Merge "Send raw coordinates to client but scale when getting relative"
diff --git a/libs/binder/BpBinder.cpp b/libs/binder/BpBinder.cpp
index 238c9dc..f16c39c 100644
--- a/libs/binder/BpBinder.cpp
+++ b/libs/binder/BpBinder.cpp
@@ -435,7 +435,8 @@
     Vector<Obituary>* obits = mObituaries;
     if(obits != nullptr) {
         if (!obits->isEmpty()) {
-            ALOGI("onLastStrongRef automatically unlinking death recipients");
+            ALOGI("onLastStrongRef automatically unlinking death recipients: %s",
+                  mDescriptorCache.size() ? String8(mDescriptorCache).c_str() : "<uncached descriptor>");
         }
 
         if (ipc) ipc->clearDeathNotification(mHandle, this);
diff --git a/libs/binder/ndk/test/Android.bp b/libs/binder/ndk/test/Android.bp
index e598eec..513d8c2 100644
--- a/libs/binder/ndk/test/Android.bp
+++ b/libs/binder/ndk/test/Android.bp
@@ -59,6 +59,9 @@
     name: "libbinder_ndk_unit_test",
     defaults: ["test_libbinder_ndk_test_defaults"],
     srcs: ["libbinder_ndk_unit_test.cpp"],
+    static_libs: [
+        "IBinderNdkUnitTest-ndk_platform",
+    ],
     test_suites: ["general-tests"],
     require_root: true,
 
@@ -93,3 +96,11 @@
         "IBinderVendorDoubleLoadTest.aidl",
     ],
 }
+
+aidl_interface {
+    name: "IBinderNdkUnitTest",
+    srcs: [
+        "IBinderNdkUnitTest.aidl",
+        "IEmpty.aidl",
+    ],
+}
diff --git a/libs/binder/ndk/test/IBinderNdkUnitTest.aidl b/libs/binder/ndk/test/IBinderNdkUnitTest.aidl
new file mode 100644
index 0000000..6e8e463
--- /dev/null
+++ b/libs/binder/ndk/test/IBinderNdkUnitTest.aidl
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+// This AIDL is to test things that can't be tested in CtsNdkBinderTestCases
+// because it requires libbinder_ndk implementation details or APIs not
+// available to apps. Please prefer adding tests to CtsNdkBinderTestCases
+// over here.
+
+import IEmpty;
+
+interface IBinderNdkUnitTest {
+    void takeInterface(IEmpty test);
+    void forceFlushCommands();
+}
diff --git a/libs/binder/ndk/test/IEmpty.aidl b/libs/binder/ndk/test/IEmpty.aidl
new file mode 100644
index 0000000..95e4341
--- /dev/null
+++ b/libs/binder/ndk/test/IEmpty.aidl
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+interface IEmpty { }
diff --git a/libs/binder/ndk/test/libbinder_ndk_unit_test.cpp b/libs/binder/ndk/test/libbinder_ndk_unit_test.cpp
index 8aba411..51dd169 100644
--- a/libs/binder/ndk/test/libbinder_ndk_unit_test.cpp
+++ b/libs/binder/ndk/test/libbinder_ndk_unit_test.cpp
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#include <aidl/BnBinderNdkUnitTest.h>
+#include <aidl/BnEmpty.h>
 #include <android-base/logging.h>
 #include <android/binder_ibinder_jni.h>
 #include <android/binder_manager.h>
@@ -21,6 +23,10 @@
 #include <gtest/gtest.h>
 #include <iface/iface.h>
 
+// warning: this is assuming that libbinder_ndk is using the same copy
+// of libbinder that we are.
+#include <binder/IPCThreadState.h>
+
 #include <sys/prctl.h>
 #include <chrono>
 #include <condition_variable>
@@ -29,7 +35,38 @@
 using ::android::sp;
 
 constexpr char kExistingNonNdkService[] = "SurfaceFlinger";
+constexpr char kBinderNdkUnitTestService[] = "BinderNdkUnitTest";
 
+class MyBinderNdkUnitTest : public aidl::BnBinderNdkUnitTest {
+    ndk::ScopedAStatus takeInterface(const std::shared_ptr<aidl::IEmpty>& empty) {
+        (void)empty;
+        return ndk::ScopedAStatus::ok();
+    }
+    ndk::ScopedAStatus forceFlushCommands() {
+        // warning: this is assuming that libbinder_ndk is using the same copy
+        // of libbinder that we are.
+        android::IPCThreadState::self()->flushCommands();
+        return ndk::ScopedAStatus::ok();
+    }
+};
+
+int generatedService() {
+    ABinderProcess_setThreadPoolMaxThreadCount(0);
+
+    auto service = ndk::SharedRefBase::make<MyBinderNdkUnitTest>();
+    binder_status_t status =
+            AServiceManager_addService(service->asBinder().get(), kBinderNdkUnitTestService);
+
+    if (status != STATUS_OK) {
+        LOG(FATAL) << "Could not register: " << status << " " << kBinderNdkUnitTestService;
+    }
+
+    ABinderProcess_joinThreadPool();
+
+    return 1;  // should not return
+}
+
+// manually-written parceling class considered bad practice
 class MyFoo : public IFoo {
     binder_status_t doubleNumber(int32_t in, int32_t* out) override {
         *out = 2 * in;
@@ -43,7 +80,7 @@
     }
 };
 
-int service(const char* instance) {
+int manualService(const char* instance) {
     ABinderProcess_setThreadPoolMaxThreadCount(0);
 
     // Strong reference to MyFoo kept by service manager.
@@ -225,16 +262,54 @@
     EXPECT_EQ(IFoo::getService(kInstanceName1), IFoo::getService(kInstanceName2));
 }
 
