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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pfrom.m_bip152_highbandwidth_from = fAnnounceUsingCMPCTBLOCK;
            }
            if (!State(pfrom.GetId())->fSupportsDesiredCmpctVersion) {
                if (pfrom.GetLocalServices() & NODE_WITNESS)
                    State(pfrom.GetId())->fSupportsDesiredCmpctVersion = (nCMPCTBLOCKVersion == 2);
                else
                    State(pfrom.GetId())->fSupportsDesiredCmpctVersion = (nCMPCTBLOCKVersion == 1);
            }
        }
        return;
    }
    
    
    if (msg_type == NetMsgType::WTXIDRELAY) {
        if (pfrom.fSuccessfullyConnected) {
            
            LogPrint(BCLog::NET, "wtxidrelay received after verack from peer=%d; disconnecting\n", pfrom.GetId());
            pfrom.fDisconnect = true;
            return;
        }
        if (pfrom.GetCommonVersion() >= WTXID_RELAY_VERSION) {
            LOCK(cs_main);
            if (!State(pfrom.GetId())->m_wtxid_relay) {
                State(pfrom.GetId())->m_wtxid_relay = true;
                m_wtxid_relay_peers++;
            } else {
                LogPrint(BCLog::NET, "ignoring duplicate wtxidrelay from peer=%d\n", pfrom.GetId());
            }
        } else {
            LogPrint(BCLog::NET, "ignoring wtxidrelay due to old common version=%d from peer=%d\n", pfrom.GetCommonVersion(), pfrom.GetId());