Implement about:tracing UI for the sampling profiler (Chromium part)

base/debug/trace_event_unittest.cc

Index: base/debug/trace_event_unittest.cc
diff --git a/base/debug/trace_event_unittest.cc b/base/debug/trace_event_unittest.cc
index b5909845f27c1053b29b68278db598b1e7a14530..1ad53f4c78231f01a75823421a5df4f4f7709147 100644
--- a/base/debug/trace_event_unittest.cc
+++ b/base/debug/trace_event_unittest.cc
@@ -90,6 +90,12 @@ class TraceEventTestFixture : public testing::Test {
                    base::Unretained(this)));
   }
 
+  void FlushContinuousSampling() {
+    TraceLog::GetInstance()->FlushContinuousSamplingTracing(
+        base::Bind(&TraceEventTestFixture::OnTraceDataCollected,
+                   base::Unretained(this)));
+  }
+
   virtual void SetUp() OVERRIDE {
     const char* name = PlatformThread::GetName();
     old_thread_name_ = name ? strdup(name) : NULL;
@@ -1737,6 +1743,56 @@ TEST_F(TraceEventTestFixture, TraceSamplingScope) {
   EndTraceAndFlush();
 }
 
+TEST_F(TraceEventTestFixture, TraceContinuousSampling) {
+  event_watch_notification_ = 0;
+  TraceLog::GetInstance()->SetContinuousSamplingEnabled();
+
+  WaitableEvent* sampled = new WaitableEvent(false, false);
+  TraceLog::GetInstance()->InstallWaitableEventForContinuousSamplingTesting(
+      sampled);
+
+  TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(1, "category", "AAA");
+  sampled->Wait();
+  TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(1, "category", "BBB");
+  sampled->Wait();
+
+  FlushContinuousSampling();
+
+  // Make sure we can get the profiled data.
+  EXPECT_TRUE(FindNamePhase("AAA", "P"));
+  EXPECT_TRUE(FindNamePhase("BBB", "P"));
+
+  Clear();
+
+  TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(1, "category", "CCC");
+  sampled->Wait();
+  TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(1, "category", "DDD");
+  sampled->Wait();
+
+  FlushContinuousSampling();
+
+  // Make sure the profiled data is accumulated.
+  EXPECT_TRUE(FindNamePhase("AAA", "P"));
+  EXPECT_TRUE(FindNamePhase("BBB", "P"));
+  EXPECT_TRUE(FindNamePhase("CCC", "P"));
+  EXPECT_TRUE(FindNamePhase("DDD", "P"));
+
+  Clear();
+
+  TraceLog::GetInstance()->SetContinuousSamplingDisabled();
+
+  FlushContinuousSampling();
+
+  // Make sure disabling the continuous sampling thread clears
+  // the profiled data.
+  EXPECT_FALSE(FindNamePhase("AAA", "P"));
+  EXPECT_FALSE(FindNamePhase("BBB", "P"));
+  EXPECT_FALSE(FindNamePhase("CCC", "P"));
+  EXPECT_FALSE(FindNamePhase("DDD", "P"));
+
+  Clear();
+}
+
 class MyData : public base::debug::ConvertableToTraceFormat {
  public:
   MyData() {}