+TEST(NdkBinder, SentAidlBinderCanBeDestroyed) {
+    static volatile bool destroyed = false;
+    static std::mutex dMutex;
+    static std::condition_variable cv;
+
+    class MyEmpty : public aidl::BnEmpty {
+        virtual ~MyEmpty() {
+            destroyed = true;
+            cv.notify_one();
+        }
+    };
+
+    std::shared_ptr<MyEmpty> empty = ndk::SharedRefBase::make<MyEmpty>();
+
+    ndk::SpAIBinder binder(AServiceManager_getService(kBinderNdkUnitTestService));
+    std::shared_ptr<aidl::IBinderNdkUnitTest> service =
+            aidl::IBinderNdkUnitTest::fromBinder(binder);
+
+    EXPECT_FALSE(destroyed);
+
+    service->takeInterface(empty);
+    service->forceFlushCommands();
+    empty = nullptr;
+
+    // give other binder thread time to process commands
+    {
+        using namespace std::chrono_literals;
+        std::unique_lock<std::mutex> lk(dMutex);
+        cv.wait_for(lk, 1s, [] { return destroyed; });
+    }
+
+    EXPECT_TRUE(destroyed);
+}
+
 int main(int argc, char* argv[]) {
     ::testing::InitGoogleTest(&argc, argv);
 
     if (fork() == 0) {
         prctl(PR_SET_PDEATHSIG, SIGHUP);
-        return service(IFoo::kInstanceNameToDieFor);
+        return manualService(IFoo::kInstanceNameToDieFor);
     }
     if (fork() == 0) {
         prctl(PR_SET_PDEATHSIG, SIGHUP);
-        return service(IFoo::kSomeInstanceName);
+        return manualService(IFoo::kSomeInstanceName);
+    }
+    if (fork() == 0) {
+        prctl(PR_SET_PDEATHSIG, SIGHUP);
+        return generatedService();
     }
 
     ABinderProcess_setThreadPoolMaxThreadCount(1);  // to recieve death notifications/callbacks
diff --git a/libs/gui/BLASTBufferQueue.cpp b/libs/gui/BLASTBufferQueue.cpp
index 3f359f5..4e62da7 100644
--- a/libs/gui/BLASTBufferQueue.cpp
+++ b/libs/gui/BLASTBufferQueue.cpp
@@ -83,6 +83,7 @@
         if (stats.size() > 0) {
             mPendingReleaseItem.releaseFence = stats[0].previousReleaseFence;
             mTransformHint = stats[0].transformHint;
+            mBufferItemConsumer->setTransformHint(mTransformHint);
         } else {
             ALOGE("Warning: no SurfaceControlStats returned in BLASTBufferQueue callback");
             mPendingReleaseItem.releaseFence = nullptr;
@@ -151,7 +152,7 @@
                        bufferItem.mFence ? new Fence(bufferItem.mFence->dup()) : Fence::NO_FENCE);
     t->addTransactionCompletedCallback(transactionCallbackThunk, static_cast<void*>(this));
 
-    t->setFrame(mSurfaceControl, {0, 0, (int32_t)buffer->getWidth(), (int32_t)buffer->getHeight()});
+    t->setFrame(mSurfaceControl, {0, 0, mWidth, mHeight});
     t->setCrop(mSurfaceControl, computeCrop(bufferItem));
     t->setTransform(mSurfaceControl, bufferItem.mTransform);
     t->setTransformToDisplayInverse(mSurfaceControl, bufferItem.mTransformToDisplayInverse);
diff --git a/services/surfaceflinger/ColorLayer.cpp b/services/surfaceflinger/ColorLayer.cpp
index 04854d0..dbdfd5b 100644
--- a/services/surfaceflinger/ColorLayer.cpp
+++ b/services/surfaceflinger/ColorLayer.cpp
@@ -61,7 +61,7 @@
 }
 
 bool ColorLayer::isVisible() const {
-    return !isHiddenByPolicy() && getAlpha() > 0.0f;
+    return !isHiddenByPolicy() && getAlpha() > 0.0_hf;
 }
 
 bool ColorLayer::setColor(const half3& color) {
@@ -104,7 +104,9 @@
 }
 
 bool ColorLayer::isOpaque(const Layer::State& s) const {
-    return (s.flags & layer_state_t::eLayerOpaque) != 0;
+    // Consider the layer to be opaque if its opaque flag is set or its effective
+    // alpha (considering the alpha of its parents as well) is 1.0;
+    return (s.flags & layer_state_t::eLayerOpaque) != 0 || getAlpha() == 1.0_hf;
 }
 
 ui::Dataspace ColorLayer::getDataSpace() const {
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 50c88f2..cedab59 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -1804,6 +1804,15 @@
     }
 }
 
+void Layer::traverse(LayerVector::StateSet state, const LayerVector::Visitor& visitor) {
+    visitor(this);
+    const LayerVector& children =
+            state == LayerVector::StateSet::Drawing ? mDrawingChildren : mCurrentChildren;
+    for (const sp<Layer>& child : children) {
+        child->traverse(state, visitor);
+    }
+}
+
 LayerVector Layer::makeChildrenTraversalList(LayerVector::StateSet stateSet,
                                              const std::vector<Layer*>& layersInTree) {
     LOG_ALWAYS_FATAL_IF(stateSet == LayerVector::StateSet::Invalid,
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index 24e1d25..da3df8f 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -679,6 +679,15 @@
 
     renderengine::ShadowSettings getShadowSettings(const Rect& viewport) const;
 
