services/surfaceflinger/Scheduler/Scheduler.cpp - platform/frameworks/native - Gitiles

 /*
  * Copyright 2018 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 ATRACE_TAG ATRACE_TAG_GRAPHICS

 #include "Scheduler.h"

 #include <algorithm>
 #include <cinttypes>
 #include <cstdint>
 #include <memory>
 #include <numeric>

 #include <android/hardware/configstore/1.0/ISurfaceFlingerConfigs.h>
 #include <android/hardware/configstore/1.1/ISurfaceFlingerConfigs.h>
 #include <android/hardware/configstore/1.2/ISurfaceFlingerConfigs.h>
 #include <configstore/Utils.h>
 #include <cutils/properties.h>
 #include <gui/ISurfaceComposer.h>
 #include <ui/DisplayStatInfo.h>
 #include <utils/Timers.h>
 #include <utils/Trace.h>

 #include "DispSync.h"
 #include "DispSyncSource.h"
 #include "EventControlThread.h"
 #include "EventThread.h"
 #include "IdleTimer.h"
 #include "InjectVSyncSource.h"
 #include "SchedulerUtils.h"
 #include "SurfaceFlingerProperties.h"

 namespace android {

 using namespace android::hardware::configstore;
 using namespace android::hardware::configstore::V1_0;
 using namespace android::sysprop;

 #define RETURN_VALUE_IF_INVALID(value) \
     if (handle == nullptr || mConnections.count(handle->id) == 0) return value
 #define RETURN_IF_INVALID() \
     if (handle == nullptr || mConnections.count(handle->id) == 0) return

 std::atomic<int64_t> Scheduler::sNextId = 0;

 Scheduler::Scheduler(impl::EventControlThread::SetVSyncEnabledFunction function)
       : mHasSyncFramework(running_without_sync_framework(true)),
         mDispSyncPresentTimeOffset(present_time_offset_from_vsync_ns(0)),
         mPrimaryHWVsyncEnabled(false),
         mHWVsyncAvailable(false) {
     // Note: We create a local temporary with the real DispSync implementation
     // type temporarily so we can initialize it with the configured values,
     // before storing it for more generic use using the interface type.
     auto primaryDispSync = std::make_unique<impl::DispSync>("SchedulerDispSync");
     primaryDispSync->init(mHasSyncFramework, mDispSyncPresentTimeOffset);
     mPrimaryDispSync = std::move(primaryDispSync);
     mEventControlThread = std::make_unique<impl::EventControlThread>(function);

     char value[PROPERTY_VALUE_MAX];
     property_get("debug.sf.set_idle_timer_ms", value, "0");
     mSetIdleTimerMs = atoi(value);

     if (mSetIdleTimerMs > 0) {
         mIdleTimer =
                 std::make_unique<scheduler::IdleTimer>(std::chrono::milliseconds(mSetIdleTimerMs),
                                                        [this] { expiredTimerCallback(); });
         mIdleTimer->start();
     }
 }

 Scheduler::~Scheduler() = default;

 sp<Scheduler::ConnectionHandle> Scheduler::createConnection(
         const char* connectionName, int64_t phaseOffsetNs, ResyncCallback resyncCallback,
         impl::EventThread::InterceptVSyncsCallback interceptCallback) {
     const int64_t id = sNextId++;
     ALOGV("Creating a connection handle with ID: %" PRId64 "\n", id);

     std::unique_ptr<EventThread> eventThread =
             makeEventThread(connectionName, mPrimaryDispSync.get(), phaseOffsetNs,
                             std::move(interceptCallback));
     auto connection = std::make_unique<Connection>(new ConnectionHandle(id),
                                                    eventThread->createEventConnection(
                                                            std::move(resyncCallback)),
                                                    std::move(eventThread));

     mConnections.insert(std::make_pair(id, std::move(connection)));
     return mConnections[id]->handle;
 }

