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

 /*
  * Copyright 2019 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
 #define ATRACE_TAG ATRACE_TAG_GRAPHICS

 #include "RefreshRateConfigs.h"
 #include <android-base/stringprintf.h>
 #include <utils/Trace.h>
 #include <chrono>
 #include <cmath>

 namespace android::scheduler {

 using AllRefreshRatesMapType = RefreshRateConfigs::AllRefreshRatesMapType;
 using RefreshRate = RefreshRateConfigs::RefreshRate;

 const RefreshRate& RefreshRateConfigs::getRefreshRateForContent(
         const std::vector<LayerRequirement>& layers) const {
     std::lock_guard lock(mLock);
     int contentFramerate = 0;
     int explicitContentFramerate = 0;
     for (const auto& layer : layers) {
         const auto desiredRefreshRateRound = round<int>(layer.desiredRefreshRate);
         if (layer.vote == LayerVoteType::ExplicitDefault ||
             layer.vote == LayerVoteType::ExplicitExactOrMultiple) {
             if (desiredRefreshRateRound > explicitContentFramerate) {
                 explicitContentFramerate = desiredRefreshRateRound;
             }
         } else {
             if (desiredRefreshRateRound > contentFramerate) {
                 contentFramerate = desiredRefreshRateRound;
             }
         }
     }

     if (explicitContentFramerate != 0) {
         contentFramerate = explicitContentFramerate;
     } else if (contentFramerate == 0) {
         contentFramerate = round<int>(mMaxSupportedRefreshRate->fps);
     }
     ATRACE_INT("ContentFPS", contentFramerate);

     // Find the appropriate refresh rate with minimal error
     auto iter = min_element(mAvailableRefreshRates.cbegin(), mAvailableRefreshRates.cend(),
                             [contentFramerate](const auto& lhs, const auto& rhs) -> bool {
                                 return std::abs(lhs->fps - contentFramerate) <
                                         std::abs(rhs->fps - contentFramerate);
                             });

     // Some content aligns better on higher refresh rate. For example for 45fps we should choose
     // 90Hz config. However we should still prefer a lower refresh rate if the content doesn't
     // align well with both
     const RefreshRate* bestSoFar = *iter;
     constexpr float MARGIN = 0.05f;
     float ratio = (*iter)->fps / contentFramerate;
     if (std::abs(std::round(ratio) - ratio) > MARGIN) {
         while (iter != mAvailableRefreshRates.cend()) {
             ratio = (*iter)->fps / contentFramerate;

             if (std::abs(std::round(ratio) - ratio) <= MARGIN) {
                 bestSoFar = *iter;
                 break;
             }
             ++iter;
         }
     }

     return *bestSoFar;
 }

 std::pair<nsecs_t, nsecs_t> RefreshRateConfigs::getDisplayFrames(nsecs_t layerPeriod,
                                                                  nsecs_t displayPeriod) const {
     auto [displayFramesQuot, displayFramesRem] = std::div(layerPeriod, displayPeriod);
     if (displayFramesRem <= MARGIN_FOR_PERIOD_CALCULATION ||
         std::abs(displayFramesRem - displayPeriod) <= MARGIN_FOR_PERIOD_CALCULATION) {
         displayFramesQuot++;
         displayFramesRem = 0;
     }

     return {displayFramesQuot, displayFramesRem};
 }

 const RefreshRate& RefreshRateConfigs::getRefreshRateForContentV2(
         const std::vector<LayerRequirement>& layers, bool touchActive) const {
     ATRACE_CALL();
     ALOGV("getRefreshRateForContent %zu layers", layers.size());

     std::lock_guard lock(mLock);

     // For now if the touch is active return the peak refresh rate
     // This should be optimized to consider other layers as well.
     if (touchActive) {
         return *mAvailableRefreshRates.back();
     }

     int noVoteLayers = 0;
     int minVoteLayers = 0;
     int maxVoteLayers = 0;
     int explicitDefaultVoteLayers = 0;
     int explicitExactOrMultipleVoteLayers = 0;
     for (const auto& layer : layers) {
         if (layer.vote == LayerVoteType::NoVote)
             noVoteLayers++;
         else if (layer.vote == LayerVoteType::Min)
             minVoteLayers++;
         else if (layer.vote == LayerVoteType::Max)
             maxVoteLayers++;
         else if (layer.vote == LayerVoteType::ExplicitDefault)
             explicitDefaultVoteLayers++;
         else if (layer.vote == LayerVoteType::ExplicitExactOrMultiple)
             explicitExactOrMultipleVoteLayers++;
     }

