SF: Add VsyncSchedule skeleton
Pull the Scheduler::VsyncSchedule struct and related code into its own
file, as it will be extended with more per-display state, e.g. reactor
registrations, resync state machine, etc.
Add <scheduler/Features.h> for feature flags. Move Scheduler into its
namespace.
Bug: 185535769
Test: libsurfaceflinger_unittest
Change-Id: I6e10893632c5abf40380df924791d1fcc27c3cc2
diff --git a/services/surfaceflinger/Scheduler/VsyncSchedule.cpp b/services/surfaceflinger/Scheduler/VsyncSchedule.cpp
new file mode 100644
index 0000000..77d1223
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/VsyncSchedule.cpp
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <scheduler/Fps.h>
+
+#include "VsyncSchedule.h"
+
+#include "Timer.h"
+#include "VSyncDispatchTimerQueue.h"
+#include "VSyncPredictor.h"
+#include "VSyncReactor.h"
+
+#include "../TracedOrdinal.h"
+
+namespace android::scheduler {
+
+class VsyncSchedule::PredictedVsyncTracer {
+ // Invoked from the thread of the VsyncDispatch owned by this VsyncSchedule.
+ constexpr auto makeVsyncCallback() {
+ return [this](nsecs_t, nsecs_t, nsecs_t) {
+ mParity = !mParity;
+ schedule();
+ };
+ }
+
+public:
+ explicit PredictedVsyncTracer(VsyncDispatch& dispatch)
+ : mRegistration(dispatch, makeVsyncCallback(), __func__) {
+ schedule();
+ }
+
+private:
+ void schedule() { mRegistration.schedule({0, 0, 0}); }
+
+ TracedOrdinal<bool> mParity = {"VSYNC-predicted", 0};
+ VSyncCallbackRegistration mRegistration;
+};
+
+VsyncSchedule::VsyncSchedule(FeatureFlags features)
+ : mTracker(createTracker()),
+ mDispatch(createDispatch(*mTracker)),
+ mController(createController(*mTracker, features)) {
+ if (features.test(Feature::kTracePredictedVsync)) {
+ mTracer = std::make_unique<PredictedVsyncTracer>(*mDispatch);
+ }
+}
+
+VsyncSchedule::VsyncSchedule(TrackerPtr tracker, DispatchPtr dispatch, ControllerPtr controller)
+ : mTracker(std::move(tracker)),
+ mDispatch(std::move(dispatch)),
+ mController(std::move(controller)) {}
+
+VsyncSchedule::VsyncSchedule(VsyncSchedule&&) = default;
+VsyncSchedule::~VsyncSchedule() = default;
+
+void VsyncSchedule::dump(std::string& out) const {
+ out.append("VsyncController:\n");
+ mController->dump(out);
+
+ out.append("VsyncDispatch:\n");
+ mDispatch->dump(out);
+}
+
+VsyncSchedule::TrackerPtr VsyncSchedule::createTracker() {
+ // TODO(b/144707443): Tune constants.
+ constexpr nsecs_t kInitialPeriod = (60_Hz).getPeriodNsecs();
+ constexpr size_t kHistorySize = 20;
+ constexpr size_t kMinSamplesForPrediction = 6;
+ constexpr uint32_t kDiscardOutlierPercent = 20;
+
+ return std::make_unique<VSyncPredictor>(kInitialPeriod, kHistorySize, kMinSamplesForPrediction,
+ kDiscardOutlierPercent);
+}
+
+VsyncSchedule::DispatchPtr VsyncSchedule::createDispatch(VsyncTracker& tracker) {
+ using namespace std::chrono_literals;
+
+ // TODO(b/144707443): Tune constants.
+ constexpr std::chrono::nanoseconds kGroupDispatchWithin = 500us;
+ constexpr std::chrono::nanoseconds kSnapToSameVsyncWithin = 3ms;
+
+ return std::make_unique<VSyncDispatchTimerQueue>(std::make_unique<Timer>(), tracker,
+ kGroupDispatchWithin.count(),
+ kSnapToSameVsyncWithin.count());
+}
+
+VsyncSchedule::ControllerPtr VsyncSchedule::createController(VsyncTracker& tracker,
+ FeatureFlags features) {
+ // TODO(b/144707443): Tune constants.
+ constexpr size_t kMaxPendingFences = 20;
+ const bool hasKernelIdleTimer = features.test(Feature::kKernelIdleTimer);
+
+ auto reactor = std::make_unique<VSyncReactor>(std::make_unique<SystemClock>(), tracker,
+ kMaxPendingFences, hasKernelIdleTimer);
+
+ reactor->setIgnorePresentFences(!features.test(Feature::kPresentFences));
+ return reactor;
+}
+
+} // namespace android::scheduler