SF: Move ownership of VsyncModulator to Scheduler

...as a prerequisite for calculating the VSYNC deadline of the leader
display (and deriving per-display state from it, e.g. present fences,
traces) in the Scheduler.

Bug: 241285475
Bug: 241285191
Test: Boot
Change-Id: Ieea136616435464dd0756525f94441b8e82ad06a
diff --git a/services/surfaceflinger/RegionSamplingThread.h b/services/surfaceflinger/RegionSamplingThread.h
index b62b15c..e8c891e 100644
--- a/services/surfaceflinger/RegionSamplingThread.h
+++ b/services/surfaceflinger/RegionSamplingThread.h
@@ -37,7 +37,6 @@
 namespace android {
 
 class Layer;
-class Scheduler;
 class SurfaceFlinger;
 struct SamplingOffsetCallback;
 
diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index bc465ce..1fc1519 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -60,8 +60,12 @@
 
 namespace android::scheduler {
 
-Scheduler::Scheduler(ICompositor& compositor, ISchedulerCallback& callback, FeatureFlags features)
-      : impl::MessageQueue(compositor), mFeatures(features), mSchedulerCallback(callback) {}
+Scheduler::Scheduler(ICompositor& compositor, ISchedulerCallback& callback, FeatureFlags features,
+                     sp<VsyncModulator> modulatorPtr)
+      : impl::MessageQueue(compositor),
+        mFeatures(features),
+        mVsyncModulator(std::move(modulatorPtr)),
+        mSchedulerCallback(callback) {}
 
 Scheduler::~Scheduler() {
     // MessageQueue depends on VsyncSchedule, so first destroy it.
@@ -186,17 +190,19 @@
     };
 }
 
-ConnectionHandle Scheduler::createConnection(const char* connectionName,
-                                             frametimeline::TokenManager* tokenManager,
-                                             std::chrono::nanoseconds workDuration,
-                                             std::chrono::nanoseconds readyDuration) {
-    auto throttleVsync = makeThrottleVsyncCallback();
-    auto getVsyncPeriod = makeGetVsyncPeriodFunction();
-    auto eventThread =
-            std::make_unique<impl::EventThread>(connectionName, *mVsyncSchedule, tokenManager,
-                                                std::move(throttleVsync), std::move(getVsyncPeriod),
-                                                workDuration, readyDuration);
-    return createConnection(std::move(eventThread));
+ConnectionHandle Scheduler::createEventThread(Cycle cycle,
+                                              frametimeline::TokenManager* tokenManager,
+                                              std::chrono::nanoseconds workDuration,
+                                              std::chrono::nanoseconds readyDuration) {
+    auto eventThread = std::make_unique<impl::EventThread>(cycle == Cycle::Render ? "app" : "appSf",
+                                                           *mVsyncSchedule, tokenManager,
+                                                           makeThrottleVsyncCallback(),
+                                                           makeGetVsyncPeriodFunction(),
+                                                           workDuration, readyDuration);
+
+    auto& handle = cycle == Cycle::Render ? mAppConnectionHandle : mSfConnectionHandle;
+    handle = createConnection(std::move(eventThread));
+    return handle;
 }
 
 ConnectionHandle Scheduler::createConnection(std::unique_ptr<EventThread> eventThread) {
@@ -356,6 +362,20 @@
     thread->setDuration(workDuration, readyDuration);
 }
 
+void Scheduler::setVsyncConfigSet(const VsyncConfigSet& configs, Period vsyncPeriod) {
+    setVsyncConfig(mVsyncModulator->setVsyncConfigSet(configs), vsyncPeriod);
+}
+
+void Scheduler::setVsyncConfig(const VsyncConfig& config, Period vsyncPeriod) {
+    setDuration(mAppConnectionHandle,
+                /* workDuration */ config.appWorkDuration,
+                /* readyDuration */ config.sfWorkDuration);
+    setDuration(mSfConnectionHandle,
+                /* workDuration */ vsyncPeriod,
+                /* readyDuration */ config.sfWorkDuration);
+    setDuration(config.sfWorkDuration);
+}
+
 void Scheduler::enableHardwareVsync() {
     std::lock_guard<std::mutex> lock(mHWVsyncLock);
     if (!mPrimaryHWVsyncEnabled && mHWVsyncAvailable) {
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index a3e28b6..ef7d0cf 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -36,6 +36,7 @@
 #include <ftl/optional.h>
 #include <scheduler/Features.h>
 #include <scheduler/Time.h>
+#include <scheduler/VsyncConfig.h>
 #include <ui/DisplayId.h>
 