     // Only if all layers want Min we should return Min
     if (noVoteLayers + minVoteLayers == layers.size()) {
         return *mAvailableRefreshRates.front();
     }

     // Find the best refresh rate based on score
     std::vector<std::pair<const RefreshRate*, float>> scores;
     scores.reserve(mAvailableRefreshRates.size());

     for (const auto refreshRate : mAvailableRefreshRates) {
         scores.emplace_back(refreshRate, 0.0f);
     }

     for (const auto& layer : layers) {
         ALOGV("Calculating score for %s (type: %d)", layer.name.c_str(), layer.vote);
         if (layer.vote == LayerVoteType::NoVote || layer.vote == LayerVoteType::Min) {
             continue;
         }

         auto weight = layer.weight;

         for (auto i = 0u; i < scores.size(); i++) {
             // If the layer wants Max, give higher score to the higher refresh rate
             if (layer.vote == LayerVoteType::Max) {
                 const auto ratio = scores[i].first->fps / scores.back().first->fps;
                 // use ratio^2 to get a lower score the more we get further from peak
                 const auto layerScore = ratio * ratio;
                 ALOGV("%s (Max, weight %.2f) gives %s score of %.2f", layer.name.c_str(), weight,
                       scores[i].first->name.c_str(), layerScore);
                 scores[i].second += weight * layerScore;
                 continue;
             }

             const auto displayPeriod = scores[i].first->vsyncPeriod;
             const auto layerPeriod = round<nsecs_t>(1e9f / layer.desiredRefreshRate);
             if (layer.vote == LayerVoteType::ExplicitDefault) {
                 const auto layerScore = [&]() {
                     const auto [displayFramesQuot, displayFramesRem] =
                             getDisplayFrames(layerPeriod, displayPeriod);
                     if (displayFramesQuot == 0) {
                         // Layer desired refresh rate is higher the display rate.
                         return static_cast<float>(layerPeriod) / static_cast<float>(displayPeriod);
                     }

                     return 1.0f -
                             (static_cast<float>(displayFramesRem) /
                              static_cast<float>(layerPeriod));
                 }();

                 ALOGV("%s (ExplicitDefault, weight %.2f) %.2fHz gives %s score of %.2f",
                       layer.name.c_str(), weight, 1e9f / layerPeriod, scores[i].first->name.c_str(),
                       layerScore);
                 scores[i].second += weight * layerScore;
                 continue;
             }

             if (layer.vote == LayerVoteType::ExplicitExactOrMultiple ||
                 layer.vote == LayerVoteType::Heuristic) {
                 const auto layerScore = [&]() {
                     // Calculate how many display vsyncs we need to present a single frame for this
                     // layer
                     const auto [displayFramesQuot, displayFramesRem] =
                             getDisplayFrames(layerPeriod, displayPeriod);
                     static constexpr size_t MAX_FRAMES_TO_FIT =
                             10; // Stop calculating when score < 0.1
                     if (displayFramesRem == 0) {
                         // Layer desired refresh rate matches the display rate.
                         return 1.0f;
                     }

                     if (displayFramesQuot == 0) {
                         // Layer desired refresh rate is higher the display rate.
                         return (static_cast<float>(layerPeriod) /
                                 static_cast<float>(displayPeriod)) *
                                 (1.0f / (MAX_FRAMES_TO_FIT + 1));
                     }

                     // Layer desired refresh rate is lower the display rate. Check how well it fits
                     // the cadence
                     auto diff = std::abs(displayFramesRem - (displayPeriod - displayFramesRem));
                     int iter = 2;
                     while (diff > MARGIN_FOR_PERIOD_CALCULATION && iter < MAX_FRAMES_TO_FIT) {
                         diff = diff - (displayPeriod - diff);
                         iter++;
                     }

                     return 1.0f / iter;
                 }();
                 ALOGV("%s (ExplicitExactOrMultiple, weight %.2f) %.2fHz gives %s score of %.2f",
                       layer.name.c_str(), weight, 1e9f / layerPeriod, scores[i].first->name.c_str(),
                       layerScore);
                 scores[i].second += weight * layerScore;
                 continue;
             }
         }
     }

