diff --git a/src/gausskernel/storage/ipc/procarray.cpp b/src/gausskernel/storage/ipc/procarray.cpp
index 4e97936cf..794fa7821 100644
--- a/src/gausskernel/storage/ipc/procarray.cpp
+++ b/src/gausskernel/storage/ipc/procarray.cpp
@@ -4674,6 +4674,8 @@ TransactionId ListAllSessionGttFrozenxids(int maxSize, ThreadId *pids, Transacti
     }
 
     ThreadPoolSessControl *sessCtrl = g_threadPoolControler->GetSessionCtrl();
+    AutoMutexLock alock(sessCtrl->GetSessionCtrlLock());
+    alock.lock();
     const knl_sess_control *sessList = sessCtrl->GetSessionList();
     const knl_sess_control *currSess = sessList;
     while (currSess != nullptr) {
@@ -4694,6 +4696,7 @@ TransactionId ListAllSessionGttFrozenxids(int maxSize, ThreadId *pids, Transacti
         }
         currSess = currSess->next;
     }
+    alock.unLock();
 
     if (maxSize > 0) {
         *n = i;
diff --git a/src/include/threadpool/threadpool_sessctl.h b/src/include/threadpool/threadpool_sessctl.h
index d035e0437..b8c6c88e0 100644
--- a/src/include/threadpool/threadpool_sessctl.h
+++ b/src/include/threadpool/threadpool_sessctl.h
@@ -88,9 +88,9 @@ public:
         return m_activelist;
     }
 
-    inline pthread_mutex_t GetSessionCtrlLock()
+    inline pthread_mutex_t* GetSessionCtrlLock()
     {
-        return m_sessCtrlock;
+        return &m_sessCtrlock;
     }
 
 private: