Add perf tests for async waits using base::MessageLoop.

mojo/environment/async_wait_perftest.cc

Index: mojo/environment/async_wait_perftest.cc
diff --git a/mojo/environment/async_wait_perftest.cc b/mojo/environment/async_wait_perftest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8614b8557c0de9fc5fb37119a8469825e8c71231
--- /dev/null
+++ b/mojo/environment/async_wait_perftest.cc
@@ -0,0 +1,78 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file has perf tests for async waits using |base::MessageLoop| (i.e., the
+// "Chromium" |Environment|).
+
+#include <stdint.h>
+
+#include <functional>
+#include <memory>
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "base/strings/stringprintf.h"
+#include "base/test/perf_log.h"
+#include "base/time/time.h"
+#include "mojo/message_pump/message_pump_mojo.h"
+#include "mojo/public/c/environment/tests/async_waiter_perftest_helpers.h"
+#include "mojo/public/cpp/environment/environment.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace mojo {
+namespace {
+
+constexpr int64_t kPerftestTimeMicroseconds = 3 * 1000000;
+
+void QuitMessageLoopNow() {
+  base::MessageLoop::current()->QuitNow();
+}
+
+void SingleThreadedTestHelper(
+    const char* name,
+    std::function<std::unique_ptr<base::MessageLoop>()> make_message_loop) {
+  for (uint32_t num_handles = 1u; num_handles <= 10000u; num_handles *= 10u) {
+    auto message_loop = make_message_loop();
+
+    base::TimeTicks start_time;
+    base::TimeTicks end_time;
+    uint64_t raw_result = test::DoAsyncWaiterPerfTest(
+        Environment::GetDefaultAsyncWaiter(), num_handles,
+        [&start_time, &end_time]() {
+          base::MessageLoop::current()->PostDelayedTask(
+              FROM_HERE, base::Bind(&QuitMessageLoopNow),
+              base::TimeDelta::FromMicroseconds(kPerftestTimeMicroseconds));
+          start_time = base::TimeTicks::Now();
+          base::MessageLoop::current()->Run();
+          end_time = base::TimeTicks::Now();
+        });
+
+    double result =
+        static_cast<double>(raw_result) / (end_time - start_time).InSecondsF();
+    base::LogPerfResult(
+        base::StringPrintf("%s/%u", name, static_cast<unsigned>(num_handles))
+            .c_str(),
+        result, "callbacks/second");
+  }
+}
+
+TEST(AsyncWaitPerfTest, SingleThreaded_DefaultMessagePump) {
+  SingleThreadedTestHelper(
+      "AsyncWaitPerfTest.SingleThreaded_DefaultMessagePump", []() {
+        return std::unique_ptr<base::MessageLoop>(new base::MessageLoop());
+      });
+}
+
+TEST(AsyncWaitPerfTest, SingleThreaded_MessagePumpMojo) {
+  SingleThreadedTestHelper(
+      "AsyncWaitPerfTest.SingleThreaded_MessagePumpMojo", []() {
+        return std::unique_ptr<base::MessageLoop>(new base::MessageLoop(
+            make_scoped_ptr(new common::MessagePumpMojo())));
+      });
+}
+
+}  // namespace
+}  // namespace mojo