From 0793781824dead5f78959eaa3e945bc64eeea632 Mon Sep 17 00:00:00 2001
From: Romain Ruetschi <romain@informal.systems>
Date: Tue, 4 Jun 2024 16:15:18 +0200
Subject: [PATCH] feat(code): Increase timeouts by the configured delta when
 they elapse

---
 code/actors/src/consensus.rs |   5 +-
 code/actors/src/timers.rs    | 103 +++++++++++++++++++++++++++--------
 2 files changed, 83 insertions(+), 25 deletions(-)

diff --git a/code/actors/src/consensus.rs b/code/actors/src/consensus.rs
index c32c0d0e8..254725287 100644
--- a/code/actors/src/consensus.rs
+++ b/code/actors/src/consensus.rs
@@ -309,7 +309,7 @@ where
     ) -> Result<(), ractor::ActorProcessingErr> {
         match &input {
             DriverInput::NewRound(_, _, _) => {
-                state.timers.cast(TimersMsg::Reset)?;
+                state.timers.cast(TimersMsg::CancelAllTimeouts)?;
             }
 
             DriverInput::ProposeValue(round, _) => state
@@ -646,7 +646,8 @@ where
             }
 
             Msg::MoveToHeight(height) => {
-                state.timers.cast(TimersMsg::Reset)?;
+                state.timers.cast(TimersMsg::CancelAllTimeouts)?;
+                state.timers.cast(TimersMsg::ResetTimeouts)?;
 
                 let validator_set = self.get_validator_set(height).await?;
                 state.driver.move_to_height(height, validator_set);
diff --git a/code/actors/src/timers.rs b/code/actors/src/timers.rs
index 3cdcb484a..1f4ad607b 100644
--- a/code/actors/src/timers.rs
+++ b/code/actors/src/timers.rs
@@ -19,8 +19,8 @@ impl TimeoutElapsed {
 }
 
 pub struct Timers<M> {
-    config: Config,
     listener: ActorRef<M>,
+    initial_config: Config,
 }
 
 impl<M> Timers<M>
@@ -28,34 +28,50 @@ where
     M: From<TimeoutElapsed> + ractor::Message,
 {
     pub async fn spawn(
-        config: Config,
+        initial_config: Config,
         listener: ActorRef<M>,
     ) -> Result<(ActorRef<Msg>, JoinHandle<()>), ractor::SpawnErr> {
-        Actor::spawn(None, Self { config, listener }, ()).await
+        Actor::spawn(
+            None,
+            Self {
+                listener,
+                initial_config,
+            },
+            initial_config,
+        )
+        .await
     }
 
     pub async fn spawn_linked(
-        config: Config,
+        initial_config: Config,
         listener: ActorRef<M>,
         supervisor: ActorCell,
     ) -> Result<(ActorRef<Msg>, JoinHandle<()>), ractor::SpawnErr> {
-        Actor::spawn_linked(None, Self { config, listener }, (), supervisor).await
-    }
-
-    pub fn timeout_duration(&self, step: &TimeoutStep) -> Duration {
-        match step {
-            TimeoutStep::Propose => self.config.timeout_propose,
-            TimeoutStep::Prevote => self.config.timeout_prevote,
-            TimeoutStep::Precommit => self.config.timeout_precommit,
-            TimeoutStep::Commit => self.config.timeout_commit,
-        }
+        Actor::spawn_linked(
+            None,
+            Self {
+                listener,
+                initial_config,
+            },
+            initial_config,
+            supervisor,
+        )
+        .await
     }
 }
 
 pub enum Msg {
+    /// Schedule the given timeout
     ScheduleTimeout(Timeout),
+
+    /// Cancel the given timeout
     CancelTimeout(Timeout),
-    Reset,
+
+    /// Cancel all the timeouts
+    CancelAllTimeouts,
+
+    /// Reset all timeouts values to their original values
+    ResetTimeouts,
 
     // Internal messages
     #[doc(hidden)]
@@ -66,9 +82,41 @@ type TimerTask = JoinHandle<Result<(), MessagingErr<Msg>>>;
 
 #[derive(Default)]
 pub struct State {
+    config: Config,
     timers: HashMap<Timeout, TimerTask>,
 }
 
+impl State {
+    pub fn timeout_elapsed(&mut self, timeout: &Timeout) {
+        self.timers.remove(timeout);
+        self.increase_timeout(&timeout.step);
+    }
+
+    pub fn increase_timeout(&mut self, step: &TimeoutStep) {
+        match step {
+            TimeoutStep::Propose => {
+                self.config.timeout_propose += self.config.timeout_propose_delta
+            }
+            TimeoutStep::Prevote => {
+                self.config.timeout_prevote += self.config.timeout_prevote_delta
+            }
+            TimeoutStep::Precommit => {
+                self.config.timeout_precommit += self.config.timeout_precommit_delta
+            }
+            TimeoutStep::Commit => (),
+        }
+    }
+
+    pub fn timeout_duration(&self, step: &TimeoutStep) -> Duration {
+        match step {
+            TimeoutStep::Propose => self.config.timeout_propose,
+            TimeoutStep::Prevote => self.config.timeout_prevote,
+            TimeoutStep::Precommit => self.config.timeout_precommit,
+            TimeoutStep::Commit => self.config.timeout_commit,
+        }
+    }
+}
+
 #[async_trait]
 impl<M> Actor for Timers<M>
 where
@@ -76,14 +124,17 @@ where
 {
     type Msg = Msg;
     type State = State;
-    type Arguments = ();
+    type Arguments = Config;
 
     async fn pre_start(
         &self,
         _myself: ActorRef<Msg>,
-        _args: (),
+        config: Config,
     ) -> Result<State, ActorProcessingErr> {
-        Ok(State::default())
+        Ok(State {
+            config,
+            ..Default::default()
+        })
     }
 
     async fn handle(
@@ -94,7 +145,7 @@ where
     ) -> Result<(), ActorProcessingErr> {
         match msg {
             Msg::ScheduleTimeout(timeout) => {
-                let duration = self.timeout_duration(&timeout.step);
+                let duration = state.timeout_duration(&timeout.step);
                 let task = send_after(duration, myself.get_cell(), move || {
                     Msg::TimeoutElapsed(timeout)
                 });
@@ -108,15 +159,21 @@ where
                 }
             }
 
-            Msg::Reset => {
+            Msg::TimeoutElapsed(timeout) => {
+                state.timeout_elapsed(&timeout);
+                self.listener.cast(TimeoutElapsed(timeout).into())?;
+            }
+
+            Msg::CancelAllTimeouts => {
+                // Cancel all the timers
                 for (_, task) in state.timers.drain() {
                     task.abort();
                 }
             }
 
-            Msg::TimeoutElapsed(timeout) => {
-                state.timers.remove(&timeout);
-                self.listener.cast(TimeoutElapsed(timeout).into())?;
+            Msg::ResetTimeouts => {
+                // Reset the timeouts to their original values
+                state.config = self.initial_config;
             }
         }