Defer IPC messages to the GpuCommandBufferStub until GpuScheduler is rescheduled.

This stops the renderer process from continusously sending synchronous flushes during the swapbuffers period on mac.

TEST=WebGL on windows and mac, trybots
BUG=none
Review URL: http://codereview.chromium.org/6929045

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@84679 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 22 insertions, 1 deletions

diff --git a/gpu/command_buffer/service/gpu_scheduler.cc b/gpu/command_buffer/service/gpu_scheduler.cc
index 09a24fd..67ff504 100644
--- a/gpu/command_buffer/service/gpu_scheduler.cc
+++ b/gpu/command_buffer/service/gpu_scheduler.cc
@@ -196,13 +196,25 @@ void GpuScheduler::SetScheduled(bool scheduled) {
     --unscheduled_count_;
     DCHECK_GE(unscheduled_count_, 0);
 
-    if (unscheduled_count_ == 0)
+    if (unscheduled_count_ == 0) {
+      if (scheduled_callback_.get())
+        scheduled_callback_->Run();
+
       ScheduleProcessCommands();
+    }
   } else {
     ++unscheduled_count_;
   }
 }
 
+bool GpuScheduler::IsScheduled() {
+  return unscheduled_count_ == 0;
+}
+
+void GpuScheduler::SetScheduledCallback(Callback0::Type* scheduled_callback) {
+  scheduled_callback_.reset(scheduled_callback);
+}
+
 Buffer GpuScheduler::GetSharedMemoryBuffer(int32 shm_id) {
   return command_buffer_->GetTransferBuffer(shm_id);
 }
diff --git a/gpu/command_buffer/service/gpu_scheduler.h b/gpu/command_buffer/service/gpu_scheduler.h
index ebb2368..5fc1a9d 100644
--- a/gpu/command_buffer/service/gpu_scheduler.h
+++ b/gpu/command_buffer/service/gpu_scheduler.h
@@ -69,6 +69,13 @@ class GpuScheduler : public CommandBufferEngine {
   // false must eventually be paired by a call with true.
   void SetScheduled(bool is_scheduled);
 
+  // Returns whether the scheduler is currently scheduled to process commands.
+  bool IsScheduled();
+
+  // Sets a callback that is invoked just before scheduler is rescheduled.
+  // Takes ownership of callback object.
+  void SetScheduledCallback(Callback0::Type* scheduled_callback);
+
   // Implementation of CommandBufferEngine.
   virtual Buffer GetSharedMemoryBuffer(int32 shm_id);
   virtual void set_token(int32 token);
@@ -161,6 +168,8 @@ class GpuScheduler : public CommandBufferEngine {
   // Greater than zero if this is waiting to be rescheduled before continuing.
   int unscheduled_count_;
 
+  scoped_ptr<Callback0::Type> scheduled_callback_;
+
 #if defined(OS_MACOSX)
   scoped_ptr<AcceleratedSurface> surface_;
   uint64 swap_buffers_count_;