Merge pull request #3744 from taosdata/patch/TD-1645

remove a race condition in TCP socket

go @ 8c58c512

-Subproject commit 567b7b12f3fd2775c718d284beffc8c38dd6c219
+Subproject commit 8c58c512b6acda8bcdfa48fdc7140227b5221766

src/rpc/src/rpcTcp.c

@@ -62,7 +62,7 @@ typedef struct {
   char        label[TSDB_LABEL_LEN];
   int         numOfThreads;
   void *      shandle;
-  SThreadObj *pThreadObj;
+  SThreadObj **pThreadObj;
   pthread_t   thread;
 } SServerObj;
 
@@ -90,7 +90,7 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
   tstrncpy(pServerObj->label, label, sizeof(pServerObj->label));
   pServerObj->numOfThreads = numOfThreads;
 
-  pServerObj->pThreadObj = (SThreadObj *)calloc(sizeof(SThreadObj), numOfThreads);
+  pServerObj->pThreadObj = (SThreadObj **)calloc(sizeof(SThreadObj *), numOfThreads);
   if (pServerObj->pThreadObj == NULL) {
     tError("TCP:%s no enough memory", label);
     terrno = TAOS_SYSTEM_ERROR(errno); 
@@ -104,19 +104,28 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
   pthread_attr_setdetachstate(&thattr, PTHREAD_CREATE_JOINABLE);
 
   // initialize parameters in case it may encounter error later 
-  pThreadObj = pServerObj->pThreadObj;
   for (int i = 0; i < numOfThreads; ++i) {
+    pThreadObj = (SThreadObj *)calloc(sizeof(SThreadObj), 1);
+    if (pThreadObj == NULL) {
+      tError("TCP:%s no enough memory", label);
+      terrno = TAOS_SYSTEM_ERROR(errno); 
+      for (int j=0; j<i; ++j) free(pServerObj->pThreadObj[j]);
+      free(pServerObj->pThreadObj);
+      free(pServerObj);
+      return NULL;
+    }
+      
+    pServerObj->pThreadObj[i] = pThreadObj;
     pThreadObj->pollFd = -1;
     taosResetPthread(&pThreadObj->thread);
     pThreadObj->processData = fp;
     tstrncpy(pThreadObj->label, label, sizeof(pThreadObj->label));
     pThreadObj->shandle = shandle;
-    pThreadObj++;
   }
 
   // initialize mutex, thread, fd which may fail
-  pThreadObj = pServerObj->pThreadObj;
   for (int i = 0; i < numOfThreads; ++i) {
+    pThreadObj = pServerObj->pThreadObj[i];
     code = pthread_mutex_init(&(pThreadObj->mutex), NULL);
     if (code < 0) {
       tError("%s failed to init TCP process data mutex(%s)", label, strerror(errno));
@@ -137,7 +146,6 @@ void *taosInitTcpServer(uint32_t ip, uint16_t port, char *label, int numOfThread
     }
 
     pThreadObj->threadId = i;
-    pThreadObj++;
   }
 
   pServerObj->fd = taosOpenTcpServerSocket(pServerObj->ip, pServerObj->port);
@@ -166,6 +174,11 @@ static void taosStopTcpThread(SThreadObj* pThreadObj) {
   pThreadObj->stop = true;
   eventfd_t fd = -1;
 
+  if (taosComparePthread(pThreadObj->thread, pthread_self())) {
+    pthread_detach(pthread_self());
+    return;
+  }
+
   if (taosCheckPthreadValid(pThreadObj->thread) && pThreadObj->pollFd >= 0) {
     // signal the thread to stop, try graceful method first,
     // and use pthread_cancel when failed
@@ -183,15 +196,11 @@ static void taosStopTcpThread(SThreadObj* pThreadObj) {
     }
   }
 