 #include "Display/DisplayMap.h"
@@ -47,6 +48,7 @@
 #include "OneShotTimer.h"
 #include "RefreshRateSelector.h"
 #include "Utils/Dumper.h"
+#include "VsyncModulator.h"
 #include "VsyncSchedule.h"
 
 namespace android::scheduler {
@@ -104,7 +106,7 @@
     using Impl = android::impl::MessageQueue;
 
 public:
-    Scheduler(ICompositor&, ISchedulerCallback&, FeatureFlags);
+    Scheduler(ICompositor&, ISchedulerCallback&, FeatureFlags, sp<VsyncModulator>);
     virtual ~Scheduler();
 
     void startTimers();
@@ -146,9 +148,14 @@
         return std::move(future);
     }
 
-    ConnectionHandle createConnection(const char* connectionName, frametimeline::TokenManager*,
-                                      std::chrono::nanoseconds workDuration,
-                                      std::chrono::nanoseconds readyDuration);
+    enum class Cycle {
+        Render,       // Surface rendering.
+        LastComposite // Ahead of display compositing by one refresh period.
+    };
+
+    ConnectionHandle createEventThread(Cycle, frametimeline::TokenManager*,
+                                       std::chrono::nanoseconds workDuration,
+                                       std::chrono::nanoseconds readyDuration);
 
     sp<IDisplayEventConnection> createDisplayEventConnection(
             ConnectionHandle, EventRegistrationFlags eventRegistration = {});
@@ -168,6 +175,18 @@
     void setDuration(ConnectionHandle, std::chrono::nanoseconds workDuration,
                      std::chrono::nanoseconds readyDuration);
 
+    const VsyncModulator& vsyncModulator() const { return *mVsyncModulator; }
+
+    template <typename... Args,
+              typename Handler = std::optional<VsyncConfig> (VsyncModulator::*)(Args...)>
+    void modulateVsync(Handler handler, Args... args) {
+        if (const auto config = (*mVsyncModulator.*handler)(args...)) {
+            setVsyncConfig(*config, getLeaderVsyncPeriod());
+        }
+    }
+
+    void setVsyncConfigSet(const VsyncConfigSet&, Period vsyncPeriod);
+
     // Sets the render rate for the scheduler to run at.
     void setRenderRate(Fps);
 
@@ -270,6 +289,7 @@
     void displayPowerTimerCallback(TimerState);
 
     void setVsyncPeriod(nsecs_t period);
+    void setVsyncConfig(const VsyncConfig&, Period vsyncPeriod);
 
     // Chooses a leader among the registered displays, unless `leaderIdOpt` is specified. The new
     // `mLeaderDisplayId` is never `std::nullopt`.
@@ -330,6 +350,9 @@
     mutable std::mutex mConnectionsLock;
     std::unordered_map<ConnectionHandle, Connection> mConnections GUARDED_BY(mConnectionsLock);
 
+    ConnectionHandle mAppConnectionHandle;
+    ConnectionHandle mSfConnectionHandle;
+
     mutable std::mutex mHWVsyncLock;
     bool mPrimaryHWVsyncEnabled GUARDED_BY(mHWVsyncLock) = false;
     bool mHWVsyncAvailable GUARDED_BY(mHWVsyncLock) = false;
@@ -339,6 +362,9 @@
     const FeatureFlags mFeatures;
     std::optional<VsyncSchedule> mVsyncSchedule;
 
+    // Shifts the VSYNC phase during certain transactions and refresh rate changes.
+    const sp<VsyncModulator> mVsyncModulator;
+
     // Used to choose refresh rate if content detection is enabled.
     LayerHistory mLayerHistory;
 
diff --git a/services/surfaceflinger/Scheduler/VsyncModulator.h b/services/surfaceflinger/Scheduler/VsyncModulator.h
index 4b01ec3..dc4dafd 100644
--- a/services/surfaceflinger/Scheduler/VsyncModulator.h
+++ b/services/surfaceflinger/Scheduler/VsyncModulator.h
@@ -25,21 +25,13 @@
 #include <binder/IBinder.h>
 #include <utils/Timers.h>
 
