From a67a88c8ef756900222c31056363a535d37025e4 Mon Sep 17 00:00:00 2001
From: Tyera Eulberg <tyera@solana.com>
Date: Wed, 27 Feb 2019 11:58:01 -0700
Subject: [PATCH] Hoist EntrySender in ReplayStage

---
 src/replay_stage.rs | 75 ++++++++++++++++++++++++++++-----------------
 1 file changed, 47 insertions(+), 28 deletions(-)

diff --git a/src/replay_stage.rs b/src/replay_stage.rs
index 45e4e2cf4f..1eaa59d31e 100644
--- a/src/replay_stage.rs
+++ b/src/replay_stage.rs
@@ -60,12 +60,9 @@ impl ReplayStage {
         bank: &Arc<Bank>,
         cluster_info: &Arc<RwLock<ClusterInfo>>,
         voting_keypair: &Option<Arc<T>>,
-        ledger_entry_sender: &EntrySender,
         current_blob_index: &mut u64,
         last_entry_id: &mut Hash,
         subscriptions: &Arc<RpcSubscriptions>,
-        slot: u64,
-        parent_slot: Option<u64>,
     ) -> Result<()> {
         // Coalesce all the available entries into a single vote
         submit(
@@ -89,16 +86,13 @@ impl ReplayStage {
 
         let num_ticks = bank.tick_height();
         let slot_height = bank.slot_height();
-        let leader_id = leader_schedule_utils::slot_leader(bank);
+
         let mut num_ticks_to_next_vote =
             leader_schedule_utils::num_ticks_left_in_slot(bank, num_ticks);
 
-        let mut entry_tick_height = num_ticks;
-        let mut entries_with_meta = Vec::new();
         for (i, entry) in entries.iter().enumerate() {
             inc_new_counter_info!("replicate-stage_bank-tick", bank.tick_height() as usize);
             if entry.is_tick() {
-                entry_tick_height += 1;
                 if num_ticks_to_next_vote == 0 {
                     num_ticks_to_next_vote = bank.ticks_per_slot();
                 }
@@ -108,14 +102,6 @@ impl ReplayStage {
                 "replicate-stage_tick-to-vote",
                 num_ticks_to_next_vote as usize
             );
-            entries_with_meta.push(EntryMeta {
-                tick_height: entry_tick_height,
-                slot,
-                slot_leader: leader_id,
-                num_ticks_left_in_slot: num_ticks_to_next_vote,
-                parent_slot,
-                entry: entry.clone(),
-            });
             // If it's the last entry in the vector, i will be vec len - 1.
             // If we don't process the entry now, the for loop will exit and the entry
             // will be dropped.
@@ -149,7 +135,6 @@ impl ReplayStage {
 
         // If leader rotation happened, only write the entries up to leader rotation.
         entries.truncate(num_entries_to_write);
-        entries_with_meta.truncate(num_entries_to_write);
         *last_entry_id = entries
             .last()
             .expect("Entries cannot be empty at this point")
@@ -161,12 +146,6 @@ impl ReplayStage {
         );
 
         let entries_len = entries.len() as u64;
-        // TODO: In line with previous behavior, this will write all the entries even if
-        // an error occurred processing one of the entries (causing the rest of the entries to
-        // not be processed).
-        if entries_len != 0 {
-            ledger_entry_sender.send(entries_with_meta)?;
-        }
 
         *current_blob_index += entries_len;
         res?;
@@ -193,7 +172,7 @@ impl ReplayStage {
     where
         T: 'static + KeypairUtil + Send + Sync,
     {
-        let (ledger_entry_sender, ledger_entry_receiver) = channel();
+        let (forward_entry_sender, forward_entry_receiver) = channel();
         let exit_ = exit.clone();
         let to_leader_sender = to_leader_sender.clone();
         let subscriptions_ = subscriptions.clone();
@@ -319,20 +298,26 @@ impl ReplayStage {
                             vec![]
                         }
                     };
-                    let parent_slot = blocktree.meta(slot).unwrap().map(|meta| meta.parent_slot);
 
                     if !entries.is_empty() {
+                        if let Err(e) = Self::forward_entries(
+                            &entries,
+                            slot,
+                            current_leader_id,
+                            &bank,
+                            &blocktree,
+                            &forward_entry_sender,
+                        ) {
+                            error!("{} forward_entries failed: {:?}", my_id, e);
+                        }
                         if let Err(e) = Self::process_entries(
                             entries,
                             &bank,
                             &cluster_info,
                             &voting_keypair,
-                            &ledger_entry_sender,
                             &mut current_blob_index,
                             &mut last_entry_id,
                             &subscriptions_,
-                            slot,
-                            parent_slot,
                         ) {
                             error!("{} process_entries failed: {:?}", my_id, e);
                         }
@@ -410,7 +395,7 @@ impl ReplayStage {
             })
             .unwrap();
 
-        (Self { t_replay, exit }, ledger_entry_receiver)
+        (Self { t_replay, exit }, forward_entry_receiver)
     }
 
     pub fn close(self) -> thread::Result<()> {
@@ -450,6 +435,40 @@ impl ReplayStage {
         let next_slots = blocktree.get_slots_since(&[slot_index]).expect("Db error");
         next_slots.first().cloned()
     }
+
+    fn forward_entries(
+        entries: &[Entry],
+        slot: u64,
+        slot_leader: Pubkey,
+        bank: &Arc<Bank>,
+        blocktree: &Arc<Blocktree>,
+        forward_entry_sender: &EntrySender,
+    ) -> Result<()> {
+        let parent_slot = blocktree.meta(slot).unwrap().map(|meta| meta.parent_slot);
+        let mut entry_tick_height = bank.tick_height();
+        let mut num_ticks_left_in_slot =
+            bank.ticks_per_slot() - entry_tick_height % bank.ticks_per_slot() - 1;
+        let mut entries_with_meta = Vec::new();
+        for entry in entries.iter() {
+            if entry.is_tick() {
+                entry_tick_height += 1;
+                if num_ticks_left_in_slot == 0 {
+                    num_ticks_left_in_slot = bank.ticks_per_slot();
+                }
+                num_ticks_left_in_slot -= 1;
+            }
+            entries_with_meta.push(EntryMeta {
+                tick_height: entry_tick_height,
+                slot,
+                slot_leader,
+                num_ticks_left_in_slot,
+                parent_slot,
+                entry: entry.clone(),
+            });
+        }
+        forward_entry_sender.send(entries_with_meta)?;
+        Ok(())
+    }
 }
 
 impl Service for ReplayStage {