ozone: Implement zero/one-copy texture for Ozone GBM.

cc/resources/resource_provider.cc

Index: cc/resources/resource_provider.cc
diff --git a/cc/resources/resource_provider.cc b/cc/resources/resource_provider.cc
index f081f6236f87a36410537af4a9c0e570f1191510..a039818bd5f5ef7dcb2d2970e9019163a699cddf 100644
--- a/cc/resources/resource_provider.cc
+++ b/cc/resources/resource_provider.cc
@@ -957,13 +957,6 @@ ResourceProvider::ScopedWriteLockGpuMemoryBuffer::
     GLES2Interface* gl = resource_provider_->ContextGL();
     DCHECK(gl);
 
-#if defined(OS_CHROMEOS)

[reveman, 2015/06/25 14:07:51]

we should just remove this. if there are still performance issues with using
fences then we need to solve them.

-    // TODO(reveman): GL_COMMANDS_ISSUED_CHROMIUM is used for synchronization
-    // on ChromeOS to avoid some performance issues. This only works with
-    // shared memory backed buffers. crbug.com/436314
-    DCHECK_EQ(gpu_memory_buffer_->GetHandle().type, gfx::SHARED_MEMORY_BUFFER);
-#endif
-
     resource_->image_id = gl->CreateImageCHROMIUM(
         gpu_memory_buffer_->AsClientBuffer(), size_.width(), size_.height(),
         GLInternalFormat(resource_->format));
@@ -1865,15 +1858,17 @@ void ResourceProvider::CopyResource(ResourceId source_id,
     if (!source_resource->gl_read_lock_query_id)
       gl->GenQueriesEXT(1, &source_resource->gl_read_lock_query_id);
 #if defined(OS_CHROMEOS)
-    // TODO(reveman): This avoids a performance problem on some ChromeOS
-    // devices. This needs to be removed to support native GpuMemoryBuffer
-    // implementations. crbug.com/436314
-    gl->BeginQueryEXT(GL_COMMANDS_ISSUED_CHROMIUM,
-                      source_resource->gl_read_lock_query_id);
-#else
+    // TODO(reveman): GL_COMMANDS_ISSUED_CHROMIUM is used for synchronization
+    // on ChromeOS to avoid some performance issues. This only works with
+    // shared memory backed buffers. crbug.com/436314
+    if (source_resource->gpu_memory_buffer->GetHandle().type ==
+        gfx::SHARED_MEMORY_BUFFER)
+      gl->BeginQueryEXT(GL_COMMANDS_ISSUED_CHROMIUM,
+                        source_resource->gl_read_lock_query_id);
+    else

[dshwang, 2015/06/25 14:52:13]

This quirk is for ARM ChromeOS perf issue.
After this CL, only SHARED_MEMORY_BUFFER on ChromeOS uses this quirk. If native
memory buffer is enabled, GL_COMMANDS_COMPLETED_CHROMIUM is used for
correctness.

If you think this quirk is not needed anymore, I'll remove it in another
(prerequisite) CL.

+#endif
     gl->BeginQueryEXT(GL_COMMANDS_COMPLETED_CHROMIUM,
                       source_resource->gl_read_lock_query_id);
-#endif
   }
   DCHECK(!dest_resource->image_id);
   dest_resource->allocated = true;
@@ -1885,10 +1880,12 @@ void ResourceProvider::CopyResource(ResourceId source_id,
     // End query and create a read lock fence that will prevent access to
 // source resource until CopySubTextureCHROMIUM command has completed.
 #if defined(OS_CHROMEOS)
-    gl->EndQueryEXT(GL_COMMANDS_ISSUED_CHROMIUM);
-#else
-    gl->EndQueryEXT(GL_COMMANDS_COMPLETED_CHROMIUM);
+    if (source_resource->gpu_memory_buffer->GetHandle().type ==
+        gfx::SHARED_MEMORY_BUFFER)
+      gl->EndQueryEXT(GL_COMMANDS_ISSUED_CHROMIUM);
+    else
 #endif
+      gl->EndQueryEXT(GL_COMMANDS_COMPLETED_CHROMIUM);
     source_resource->read_lock_fence = make_scoped_refptr(
         new CopyTextureFence(gl, source_resource->gl_read_lock_query_id));
   } else {