var runtime.extraMWaiters

4 uses

	runtime (current package)
		cgocall.go#L397: 	if gp.m.needextram || extraMWaiters.Load() > 0 {
		proc.go#L2493: 	c := extraMWaiters.Swap(0)
		proc.go#L2730: 	extraMWaiters atomic.Uint32
		proc.go#L2758: 				extraMWaiters.Add(1)