gpu_perftests: Use zero size gl surface for offscreen rendering

gpu/perftests/texture_upload_perftest.cc

 // Copyright 2015 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.
 
 #include <algorithm>
 #include <vector>
 
 #include "base/containers/small_map.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/stringprintf.h"
 #include "gpu/perftests/measurements.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/perf/perf_test.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_enums.h"
 #include "ui/gl/gl_surface.h"
 #include "ui/gl/gl_version_info.h"
 #include "ui/gl/gpu_timing.h"
 #include "ui/gl/scoped_make_current.h"
 
+#if defined(USE_OZONE)
+#include "base/message_loop/message_loop.h"
+#endif
+
 namespace gpu {
 namespace {
 
 const int kUploadPerfWarmupRuns = 5;
 const int kUploadPerfTestRuns = 30;
 
 #define SHADER(Src) #Src
 
 // clang-format off
 const char kVertexShader[] =
@@ skipping 127 matching lines @@
 }
 
 // PerfTest to check costs of texture upload at different stages
 // on different platforms.
 class TextureUploadPerfTest : public testing::Test {
  public:
   TextureUploadPerfTest() : fbo_size_(1024, 1024) {}
 
   // Overridden from testing::Test
   void SetUp() override {
+#if defined(USE_OZONE)
+    // On Ozone, the backend initializes the event system using a UI
+    // thread.
+    base::MessageLoopForUI main_loop;

[Daniele Castagna, 2015/04/14 15:38:38]

Where in the backend is this message loop used? It'd be nice to avoid this.

[vignatti (out of this project), 2015/04/14 16:39:16]

A few Ozone implementations like the GBM requires early initialization of the
message loop because GL stuff, display management and etc (most of hardware
accesses) happen in the GPU process. So we need the message loop in place
already for the GPU process initial handshake behave correctly.

That said, a couple of weeks ago I've been trying to put an end to all of this,
but it went too far from what I've originally have intended and gave up. More
info here:

https://codereview.chromium.org/1043233003/

+#endif
     static bool gl_initialized = gfx::GLSurface::InitializeOneOff();
     DCHECK(gl_initialized);
     // Initialize an offscreen surface and a gl context.
-    surface_ = gfx::GLSurface::CreateOffscreenGLSurface(gfx::Size(4, 4));
+    surface_ = gfx::GLSurface::CreateOffscreenGLSurface(gfx::Size());
     gl_context_ = gfx::GLContext::CreateGLContext(NULL,  // share_group
                                                   surface_.get(),
                                                   gfx::PreferIntegratedGpu);
     ui::ScopedMakeCurrent smc(gl_context_.get(), surface_.get());
     glGenTextures(1, &color_texture_);
     glBindTexture(GL_TEXTURE_2D, color_texture_);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
@@ skipping 351 matching lines @@
                           gpu_timing_client_->CheckAndResetTimerErrors();
   if (!gpu_timer_errors) {
     upload_and_draw_timers.GetAsMeasurement("upload_and_draw")
         .PrintResult("renaming");
     finish_timers.GetAsMeasurement("finish").PrintResult("renaming");
   }
 }
 
 }  // namespace
 }  // namespace gpu