SF: Add Planner predictor
Adds the Planner predictor, which tries to anticipate the composition
strategy that the Composer HAL is going to select based on the layer
geometry and historical composition strategies.
Bug: 158790260
Test: atest libcompositionengine_test libsurfaceflinger_unittest
Change-Id: Icd93e6f8c7437d99108610ac87d649568d13aa77
diff --git a/services/surfaceflinger/CompositionEngine/Android.bp b/services/surfaceflinger/CompositionEngine/Android.bp
index ade82f6..e2f2324 100644
--- a/services/surfaceflinger/CompositionEngine/Android.bp
+++ b/services/surfaceflinger/CompositionEngine/Android.bp
@@ -54,6 +54,7 @@
srcs: [
"src/planner/LayerState.cpp",
"src/planner/Planner.cpp",
+ "src/planner/Predictor.cpp",
"src/ClientCompositionRequestCache.cpp",
"src/CompositionEngine.cpp",
"src/Display.cpp",
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
index ae35fb0..044ddd8 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/Output.h
@@ -100,6 +100,7 @@
const ReleasedLayers& getReleasedLayersForTest() const;
void setDisplayColorProfileForTest(std::unique_ptr<compositionengine::DisplayColorProfile>);
void setRenderSurfaceForTest(std::unique_ptr<compositionengine::RenderSurface>);
+ bool plannerEnabled() const { return mPlanner != nullptr; }
protected:
std::unique_ptr<compositionengine::OutputLayer> createOutputLayer(const sp<LayerFE>&) const;
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Planner.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Planner.h
index 53eca01..ad53d27 100644
--- a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Planner.h
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Planner.h
@@ -18,9 +18,11 @@
#include <compositionengine/Output.h>
#include <compositionengine/impl/planner/LayerState.h>
+#include <compositionengine/impl/planner/Predictor.h>
#include <utils/String16.h>
#include <utils/Vector.h>
+#include <optional>
#include <string>
#include <unordered_map>
@@ -39,10 +41,23 @@
void plan(
compositionengine::Output::OutputLayersEnumerator<compositionengine::Output>&& layers);
+ // Updates the Planner with the current set of layers after a composition strategy is
+ // determined.
+ void reportFinalPlan(
+ compositionengine::Output::OutputLayersEnumerator<compositionengine::Output>&& layers);
+
void dump(const Vector<String16>& args, std::string&);
private:
+ void dumpUsage(std::string&) const;
+
std::unordered_map<LayerId, LayerState> mPreviousLayers;
+
+ std::vector<const LayerState*> mCurrentLayers;
+
+ Predictor mPredictor;
+
+ std::optional<Predictor::PredictedPlan> mPredictedPlan;
};
} // namespace compositionengine::impl::planner
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Predictor.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Predictor.h
new file mode 100644
index 0000000..38c73f7
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/Predictor.h
@@ -0,0 +1,278 @@
+/*
+ * Copyright 2021 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.
+ */
+
+#pragma once
+
+#include <compositionengine/impl/planner/LayerState.h>
+
+namespace android::compositionengine::impl::planner {
+
+class LayerStack {
+public:
+ LayerStack(const std::vector<const LayerState*>& layers) : mLayers(copyLayers(layers)) {}
+
+ struct ApproximateMatch {
+ bool operator==(const ApproximateMatch& other) const {
+ return differingIndex == other.differingIndex &&
+ differingFields == other.differingFields;
+ }
+
+ size_t differingIndex;
+ Flags<LayerStateField> differingFields;
+ };
+
+ std::optional<ApproximateMatch> getApproximateMatch(
+ const std::vector<const LayerState*>& other) const;
+
+ void compare(const LayerStack& other, std::string& result) const {
+ if (mLayers.size() != other.mLayers.size()) {
+ base::StringAppendF(&result, "Cannot compare stacks of different sizes (%zd vs. %zd)\n",
+ mLayers.size(), other.mLayers.size());
+ return;
+ }
+
+ for (size_t l = 0; l < mLayers.size(); ++l) {
