util: enable loom tests (#7644)

Co-authored-by: Benjamin Ran <[email protected]>

tokio-util/src/sync/mod.rs

@@ -15,3 +15,6 @@ pub use poll_semaphore::PollSemaphore;
 
 mod reusable_box;
 pub use reusable_box::ReusableBoxFuture;
+
+#[cfg(test)]
+mod tests;

tokio-util/src/sync/tests/loom_cancellation_token.rs

@@ -100,6 +100,9 @@ fn drop_token_no_child() {
     });
 }
 
+// Temporarily disabled due to a false positive in loom -
+// see https://github.com/tokio-rs/tokio/pull/7644#issuecomment-3328381344
+#[ignore]
 #[test]
 fn drop_token_with_children() {
     loom::model(|| {
@@ -125,6 +128,9 @@ fn drop_token_with_children() {
     });
 }
 
+// Temporarily disabled due to a false positive in loom -
+// see https://github.com/tokio-rs/tokio/pull/7644#issuecomment-3328381344
+#[ignore]
 #[test]
 fn drop_and_cancel_token() {
     loom::model(|| {
@@ -150,6 +156,9 @@ fn drop_and_cancel_token() {
     });
 }
 
+// Temporarily disabled due to a false positive in loom -
+// see https://github.com/tokio-rs/tokio/pull/7644#issuecomment-3328381344
+#[ignore]
 #[test]
 fn cancel_parent_and_child() {
     loom::model(|| {

tokio-util/src/sync/tests/mod.rs

@@ -1 +1,2 @@
-
+#[cfg(loom)]
+mod loom_cancellation_token;