+    /**
+     * Traverse this layer and it's hierarchy of children directly. Unlike traverseInZOrder
+     * which will not emit children who have relativeZOrder to another layer, this method
+     * just directly emits all children. It also emits them in no particular order.
+     * So this method is not suitable for graphical operations, as it doesn't represent
+     * the scene state, but it's also more efficient than traverseInZOrder and so useful for
+     * book-keeping.
+     */
+    void traverse(LayerVector::StateSet stateSet, const LayerVector::Visitor& visitor);
     void traverseInReverseZOrder(LayerVector::StateSet stateSet,
                                  const LayerVector::Visitor& visitor);
     void traverseInZOrder(LayerVector::StateSet stateSet, const LayerVector::Visitor& visitor);
diff --git a/services/surfaceflinger/LayerVector.cpp b/services/surfaceflinger/LayerVector.cpp
index 7c959b9..9b94920 100644
--- a/services/surfaceflinger/LayerVector.cpp
+++ b/services/surfaceflinger/LayerVector.cpp
@@ -86,6 +86,14 @@
         layer->traverseInReverseZOrder(stateSet, visitor);
      }
 }
+
+void LayerVector::traverse(const Visitor& visitor) const {
+    for (auto i = static_cast<int64_t>(size()) - 1; i >= 0; i--) {
+        const auto& layer = (*this)[i];
+        layer->traverse(mStateSet, visitor);
+    }
+}
+
 } // namespace android
 
 // TODO(b/129481165): remove the #pragma below and fix conversion issues
diff --git a/services/surfaceflinger/LayerVector.h b/services/surfaceflinger/LayerVector.h
index 88d7711..a531f4f 100644
--- a/services/surfaceflinger/LayerVector.h
+++ b/services/surfaceflinger/LayerVector.h
@@ -50,7 +50,7 @@
     using Visitor = std::function<void(Layer*)>;
     void traverseInReverseZOrder(StateSet stateSet, const Visitor& visitor) const;
     void traverseInZOrder(StateSet stateSet, const Visitor& visitor) const;
-
+    void traverse(const Visitor& visitor) const;
 private:
     const StateSet mStateSet;
 };
diff --git a/services/surfaceflinger/Scheduler/VSyncPredictor.cpp b/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
index ac32633..e688415 100644
--- a/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncPredictor.cpp
@@ -71,12 +71,12 @@
     return std::get<0>(mRateMap.find(mIdealPeriod)->second);
 }
 
-void VSyncPredictor::addVsyncTimestamp(nsecs_t timestamp) {
+bool VSyncPredictor::addVsyncTimestamp(nsecs_t timestamp) {
     std::lock_guard<std::mutex> lk(mMutex);
 
     if (!validate(timestamp)) {
         ALOGV("timestamp was too far off the last known timestamp");
-        return;
+        return false;
     }
 
     if (timestamps.size() != kHistorySize) {
@@ -89,7 +89,7 @@
 
     if (timestamps.size() < kMinimumSamplesForPrediction) {
         mRateMap[mIdealPeriod] = {mIdealPeriod, 0};
-        return;
+        return true;
     }
 
     // This is a 'simple linear regression' calculation of Y over X, with Y being the
@@ -143,7 +143,7 @@
 
     if (CC_UNLIKELY(bottom == 0)) {
         it->second = {mIdealPeriod, 0};
-        return;
+        return false;
     }
 
     nsecs_t const anticipatedPeriod = top / bottom * kScalingFactor;
@@ -156,6 +156,7 @@
 
     ALOGV("model update ts: %" PRId64 " slope: %" PRId64 " intercept: %" PRId64, timestamp,
           anticipatedPeriod, intercept);
+    return true;
 }
 
 nsecs_t VSyncPredictor::nextAnticipatedVSyncTimeFrom(nsecs_t timePoint) const {
diff --git a/services/surfaceflinger/Scheduler/VSyncPredictor.h b/services/surfaceflinger/Scheduler/VSyncPredictor.h
index e366555..532fe9e 100644
--- a/services/surfaceflinger/Scheduler/VSyncPredictor.h
+++ b/services/surfaceflinger/Scheduler/VSyncPredictor.h
@@ -38,7 +38,7 @@
                    uint32_t outlierTolerancePercent);
     ~VSyncPredictor();
 
-    void addVsyncTimestamp(nsecs_t timestamp) final;
+    bool addVsyncTimestamp(nsecs_t timestamp) final;
     nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t timePoint) const final;
     nsecs_t currentPeriod() const final;
     void resetModel() final;
diff --git a/services/surfaceflinger/Scheduler/VSyncReactor.cpp b/services/surfaceflinger/Scheduler/VSyncReactor.cpp
index 53fa212..70e4760 100644
--- a/services/surfaceflinger/Scheduler/VSyncReactor.cpp
+++ b/services/surfaceflinger/Scheduler/VSyncReactor.cpp
@@ -130,10 +130,11 @@
     }
 
     std::lock_guard<std::mutex> lk(mMutex);
-    if (mIgnorePresentFences) {
+    if (mExternalIgnoreFences || mInternalIgnoreFences) {
         return true;
     }
 
