diff --git a/cmds/bugreportz/readme.md b/cmds/bugreportz/readme.md
index eb0d898..3606827 100644
--- a/cmds/bugreportz/readme.md
+++ b/cmds/bugreportz/readme.md
@@ -1,6 +1,6 @@
 # bugreportz protocol
 
-`bugreportz` is used to generate a zippped bugreport whose path is passed back to `adb`, using
+`bugreportz` is used to generate a zipped bugreport whose path is passed back to `adb`, using
 the simple protocol defined below.
 
 # Version 1.1
diff --git a/services/surfaceflinger/DisplayDevice.cpp b/services/surfaceflinger/DisplayDevice.cpp
index b823e06..a25296c 100644
--- a/services/surfaceflinger/DisplayDevice.cpp
+++ b/services/surfaceflinger/DisplayDevice.cpp
@@ -192,17 +192,16 @@
 }
 
 void DisplayDevice::setActiveMode(DisplayModeId modeId, const display::DisplaySnapshot& snapshot) {
-    const auto modeOpt = snapshot.displayModes().get(modeId);
-    LOG_ALWAYS_FATAL_IF(!modeOpt, "Unknown mode");
+    const auto fpsOpt = snapshot.displayModes().get(modeId).transform(
+            [](const DisplayModePtr& mode) { return mode->getFps(); });
 
-    mActiveMode = modeOpt->get();
-    const Fps fps = mActiveMode->getFps();
+    LOG_ALWAYS_FATAL_IF(!fpsOpt, "Unknown mode");
+    const Fps fps = *fpsOpt;
 
     ATRACE_INT(mActiveModeFPSTrace.c_str(), fps.getIntValue());
 
-    if (mRefreshRateConfigs) {
-        mRefreshRateConfigs->setActiveModeId(modeId);
-    }
+    mRefreshRateConfigs->setActiveModeId(modeId);
+
     if (mRefreshRateOverlay) {
         mRefreshRateOverlay->changeRefreshRate(fps);
     }
@@ -224,10 +223,6 @@
                                                     constraints, outTimeline);
 }
 
-const DisplayModePtr& DisplayDevice::getActiveMode() const {
-    return mActiveMode;
-}
-
 nsecs_t DisplayDevice::getVsyncPeriodFromHWC() const {
     const auto physicalId = getPhysicalId();
     if (!mHwComposer.isConnected(physicalId)) {
@@ -240,7 +235,7 @@
         return vsyncPeriod;
     }
 
-    return getActiveMode()->getFps().getPeriodNsecs();
+    return refreshRateConfigs().getActiveModePtr()->getVsyncPeriod();
 }
 
 nsecs_t DisplayDevice::getRefreshTimestamp() const {
@@ -451,7 +446,7 @@
     mRefreshRateOverlay = std::make_unique<RefreshRateOverlay>(fpsRange, showSpinnner);
     mRefreshRateOverlay->setLayerStack(getLayerStack());
     mRefreshRateOverlay->setViewport(getSize());
-    mRefreshRateOverlay->changeRefreshRate(getActiveMode()->getFps());
+    mRefreshRateOverlay->changeRefreshRate(getActiveMode().getFps());
 }
 
 bool DisplayDevice::onKernelTimerChanged(std::optional<DisplayModeId> desiredModeId,
@@ -492,7 +487,7 @@
     }
 
     // Check if we are already at the desired mode
-    if (getActiveMode()->getId() == info.mode->getId()) {
+    if (refreshRateConfigs().getActiveModePtr()->getId() == info.mode->getId()) {
         return false;
     }
 
diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index d79a6b5..0f52aff 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -189,8 +189,6 @@
     /* ------------------------------------------------------------------------
      * Display mode management.
      */
-    const DisplayModePtr& getActiveMode() const;
-
     struct ActiveModeInfo {
         DisplayModePtr mode;
         scheduler::DisplayModeEvent event = scheduler::DisplayModeEvent::None;
@@ -207,6 +205,10 @@
         return mUpcomingActiveMode;
     }
 