     // Now that we scored all the refresh rates we need to pick the one that got the highest score.
     // In case of a tie we will pick the higher refresh rate if any of the layers wanted Max,
     // or the lower otherwise.
     const RefreshRate* bestRefreshRate = maxVoteLayers > 0
             ? getBestRefreshRate(scores.rbegin(), scores.rend())
             : getBestRefreshRate(scores.begin(), scores.end());

     return bestRefreshRate == nullptr ? *mCurrentRefreshRate : *bestRefreshRate;
 }

 template <typename Iter>
 const RefreshRate* RefreshRateConfigs::getBestRefreshRate(Iter begin, Iter end) const {
     const RefreshRate* bestRefreshRate = nullptr;
     float max = 0;
     for (auto i = begin; i != end; ++i) {
         const auto [refreshRate, score] = *i;
         ALOGV("%s scores %.2f", refreshRate->name.c_str(), score);

         ATRACE_INT(refreshRate->name.c_str(), round<int>(score * 100));

         if (score > max) {
             max = score;
             bestRefreshRate = refreshRate;
         }
     }

     return bestRefreshRate;
 }

 const AllRefreshRatesMapType& RefreshRateConfigs::getAllRefreshRates() const {
     return mRefreshRates;
 }

 const RefreshRate& RefreshRateConfigs::getMinRefreshRateByPolicy() const {
     std::lock_guard lock(mLock);
     return *mAvailableRefreshRates.front();
 }

 const RefreshRate& RefreshRateConfigs::getMaxRefreshRateByPolicy() const {
     std::lock_guard lock(mLock);
         return *mAvailableRefreshRates.back();
 }

 const RefreshRate& RefreshRateConfigs::getCurrentRefreshRate() const {
     std::lock_guard lock(mLock);
     return *mCurrentRefreshRate;
 }

 const RefreshRate& RefreshRateConfigs::getCurrentRefreshRateByPolicy() const {
     std::lock_guard lock(mLock);
     if (std::find(mAvailableRefreshRates.begin(), mAvailableRefreshRates.end(),
                   mCurrentRefreshRate) != mAvailableRefreshRates.end()) {
         return *mCurrentRefreshRate;
     }
     return mRefreshRates.at(mDefaultConfig);
 }

 void RefreshRateConfigs::setCurrentConfigId(HwcConfigIndexType configId) {
     std::lock_guard lock(mLock);
     mCurrentRefreshRate = &mRefreshRates.at(configId);
 }

 RefreshRateConfigs::RefreshRateConfigs(const std::vector<InputConfig>& configs,
                                        HwcConfigIndexType currentHwcConfig) {
     init(configs, currentHwcConfig);
 }

 RefreshRateConfigs::RefreshRateConfigs(
         const std::vector<std::shared_ptr<const HWC2::Display::Config>>& configs,
         HwcConfigIndexType currentConfigId) {
     std::vector<InputConfig> inputConfigs;
     for (size_t configId = 0; configId < configs.size(); ++configId) {
         auto configGroup = HwcConfigGroupType(configs[configId]->getConfigGroup());
         inputConfigs.push_back({HwcConfigIndexType(static_cast<int>(configId)), configGroup,
                                 configs[configId]->getVsyncPeriod()});
     }
     init(inputConfigs, currentConfigId);
 }

 status_t RefreshRateConfigs::setPolicy(HwcConfigIndexType defaultConfigId, float minRefreshRate,
                                        float maxRefreshRate, bool* outPolicyChanged) {
     std::lock_guard lock(mLock);
     bool policyChanged = defaultConfigId != mDefaultConfig ||
             minRefreshRate != mMinRefreshRateFps || maxRefreshRate != mMaxRefreshRateFps;
     if (outPolicyChanged) {
         *outPolicyChanged = policyChanged;
     }
     if (!policyChanged) {
         return NO_ERROR;
     }
     // defaultConfigId must be a valid config ID, and within the given refresh rate range.
     if (mRefreshRates.count(defaultConfigId) == 0) {
         return BAD_VALUE;
     }
     const RefreshRate& refreshRate = mRefreshRates.at(defaultConfigId);
     if (!refreshRate.inPolicy(minRefreshRate, maxRefreshRate)) {
         return BAD_VALUE;
     }
     mDefaultConfig = defaultConfigId;
     mMinRefreshRateFps = minRefreshRate;
     mMaxRefreshRateFps = maxRefreshRate;
     constructAvailableRefreshRates();
     return NO_ERROR;
 }

