ) * IDLE_TIMEOUT_MS + System . currentTimeMillis ( ) ) ; if ( ( runState >= 0 || ( stat = tryTerminate ( false , false ) ) > 0 ) && w != null && w . scanState < 0 ) { int ss ; AuxState aux ; w . parker = Thread . currentThread ( ) ; if ( w . scanState < 0 ) LockSupport . parkUntil ( this , deadline ) ; w . parker = null ; if ( ( runState & STOP ) != 0 ) stat = w . qlock = - 1 ; else if ( ( ss = w . scanState ) < 0 && ! Thread . interrupted ( ) && ( int ) c == ss && ( aux = auxState ) != null && ctl == c && deadline - System . currentTimeMillis ( ) <= TIMEOUT_SLOP_MS ) { aux . lock ( ) ; try { WorkQueue [ ] ws ; int cfg = w . config , idx = cfg & SMASK ; long nc = ( ( UC_MASK & ( c - TC_UNIT ) ) | ( SP_MASK & w . stackPred ) ) ; if ( ( runState & STOP ) == 0 && ( ws = workQueues ) != null && idx < ws . length && idx >= 0 && ws [ idx ] == w && U . compareAndSwapLong ( this , CTL , c , nc ) ) { ws [ idx ] = null ; w . config = cfg | UNREGISTERED ; stat = w . qlock = - 1 ; } } finally { aux . unlock ( ) ; } } } return stat ; }
target:  Possibly triggers shutdown and tries (once) to block worker when pool is (or may be) quiescent. Waits up to a duration determined by number of workers.  On timeout, if ctl has not changed, terminates the worker, which will in turn wake up another worker to possibly repeat this process.