write conflict vs commited 错误

如果是start_ts < commit_ts，错误码不应该是write conflict吗？
另外在看tikv源码时，看到了一部分关于committed错误的源码：

pub fn check_txn_status_missing_lock(
    txn: &mut MvccTxn,
    reader: &mut SnapshotReader<impl Snapshot>,
    primary_key: Key,
    mismatch_lock: Option<Lock>,
    action: MissingLockAction,
    resolving_pessimistic_lock: bool,
) -> Result<TxnStatus> {
    MVCC_CHECK_TXN_STATUS_COUNTER_VEC.get_commit_info.inc();
 
    match reader.get_txn_commit_record(&primary_key)? {
        TxnCommitRecord::SingleRecord { commit_ts, write } => {
            if write.write_type == WriteType::Rollback {
                Ok(TxnStatus::RolledBack)
            } else {
                Ok(TxnStatus::committed(commit_ts))
            }
        }

...

    fn get_txn_commit_record(&mut self, key: &Key, start_ts: TimeStamp) -> Result<TxnCommitRecord> {
        // It's possible a txn with a small `start_ts` has a greater `commit_ts` than a
        // txn with a greater `start_ts` in pessimistic transaction.
        // I.e., txn_1.commit_ts > txn_2.commit_ts > txn_2.start_ts > txn_1.start_ts.
        //
        // Scan all the versions from `TimeStamp::max()` to `start_ts`.
        let mut seek_ts = TimeStamp::max();
        let mut gc_fence = TimeStamp::from(0);
        while let Some((commit_ts, write)) = self.seek_write(key, seek_ts)? {
            if write.start_ts == start_ts {
                return Ok(TxnCommitRecord::SingleRecord { commit_ts, write });
            }

可以看到在这里面，当write表的start_ts = 当前事务的start_ts，且不是rollback的才会反这个错误，不过其他地方可能也会反这个错误。