From fcf950d6f478d6674ae071b4c69bfff69e89fc9f Mon Sep 17 00:00:00 2001
From: Stan Kladko <13399135+kladkogex@users.noreply.github.com>
Date: Mon, 22 Jul 2024 13:55:39 +0100
Subject: [PATCH] #1545 state locking

---
 libethereum/Client.cpp    |  3 +--
 libethereum/SkaleHost.cpp |  6 +++---
 libskale/State.cpp        | 18 ++----------------
 libskale/State.h          |  7 -------
 4 files changed, 6 insertions(+), 28 deletions(-)

diff --git a/libethereum/Client.cpp b/libethereum/Client.cpp
index 03efbb03f..8a8193745 100644
--- a/libethereum/Client.cpp
+++ b/libethereum/Client.cpp
@@ -1076,8 +1076,7 @@ Block Client::blockByNumber( BlockNumber _h ) const {
         }
 
         // blockByNumber is only used for reads
-
-        auto readState = m_state.createStateCopyWithReadLock();
+        auto readState = m_state.createStateCopyAndClearCaches();
         readState.mutableHistoricState().setRootByBlockNumber( _h );
         // removed m_blockImportMutex here
         // this function doesn't interact with latest block so the mutex isn't needed
diff --git a/libethereum/SkaleHost.cpp b/libethereum/SkaleHost.cpp
index d3c985524..ca2c21e66 100644
--- a/libethereum/SkaleHost.cpp
+++ b/libethereum/SkaleHost.cpp
@@ -449,9 +449,9 @@ ConsensusExtFace::transactions_vector SkaleHost::pendingTransactions(
             if ( tx.verifiedOn < m_lastBlockWithBornTransactions )
                 try {
                     bool isMtmEnabled = m_client.chainParams().sChain.multiTransactionMode;
-                    Executive::verifyTransaction(tx, latestInfo.timestamp(), latestInfo,
-                                                 m_client.state().createStateCopyWithReadLock(), m_client.chainParams(), 0,
-                                                 getGasPrice(), isMtmEnabled );
+                    Executive::verifyTransaction( tx, latestInfo.timestamp(), latestInfo,
+                        m_client.state().createReadOnlySnapBasedCopy(), m_client.chainParams(), 0,
+                        getGasPrice(), isMtmEnabled );
                 } catch ( const exception& ex ) {
                     if ( to_delete.count( tx.sha3() ) == 0 )
                         clog( VerbosityInfo, "skale-host" )
diff --git a/libskale/State.cpp b/libskale/State.cpp
index 454e04443..fb47ee6fc 100644
--- a/libskale/State.cpp
+++ b/libskale/State.cpp
@@ -91,7 +91,7 @@ State::State( dev::u256 const& _accountStartNonce, boost::filesystem::path const
     m_db_ptr = make_shared< OverlayDB >( openDB( _dbPath, _genesis,
         _bs == BaseState::PreExisting ? dev::WithExisting::Trust : dev::WithExisting::Kill ) );
 
-    auto state = createStateCopyWithReadLock();
+    auto state = createStateCopyAndClearCaches();
     totalStorageUsed_ = state.storageUsedTotal();
 #ifdef HISTORIC_STATE
     m_historicState.setRootFromDB();
@@ -123,7 +123,7 @@ State::State( u256 const& _accountStartNonce, OverlayDB const& _db,
       m_historicState( _accountStartNonce, _historicDb, _historicBlockToStateRootDb, _bs )
 #endif
 {
-    auto state = createStateCopyWithReadLock();
+    auto state = createStateCopyAndClearCaches();
     totalStorageUsed_ = state.storageUsedTotal();
 #ifdef HISTORIC_STATE
     m_historicState.setRootFromDB();
@@ -246,9 +246,6 @@ State::State( const State& _s )
 #endif
 {
     x_db_ptr = _s.x_db_ptr;
-    if ( _s.m_db_read_lock ) {
-        m_db_read_lock.emplace( *x_db_ptr );
-    }
     m_db_ptr = _s.m_db_ptr;
     m_orig_db = _s.m_orig_db;
     m_cache = _s.m_cache;
@@ -266,9 +263,6 @@ State::State( const State& _s )
 
 State& State::operator=( const State& _s ) {
     x_db_ptr = _s.x_db_ptr;
-    if ( _s.m_db_read_lock ) {
-        m_db_read_lock.emplace( *x_db_ptr );
-    }
     m_db_ptr = _s.m_db_ptr;
     m_orig_db = _s.m_orig_db;
     m_cache = _s.m_cache;
@@ -901,13 +895,6 @@ void State::clearAllCaches() {
 }
 
 
-State State::createStateCopyWithReadLock() const {
-    LDB_CHECK(!m_isReadOnlySnapBasedState);
-    State stateCopy = State( *this );
-    stateCopy.m_db_read_lock.emplace( *stateCopy.x_db_ptr );
-    stateCopy.clearCaches();
-    return stateCopy;
-}
 
 State State::createStateCopyAndClearCaches() const {
     LDB_CHECK(!m_isReadOnlySnapBasedState);
@@ -928,7 +915,6 @@ State State::createReadOnlySnapBasedCopy() const {
     stateCopy.m_snap = m_orig_db->getLastBlockSnap();
     LDB_CHECK( stateCopy.m_snap )
     // the state does not use any locking since it is based on db snapshot
-    stateCopy.m_db_read_lock = boost::none;
     stateCopy.x_db_ptr = nullptr;
     stateCopy.m_db_ptr = make_shared< OverlayDB >(
         make_unique< batched_io::read_only_snap_based_batched_db >( stateCopy.m_orig_db, stateCopy.m_snap ) );
diff --git a/libskale/State.h b/libskale/State.h
index 7a93c0359..46ed65e9d 100644
--- a/libskale/State.h
+++ b/libskale/State.h
@@ -380,11 +380,6 @@ class State {
 
     ChangeLog const& changeLog() const { return m_changeLog; }
 
-    /// Create State copy with read locked state db
-    /// since the lock the db is unlocked
-
-    State createStateCopyWithReadLock() const;
-
     /// Create State copy to modify data.
     State createStateCopyAndClearCaches() const;
 
@@ -482,8 +477,6 @@ class State {
 private:
     enum Auxiliary { CODE = 1 };
 
-    boost::optional< boost::shared_lock< boost::shared_mutex > > m_db_read_lock;
-
     std::shared_ptr< boost::shared_mutex > x_db_ptr;
     std::shared_ptr< OverlayDB > m_db_ptr;  ///< Our overlay for the state.
     std::shared_ptr< OverlayFS > m_fs_ptr;  ///< Our overlay for the file system operations.