Merge bitcoin/bitcoin#26295: Replace global g_cs_orphans lock with local

7082ce3e88d77456d60a5a66bd38807fbd66f311 scripted-diff: rename and de-globalise g_cs_orphans (Anthony Towns)
733d85f79cde353d8c9b54370f296b1031fa33d9 Move all g_cs_orphans locking to txorphanage (Anthony Towns)
a936f41a5d5f7bb97425f82ec64dfae62e840a56 txorphanage: make m_peer_work_set private (Anthony Towns)
3614819864a84ac32f6d53c6ace79b5e71bc174a txorphange: move orphan workset to txorphanage (Anthony Towns)
6f8e442ba61378489a6e2e2ab5bcfbccca1a29ec net_processing: Localise orphan_work_set handling to ProcessOrphanTx (Anthony Towns)
0027174b396cacbaac5fd52f13be3dca9fcbbfb8 net_processing: move ProcessOrphanTx docs to declaration (Anthony Towns)
9910ed755c3dfd7669707b44d993a20030dd7477 net_processing: Pass a Peer& to ProcessOrphanTx (Anthony Towns)
89e2e0da0bcd0b0757d7b42907e2d2214da9f68b net_processing: move extra transactions to msgproc mutex (Anthony Towns)
ff8d44d1967d8ff9fb9b9ea0b87c0470d8cc2550 Remove unnecessary includes of txorphange.h (Anthony Towns)

Pull request description:

  Moves extra transactions to be under the `m_msgproc_mutex` lock rather than `g_cs_orphans` and refactors orphan handling so that the lock can be internal to the `TxOrphange` class.

ACKs for top commit:
  dergoegge:
    Code review ACK 7082ce3e88d77456d60a5a66bd38807fbd66f311
  glozow:
    ACK 7082ce3e88d77456d60a5a66bd38807fbd66f311 via code review and some [basic testing](https://github.com/glozow/bitcoin/blob/review-26295/src/test/orphanage_tests.cpp#L150). I think putting txorphanage in charge of handling peer work sets is the right direction.

Tree-SHA512: 1ec454c3a69ebd45ff652770d6a55c6b183db71aba4d12639ed70f525f0035e069a81d06e9b65b66e87929c607080a1c5e5dcd2ca91eaa2cf202dc6c02aa6818

1 files changed, 34 insertions, 39 deletions

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 0d5be42e0e..346600efd0 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -365,9 +365,6 @@ struct Peer {
     /** Total number of addresses that were processed (excludes rate-limited ones). */
     std::atomic<uint64_t> m_addr_processed{0};
 
-    /** Set of txids to reconsider once their parent transactions have been accepted **/
-    std::set<uint256> m_orphan_work_set GUARDED_BY(g_cs_orphans);
-
     /** Whether we've sent this peer a getheaders in response to an inv prior to initial-headers-sync completing */
     bool m_inv_triggered_getheaders_before_sync GUARDED_BY(NetEventsInterface::g_msgproc_mutex){false};
 
@@ -584,8 +581,17 @@ private:
      */
     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);
+    /**
+     * Reconsider orphan transactions after a parent has been accepted to the mempool.
+     *
+     * @peer[in]  peer     The peer whose orphan transactions we will reconsider. Generally only one
+     *                     orphan will be reconsidered on each call of this function. This set
+     *                     may be added to if accepting an orphan causes its children to be
+     *                     reconsidered.
+     * @return             True if there are still orphans in this peer's work set.
+     */
+    bool ProcessOrphanTx(Peer& peer)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex, cs_main);
     /** Process a single headers message from a peer.
      *
      * @param[in]   pfrom     CNode of the peer
@@ -919,14 +925,14 @@ private:
     /** 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);
@@ -1490,7 +1496,7 @@ void PeerManagerImpl::FinalizeNode(const CNode& node)
     for (const QueuedBlock& entry : state->vBlocksInFlight) {
         mapBlocksInFlight.erase(entry.pindex->GetBlockHash());
     }
-    WITH_LOCK(g_cs_orphans, m_orphanage.EraseForPeer(nodeid));
+    m_orphanage.EraseForPeer(nodeid);
     m_txrequest.DisconnectedPeer(nodeid);
     if (m_txreconciliation) m_txreconciliation->ForgetPeer(nodeid);
     m_num_preferred_download_peers -= state->fPreferredDownload;
@@ -2880,33 +2886,24 @@ void PeerManagerImpl::ProcessHeadersMessage(CNode& pfrom, Peer& peer,
     return;
 }
 