 std::unique_ptr<EventThread> Scheduler::makeEventThread(
         const char* connectionName, DispSync* dispSync, int64_t phaseOffsetNs,
         impl::EventThread::InterceptVSyncsCallback interceptCallback) {
     std::unique_ptr<VSyncSource> eventThreadSource =
             std::make_unique<DispSyncSource>(dispSync, phaseOffsetNs, true, connectionName);
     return std::make_unique<impl::EventThread>(std::move(eventThreadSource),
                                                std::move(interceptCallback),
                                                [this] { resetIdleTimer(); }, connectionName);
 }

 sp<IDisplayEventConnection> Scheduler::createDisplayEventConnection(
         const sp<Scheduler::ConnectionHandle>& handle, ResyncCallback resyncCallback) {
     RETURN_VALUE_IF_INVALID(nullptr);
     return mConnections[handle->id]->thread->createEventConnection(std::move(resyncCallback));
 }

 EventThread* Scheduler::getEventThread(const sp<Scheduler::ConnectionHandle>& handle) {
     RETURN_VALUE_IF_INVALID(nullptr);
     return mConnections[handle->id]->thread.get();
 }

 sp<EventThreadConnection> Scheduler::getEventConnection(const sp<ConnectionHandle>& handle) {
     RETURN_VALUE_IF_INVALID(nullptr);
     return mConnections[handle->id]->eventConnection;
 }

 void Scheduler::hotplugReceived(const sp<Scheduler::ConnectionHandle>& handle,
                                 EventThread::DisplayType displayType, bool connected) {
     RETURN_IF_INVALID();
     mConnections[handle->id]->thread->onHotplugReceived(displayType, connected);
 }

 void Scheduler::onScreenAcquired(const sp<Scheduler::ConnectionHandle>& handle) {
     RETURN_IF_INVALID();
     mConnections[handle->id]->thread->onScreenAcquired();
 }

 void Scheduler::onScreenReleased(const sp<Scheduler::ConnectionHandle>& handle) {
     RETURN_IF_INVALID();
     mConnections[handle->id]->thread->onScreenReleased();
 }

 void Scheduler::dump(const sp<Scheduler::ConnectionHandle>& handle, std::string& result) const {
     RETURN_IF_INVALID();
     mConnections.at(handle->id)->thread->dump(result);
 }

 void Scheduler::setPhaseOffset(const sp<Scheduler::ConnectionHandle>& handle, nsecs_t phaseOffset) {
     RETURN_IF_INVALID();
     mConnections[handle->id]->thread->setPhaseOffset(phaseOffset);
 }

 void Scheduler::getDisplayStatInfo(DisplayStatInfo* stats) {
     stats->vsyncTime = mPrimaryDispSync->computeNextRefresh(0);
     stats->vsyncPeriod = mPrimaryDispSync->getPeriod();
 }

 void Scheduler::enableHardwareVsync() {
     std::lock_guard<std::mutex> lock(mHWVsyncLock);
     if (!mPrimaryHWVsyncEnabled && mHWVsyncAvailable) {
         mPrimaryDispSync->beginResync();
         mEventControlThread->setVsyncEnabled(true);
         mPrimaryHWVsyncEnabled = true;
     }
 }

 void Scheduler::disableHardwareVsync(bool makeUnavailable) {
     std::lock_guard<std::mutex> lock(mHWVsyncLock);
     if (mPrimaryHWVsyncEnabled) {
         mEventControlThread->setVsyncEnabled(false);
         mPrimaryDispSync->endResync();
         mPrimaryHWVsyncEnabled = false;
     }
     if (makeUnavailable) {
         mHWVsyncAvailable = false;
     }
 }

 void Scheduler::setVsyncPeriod(const nsecs_t period) {
     mPrimaryDispSync->reset();
     mPrimaryDispSync->setPeriod(period);
     enableHardwareVsync();
 }

 void Scheduler::addResyncSample(const nsecs_t timestamp) {
     bool needsHwVsync = false;
     { // Scope for the lock
         std::lock_guard<std::mutex> lock(mHWVsyncLock);
         if (mPrimaryHWVsyncEnabled) {
             needsHwVsync = mPrimaryDispSync->addResyncSample(timestamp);
         }
     }

     if (needsHwVsync) {
         enableHardwareVsync();
     } else {
         disableHardwareVsync(false);
     }
 }

