fix a bug about alter affect later than turn on or off

src/observer/mysql/ob_query_response_time.cpp

@@ -175,12 +175,11 @@ int ObRSTCollector::flush_query_response_time(uint64_t tenant_id,const ObString&
 int ObRSTCollector::enable_query_response_time(uint64_t tenant_id){
     int ret = OB_SUCCESS;
     omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
-    if(tenant_config->query_response_time_stats){
-        SERVER_LOG(INFO, "query_response_time_stats already turn on", K(ret), K(tenant_id));
+    ObRSTTimeCollector* time_collector;
+    if (OB_SUCC(collector_map_.get_refactored(tenant_id, time_collector))){
+        SERVER_LOG(WARN, "time collector of the tenant does not exist", K(ret), K(tenant_id));
     } else if (OB_FAIL(collector_map_.set_refactored(tenant_id, new ObRSTTimeCollector()))) {
-        if (OB_HASH_EXIST == ret) {
-            ret = OB_ERR_ALREADY_EXISTS;
-        }
+        SERVER_LOG(WARN, "time collector of the tenant create failed", K(ret), K(tenant_id));
     }
     return ret;
 }
@@ -188,8 +187,11 @@ int ObRSTCollector::enable_query_response_time(uint64_t tenant_id){
 int ObRSTCollector::free_query_response_time(uint64_t tenant_id){
     int ret = OB_SUCCESS;
     omt::ObTenantConfigGuard tenant_config(TENANT_CONF(tenant_id));
-    if (OB_FAIL(collector_map_.erase_refactored(tenant_id))) {
-        SERVER_LOG(WARN,"erase the time collector failed", K(tenant_id));
+    ObRSTTimeCollector* time_collector;
+    if (OB_FAIL(collector_map_.get_refactored(tenant_id, time_collector))){
+        SERVER_LOG(WARN, "time collector of the tenant does not exist", K(ret), K(tenant_id));
+    } else if (OB_FAIL(collector_map_.erase_refactored(tenant_id))) {
+        SERVER_LOG(WARN, "erase the time collector failed", K(tenant_id));
     }
     return ret;
 }