net_processing: move extra transactions to msgproc mutex

Previously vExtraTxnForCompact and vExtraTxnForCompactIt were protected
by g_cs_orphans; protect them by g_msgproc_mutex instead, as they
are only used during message processing.

Author: ajtowns

src/net_processing.cpp

@@ -590,7 +590,7 @@ class PeerManagerImpl final : public PeerManager
     bool MaybeDiscourageAndDisconnect(CNode& pnode, Peer& peer);
 
     void ProcessOrphanTx(std::set<uint256>& orphan_work_set) EXCLUSIVE_LOCKS_REQUIRED(cs_main, g_cs_orphans)
-        EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex);
+        EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex);
     /** Process a single headers message from a peer.
      *
      * @param[in]   pfrom     CNode of the peer
@@ -924,14 +924,14 @@ class PeerManagerImpl final : public PeerManager
     /** Storage for orphan information */
     TxOrphanage m_orphanage;
 
-    void AddToCompactExtraTransactions(const CTransactionRef& tx) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans);
+    void AddToCompactExtraTransactions(const CTransactionRef& tx) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex);
 
     /** Orphan/conflicted/etc transactions that are kept for compact block reconstruction.
      *  The last -blockreconstructionextratxn/DEFAULT_BLOCK_RECONSTRUCTION_EXTRA_TXN of
      *  these are kept in a ring buffer */
-    std::vector<std::pair<uint256, CTransactionRef>> vExtraTxnForCompact GUARDED_BY(g_cs_orphans);
+    std::vector<std::pair<uint256, CTransactionRef>> vExtraTxnForCompact GUARDED_BY(g_msgproc_mutex);
     /** Offset into vExtraTxnForCompact to insert the next tx */
-    size_t vExtraTxnForCompactIt GUARDED_BY(g_cs_orphans) = 0;
+    size_t vExtraTxnForCompactIt GUARDED_BY(g_msgproc_mutex) = 0;
 
     /** Check whether the last unknown block a peer advertised is not yet known. */
     void ProcessBlockAvailability(NodeId nodeid) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
@@ -2885,6 +2885,7 @@ void PeerManagerImpl::ProcessHeadersMessage(CNode& pfrom, Peer& peer,
  */
 void PeerManagerImpl::ProcessOrphanTx(std::set<uint256>& orphan_work_set)
 {
+    AssertLockHeld(g_msgproc_mutex);
     AssertLockHeld(cs_main);
     AssertLockHeld(g_cs_orphans);
 

src/txorphanage.h

@@ -10,7 +10,7 @@
 #include <primitives/transaction.h>
 #include <sync.h>
 
-/** Guards orphan transactions and extra txs for compact blocks */
+/** Guards orphan transactions */
 extern RecursiveMutex g_cs_orphans;
 
 /** A class to track orphan transactions (failed on TX_MISSING_INPUTS)