-  if (taosCheckPthreadValid(pThreadObj->thread)) pthread_join(pThreadObj->thread, NULL);
-  if (pThreadObj->pollFd >=0) taosCloseSocket(pThreadObj->pollFd);
-  if (fd != -1) taosCloseSocket(fd);
-
-  while (pThreadObj->pHead) {
-    SFdObj *pFdObj = pThreadObj->pHead;
-    pThreadObj->pHead = pFdObj->next;
-    taosFreeFdObj(pFdObj);
+  if (taosCheckPthreadValid(pThreadObj->thread) && pThreadObj->pollFd >= 0) {
+     pthread_join(pThreadObj->thread, NULL);
   }
+
+  if (fd != -1) taosCloseSocket(fd);
 }
 
 void taosStopTcpServer(void *handle) {
@@ -199,7 +208,14 @@ void taosStopTcpServer(void *handle) {
 
   if (pServerObj == NULL) return;
   if(pServerObj->fd >=0) shutdown(pServerObj->fd, SHUT_RD);
-  if (taosCheckPthreadValid(pServerObj->thread)) pthread_join(pServerObj->thread, NULL);
+
+  if (taosCheckPthreadValid(pServerObj->thread)) {
+    if (taosComparePthread(pServerObj->thread, pthread_self())) {
+      pthread_detach(pthread_self());
+    } else {
+      pthread_join(pServerObj->thread, NULL);
+    }
+  }
 
   tDebug("%s TCP server is stopped", pServerObj->label);
 }
@@ -210,9 +226,8 @@ void taosCleanUpTcpServer(void *handle) {
   if (pServerObj == NULL) return;
 
   for (int i = 0; i < pServerObj->numOfThreads; ++i) {
-    pThreadObj = pServerObj->pThreadObj + i;
+    pThreadObj = pServerObj->pThreadObj[i];
     taosStopTcpThread(pThreadObj);
-    pthread_mutex_destroy(&(pThreadObj->mutex));
   }
 
   tDebug("%s TCP server is cleaned up", pServerObj->label);
@@ -249,7 +264,7 @@ static void *taosAcceptTcpConnection(void *arg) {
     taosSetSockOpt(connFd, SOL_SOCKET, SO_RCVTIMEO, &to, sizeof(to));
 
     // pick up the thread to handle this connection
-    pThreadObj = pServerObj->pThreadObj + threadId;
+    pThreadObj = pServerObj->pThreadObj[threadId];
 
     SFdObj *pFdObj = taosMallocFdObj(pThreadObj, connFd);
     if (pFdObj) {
@@ -329,8 +344,6 @@ void taosCleanUpTcpClient(void *chandle) {
 
   taosStopTcpThread(pThreadObj);
   tDebug ("%s TCP client is cleaned up", pThreadObj->label);
-
-  taosTFree(pThreadObj);
 }
 
 void *taosOpenTcpClientConnection(void *shandle, void *thandle, uint32_t ip, uint16_t port) {
@@ -503,8 +516,22 @@ static void *taosProcessTcpData(void *param) {
       pFdObj->thandle = (*(pThreadObj->processData))(&recvInfo);
       if (pFdObj->thandle == NULL) taosFreeFdObj(pFdObj);
     }
+
+    if (pThreadObj->stop) break; 
+  }
+
+  if (pThreadObj->pollFd >=0) taosCloseSocket(pThreadObj->pollFd);
+
+  while (pThreadObj->pHead) {
+    SFdObj *pFdObj = pThreadObj->pHead;
+    pThreadObj->pHead = pFdObj->next;
+    taosFreeFdObj(pFdObj);
   }
 
+  pthread_mutex_destroy(&(pThreadObj->mutex));
+  tDebug("%s TCP thread exits ...", pThreadObj->label);
+  taosTFree(pThreadObj);
+
   return NULL;
 }
 

src/sync/src/taosTcpPool.c

@@ -219,7 +219,10 @@ static void *taosProcessTcpData(void *param) {
           continue;
         }
       }
+
     }
+
+    if (pThread->stop) break;
   }
 
   uDebug("%p TCP epoll thread exits", pThread);
@@ -321,5 +324,5 @@ static void taosStopPoolThread(SThreadObj *pThread) {
   }
 
   pthread_join(thread, NULL);
-  taosClose(fd);
+  if (fd >= 0) taosClose(fd);
 }