+    bool timestampAccepted = true;
     for (auto it = mUnfiredFences.begin(); it != mUnfiredFences.end();) {
         auto const time = (*it)->getCachedSignalTime();
         if (time == Fence::SIGNAL_TIME_PENDING) {
@@ -141,7 +142,8 @@
         } else if (time == Fence::SIGNAL_TIME_INVALID) {
             it = mUnfiredFences.erase(it);
         } else {
-            mTracker->addVsyncTimestamp(time);
+            timestampAccepted &= mTracker->addVsyncTimestamp(time);
+
             it = mUnfiredFences.erase(it);
         }
     }
@@ -152,7 +154,13 @@
         }
         mUnfiredFences.push_back(fence);
     } else {
-        mTracker->addVsyncTimestamp(signalTime);
+        timestampAccepted &= mTracker->addVsyncTimestamp(signalTime);
+    }
+
+    if (!timestampAccepted) {
+        mMoreSamplesNeeded = true;
+        setIgnorePresentFencesInternal(true);
+        mPeriodConfirmationInProgress = true;
     }
 
     return mMoreSamplesNeeded;
@@ -160,8 +168,17 @@
 
 void VSyncReactor::setIgnorePresentFences(bool ignoration) {
     std::lock_guard<std::mutex> lk(mMutex);
-    mIgnorePresentFences = ignoration;
-    if (mIgnorePresentFences == true) {
+    mExternalIgnoreFences = ignoration;
+    updateIgnorePresentFencesInternal();
+}
+
+void VSyncReactor::setIgnorePresentFencesInternal(bool ignoration) {
+    mInternalIgnoreFences = ignoration;
+    updateIgnorePresentFencesInternal();
+}
+
+void VSyncReactor::updateIgnorePresentFencesInternal() {
+    if (mExternalIgnoreFences || mInternalIgnoreFences) {
         mUnfiredFences.clear();
     }
 }
@@ -177,14 +194,18 @@
 }
 
 void VSyncReactor::startPeriodTransition(nsecs_t newPeriod) {
+    mPeriodConfirmationInProgress = true;
     mPeriodTransitioningTo = newPeriod;
     mMoreSamplesNeeded = true;
+    setIgnorePresentFencesInternal(true);
 }
 
 void VSyncReactor::endPeriodTransition() {
-    mPeriodTransitioningTo.reset();
-    mLastHwVsync.reset();
+    setIgnorePresentFencesInternal(false);
     mMoreSamplesNeeded = false;
+    mPeriodTransitioningTo.reset();
+    mPeriodConfirmationInProgress = false;
+    mLastHwVsync.reset();
 }
 
 void VSyncReactor::setPeriod(nsecs_t period) {
@@ -208,27 +229,33 @@
 
 void VSyncReactor::endResync() {}
 
-bool VSyncReactor::periodChangeDetected(nsecs_t vsync_timestamp) {
-    if (!mLastHwVsync || !mPeriodTransitioningTo) {
+bool VSyncReactor::periodConfirmed(nsecs_t vsync_timestamp) {
+    if (!mLastHwVsync || !mPeriodConfirmationInProgress) {
         return false;
     }
+    auto const period = mPeriodTransitioningTo ? *mPeriodTransitioningTo : getPeriod();
+
+    static constexpr int allowancePercent = 10;
+    static constexpr std::ratio<allowancePercent, 100> allowancePercentRatio;
+    auto const allowance = period * allowancePercentRatio.num / allowancePercentRatio.den;
     auto const distance = vsync_timestamp - *mLastHwVsync;
-    return std::abs(distance - *mPeriodTransitioningTo) < std::abs(distance - getPeriod());
+    return std::abs(distance - period) < allowance;
 }
 
 bool VSyncReactor::addResyncSample(nsecs_t timestamp, bool* periodFlushed) {
     assert(periodFlushed);
 
     std::lock_guard<std::mutex> lk(mMutex);
-    if (periodChangeDetected(timestamp)) {
-        mTracker->setPeriod(*mPeriodTransitioningTo);
-        for (auto& entry : mCallbacks) {
-            entry.second->setPeriod(*mPeriodTransitioningTo);
+    if (periodConfirmed(timestamp)) {
+        if (mPeriodTransitioningTo) {
+            mTracker->setPeriod(*mPeriodTransitioningTo);
+            for (auto& entry : mCallbacks) {
+                entry.second->setPeriod(*mPeriodTransitioningTo);
+            }
+            *periodFlushed = true;
         }
-
         endPeriodTransition();
-        *periodFlushed = true;
-    } else if (mPeriodTransitioningTo) {
+    } else if (mPeriodConfirmationInProgress) {
         mLastHwVsync = timestamp;
         mMoreSamplesNeeded = true;
         *periodFlushed = false;
diff --git a/services/surfaceflinger/Scheduler/VSyncReactor.h b/services/surfaceflinger/Scheduler/VSyncReactor.h
index f318dcb..5b79f35 100644
--- a/services/surfaceflinger/Scheduler/VSyncReactor.h
+++ b/services/surfaceflinger/Scheduler/VSyncReactor.h
@@ -61,9 +61,11 @@
     void reset() final;
 
 private:
+    void setIgnorePresentFencesInternal(bool ignoration) REQUIRES(mMutex);
+    void updateIgnorePresentFencesInternal() REQUIRES(mMutex);
     void startPeriodTransition(nsecs_t newPeriod) REQUIRES(mMutex);
     void endPeriodTransition() REQUIRES(mMutex);
-    bool periodChangeDetected(nsecs_t vsync_timestamp) REQUIRES(mMutex);
+    bool periodConfirmed(nsecs_t vsync_timestamp) REQUIRES(mMutex);
 
     std::unique_ptr<Clock> const mClock;
     std::unique_ptr<VSyncTracker> const mTracker;
@@ -71,10 +73,12 @@
     size_t const mPendingLimit;
 
     std::mutex mMutex;
-    bool mIgnorePresentFences GUARDED_BY(mMutex) = false;
+    bool mInternalIgnoreFences GUARDED_BY(mMutex) = false;
+    bool mExternalIgnoreFences GUARDED_BY(mMutex) = false;
     std::vector<std::shared_ptr<FenceTime>> mUnfiredFences GUARDED_BY(mMutex);
 
