Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 55 insertions, 0 deletions

diff --git a/third_party/rust/tokio/src/time/driver/tests/mod.rs b/third_party/rust/tokio/src/time/driver/tests/mod.rs
new file mode 100644
index 0000000000..88ff5525da
--- /dev/null
+++ b/third_party/rust/tokio/src/time/driver/tests/mod.rs
@@ -0,0 +1,55 @@
+use crate::park::Unpark;
+use crate::time::driver::Inner;
+use crate::time::Instant;
+
+use loom::thread;
+
+use std::sync::atomic::Ordering;
+use std::sync::Arc;
+
+struct MockUnpark;
+
+impl Unpark for MockUnpark {
+    fn unpark(&self) {}
+}
+
+#[test]
+fn balanced_incr_and_decr() {
+    const OPS: usize = 5;
+
+    fn incr(inner: Arc<Inner>) {
+        for _ in 0..OPS {
+            inner.increment().expect("increment should not have failed");
+            thread::yield_now();
+        }
+    }
+
+    fn decr(inner: Arc<Inner>) {
+        let mut ops_performed = 0;
+        while ops_performed < OPS {
+            if inner.num(Ordering::Relaxed) > 0 {
+                ops_performed += 1;
+                inner.decrement();
+            }
+            thread::yield_now();
+        }
+    }
+
+    loom::model(|| {
+        let unpark = Box::new(MockUnpark);
+        let instant = Instant::now();
+
+        let inner = Arc::new(Inner::new(instant, unpark));
+
+        let incr_inner = inner.clone();
+        let decr_inner = inner.clone();
+
+        let incr_hndle = thread::spawn(move || incr(incr_inner));
+        let decr_hndle = thread::spawn(move || decr(decr_inner));
+
+        incr_hndle.join().expect("should never fail");
+        decr_hndle.join().expect("should never fail");
+
+        assert_eq!(inner.num(Ordering::SeqCst), 0);
+    })
+}