fix logical bug, optimize code

paddle/fluid/operators/listen_and_serv_op.cc

@@ -130,10 +130,15 @@ void ListenAndServOp::RunSyncLoop(
 
   int32_t profile_step = 0;
   while (true) {
-    if (FLAGS_listen_and_serv_profile_period > 0 && profile_step == 0) {
+    PADDLE_ENFORCE_LE(profile_step, FLAGS_listen_and_serv_profile_period,
+                      "profile_step should not be larger then "
+                      "FLAGS_listen_and_serv_profile_period");
+    if (FLAGS_listen_and_serv_profile_period > 0) {
+      if (profile_step == 0) {
         auto pf_state = paddle::platform::ProfilerState::kCPU;
         paddle::platform::EnableProfiler(pf_state);
       }
+    }
     // Get from multiple trainers, we don't care about the order in which
     // the gradients arrives, just add suffix 0~n and merge the gradient.
     rpc_service_->SetCond(distributed::kRequestSend);
@@ -175,14 +180,15 @@ void ListenAndServOp::RunSyncLoop(
     // reset received sparse vars to avoid reuse it in the next mini-batch
     dynamic_cast<distributed::RequestSendHandler *>(request_send_handler_.get())
         ->ResetSparseVarRecorder();
-    if (FLAGS_listen_and_serv_profile_period > 0 &&
-        profile_step == FLAGS_listen_and_serv_profile_period) {
+    if (FLAGS_listen_and_serv_profile_period > 0) {
+      if (profile_step == FLAGS_listen_and_serv_profile_period) {
         paddle::platform::DisableProfiler(
             paddle::platform::EventSortingKey::kTotal, "/dev/null");
         profile_step = 0;
       } else {
         profile_step++;
       }
+    }
   }  // while(true)
 }