Deliver IPC messages together with SwapCompositorFrame

content/renderer/render_widget.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.
 
 #include "content/renderer/render_widget.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/debug/trace_event_synthetic_delay.h"
@@ skipping 18 matching lines @@
 #include "content/common/input_messages.h"
 #include "content/common/swapped_out_messages.h"
 #include "content/common/view_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/context_menu_params.h"
 #include "content/renderer/cursor_utils.h"
 #include "content/renderer/external_popup_menu.h"
 #include "content/renderer/gpu/compositor_output_surface.h"
 #include "content/renderer/gpu/compositor_software_output_device.h"
 #include "content/renderer/gpu/delegated_compositor_output_surface.h"
+#include "content/renderer/gpu/frame_swap_message_queue.h"
 #include "content/renderer/gpu/mailbox_output_surface.h"
 #include "content/renderer/gpu/render_widget_compositor.h"
 #include "content/renderer/ime_event_guard.h"
 #include "content/renderer/input/input_handler_manager.h"
 #include "content/renderer/pepper/pepper_plugin_instance_impl.h"
 #include "content/renderer/render_frame_impl.h"
 #include "content/renderer/render_process.h"
 #include "content/renderer/render_thread_impl.h"
 #include "content/renderer/renderer_webkitplatformsupport_impl.h"
 #include "content/renderer/resizing_mode_selector.h"
@@ skipping 344 matching lines @@
 #if defined(OS_ANDROID)
       text_field_is_dirty_(false),
       outstanding_ime_acks_(0),
       body_background_color_(SK_ColorWHITE),
 #endif
 #if defined(OS_MACOSX)
       cached_has_main_frame_horizontal_scrollbar_(false),
       cached_has_main_frame_vertical_scrollbar_(false),
 #endif
       popup_origin_scale_for_emulation_(0.f),
+      frame_swap_message_queue_(new FrameSwapMessageQueue()),
       resizing_mode_selector_(new ResizingModeSelector()),
       context_menu_source_type_(ui::MENU_SOURCE_MOUSE) {
   if (!swapped_out)
     RenderProcess::current()->AddRefProcess();
   DCHECK(RenderThread::Get());
   is_threaded_compositing_enabled_ =
       CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kEnableThreadedCompositing);
 }
 
@@ skipping 400 matching lines @@
 
 bool RenderWidget::ForceCompositingModeEnabled() {
   return false;
 }
 
 scoped_ptr<cc::OutputSurface> RenderWidget::CreateOutputSurface(bool fallback) {
   // For widgets that are never visible, we don't start the compositor, so we
   // never get a request for a cc::OutputSurface.
   DCHECK(!never_visible_);
 
+
 #if defined(OS_ANDROID)
   if (SynchronousCompositorFactory* factory =
       SynchronousCompositorFactory::GetInstance()) {
     return factory->CreateOutputSurface(routing_id());
   }
 #endif
 
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   bool use_software = fallback;
   if (command_line.HasSwitch(switches::kDisableGpuCompositing))
     use_software = true;
 
   scoped_refptr<ContextProviderCommandBuffer> context_provider;
   if (!use_software) {
     context_provider = ContextProviderCommandBuffer::Create(
         CreateGraphicsContext3D(), "RenderCompositor");
     if (!context_provider.get()) {
       // Cause the compositor to wait and try again.
       return scoped_ptr<cc::OutputSurface>();
     }
   }
 
+
   uint32 output_surface_id = next_output_surface_id_++;
   if (command_line.HasSwitch(switches::kEnableDelegatedRenderer)) {
     DCHECK(is_threaded_compositing_enabled_);
     return scoped_ptr<cc::OutputSurface>(
         new DelegatedCompositorOutputSurface(
             routing_id(),
             output_surface_id,
-            context_provider));
+            context_provider,
+            frame_swap_message_queue_));
   }
   if (!context_provider.get()) {
     scoped_ptr<cc::SoftwareOutputDevice> software_device(
         new CompositorSoftwareOutputDevice());
 
     return scoped_ptr<cc::OutputSurface>(new CompositorOutputSurface(
         routing_id(),
         output_surface_id,
         NULL,
         software_device.Pass(),
+        frame_swap_message_queue_,
         true));
   }
 
   if (command_line.HasSwitch(cc::switches::kCompositeToMailbox)) {
     // Composite-to-mailbox is currently used for layout tests in order to cause
     // them to draw inside in the renderer to do the readback there. This should
     // no longer be the case when crbug.com/311404 is fixed.
     DCHECK(is_threaded_compositing_enabled_ ||
            RenderThreadImpl::current()->layout_test_mode());
     cc::ResourceFormat format = cc::RGBA_8888;
 #if defined(OS_ANDROID)
     if (base::android::SysUtils::IsLowEndDevice())
       format = cc::RGB_565;
 #endif
     return scoped_ptr<cc::OutputSurface>(
         new MailboxOutputSurface(
             routing_id(),
             output_surface_id,
             context_provider,
             scoped_ptr<cc::SoftwareOutputDevice>(),
+            frame_swap_message_queue_,
             format));
   }
   bool use_swap_compositor_frame_message = false;
   return scoped_ptr<cc::OutputSurface>(
       new CompositorOutputSurface(
           routing_id(),
           output_surface_id,
           context_provider,
           scoped_ptr<cc::SoftwareOutputDevice>(),
+          frame_swap_message_queue_,
           use_swap_compositor_frame_message));
 }
 
