masterEntry change possible race-condition

src/main/java/org/redisson/connection/MasterSlaveEntry.java

@@ -125,17 +125,19 @@ public class MasterSlaveEntry {
     }
 
     public RedisConnection connectionWriteOp() {
-        acquireMasterConnection();
+        // may changed during changeMaster call
+        ConnectionEntry entry = masterEntry;
+        acquireMasterConnection(entry);
 
-        RedisConnection conn = masterEntry.getConnections().poll();
+        RedisConnection conn = entry.getConnections().poll();
         if (conn != null) {
             return conn;
         }
 
         try {
-            return masterEntry.connect(config);
+            return entry.connect(config);
         } catch (RedisException e) {
-            masterEntry.getConnectionsSemaphore().release();
+            entry.getConnectionsSemaphore().release();
             throw e;
         }
     }
@@ -148,11 +150,11 @@ public class MasterSlaveEntry {
         return slaveBalancer.nextPubSubConnection();
     }
 
-    void acquireMasterConnection() {
-        if (!masterEntry.getConnectionsSemaphore().tryAcquire()) {
+    void acquireMasterConnection(ConnectionEntry entry) {
+        if (!entry.getConnectionsSemaphore().tryAcquire()) {
             log.warn("Master connection pool gets exhausted! Trying to acquire connection ...");
             long time = System.currentTimeMillis();
-            masterEntry.getConnectionsSemaphore().acquireUninterruptibly();
+            entry.getConnectionsSemaphore().acquireUninterruptibly();
             long endTime = System.currentTimeMillis() - time;
             log.warn("Master connection acquired, time spended: {} ms", endTime);
         }
@@ -164,13 +166,14 @@ public class MasterSlaveEntry {
 
     public void releaseWrite(RedisConnection connection) {
         // may changed during changeMaster call
-        if (!masterEntry.getClient().equals(connection.getRedisClient())) {
+        ConnectionEntry entry = masterEntry;
+        if (!entry.getClient().equals(connection.getRedisClient())) {
             connection.closeAsync();
             return;
         }
 
-        masterEntry.getConnections().add(connection);
-        masterEntry.getConnectionsSemaphore().release();
+        entry.getConnections().add(connection);
+        entry.getConnectionsSemaphore().release();
     }
 
     public void releaseRead(RedisConnection сonnection) {