Added unit tests for the GPU Tracer.

gpu/command_buffer/service/gpu_tracer.cc

Index: gpu/command_buffer/service/gpu_tracer.cc
diff --git a/gpu/command_buffer/service/gpu_tracer.cc b/gpu/command_buffer/service/gpu_tracer.cc
index d7cd1b8b747957e2599c60b95eb418f39fb8f6d6..cd0f6619f99a20f22824dadb743783aed5afe062 100644
--- a/gpu/command_buffer/service/gpu_tracer.cc
+++ b/gpu/command_buffer/service/gpu_tracer.cc
@@ -18,6 +18,16 @@ namespace gles2 {
 static const unsigned int kProcessInterval = 16;
 static TraceOutputter* g_outputter_thread = NULL;
 
+CPUTime::CPUTime() {
+}
+
+int64 CPUTime::GetCurrentTime() {
+  return base::TimeTicks::NowFromSystemTraceTime().ToInternalValue();
+}
+
+CPUTime::~CPUTime() {
+}
+
 TraceMarker::TraceMarker(const std::string& category, const std::string& name)
     : category_(category),
       name_(name),
@@ -42,10 +52,10 @@ TraceOutputter::TraceOutputter(const std::string& name)
 
 TraceOutputter::~TraceOutputter() { g_outputter_thread = NULL; }
 
-void TraceOutputter::Trace(const std::string& category,
-                           const std::string& name,
-                           int64 start_time,
-                           int64 end_time) {
+void TraceOutputter::TraceDevice(const std::string& category,
+                                 const std::string& name,
+                                 int64 start_time,
+                                 int64 end_time) {
   TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP0(category.c_str(),
                                                     name.c_str(),
                                                     local_trace_id_,
@@ -59,7 +69,20 @@ void TraceOutputter::Trace(const std::string& category,
   ++local_trace_id_;
 }
 
+void TraceOutputter::TraceServiceBegin(const std::string& category,
+                                       const std::string& name,
+                                       void* id) {
+  TRACE_EVENT_COPY_ASYNC_BEGIN0(category.c_str(), name.c_str(), id);

[vmiura, 2015/01/07 00:40:56]

Using dynamic category strings isn't working right.  Are you planning to land
that fix after?

[David Yen, 2015/01/07 18:11:47]

Yes, that change is still in the other CL where gl_category is also added:
https://codereview.chromium.org/813573003/

+}
+
+void TraceOutputter::TraceServiceEnd(const std::string& category,
+                                     const std::string& name,
+                                     void* id) {
+  TRACE_EVENT_COPY_ASYNC_END0(category.c_str(), name.c_str(), id);
+}
+
 GPUTrace::GPUTrace(scoped_refptr<Outputter> outputter,
+                   scoped_refptr<CPUTime> cpu_time,
                    const std::string& category,
                    const std::string& name,
                    int64 offset,
@@ -67,6 +90,7 @@ GPUTrace::GPUTrace(scoped_refptr<Outputter> outputter,
     : category_(category),
       name_(name),
       outputter_(outputter),
+      cpu_time_(cpu_time),
       offset_(offset),
       start_time_(0),
       end_time_(0),
@@ -98,7 +122,7 @@ GPUTrace::~GPUTrace() {
 
 void GPUTrace::Start(bool trace_service) {
   if (trace_service) {
-    TRACE_EVENT_COPY_ASYNC_BEGIN0(category().c_str(), name().c_str(), this);
+    outputter_->TraceServiceBegin(category_, name_, this);
   }
 
   switch (tracer_type_) {
@@ -115,7 +139,7 @@ void GPUTrace::Start(bool trace_service) {
       if (offset_ == 0) {
         GLint64 gl_now = 0;
         glGetInteger64v(GL_TIMESTAMP, &gl_now);
-        offset_ = base::TimeTicks::NowFromSystemTraceTime().ToInternalValue() -
+        offset_ = cpu_time_->GetCurrentTime() -
                   gl_now / base::Time::kNanosecondsPerMicrosecond;
       }
       // Intentionally fall through to kTracerTypeARBTimer case.xs
@@ -140,7 +164,7 @@ void GPUTrace::End(bool tracing_service) {
   }
 
   if (tracing_service) {
-    TRACE_EVENT_COPY_ASYNC_END0(category().c_str(), name().c_str(), this);
+    outputter_->TraceServiceEnd(category_, name_, this);
   }
 }
 
@@ -175,7 +199,7 @@ void GPUTrace::Process() {
   start_time_ = (begin_stamp / base::Time::kNanosecondsPerMicrosecond) +
                 offset_;
   end_time_ = (end_stamp / base::Time::kNanosecondsPerMicrosecond) + offset_;
-  outputter_->Trace(category(), name(), start_time_, end_time_);
+  outputter_->TraceDevice(category(), name(), start_time_, end_time_);
 }
 
