Separate impl and main latency recovery settings

Currently, there is a single settings flag controlling CC latency
recovery both on main thread and impl thread. This CL breaks that into
two separate flags that can be controlled independently.

Bug: 993895
Change-Id: I2caae6f5f2cd25332d8a164e082b313152e5e0b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1869749Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Reviewed-by: Stefan Zager <szager@chromium.org>
Auto-Submit: Mohsen Izadi <mohsen@chromium.org>
Commit-Queue: Stefan Zager <szager@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737561}

cc/scheduler/scheduler.cc

@@ -932,7 +932,7 @@ bool Scheduler::ShouldRecoverMainLatency(
     bool can_activate_before_deadline) const {
   DCHECK(!settings_.using_synchronous_renderer_compositor);
 
-  if (!settings_.enable_latency_recovery)
+  if (!settings_.enable_main_latency_recovery)
     return false;
 
   // The main thread is in a low latency mode and there's no need to recover.
@@ -964,7 +964,7 @@ bool Scheduler::ShouldRecoverImplLatency(
     bool can_activate_before_deadline) const {
   DCHECK(!settings_.using_synchronous_renderer_compositor);
 
-  if (!settings_.enable_latency_recovery)
+  if (!settings_.enable_impl_latency_recovery)
     return false;
 
   // Disable impl thread latency recovery when using the unthrottled

cc/scheduler/scheduler_settings.cc

@@ -25,7 +25,10 @@ SchedulerSettings::AsValue() const {
                     maximum_number_of_failed_draws_before_draw_is_forced);
   state->SetBoolean("using_synchronous_renderer_compositor",
                     using_synchronous_renderer_compositor);
-  state->SetBoolean("enable_latency_recovery", enable_latency_recovery);
+  state->SetBoolean("enable_impl_latency_recovery",
+                    enable_impl_latency_recovery);
+  state->SetBoolean("enable_main_latency_recovery",
+                    enable_main_latency_recovery);
   state->SetBoolean("wait_for_all_pipeline_stages_before_draw",
                     wait_for_all_pipeline_stages_before_draw);
   return std::move(state);

cc/scheduler/scheduler_settings.h

@@ -39,13 +39,14 @@ class CC_EXPORT SchedulerSettings {
   // This is enabled for android-webview.
   bool using_synchronous_renderer_compositor = false;
 
-  // This is used to determine whether some begin-frames should be skipped (both
-  // in the main-thread and the compositor-thread) if previous frames have had
-  // high latency.
+  // This is used to determine whether some begin-frames should be skipped
+  // (either in the main-thread or the compositor-thread) if previous frames
+  // have had high latency.
   // It is enabled by default on desktop platforms, and has been recently
   // disabled by default on android. It may be disabled on all platforms. See
   // more in https://crbug.com/933846
-  bool enable_latency_recovery = true;
+  bool enable_impl_latency_recovery = true;
+  bool enable_main_latency_recovery = true;
 
   // Turning this on effectively disables pipelining of compositor frame
   // production stages by waiting for each stage to complete before producing

cc/test/layer_tree_test.cc

@@ -1048,7 +1048,8 @@ void LayerTreeTest::RunTest(CompositorMode mode) {
   }
   // Disable latency recovery to make the scheduler more predictable in its
   // actions and less dependent on timings to make decisions.
-  settings_.enable_latency_recovery = false;
+  settings_.enable_impl_latency_recovery = false;
+  settings_.enable_main_latency_recovery = false;
   InitializeSettings(&settings_);
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(

cc/trees/layer_tree_settings.cc

@@ -26,7 +26,10 @@ SchedulerSettings LayerTreeSettings::ToSchedulerSettings() const {
       main_frame_before_activation_enabled;
   scheduler_settings.using_synchronous_renderer_compositor =
       using_synchronous_renderer_compositor;
-  scheduler_settings.enable_latency_recovery = enable_latency_recovery;
+  scheduler_settings.enable_impl_latency_recovery =
+      enable_impl_latency_recovery;
+  scheduler_settings.enable_main_latency_recovery =
+      enable_main_latency_recovery;
   scheduler_settings.wait_for_all_pipeline_stages_before_draw =
       wait_for_all_pipeline_stages_before_draw;
   return scheduler_settings;

cc/trees/layer_tree_settings.h

@@ -40,7 +40,8 @@ class CC_EXPORT LayerTreeSettings {
   // When |enable_early_damage_check| is true, the early damage check is
   // performed if one of the last |damaged_frame_limit| frames had no damage.
   int damaged_frame_limit = 3;
-  bool enable_latency_recovery = true;
+  bool enable_impl_latency_recovery = true;
+  bool enable_main_latency_recovery = true;
   bool can_use_lcd_text = true;
   bool gpu_rasterization_forced = false;
   bool gpu_rasterization_disabled = false;

content/browser/renderer_host/compositor_impl_android.cc

@@ -397,7 +397,8 @@ void CompositorImpl::CreateLayerTreeHost() {
   settings.use_painted_device_scale_factor = true;
   // TODO(crbug.com/933846): LatencyRecovery is causing jank on Android. Disable
   // for now, with a plan to disable more widely once viz launches.
-  settings.enable_latency_recovery = false;
+  settings.enable_impl_latency_recovery = false;
+  settings.enable_main_latency_recovery = false;
 
   animation_host_ = cc::AnimationHost::CreateMainInstance();
 

content/renderer/render_widget.cc

@@ -3135,12 +3135,14 @@ cc::LayerTreeSettings RenderWidget::GenerateLayerTreeSettings(
 
   if (cmd.HasSwitch(switches::kRunAllCompositorStagesBeforeDraw)) {
     settings.wait_for_all_pipeline_stages_before_draw = true;
-    settings.enable_latency_recovery = false;
+    settings.enable_impl_latency_recovery = false;
+    settings.enable_main_latency_recovery = false;
   }
 #if defined(OS_ANDROID)
   // TODO(crbug.com/933846): LatencyRecovery is causing jank on Android. Disable
   // in viz mode for now, with plan to disable more widely once viz launches.
-  settings.enable_latency_recovery = false;
+  settings.enable_impl_latency_recovery = false;
+  settings.enable_main_latency_recovery = false;
 #endif
 
   settings.enable_image_animation_resync =

ui/compositor/compositor.cc

@@ -195,7 +195,8 @@ Compositor::Compositor(const viz::FrameSinkId& frame_sink_id,
 
   if (command_line->HasSwitch(switches::kRunAllCompositorStagesBeforeDraw)) {
     settings.wait_for_all_pipeline_stages_before_draw = true;
-    settings.enable_latency_recovery = false;
+    settings.enable_impl_latency_recovery = false;
+    settings.enable_main_latency_recovery = false;
   }
 
   if (base::FeatureList::IsEnabled(