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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} else {
                
                fRevertToHeaderProcessing = true;
            }
        }
        } 
        if (fProcessBLOCKTXN) {
            return ProcessMessage(pfrom, NetMsgType::BLOCKTXN, blockTxnMsg, time_received, interruptMsgProc);
        }
        if (fRevertToHeaderProcessing) {
            
            
            
            
            
            return ProcessHeadersMessage(pfrom, *peer, {cmpctblock.header}, true);
        }
        if (fBlockReconstructed) {
            
            
            {
                LOCK(cs_main);
                mapBlockSource.emplace(pblock->GetHash(), std::make_pair(pfrom.GetId(), false));
            }