+#include <scheduler/TransactionSchedule.h>
 #include <scheduler/VsyncConfig.h>
 
 #include "../WpHash.h"
 
 namespace android::scheduler {
 
-// State machine controlled by transaction flags. VsyncModulator switches to early phase offsets
-// when a transaction is flagged EarlyStart or Early, lasting until an EarlyEnd transaction or a
-// fixed number of frames, respectively.
-enum class TransactionSchedule {
-    Late,  // Default.
-    EarlyStart,
-    EarlyEnd
-};
-
 // Modulates VSYNC phase depending on transaction schedule and refresh rate changes.
 class VsyncModulator : public IBinder::DeathRecipient {
 public:
diff --git a/services/surfaceflinger/Scheduler/include/scheduler/TransactionSchedule.h b/services/surfaceflinger/Scheduler/include/scheduler/TransactionSchedule.h
new file mode 100644
index 0000000..6fc44dd
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/include/scheduler/TransactionSchedule.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2023 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
+
+namespace android::scheduler {
+
+// State machine controlled by transaction flags. VsyncModulator switches to early phase offsets
+// when a transaction is flagged EarlyStart or Early, lasting until an EarlyEnd transaction or a
+// fixed number of frames, respectively.
+enum class TransactionSchedule {
+    Late, // Default.
+    EarlyStart,
+    EarlyEnd
+};
+
+} // namespace android::scheduler
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 6a056d3..be055b2 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -142,6 +142,7 @@
 #include "Scheduler/LayerHistory.h"
 #include "Scheduler/Scheduler.h"
 #include "Scheduler/VsyncConfiguration.h"
+#include "Scheduler/VsyncModulator.h"
 #include "ScreenCaptureOutput.h"
 #include "StartPropertySetThread.h"
 #include "SurfaceFlingerProperties.h"
@@ -189,6 +190,7 @@
 using gui::LayerMetadata;
 using gui::WindowInfo;
 using gui::aidl_utils::binderStatusFromStatusT;
+using scheduler::VsyncModulator;
 using ui::Dataspace;
 using ui::DisplayPrimaries;
 using ui::RenderIntent;
@@ -1163,7 +1165,7 @@
             mScheduler->resyncToHardwareVsync(true, mode.modePtr->getFps());
             // As we called to set period, we will call to onRefreshRateChangeCompleted once
             // VsyncController model is locked.
-            modulateVsync(&VsyncModulator::onRefreshRateChangeInitiated);
+            mScheduler->modulateVsync(&VsyncModulator::onRefreshRateChangeInitiated);
 
             updatePhaseConfiguration(mode.fps);
             mScheduler->setModeChangePending(true);
@@ -2039,7 +2041,7 @@
     bool periodFlushed = false;
     mScheduler->addResyncSample(timestamp, vsyncPeriod, &periodFlushed);
     if (periodFlushed) {
-        modulateVsync(&VsyncModulator::onRefreshRateChangeCompleted);
+        mScheduler->modulateVsync(&VsyncModulator::onRefreshRateChangeCompleted);
     }
 }
 
@@ -2117,7 +2119,7 @@
     const auto& schedule = mScheduler->getVsyncSchedule();
 
     const TimePoint vsyncDeadline = schedule.vsyncDeadlineAfter(frameTime);
-    if (mVsyncModulator->getVsyncConfig().sfOffset > 0) {
+    if (mScheduler->vsyncModulator().getVsyncConfig().sfOffset > 0) {
         return vsyncDeadline;
     }
 
