There are some potential feefilter cleanups mentioned and motivated in comment https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-805808485 . If you address the locking one, please be careful and make sure that `round()` is only called under a lock. See https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-807992199

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return;
        }
        CTransactionRef ptx;
        vRecv >> ptx;
        const CTransaction& tx = *ptx;
        const uint256& txid = ptx->GetHash();
        const uint256& wtxid = ptx->GetWitnessHash();
        LOCK2(cs_main, g_cs_orphans);
        CNodeState* nodestate = State(pfrom.GetId());
        const uint256& hash = nodestate->m_wtxid_relay ? wtxid : txid;
        pfrom.AddKnownTx(hash);
        if (nodestate->m_wtxid_relay && txid != wtxid) {
            
            
            
            
            
            pfrom.AddKnownTx(txid);
        }
        m_txrequest.ReceivedResponse(pfrom.GetId(), txid);
        if (tx.HasWitness()) m_txrequest.ReceivedResponse(pfrom.GetId(), wtxid);