s atomic.Uint8
}

// It is nosplit to match get, below.

//go:nosplit
func (b *mSpanStateBox) set(s mSpanState) {
	b.s.Store(uint8(s))
}

// It is nosplit because it's called indirectly by typedmemclr,
// which must not be preempted.

//go:nosplit
func (b *mSpanStateBox) get() mSpanState {
	return mSpanState(b.s.Load())
}

// mSpanList heads a linked list of spans.
type mSpanList struct {