@@ -2231,17 +2233,19 @@
     mPowerHintSessionEnabled = mPowerAdvisor->usePowerHintSession() && activeDisplay &&
             activeDisplay->getPowerMode() == hal::PowerMode::ON;
     if (mPowerHintSessionEnabled) {
-        const auto& display = FTL_FAKE_GUARD(mStateLock, getDefaultDisplayDeviceLocked()).get();
-        const Period vsyncPeriod = Period::fromNs(display->getActiveMode().fps.getPeriodNsecs());
         mPowerAdvisor->setCommitStart(frameTime);
         mPowerAdvisor->setExpectedPresentTime(mExpectedPresentTime);
 
         // Frame delay is how long we should have minus how long we actually have.
-        const Duration idealSfWorkDuration = mVsyncModulator->getVsyncConfig().sfWorkDuration;
+        const Duration idealSfWorkDuration =
+                mScheduler->vsyncModulator().getVsyncConfig().sfWorkDuration;
         const Duration frameDelay = idealSfWorkDuration - (mExpectedPresentTime - frameTime);
 
         mPowerAdvisor->setFrameDelay(frameDelay);
         mPowerAdvisor->setTotalFrameTargetWorkDuration(idealSfWorkDuration);
+
+        const auto& display = FTL_FAKE_GUARD(mStateLock, getDefaultDisplayDeviceLocked()).get();
+        const Period vsyncPeriod = display->getActiveMode().fps.getPeriod();
         mPowerAdvisor->setTargetWorkDuration(vsyncPeriod);
 
         // Send early hint here to make sure there's not another frame pending
@@ -2468,7 +2472,7 @@
 
     // TODO: b/160583065 Enable skip validation when SF caches all client composition layers
     const bool usedGpuComposition = mHadClientComposition || mReusedClientComposition;
-    modulateVsync(&VsyncModulator::onDisplayRefresh, usedGpuComposition);
+    mScheduler->modulateVsync(&VsyncModulator::onDisplayRefresh, usedGpuComposition);
 
     mLayersWithQueuedFrames.clear();
     if (mLayerTracingEnabled && mLayerTracing.flagIsSet(LayerTracing::TRACE_COMPOSITION)) {
@@ -2791,7 +2795,7 @@
     // so we can call commitTransactionsLocked unconditionally.
     // We clear the flags with mStateLock held to guarantee that
     // mCurrentState won't change until the transaction is committed.
-    modulateVsync(&VsyncModulator::onTransactionCommit);
+    mScheduler->modulateVsync(&VsyncModulator::onTransactionCommit);
     commitTransactionsLocked(clearTransactionFlags(eTransactionMask));
 
     mDebugInTransaction = 0;
@@ -3592,19 +3596,18 @@
 }
 
 void SurfaceFlinger::initScheduler(const sp<const DisplayDevice>& display) {
+    using namespace scheduler;
+
     LOG_ALWAYS_FATAL_IF(mScheduler);
 
     const auto activeMode = display->refreshRateSelector().getActiveMode();
     const Fps activeRefreshRate = activeMode.fps;
     mRefreshRateStats =
-            std::make_unique<scheduler::RefreshRateStats>(*mTimeStats, activeRefreshRate,
-                                                          hal::PowerMode::OFF);
+            std::make_unique<RefreshRateStats>(*mTimeStats, activeRefreshRate, hal::PowerMode::OFF);
 
     mVsyncConfiguration = getFactory().createVsyncConfiguration(activeRefreshRate);
-    mVsyncModulator = sp<VsyncModulator>::make(mVsyncConfiguration->getCurrentConfigs());
 
-    using Feature = scheduler::Feature;
-    scheduler::FeatureFlags features;
+    FeatureFlags features;
 
     if (sysprop::use_content_detection_for_refresh_rate(false)) {
         features |= Feature::kContentDetection;
@@ -3620,9 +3623,11 @@
         features |= Feature::kKernelIdleTimer;
     }
 
-    mScheduler = std::make_unique<scheduler::Scheduler>(static_cast<ICompositor&>(*this),
-                                                        static_cast<ISchedulerCallback&>(*this),
-                                                        features);
+    auto modulatorPtr = sp<VsyncModulator>::make(mVsyncConfiguration->getCurrentConfigs());
+
+    mScheduler = std::make_unique<Scheduler>(static_cast<ICompositor&>(*this),
+                                             static_cast<ISchedulerCallback&>(*this), features,
+                                             std::move(modulatorPtr));
     mScheduler->createVsyncSchedule(features);
     mScheduler->registerDisplay(display->getPhysicalId(), display->holdRefreshRateSelector());
 
