diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index fac2c65..857071c 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -194,8 +194,6 @@
 
 std::unique_ptr<LayerHistory> Scheduler::createLayerHistory(
         const scheduler::RefreshRateConfigs& configs) {
-    if (!configs.canSwitch()) return nullptr;
-
     return std::make_unique<scheduler::LayerHistory>(configs);
 }
 
@@ -579,8 +577,6 @@
 }
 
 void Scheduler::registerLayer(Layer* layer) {
-    if (!mLayerHistory) return;
-
     scheduler::LayerHistory::LayerVoteType voteType;
 
     if (!mOptions.useContentDetection ||
@@ -600,26 +596,22 @@
 }
 
 void Scheduler::deregisterLayer(Layer* layer) {
-    if (mLayerHistory) {
-        mLayerHistory->deregisterLayer(layer);
-    }
+    mLayerHistory->deregisterLayer(layer);
 }
 
 void Scheduler::recordLayerHistory(Layer* layer, nsecs_t presentTime,
                                    LayerHistory::LayerUpdateType updateType) {
-    if (mLayerHistory) {
+    if (mRefreshRateConfigs.canSwitch()) {
         mLayerHistory->record(layer, presentTime, systemTime(), updateType);
     }
 }
 
 void Scheduler::setModeChangePending(bool pending) {
-    if (mLayerHistory) {
-        mLayerHistory->setModeChangePending(pending);
-    }
+    mLayerHistory->setModeChangePending(pending);
 }
 
 void Scheduler::chooseRefreshRateForContent() {
-    if (!mLayerHistory) return;
+    if (!mRefreshRateConfigs.canSwitch()) return;
 
     ATRACE_CALL();
 
@@ -691,9 +683,7 @@
 
     // Display Power event will boost the refresh rate to performance.
     // Clear Layer History to get fresh FPS detection
-    if (mLayerHistory) {
-        mLayerHistory->clear();
-    }
+    mLayerHistory->clear();
 }
 
 void Scheduler::kernelIdleTimerCallback(TimerState state) {
@@ -732,9 +722,7 @@
     // NOTE: Instead of checking all the layers, we should be checking the layer
     // that is currently on top. b/142507166 will give us this capability.
     if (handleTimerStateChanged(&mFeatures.touch, touch)) {
-        if (mLayerHistory) {
-            mLayerHistory->clear();
-        }
+        mLayerHistory->clear();
     }
     ATRACE_INT("TouchState", static_cast<int>(touch));
 }
@@ -908,9 +896,7 @@
 }
 
 void Scheduler::onPrimaryDisplayAreaChanged(uint32_t displayArea) {
-    if (mLayerHistory) {
-        mLayerHistory->setDisplayArea(displayArea);
-    }
+    mLayerHistory->setDisplayArea(displayArea);
 }
 
 void Scheduler::setPreferredRefreshRateForUid(FrameRateOverride frameRateOverride) {
diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index 49d3d93..30a3253 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -268,7 +268,7 @@
     VsyncSchedule mVsyncSchedule;
 
     // Used to choose refresh rate if content detection is enabled.
-    const std::unique_ptr<LayerHistory> mLayerHistory;
+    std::unique_ptr<LayerHistory> mLayerHistory;
 
     // Timer that records time between requests for next vsync.
     std::optional<scheduler::OneShotTimer> mIdleTimer;
diff --git a/services/surfaceflinger/tests/unittests/SchedulerTest.cpp b/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
index 38e503f..8ad8ea4 100644
--- a/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
+++ b/services/surfaceflinger/tests/unittests/SchedulerTest.cpp
@@ -51,9 +51,18 @@
 
     SchedulerTest();
 
-    const scheduler::RefreshRateConfigs
-            mConfigs{{DisplayMode::Builder(0).setVsyncPeriod(16'666'667).setGroup(0).build()},
-                     DisplayModeId(0)};
+    const DisplayModePtr mode60 = DisplayMode::Builder(0)
+                                          .setId(DisplayModeId(0))
+                                          .setVsyncPeriod(Fps(60.f).getPeriodNsecs())
+                                          .setGroup(0)
+                                          .build();
+    const DisplayModePtr mode120 = DisplayMode::Builder(1)
+                                           .setId(DisplayModeId(1))
+                                           .setVsyncPeriod(Fps(120.f).getPeriodNsecs())
+                                           .setGroup(0)
+                                           .build();
+
+    scheduler::RefreshRateConfigs mConfigs{{mode60}, mode60->getId()};
 
     mock::SchedulerCallback mSchedulerCallback;
 
@@ -149,15 +158,14 @@
     EXPECT_EQ(kEventConnections, mScheduler->getEventThreadConnectionCount(mConnectionHandle));
 }
 
-TEST_F(SchedulerTest, noLayerHistory) {
-    // Layer history should not be created if there is a single config.
-    ASSERT_FALSE(mScheduler->hasLayerHistory());
-
+TEST_F(SchedulerTest, chooseRefreshRateForContentIsNoopWhenModeSwitchingIsNotSupported) {
+    // The layer is registered at creation time and deregistered at destruction time.
     sp<mock::MockLayer> layer = sp<mock::MockLayer>::make(mFlinger.flinger());
 
-    // Content detection should be no-op.
-    mScheduler->registerLayer(layer.get());
+    // recordLayerHistory should be a noop
+    ASSERT_EQ(static_cast<size_t>(0), mScheduler->getNumActiveLayers());
     mScheduler->recordLayerHistory(layer.get(), 0, LayerHistory::LayerUpdateType::Buffer);
+    ASSERT_EQ(static_cast<size_t>(0), mScheduler->getNumActiveLayers());
 
     constexpr bool kPowerStateNormal = true;
     mScheduler->setDisplayPowerState(kPowerStateNormal);
@@ -169,6 +177,18 @@
     mScheduler->chooseRefreshRateForContent();
 }
 
+TEST_F(SchedulerTest, updateDisplayModes) {
+    ASSERT_EQ(static_cast<size_t>(0), mScheduler->layerHistorySize());
+    sp<mock::MockLayer> layer = sp<mock::MockLayer>::make(mFlinger.flinger());
+    ASSERT_EQ(static_cast<size_t>(1), mScheduler->layerHistorySize());
+
+    mConfigs.updateDisplayModes({mode60, mode120}, /* activeMode */ mode60->getId());
+
+    ASSERT_EQ(static_cast<size_t>(0), mScheduler->getNumActiveLayers());
+    mScheduler->recordLayerHistory(layer.get(), 0, LayerHistory::LayerUpdateType::Buffer);
+    ASSERT_EQ(static_cast<size_t>(1), mScheduler->getNumActiveLayers());
+}
+
 TEST_F(SchedulerTest, testDispatchCachedReportedMode) {
     // If the optional fields are cleared, the function should return before
     // onModeChange is called.
diff --git a/services/surfaceflinger/tests/unittests/TestableScheduler.h b/services/surfaceflinger/tests/unittests/TestableScheduler.h
index 3f9dd01..41fd6e3 100644
--- a/services/surfaceflinger/tests/unittests/TestableScheduler.h
+++ b/services/surfaceflinger/tests/unittests/TestableScheduler.h
@@ -64,6 +64,11 @@
         return mutableLayerHistory()->mLayerInfos.size();
     }
 
+    size_t getNumActiveLayers() NO_THREAD_SAFETY_ANALYSIS {
+        if (!mLayerHistory) return 0;
+        return mutableLayerHistory()->mActiveLayersEnd;
+    }
+
     void replaceTouchTimer(int64_t millis) {
         if (mTouchTimer) {
             mTouchTimer.reset();