ozone: Add atomic initialization path

ui/ozone/platform/drm/ozone_platform_gbm.cc

 // Copyright 2014 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 "ui/ozone/platform/drm/ozone_platform_gbm.h"
 
 #include <dlfcn.h>
 #include <gbm.h>
 #include <stdlib.h>
 
@@ skipping 71 matching lines @@
     return GbmBuffer::CreateBuffer(gbm, SurfaceFactoryOzone::BGRA_8888, size,
                                    true);
   }
 
  protected:
   DISALLOW_COPY_AND_ASSIGN(GbmBufferGenerator);
 };
 
 class GbmDeviceGenerator : public DrmDeviceGenerator {
  public:
-  GbmDeviceGenerator() {}
+  GbmDeviceGenerator(bool use_atomic) : use_atomic_(use_atomic) {}
   ~GbmDeviceGenerator() override {}
 
   // DrmDeviceGenerator:
   scoped_refptr<DrmDevice> CreateDevice(const base::FilePath& path,
                                         base::File file) override {
     scoped_refptr<DrmDevice> drm = new GbmDevice(path, file.Pass());
-    if (drm->Initialize())
+    if (drm->Initialize(use_atomic_))
       return drm;
 
     return nullptr;
   }
 
  private:
+  bool use_atomic_;
+
   DISALLOW_COPY_AND_ASSIGN(GbmDeviceGenerator);
 };
 
 class OzonePlatformGbm : public OzonePlatform {
  public:
   OzonePlatformGbm(bool use_surfaceless) : use_surfaceless_(use_surfaceless) {}
   ~OzonePlatformGbm() override {}
 
   // OzonePlatform:
   ui::SurfaceFactoryOzone* GetSurfaceFactoryOzone() override {
@@ skipping 47 matching lines @@
 #else
     KeyboardLayoutEngineManager::SetKeyboardLayoutEngine(
         make_scoped_ptr(new StubKeyboardLayoutEngine()));
 #endif
     event_factory_ozone_.reset(new EventFactoryEvdev(
         cursor_.get(), device_manager_.get(),
         KeyboardLayoutEngineManager::GetKeyboardLayoutEngine()));
   }
 
   void InitializeGPU() override {
+    bool use_atomic = base::CommandLine::ForCurrentProcess()->HasSwitch(
+        switches::kOzoneUseAtomicDrm);
 #if defined(OS_CHROMEOS)
     gpu_lock_.reset(new GpuLock());
 #endif
     gl_api_loader_.reset(new GlApiLoader());
     drm_device_manager_.reset(new DrmDeviceManager(
-        scoped_ptr<DrmDeviceGenerator>(new GbmDeviceGenerator())));
+        scoped_ptr<DrmDeviceGenerator>(new GbmDeviceGenerator(use_atomic))));
     buffer_generator_.reset(new GbmBufferGenerator());
     screen_manager_.reset(new ScreenManager(buffer_generator_.get()));
     if (!surface_factory_ozone_)
       surface_factory_ozone_.reset(new GbmSurfaceFactory(use_surfaceless_));
 
     surface_factory_ozone_->InitializeGpu(drm_device_manager_.get(),
                                           screen_manager_.get());
     scoped_ptr<DrmGpuDisplayManager> ndd(new DrmGpuDisplayManager(
         screen_manager_.get(), drm_device_manager_.get()));
     gpu_platform_support_.reset(new DrmGpuPlatformSupport(
@@ skipping 34 matching lines @@
 OzonePlatform* CreateOzonePlatformGbm() {
   base::CommandLine* cmd = base::CommandLine::ForCurrentProcess();
 #if defined(USE_MESA_PLATFORM_NULL)
   // Only works with surfaceless.
   cmd->AppendSwitch(switches::kOzoneUseSurfaceless);
 #endif
   return new OzonePlatformGbm(cmd->HasSwitch(switches::kOzoneUseSurfaceless));
 }
 
 }  // namespace ui