+    const DisplayMode& getActiveMode() const REQUIRES(kMainThreadContext) {
+        return mRefreshRateConfigs->getActiveMode();
+    }
+
     // Precondition: DisplaySnapshot must contain a mode with DisplayModeId.
     void setActiveMode(DisplayModeId, const display::DisplaySnapshot&) REQUIRES(kMainThreadContext);
 
@@ -226,7 +228,7 @@
     }
 
     // Enables an overlay to be displayed with the current refresh rate
-    void enableRefreshRateOverlay(bool enable, bool showSpinner);
+    void enableRefreshRateOverlay(bool enable, bool showSpinner) REQUIRES(kMainThreadContext);
     bool isRefreshRateOverlayEnabled() const { return mRefreshRateOverlay != nullptr; }
     bool onKernelTimerChanged(std::optional<DisplayModeId>, bool timerExpired);
     void animateRefreshRateOverlay();
@@ -265,10 +267,10 @@
 
     static ui::Transform::RotationFlags sPrimaryDisplayRotationFlags;
 
-    // allow initial power mode as null.
+    // Allow nullopt as initial power mode.
     std::optional<hardware::graphics::composer::hal::PowerMode> mPowerMode;
-    DisplayModePtr mActiveMode;
-    std::optional<float> mStagedBrightness = std::nullopt;
+
+    std::optional<float> mStagedBrightness;
     float mBrightness = -1.f;
 
     std::atomic<nsecs_t> mLastHwVsync = 0;
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 9a19f0a..f3551ae 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -680,7 +680,7 @@
 
     sp<IBinder> input(defaultServiceManager()->getService(String16("inputflinger")));
 
-    static_cast<void>(mScheduler->schedule([=] {
+    static_cast<void>(mScheduler->schedule([=]() FTL_FAKE_GUARD(kMainThreadContext) {
         if (input == nullptr) {
             ALOGE("Failed to link to input service");
         } else {
@@ -708,8 +708,9 @@
 
         mBootStage = BootStage::FINISHED;
 
-        if (property_get_bool("sf.debug.show_refresh_rate_overlay", false)) {
-            FTL_FAKE_GUARD(mStateLock, enableRefreshRateOverlay(true));
+        if (base::GetBoolProperty("sf.debug.show_refresh_rate_overlay"s, false)) {
+            ftl::FakeGuard guard(mStateLock);
+            enableRefreshRateOverlay(true);
         }
     }));
 }
@@ -1059,7 +1060,7 @@
 
     const PhysicalDisplayId displayId = snapshot.displayId();
 
-    info->activeDisplayModeId = display->getActiveMode()->getId().value();
+    info->activeDisplayModeId = display->refreshRateConfigs().getActiveModePtr()->getId().value();
     info->activeColorMode = display->getCompositionDisplay()->getState().colorMode;
     info->supportedColorModes = getDisplayColorModes(displayId);
     info->hdrCapabilities = display->getHdrCapabilities();
@@ -1183,7 +1184,7 @@
         return;
     }
 
-    if (display->getActiveMode()->getResolution() != upcomingModeInfo.mode->getResolution()) {
+    if (display->getActiveMode().getResolution() != upcomingModeInfo.mode->getResolution()) {
         auto& state = mCurrentState.displays.editValueFor(display->getDisplayToken());
         // We need to generate new sequenceId in order to recreate the display (and this
         // way the framebuffer).
@@ -1269,7 +1270,7 @@
         ALOGV("%s changing active mode to %d(%s) for display %s", __func__, desiredModeId.value(),
               to_string(*refreshRateOpt).c_str(), to_string(display->getId()).c_str());
 
-        if (display->getActiveMode()->getId() == desiredModeId) {
+        if (display->getActiveMode().getId() == desiredModeId) {
             // we are already in the requested mode, there is nothing left to do
             desiredActiveModeChangeDone(display);
             continue;
@@ -1318,7 +1319,7 @@
         const auto display = getDisplayDeviceLocked(*displayToUpdateImmediately);
         const auto desiredActiveMode = display->getDesiredActiveMode();
         if (desiredActiveMode &&
-            display->getActiveMode()->getId() == desiredActiveMode->mode->getId()) {
+            display->getActiveMode().getId() == desiredActiveMode->mode->getId()) {
             desiredActiveModeChangeDone(display);
         }
     }
@@ -2107,7 +2108,7 @@
             activeDisplay->getPowerMode() == hal::PowerMode::ON;
     if (mPowerHintSessionEnabled) {
         const auto& display = FTL_FAKE_GUARD(mStateLock, getDefaultDisplayDeviceLocked()).get();
-        const Period vsyncPeriod = Period::fromNs(display->getActiveMode()->getVsyncPeriod());
+        const Period vsyncPeriod = Period::fromNs(display->getActiveMode().getVsyncPeriod());
         mPowerAdvisor->setCommitStart(frameTime);
         mPowerAdvisor->setExpectedPresentTime(mExpectedPresentTime);
 