     bool mMoreSamplesNeeded GUARDED_BY(mMutex) = false;
+    bool mPeriodConfirmationInProgress GUARDED_BY(mMutex) = false;
     std::optional<nsecs_t> mPeriodTransitioningTo GUARDED_BY(mMutex);
     std::optional<nsecs_t> mLastHwVsync GUARDED_BY(mMutex);
 
diff --git a/services/surfaceflinger/Scheduler/VSyncTracker.h b/services/surfaceflinger/Scheduler/VSyncTracker.h
index 2b27884..a25b8a9 100644
--- a/services/surfaceflinger/Scheduler/VSyncTracker.h
+++ b/services/surfaceflinger/Scheduler/VSyncTracker.h
@@ -33,8 +33,10 @@
      * to the model.
      *
      * \param [in] timestamp    The timestamp when the vsync signal was.
+     * \return                  True if the timestamp was consistent with the internal model,
+     *                          False otherwise
      */
-    virtual void addVsyncTimestamp(nsecs_t timestamp) = 0;
+    virtual bool addVsyncTimestamp(nsecs_t timestamp) = 0;
 
     /*
      * Access the next anticipated vsync time such that the anticipated time >= timePoint.
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 62d47e1..61d197c 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2059,7 +2059,7 @@
         compositorTiming = getBE().mCompositorTiming;
     }
 
-    mDrawingState.traverseInZOrder([&](Layer* layer) {
+    mDrawingState.traverse([&](Layer* layer) {
         bool frameLatched = layer->onPostComposition(displayDevice, glCompositionDoneFenceTime,
                                                      presentFenceTime, compositorTiming);
         if (frameLatched) {
@@ -2496,7 +2496,7 @@
     const nsecs_t expectedPresentTime = mExpectedPresentTime.load();
 
     // Notify all layers of available frames
-    mCurrentState.traverseInZOrder([expectedPresentTime](Layer* layer) {
+    mCurrentState.traverse([expectedPresentTime](Layer* layer) {
         layer->notifyAvailableFrames(expectedPresentTime);
     });
 
@@ -2506,7 +2506,7 @@
      */
 
     if ((transactionFlags & eTraversalNeeded) || mTraversalNeededMainThread) {
-        mCurrentState.traverseInZOrder([&](Layer* layer) {
+        mCurrentState.traverse([&](Layer* layer) {
             uint32_t trFlags = layer->getTransactionFlags(eTransactionNeeded);
             if (!trFlags) return;
 
@@ -2553,7 +2553,7 @@
         sp<const DisplayDevice> hintDisplay;
         uint32_t currentlayerStack = 0;
         bool first = true;
-        mCurrentState.traverseInZOrder([&](Layer* layer) {
+        mCurrentState.traverse([&](Layer* layer) {
             // NOTE: we rely on the fact that layers are sorted by
             // layerStack first (so we don't have to traverse the list
             // of displays for every layer).
@@ -2781,7 +2781,7 @@
     // clear the "changed" flags in current state
     mCurrentState.colorMatrixChanged = false;
 
-    mDrawingState.traverseInZOrder([&](Layer* layer) {
+    mDrawingState.traverse([&](Layer* layer) {
         layer->commitChildList();
 
         // If the layer can be reached when traversing mDrawingState, then the layer is no
@@ -2792,7 +2792,7 @@
     });
 
     commitOffscreenLayers();
-    mDrawingState.traverseInZOrder([&](Layer* layer) { layer->updateMirrorInfo(); });
+    mDrawingState.traverse([&](Layer* layer) { layer->updateMirrorInfo(); });
 }
 
 void SurfaceFlinger::withTracingLock(std::function<void()> lockedOperation) {
@@ -2817,7 +2817,7 @@
 
 void SurfaceFlinger::commitOffscreenLayers() {
     for (Layer* offscreenLayer : mOffscreenLayers) {
-        offscreenLayer->traverseInZOrder(LayerVector::StateSet::Drawing, [](Layer* layer) {
+        offscreenLayer->traverse(LayerVector::StateSet::Drawing, [](Layer* layer) {
             uint32_t trFlags = layer->getTransactionFlags(eTransactionNeeded);
             if (!trFlags) return;
 
@@ -2858,7 +2858,7 @@
     // 3.) Layer 1 is latched.
     // Display is now waiting on Layer 1's frame, which is behind layer 0's
     // second frame. But layer 0's second frame could be waiting on display.
-    mDrawingState.traverseInZOrder([&](Layer* layer) {
+    mDrawingState.traverse([&](Layer* layer) {
         if (layer->hasReadyFrame()) {
             frameQueued = true;
             if (layer->shouldPresentNow(expectedPresentTime)) {
@@ -2876,7 +2876,7 @@
     // be shown on screen. Therefore, we need to latch and release buffers of offscreen
     // layers to ensure dequeueBuffer doesn't block indefinitely.
     for (Layer* offscreenLayer : mOffscreenLayers) {
-        offscreenLayer->traverseInZOrder(LayerVector::StateSet::Drawing,
+        offscreenLayer->traverse(LayerVector::StateSet::Drawing,
                                          [&](Layer* l) { l->latchAndReleaseBuffer(); });
     }
 
@@ -2911,7 +2911,7 @@
         mBootStage = BootStage::BOOTANIMATION;
     }
 
-    mDrawingState.traverseInZOrder([&](Layer* layer) { layer->updateCloneBufferInfo(); });
+    mDrawingState.traverse([&](Layer* layer) { layer->updateCloneBufferInfo(); });
 
