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;
    }
    if (msg_type == NetMsgType::FILTERCLEAR) {
        if (!(pfrom.GetLocalServices() & NODE_BLOOM)) {
            LogPrint(BCLog::NET, "filterclear received despite not offering bloom services from peer=%d; disconnecting\n", pfrom.GetId());
            pfrom.fDisconnect = true;
            return;
        }
        if (pfrom.m_tx_relay == nullptr) {
            return;
        }
        LOCK(pfrom.m_tx_relay->cs_filter);
        pfrom.m_tx_relay->pfilter = nullptr;
        pfrom.m_tx_relay->fRelayTxes = true;
        return;
    }
    if (msg_type == NetMsgType::FEEFILTER) {
        CAmount newFeeFilter = 0;
        vRecv >> newFeeFilter;
        if (MoneyRange(newFeeFilter)) {
            if (pfrom.m_tx_relay != nullptr) {
                pfrom.m_tx_relay->minFeeFilter = newFeeFilter;
            }
            LogPrint(BCLog::NET, "received: feefilter of %s from peer=%d\n", CFeeRate(newFeeFilter).ToString(), pfrom.GetId());
        }
        return;
    }
    if (msg_type == NetMsgType::GETCFILTERS) {
        ProcessGetCFilters(pfrom, vRecv);