Move Choreographer to libgui.

For Attached Choreographer, we want to store, access, and set attributes
on a Choreographer from the SurfaceControl it is attached to.
SurfaceControl is in libgui, so move Choreographer from libnativedisplay
into libgui as well.

The Android.bp dep chain: libandroid includes< libhwui <
libnativedisplay < libgui

Bug: 255838011
Test: atest ChoreographerNativeTest (no regression)
Test: make and flash
Test: presubmit
Change-Id: Ie9f8cac93a888127ffa48d7061a467649e0ca694
diff --git a/libs/gui/Choreographer.cpp b/libs/gui/Choreographer.cpp
new file mode 100644
index 0000000..6b25b26
--- /dev/null
+++ b/libs/gui/Choreographer.cpp
@@ -0,0 +1,390 @@
+/*
+ * Copyright 2022 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.
+ */
+
+// #define LOG_NDEBUG 0
+
+#include <gui/Choreographer.h>
+#include <jni.h>
+
+#undef LOG_TAG
+#define LOG_TAG "AChoreographer"
+
+namespace {
+struct {
+    // Global JVM that is provided by zygote
+    JavaVM* jvm = nullptr;
+    struct {
+        jclass clazz;
+        jmethodID getInstance;
+        jmethodID registerNativeChoreographerForRefreshRateCallbacks;
+        jmethodID unregisterNativeChoreographerForRefreshRateCallbacks;
+    } displayManagerGlobal;
+} gJni;
+
+// Gets the JNIEnv* for this thread, and performs one-off initialization if we
+// have never retrieved a JNIEnv* pointer before.
+JNIEnv* getJniEnv() {
+    if (gJni.jvm == nullptr) {
+        ALOGW("AChoreographer: No JVM provided!");
+        return nullptr;
+    }
+
+    JNIEnv* env = nullptr;
+    if (gJni.jvm->GetEnv((void**)&env, JNI_VERSION_1_4) != JNI_OK) {
+        ALOGD("Attaching thread to JVM for AChoreographer");
+        JavaVMAttachArgs args = {JNI_VERSION_1_4, "AChoreographer_env", NULL};
+        jint attachResult = gJni.jvm->AttachCurrentThreadAsDaemon(&env, (void*)&args);
+        if (attachResult != JNI_OK) {
+            ALOGE("Unable to attach thread. Error: %d", attachResult);
+            return nullptr;
+        }
+    }
+    if (env == nullptr) {
+        ALOGW("AChoreographer: No JNI env available!");
+    }
+    return env;
+}
+
+inline const char* toString(bool value) {
+    return value ? "true" : "false";
+}
+} // namespace
+
+namespace android {
+
+Choreographer::Context Choreographer::gChoreographers;
+
+static thread_local Choreographer* gChoreographer;
+
+void Choreographer::initJVM(JNIEnv* env) {
+    env->GetJavaVM(&gJni.jvm);
+    // Now we need to find the java classes.
+    jclass dmgClass = env->FindClass("android/hardware/display/DisplayManagerGlobal");
+    gJni.displayManagerGlobal.clazz = static_cast<jclass>(env->NewGlobalRef(dmgClass));
+    gJni.displayManagerGlobal.getInstance =
+            env->GetStaticMethodID(dmgClass, "getInstance",
+                                   "()Landroid/hardware/display/DisplayManagerGlobal;");
+    gJni.displayManagerGlobal.registerNativeChoreographerForRefreshRateCallbacks =
+            env->GetMethodID(dmgClass, "registerNativeChoreographerForRefreshRateCallbacks", "()V");
+    gJni.displayManagerGlobal.unregisterNativeChoreographerForRefreshRateCallbacks =
+            env->GetMethodID(dmgClass, "unregisterNativeChoreographerForRefreshRateCallbacks",
+                             "()V");
+}
+
+Choreographer* Choreographer::getForThread() {
+    if (gChoreographer == nullptr) {
+        sp<Looper> looper = Looper::getForThread();
+        if (!looper.get()) {
+            ALOGW("No looper prepared for thread");
+            return nullptr;
+        }
+        gChoreographer = new Choreographer(looper);
+        status_t result = gChoreographer->initialize();
+        if (result != OK) {
+            ALOGW("Failed to initialize");
+            return nullptr;
+        }
+    }
+    return gChoreographer;
+}
+
+Choreographer::Choreographer(const sp<Looper>& looper)
+      : DisplayEventDispatcher(looper, gui::ISurfaceComposer::VsyncSource::eVsyncSourceApp),
+        mLooper(looper),
+        mThreadId(std::this_thread::get_id()) {
+    std::lock_guard<std::mutex> _l(gChoreographers.lock);
+    gChoreographers.ptrs.push_back(this);
+}
+
+Choreographer::~Choreographer() {
+    std::lock_guard<std::mutex> _l(gChoreographers.lock);
+    gChoreographers.ptrs.erase(std::remove_if(gChoreographers.ptrs.begin(),
+                                              gChoreographers.ptrs.end(),
+                                              [=](Choreographer* c) { return c == this; }),
+                               gChoreographers.ptrs.end());
+    // Only poke DisplayManagerGlobal to unregister if we previously registered
+    // callbacks.