-/**
- * Reconsider orphan transactions after a parent has been accepted to the mempool.
- *
- * @param[in,out]  orphan_work_set  The set of orphan transactions to reconsider. Generally only one
- *                                  orphan will be reconsidered on each call of this function. This set
- *                                  may be added to if accepting an orphan causes its children to be
- *                                  reconsidered.
- */
-void PeerManagerImpl::ProcessOrphanTx(std::set<uint256>& orphan_work_set)
+bool PeerManagerImpl::ProcessOrphanTx(Peer& peer)
 {
+    AssertLockHeld(g_msgproc_mutex);
     AssertLockHeld(cs_main);
-    AssertLockHeld(g_cs_orphans);
-
-    while (!orphan_work_set.empty()) {
-        const uint256 orphanHash = *orphan_work_set.begin();
-        orphan_work_set.erase(orphan_work_set.begin());
 
-        const auto [porphanTx, from_peer] = m_orphanage.GetTx(orphanHash);
-        if (porphanTx == nullptr) continue;
+    CTransactionRef porphanTx = nullptr;
+    NodeId from_peer = -1;
+    bool more = false;
 
+    while (CTransactionRef porphanTx = m_orphanage.GetTxToReconsider(peer.m_id, from_peer, more)) {
         const MempoolAcceptResult result = m_chainman.ProcessTransaction(porphanTx);
         const TxValidationState& state = result.m_state;
+        const uint256& orphanHash = porphanTx->GetHash();
 
         if (result.m_result_type == MempoolAcceptResult::ResultType::VALID) {
             LogPrint(BCLog::MEMPOOL, "   accepted orphan tx %s\n", orphanHash.ToString());
             RelayTransaction(orphanHash, porphanTx->GetWitnessHash());
-            m_orphanage.AddChildrenToWorkSet(*porphanTx, orphan_work_set);
+            m_orphanage.AddChildrenToWorkSet(*porphanTx, peer.m_id);
             m_orphanage.EraseTx(orphanHash);
             for (const CTransactionRef& removedTx : result.m_replaced_transactions.value()) {
                 AddToCompactExtraTransactions(removedTx);
@@ -2957,6 +2954,8 @@ void PeerManagerImpl::ProcessOrphanTx(std::set<uint256>& orphan_work_set)
             break;
         }
     }
+
+    return more;
 }
 
 bool PeerManagerImpl::PrepareBlockFilterRequest(CNode& node, Peer& peer,
@@ -3990,7 +3989,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
             AddKnownTx(*peer, txid);
         }
 
-        LOCK2(cs_main, g_cs_orphans);
+        LOCK(cs_main);
 
         m_txrequest.ReceivedResponse(pfrom.GetId(), txid);
         if (tx.HasWitness()) m_txrequest.ReceivedResponse(pfrom.GetId(), wtxid);
@@ -4031,7 +4030,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
             m_txrequest.ForgetTxHash(tx.GetHash());
             m_txrequest.ForgetTxHash(tx.GetWitnessHash());
             RelayTransaction(tx.GetHash(), tx.GetWitnessHash());
-            m_orphanage.AddChildrenToWorkSet(tx, peer->m_orphan_work_set);
+            m_orphanage.AddChildrenToWorkSet(tx, peer->m_id);
 
             pfrom.m_last_tx_time = GetTime<std::chrono::seconds>();
 
@@ -4045,7 +4044,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
             }
 
             // Recursively process any orphan transactions that depended on this one
-            ProcessOrphanTx(peer->m_orphan_work_set);
+            ProcessOrphanTx(*peer);
         }
         else if (state.GetResult() == TxValidationResult::TX_MISSING_INPUTS)
         {
@@ -4226,7 +4225,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
         bool fBlockReconstructed = false;
 
         {
-        LOCK2(cs_main, g_cs_orphans);
+        LOCK(cs_main);
         // If AcceptBlockHeader returned true, it set pindex
         assert(pindex);
         UpdateBlockAvailability(pfrom.GetId(), pindex->GetBlockHash());
@@ -4854,16 +4853,17 @@ bool PeerManagerImpl::ProcessMessages(CNode* pfrom, std::atomic<bool>& interrupt
         }
     }
 
+    bool has_more_orphans;
     {
-        LOCK2(cs_main, g_cs_orphans);
-        if (!peer->m_orphan_work_set.empty()) {
-            ProcessOrphanTx(peer->m_orphan_work_set);
-        }
+        LOCK(cs_main);
+        has_more_orphans = ProcessOrphanTx(*peer);
     }
 
     if (pfrom->fDisconnect)
         return false;
 
+    if (has_more_orphans) return true;
+
     // this maintains the order of responses
     // and prevents m_getdata_requests to grow unbounded
     {
@@ -4871,11 +4871,6 @@ bool PeerManagerImpl::ProcessMessages(CNode* pfrom, std::atomic<bool>& interrupt
         if (!peer->m_getdata_requests.empty()) return true;
     }
 
-    {
-        LOCK(g_cs_orphans);
-        if (!peer->m_orphan_work_set.empty()) return true;
-    }
-
     // Don't bother if send buffer is too full to respond anyway
     if (pfrom->fPauseSend) return false;