 void Scheduler::addPresentFence(const std::shared_ptr<FenceTime>& fenceTime) {
     if (mPrimaryDispSync->addPresentFence(fenceTime)) {
         enableHardwareVsync();
     } else {
         disableHardwareVsync(false);
     }
 }

 void Scheduler::setIgnorePresentFences(bool ignore) {
     mPrimaryDispSync->setIgnorePresentFences(ignore);
 }

 void Scheduler::makeHWSyncAvailable(bool makeAvailable) {
     std::lock_guard<std::mutex> lock(mHWVsyncLock);
     mHWVsyncAvailable = makeAvailable;
 }

 void Scheduler::addFramePresentTimeForLayer(const nsecs_t framePresentTime, bool isAutoTimestamp,
                                             const std::string layerName) {
     // This is V1 logic. It calculates the average FPS based on the timestamp frequency
     // regardless of which layer the timestamp came from.
     // For now, the averages and FPS are recorded in the systrace.
     determineTimestampAverage(isAutoTimestamp, framePresentTime);

     // This is V2 logic. It calculates the average and median timestamp difference based on the
     // individual layer history. The results are recorded in the systrace.
     determineLayerTimestampStats(layerName, framePresentTime);
 }

 void Scheduler::incrementFrameCounter() {
     mLayerHistory.incrementCounter();
 }

 void Scheduler::setExpiredIdleTimerCallback(const ExpiredIdleTimerCallback& expiredTimerCallback) {
     std::lock_guard<std::mutex> lock(mCallbackLock);
     mExpiredTimerCallback = expiredTimerCallback;
 }

 void Scheduler::setResetIdleTimerCallback(const ResetIdleTimerCallback& resetTimerCallback) {
     std::lock_guard<std::mutex> lock(mCallbackLock);
     mResetTimerCallback = resetTimerCallback;
 }

 void Scheduler::updateFrameSkipping(const int64_t skipCount) {
     ATRACE_INT("FrameSkipCount", skipCount);
     if (mSkipCount != skipCount) {
         // Only update DispSync if it hasn't been updated yet.
         mPrimaryDispSync->setRefreshSkipCount(skipCount);
         mSkipCount = skipCount;
     }
 }

 void Scheduler::determineLayerTimestampStats(const std::string layerName,
                                              const nsecs_t framePresentTime) {
     mLayerHistory.insert(layerName, framePresentTime);
     std::vector<int64_t> differencesMs;

     // Traverse through the layer history, and determine the differences in present times.
     nsecs_t newestPresentTime = framePresentTime;
     std::string differencesText = "";
     for (int i = 1; i < mLayerHistory.getSize(); i++) {
         std::unordered_map<std::string, nsecs_t> layers = mLayerHistory.get(i);
         for (auto layer : layers) {
             if (layer.first != layerName) {
                 continue;
             }
             int64_t differenceMs = (newestPresentTime - layer.second) / 1000000;
             // Dismiss noise.
             if (differenceMs > 10 && differenceMs < 60) {
                 differencesMs.push_back(differenceMs);
             }
             IF_ALOGV() { differencesText += (std::to_string(differenceMs) + " "); }
             newestPresentTime = layer.second;
         }
     }
     ALOGV("Layer %s timestamp intervals: %s", layerName.c_str(), differencesText.c_str());

     if (!differencesMs.empty()) {
         // Mean/Average is a good indicator for when 24fps videos are playing, because the frames
         // come in 33, and 49 ms intervals with occasional 41ms.
         const int64_t meanMs = scheduler::calculate_mean(differencesMs);
         const auto tagMean = "TimestampMean_" + layerName;
         ATRACE_INT(tagMean.c_str(), meanMs);

         // Mode and median are good indicators for 30 and 60 fps videos, because the majority of
         // frames come in 16, or 33 ms intervals.
         const auto tagMedian = "TimestampMedian_" + layerName;
         ATRACE_INT(tagMedian.c_str(), scheduler::calculate_median(&differencesMs));

         const auto tagMode = "TimestampMode_" + layerName;
         ATRACE_INT(tagMode.c_str(), scheduler::calculate_mode(differencesMs));
     }
 }

 void Scheduler::determineTimestampAverage(bool isAutoTimestamp, const nsecs_t framePresentTime) {
     ATRACE_INT("AutoTimestamp", isAutoTimestamp);

