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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* Bitcoin Core P2P design
* Running our unit and functional tests

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};
void InitScriptExecutionCache();
bool CheckBlock(const CBlock& block, BlockValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true, bool fCheckMerkleRoot = true);
bool TestBlockValidity(BlockValidationState& state,
                       const CChainParams& chainparams,
                       CChainState& chainstate,
                       const CBlock& block,
                       CBlockIndex* pindexPrev,
                       bool fCheckPOW = true,
                       bool fCheckMerkleRoot = true) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
/** Check whether witness commitments are required for a block, and whether to enforce NULLDUMMY (BIP 147) rules.
 *  Note that transaction witness validation rules are always enforced when P2SH is enforced. */
bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params);
void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
std::vector<unsigned char> GenerateCoinbaseCommitment(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
class CVerifyDB {
public:
    CVerifyDB();
    ~CVerifyDB();
    bool VerifyDB(
        CChainState& chainstate,
        const CChainParams& chainparams,
        CCoinsView& coinsview,
        int nCheckLevel,
        int nCheckDepth) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
};
enum DisconnectResult