 void RefreshRateConfigs::getPolicy(HwcConfigIndexType* defaultConfigId, float* minRefreshRate,
                                    float* maxRefreshRate) const {
     std::lock_guard lock(mLock);
     *defaultConfigId = mDefaultConfig;
     *minRefreshRate = mMinRefreshRateFps;
     *maxRefreshRate = mMaxRefreshRateFps;
 }

 bool RefreshRateConfigs::isConfigAllowed(HwcConfigIndexType config) const {
     std::lock_guard lock(mLock);
     for (const RefreshRate* refreshRate : mAvailableRefreshRates) {
         if (refreshRate->configId == config) {
             return true;
         }
     }
     return false;
 }

 void RefreshRateConfigs::getSortedRefreshRateList(
         const std::function<bool(const RefreshRate&)>& shouldAddRefreshRate,
         std::vector<const RefreshRate*>* outRefreshRates) {
     outRefreshRates->clear();
     outRefreshRates->reserve(mRefreshRates.size());
     for (const auto& [type, refreshRate] : mRefreshRates) {
         if (shouldAddRefreshRate(refreshRate)) {
             ALOGV("getSortedRefreshRateList: config %d added to list policy",
                   refreshRate.configId.value());
             outRefreshRates->push_back(&refreshRate);
         }
     }

     std::sort(outRefreshRates->begin(), outRefreshRates->end(),
               [](const auto refreshRate1, const auto refreshRate2) {
                   return refreshRate1->vsyncPeriod > refreshRate2->vsyncPeriod;
               });
 }

 void RefreshRateConfigs::constructAvailableRefreshRates() {
     // Filter configs based on current policy and sort based on vsync period
     HwcConfigGroupType group = mRefreshRates.at(mDefaultConfig).configGroup;
     ALOGV("constructAvailableRefreshRates: default %d group %d min %.2f max %.2f",
           mDefaultConfig.value(), group.value(), mMinRefreshRateFps, mMaxRefreshRateFps);
     getSortedRefreshRateList(
             [&](const RefreshRate& refreshRate) REQUIRES(mLock) {
                 return refreshRate.configGroup == group &&
                         refreshRate.inPolicy(mMinRefreshRateFps, mMaxRefreshRateFps);
             },
             &mAvailableRefreshRates);

     std::string availableRefreshRates;
     for (const auto& refreshRate : mAvailableRefreshRates) {
         base::StringAppendF(&availableRefreshRates, "%s ", refreshRate->name.c_str());
     }

     ALOGV("Available refresh rates: %s", availableRefreshRates.c_str());
     LOG_ALWAYS_FATAL_IF(mAvailableRefreshRates.empty(),
                         "No compatible display configs for default=%d min=%.0f max=%.0f",
                         mDefaultConfig.value(), mMinRefreshRateFps, mMaxRefreshRateFps);
 }

 // NO_THREAD_SAFETY_ANALYSIS since this is called from the constructor
 void RefreshRateConfigs::init(const std::vector<InputConfig>& configs,
                               HwcConfigIndexType currentHwcConfig) NO_THREAD_SAFETY_ANALYSIS {
     LOG_ALWAYS_FATAL_IF(configs.empty());
     LOG_ALWAYS_FATAL_IF(currentHwcConfig.value() >= configs.size());

     auto buildRefreshRate = [&](InputConfig config) -> RefreshRate {
         const float fps = 1e9f / config.vsyncPeriod;
         return RefreshRate(config.configId, config.vsyncPeriod, config.configGroup,
                            base::StringPrintf("%2.ffps", fps), fps);
     };

     for (const auto& config : configs) {
         mRefreshRates.emplace(config.configId, buildRefreshRate(config));
         if (config.configId == currentHwcConfig) {
             mCurrentRefreshRate = &mRefreshRates.at(config.configId);
         }
     }

     std::vector<const RefreshRate*> sortedConfigs;
     getSortedRefreshRateList([](const RefreshRate&) { return true; }, &sortedConfigs);
     mDefaultConfig = currentHwcConfig;
     mMinSupportedRefreshRate = sortedConfigs.front();
     mMaxSupportedRefreshRate = sortedConfigs.back();
     constructAvailableRefreshRates();
 }

