private void advanceRunState(int targetState){
  for (; ; ) {
    int c=ctl.get();
    if (runStateAtLeast(c,targetState) || ctl.compareAndSet(c,ctlOf(targetState,workerCountOf(c))))     break;
  }
}

private void advanceRunState ( int targetState ) { for ( ; ; ) { int c = ctl . get ( ) ; if ( runStateAtLeast ( c , targetState ) || ctl . compareAndSet ( c , ctlOf ( targetState , workerCountOf ( c ) ) ) ) break ; } }
transitions runstate to given target , or leaves it alone if already at least the given target .