@@ -3084,7 +3085,7 @@
 
 void SurfaceFlinger::updateInternalDisplayVsyncLocked(const sp<DisplayDevice>& activeDisplay) {
     mVsyncConfiguration->reset();
-    const Fps refreshRate = activeDisplay->refreshRateConfigs().getActiveMode().getFps();
+    const Fps refreshRate = activeDisplay->getActiveMode().getFps();
     updatePhaseConfiguration(refreshRate);
     mRefreshRateStats->setRefreshRate(refreshRate);
 }
@@ -3394,11 +3395,13 @@
 void SurfaceFlinger::initScheduler(const sp<const DisplayDevice>& display) {
     LOG_ALWAYS_FATAL_IF(mScheduler);
 
-    const auto currRefreshRate = display->getActiveMode()->getFps();
-    mRefreshRateStats = std::make_unique<scheduler::RefreshRateStats>(*mTimeStats, currRefreshRate,
-                                                                      hal::PowerMode::OFF);
+    const auto activeModePtr = display->refreshRateConfigs().getActiveModePtr();
+    const Fps activeRefreshRate = activeModePtr->getFps();
+    mRefreshRateStats =
+            std::make_unique<scheduler::RefreshRateStats>(*mTimeStats, activeRefreshRate,
+                                                          hal::PowerMode::OFF);
 
-    mVsyncConfiguration = getFactory().createVsyncConfiguration(currRefreshRate);
+    mVsyncConfiguration = getFactory().createVsyncConfiguration(activeRefreshRate);
     mVsyncModulator = sp<VsyncModulator>::make(mVsyncConfiguration->getCurrentConfigs());
 
     using Feature = scheduler::Feature;
@@ -3431,7 +3434,7 @@
     mScheduler->startTimers();
 
     const auto configs = mVsyncConfiguration->getCurrentConfigs();
-    const nsecs_t vsyncPeriod = currRefreshRate.getPeriodNsecs();
+    const nsecs_t vsyncPeriod = activeRefreshRate.getPeriodNsecs();
     mAppConnectionHandle =
             mScheduler->createConnection("app", mFrameTimeline->getTokenManager(),
                                          /*workDuration=*/configs.late.appWorkDuration,
@@ -3459,7 +3462,7 @@
     // This is a bit hacky, but this avoids a back-pointer into the main SF
     // classes from EventThread, and there should be no run-time binder cost
     // anyway since there are no connected apps at this point.
-    mScheduler->onPrimaryDisplayModeChanged(mAppConnectionHandle, display->getActiveMode());
+    mScheduler->onPrimaryDisplayModeChanged(mAppConnectionHandle, activeModePtr);
 }
 
 void SurfaceFlinger::updatePhaseConfiguration(const Fps& refreshRate) {
@@ -5348,10 +5351,10 @@
 
     if (const auto display = getDefaultDisplayDeviceLocked()) {
         std::string fps, xDpi, yDpi;
-        if (const auto activeMode = display->getActiveMode()) {
-            fps = to_string(activeMode->getFps());
+        if (const auto activeModePtr = display->refreshRateConfigs().getActiveModePtr()) {
+            fps = to_string(activeModePtr->getFps());
 