 } // namespace android::scheduler
	/*
	* Copyright 2019 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
	#define ATRACE_TAG ATRACE_TAG_GRAPHICS

	#include "RefreshRateConfigs.h"
	#include <android-base/stringprintf.h>
	#include <utils/Trace.h>
	#include <chrono>
	#include <cmath>

	namespace android::scheduler {

	using AllRefreshRatesMapType = RefreshRateConfigs::AllRefreshRatesMapType;
	using RefreshRate = RefreshRateConfigs::RefreshRate;

	const RefreshRate& RefreshRateConfigs::getRefreshRateForContent(
	const std::vector<LayerRequirement>& layers) const {
	std::lock_guard lock(mLock);
	int contentFramerate = 0;
	int explicitContentFramerate = 0;
	for (const auto& layer : layers) {
	const auto desiredRefreshRateRound = round<int>(layer.desiredRefreshRate);
	if (layer.vote == LayerVoteType::ExplicitDefault \|\|
	layer.vote == LayerVoteType::ExplicitExactOrMultiple) {
	if (desiredRefreshRateRound > explicitContentFramerate) {
	explicitContentFramerate = desiredRefreshRateRound;
	}
	} else {
	if (desiredRefreshRateRound > contentFramerate) {
	contentFramerate = desiredRefreshRateRound;
	}
	}
	}

	if (explicitContentFramerate != 0) {
	contentFramerate = explicitContentFramerate;
	} else if (contentFramerate == 0) {
	contentFramerate = round<int>(mMaxSupportedRefreshRate->fps);
	}
	ATRACE_INT("ContentFPS", contentFramerate);

	// Find the appropriate refresh rate with minimal error
	auto iter = min_element(mAvailableRefreshRates.cbegin(), mAvailableRefreshRates.cend(),
	[contentFramerate](const auto& lhs, const auto& rhs) -> bool {
	return std::abs(lhs->fps - contentFramerate) <
	std::abs(rhs->fps - contentFramerate);
	});

	// Some content aligns better on higher refresh rate. For example for 45fps we should choose
	// 90Hz config. However we should still prefer a lower refresh rate if the content doesn't
	// align well with both
	const RefreshRate* bestSoFar = *iter;
	constexpr float MARGIN = 0.05f;
	float ratio = (*iter)->fps / contentFramerate;
	if (std::abs(std::round(ratio) - ratio) > MARGIN) {
	while (iter != mAvailableRefreshRates.cend()) {
	ratio = (*iter)->fps / contentFramerate;

	if (std::abs(std::round(ratio) - ratio) <= MARGIN) {
	bestSoFar = *iter;
	break;
	}
	++iter;
	}
	}

	return *bestSoFar;
	}

	std::pair<nsecs_t, nsecs_t> RefreshRateConfigs::getDisplayFrames(nsecs_t layerPeriod,
	nsecs_t displayPeriod) const {
	auto [displayFramesQuot, displayFramesRem] = std::div(layerPeriod, displayPeriod);
	if (displayFramesRem <= MARGIN_FOR_PERIOD_CALCULATION \|\|
	std::abs(displayFramesRem - displayPeriod) <= MARGIN_FOR_PERIOD_CALCULATION) {
	displayFramesQuot++;
	displayFramesRem = 0;
	}

	return {displayFramesQuot, displayFramesRem};
	}

	const RefreshRate& RefreshRateConfigs::getRefreshRateForContentV2(
	const std::vector<LayerRequirement>& layers, bool touchActive) const {
	ATRACE_CALL();
	ALOGV("getRefreshRateForContent %zu layers", layers.size());

	std::lock_guard lock(mLock);

	// For now if the touch is active return the peak refresh rate
	// This should be optimized to consider other layers as well.
	if (touchActive) {
	return *mAvailableRefreshRates.back();
	}

	int noVoteLayers = 0;
	int minVoteLayers = 0;
	int maxVoteLayers = 0;
	int explicitDefaultVoteLayers = 0;
	int explicitExactOrMultipleVoteLayers = 0;
	for (const auto& layer : layers) {
	if (layer.vote == LayerVoteType::NoVote)
	noVoteLayers++;
	else if (layer.vote == LayerVoteType::Min)
	minVoteLayers++;
	else if (layer.vote == LayerVoteType::Max)
	maxVoteLayers++;
	else if (layer.vote == LayerVoteType::ExplicitDefault)
	explicitDefaultVoteLayers++;
	else if (layer.vote == LayerVoteType::ExplicitExactOrMultiple)
	explicitExactOrMultipleVoteLayers++;
	}

