Merge #19604: Pass mempool pointer to UnloadBlockIndex/GetCoinsCacheSizeState

fae8c28dae747f9c4c6481049742346d18202fc8 Pass mempool pointer to GetCoinsCacheSizeState (MarcoFalke)
fac674db200e6b2d5b32069335fb24e713d7b69f Pass mempool pointer to UnloadBlockIndex (MarcoFalke)
faec851b6eb7e65e28cdcae50d6dc86fafa0f91c test: Simplify cs_main locks (MarcoFalke)

Pull request description:

  Split out from #19556

  Instead of relying on the implicit mempool global, pass a mempool pointer (which can be `0`). This helps with testing, code clarity and unlocks the features described in #19556.

ACKs for top commit:
  jnewbery:
    code review ACK fae8c28dae747f9c4c6481049742346d18202fc8
  fjahr:
    Code review ACK fae8c28dae747f9c4c6481049742346d18202fc8
  darosior:
    Tested ACK fae8c28dae747f9c4c6481049742346d18202fc8
  jamesob:
    ACK fae8c28dae747f9c4c6481049742346d18202fc8 ([`jamesob/ackr/19604.1.MarcoFalke.pass_mempool_pointer_to`](https://github.com/jamesob/bitcoin/tree/ackr/19604.1.MarcoFalke.pass_mempool_pointer_to))

Tree-SHA512: fa687518c8cda4a095bdbdfe56e01fae2fb16c13d51efbb1312cd6dc007611fc47f53f475602e4a843e3973c9410e6af5a81d6847bd2399f8262ca7205975728

8 files changed, 27 insertions, 36 deletions

diff --git a/src/init.cpp b/src/init.cpp
index ad500702d7..6cca21f375 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1567,7 +1567,7 @@ bool AppInitMain(const util::Ref& context, NodeContext& node)
                 chainman.m_total_coinstip_cache = nCoinCacheUsage;
                 chainman.m_total_coinsdb_cache = nCoinDBCache;
 
-                UnloadBlockIndex();
+                UnloadBlockIndex(node.mempool);
 
                 // new CBlockTreeDB tries to delete the existing file, which
                 // fails if it's still open from the previous loop. Close it first:
diff --git a/src/qt/test/apptests.cpp b/src/qt/test/apptests.cpp
index 443e2d047d..b880a99baf 100644
--- a/src/qt/test/apptests.cpp
+++ b/src/qt/test/apptests.cpp
@@ -83,7 +83,7 @@ void AppTests::appTests()
     // Reset global state to avoid interfering with later tests.
     LogInstance().DisconnectTestLogger();
     AbortShutdown();
-    UnloadBlockIndex();
+    UnloadBlockIndex(/* mempool */ nullptr);
     WITH_LOCK(::cs_main, g_chainman.Reset());
 }
 
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 0cd991f453..14f65dcb7c 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -182,9 +182,9 @@ TestingSetup::~TestingSetup()
     m_node.connman.reset();
     m_node.banman.reset();
     m_node.args = nullptr;
+    UnloadBlockIndex(m_node.mempool);
     m_node.mempool = nullptr;
     m_node.scheduler.reset();
-    UnloadBlockIndex();
     m_node.chainman->Reset();
     m_node.chainman = nullptr;
     pblocktree.reset();
diff --git a/src/test/validation_chainstate_tests.cpp b/src/test/validation_chainstate_tests.cpp
index f531b393b8..2076a1096a 100644
--- a/src/test/validation_chainstate_tests.cpp
+++ b/src/test/validation_chainstate_tests.cpp
@@ -34,9 +34,7 @@ BOOST_AUTO_TEST_CASE(validation_chainstate_resize_caches)
         return outp;
     };
 
-    ENTER_CRITICAL_SECTION(cs_main);
-    CChainState& c1 = manager.InitializeChainstate();
-    LEAVE_CRITICAL_SECTION(cs_main);
+    CChainState& c1 = *WITH_LOCK(cs_main, return &manager.InitializeChainstate());
     c1.InitCoinsDB(
         /* cache_size_bytes */ 1 << 23, /* in_memory */ true, /* should_wipe */ false);
     WITH_LOCK(::cs_main, c1.InitCoinsCache(1 << 23));
diff --git a/src/test/validation_chainstatemanager_tests.cpp b/src/test/validation_chainstatemanager_tests.cpp
index f99191b08f..887a48124f 100644
--- a/src/test/validation_chainstatemanager_tests.cpp
+++ b/src/test/validation_chainstatemanager_tests.cpp
@@ -54,10 +54,7 @@ BOOST_AUTO_TEST_CASE(chainstatemanager)
 
