type runtime.mSpanStateBox

4 uses

	runtime (current package)
		mheap.go#L360: type mSpanStateBox struct {
		mheap.go#L364: func (b *mSpanStateBox) set(s mSpanState) {
		mheap.go#L368: func (b *mSpanStateBox) get() mSpanState {
		mheap.go#L456: 	state       mSpanStateBox // mSpanInUse etc; accessed atomically (get/set methods)