	// Only if all layers want Min we should return Min
	if (noVoteLayers + minVoteLayers == layers.size()) {
	return *mAvailableRefreshRates.front();
	}

	// Find the best refresh rate based on score
	std::vector<std::pair<const RefreshRate*, float>> scores;
	scores.reserve(mAvailableRefreshRates.size());

	for (const auto refreshRate : mAvailableRefreshRates) {
	scores.emplace_back(refreshRate, 0.0f);
	}

	for (const auto& layer : layers) {
	ALOGV("Calculating score for %s (type: %d)", layer.name.c_str(), layer.vote);
	if (layer.vote == LayerVoteType::NoVote \|\| layer.vote == LayerVoteType::Min) {
	continue;
	}

	auto weight = layer.weight;

	for (auto i = 0u; i < scores.size(); i++) {
	// If the layer wants Max, give higher score to the higher refresh rate
	if (layer.vote == LayerVoteType::Max) {
	const auto ratio = scores[i].first->fps / scores.back().first->fps;
	// use ratio^2 to get a lower score the more we get further from peak
	const auto layerScore = ratio * ratio;
	ALOGV("%s (Max, weight %.2f) gives %s score of %.2f", layer.name.c_str(), weight,
	scores[i].first->name.c_str(), layerScore);
	scores[i].second += weight * layerScore;
	continue;
	}

	const auto displayPeriod = scores[i].first->vsyncPeriod;
	const auto layerPeriod = round<nsecs_t>(1e9f / layer.desiredRefreshRate);
	if (layer.vote == LayerVoteType::ExplicitDefault) {
	const auto layerScore = [&]() {
	const auto [displayFramesQuot, displayFramesRem] =
	getDisplayFrames(layerPeriod, displayPeriod);
	if (displayFramesQuot == 0) {
	// Layer desired refresh rate is higher the display rate.
	return static_cast<float>(layerPeriod) / static_cast<float>(displayPeriod);
	}

	return 1.0f -
	(static_cast<float>(displayFramesRem) /
	static_cast<float>(layerPeriod));
	}();

	ALOGV("%s (ExplicitDefault, weight %.2f) %.2fHz gives %s score of %.2f",
	layer.name.c_str(), weight, 1e9f / layerPeriod, scores[i].first->name.c_str(),
	layerScore);
	scores[i].second += weight * layerScore;
	continue;
	}

	if (layer.vote == LayerVoteType::ExplicitExactOrMultiple \|\|
	layer.vote == LayerVoteType::Heuristic) {
	const auto layerScore = [&]() {
	// Calculate how many display vsyncs we need to present a single frame for this
	// layer
	const auto [displayFramesQuot, displayFramesRem] =
	getDisplayFrames(layerPeriod, displayPeriod);
	static constexpr size_t MAX_FRAMES_TO_FIT =
	10; // Stop calculating when score < 0.1
	if (displayFramesRem == 0) {
	// Layer desired refresh rate matches the display rate.
	return 1.0f;
	}

	if (displayFramesQuot == 0) {
	// Layer desired refresh rate is higher the display rate.
	return (static_cast<float>(layerPeriod) /
	static_cast<float>(displayPeriod)) *
	(1.0f / (MAX_FRAMES_TO_FIT + 1));
	}

	// Layer desired refresh rate is lower the display rate. Check how well it fits
	// the cadence
	auto diff = std::abs(displayFramesRem - (displayPeriod - displayFramesRem));
	int iter = 2;
	while (diff > MARGIN_FOR_PERIOD_CALCULATION && iter < MAX_FRAMES_TO_FIT) {
	diff = diff - (displayPeriod - diff);
	iter++;
	}

	return 1.0f / iter;
	}();
	ALOGV("%s (ExplicitExactOrMultiple, weight %.2f) %.2fHz gives %s score of %.2f",
	layer.name.c_str(), weight, 1e9f / layerPeriod, scores[i].first->name.c_str(),
	layerScore);
	scores[i].second += weight * layerScore;
	continue;
	}
	}
	}

