Function stop

src/bthread/parking_lot.h:82–85

Wakeup suspended wait() and make them unwaitable ever.

    // Wakeup suspended wait() and make them unwaitable ever. 
    void stop() {
        _pending_signal.fetch_or(1);
        futex_wake_private(&_pending_signal, 10000);
    }

private:
    // higher 31 bits for signalling, LSB for stopping.