+ const auto& thisLayer = mLayers[l];
+ const auto& otherLayer = other.mLayers[l];
+ base::StringAppendF(&result, "\n+ - - - - - - - - - Layer %d [%s]\n", thisLayer.getId(),
+ thisLayer.getName().c_str());
+ auto comparisonOpt = thisLayer.compare(otherLayer);
+ base::StringAppendF(&result,
+ " %s + - - - - - - - - - - - - - - - - - - - - - - - "
+ "- Layer %d [%s]\n",
+ comparisonOpt ? " " : "Identical", otherLayer.getId(),
+ otherLayer.getName().c_str());
+ if (comparisonOpt) {
+ result.append(*comparisonOpt);
+ }
+ }
+ }
+
+ void dump(std::string& result) const {
+ for (const LayerState& layer : mLayers) {
+ base::StringAppendF(&result, "+ - - - - - - - - - Layer %d [%s]\n", layer.getId(),
+ layer.getName().c_str());
+ layer.dump(result);
+ }
+ }
+
+ void dumpLayerNames(std::string& result, const std::string& prefix = " ") const {
+ for (const LayerState& layer : mLayers) {
+ result.append(prefix);
+ result.append(layer.getName());
+ result.append("\n");
+ }
+ }
+
+private:
+ std::vector<const LayerState> copyLayers(const std::vector<const LayerState*>& layers) {
+ std::vector<const LayerState> copiedLayers;
+ copiedLayers.reserve(layers.size());
+ std::transform(layers.cbegin(), layers.cend(), std::back_inserter(copiedLayers),
+ [](const LayerState* layerState) { return *layerState; });
+ return copiedLayers;
+ }
+
+ std::vector<const LayerState> mLayers;
+
+ // TODO(b/180976743): Tune kMaxDifferingFields
+ constexpr static int kMaxDifferingFields = 6;
+};
+
+class Plan {
+public:
+ static std::optional<Plan> fromString(const std::string&);
+
+ void reset() { mLayerTypes.clear(); }
+ void addLayerType(hardware::graphics::composer::hal::Composition type) {
+ mLayerTypes.emplace_back(type);
+ }
+
+ friend std::string to_string(const Plan& plan);
+
+ friend bool operator==(const Plan& lhs, const Plan& rhs) {
+ return lhs.mLayerTypes == rhs.mLayerTypes;
+ }
+ friend bool operator!=(const Plan& lhs, const Plan& rhs) { return !(lhs == rhs); }
+
+private:
+ std::vector<hardware::graphics::composer::hal::Composition> mLayerTypes;
+};
+
+} // namespace android::compositionengine::impl::planner
+
+namespace std {
+template <>
+struct hash<android::compositionengine::impl::planner::Plan> {
+ size_t operator()(const android::compositionengine::impl::planner::Plan& plan) const {
+ return std::hash<std::string>{}(to_string(plan));
+ }
+};
+} // namespace std
+
+namespace android::compositionengine::impl::planner {
+
+class Prediction {
+public:
+ enum class Type {
+ Exact,
+ Approximate,
+ Total,
+ };
+
+ friend std::string to_string(Type type) {
+ using namespace std::string_literals;
+
+ switch (type) {
+ case Type::Exact:
+ return "Exact";
+ case Type::Approximate:
+ return "Approximate";
+ case Type::Total:
+ return "Total";
+ }
+ }
+
+ Prediction(const std::vector<const LayerState*>& layers, Plan plan)
+ : mExampleLayerStack(layers), mPlan(std::move(plan)) {}
+
+ const LayerStack& getExampleLayerStack() const { return mExampleLayerStack; }
+ const Plan& getPlan() const { return mPlan; }
+
+ size_t getHitCount(Type type) const {
+ if (type == Type::Total) {
+ return getHitCount(Type::Exact) + getHitCount(Type::Approximate);
+ }
+ return getStatsForType(type).hitCount;
+ }
+
+ size_t getMissCount(Type type) const {
+ if (type == Type::Total) {
+ return getMissCount(Type::Exact) + getMissCount(Type::Approximate);
+ }
+ return getStatsForType(type).missCount;
+ }
+
+ void recordHit(Type type) { ++getStatsForType(type).hitCount; }
+
+ void recordMiss(Type type) { ++getStatsForType(type).missCount; }
+
+ void dump(std::string&) const;
+
+private:
+ struct Stats {
+ void dump(std::string& result) const {
+ const size_t totalAttempts = hitCount + missCount;
+ base::StringAppendF(&result, "%.2f%% (%zd/%zd)", 100.0f * hitCount / totalAttempts,
+ hitCount, totalAttempts);
+ }
+
+ size_t hitCount = 0;
+ size_t missCount = 0;
+ };
+
