Function wait_event_until 

pub fn wait_event_until(
    vm: &mut Vm,
    deadline: Option<Instant>,
    arm: impl FnOnce(Wake) -> bool,
) -> Option<bool>

As wait_event, with a deadline: returns Some(timed_out) when it waited cooperatively (timed_out is true if the deadline passed before a wakeup), None when the caller must block the thread itself. After Some(false), re-check the condition.