 GPUTracer::GPUTracer(gles2::GLES2Decoder* decoder)
@@ -190,13 +214,6 @@ GPUTracer::GPUTracer(gles2::GLES2Decoder* decoder)
       gpu_timing_synced_(false),
       gpu_executing_(false),
       process_posted_(false) {
-  if (gfx::g_driver_gl.ext.b_GL_EXT_disjoint_timer_query) {
-    tracer_type_ = kTracerTypeDisjointTimer;
-    outputter_ = TraceOutputter::Create("GL_EXT_disjoint_timer_query");
-  } else if (gfx::g_driver_gl.ext.b_GL_ARB_timer_query) {
-    tracer_type_ = kTracerTypeARBTimer;
-    outputter_ = TraceOutputter::Create("GL_ARB_timer_query");
-  }
 }
 
 GPUTracer::~GPUTracer() {
@@ -206,6 +223,28 @@ bool GPUTracer::BeginDecoding() {
   if (gpu_executing_)
     return false;
 
+  if (outputter_ == NULL) {
+    tracer_type_ = DetermineTracerType();
+    const char* tracer_type_name = "Unknown";
+    switch (tracer_type_) {
+      case kTracerTypeDisjointTimer:
+        tracer_type_name = "GL_EXT_disjoint_timer_query";
+        break;
+      case kTracerTypeARBTimer:
+        tracer_type_name = "GL_ARB_timer_query";
+        break;
+
+      default:
+        break;
+    }
+
+    outputter_ = CreateOutputter(tracer_type_name);
+  }
+
+  if (cpu_time_ == NULL) {
+    cpu_time_ = CreateCPUTime();
+  }
+
   CalculateTimerOffset();
   gpu_executing_ = true;
 
@@ -327,7 +366,33 @@ scoped_refptr<GPUTrace> GPUTracer::CreateTrace(const std::string& category,
   GpuTracerType tracer_type = *gpu_trace_dev_category ? tracer_type_ :
                                                         kTracerTypeInvalid;
 
-  return new GPUTrace(outputter_, category, name, timer_offset_, tracer_type);
+  return new GPUTrace(outputter_, cpu_time_, category, name,
+                      timer_offset_, tracer_type);
+}
+
+scoped_refptr<Outputter> GPUTracer::CreateOutputter(const std::string& name) {
+  return TraceOutputter::Create(name);
+}
+
+scoped_refptr<CPUTime> GPUTracer::CreateCPUTime() {
+  return new CPUTime();
+}
+
+GpuTracerType GPUTracer::DetermineTracerType() {
+  if (gfx::g_driver_gl.ext.b_GL_EXT_disjoint_timer_query) {
+    return kTracerTypeDisjointTimer;
+  } else if (gfx::g_driver_gl.ext.b_GL_ARB_timer_query) {
+    return kTracerTypeARBTimer;
+  }
+
+  return kTracerTypeInvalid;
+}
+
+void GPUTracer::PostTask() {
+  base::MessageLoop::current()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&GPUTracer::Process, base::AsWeakPtr(this)),
+      base::TimeDelta::FromMilliseconds(kProcessInterval));
 }
 
 void GPUTracer::Process() {
@@ -345,7 +410,7 @@ void GPUTracer::ProcessTraces() {
   TRACE_EVENT0("gpu", "GPUTracer::ProcessTraces");
 
   // Make owning decoder's GL context current
-  if (!decoder_->MakeCurrent()) {
+  if (decoder_ && !decoder_->MakeCurrent()) {

[vmiura, 2015/01/07 00:40:56]

Should the tests use a mock decoder instead?

[David Yen, 2015/01/07 18:11:48]

Done.

     // Skip subsequent GL calls if MakeCurrent fails
     traces_.clear();
     return;
@@ -401,10 +466,8 @@ void GPUTracer::CalculateTimerOffset() {
     glGetQueryObjectui64v(query, GL_QUERY_RESULT, &gl_now);
     glDeleteQueriesARB(1, &query);
 
-    base::TimeTicks system_now = base::TimeTicks::NowFromSystemTraceTime();
-
     gl_now /= base::Time::kNanosecondsPerMicrosecond;
-    timer_offset_ = system_now.ToInternalValue() - gl_now;
+    timer_offset_ = cpu_time_->GetCurrentTime() - gl_now;
     gpu_timing_synced_ = true;
   }
 }
@@ -414,10 +477,7 @@ void GPUTracer::IssueProcessTask() {
     return;
 
   process_posted_ = true;
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&GPUTracer::Process, base::AsWeakPtr(this)),
-      base::TimeDelta::FromMilliseconds(kProcessInterval));
+  PostTask();
 }
 
 }  // namespace gles2