remove vsync_recorder

Author: farchond

shell/platform/fuchsia/flutter/BUILD.gn

@@ -83,8 +83,6 @@ template("runner_sources") {
       "thread.cc",
       "thread.h",
       "unique_fdio_ns.h",
-      "vsync_recorder.cc",
-      "vsync_recorder.h",
       "vsync_waiter.cc",
       "vsync_waiter.h",
       "vulkan_surface.cc",
@@ -455,7 +453,6 @@ executable("flutter_runner_unittests") {
     "runner_unittest.cc",
     "tests/engine_unittests.cc",
     "tests/flutter_runner_product_configuration_unittests.cc",
-    "tests/vsync_recorder_unittests.cc",
   ]
 
   # This is needed for //third_party/googletest for linking zircon symbols.

shell/platform/fuchsia/flutter/default_session_connection.cc

@@ -7,7 +7,6 @@
 #include "flutter/fml/make_copyable.h"
 #include "flutter/fml/trace_event.h"
 
-#include "vsync_recorder.h"
 #include "vsync_waiter.h"
 
 namespace flutter_runner {
@@ -200,8 +199,8 @@ DefaultSessionConnection::DefaultSessionConnection(
                        num_presents_handled);
         FML_DCHECK(frames_in_flight_ >= 0);
 
-        VsyncRecorder::GetInstance().UpdateFramePresentedInfo(
-            zx::time(info.actual_presentation_time));
+        last_presentation_time_ = fml::TimePoint::FromEpochDelta(
+            fml::TimeDelta::FromNanoseconds(info.actual_presentation_time));
 
         // Call the client-provided callback once we are done using |info|.
         on_frame_presented_callback_(std::move(info));
@@ -230,8 +229,7 @@ DefaultSessionConnection::DefaultSessionConnection(
         // If Scenic alloted us 0 frames to begin with, we should fail here.
         FML_CHECK(frames_in_flight_allowed_ > 0);
 
-        VsyncRecorder::GetInstance().UpdateNextPresentationInfo(
-            std::move(info));
+        UpdateNextPresentationInfo(std::move(info));
 
         initialized_ = true;
 
@@ -314,7 +312,7 @@ void DefaultSessionConnection::PresentSession() {
   // tasks.
 
   fml::TimeDelta presentation_interval =
-      VsyncRecorder::GetInstance().GetCurrentVsyncInfo().presentation_interval;
+      GetCurrentVsyncInfo().presentation_interval;
 
   fml::TimePoint next_latch_point = CalculateNextLatchPoint(
       fml::TimePoint::Now(), present_requested_time_,
@@ -344,8 +342,7 @@ void DefaultSessionConnection::PresentSession() {
         }
 
         frames_in_flight_allowed_ = info.remaining_presents_in_flight_allowed;
-        VsyncRecorder::GetInstance().UpdateNextPresentationInfo(
-            std::move(info));
+        UpdateNextPresentationInfo(std::move(info));
       });
 }
 
@@ -373,13 +370,11 @@ void DefaultSessionConnection::FireCallbackMaybe() {
 FlutterFrameTimes DefaultSessionConnection::GetTargetTimesHelper(
     bool secondary_callback) {
   fml::TimeDelta presentation_interval =
-      VsyncRecorder::GetInstance().GetCurrentVsyncInfo().presentation_interval;
+      GetCurrentVsyncInfo().presentation_interval;
 
-  fml::TimePoint next_vsync =
-      VsyncRecorder::GetInstance().GetCurrentVsyncInfo().presentation_time;
+  fml::TimePoint next_vsync = GetCurrentVsyncInfo().presentation_time;
   fml::TimePoint now = fml::TimePoint::Now();
-  fml::TimePoint last_presentation_time =
-      VsyncRecorder::GetInstance().GetLastPresentationTime();
+  fml::TimePoint last_presentation_time = last_presentation_time_;
   if (next_vsync <= now) {
     next_vsync =
         SnapToNextPhase(now, last_presentation_time, presentation_interval);
@@ -391,4 +386,24 @@ FlutterFrameTimes DefaultSessionConnection::GetTargetTimesHelper(
                         last_targetted_vsync, now, next_vsync);
 }
 
