When i used the encrypted wallet to test transfer parallelly,i frequently got the trouble: The rpc server is not responding.My test script is like below:
#!/bin/sh
while [ 1 ]
do
./bitcoin-cli listaddressgroupings>null
./bitcoin-cli walletpassphrase "!@#$%^&*" 2
./bitcoin sendtoaddress "mhAW6mzs5DeCbzBUHXBi4U446Fdnr1z8U7" 0.01
done

When i open the dead lock trace macro and check the debug log,i found the last print is as below:
2018-12-17 08:27:58 ThreadRPCServer method=walletpassphrase
2018-12-17 08:27:58 LOCKCONTENTION: cs_main
2018-12-17 08:27:58 Locker: wallet/rpcwallet.cpp:2642
2018-12-17 08:27:58 LOCKCONTENTION: pWallet->cs_wallet
2018-12-17 08:27:58 Locker: wallet/rpcwallet.cpp:2607

The line no 2642 is walletpassphrase and 2607 is LockWallet. I checked the code,i found there is no log printed for this line in function "walletpassphrase":
"LogPrint(BCLog::RPC, "queue run of timer %s in %i seconds (using %s)\n", name, nSeconds, timerInterface->Name());" So i guess the reason may be:
When "walletpassphrase" is running and lock the cs_wallet,the last relock timer triggered and call "LockWallet"."LockWallet" want to lock the cs_wallet but it has been locked by "walletpassphrase",so "LockWallet" is blocked.When "walletpassphrase" run to call "RPCRunLater",the function will erase the timer from the std::map "deadlineTimers",but the timer's timeout call is blocked,so the dead lock take place.
Is my guess right?
How to reslove the issue?
Any help will be appreciative！
{
    if (IsValidDestination(dest)) {
        entry.pushKV("address", EncodeDestination(dest));
    }
}
/**
 * List transactions based on the given criteria.
 *
 * @param  pwallet        The wallet.
 * @param  wtx            The wallet transaction.
 * @param  nMinDepth      The minimum confirmation depth.
 * @param  fLong          Whether to include the JSON version of the transaction.
 * @param  ret            The UniValue into which the result is stored.
 * @param  filter_ismine  The "is mine" filter flags.
 * @param  filter_label   Optional label string to filter incoming transactions.
 */
static void ListTransactions(interfaces::Chain::Lock& locked_chain, const CWallet* const pwallet, const CWalletTx& wtx, int nMinDepth, bool fLong, UniValue& ret, const isminefilter& filter_ismine, const std::string* filter_label) EXCLUSIVE_LOCKS_REQUIRED(pwallet->cs_wallet)
{
    CAmount nFee;
    std::list<COutputEntry> listReceived;
    std::list<COutputEntry> listSent;
    wtx.GetAmounts(listReceived, listSent, nFee, filter_ismine);
    bool involvesWatchonly = wtx.IsFromMe(ISMINE_WATCH_ONLY);
    
    if (!filter_label)
    {
        for (const COutputEntry& s : listSent)