     // Video does not have timestamp automatically set, so we discard timestamps that are
     // coming in from other sources for now.
     if (isAutoTimestamp) {
         return;
     }
     int64_t differenceMs = (framePresentTime - mPreviousFrameTimestamp) / 1000000;
     mPreviousFrameTimestamp = framePresentTime;

     if (differenceMs < 10 || differenceMs > 100) {
         // Dismiss noise.
         return;
     }
     ATRACE_INT("TimestampDiff", differenceMs);

     mTimeDifferences[mCounter % scheduler::ARRAY_SIZE] = differenceMs;
     mCounter++;
     int64_t mean = scheduler::calculate_mean(mTimeDifferences);
     ATRACE_INT("AutoTimestampMean", mean);

     // TODO(b/113612090): This are current numbers from trial and error while running videos
     // from YouTube at 24, 30, and 60 fps.
     if (mean > 14 && mean < 18) {
         ATRACE_INT("MediaFPS", 60);
     } else if (mean > 31 && mean < 34) {
         ATRACE_INT("MediaFPS", 30);
         return;
     } else if (mean > 39 && mean < 42) {
         ATRACE_INT("MediaFPS", 24);
     }
 }

 void Scheduler::resetIdleTimer() {
     if (mIdleTimer) {
         mIdleTimer->reset();
         ATRACE_INT("ExpiredIdleTimer", 0);
     }

     std::lock_guard<std::mutex> lock(mCallbackLock);
     if (mResetTimerCallback) {
         mResetTimerCallback();
     }
 }

 void Scheduler::expiredTimerCallback() {
     std::lock_guard<std::mutex> lock(mCallbackLock);
     if (mExpiredTimerCallback) {
         mExpiredTimerCallback();
         ATRACE_INT("ExpiredIdleTimer", 1);
     }
 }

 std::string Scheduler::doDump() {
     std::ostringstream stream;
     stream << "+  Idle timer interval: " << mSetIdleTimerMs << " ms" << std::endl;
     return stream.str();
 }

 } // namespace android
	/*
	* Copyright 2018 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 ATRACE_TAG ATRACE_TAG_GRAPHICS

	#include "Scheduler.h"

	#include <algorithm>
	#include <cinttypes>
	#include <cstdint>
	#include <memory>
	#include <numeric>

	#include <android/hardware/configstore/1.0/ISurfaceFlingerConfigs.h>
	#include <android/hardware/configstore/1.1/ISurfaceFlingerConfigs.h>
	#include <android/hardware/configstore/1.2/ISurfaceFlingerConfigs.h>
	#include <configstore/Utils.h>
	#include <cutils/properties.h>
	#include <gui/ISurfaceComposer.h>
	#include <ui/DisplayStatInfo.h>
	#include <utils/Timers.h>
	#include <utils/Trace.h>

	#include "DispSync.h"
	#include "DispSyncSource.h"
	#include "EventControlThread.h"
	#include "EventThread.h"
	#include "IdleTimer.h"
	#include "InjectVSyncSource.h"
	#include "SchedulerUtils.h"
	#include "SurfaceFlingerProperties.h"

	namespace android {

	using namespace android::hardware::configstore;
	using namespace android::hardware::configstore::V1_0;
	using namespace android::sysprop;

	#define RETURN_VALUE_IF_INVALID(value) \
	if (handle == nullptr \|\| mConnections.count(handle->id) == 0) return value
	#define RETURN_IF_INVALID() \
	if (handle == nullptr \|\| mConnections.count(handle->id) == 0) return

	std::atomic<int64_t> Scheduler::sNextId = 0;