+    if (gChoreographers.ptrs.empty() && gChoreographers.registeredToDisplayManager) {
+        gChoreographers.registeredToDisplayManager = false;
+        JNIEnv* env = getJniEnv();
+        if (env == nullptr) {
+            ALOGW("JNI environment is unavailable, skipping choreographer cleanup");
+            return;
+        }
+        jobject dmg = env->CallStaticObjectMethod(gJni.displayManagerGlobal.clazz,
+                                                  gJni.displayManagerGlobal.getInstance);
+        if (dmg == nullptr) {
+            ALOGW("DMS is not initialized yet, skipping choreographer cleanup");
+        } else {
+            env->CallVoidMethod(dmg,
+                                gJni.displayManagerGlobal
+                                        .unregisterNativeChoreographerForRefreshRateCallbacks);
+            env->DeleteLocalRef(dmg);
+        }
+    }
+}
+
+void Choreographer::postFrameCallbackDelayed(AChoreographer_frameCallback cb,
+                                             AChoreographer_frameCallback64 cb64,
+                                             AChoreographer_vsyncCallback vsyncCallback, void* data,
+                                             nsecs_t delay) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    FrameCallback callback{cb, cb64, vsyncCallback, data, now + delay};
+    {
+        std::lock_guard<std::mutex> _l{mLock};
+        mFrameCallbacks.push(callback);
+    }
+    if (callback.dueTime <= now) {
+        if (std::this_thread::get_id() != mThreadId) {
+            if (mLooper != nullptr) {
+                Message m{MSG_SCHEDULE_VSYNC};
+                mLooper->sendMessage(this, m);
+            } else {
+                scheduleVsync();
+            }
+        } else {
+            scheduleVsync();
+        }
+    } else {
+        if (mLooper != nullptr) {
+            Message m{MSG_SCHEDULE_CALLBACKS};
+            mLooper->sendMessageDelayed(delay, this, m);
+        } else {
+            scheduleCallbacks();
+        }
+    }
+}
+
+void Choreographer::registerRefreshRateCallback(AChoreographer_refreshRateCallback cb, void* data) {
+    std::lock_guard<std::mutex> _l{mLock};
+    for (const auto& callback : mRefreshRateCallbacks) {
+        // Don't re-add callbacks.