	// Now that we scored all the refresh rates we need to pick the one that got the highest score.
	// In case of a tie we will pick the higher refresh rate if any of the layers wanted Max,
	// or the lower otherwise.
	const RefreshRate* bestRefreshRate = maxVoteLayers > 0
	? getBestRefreshRate(scores.rbegin(), scores.rend())
	: getBestRefreshRate(scores.begin(), scores.end());

	return bestRefreshRate == nullptr ? mCurrentRefreshRate : bestRefreshRate;
	}

	template <typename Iter>
	const RefreshRate* RefreshRateConfigs::getBestRefreshRate(Iter begin, Iter end) const {
	const RefreshRate* bestRefreshRate = nullptr;
	float max = 0;
	for (auto i = begin; i != end; ++i) {
	const auto [refreshRate, score] = *i;
	ALOGV("%s scores %.2f", refreshRate->name.c_str(), score);

	ATRACE_INT(refreshRate->name.c_str(), round<int>(score * 100));

	if (score > max) {
	max = score;
	bestRefreshRate = refreshRate;
	}
	}

	return bestRefreshRate;
	}

	const AllRefreshRatesMapType& RefreshRateConfigs::getAllRefreshRates() const {
	return mRefreshRates;
	}

	const RefreshRate& RefreshRateConfigs::getMinRefreshRateByPolicy() const {
	std::lock_guard lock(mLock);
	return *mAvailableRefreshRates.front();
	}

	const RefreshRate& RefreshRateConfigs::getMaxRefreshRateByPolicy() const {
	std::lock_guard lock(mLock);
	return *mAvailableRefreshRates.back();
	}

	const RefreshRate& RefreshRateConfigs::getCurrentRefreshRate() const {
	std::lock_guard lock(mLock);
	return *mCurrentRefreshRate;
	}

	const RefreshRate& RefreshRateConfigs::getCurrentRefreshRateByPolicy() const {
	std::lock_guard lock(mLock);
	if (std::find(mAvailableRefreshRates.begin(), mAvailableRefreshRates.end(),
	mCurrentRefreshRate) != mAvailableRefreshRates.end()) {
	return *mCurrentRefreshRate;
	}
	return mRefreshRates.at(mDefaultConfig);
	}

	void RefreshRateConfigs::setCurrentConfigId(HwcConfigIndexType configId) {
	std::lock_guard lock(mLock);
	mCurrentRefreshRate = &mRefreshRates.at(configId);
	}

	RefreshRateConfigs::RefreshRateConfigs(const std::vector<InputConfig>& configs,
	HwcConfigIndexType currentHwcConfig) {
	init(configs, currentHwcConfig);
	}

	RefreshRateConfigs::RefreshRateConfigs(
	const std::vector<std::shared_ptr<const HWC2::Display::Config>>& configs,
	HwcConfigIndexType currentConfigId) {
	std::vector<InputConfig> inputConfigs;
	for (size_t configId = 0; configId < configs.size(); ++configId) {
	auto configGroup = HwcConfigGroupType(configs[configId]->getConfigGroup());
	inputConfigs.push_back({HwcConfigIndexType(static_cast<int>(configId)), configGroup,
	configs[configId]->getVsyncPeriod()});
	}
	init(inputConfigs, currentConfigId);
	}

	status_t RefreshRateConfigs::setPolicy(HwcConfigIndexType defaultConfigId, float minRefreshRate,
	float maxRefreshRate, bool* outPolicyChanged) {
	std::lock_guard lock(mLock);
	bool policyChanged = defaultConfigId != mDefaultConfig \|\|
	minRefreshRate != mMinRefreshRateFps \|\| maxRefreshRate != mMaxRefreshRateFps;
	if (outPolicyChanged) {
	*outPolicyChanged = policyChanged;
	}
	if (!policyChanged) {
	return NO_ERROR;
	}
	// defaultConfigId must be a valid config ID, and within the given refresh rate range.
	if (mRefreshRates.count(defaultConfigId) == 0) {
	return BAD_VALUE;
	}
	const RefreshRate& refreshRate = mRefreshRates.at(defaultConfigId);
	if (!refreshRate.inPolicy(minRefreshRate, maxRefreshRate)) {
	return BAD_VALUE;
	}
	mDefaultConfig = defaultConfigId;
	mMinRefreshRateFps = minRefreshRate;
	mMaxRefreshRateFps = maxRefreshRate;
	constructAvailableRefreshRates();
	return NO_ERROR;
	}