	Scheduler::Scheduler(impl::EventControlThread::SetVSyncEnabledFunction function)
	: mHasSyncFramework(running_without_sync_framework(true)),
	mDispSyncPresentTimeOffset(present_time_offset_from_vsync_ns(0)),
	mPrimaryHWVsyncEnabled(false),
	mHWVsyncAvailable(false) {
	// Note: We create a local temporary with the real DispSync implementation
	// type temporarily so we can initialize it with the configured values,
	// before storing it for more generic use using the interface type.
	auto primaryDispSync = std::make_unique<impl::DispSync>("SchedulerDispSync");
	primaryDispSync->init(mHasSyncFramework, mDispSyncPresentTimeOffset);
	mPrimaryDispSync = std::move(primaryDispSync);
	mEventControlThread = std::make_unique<impl::EventControlThread>(function);

	char value[PROPERTY_VALUE_MAX];
	property_get("debug.sf.set_idle_timer_ms", value, "0");
	mSetIdleTimerMs = atoi(value);

	if (mSetIdleTimerMs > 0) {
	mIdleTimer =
	std::make_unique<scheduler::IdleTimer>(std::chrono::milliseconds(mSetIdleTimerMs),
	[this] { expiredTimerCallback(); });
	mIdleTimer->start();
	}
	}

	Scheduler::~Scheduler() = default;

	sp<Scheduler::ConnectionHandle> Scheduler::createConnection(
	const char* connectionName, int64_t phaseOffsetNs, ResyncCallback resyncCallback,
	impl::EventThread::InterceptVSyncsCallback interceptCallback) {
	const int64_t id = sNextId++;
	ALOGV("Creating a connection handle with ID: %" PRId64 "\n", id);

	std::unique_ptr<EventThread> eventThread =
	makeEventThread(connectionName, mPrimaryDispSync.get(), phaseOffsetNs,
	std::move(interceptCallback));
	auto connection = std::make_unique<Connection>(new ConnectionHandle(id),
	eventThread->createEventConnection(
	std::move(resyncCallback)),
	std::move(eventThread));

	mConnections.insert(std::make_pair(id, std::move(connection)));
	return mConnections[id]->handle;
	}

	std::unique_ptr<EventThread> Scheduler::makeEventThread(
	const char* connectionName, DispSync* dispSync, int64_t phaseOffsetNs,
	impl::EventThread::InterceptVSyncsCallback interceptCallback) {
	std::unique_ptr<VSyncSource> eventThreadSource =
	std::make_unique<DispSyncSource>(dispSync, phaseOffsetNs, true, connectionName);
	return std::make_unique<impl::EventThread>(std::move(eventThreadSource),
	std::move(interceptCallback),
	[this] { resetIdleTimer(); }, connectionName);
	}

	sp<IDisplayEventConnection> Scheduler::createDisplayEventConnection(
	const sp<Scheduler::ConnectionHandle>& handle, ResyncCallback resyncCallback) {
	RETURN_VALUE_IF_INVALID(nullptr);
	return mConnections[handle->id]->thread->createEventConnection(std::move(resyncCallback));
	}

	EventThread* Scheduler::getEventThread(const sp<Scheduler::ConnectionHandle>& handle) {
	RETURN_VALUE_IF_INVALID(nullptr);
	return mConnections[handle->id]->thread.get();
	}

	sp<EventThreadConnection> Scheduler::getEventConnection(const sp<ConnectionHandle>& handle) {
	RETURN_VALUE_IF_INVALID(nullptr);
	return mConnections[handle->id]->eventConnection;
	}

	void Scheduler::hotplugReceived(const sp<Scheduler::ConnectionHandle>& handle,
	EventThread::DisplayType displayType, bool connected) {
	RETURN_IF_INVALID();
	mConnections[handle->id]->thread->onHotplugReceived(displayType, connected);
	}

	void Scheduler::onScreenAcquired(const sp<Scheduler::ConnectionHandle>& handle) {
	RETURN_IF_INVALID();
	mConnections[handle->id]->thread->onScreenAcquired();
	}

	void Scheduler::onScreenReleased(const sp<Scheduler::ConnectionHandle>& handle) {
	RETURN_IF_INVALID();
	mConnections[handle->id]->thread->onScreenReleased();
	}

	void Scheduler::dump(const sp<Scheduler::ConnectionHandle>& handle, std::string& result) const {
	RETURN_IF_INVALID();
	mConnections.at(handle->id)->thread->dump(result);
	}

