Fix deadlock in subscriber undeclaration (#1649)

* Fix deadlock * Only update matching listener status for last remote subscriber * Remove unnecessary drop after changes * Add unit test for undeclare deadlock
eclipse-zenoh · Dec 10, 2024 · fb2d2bc · fb2d2bc
1 parent b5ca078
commit fb2d2bc
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Showing 2 changed files with 32 additions and 10 deletions.
diff --git a/zenoh/src/api/session.rs b/zenoh/src/api/session.rs
@@ -1574,19 +1574,29 @@ impl SessionInner {
                                     },
                                 }),
                             });
+                            #[cfg(feature = "unstable")]
+                            {
+                                let state = zread!(self.state);
+                                self.update_matching_status(
+                                    &state,
+                                    &sub_state.key_expr,
+                                    MatchingStatusType::Subscribers,
+                                    false,
+                                )
+                            }
                         }
                     } else {
                         drop(state);
-                    }
-                    #[cfg(feature = "unstable")]
-                    {
-                        let state = zread!(self.state);
-                        self.update_matching_status(
-                            &state,
-                            &sub_state.key_expr,
-                            MatchingStatusType::Subscribers,
-                            false,
-                        )
+                        #[cfg(feature = "unstable")]
+                        {
+                            let state = zread!(self.state);
+                            self.update_matching_status(
+                                &state,
+                                &sub_state.key_expr,
+                                MatchingStatusType::Subscribers,
+                                false,
+                            )
+                        }
                     }
                 }
                 SubscriberKind::LivelinessSubscriber => {

diff --git a/zenoh/tests/session.rs b/zenoh/tests/session.rs
@@ -430,3 +430,15 @@ async fn zenoh_session_close_in_background() {
     };
     ztimeout!(close_all);
 }
+
+#[cfg(feature = "unstable")]
+#[tokio::test(flavor = "multi_thread", worker_threads = 4)]
+async fn test_undeclare_subscribers_same_keyexpr() {
+    let key_expr = "test/undeclare/subscribers";
+    let session = zenoh::open(zenoh::Config::default()).await.unwrap();
+    let sub1 = session.declare_subscriber(key_expr).await.unwrap();
+    let sub2 = session.declare_subscriber(key_expr).await.unwrap();
+    tokio::time::sleep(SLEEP).await;
+    ztimeout!(sub1.undeclare()).unwrap();
+    ztimeout!(sub2.undeclare()).unwrap();
+}