Merge pull request #920 from apolcyn/remove_extra_goroutine_in_benchmark_clients

Remove extra goroutine in benchmark clients

benchmark/worker/benchmark_client.go

@@ -317,28 +317,17 @@ func (bc *benchmarkClient) doCloseLoopStreaming(conns []*grpc.ClientConn, rpcCou
 				// Now relying on worker client to reserve time to do warm up.
 				// The worker client needs to wait for some time after client is created,
 				// before starting benchmark.
-				done := make(chan bool)
 				for {
-					go func() {
 					start := time.Now()
 					if err := doRPC(stream, reqSize, respSize); err != nil {
-							select {
-							case <-bc.stop:
-							case done <- false:
-							}
 						return
 					}
 					elapse := time.Since(start)
 					bc.lockingHistograms[idx].add(int64(elapse))
 					select {
-						case <-bc.stop:
-						case done <- true:
-						}
-					}()
-					select {
 					case <-bc.stop:
 						return
-					case <-done:
+					default:
 					}
 				}
 			}(idx)