@@ -3630,15 +3635,17 @@
     mScheduler->startTimers();
 
     const auto configs = mVsyncConfiguration->getCurrentConfigs();
-    const nsecs_t vsyncPeriod = activeRefreshRate.getPeriodNsecs();
+
     mAppConnectionHandle =
-            mScheduler->createConnection("app", mFrameTimeline->getTokenManager(),
-                                         /*workDuration=*/configs.late.appWorkDuration,
-                                         /*readyDuration=*/configs.late.sfWorkDuration);
+            mScheduler->createEventThread(Scheduler::Cycle::Render,
+                                          mFrameTimeline->getTokenManager(),
+                                          /* workDuration */ configs.late.appWorkDuration,
+                                          /* readyDuration */ configs.late.sfWorkDuration);
     mSfConnectionHandle =
-            mScheduler->createConnection("appSf", mFrameTimeline->getTokenManager(),
-                                         /*workDuration=*/std::chrono::nanoseconds(vsyncPeriod),
-                                         /*readyDuration=*/configs.late.sfWorkDuration);
+            mScheduler->createEventThread(Scheduler::Cycle::LastComposite,
+                                          mFrameTimeline->getTokenManager(),
+                                          /* workDuration */ activeRefreshRate.getPeriod(),
+                                          /* readyDuration */ configs.late.sfWorkDuration);
 
     mScheduler->initVsync(mScheduler->getVsyncSchedule().getDispatch(),
                           *mFrameTimeline->getTokenManager(), configs.late.sfWorkDuration);
@@ -3649,20 +3656,10 @@
     mFpsReporter = sp<FpsReporter>::make(*mFrameTimeline, *this);
 }
 
-void SurfaceFlinger::updatePhaseConfiguration(const Fps& refreshRate) {
+void SurfaceFlinger::updatePhaseConfiguration(Fps refreshRate) {
     mVsyncConfiguration->setRefreshRateFps(refreshRate);
-    setVsyncConfig(mVsyncModulator->setVsyncConfigSet(mVsyncConfiguration->getCurrentConfigs()),
-                   refreshRate.getPeriod());
-}
-
-void SurfaceFlinger::setVsyncConfig(const scheduler::VsyncConfig& config, Period vsyncPeriod) {
-    mScheduler->setDuration(mAppConnectionHandle,
-                            /* workDuration */ config.appWorkDuration,
-                            /* readyDuration */ config.sfWorkDuration);
-    mScheduler->setDuration(mSfConnectionHandle,
-                            /* workDuration */ vsyncPeriod,
-                            /* readyDuration */ config.sfWorkDuration);
-    mScheduler->setDuration(config.sfWorkDuration);
+    mScheduler->setVsyncConfigSet(mVsyncConfiguration->getCurrentConfigs(),
+                                  refreshRate.getPeriod());
 }
 
 void SurfaceFlinger::doCommitTransactions() {
@@ -3861,7 +3858,7 @@
 
 void SurfaceFlinger::setTransactionFlags(uint32_t mask, TransactionSchedule schedule,
                                          const sp<IBinder>& applyToken, FrameHint frameHint) {
-    modulateVsync(&VsyncModulator::setTransactionSchedule, schedule, applyToken);
+    mScheduler->modulateVsync(&VsyncModulator::setTransactionSchedule, schedule, applyToken);
 
     if (const bool scheduled = mTransactionFlags.fetch_or(mask) & mask; !scheduled) {
         scheduleCommit(frameHint);
@@ -4066,7 +4063,7 @@
         // We don't want to latch unsignaled if are in early / client composition
         // as it leads to jank due to RenderEngine waiting for unsignaled buffer
         // or window animations being slow.
-        const auto isDefaultVsyncConfig = mVsyncModulator->isVsyncConfigDefault();
+        const auto isDefaultVsyncConfig = mScheduler->vsyncModulator().isVsyncConfigDefault();
         if (!isDefaultVsyncConfig) {
             ALOGV("%s: false (LatchUnsignaledConfig::AutoSingleLayer; !isDefaultVsyncConfig)",
                   __func__);
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index a49c623..3121a34 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -56,6 +56,7 @@
 #include <scheduler/Fps.h>
 #include <scheduler/PresentLatencyTracker.h>
 #include <scheduler/Time.h>
+#include <scheduler/TransactionSchedule.h>
 #include <ui/FenceResult.h>
 