     // Create a snapshot-based chainstate.
     //
-    ENTER_CRITICAL_SECTION(cs_main);
-    CChainState& c2 = *WITH_LOCK(::cs_main,
-        return &manager.InitializeChainstate(GetRandHash()));
-    LEAVE_CRITICAL_SECTION(cs_main);
+    CChainState& c2 = *WITH_LOCK(::cs_main, return &manager.InitializeChainstate(GetRandHash()));
     chainstates.push_back(&c2);
     c2.InitCoinsDB(
         /* cache_size_bytes */ 1 << 23, /* in_memory */ true, /* should_wipe */ false);
@@ -115,9 +112,7 @@ BOOST_AUTO_TEST_CASE(chainstatemanager_rebalance_caches)
 
     // Create a legacy (IBD) chainstate.
     //
-    ENTER_CRITICAL_SECTION(cs_main);
-    CChainState& c1 = manager.InitializeChainstate();
-    LEAVE_CRITICAL_SECTION(cs_main);
+    CChainState& c1 = *WITH_LOCK(cs_main, return &manager.InitializeChainstate());
     chainstates.push_back(&c1);
     c1.InitCoinsDB(
         /* cache_size_bytes */ 1 << 23, /* in_memory */ true, /* should_wipe */ false);
@@ -134,9 +129,7 @@ BOOST_AUTO_TEST_CASE(chainstatemanager_rebalance_caches)
 
     // Create a snapshot-based chainstate.
     //
-    ENTER_CRITICAL_SECTION(cs_main);
-    CChainState& c2 = manager.InitializeChainstate(GetRandHash());
-    LEAVE_CRITICAL_SECTION(cs_main);
+    CChainState& c2 = *WITH_LOCK(cs_main, return &manager.InitializeChainstate(GetRandHash()));
     chainstates.push_back(&c2);
     c2.InitCoinsDB(
         /* cache_size_bytes */ 1 << 23, /* in_memory */ true, /* should_wipe */ false);
diff --git a/src/test/validation_flush_tests.cpp b/src/test/validation_flush_tests.cpp
index 7111fc3380..8bac914f05 100644
--- a/src/test/validation_flush_tests.cpp
+++ b/src/test/validation_flush_tests.cpp
@@ -56,7 +56,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
 
     // Without any coins in the cache, we shouldn't need to flush.
     BOOST_CHECK_EQUAL(
-        chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
+        chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
         CoinsCacheSizeState::OK);
 
     // If the initial memory allocations of cacheCoins don't match these common
@@ -71,7 +71,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
         }
 
         BOOST_CHECK_EQUAL(
-            chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
+            chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
             CoinsCacheSizeState::CRITICAL);
 
         BOOST_TEST_MESSAGE("Exiting cache flush tests early due to unsupported arch");
@@ -92,7 +92,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
         print_view_mem_usage(view);
         BOOST_CHECK_EQUAL(view.AccessCoin(res).DynamicMemoryUsage(), COIN_SIZE);
         BOOST_CHECK_EQUAL(
-            chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
+            chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
             CoinsCacheSizeState::OK);
     }
 
@@ -100,26 +100,26 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
     for (int i{0}; i < 4; ++i) {
         add_coin(view);
         print_view_mem_usage(view);
-        if (chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0) ==
+        if (chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0) ==
             CoinsCacheSizeState::CRITICAL) {
             break;
         }
     }
 
     BOOST_CHECK_EQUAL(
-        chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
+        chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 0),
         CoinsCacheSizeState::CRITICAL);
 
     // Passing non-zero max mempool usage should allow us more headroom.
     BOOST_CHECK_EQUAL(
-        chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
+        chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
         CoinsCacheSizeState::OK);
 
     for (int i{0}; i < 3; ++i) {
         add_coin(view);
         print_view_mem_usage(view);
         BOOST_CHECK_EQUAL(
-            chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
+            chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, /*max_mempool_size_bytes*/ 1 << 10),
             CoinsCacheSizeState::OK);
     }
 
@@ -135,7 +135,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
         BOOST_CHECK(usage_percentage >= 0.9);
         BOOST_CHECK(usage_percentage < 1);
         BOOST_CHECK_EQUAL(
-            chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, 1 << 10),
+            chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, 1 << 10),
             CoinsCacheSizeState::LARGE);
     }
 
@@ -143,7 +143,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
     for (int i{0}; i < 1000; ++i) {
         add_coin(view);
         BOOST_CHECK_EQUAL(
-            chainstate.GetCoinsCacheSizeState(tx_pool),
+            chainstate.GetCoinsCacheSizeState(&tx_pool),
             CoinsCacheSizeState::OK);
     }
 
@@ -151,7 +151,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
     // preallocated memory that doesn't get reclaimed even after flush.
 
