why the Lock and Unlock method need "m.nodem.Lock"?

[zjfqxa]

Hi hjr265,

as I have known, the redis set operation with "NX" will promise distributed lock,
reply, err := redis.String(conn.Do("SET", m.name, value, "NX", "PX", int(m.expiry/time.Millisecond)))

so it confused me, why the Lock and Unlock method need m.nodem.Lock? and will the m.nodem.Lock lead to deadlock?

func (m *Mutex) Lock() error {
	m.nodem.Lock()
	defer m.nodem.Unlock()
        ...
}