 #include "Display/DisplayMap.h"
@@ -73,7 +74,6 @@
 #include "Scheduler/RefreshRateSelector.h"
 #include "Scheduler/RefreshRateStats.h"
 #include "Scheduler/Scheduler.h"
-#include "Scheduler/VsyncModulator.h"
 #include "SurfaceFlingerFactory.h"
 #include "ThreadContext.h"
 #include "Tracing/LayerTracing.h"
@@ -352,7 +352,6 @@
     friend class TransactionApplicationTest;
     friend class TunnelModeEnabledReporterTest;
 
-    using VsyncModulator = scheduler::VsyncModulator;
     using TransactionSchedule = scheduler::TransactionSchedule;
     using TraverseLayersFunction = std::function<void(const LayerVector::Visitor&)>;
     using RenderAreaFuture = ftl::Future<std::unique_ptr<RenderArea>>;
@@ -470,14 +469,6 @@
         return std::bind(dump, this, _1, _2, _3);
     }
 
-    template <typename... Args,
-              typename Handler = VsyncModulator::VsyncConfigOpt (VsyncModulator::*)(Args...)>
-    void modulateVsync(Handler handler, Args... args) {
-        if (const auto config = (*mVsyncModulator.*handler)(args...)) {
-            setVsyncConfig(*config, mScheduler->getLeaderVsyncPeriod());
-        }
-    }
-
     // Maximum allowed number of display frames that can be set through backdoor
     static const int MAX_ALLOWED_DISPLAY_FRAMES = 2048;
 
@@ -710,8 +701,7 @@
     void updateCursorAsync();
 
     void initScheduler(const sp<const DisplayDevice>&) REQUIRES(kMainThreadContext, mStateLock);
-    void updatePhaseConfiguration(const Fps&) REQUIRES(mStateLock);
-    void setVsyncConfig(const scheduler::VsyncConfig&, Period vsyncPeriod);
+    void updatePhaseConfiguration(Fps) REQUIRES(mStateLock);
 
     /*
      * Transactions
@@ -1290,9 +1280,6 @@
     // Stores phase offsets configured per refresh rate.
     std::unique_ptr<scheduler::VsyncConfiguration> mVsyncConfiguration;
 
-    // Optional to defer construction until PhaseConfiguration is created.
-    sp<VsyncModulator> mVsyncModulator;
-
     std::unique_ptr<scheduler::RefreshRateStats> mRefreshRateStats;
     scheduler::PresentLatencyTracker mPresentLatencyTracker GUARDED_BY(kMainThreadContext);
 
diff --git a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
index 9773644..cdffbb4 100644
--- a/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
+++ b/services/surfaceflinger/fuzzer/surfaceflinger_fuzzers_utils.h
@@ -224,16 +224,16 @@
 class TestableScheduler : public Scheduler, private ICompositor {
 public:
     TestableScheduler(const std::shared_ptr<scheduler::RefreshRateSelector>& selectorPtr,
-                      ISchedulerCallback& callback)
+                      sp<VsyncModulator> modulatorPtr, ISchedulerCallback& callback)
           : TestableScheduler(std::make_unique<android::mock::VsyncController>(),
                               std::make_unique<android::mock::VSyncTracker>(), selectorPtr,
-                              callback) {}
+                              std::move(modulatorPtr), callback) {}
 
     TestableScheduler(std::unique_ptr<VsyncController> controller,
                       std::unique_ptr<VSyncTracker> tracker,
                       std::shared_ptr<RefreshRateSelector> selectorPtr,
-                      ISchedulerCallback& callback)
-          : Scheduler(*this, callback, Feature::kContentDetection) {
+                      sp<VsyncModulator> modulatorPtr, ISchedulerCallback& callback)
+          : Scheduler(*this, callback, Feature::kContentDetection, std::move(modulatorPtr)) {
         mVsyncSchedule.emplace(VsyncSchedule(std::move(tracker), nullptr, std::move(controller)));
 
         const auto displayId = selectorPtr->getActiveMode().modePtr->getPhysicalDisplayId();
@@ -281,6 +281,8 @@
         return Scheduler::onNonPrimaryDisplayModeChanged(handle, mode);
     }
 