+void DefaultSessionConnection::UpdateNextPresentationInfo(
+    fuchsia::scenic::scheduling::FuturePresentationTimes info) {
+  auto next_time = next_presentation_info_.presentation_time();
+  // Get the earliest vsync time that is after our recorded |presentation_time|.
+  for (auto& presentation_info : info.future_presentations) {
+    auto current_time = presentation_info.presentation_time();
+
+    if (current_time > next_time) {
+      next_presentation_info_.set_presentation_time(current_time);
+      return;
+    }
+  }
+}
+
+VsyncInfo DefaultSessionConnection::GetCurrentVsyncInfo() const {
+  return {fml::TimePoint::FromEpochDelta(fml::TimeDelta::FromNanoseconds(
+              next_presentation_info_.presentation_time())),
+          kDefaultPresentationInterval};
+}
+
 }  // namespace flutter_runner

shell/platform/fuchsia/flutter/default_session_connection.h

@@ -28,6 +28,16 @@ struct FlutterFrameTimes {
   fml::TimePoint frame_target;
 };
 
+struct VsyncInfo {
+  fml::TimePoint presentation_time;
+  fml::TimeDelta presentation_interval;
+};
+
+// Assume a 60hz refresh rate before we have enough past
+// |fuchsia::scenic::scheduling::PresentationInfo|s to calculate it ourselves.
+static constexpr fml::TimeDelta kDefaultPresentationInterval =
+    fml::TimeDelta::FromSecondsF(1.0 / 60.0);
+
 // The component residing on the raster thread that is responsible for
 // maintaining the Scenic session connection and presenting node updates.
 class DefaultSessionConnection final : public flutter::SessionWrapper {
@@ -111,8 +121,11 @@ class DefaultSessionConnection final : public flutter::SessionWrapper {
   int frames_in_flight_allowed_ = 0;
   bool present_session_pending_ = false;
 
-  ////// Flutter Animator logic.
+  // Flutter framework pipeline logic.
 
+  // The following fields can be accessed from both the raster and UI threads,
+  // so guard them with this mutex. If performance dictates, this could probably
+  // be made lock-free, but it's much easier to reason about with this mutex.
   std::mutex mutex_;
 
   // This is the last Vsync we submitted as the frame_target_time to
@@ -124,8 +137,26 @@ class DefaultSessionConnection final : public flutter::SessionWrapper {
   // This is true iff AwaitVSync() was called but we could not schedule a frame.
   bool fire_callback_request_pending_ = false;
 
+  // The callback passed in from VsyncWaiter which eventually runs on the UI
+  // thread.
   FireCallbackCallback fire_callback_;
 
+  // VsyncRecorder logic.
+
+  // Update the next Vsync info to |next_presentation_info_|. This is expected
+  // to be called in |scenic::Session::Present2| immedaite callbacks with the
+  // presentation info provided by Scenic.  Only the next vsync
+  // information will be saved (in order to handle edge cases involving
+  // multiple Scenic sessions in the same process). This function is safe to
+  // call from any thread.
+  void UpdateNextPresentationInfo(
+      fuchsia::scenic::scheduling::FuturePresentationTimes info);
+
+  VsyncInfo GetCurrentVsyncInfo() const;
+
+  fuchsia::scenic::scheduling::PresentationInfo next_presentation_info_;
+  fml::TimePoint last_presentation_time_ = fml::TimePoint::Now();
+
   FML_DISALLOW_COPY_AND_ASSIGN(DefaultSessionConnection);
 };
 

shell/platform/fuchsia/flutter/vsync_recorder.cc

@@ -15,7 +15,6 @@
 #include "flutter/fml/trace_event.h"
 
 #include "flutter_runner_product_configuration.h"
-#include "vsync_recorder.h"
 
 namespace flutter_runner {