+ const Stats& getStatsForType(Type type) const {
+ return (type == Type::Exact) ? mExactStats : mApproximateStats;
+ }
+
+ Stats& getStatsForType(Type type) {
+ return const_cast<Stats&>(const_cast<const Prediction*>(this)->getStatsForType(type));
+ }
+
+ LayerStack mExampleLayerStack;
+ Plan mPlan;
+
+ Stats mExactStats;
+ Stats mApproximateStats;
+};
+
+class Predictor {
+public:
+ struct PredictedPlan {
+ NonBufferHash hash;
+ Plan plan;
+ Prediction::Type type;
+ };
+
+ std::optional<PredictedPlan> getPredictedPlan(const std::vector<const LayerState*>&,
+ NonBufferHash) const;
+
+ void recordResult(std::optional<PredictedPlan> predictedPlan,
+ const std::vector<const LayerState*>&, Plan result);
+
+ void dump(std::string&) const;
+
+ void compareLayerStacks(NonBufferHash leftHash, NonBufferHash rightHash, std::string&) const;
+ void describeLayerStack(NonBufferHash, std::string&) const;
+ void listSimilarStacks(Plan, std::string&) const;
+
+private:
+ // Retrieves a prediction from either the main prediction list or from the candidate list
+ const Prediction& getPrediction(NonBufferHash) const;
+ Prediction& getPrediction(NonBufferHash);
+
+ std::optional<Plan> getExactMatch(NonBufferHash) const;
+ std::optional<NonBufferHash> getApproximateMatch(
+ const std::vector<const LayerState*>& layers) const;
+
+ void promoteIfCandidate(NonBufferHash);
+ void recordPredictedResult(PredictedPlan, const std::vector<const LayerState*>& layers,
+ Plan result);
+ bool findSimilarPrediction(const std::vector<const LayerState*>& layers, Plan result);
+
+ void dumpPredictionsByFrequency(std::string&) const;
+
+ struct PromotionCandidate {
+ PromotionCandidate(NonBufferHash hash, Prediction&& prediction)
+ : hash(hash), prediction(std::move(prediction)) {}
+
+ NonBufferHash hash;
+ Prediction prediction;
+ };
+
+ static constexpr const size_t MAX_CANDIDATES = 4;
+ std::deque<PromotionCandidate> mCandidates;
+ decltype(mCandidates)::const_iterator getCandidateEntryByHash(NonBufferHash hash) const {
+ const auto candidateMatches = [&](const PromotionCandidate& candidate) {
+ return candidate.hash == hash;
+ };
+
+ return std::find_if(mCandidates.cbegin(), mCandidates.cend(), candidateMatches);
+ }
+
+ std::unordered_map<NonBufferHash, Prediction> mPredictions;
+ std::unordered_map<Plan, std::vector<NonBufferHash>> mSimilarStacks;
+
+ struct ApproximateStack {
+ ApproximateStack(NonBufferHash hash, LayerStack::ApproximateMatch match)
+ : hash(hash), match(match) {}
+
+ bool operator==(const ApproximateStack& other) const {
+ return hash == other.hash && match == other.match;
+ }
+
+ NonBufferHash hash;
+ LayerStack::ApproximateMatch match;
+ };
+
+ std::vector<ApproximateStack> mApproximateStacks;
+
+ mutable size_t mExactHitCount = 0;
+ mutable size_t mApproximateHitCount = 0;
+ mutable size_t mMissCount = 0;
+};
+
+} // namespace android::compositionengine::impl::planner
diff --git a/services/surfaceflinger/CompositionEngine/src/Output.cpp b/services/surfaceflinger/CompositionEngine/src/Output.cpp
index 709d7c9..57b7481 100644
--- a/services/surfaceflinger/CompositionEngine/src/Output.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/Output.cpp
@@ -873,6 +873,10 @@
chooseCompositionStrategy();
+ if (mPlanner) {
+ mPlanner->reportFinalPlan(getOutputLayersOrderedByZ());
+ }
+
mRenderSurface->prepareFrame(outputState.usesClientComposition,
outputState.usesDeviceComposition);
}
diff --git a/services/surfaceflinger/CompositionEngine/src/planner/Planner.cpp b/services/surfaceflinger/CompositionEngine/src/planner/Planner.cpp
index 30f4892..619d008 100644
--- a/services/surfaceflinger/CompositionEngine/src/planner/Planner.cpp
+++ b/services/surfaceflinger/CompositionEngine/src/planner/Planner.cpp
@@ -32,6 +32,7 @@
std::inserter(removedLayers, removedLayers.begin()),
[](const auto& layer) { return layer.first; });
+ std::vector<LayerId> currentLayerIds;
for (auto layer : layers) {