+    using Scheduler::setVsyncConfig;
+
 private:
     // ICompositor overrides:
     void configure() override {}
@@ -593,11 +595,11 @@
         mFlinger->updateInputFlinger();
         mFlinger->updateCursorAsync();
 
-        mFlinger->setVsyncConfig({.sfOffset = mFdp.ConsumeIntegral<nsecs_t>(),
-                                  .appOffset = mFdp.ConsumeIntegral<nsecs_t>(),
-                                  .sfWorkDuration = getFuzzedDuration(mFdp),
-                                  .appWorkDuration = getFuzzedDuration(mFdp)},
-                                 getFuzzedDuration(mFdp));
+        mutableScheduler().setVsyncConfig({.sfOffset = mFdp.ConsumeIntegral<nsecs_t>(),
+                                           .appOffset = mFdp.ConsumeIntegral<nsecs_t>(),
+                                           .sfWorkDuration = getFuzzedDuration(mFdp),
+                                           .appWorkDuration = getFuzzedDuration(mFdp)},
+                                          getFuzzedDuration(mFdp));
 
         {
             ftl::FakeGuard guard(kMainThreadContext);
@@ -663,15 +665,17 @@
         mRefreshRateSelector = std::make_shared<scheduler::RefreshRateSelector>(modes, kModeId60);
         const auto fps = mRefreshRateSelector->getActiveMode().modePtr->getFps();
         mFlinger->mVsyncConfiguration = mFactory.createVsyncConfiguration(fps);
-        mFlinger->mVsyncModulator = sp<scheduler::VsyncModulator>::make(
-                mFlinger->mVsyncConfiguration->getCurrentConfigs());
+
         mFlinger->mRefreshRateStats =
                 std::make_unique<scheduler::RefreshRateStats>(*mFlinger->mTimeStats, fps,
                                                               hal::PowerMode::OFF);
 
+        auto modulatorPtr = sp<scheduler::VsyncModulator>::make(
+                mFlinger->mVsyncConfiguration->getCurrentConfigs());
+
         mScheduler = new scheduler::TestableScheduler(std::move(vsyncController),
                                                       std::move(vsyncTracker), mRefreshRateSelector,
-                                                      *(callback ?: this));
+                                                      std::move(modulatorPtr), *(callback ?: this));
 
         mFlinger->mAppConnectionHandle = mScheduler->createConnection(std::move(appEventThread));
         mFlinger->mSfConnectionHandle = mScheduler->createConnection(std::move(sfEventThread));
diff --git a/services/surfaceflinger/tests/unittests/TestableScheduler.h b/services/surfaceflinger/tests/unittests/TestableScheduler.h
index 0f53eb6..0cbfa63 100644
--- a/services/surfaceflinger/tests/unittests/TestableScheduler.h
+++ b/services/surfaceflinger/tests/unittests/TestableScheduler.h
@@ -37,12 +37,12 @@
     TestableScheduler(RefreshRateSelectorPtr selectorPtr, ISchedulerCallback& callback)
           : TestableScheduler(std::make_unique<mock::VsyncController>(),
                               std::make_unique<mock::VSyncTracker>(), std::move(selectorPtr),
-                              callback) {}
+                              /* modulatorPtr */ nullptr, callback) {}
 
     TestableScheduler(std::unique_ptr<VsyncController> controller,
                       std::unique_ptr<VSyncTracker> tracker, RefreshRateSelectorPtr selectorPtr,
-                      ISchedulerCallback& callback)
-          : Scheduler(*this, callback, Feature::kContentDetection) {
+                      sp<VsyncModulator> modulatorPtr, ISchedulerCallback& callback)
+          : Scheduler(*this, callback, Feature::kContentDetection, std::move(modulatorPtr)) {
         mVsyncSchedule.emplace(VsyncSchedule(std::move(tracker),
                                              std::make_unique<mock::VSyncDispatch>(),
                                              std::move(controller)));
@@ -99,6 +99,7 @@
         Scheduler::setLeaderDisplay(displayId);
     }
 
