Struct wait_queue::WaitQueue

pub struct WaitQueue<P = Spin>where
    P: DeadlockPrevention,{ /* private fields */ }

A queue of tasks waiting for an event to occur.

When tasks are popped off the front of the queue via notify_one() or notify_all(), they are each unblocked.

The wait queue uses a mutex internally and hence exposes a deadlock prevention type parameter P, which is [Spin] by default. This parameter should only be set to another deadlock prevention method if a spin-based mutex could lead to deadlock, e.g., in an interrupt context. You do not need to use the DisablePreemption deadlock prevention method here to avoid scheduler race conditions – that is already accounted for in this wait queue’s implementation, even when using the [Spin] default.

Implementations

impl<P> WaitQueue<P>where P: DeadlockPrevention,

pub const fn new() -> Self

Creates a new empty wait queue.

pub fn wait_until<F, T>(&self, condition: F) -> Twhere F: FnMut() -> Option<T>,

Blocks the current task until the given condition succeeds.

pub fn notify_one(&self) -> bool

Notifies the first task in the wait queue.

If it fails to unblock the first task, it will continue unblocking subsequent tasks until a task is successfully unblocked.

pub fn notify_all(&self)

Notifies all the tasks in the wait queue.