add support for io-uring (#374)

Co-authored-by: Rob Ede <robjtede@icloud.com>

actix-rt/tests/tests.rs

@@ -1,10 +1,6 @@
 use std::{
     future::Future,
-    sync::{
-        atomic::{AtomicBool, Ordering},
-        mpsc::channel,
-        Arc,
-    },
+    sync::mpsc::channel,
     thread,
     time::{Duration, Instant},
 };
@@ -221,8 +217,8 @@ fn system_stop_stops_arbiters() {
     System::current().stop();
     sys.run().unwrap();
 
-    // account for slightly slow thread de-spawns (only observed on windows)
-    thread::sleep(Duration::from_millis(100));
+    // account for slightly slow thread de-spawns
+    thread::sleep(Duration::from_millis(500));
 
     // arbiter should be dead and return false
     assert!(!Arbiter::current().spawn_fn(|| {}));
@@ -231,6 +227,7 @@ fn system_stop_stops_arbiters() {
     arb.join().unwrap();
 }
 
+#[cfg(not(feature = "io-uring"))]
 #[test]
 fn new_system_with_tokio() {
     let (tx, rx) = channel();
@@ -263,8 +260,14 @@ fn new_system_with_tokio() {
     assert_eq!(rx.recv().unwrap(), 42);
 }
 
+#[cfg(not(feature = "io-uring"))]
 #[test]
 fn new_arbiter_with_tokio() {
+    use std::sync::{
+        atomic::{AtomicBool, Ordering},
+        Arc,
+    };
+
     let _ = System::new();
 
     let arb = Arbiter::with_tokio_rt(|| {
@@ -323,3 +326,32 @@ fn spawn_local() {
         h(actix_rt::spawn(async { 1 }));
     })
 }
+
+#[cfg(all(target_os = "linux", feature = "io-uring"))]
+#[test]
+fn tokio_uring_arbiter() {
+    let system = System::new();
+    let (tx, rx) = std::sync::mpsc::channel();
+
+    Arbiter::new().spawn(async move {
+        let handle = actix_rt::spawn(async move {
+            let f = tokio_uring::fs::File::create("test.txt").await.unwrap();
+            let buf = b"Hello World!";
+
+            let (res, _) = f.write_at(&buf[..], 0).await;
+            assert!(res.is_ok());
+
+            f.sync_all().await.unwrap();
+            f.close().await.unwrap();
+
+            std::fs::remove_file("test.txt").unwrap();
+        });
+
+        handle.await.unwrap();
+        tx.send(true).unwrap();
+    });
+
+    assert!(rx.recv().unwrap());
+
+    drop(system);
+}