     BOOST_CHECK_EQUAL(
-        chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, 0),
+        chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, 0),
         CoinsCacheSizeState::CRITICAL);
 
     view.SetBestBlock(InsecureRand256());
@@ -159,7 +159,7 @@ BOOST_AUTO_TEST_CASE(getcoinscachesizestate)
     print_view_mem_usage(view);
 
     BOOST_CHECK_EQUAL(
-        chainstate.GetCoinsCacheSizeState(tx_pool, MAX_COINS_CACHE_BYTES, 0),
+        chainstate.GetCoinsCacheSizeState(&tx_pool, MAX_COINS_CACHE_BYTES, 0),
         CoinsCacheSizeState::CRITICAL);
 }
 
diff --git a/src/validation.cpp b/src/validation.cpp
index 545aa0f2d3..3cebf1090e 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2227,7 +2227,7 @@ bool CChainState::ConnectBlock(const CBlock& block, BlockValidationState& state,
     return true;
 }
 
-CoinsCacheSizeState CChainState::GetCoinsCacheSizeState(const CTxMemPool& tx_pool)
+CoinsCacheSizeState CChainState::GetCoinsCacheSizeState(const CTxMemPool* tx_pool)
 {
     return this->GetCoinsCacheSizeState(
         tx_pool,
@@ -2236,11 +2236,11 @@ CoinsCacheSizeState CChainState::GetCoinsCacheSizeState(const CTxMemPool& tx_poo
 }
 
 CoinsCacheSizeState CChainState::GetCoinsCacheSizeState(
-    const CTxMemPool& tx_pool,
+    const CTxMemPool* tx_pool,
     size_t max_coins_cache_size_bytes,
     size_t max_mempool_size_bytes)
 {
-    int64_t nMempoolUsage = tx_pool.DynamicMemoryUsage();
+    const int64_t nMempoolUsage = tx_pool ? tx_pool->DynamicMemoryUsage() : 0;
     int64_t cacheSize = CoinsTip().DynamicMemoryUsage();
     int64_t nTotalSpace =
         max_coins_cache_size_bytes + std::max<int64_t>(max_mempool_size_bytes - nMempoolUsage, 0);
@@ -2279,7 +2279,7 @@ bool CChainState::FlushStateToDisk(
     {
         bool fFlushForPrune = false;
         bool fDoFullFlush = false;
-        CoinsCacheSizeState cache_state = GetCoinsCacheSizeState(::mempool);
+        CoinsCacheSizeState cache_state = GetCoinsCacheSizeState(&::mempool);
         LOCK(cs_LastBlockFile);
         if (fPruneMode && (fCheckForPruning || nManualPruneHeight > 0) && !fReindex) {
             if (nManualPruneHeight > 0) {
@@ -4587,13 +4587,13 @@ void CChainState::UnloadBlockIndex() {
 // May NOT be used after any connections are up as much
 // of the peer-processing logic assumes a consistent
 // block index state
-void UnloadBlockIndex()
+void UnloadBlockIndex(CTxMemPool* mempool)
 {
     LOCK(cs_main);
     g_chainman.Unload();
     pindexBestInvalid = nullptr;
     pindexBestHeader = nullptr;
-    mempool.clear();
+    if (mempool) mempool->clear();
     vinfoBlockFile.clear();
     nLastBlockFile = 0;
     setDirtyBlockIndex.clear();
diff --git a/src/validation.h b/src/validation.h
index 53503768aa..534162d64a 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -160,7 +160,7 @@ void LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, FlatFi
 /** Ensures we have a genesis block in the block tree, possibly writing one to disk. */
 bool LoadGenesisBlock(const CChainParams& chainparams);
 /** Unload database information */
-void UnloadBlockIndex();
+void UnloadBlockIndex(CTxMemPool* mempool);
 /** Run an instance of the script checking thread */
 void ThreadScriptCheck(int worker_num);
 /**
@@ -674,11 +674,11 @@ public:
     //! Dictates whether we need to flush the cache to disk or not.
     //!
     //! @return the state of the size of the coins cache.
-    CoinsCacheSizeState GetCoinsCacheSizeState(const CTxMemPool& tx_pool)
+    CoinsCacheSizeState GetCoinsCacheSizeState(const CTxMemPool* tx_pool)
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 
     CoinsCacheSizeState GetCoinsCacheSizeState(
-        const CTxMemPool& tx_pool,
+        const CTxMemPool* tx_pool,
         size_t max_coins_cache_size_bytes,
         size_t max_mempool_size_bytes) EXCLUSIVE_LOCKS_REQUIRED(::cs_main);