-            const auto dpi = activeMode->getDpi();
+            const auto dpi = activeModePtr->getDpi();
             xDpi = base::StringPrintf("%.2f", dpi.x);
             yDpi = base::StringPrintf("%.2f", dpi.y);
         } else {
@@ -5851,19 +5854,17 @@
                 return NO_ERROR;
             }
             case 1034: {
-                auto future = mScheduler->schedule([&] {
-                    switch (n = data.readInt32()) {
-                        case 0:
-                        case 1:
-                            FTL_FAKE_GUARD(mStateLock,
-                                           enableRefreshRateOverlay(static_cast<bool>(n)));
-                            break;
-                        default: {
-                            reply->writeBool(
-                                    FTL_FAKE_GUARD(mStateLock, isRefreshRateOverlayEnabled()));
-                        }
-                    }
-                });
+                auto future = mScheduler->schedule(
+                        [&]() FTL_FAKE_GUARD(mStateLock) FTL_FAKE_GUARD(kMainThreadContext) {
+                            switch (n = data.readInt32()) {
+                                case 0:
+                                case 1:
+                                    enableRefreshRateOverlay(static_cast<bool>(n));
+                                    break;
+                                default:
+                                    reply->writeBool(isRefreshRateOverlayEnabled());
+                            }
+                        });
 
                 future.wait();
                 return NO_ERROR;
@@ -6804,12 +6805,12 @@
 
     // TODO(b/140204874): Leave the event in until we do proper testing with all apps that might
     // be depending in this callback.
-    const auto activeMode = display->getActiveMode();
+    const auto activeModePtr = display->refreshRateConfigs().getActiveModePtr();
     if (isDisplayActiveLocked(display)) {
-        mScheduler->onPrimaryDisplayModeChanged(mAppConnectionHandle, activeMode);
+        mScheduler->onPrimaryDisplayModeChanged(mAppConnectionHandle, activeModePtr);
         toggleKernelIdleTimer();
     } else {
-        mScheduler->onNonPrimaryDisplayModeChanged(mAppConnectionHandle, activeMode);
+        mScheduler->onNonPrimaryDisplayModeChanged(mAppConnectionHandle, activeModePtr);
     }
 
     auto preferredModeOpt =
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 1f8874d..fdaacf0 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -1340,7 +1340,7 @@
 
     std::unique_ptr<Hwc2::PowerAdvisor> mPowerAdvisor;
 
-    void enableRefreshRateOverlay(bool enable) REQUIRES(mStateLock);
+    void enableRefreshRateOverlay(bool enable) REQUIRES(mStateLock, kMainThreadContext);
 
     // Flag used to set override desired display mode from backdoor
     bool mDebugDisplayModeSetByBackdoor = false;
diff --git a/services/surfaceflinger/tests/unittests/SurfaceFlinger_DisplayModeSwitching.cpp b/services/surfaceflinger/tests/unittests/SurfaceFlinger_DisplayModeSwitching.cpp
index 57937dc..6b7e353 100644
--- a/services/surfaceflinger/tests/unittests/SurfaceFlinger_DisplayModeSwitching.cpp
+++ b/services/surfaceflinger/tests/unittests/SurfaceFlinger_DisplayModeSwitching.cpp
@@ -20,6 +20,7 @@
 
 #include "DisplayTransactionTestHelpers.h"
 
+#include <ftl/fake_guard.h>
 #include <scheduler/Fps.h>
 
 namespace android {
@@ -111,8 +112,10 @@
 }
 
 TEST_F(DisplayModeSwitchingTest, changeRefreshRate_OnActiveDisplay_WithRefreshRequired) {
+    ftl::FakeGuard guard(kMainThreadContext);
+
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     mFlinger.onActiveDisplayChanged(mDisplay);
 
@@ -121,7 +124,7 @@
 
     ASSERT_TRUE(mDisplay->getDesiredActiveMode().has_value());
     ASSERT_EQ(mDisplay->getDesiredActiveMode()->mode->getId(), kModeId90);
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     // Verify that next commit will call setActiveConfigWithConstraints in HWC
     const VsyncPeriodChangeTimeline timeline{.refreshRequired = true};
@@ -134,7 +137,7 @@
 
     Mock::VerifyAndClearExpectations(mComposer);
     ASSERT_TRUE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     // Verify that the next commit will complete the mode change and send
     // a onModeChanged event to the framework.
@@ -144,10 +147,12 @@
     Mock::VerifyAndClearExpectations(mAppEventThread);
 
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId90);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId90);
 }
 
