Merge bitcoin/bitcoin#27270: refactor, net processing: Avoid CNode::m_relays_txs usage

55c4795 [net processing] Use TxRelay::m_relay_txs over CNode::m_relays_txs (dergoegge)

Pull request description:

  `CNode::m_relays_txs` is meant to only be used for the eviction logic in `net`. `TxRelay::m_relay_txs` will hold the same value and is meant to be used on the application layer to determine if we will/should relay transactions to a peer.

  (Shameless plug: we should really better specify the interface for updating eviction data to avoid refactors like this in the future -> #25572)

ACKs for top commit:
  MarcoFalke:
    lgtm ACK 55c4795

Tree-SHA512: 59cfd23e32568fd96cda5570790e518242a6c76d4edf5b7d1a2a7f9724d590d2a38395504e05be0af4e98dd5c0056fc0be6568eab2818934692483a186e5181d

Author: fanquake

src/net_processing.cpp

@@ -3296,11 +3296,13 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
         if (greatest_common_version >= WTXID_RELAY_VERSION && m_txreconciliation) {
             // Per BIP-330, we announce txreconciliation support if:
             // - protocol version per the peer's VERSION message supports WTXID_RELAY;
-            // - transaction relay is supported per the peer's VERSION message (see m_relays_txs);
-            // - this is not a block-relay-only connection and not a feeler (see m_relays_txs);
+            // - transaction relay is supported per the peer's VERSION message
+            // - this is not a block-relay-only connection and not a feeler
             // - this is not an addr fetch connection;
             // - we are not in -blocksonly mode.
-            if (pfrom.m_relays_txs && !pfrom.IsAddrFetchConn() && !m_ignore_incoming_txs) {
+            const auto* tx_relay = peer->GetTxRelay();
+            if (tx_relay && WITH_LOCK(tx_relay->m_bloom_filter_mutex, return tx_relay->m_relay_txs) &&
+                !pfrom.IsAddrFetchConn() && !m_ignore_incoming_txs) {
                 const uint64_t recon_salt = m_txreconciliation->PreRegisterPeer(pfrom.GetId());
                 m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::SENDTXRCNCL,
                                                              TXRECONCILIATION_VERSION, recon_salt));
@@ -3528,7 +3530,8 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
         // Peer must not offer us reconciliations if they specified no tx relay support in VERSION.
         // This flag might also be false in other cases, but the RejectIncomingTxs check above
         // eliminates them, so that this flag fully represents what we are looking for.
-        if (!pfrom.m_relays_txs) {
+        const auto* tx_relay = peer->GetTxRelay();
+        if (!tx_relay || !WITH_LOCK(tx_relay->m_bloom_filter_mutex, return tx_relay->m_relay_txs)) {
             LogPrintLevel(BCLog::NET, BCLog::Level::Debug, "sendtxrcncl received from peer=%d which indicated no tx relay to us; disconnecting\n", pfrom.GetId());
             pfrom.fDisconnect = true;
             return;