Merge pull request #18113 from vjpai/cli_streaming_qps

Fix termination condition of streaming callback QPS tests

test/cpp/qps/client_callback.cc

@@ -253,18 +253,20 @@ class CallbackStreamingPingPongReactor final
       : client_(client), ctx_(std::move(ctx)), messages_issued_(0) {}
 
   void StartNewRpc() {
-    if (client_->ThreadCompleted()) return;
     ctx_->stub_->experimental_async()->StreamingCall(&(ctx_->context_), this);
     write_time_ = UsageTimer::Now();
     StartWrite(client_->request());
+    writes_done_started_.clear();
     StartCall();
   }
 
   void OnWriteDone(bool ok) override {
-    if (!ok || client_->ThreadCompleted()) {
-      if (!ok) gpr_log(GPR_ERROR, "Error writing RPC");
+    if (!ok) {
+      gpr_log(GPR_ERROR, "Error writing RPC");
+    }
+    if ((!ok || client_->ThreadCompleted()) &&
+        !writes_done_started_.test_and_set()) {
       StartWritesDone();
-      return;
     }
     StartRead(&ctx_->response_);
   }
@@ -278,7 +280,9 @@ class CallbackStreamingPingPongReactor final
       if (!ok) {
         gpr_log(GPR_ERROR, "Error reading RPC");
       }
+      if (!writes_done_started_.test_and_set()) {
         StartWritesDone();
+      }
       return;
     }
     write_time_ = UsageTimer::Now();
@@ -295,8 +299,6 @@ class CallbackStreamingPingPongReactor final
   }
 
   void ScheduleRpc() {
-    if (client_->ThreadCompleted()) return;
-
     if (!client_->IsClosedLoop()) {
       gpr_timespec next_issue_time = client_->NextRPCIssueTime();
       // Start an alarm callback to run the internal callback after
@@ -312,6 +314,7 @@ class CallbackStreamingPingPongReactor final
 
   CallbackStreamingPingPongClient* client_;
   std::unique_ptr<CallbackClientRpcContext> ctx_;
+  std::atomic_flag writes_done_started_;
   Client::Thread* thread_ptr_;  // Needed to update histogram entries
   double write_time_;           // Track ping-pong round start time
   int messages_issued_;         // Messages issued by this stream