refactor: use raft_loop_cond instead of raft.loop-needed event

src/traft/node.rs

@@ -11,7 +11,7 @@ use ::raft::StateRole as RaftStateRole;
 use ::raft::INVALID_ID;
 use ::tarantool::error::TransactionError;
 use ::tarantool::fiber;
-use ::tarantool::fiber::Mutex;
+use ::tarantool::fiber::{Cond, Mutex};
 use ::tarantool::proc;
 use ::tarantool::tlua;
 use ::tarantool::transaction::start_transaction;
@@ -73,6 +73,7 @@ pub struct Node {
     _main_loop: fiber::UnitJoinHandle<'static>,
     _conf_change_loop: fiber::UnitJoinHandle<'static>,
     status: Rc<RefCell<Status>>,
+    raft_loop_cond: Rc<Cond>,
     notifications: Rc<RefCell<HashMap<LogicalClock, Notify>>>,
     topology_cache: CachedCell<RaftTerm, Topology>,
     lc: Cell<Option<LogicalClock>>,
@@ -100,14 +101,15 @@ impl Node {
             raft_state: "Follower".into(),
             is_ready: false,
         }));
-
+        let raft_loop_cond = Rc::new(Cond::new());
         let notifications = Rc::new(RefCell::new(HashMap::new()));
 
         let main_loop_fn = {
             let status = status.clone();
             let raw_node = raw_node.clone();
+            let raft_loop_cond = raft_loop_cond.clone();
             let notifications = notifications.clone();
-            move || raft_main_loop(status, raw_node, notifications)
+            move || raft_main_loop(status, raw_node, raft_loop_cond, notifications)
         };
 
         let conf_change_loop_fn = {
@@ -120,6 +122,7 @@ impl Node {
             raft_id: cfg.id,
             notifications,
             status,
+            raft_loop_cond,
             _main_loop: fiber::Builder::new()
                 .name("raft_main_loop")
                 .proc(main_loop_fn)
@@ -395,7 +398,7 @@ impl Node {
         let mut raw_node = self.raw_node.lock();
         let res = f(&mut *raw_node);
         drop(raw_node);
-        event::broadcast(Event::RaftLoopNeeded);
+        self.raft_loop_cond.broadcast();
         res
     }
 
@@ -605,6 +608,7 @@ fn handle_messages(messages: Vec<raft::Message>, pool: &ConnectionPool) {
 fn raft_main_loop(
     status: Rc<RefCell<Status>>,
     raw_node: Rc<Mutex<RawNode>>,
+    raft_loop_cond: Rc<Cond>,
     notifications: Rc<RefCell<HashMap<LogicalClock, Notify>>>,
 ) {
     let mut next_tick = Instant::now() + Node::TICK;
@@ -625,7 +629,7 @@ fn raft_main_loop(
             .borrow_mut()
             .retain(|_, notify: &mut Notify| !notify.is_closed());
 
-        event::wait_timeout(Event::RaftLoopNeeded, Node::TICK).expect("Events must be initialized");
+        raft_loop_cond.wait_timeout(Node::TICK);
 
         let mut raw_node = raw_node.lock();
         let now = Instant::now();