 void RenderWidget::OnSwapBuffersAborted() {
   TRACE_EVENT0("renderer", "RenderWidget::OnSwapBuffersAborted");
   // Schedule another frame so the compositor learns about it.
   scheduleComposite();
 }
 
 void RenderWidget::OnSwapBuffersPosted() {
@@ skipping 324 matching lines @@
 void RenderWidget::didBecomeReadyForAdditionalInput() {
   TRACE_EVENT0("renderer", "RenderWidget::didBecomeReadyForAdditionalInput");
   FlushPendingInputEventAck();
 }
 
 void RenderWidget::DidCommitCompositorFrame() {
   FOR_EACH_OBSERVER(RenderFrameImpl, swapped_out_frames_,
                     DidCommitCompositorFrame());
 }
 
+namespace {
+
+// TODO(mkosiba): move most of this to RenderWidgetCompositor, although

[mkosiba (inactive), 2014/05/13 19:15:26]

..although it might be best to have this as a separate .cc/.h file.

+class RWSwapPromise : public cc::SwapPromise {
+ public:
+  RWSwapPromise(scoped_refptr<IPC::SyncMessageFilter> message_sender,
+                scoped_refptr<FrameSwapMessageQueue> message_queue,
+                IPC::Message* msg)
+      : message_sender_(message_sender),
+        message_queue_(message_queue),
+        msg_(msg) {
+    DCHECK(message_sender_.get());
+    DCHECK(message_queue_.get());
+    DCHECK(msg);
+  }
+
+  virtual ~RWSwapPromise() {
+    // The promise should be either fulfilled or broken before it's deleted.
+    DCHECK(!msg_);
+  }
+
+  virtual void DidSwap(cc::CompositorFrameMetadata* metadata) OVERRIDE {
+    if (!message_queue_->TryQueueMessage(metadata->source_frame_number, msg_)) {

[mkosiba (inactive), 2014/05/14 10:08:08]

the interesting case is how to handle messages that are being scheduled on the
impl thread after DidSwap is called but before the actual message is sent.
We'd need to postpone sending those messages till after the OutputSurface had
sent the IPC.
I was thinking of something along the lines of having two queues in the
FrameMessageQueue. We'd add to this queue instead of making the call to Send in
line 1287 and drain it from RenderWidget::didCompleteSwapBuffers.

I was also thinking that waiting for didSwapBuffers instead of
didCompleteSwapBuffers would be better in this context. WDYT?

[mkosiba (inactive), 2014/05/15 17:11:49]

Simpler option: acquire lock on FrameSwapMessageQueue before calling Drain,
release lock after calling Send on the IPC. :)

+      message_sender_->Send(msg_);
+    }
+    msg_ = NULL;
+  }
+
+  virtual void DidNotSwap(DidNotSwapReason reason) OVERRIDE {
+    message_sender_->Send(msg_);
+    msg_ = NULL;
+  }
+
+ private:
+  scoped_refptr<IPC::SyncMessageFilter> message_sender_;
+  scoped_refptr<FrameSwapMessageQueue> message_queue_;
+  IPC::Message* msg_;
+};
+
+} //  namespace
+
+void RenderWidget::QueueMessage(IPC::Message* msg) {
+  if (!compositor_ || !compositor_->commitRequested()) {
+    Send(msg);
+  } else {
+    scoped_ptr<cc::SwapPromise> promise(
+        new RWSwapPromise(RenderThreadImpl::current()->sync_message_filter(),
+                          frame_swap_message_queue_,
+                          msg));
+    compositor_->QueueSwapPromise(promise.Pass());
+  }
+}
+
 void RenderWidget::didCommitAndDrawCompositorFrame() {
   TRACE_EVENT0("gpu", "RenderWidget::didCommitAndDrawCompositorFrame");
   // Accelerated FPS tick for performance tests. See
   // tab_capture_performancetest.cc.  NOTE: Tests may break if this event is
   // renamed or moved.
   UNSHIPPED_TRACE_EVENT_INSTANT0("test_fps", "TestFrameTickGPU",
                                  TRACE_EVENT_SCOPE_THREAD);
   // Notify subclasses that we initiated the paint operation.
   DidInitiatePaint();
 }
@@ skipping 862 matching lines @@
 
 void RenderWidget::RegisterSwappedOutChildFrame(RenderFrameImpl* frame) {
   swapped_out_frames_.AddObserver(frame);
 }
 
 void RenderWidget::UnregisterSwappedOutChildFrame(RenderFrameImpl* frame) {
   swapped_out_frames_.RemoveObserver(frame);
 }
 
 }  // namespace content