 TEST_F(DisplayModeSwitchingTest, changeRefreshRate_OnActiveDisplay_WithoutRefreshRequired) {
+    ftl::FakeGuard guard(kMainThreadContext);
+
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
 
     mFlinger.onActiveDisplayChanged(mDisplay);
@@ -157,7 +162,7 @@
 
     ASSERT_TRUE(mDisplay->getDesiredActiveMode().has_value());
     ASSERT_EQ(mDisplay->getDesiredActiveMode()->mode->getId(), kModeId90);
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     // Verify that next commit will call setActiveConfigWithConstraints in HWC
     // and complete the mode change.
@@ -172,15 +177,17 @@
     mFlinger.commit();
 
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId90);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId90);
 }
 
 TEST_F(DisplayModeSwitchingTest, twoConsecutiveSetDesiredDisplayModeSpecs) {
+    ftl::FakeGuard guard(kMainThreadContext);
+
     // Test that if we call setDesiredDisplayModeSpecs while a previous mode change
     // is still being processed the later call will be respected.
 
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     mFlinger.onActiveDisplayChanged(mDisplay);
 
@@ -214,12 +221,14 @@
     mFlinger.commit();
 
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId120);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId120);
 }
 
 TEST_F(DisplayModeSwitchingTest, changeResolution_OnActiveDisplay_WithoutRefreshRequired) {
+    ftl::FakeGuard guard(kMainThreadContext);
+
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     mFlinger.onActiveDisplayChanged(mDisplay);
 
@@ -228,7 +237,7 @@
 
     ASSERT_TRUE(mDisplay->getDesiredActiveMode().has_value());
     ASSERT_EQ(mDisplay->getDesiredActiveMode()->mode->getId(), kModeId90_4K);
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId60);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId60);
 
     // Verify that next commit will call setActiveConfigWithConstraints in HWC
     // and complete the mode change.
@@ -263,7 +272,7 @@
     mDisplay = mFlinger.getDisplay(displayToken);
 
     ASSERT_FALSE(mDisplay->getDesiredActiveMode().has_value());
-    ASSERT_EQ(mDisplay->getActiveMode()->getId(), kModeId90_4K);
+    ASSERT_EQ(mDisplay->getActiveMode().getId(), kModeId90_4K);
 }
 
 } // namespace
diff --git a/services/surfaceflinger/tests/unittests/SurfaceFlinger_SetupNewDisplayDeviceInternalTest.cpp b/services/surfaceflinger/tests/unittests/SurfaceFlinger_SetupNewDisplayDeviceInternalTest.cpp
index ec2c2b4..073c459 100644
--- a/services/surfaceflinger/tests/unittests/SurfaceFlinger_SetupNewDisplayDeviceInternalTest.cpp
+++ b/services/surfaceflinger/tests/unittests/SurfaceFlinger_SetupNewDisplayDeviceInternalTest.cpp
@@ -17,6 +17,8 @@
 #undef LOG_TAG
 #define LOG_TAG "LibSurfaceFlingerUnittests"
 
+#include <ftl/fake_guard.h>
+
 #include "DisplayHardware/DisplayMode.h"
 
 #include "DisplayTransactionTestHelpers.h"
@@ -265,7 +267,7 @@
     // --------------------------------------------------------------------
     // Postconditions
 
-    ASSERT_TRUE(device != nullptr);
+    ASSERT_NE(nullptr, device);
     EXPECT_EQ(Case::Display::DISPLAY_ID::get(), device->getId());
     EXPECT_EQ(static_cast<bool>(Case::Display::VIRTUAL), device->isVirtual());
     EXPECT_EQ(static_cast<bool>(Case::Display::SECURE), device->isSecure());
@@ -282,8 +284,8 @@
               device->receivesInput());
 
     if constexpr (Case::Display::CONNECTION_TYPE::value) {
-        EXPECT_NE(nullptr, device->getActiveMode());
-        EXPECT_EQ(Case::Display::HWC_ACTIVE_CONFIG_ID, device->getActiveMode()->getHwcId());
+        ftl::FakeGuard guard(kMainThreadContext);
+        EXPECT_EQ(Case::Display::HWC_ACTIVE_CONFIG_ID, device->getActiveMode().getHwcId());
     }
 }