     // Only continue with the refresh if there is actually new work to do
     return !mLayersWithQueuedFrames.empty() && newDataLatched;
@@ -3733,7 +3733,7 @@
     bool matchFound = true;
     while (matchFound) {
         matchFound = false;
-        mCurrentState.traverseInZOrder([&](Layer* layer) {
+        mCurrentState.traverse([&](Layer* layer) {
             if (layer->getName() == uniqueName) {
                 matchFound = true;
                 uniqueName = base::StringPrintf("%s#%u", name, ++dupeCounter);
@@ -4104,7 +4104,7 @@
     const bool clearAll = args.size() < 2;
     const auto name = clearAll ? String8() : String8(args[1]);
 
-    mCurrentState.traverseInZOrder([&](Layer* layer) {
+    mCurrentState.traverse([&](Layer* layer) {
         if (clearAll || layer->getName() == name.string()) {
             layer->clearFrameStats();
         }
@@ -4120,7 +4120,7 @@
 // This should only be called from the main thread.  Otherwise it would need
 // the lock and should use mCurrentState rather than mDrawingState.
 void SurfaceFlinger::logFrameStats() {
-    mDrawingState.traverseInZOrder([&](Layer* layer) {
+    mDrawingState.traverse([&](Layer* layer) {
         layer->logFrameStats();
     });
 
@@ -4355,7 +4355,7 @@
     result.append("Offscreen Layers:\n");
     postMessageSync(new LambdaMessage([&]() {
         for (Layer* offscreenLayer : mOffscreenLayers) {
-            offscreenLayer->traverseInZOrder(LayerVector::StateSet::Drawing, [&](Layer* layer) {
+            offscreenLayer->traverse(LayerVector::StateSet::Drawing, [&](Layer* layer) {
                 layer->dumpCallingUidPid(result);
             });
         }
@@ -5588,6 +5588,10 @@
 
 // ---------------------------------------------------------------------------
 
+void SurfaceFlinger::State::traverse(const LayerVector::Visitor& visitor) const {
+    layersSortedByZ.traverse(visitor);
+}
+
 void SurfaceFlinger::State::traverseInZOrder(const LayerVector::Visitor& visitor) const {
     layersSortedByZ.traverseInZOrder(stateSet, visitor);
 }
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index f8980a5..4c8775d 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -384,6 +384,7 @@
 
         renderengine::ShadowSettings globalShadowSettings;
 
+        void traverse(const LayerVector::Visitor& visitor) const;
         void traverseInZOrder(const LayerVector::Visitor& visitor) const;
         void traverseInReverseZOrder(const LayerVector::Visitor& visitor) const;
     };
diff --git a/services/surfaceflinger/TimeStats/TimeStats.cpp b/services/surfaceflinger/TimeStats/TimeStats.cpp
index 12c98da..130e99a 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.cpp
+++ b/services/surfaceflinger/TimeStats/TimeStats.cpp
@@ -40,13 +40,18 @@
 status_pull_atom_return_t TimeStats::pullAtomCallback(int32_t atom_tag,
                                                       pulled_stats_event_list* data, void* cookie) {
     impl::TimeStats* timeStats = reinterpret_cast<impl::TimeStats*>(cookie);
+    status_pull_atom_return_t result = STATS_PULL_SKIP;
     if (atom_tag == android::util::SURFACEFLINGER_STATS_GLOBAL_INFO) {
-        return timeStats->populateGlobalAtom(data);
+        result = timeStats->populateGlobalAtom(data);
     } else if (atom_tag == android::util::SURFACEFLINGER_STATS_LAYER_INFO) {
-        return timeStats->populateLayerAtom(data);
+        result = timeStats->populateLayerAtom(data);
     }
 
-    return STATS_PULL_SKIP;
+    // Enable timestats now. The first full pull for a given build is expected to
+    // have empty or very little stats, as stats are first enabled after the
+    // first pull is completed for either the global or layer stats.
+    timeStats->enable();
+    return result;
 }
 
 status_pull_atom_return_t TimeStats::populateGlobalAtom(pulled_stats_event_list* data) {
@@ -167,13 +172,19 @@
     }
 }
 
+TimeStats::~TimeStats() {
+    std::lock_guard<std::mutex> lock(mMutex);
+    mStatsDelegate->unregisterStatsPullAtomCallback(
+            android::util::SURFACEFLINGER_STATS_GLOBAL_INFO);
+    mStatsDelegate->unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO);
+}
+
 void TimeStats::onBootFinished() {
-    // Temporarily enable TimeStats by default. Telemetry is disabled while
-    // we move onto statsd, so TimeStats is currently not exercised at all
-    // during testing without enabling by default.
-    // TODO: remove this, as we should only be paying this overhead on devices
-    // where statsd exists.
-    enable();
+    std::lock_guard<std::mutex> lock(mMutex);
+    mStatsDelegate->registerStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO,
+                                                  TimeStats::pullAtomCallback, nullptr, this);
+    mStatsDelegate->registerStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO,
+                                                  TimeStats::pullAtomCallback, nullptr, this);
 }
 
 void TimeStats::parseArgs(bool asProto, const Vector<String16>& args, std::string& result) {
@@ -735,10 +746,6 @@
     mEnabled.store(true);
     mTimeStats.statsStart = static_cast<int64_t>(std::time(0));
     mPowerTime.prevTime = systemTime();
-    mStatsDelegate->registerStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO,
-                                                  TimeStats::pullAtomCallback, nullptr, this);
-    mStatsDelegate->registerStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO,
-                                                  TimeStats::pullAtomCallback, nullptr, this);
     ALOGD("Enabled");
 }
 