	void RefreshRateConfigs::getPolicy(HwcConfigIndexType* defaultConfigId, float* minRefreshRate,
	float* maxRefreshRate) const {
	std::lock_guard lock(mLock);
	*defaultConfigId = mDefaultConfig;
	*minRefreshRate = mMinRefreshRateFps;
	*maxRefreshRate = mMaxRefreshRateFps;
	}

	bool RefreshRateConfigs::isConfigAllowed(HwcConfigIndexType config) const {
	std::lock_guard lock(mLock);
	for (const RefreshRate* refreshRate : mAvailableRefreshRates) {
	if (refreshRate->configId == config) {
	return true;
	}
	}
	return false;
	}

	void RefreshRateConfigs::getSortedRefreshRateList(
	const std::function<bool(const RefreshRate&)>& shouldAddRefreshRate,
	std::vector<const RefreshRate> outRefreshRates) {
	outRefreshRates->clear();
	outRefreshRates->reserve(mRefreshRates.size());
	for (const auto& [type, refreshRate] : mRefreshRates) {
	if (shouldAddRefreshRate(refreshRate)) {
	ALOGV("getSortedRefreshRateList: config %d added to list policy",
	refreshRate.configId.value());
	outRefreshRates->push_back(&refreshRate);
	}
	}

	std::sort(outRefreshRates->begin(), outRefreshRates->end(),
	[](const auto refreshRate1, const auto refreshRate2) {
	return refreshRate1->vsyncPeriod > refreshRate2->vsyncPeriod;
	});
	}

	void RefreshRateConfigs::constructAvailableRefreshRates() {
	// Filter configs based on current policy and sort based on vsync period
	HwcConfigGroupType group = mRefreshRates.at(mDefaultConfig).configGroup;
	ALOGV("constructAvailableRefreshRates: default %d group %d min %.2f max %.2f",
	mDefaultConfig.value(), group.value(), mMinRefreshRateFps, mMaxRefreshRateFps);
	getSortedRefreshRateList(
	[&](const RefreshRate& refreshRate) REQUIRES(mLock) {
	return refreshRate.configGroup == group &&
	refreshRate.inPolicy(mMinRefreshRateFps, mMaxRefreshRateFps);
	},
	&mAvailableRefreshRates);

	std::string availableRefreshRates;
	for (const auto& refreshRate : mAvailableRefreshRates) {
	base::StringAppendF(&availableRefreshRates, "%s ", refreshRate->name.c_str());
	}

	ALOGV("Available refresh rates: %s", availableRefreshRates.c_str());
	LOG_ALWAYS_FATAL_IF(mAvailableRefreshRates.empty(),
	"No compatible display configs for default=%d min=%.0f max=%.0f",
	mDefaultConfig.value(), mMinRefreshRateFps, mMaxRefreshRateFps);
	}

	// NO_THREAD_SAFETY_ANALYSIS since this is called from the constructor
	void RefreshRateConfigs::init(const std::vector<InputConfig>& configs,
	HwcConfigIndexType currentHwcConfig) NO_THREAD_SAFETY_ANALYSIS {
	LOG_ALWAYS_FATAL_IF(configs.empty());
	LOG_ALWAYS_FATAL_IF(currentHwcConfig.value() >= configs.size());

	auto buildRefreshRate = [&](InputConfig config) -> RefreshRate {
	const float fps = 1e9f / config.vsyncPeriod;
	return RefreshRate(config.configId, config.vsyncPeriod, config.configGroup,
	base::StringPrintf("%2.ffps", fps), fps);
	};

	for (const auto& config : configs) {
	mRefreshRates.emplace(config.configId, buildRefreshRate(config));
	if (config.configId == currentHwcConfig) {
	mCurrentRefreshRate = &mRefreshRates.at(config.configId);
	}
	}

	std::vector<const RefreshRate*> sortedConfigs;
	getSortedRefreshRateList([](const RefreshRate&) { return true; }, &sortedConfigs);
	mDefaultConfig = currentHwcConfig;
	mMinSupportedRefreshRate = sortedConfigs.front();
	mMaxSupportedRefreshRate = sortedConfigs.back();
	constructAvailableRefreshRates();
	}

	} // namespace android::scheduler