LayerId id = layer->getLayerFE().getSequence();
if (const auto layerEntry = mPreviousLayers.find(id); layerEntry != mPreviousLayers.end()) {
@@ -54,6 +55,8 @@
mPreviousLayers.emplace(std::make_pair(id, std::move(state)));
}
+ currentLayerIds.emplace_back(id);
+
if (const auto found = removedLayers.find(id); found != removedLayers.end()) {
removedLayers.erase(found);
}
@@ -67,10 +70,153 @@
mPreviousLayers.erase(removedLayer);
}
}
+
+ mCurrentLayers.clear();
+ mCurrentLayers.reserve(currentLayerIds.size());
+ std::transform(currentLayerIds.cbegin(), currentLayerIds.cend(),
+ std::back_inserter(mCurrentLayers),
+ [this](LayerId id) { return &mPreviousLayers.at(id); });
+
+ mPredictedPlan = mPredictor.getPredictedPlan(mCurrentLayers, getNonBufferHash(mCurrentLayers));
+ if (mPredictedPlan) {
+ ALOGV("[%s] Predicting plan %s", __func__, to_string(mPredictedPlan->plan).c_str());
+ } else {
+ ALOGV("[%s] No prediction found\n", __func__);
+ }
}
-void Planner::dump(const Vector<String16>& /* args */, std::string& result) {
- result.append("Dumping Planner state");
+void Planner::reportFinalPlan(
+ compositionengine::Output::OutputLayersEnumerator<compositionengine::Output>&& layers) {
+ Plan finalPlan;
+ for (auto layer : layers) {
+ const bool forcedOrRequestedClient =
+ layer->getState().forceClientComposition || layer->requiresClientComposition();
+
+ finalPlan.addLayerType(
+ forcedOrRequestedClient
+ ? hardware::graphics::composer::hal::Composition::CLIENT
+ : layer->getLayerFE().getCompositionState()->compositionType);
+ }
+
+ mPredictor.recordResult(mPredictedPlan, mCurrentLayers, finalPlan);
+}
+
+void Planner::dump(const Vector<String16>& args, std::string& result) {
+ if (args.size() > 1) {
+ const String8 command(args[1]);
+ if (command == "--compare" || command == "-c") {
+ if (args.size() < 4) {
+ base::StringAppendF(&result,
+ "Expected two layer stack hashes, e.g. '--planner %s "
+ "<left_hash> <right_hash>'\n",
+ command.string());
+ return;
+ }
+ if (args.size() > 4) {
+ base::StringAppendF(&result,
+ "Too many arguments found, expected '--planner %s <left_hash> "
+ "<right_hash>'\n",
+ command.string());
+ return;
+ }
+
+ const String8 leftHashString(args[2]);
+ size_t leftHash = 0;
+ int fieldsRead = sscanf(leftHashString.string(), "%zx", &leftHash);
+ if (fieldsRead != 1) {
+ base::StringAppendF(&result, "Failed to parse %s as a size_t\n",
+ leftHashString.string());
+ return;
+ }
+
+ const String8 rightHashString(args[3]);
+ size_t rightHash = 0;
+ fieldsRead = sscanf(rightHashString.string(), "%zx", &rightHash);
+ if (fieldsRead != 1) {
+ base::StringAppendF(&result, "Failed to parse %s as a size_t\n",
+ rightHashString.string());
+ return;
+ }
+
+ mPredictor.compareLayerStacks(leftHash, rightHash, result);
+ } else if (command == "--describe" || command == "-d") {
+ if (args.size() < 3) {
+ base::StringAppendF(&result,
+ "Expected a layer stack hash, e.g. '--planner %s <hash>'\n",
+ command.string());
+ return;
+ }
+ if (args.size() > 3) {
+ base::StringAppendF(&result,
+ "Too many arguments found, expected '--planner %s <hash>'\n",
+ command.string());
+ return;
+ }
+
+ const String8 hashString(args[2]);
+ size_t hash = 0;
+ const int fieldsRead = sscanf(hashString.string(), "%zx", &hash);
+ if (fieldsRead != 1) {
+ base::StringAppendF(&result, "Failed to parse %s as a size_t\n",
+ hashString.string());
+ return;
+ }
+
+ mPredictor.describeLayerStack(hash, result);
+ } else if (command == "--help" || command == "-h") {
+ dumpUsage(result);
+ } else if (command == "--similar" || command == "-s") {
+ if (args.size() < 3) {
+ base::StringAppendF(&result, "Expected a plan string, e.g. '--planner %s <plan>'\n",
+ command.string());
+ return;
+ }
+ if (args.size() > 3) {
+ base::StringAppendF(&result,
+ "Too many arguments found, expected '--planner %s <plan>'\n",
+ command.string());
+ return;
+ }
+
+ const String8 planString(args[2]);