	void Scheduler::setPhaseOffset(const sp<Scheduler::ConnectionHandle>& handle, nsecs_t phaseOffset) {
	RETURN_IF_INVALID();
	mConnections[handle->id]->thread->setPhaseOffset(phaseOffset);
	}

	void Scheduler::getDisplayStatInfo(DisplayStatInfo* stats) {
	stats->vsyncTime = mPrimaryDispSync->computeNextRefresh(0);
	stats->vsyncPeriod = mPrimaryDispSync->getPeriod();
	}

	void Scheduler::enableHardwareVsync() {
	std::lock_guard<std::mutex> lock(mHWVsyncLock);
	if (!mPrimaryHWVsyncEnabled && mHWVsyncAvailable) {
	mPrimaryDispSync->beginResync();
	mEventControlThread->setVsyncEnabled(true);
	mPrimaryHWVsyncEnabled = true;
	}
	}

	void Scheduler::disableHardwareVsync(bool makeUnavailable) {
	std::lock_guard<std::mutex> lock(mHWVsyncLock);
	if (mPrimaryHWVsyncEnabled) {
	mEventControlThread->setVsyncEnabled(false);
	mPrimaryDispSync->endResync();
	mPrimaryHWVsyncEnabled = false;
	}
	if (makeUnavailable) {
	mHWVsyncAvailable = false;
	}
	}

	void Scheduler::setVsyncPeriod(const nsecs_t period) {
	mPrimaryDispSync->reset();
	mPrimaryDispSync->setPeriod(period);
	enableHardwareVsync();
	}

	void Scheduler::addResyncSample(const nsecs_t timestamp) {
	bool needsHwVsync = false;
	{ // Scope for the lock
	std::lock_guard<std::mutex> lock(mHWVsyncLock);
	if (mPrimaryHWVsyncEnabled) {
	needsHwVsync = mPrimaryDispSync->addResyncSample(timestamp);
	}
	}

	if (needsHwVsync) {
	enableHardwareVsync();
	} else {
	disableHardwareVsync(false);
	}
	}

	void Scheduler::addPresentFence(const std::shared_ptr<FenceTime>& fenceTime) {
	if (mPrimaryDispSync->addPresentFence(fenceTime)) {
	enableHardwareVsync();
	} else {
	disableHardwareVsync(false);
	}
	}

	void Scheduler::setIgnorePresentFences(bool ignore) {
	mPrimaryDispSync->setIgnorePresentFences(ignore);
	}

	void Scheduler::makeHWSyncAvailable(bool makeAvailable) {
	std::lock_guard<std::mutex> lock(mHWVsyncLock);
	mHWVsyncAvailable = makeAvailable;
	}

	void Scheduler::addFramePresentTimeForLayer(const nsecs_t framePresentTime, bool isAutoTimestamp,
	const std::string layerName) {
	// This is V1 logic. It calculates the average FPS based on the timestamp frequency
	// regardless of which layer the timestamp came from.
	// For now, the averages and FPS are recorded in the systrace.
	determineTimestampAverage(isAutoTimestamp, framePresentTime);

	// This is V2 logic. It calculates the average and median timestamp difference based on the
	// individual layer history. The results are recorded in the systrace.
	determineLayerTimestampStats(layerName, framePresentTime);
	}

	void Scheduler::incrementFrameCounter() {
	mLayerHistory.incrementCounter();
	}

	void Scheduler::setExpiredIdleTimerCallback(const ExpiredIdleTimerCallback& expiredTimerCallback) {
	std::lock_guard<std::mutex> lock(mCallbackLock);
	mExpiredTimerCallback = expiredTimerCallback;
	}

	void Scheduler::setResetIdleTimerCallback(const ResetIdleTimerCallback& resetTimerCallback) {
	std::lock_guard<std::mutex> lock(mCallbackLock);
	mResetTimerCallback = resetTimerCallback;
	}

	void Scheduler::updateFrameSkipping(const int64_t skipCount) {
	ATRACE_INT("FrameSkipCount", skipCount);
	if (mSkipCount != skipCount) {
	// Only update DispSync if it hasn't been updated yet.
	mPrimaryDispSync->setRefreshSkipCount(skipCount);
	mSkipCount = skipCount;
	}
	}

	void Scheduler::determineLayerTimestampStats(const std::string layerName,
	const nsecs_t framePresentTime) {
	mLayerHistory.insert(layerName, framePresentTime);
	std::vector<int64_t> differencesMs;