+        if (cb == callback.callback && data == callback.data) {
+            return;
+        }
+    }
+    mRefreshRateCallbacks.emplace_back(
+            RefreshRateCallback{.callback = cb, .data = data, .firstCallbackFired = false});
+    bool needsRegistration = false;
+    {
+        std::lock_guard<std::mutex> _l2(gChoreographers.lock);
+        needsRegistration = !gChoreographers.registeredToDisplayManager;
+    }
+    if (needsRegistration) {
+        JNIEnv* env = getJniEnv();
+        if (env == nullptr) {
+            ALOGW("JNI environment is unavailable, skipping registration");
+            return;
+        }
+        jobject dmg = env->CallStaticObjectMethod(gJni.displayManagerGlobal.clazz,
+                                                  gJni.displayManagerGlobal.getInstance);
+        if (dmg == nullptr) {
+            ALOGW("DMS is not initialized yet: skipping registration");
+            return;
+        } else {
+            env->CallVoidMethod(dmg,
+                                gJni.displayManagerGlobal
+                                        .registerNativeChoreographerForRefreshRateCallbacks,
+                                reinterpret_cast<int64_t>(this));
+            env->DeleteLocalRef(dmg);
+            {
+                std::lock_guard<std::mutex> _l2(gChoreographers.lock);
+                gChoreographers.registeredToDisplayManager = true;
+            }
+        }
+    } else {
+        scheduleLatestConfigRequest();
+    }
+}
+
+void Choreographer::unregisterRefreshRateCallback(AChoreographer_refreshRateCallback cb,
+                                                  void* data) {
+    std::lock_guard<std::mutex> _l{mLock};
+    mRefreshRateCallbacks.erase(std::remove_if(mRefreshRateCallbacks.begin(),
+                                               mRefreshRateCallbacks.end(),
+                                               [&](const RefreshRateCallback& callback) {
+                                                   return cb == callback.callback &&
+                                                           data == callback.data;
+                                               }),
+                                mRefreshRateCallbacks.end());
+}
+
+void Choreographer::scheduleLatestConfigRequest() {
+    if (mLooper != nullptr) {
+        Message m{MSG_HANDLE_REFRESH_RATE_UPDATES};
+        mLooper->sendMessage(this, m);
+    } else {
+        // If the looper thread is detached from Choreographer, then refresh rate
+        // changes will be handled in AChoreographer_handlePendingEvents, so we
+        // need to wake up the looper thread by writing to the write-end of the
+        // socket the looper is listening on.
+        // Fortunately, these events are small so sending packets across the
+        // socket should be atomic across processes.
+        DisplayEventReceiver::Event event;
+        event.header =
+                DisplayEventReceiver::Event::Header{DisplayEventReceiver::DISPLAY_EVENT_NULL,
+                                                    PhysicalDisplayId::fromPort(0), systemTime()};
+        injectEvent(event);
+    }
+}
+
+void Choreographer::scheduleCallbacks() {
+    const nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    nsecs_t dueTime;
+    {
+        std::lock_guard<std::mutex> _l{mLock};
+        // If there are no pending callbacks then don't schedule a vsync
+        if (mFrameCallbacks.empty()) {
+            return;
+        }
+        dueTime = mFrameCallbacks.top().dueTime;
+    }
+
+    if (dueTime <= now) {
+        ALOGV("choreographer %p ~ scheduling vsync", this);
+        scheduleVsync();
+        return;
+    }
+}
+
+void Choreographer::handleRefreshRateUpdates() {
+    std::vector<RefreshRateCallback> callbacks{};
+    const nsecs_t pendingPeriod = gChoreographers.mLastKnownVsync.load();
+    const nsecs_t lastPeriod = mLatestVsyncPeriod;
+    if (pendingPeriod > 0) {
+        mLatestVsyncPeriod = pendingPeriod;
+    }
+    {
+        std::lock_guard<std::mutex> _l{mLock};
+        for (auto& cb : mRefreshRateCallbacks) {
+            callbacks.push_back(cb);
+            cb.firstCallbackFired = true;
+        }
+    }
+
+    for (auto& cb : callbacks) {