@@ -751,9 +758,6 @@
     flushPowerTimeLocked();
     mEnabled.store(false);
     mTimeStats.statsEnd = static_cast<int64_t>(std::time(0));
-    mStatsDelegate->unregisterStatsPullAtomCallback(
-            android::util::SURFACEFLINGER_STATS_GLOBAL_INFO);
-    mStatsDelegate->unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO);
     ALOGD("Disabled");
 }
 
diff --git a/services/surfaceflinger/TimeStats/TimeStats.h b/services/surfaceflinger/TimeStats/TimeStats.h
index 71f06af..67b9d10 100644
--- a/services/surfaceflinger/TimeStats/TimeStats.h
+++ b/services/surfaceflinger/TimeStats/TimeStats.h
@@ -182,6 +182,8 @@
               std::optional<size_t> maxPulledLayers,
               std::optional<size_t> maxPulledHistogramBuckets);
 
+    ~TimeStats() override;
+
     void onBootFinished() override;
     void parseArgs(bool asProto, const Vector<String16>& args, std::string& result) override;
     bool isEnabled() override;
diff --git a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
index 68e6697..f65af77 100644
--- a/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
+++ b/services/surfaceflinger/tests/unittests/TimeStatsTest.cpp
@@ -258,22 +258,25 @@
     ASSERT_FALSE(mTimeStats->isEnabled());
 }
 
-TEST_F(TimeStatsTest, enabledAfterBoot) {
+TEST_F(TimeStatsTest, registersCallbacksAfterBoot) {
     mTimeStats->onBootFinished();
-    ASSERT_TRUE(mTimeStats->isEnabled());
+    EXPECT_THAT(mDelegate->mAtomTags,
+                UnorderedElementsAre(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO,
+                                     android::util::SURFACEFLINGER_STATS_LAYER_INFO));
+}
+
+TEST_F(TimeStatsTest, unregistersCallbacksOnDestruction) {
+    EXPECT_CALL(*mDelegate,
+                unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO));
+    EXPECT_CALL(*mDelegate,
+                unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO));
+    mTimeStats.reset();
 }
 
 TEST_F(TimeStatsTest, canEnableAndDisableTimeStats) {
     EXPECT_TRUE(inputCommand(InputCommand::ENABLE, FMT_STRING).empty());
     ASSERT_TRUE(mTimeStats->isEnabled());
-    EXPECT_THAT(mDelegate->mAtomTags,
-                UnorderedElementsAre(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO,
-                                     android::util::SURFACEFLINGER_STATS_LAYER_INFO));
 
-    EXPECT_CALL(*mDelegate,
-                unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_GLOBAL_INFO));
-    EXPECT_CALL(*mDelegate,
-                unregisterStatsPullAtomCallback(android::util::SURFACEFLINGER_STATS_LAYER_INFO));
     EXPECT_TRUE(inputCommand(InputCommand::DISABLE, FMT_STRING).empty());
     ASSERT_FALSE(mTimeStats->isEnabled());
 }
diff --git a/services/surfaceflinger/tests/unittests/VSyncDispatchRealtimeTest.cpp b/services/surfaceflinger/tests/unittests/VSyncDispatchRealtimeTest.cpp
index acf852d..caac61d 100644
--- a/services/surfaceflinger/tests/unittests/VSyncDispatchRealtimeTest.cpp
+++ b/services/surfaceflinger/tests/unittests/VSyncDispatchRealtimeTest.cpp
@@ -37,7 +37,7 @@
 public:
     FixedRateIdealStubTracker() : mPeriod{toNs(3ms)} {}
 
-    void addVsyncTimestamp(nsecs_t) final {}
+    bool addVsyncTimestamp(nsecs_t) final { return true; }
 
     nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t timePoint) const final {
         auto const floor = timePoint % mPeriod;
@@ -60,7 +60,7 @@
 public:
     VRRStubTracker(nsecs_t period) : mPeriod{period} {}
 
-    void addVsyncTimestamp(nsecs_t) final {}
+    bool addVsyncTimestamp(nsecs_t) final { return true; }
 
     nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t time_point) const final {
         std::lock_guard<decltype(mMutex)> lk(mMutex);
diff --git a/services/surfaceflinger/tests/unittests/VSyncDispatchTimerQueueTest.cpp b/services/surfaceflinger/tests/unittests/VSyncDispatchTimerQueueTest.cpp
index 70c9225..3ab38e4 100644
--- a/services/surfaceflinger/tests/unittests/VSyncDispatchTimerQueueTest.cpp
+++ b/services/surfaceflinger/tests/unittests/VSyncDispatchTimerQueueTest.cpp
@@ -39,9 +39,10 @@
     MockVSyncTracker(nsecs_t period) : mPeriod{period} {
         ON_CALL(*this, nextAnticipatedVSyncTimeFrom(_))
                 .WillByDefault(Invoke(this, &MockVSyncTracker::nextVSyncTime));
+        ON_CALL(*this, addVsyncTimestamp(_)).WillByDefault(Return(true));
     }
 
-    MOCK_METHOD1(addVsyncTimestamp, void(nsecs_t));
+    MOCK_METHOD1(addVsyncTimestamp, bool(nsecs_t));
     MOCK_CONST_METHOD1(nextAnticipatedVSyncTimeFrom, nsecs_t(nsecs_t));
     MOCK_CONST_METHOD0(currentPeriod, nsecs_t());
     MOCK_METHOD1(setPeriod, void(nsecs_t));
diff --git a/services/surfaceflinger/tests/unittests/VSyncReactorTest.cpp b/services/surfaceflinger/tests/unittests/VSyncReactorTest.cpp
index ce1fafe..1de72b9 100644
--- a/services/surfaceflinger/tests/unittests/VSyncReactorTest.cpp
+++ b/services/surfaceflinger/tests/unittests/VSyncReactorTest.cpp
@@ -35,7 +35,8 @@
 
 class MockVSyncTracker : public VSyncTracker {
 public:
-    MOCK_METHOD1(addVsyncTimestamp, void(nsecs_t));
+    MockVSyncTracker() { ON_CALL(*this, addVsyncTimestamp(_)).WillByDefault(Return(true)); }
+    MOCK_METHOD1(addVsyncTimestamp, bool(nsecs_t));
     MOCK_CONST_METHOD1(nextAnticipatedVSyncTimeFrom, nsecs_t(nsecs_t));
     MOCK_CONST_METHOD0(currentPeriod, nsecs_t());
     MOCK_METHOD1(setPeriod, void(nsecs_t));
@@ -46,7 +47,9 @@
 public:
     VSyncTrackerWrapper(std::shared_ptr<VSyncTracker> const& tracker) : mTracker(tracker) {}
 
