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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{
    
    CRITICAL = 2,
    
    LARGE = 1,
    OK = 0
};
/**
 * CChainState stores and provides an API to update our local knowledge of the
 * current best chain.
 *
 * Eventually, the API here is targeted at being exposed externally as a
 * consumable libconsensus library, so any functions added must only call
 * other class member functions, pure functions in other parts of the consensus
 * library, callbacks via the validation interface, or read/write-to-disk
 * functions (eventually this will also be via callbacks).
 *
 * Anything that is contingent on the current tip of the chain is stored here,
 * whereas block information and metadata independent of the current tip is
 * kept in `BlockMetadataManager`.
 */
class CChainState