+        if (!cb.firstCallbackFired || (pendingPeriod > 0 && pendingPeriod != lastPeriod)) {
+            cb.callback(pendingPeriod, cb.data);
+        }
+    }
+}
+
+void Choreographer::dispatchVsync(nsecs_t timestamp, PhysicalDisplayId, uint32_t,
+                                  VsyncEventData vsyncEventData) {
+    std::vector<FrameCallback> callbacks{};
+    {
+        std::lock_guard<std::mutex> _l{mLock};
+        nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+        while (!mFrameCallbacks.empty() && mFrameCallbacks.top().dueTime < now) {
+            callbacks.push_back(mFrameCallbacks.top());
+            mFrameCallbacks.pop();
+        }
+    }
+    mLastVsyncEventData = vsyncEventData;
+    for (const auto& cb : callbacks) {
+        if (cb.vsyncCallback != nullptr) {
+            const ChoreographerFrameCallbackDataImpl frameCallbackData =
+                    createFrameCallbackData(timestamp);
+            registerStartTime();
+            mInCallback = true;
+            cb.vsyncCallback(reinterpret_cast<const AChoreographerFrameCallbackData*>(
+                                     &frameCallbackData),
+                             cb.data);
+            mInCallback = false;
+        } else if (cb.callback64 != nullptr) {
+            cb.callback64(timestamp, cb.data);
+        } else if (cb.callback != nullptr) {
+            cb.callback(timestamp, cb.data);
+        }
+    }
+}
+
+void Choreographer::dispatchHotplug(nsecs_t, PhysicalDisplayId displayId, bool connected) {
+    ALOGV("choreographer %p ~ received hotplug event (displayId=%s, connected=%s), ignoring.", this,
+          to_string(displayId).c_str(), toString(connected));
+}
+
+void Choreographer::dispatchModeChanged(nsecs_t, PhysicalDisplayId, int32_t, nsecs_t) {
+    LOG_ALWAYS_FATAL("dispatchModeChanged was called but was never registered");
+}
+
+void Choreographer::dispatchFrameRateOverrides(nsecs_t, PhysicalDisplayId,
+                                               std::vector<FrameRateOverride>) {
+    LOG_ALWAYS_FATAL("dispatchFrameRateOverrides was called but was never registered");
+}
+
+void Choreographer::dispatchNullEvent(nsecs_t, PhysicalDisplayId) {
+    ALOGV("choreographer %p ~ received null event.", this);
+    handleRefreshRateUpdates();
+}
+
+void Choreographer::handleMessage(const Message& message) {
+    switch (message.what) {
+        case MSG_SCHEDULE_CALLBACKS:
+            scheduleCallbacks();
+            break;
+        case MSG_SCHEDULE_VSYNC:
+            scheduleVsync();
+            break;
+        case MSG_HANDLE_REFRESH_RATE_UPDATES:
+            handleRefreshRateUpdates();
+            break;
+    }
+}
+
+int64_t Choreographer::getFrameInterval() const {
+    return mLastVsyncEventData.frameInterval;
+}
+
+bool Choreographer::inCallback() const {
+    return mInCallback;
+}
+
+ChoreographerFrameCallbackDataImpl Choreographer::createFrameCallbackData(nsecs_t timestamp) const {
+    return {.frameTimeNanos = timestamp,
+            .vsyncEventData = mLastVsyncEventData,
+            .choreographer = this};
+}
+
+void Choreographer::registerStartTime() const {
+    std::scoped_lock _l(gChoreographers.lock);
+    for (VsyncEventData::FrameTimeline frameTimeline : mLastVsyncEventData.frameTimelines) {
+        while (gChoreographers.startTimes.size() >= kMaxStartTimes) {
+            gChoreographers.startTimes.erase(gChoreographers.startTimes.begin());
+        }
+        gChoreographers.startTimes[frameTimeline.vsyncId] = systemTime(SYSTEM_TIME_MONOTONIC);
+    }
+}
+
+void Choreographer::signalRefreshRateCallbacks(nsecs_t vsyncPeriod) {
+    std::lock_guard<std::mutex> _l(gChoreographers.lock);
+    gChoreographers.mLastKnownVsync.store(vsyncPeriod);
+    for (auto c : gChoreographers.ptrs) {
+        c->scheduleLatestConfigRequest();
+    }
+}
+
+int64_t Choreographer::getStartTimeNanosForVsyncId(AVsyncId vsyncId) {
+    std::scoped_lock _l(gChoreographers.lock);
+    const auto iter = gChoreographers.startTimes.find(vsyncId);
+    if (iter == gChoreographers.startTimes.end()) {
+        ALOGW("Start time was not found for vsync id: %" PRId64, vsyncId);
+        return 0;
+    }
+    return iter->second;
+}
+
+} // namespace android
\ No newline at end of file