(not for commit) Simplified multi-threaded Ganesh with lock on Flush only.

gpu/command_buffer/client/gles2_implementation.cc

 // Copyright (c) 2012 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.
 
 // A class to emulate GLES2 over command buffers.
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 
 #include <GLES2/gl2ext.h>
 #include <GLES2/gl2extchromium.h>
@@ skipping 815 matching lines @@
 
 void GLES2Implementation::ShallowFlushCHROMIUM() {
   GPU_CLIENT_SINGLE_THREAD_CHECK();
   GPU_CLIENT_LOG("[" << GetLogPrefix() << "] glShallowFlushCHROMIUM()");
   // Flush our command buffer
   // (tell the service to execute up to the flush cmd.)
   helper_->CommandBufferHelper::Flush();
   // TODO(piman): Add the FreeEverything() logic here.
 }
 
+void GLES2Implementation::SetSafeFlushPoint() {
+  GPU_CLIENT_LOG("[" << GetLogPrefix() << "] glSetSafeFlushPoint()");
+  // Save the current command offset for SafeFlush().
+  helper_->CommandBufferHelper::SetSafeFlushPoint();
+}
+
+void GLES2Implementation::SafeFlush() {
+  GPU_CLIENT_LOG("[" << GetLogPrefix() << "] glSafeFlushCHROMIUM()");
+  // Flush our command buffer up to the last safe flush point.
+  // (tell the service to execute up to the flush cmd.)
+  helper_->CommandBufferHelper::SafeFlush();
+}
+
 void GLES2Implementation::Finish() {
   GPU_CLIENT_SINGLE_THREAD_CHECK();
   FinishHelper();
 }
 
 void GLES2Implementation::ShallowFinishCHROMIUM() {
   GPU_CLIENT_SINGLE_THREAD_CHECK();
   TRACE_EVENT0("gpu", "GLES2::ShallowFinishCHROMIUM");
   // Flush our command buffer (tell the service to execute up to the flush cmd
   // and don't return until it completes).
@@ skipping 3527 matching lines @@
   return false;
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/client/gles2_implementation_impl_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu