Use std::sync::OnceLock instead of async_lock::OnceCell

Author: taiki-e

Cargo.toml

@@ -26,7 +26,6 @@ name = "timer"
 harness = false
 
 [dependencies]
-async-lock = "3.0.0"
 cfg-if = "1"
 concurrent-queue = "2.2.0"
 futures-io = { version = "0.3.28", default-features = false, features = ["std"] }

src/driver.rs

@@ -1,13 +1,12 @@
 use std::cell::{Cell, RefCell};
 use std::future::Future;
 use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
-use std::sync::Arc;
+use std::sync::{Arc, OnceLock};
 use std::task::Waker;
 use std::task::{Context, Poll};
 use std::thread;
 use std::time::{Duration, Instant};
 
-use async_lock::OnceCell;
 use futures_lite::pin;
 use parking::Parker;
 
@@ -18,9 +17,9 @@ static BLOCK_ON_COUNT: AtomicUsize = AtomicUsize::new(0);
 
 /// Unparker for the "async-io" thread.
 fn unparker() -> &'static parking::Unparker {
-    static UNPARKER: OnceCell<parking::Unparker> = OnceCell::new();
+    static UNPARKER: OnceLock<parking::Unparker> = OnceLock::new();
 
-    UNPARKER.get_or_init_blocking(|| {
+    UNPARKER.get_or_init(|| {
         let (parker, unparker) = parking::pair();
 
         // Spawn a helper thread driving the reactor.

src/reactor.rs

@@ -8,11 +8,10 @@ use std::mem;
 use std::panic;
 use std::pin::Pin;
 use std::sync::atomic::{AtomicUsize, Ordering};
-use std::sync::{Arc, Mutex, MutexGuard};
+use std::sync::{Arc, Mutex, MutexGuard, OnceLock};
 use std::task::{Context, Poll, Waker};
 use std::time::{Duration, Instant};
 
-use async_lock::OnceCell;
 use concurrent_queue::ConcurrentQueue;
 use futures_lite::ready;
 use polling::{Event, Events, Poller};
@@ -93,9 +92,9 @@ pub(crate) struct Reactor {
 impl Reactor {
     /// Returns a reference to the reactor.
     pub(crate) fn get() -> &'static Reactor {
-        static REACTOR: OnceCell<Reactor> = OnceCell::new();
+        static REACTOR: OnceLock<Reactor> = OnceLock::new();
 
-        REACTOR.get_or_init_blocking(|| {
+        REACTOR.get_or_init(|| {
             crate::driver::init();
             Reactor {
                 poller: Poller::new().expect("cannot initialize I/O event notification"),