-    void addVsyncTimestamp(nsecs_t timestamp) final { mTracker->addVsyncTimestamp(timestamp); }
+    bool addVsyncTimestamp(nsecs_t timestamp) final {
+        return mTracker->addVsyncTimestamp(timestamp);
+    }
     nsecs_t nextAnticipatedVSyncTimeFrom(nsecs_t timePoint) const final {
         return mTracker->nextAnticipatedVSyncTimeFrom(timePoint);
     }
@@ -239,6 +242,22 @@
     EXPECT_FALSE(mReactor.addPresentFence(generateSignalledFenceWithTime(mDummyTime)));
 }
 
+TEST_F(VSyncReactorTest, ignoresProperlyAfterAPeriodConfirmation) {
+    bool periodFlushed = true;
+    EXPECT_CALL(*mMockTracker, addVsyncTimestamp(_)).Times(2);
+    mReactor.setIgnorePresentFences(true);
+
+    nsecs_t const newPeriod = 5000;
+    mReactor.setPeriod(newPeriod);
+
+    EXPECT_TRUE(mReactor.addResyncSample(0, &periodFlushed));
+    EXPECT_FALSE(periodFlushed);
+    EXPECT_FALSE(mReactor.addResyncSample(newPeriod, &periodFlushed));
+    EXPECT_TRUE(periodFlushed);
+
+    EXPECT_TRUE(mReactor.addPresentFence(generateSignalledFenceWithTime(0)));
+}
+
 TEST_F(VSyncReactorTest, queriesTrackerForNextRefreshNow) {
     nsecs_t const fakeTimestamp = 4839;
     EXPECT_CALL(*mMockTracker, currentPeriod()).Times(0);
@@ -330,6 +349,35 @@
     EXPECT_TRUE(periodFlushed);
 }
 
+TEST_F(VSyncReactorTest, reportedBadTimestampFromPredictorWillReactivateHwVSync) {
+    EXPECT_CALL(*mMockTracker, addVsyncTimestamp(_))
+            .WillOnce(Return(false))
+            .WillOnce(Return(true))
+            .WillOnce(Return(true));
+    EXPECT_TRUE(mReactor.addPresentFence(generateSignalledFenceWithTime(0)));
+    EXPECT_TRUE(mReactor.addPresentFence(generateSignalledFenceWithTime(0)));
+
+    nsecs_t skewyPeriod = period >> 1;
+    bool periodFlushed = false;
+    nsecs_t sampleTime = 0;
+    EXPECT_TRUE(mReactor.addResyncSample(sampleTime += skewyPeriod, &periodFlushed));
+    EXPECT_FALSE(periodFlushed);
+    EXPECT_FALSE(mReactor.addResyncSample(sampleTime += period, &periodFlushed));
+    EXPECT_FALSE(periodFlushed);
+}
+
+TEST_F(VSyncReactorTest, reportedBadTimestampFromPredictorWillReactivateHwVSyncPendingFence) {
+    EXPECT_CALL(*mMockTracker, addVsyncTimestamp(_))
+            .Times(2)
+            .WillOnce(Return(false))
+            .WillOnce(Return(true));
+
+    auto fence = generatePendingFence();
+    EXPECT_FALSE(mReactor.addPresentFence(fence));
+    signalFenceWithTime(fence, period >> 1);
+    EXPECT_TRUE(mReactor.addPresentFence(generateSignalledFenceWithTime(0)));
+}
+
 TEST_F(VSyncReactorTest, presentFenceAdditionDoesNotInterruptConfirmationProcess) {
     nsecs_t const newPeriod = 5000;
     mReactor.setPeriod(newPeriod);
diff --git a/vulkan/libvulkan/driver.cpp b/vulkan/libvulkan/driver.cpp
index 90a73e2..a7ec4ae 100644
--- a/vulkan/libvulkan/driver.cpp
+++ b/vulkan/libvulkan/driver.cpp
@@ -164,6 +164,11 @@
     "ro.board.platform",
 }};
 
+// LoadDriver returns:
+// * 0 when succeed, or
+// * -ENOENT when fail to open binary libraries, or
+// * -EINVAL when fail to find HAL_MODULE_INFO_SYM_AS_STR or
+//   HWVULKAN_HARDWARE_MODULE_ID in the library.
 int LoadDriver(android_namespace_t* library_namespace,
                const hwvulkan_module_t** module) {
     ATRACE_CALL();
@@ -221,7 +226,13 @@
         return -ENOENT;
     android::GraphicsEnv::getInstance().setDriverToLoad(
         android::GpuStatsInfo::Driver::VULKAN_UPDATED);
-    return LoadDriver(ns, module);
+    int result = LoadDriver(ns, module);
+    if (result != 0) {
+        LOG_ALWAYS_FATAL(
+            "couldn't find an updated Vulkan implementation from %s",
+            android::GraphicsEnv::getInstance().getDriverPath().c_str());
+    }
+    return result;
 }
 
 bool Hal::Open() {