Add mutext protection for stop flag

src/wal/src/walMgmt.c

@@ -36,9 +36,16 @@ static int32_t  walInitObj(SWal *pWal);
 static void     walFreeObj(void *pWal);
 
 int32_t walInit() {
+  int32_t code = 0;
   tsWal.refId = taosOpenRef(TSDB_MIN_VNODES, walFreeObj);
 
-  int32_t code = walCreateThread();
+  code = pthread_mutex_init(&tsWal.mutex, NULL);
+  if (code) {
+    wError("failed to init wal mutex since %s", tstrerror(code));
+    return code;
+  }
+
+  code = walCreateThread();
   if (code != TSDB_CODE_SUCCESS) {
     wError("failed to init wal module since %s", tstrerror(code));
     return code;
@@ -51,6 +58,7 @@ int32_t walInit() {
 void walCleanUp() {
   walStopThread();
   taosCloseRef(tsWal.refId);
+  pthread_mutex_destroy(&tsWal.mutex);
   wInfo("wal module is cleaned up");
 }
 
@@ -183,10 +191,15 @@ static void walFsyncAll() {
 }
 
 static void *walThreadFunc(void *param) {
+  int stop = 0;
   while (1) {
     walUpdateSeq();
     walFsyncAll();
-    if (tsWal.stop) break;
+
+    pthread_mutex_lock(&tsWal.mutex);
+    stop = tsWal.stop;
+    pthread_mutex_unlock(&tsWal.mutex);
+    if (stop) break;
   }
 
   return NULL;
@@ -209,7 +222,10 @@ static int32_t walCreateThread() {
 }
 
 static void walStopThread() {
+  pthread_mutex_lock(&tsWal.mutex);
   tsWal.stop = 1;
+  pthread_mutex_unlock(&tsWal.mutex);
+
   if (taosCheckPthreadValid(tsWal.thread)) {
     pthread_join(tsWal.thread, NULL);
   }