From ee16cc77a3118562e85e39f4b9b801dafc3c6d5f Mon Sep 17 00:00:00 2001
From: Carl <carl@solana.com>
Date: Tue, 26 Feb 2019 17:29:38 -0800
Subject: [PATCH] Move last_ids to a simple Hash, unwrap from Arc<RwLock>>

---
 src/replay_stage.rs | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/replay_stage.rs b/src/replay_stage.rs
index 5116bc9af3..8b15a7f6cc 100644
--- a/src/replay_stage.rs
+++ b/src/replay_stage.rs
@@ -62,7 +62,7 @@ impl ReplayStage {
         voting_keypair: &Option<Arc<T>>,
         ledger_entry_sender: &EntrySender,
         current_blob_index: &mut u64,
-        last_entry_id: &Arc<RwLock<Hash>>,
+        last_entry_id: &mut Hash,
         leader_scheduler: &Arc<RwLock<LeaderScheduler>>,
         subscriptions: &Arc<RpcSubscriptions>,
         slot: u64,
@@ -79,7 +79,7 @@ impl ReplayStage {
         let mut num_entries_to_write = entries.len();
         let now = Instant::now();
 
-        if !entries.as_slice().verify(&last_entry_id.read().unwrap()) {
+        if !entries.as_slice().verify(last_entry_id) {
             inc_new_counter_info!("replicate_stage-verify-fail", entries.len());
             return Err(Error::BlobError(BlobError::VerificationFailed));
         }
@@ -155,7 +155,7 @@ 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.write().unwrap() = entries
+        *last_entry_id = entries
             .last()
             .expect("Entries cannot be empty at this point")
             .id;
@@ -206,7 +206,7 @@ impl ReplayStage {
         let subscriptions_ = subscriptions.clone();
 
         // Gather up all the metadata about the current state of the ledger
-        let (mut bank, tick_height, last_entry_id, mut current_blob_index) = {
+        let (mut bank, tick_height, mut last_entry_id, mut current_blob_index) = {
             let mut bank_forks = bank_forks.write().unwrap();
             bank_forks.set_working_bank_id(bank_forks_info[0].bank_id);
             let bank = bank_forks.working_bank();
@@ -219,8 +219,6 @@ impl ReplayStage {
             )
         };
 
-        let last_entry_id = Arc::new(RwLock::new(last_entry_id));
-
         // Update Tpu and other fullnode components with the current bank
         let (mut current_slot, mut current_leader_id, mut max_tick_height_for_slot) = {
             let leader_scheduler = leader_scheduler.read().unwrap();
@@ -248,7 +246,7 @@ impl ReplayStage {
             to_leader_sender
                 .send(TvuRotationInfo {
                     bank: old_bank,
-                    last_entry_id: *last_entry_id.read().unwrap(),
+                    last_entry_id,
                     slot,
                     leader_id,
                 })
@@ -341,7 +339,7 @@ impl ReplayStage {
                             &voting_keypair,
                             &ledger_entry_sender,
                             &mut current_blob_index,
-                            &last_entry_id,
+                            &mut last_entry_id,
                             &leader_scheduler_,
                             &subscriptions_,
                             slot,
@@ -386,7 +384,7 @@ impl ReplayStage {
                             let last_entry = blocktree
                                 .get_slot_entries(slot, meta.last_index, Some(1))
                                 .unwrap();
-                            *(last_entry_id.write().unwrap()) = last_entry[0].id;
+                            last_entry_id = last_entry[0].id;
                         }
 
                         let old_bank = bank.clone();
@@ -419,7 +417,7 @@ impl ReplayStage {
                         to_leader_sender
                             .send(TvuRotationInfo {
                                 bank: old_bank,
-                                last_entry_id: *last_entry_id.read().unwrap(),
+                                last_entry_id,
                                 slot: next_slot,
                                 leader_id,
                             })
@@ -853,7 +851,7 @@ mod test {
         // Set up the cluster info
         let cluster_info_me = Arc::new(RwLock::new(ClusterInfo::new(my_node.info.clone())));
         let (ledger_entry_sender, _ledger_entry_receiver) = channel();
-        let last_entry_id = Hash::default();
+        let mut last_entry_id = Hash::default();
         let mut current_blob_index = 0;
         let mut last_id = Hash::default();
         let mut entries = Vec::new();
@@ -874,7 +872,7 @@ mod test {
             &voting_keypair,
             &ledger_entry_sender,
             &mut current_blob_index,
-            &Arc::new(RwLock::new(last_entry_id)),
+            &mut last_entry_id,
             &leader_scheduler,
             &Arc::new(RpcSubscriptions::default()),
             0,
@@ -902,7 +900,7 @@ mod test {
             &voting_keypair,
             &ledger_entry_sender,
             &mut current_blob_index,
-            &Arc::new(RwLock::new(last_entry_id)),
+            &mut last_entry_id,
             &leader_scheduler,
             &Arc::new(RpcSubscriptions::default()),
             0,