	// Traverse through the layer history, and determine the differences in present times.
	nsecs_t newestPresentTime = framePresentTime;
	std::string differencesText = "";
	for (int i = 1; i < mLayerHistory.getSize(); i++) {
	std::unordered_map<std::string, nsecs_t> layers = mLayerHistory.get(i);
	for (auto layer : layers) {
	if (layer.first != layerName) {
	continue;
	}
	int64_t differenceMs = (newestPresentTime - layer.second) / 1000000;
	// Dismiss noise.
	if (differenceMs > 10 && differenceMs < 60) {
	differencesMs.push_back(differenceMs);
	}
	IF_ALOGV() { differencesText += (std::to_string(differenceMs) + " "); }
	newestPresentTime = layer.second;
	}
	}
	ALOGV("Layer %s timestamp intervals: %s", layerName.c_str(), differencesText.c_str());

	if (!differencesMs.empty()) {
	// Mean/Average is a good indicator for when 24fps videos are playing, because the frames
	// come in 33, and 49 ms intervals with occasional 41ms.
	const int64_t meanMs = scheduler::calculate_mean(differencesMs);
	const auto tagMean = "TimestampMean_" + layerName;
	ATRACE_INT(tagMean.c_str(), meanMs);

	// Mode and median are good indicators for 30 and 60 fps videos, because the majority of
	// frames come in 16, or 33 ms intervals.
	const auto tagMedian = "TimestampMedian_" + layerName;
	ATRACE_INT(tagMedian.c_str(), scheduler::calculate_median(&differencesMs));

	const auto tagMode = "TimestampMode_" + layerName;
	ATRACE_INT(tagMode.c_str(), scheduler::calculate_mode(differencesMs));
	}
	}

	void Scheduler::determineTimestampAverage(bool isAutoTimestamp, const nsecs_t framePresentTime) {
	ATRACE_INT("AutoTimestamp", isAutoTimestamp);

	// Video does not have timestamp automatically set, so we discard timestamps that are
	// coming in from other sources for now.
	if (isAutoTimestamp) {
	return;
	}
	int64_t differenceMs = (framePresentTime - mPreviousFrameTimestamp) / 1000000;
	mPreviousFrameTimestamp = framePresentTime;

	if (differenceMs < 10 \|\| differenceMs > 100) {
	// Dismiss noise.
	return;
	}
	ATRACE_INT("TimestampDiff", differenceMs);

	mTimeDifferences[mCounter % scheduler::ARRAY_SIZE] = differenceMs;
	mCounter++;
	int64_t mean = scheduler::calculate_mean(mTimeDifferences);
	ATRACE_INT("AutoTimestampMean", mean);

	// TODO(b/113612090): This are current numbers from trial and error while running videos
	// from YouTube at 24, 30, and 60 fps.
	if (mean > 14 && mean < 18) {
	ATRACE_INT("MediaFPS", 60);
	} else if (mean > 31 && mean < 34) {
	ATRACE_INT("MediaFPS", 30);
	return;
	} else if (mean > 39 && mean < 42) {
	ATRACE_INT("MediaFPS", 24);
	}
	}

	void Scheduler::resetIdleTimer() {
	if (mIdleTimer) {
	mIdleTimer->reset();
	ATRACE_INT("ExpiredIdleTimer", 0);
	}

	std::lock_guard<std::mutex> lock(mCallbackLock);
	if (mResetTimerCallback) {
	mResetTimerCallback();
	}
	}

	void Scheduler::expiredTimerCallback() {
	std::lock_guard<std::mutex> lock(mCallbackLock);
	if (mExpiredTimerCallback) {
	mExpiredTimerCallback();
	ATRACE_INT("ExpiredIdleTimer", 1);
	}
	}

	std::string Scheduler::doDump() {
	std::ostringstream stream;
	stream << "+ Idle timer interval: " << mSetIdleTimerMs << " ms" << std::endl;
	return stream.str();
	}

	} // namespace android