rpc did not handle simeple request head in right way if its session is already closed in server

coverity scan defect for tqueue.c

src/common/src/tglobal.c

@@ -43,7 +43,7 @@ int16_t  tsNumOfTotalVnodes = TSDB_INVALID_VNODE_NUM;
 int32_t  tsNumOfMnodes = 3;
 
 // common
-int32_t tsRpcTimer = 300;
+int32_t tsRpcTimer = 1000;
 int32_t tsRpcMaxTime = 600;  // seconds;
 int32_t tsMaxShellConns = 5000;
 int32_t tsMaxConnections = 5000;

src/rpc/src/rpcMain.c

@@ -665,6 +665,12 @@ static SRpcConn *rpcAllocateServerConn(SRpcInfo *pRpc, SRecvInfo *pRecv) {
     return pConn;
   }
 
+  // if code is not 0, it means it is simple reqhead, just ignore
+  if (pHead->code != 0) {
+    terrno = TSDB_CODE_RPC_ALREADY_PROCESSED;
+    return NULL;
+  }
+
   int sid = taosAllocateId(pRpc->idPool);
   if (sid <= 0) {
     tError("%s maximum number of sessions:%d is reached", pRpc->label, pRpc->sessions);

src/rpc/src/rpcTcp.c

@@ -419,7 +419,7 @@ static int taosReadTcpData(SFdObj *pFdObj, SRecvInfo *pInfo) {
     tError("%s %p TCP malloc(size:%d) fail", pThreadObj->label, pFdObj->thandle, msgLen);
     return -1;
   } else {
-    // tDebug("malloc mem: %p", buffer);
+    tDebug("TCP malloc mem: %p", buffer);
   }
 
   msg = buffer + tsRpcOverhead;

src/rpc/src/rpcUdp.c

@@ -212,7 +212,7 @@ static void *taosRecvUdpData(void *param) {
       tError("%s failed to allocate memory, size:%ld", pConn->label, dataLen);
       continue;
     } else {
-      // tTrace("malloc mem: %p", tmsg);
+      tDebug("UDP malloc mem: %p", tmsg);
     }
 
     tmsg += tsRpcOverhead;  // overhead for SRpcReqContext

src/util/src/tqueue.c

@@ -68,10 +68,15 @@ void taosCloseQueue(taos_queue param) {
   if (param == NULL) return;
   STaosQueue *queue = (STaosQueue *)param;
   STaosQnode *pTemp;
+  STaosQset  *qset;
+
+  pthread_mutex_lock(&queue->mutex);
   STaosQnode *pNode = queue->head;  
   queue->head = NULL;
+  qset = queue->qset;
+  pthread_mutex_unlock(&queue->mutex);
 
-  if (queue->qset) taosRemoveFromQset(queue->qset, queue); 
+  if (queue->qset) taosRemoveFromQset(qset, queue); 
 
   pthread_mutex_lock(&queue->mutex);