Rework FlushSync to return early if commands have been processed since the last update

content/common/gpu/gpu_command_buffer_stub.cc

Index: content/common/gpu/gpu_command_buffer_stub.cc
diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index 8fc0855090404157a7e7e565edde23370d9f5ccd..431f90d30bc8ed9fac4fa4c9e36e50ec0425ea47 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -56,7 +56,8 @@ GpuCommandBufferStub::GpuCommandBufferStub(
 #endif  // defined(OS_WIN)
       renderer_id_(renderer_id),
       render_view_id_(render_view_id),
-      watchdog_(watchdog) {
+      watchdog_(watchdog),
+      task_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {
 }
 
 #if defined(OS_WIN)
@@ -256,7 +257,7 @@ void GpuCommandBufferStub::OnInitialize(
         parent_texture_id_)) {
       command_buffer_->SetPutOffsetChangeCallback(
           NewCallback(scheduler_.get(),
-                      &gpu::GpuScheduler::ProcessCommands));
+                      &gpu::GpuScheduler::PutChanged));
       scheduler_->SetSwapBuffersCallback(
           NewCallback(this, &GpuCommandBufferStub::OnSwapBuffers));
       scheduler_->SetLatchCallback(base::Bind(
@@ -301,13 +302,16 @@ void GpuCommandBufferStub::OnGetState(gpu::CommandBuffer::State* state) {
 
 void GpuCommandBufferStub::OnAsyncGetState() {
   gpu::CommandBuffer::State state = command_buffer_->GetState();
-  Send(new GpuCommandBufferMsg_UpdateState(route_id_, state));
+  IPC::Message* msg = new GpuCommandBufferMsg_UpdateState(route_id_, state);
+  msg->set_unblock(true);
+  Send(msg);
 }
 
 void GpuCommandBufferStub::OnFlush(int32 put_offset,
+                                   int32 last_known_get,
                                    gpu::CommandBuffer::State* state) {
   GPU_TRACE_EVENT0("gpu", "GpuCommandBufferStub::OnFlush");
-  *state = command_buffer_->FlushSync(put_offset);
+  *state = command_buffer_->FlushSync(put_offset, last_known_get);
   if (state->error == gpu::error::kLostContext &&
       gfx::GLContext::LosesAllContextsOnContextLost())
     channel_->LoseAllContexts();
@@ -315,12 +319,11 @@ void GpuCommandBufferStub::OnFlush(int32 put_offset,
 
 void GpuCommandBufferStub::OnAsyncFlush(int32 put_offset) {
   GPU_TRACE_EVENT0("gpu", "GpuCommandBufferStub::OnAsyncFlush");
-  gpu::CommandBuffer::State state = command_buffer_->FlushSync(put_offset);
-  if (state.error == gpu::error::kLostContext &&
-      gfx::GLContext::LosesAllContextsOnContextLost())
-    channel_->LoseAllContexts();

[apatrick_chromium, 2011/04/27 22:52:44]

Why did you remove this?

[piman, 2011/04/27 23:44:29]

Since we're not waiting on any command to execute, it doesn't really make sense
anymore here.
I meant to put it back into OnAsyncGetState, but missed it. It's there now
(renamed "ReportState"). I also added it to OnGetState, it makes sense there
too.

-  else
-    Send(new GpuCommandBufferMsg_UpdateState(route_id_, state));
+  command_buffer_->Flush(put_offset);
+  // TODO(piman): Do this everytime the scheduler finishes processing a batch of
+  // commands.
+  MessageLoop::current()->PostTask(FROM_HERE,
+      task_factory_.NewRunnableMethod(&GpuCommandBufferStub::OnAsyncGetState));
 }
 
 void GpuCommandBufferStub::OnCreateTransferBuffer(int32 size,