+    auto& mutableVsyncModulator() { return *mVsyncModulator; }
     auto& mutableLayerHistory() { return mLayerHistory; }
 
     size_t layerHistorySize() NO_THREAD_SAFETY_ANALYSIS {
diff --git a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
index 72e0c7b..51d2012 100644
--- a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
+++ b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
@@ -224,8 +224,6 @@
 
         const auto fps = selectorPtr->getActiveMode().fps;
         mFlinger->mVsyncConfiguration = mFactory.createVsyncConfiguration(fps);
-        mFlinger->mVsyncModulator = sp<scheduler::VsyncModulator>::make(
-                mFlinger->mVsyncConfiguration->getCurrentConfigs());
 
         mFlinger->mRefreshRateStats =
                 std::make_unique<scheduler::RefreshRateStats>(*mFlinger->mTimeStats, fps,
@@ -238,16 +236,21 @@
                 ? static_cast<Callback&>(mNoOpSchedulerCallback)
                 : static_cast<Callback&>(mSchedulerCallback);
 
+        auto modulatorPtr = sp<scheduler::VsyncModulator>::make(
+                mFlinger->mVsyncConfiguration->getCurrentConfigs());
+
         if (useNiceMock) {
             mScheduler =
                     new testing::NiceMock<scheduler::TestableScheduler>(std::move(vsyncController),
                                                                         std::move(vsyncTracker),
                                                                         std::move(selectorPtr),
+                                                                        std::move(modulatorPtr),
                                                                         callback);
         } else {
             mScheduler = new scheduler::TestableScheduler(std::move(vsyncController),
                                                           std::move(vsyncTracker),
-                                                          std::move(selectorPtr), callback);
+                                                          std::move(selectorPtr),
+                                                          std::move(modulatorPtr), callback);
         }
 
         mScheduler->initVsync(mScheduler->getVsyncSchedule().getDispatch(), *mTokenManager, 0ms);
@@ -262,8 +265,6 @@
     scheduler::TestableScheduler& mutableScheduler() { return *mScheduler; }
     scheduler::mock::SchedulerCallback& mockSchedulerCallback() { return mSchedulerCallback; }
 
-    auto& mutableVsyncModulator() { return mFlinger->mVsyncModulator; }
-
     using CreateBufferQueueFunction = surfaceflinger::test::Factory::CreateBufferQueueFunction;
     void setCreateBufferQueueFunction(CreateBufferQueueFunction f) {
         mFactory.mCreateBufferQueue = f;
diff --git a/services/surfaceflinger/tests/unittests/TransactionApplicationTest.cpp b/services/surfaceflinger/tests/unittests/TransactionApplicationTest.cpp
index a28d1cd..859f702 100644
--- a/services/surfaceflinger/tests/unittests/TransactionApplicationTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TransactionApplicationTest.cpp
@@ -228,6 +228,11 @@
         EXPECT_EQ(0u, transactionQueue.size());
     }
 
+    void modulateVsync() {
+        static_cast<void>(
+                mFlinger.mutableScheduler().mutableVsyncModulator().onRefreshRateChangeInitiated());
+    }
+
     bool mHasListenerCallbacks = false;
     std::vector<ListenerCallbacks> mCallbacks;
     int mTransactionNumber = 0;
@@ -623,9 +628,7 @@
                                                               layer_state_t::eBufferChanged),
                                   });
 
-    // Get VsyncModulator out of the default config
-    static_cast<void>(mFlinger.mutableVsyncModulator()->onRefreshRateChangeInitiated());
-
+    modulateVsync();
     setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
 }
 
@@ -985,9 +988,7 @@
                                                               layer_state_t::eBufferChanged),
                                   });
 
-    // Get VsyncModulator out of the default config
-    static_cast<void>(mFlinger.mutableVsyncModulator()->onRefreshRateChangeInitiated());
-
+    modulateVsync();
     setTransactionStates({unsignaledTransaction}, kExpectedTransactionsPending);
 }