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diff --git a/services/surfaceflinger/Scheduler/PhaseOffsets.h b/services/surfaceflinger/Scheduler/PhaseOffsets.h
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+/*
+ * Copyright 2019 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.
+ */
+
+#pragma once
+
+#include <unordered_map>
+
+#include "RefreshRateConfigs.h"
+#include "VSyncModulator.h"
+
+namespace android::scheduler {
+
+/*
+ * This class encapsulates offsets for different refresh rates. Depending
+ * on what refresh rate we are using, and wheter we are composing in GL,
+ * different offsets will help us with latency. This class keeps track of
+ * which mode the device is on, and returns approprate offsets when needed.
+ */
+class PhaseConfiguration {
+public:
+    using Offsets = VSyncModulator::OffsetsConfig;
+
+    virtual ~PhaseConfiguration();
+
+    virtual Offsets getCurrentOffsets() const = 0;
+    virtual Offsets getOffsetsForRefreshRate(float fps) const = 0;
+
+    virtual void setRefreshRateFps(float fps) = 0;
+
+    virtual void dump(std::string& result) const = 0;
+};
+
+namespace impl {
+
+/*
+ * This is the old implementation of phase offsets and considered as deprecated.
+ * PhaseDurations is the new implementation.
+ */
+class PhaseOffsets : public scheduler::PhaseConfiguration {
+public:
+    PhaseOffsets(const scheduler::RefreshRateConfigs&);
+
+    // Returns early, early GL, and late offsets for Apps and SF for a given refresh rate.
+    Offsets getOffsetsForRefreshRate(float fps) const override;
+
+    // Returns early, early GL, and late offsets for Apps and SF.
+    Offsets getCurrentOffsets() const override { return getOffsetsForRefreshRate(mRefreshRateFps); }
+
+    // This function should be called when the device is switching between different
+    // refresh rates, to properly update the offsets.
+    void setRefreshRateFps(float fps) override { mRefreshRateFps = fps; }
+
+    // Returns current offsets in human friendly format.
+    void dump(std::string& result) const override;
+
+protected:
+    // Used for unit tests
+    PhaseOffsets(const std::vector<float>& refreshRates, float currentFps,
+                 nsecs_t vsyncPhaseOffsetNs, nsecs_t sfVSyncPhaseOffsetNs,
+                 std::optional<nsecs_t> earlySfOffsetNs, std::optional<nsecs_t> earlyGlSfOffsetNs,
+                 std::optional<nsecs_t> earlyAppOffsetNs, std::optional<nsecs_t> earlyGlAppOffsetNs,
+                 nsecs_t thresholdForNextVsync);
+    std::unordered_map<float, Offsets> initializeOffsets(
+            const std::vector<float>& refreshRates) const;
+    Offsets getDefaultOffsets(nsecs_t vsyncPeriod) const;
+    Offsets getHighFpsOffsets(nsecs_t vsyncPeriod) const;
+    Offsets getPhaseOffsets(float fps, nsecs_t vsyncPeriod) const;
+
+    const nsecs_t mVSyncPhaseOffsetNs;
+    const nsecs_t mSfVSyncPhaseOffsetNs;
+    const std::optional<nsecs_t> mEarlySfOffsetNs;
+    const std::optional<nsecs_t> mEarlyGlSfOffsetNs;
+    const std::optional<nsecs_t> mEarlyAppOffsetNs;
+    const std::optional<nsecs_t> mEarlyGlAppOffsetNs;
+    const nsecs_t mThresholdForNextVsync;
+    const std::unordered_map<float, Offsets> mOffsets;
+
+    std::atomic<float> mRefreshRateFps;
+};
+
+/*
+ * Class that encapsulates the phase offsets for SurfaceFlinger and App.
+ * The offsets are calculated from durations for each one of the (late, early, earlyGL)
+ * offset types.
+ */
+class PhaseDurations : public scheduler::PhaseConfiguration {
+public:
+    PhaseDurations(const scheduler::RefreshRateConfigs&);
+
+    // Returns early, early GL, and late offsets for Apps and SF for a given refresh rate.
+    Offsets getOffsetsForRefreshRate(float fps) const override;
+
+    // Returns early, early GL, and late offsets for Apps and SF.
+    Offsets getCurrentOffsets() const override { return getOffsetsForRefreshRate(mRefreshRateFps); }
+
+    // This function should be called when the device is switching between different
+    // refresh rates, to properly update the offsets.
+    void setRefreshRateFps(float fps) override { mRefreshRateFps = fps; }
+
+    // Returns current offsets in human friendly format.
+    void dump(std::string& result) const override;
+
+protected:
+    // Used for unit tests
+    PhaseDurations(const std::vector<float>& refreshRates, float currentFps, nsecs_t sfDuration,
+                   nsecs_t appDuration, nsecs_t sfEarlyDuration, nsecs_t appEarlyDuration,
+                   nsecs_t sfEarlyGlDuration, nsecs_t appEarlyGlDuration);
+
+private:
+    std::unordered_map<float, Offsets> initializeOffsets(const std::vector<float>&) const;
+    PhaseDurations::Offsets constructOffsets(nsecs_t vsyncDuration) const;
+
+    const nsecs_t mSfDuration;
+    const nsecs_t mAppDuration;
+
+    const nsecs_t mSfEarlyDuration;
+    const nsecs_t mAppEarlyDuration;
+
+    const nsecs_t mSfEarlyGlDuration;
+    const nsecs_t mAppEarlyGlDuration;
+
+    const std::unordered_map<float, Offsets> mOffsets;
+
+    std::atomic<float> mRefreshRateFps;
+};
+
+} // namespace impl
+} // namespace android::scheduler