+ std::optional<Plan> plan = Plan::fromString(std::string(planString.string()));
+ if (!plan) {
+ base::StringAppendF(&result, "Failed to parse %s as a Plan\n", planString.string());
+ return;
+ }
+
+ mPredictor.listSimilarStacks(*plan, result);
+ } else {
+ base::StringAppendF(&result, "Unknown command '%s'\n\n", command.string());
+ dumpUsage(result);
+ }
+ return;
+ }
+
+ // If there are no specific commands, dump the usual state
+ mPredictor.dump(result);
+}
+
+void Planner::dumpUsage(std::string& result) const {
+ result.append("Planner command line interface usage\n");
+ result.append(" dumpsys SurfaceFlinger --planner <command> [arguments]\n\n");
+
+ result.append("If run without a command, dumps current Planner state\n\n");
+
+ result.append("Commands:\n");
+
+ result.append("[--compare|-c] <left_hash> <right_hash>\n");
+ result.append(" Compares the predictions <left_hash> and <right_hash> by showing differences"
+ " in their example layer stacks\n");
+
+ result.append("[--describe|-d] <hash>\n");
+ result.append(" Prints the example layer stack and prediction statistics for <hash>\n");
+
+ result.append("[--help|-h]\n");
+ result.append(" Shows this message\n");
+
+ result.append("[--similar|-s] <plan>\n");
+ result.append(" Prints the example layer names for similar stacks matching <plan>\n");
}
} // namespace android::compositionengine::impl::planner
diff --git a/services/surfaceflinger/CompositionEngine/src/planner/Predictor.cpp b/services/surfaceflinger/CompositionEngine/src/planner/Predictor.cpp
new file mode 100644
index 0000000..28be9db
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/src/planner/Predictor.cpp
@@ -0,0 +1,479 @@
+/*
+ * Copyright 2021 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
+
+#undef LOG_TAG
+#define LOG_TAG "Planner"
+
+#include <compositionengine/impl/planner/Predictor.h>
+
+namespace android::compositionengine::impl::planner {
+
+std::optional<LayerStack::ApproximateMatch> LayerStack::getApproximateMatch(
+ const std::vector<const LayerState*>& other) const {
+ // Differing numbers of layers are never an approximate match
+ if (mLayers.size() != other.size()) {
+ return std::nullopt;
+ }
+
+ std::optional<ApproximateMatch> approximateMatch = {};
+ for (size_t i = 0; i < mLayers.size(); ++i) {
+ // Skip identical layers
+ if (mLayers[i].getHash(LayerStateField::Buffer) ==
+ other[i]->getHash(LayerStateField::Buffer)) {
+ continue;
+ }
+
+ // Skip layers where both are client-composited, since that doesn't change the
+ // composition plan
+ if (mLayers[i].getCompositionType() == hal::Composition::CLIENT &&
+ other[i]->getCompositionType() == hal::Composition::CLIENT) {
+ continue;
+ }
+
+ // If layers differ in composition type, their stacks are too different
+ if (mLayers[i].getCompositionType() != other[i]->getCompositionType()) {
+ return std::nullopt;
+ }
+
+ // If layers are not identical, but we already have a prior approximate match,
+ // the LayerStacks differ by too much, so return nothing
+ if (approximateMatch) {
+ return std::nullopt;
+ }
+
+ Flags<LayerStateField> differingFields =
+ mLayers[i].getDifferingFields(*other[i], LayerStateField::Buffer);
+
+ // If we don't find an approximate match on this layer, then the LayerStacks differ
+ // by too much, so return nothing
+ const int differingFieldCount = __builtin_popcount(differingFields.get());
+ if (differingFieldCount <= kMaxDifferingFields) {
+ approximateMatch = ApproximateMatch{
+ .differingIndex = i,
+ .differingFields = differingFields,
+ };
+ } else {
+ return std::nullopt;
+ }
+ }
+
+ // If we make it through the layer-by-layer comparison without an approximate match,
+ // it means that all layers were either identical or had client-composited layers in common,
+ // which don't affect the composition strategy, so return a successful result with
+ // no differences.
+ return ApproximateMatch{
+ .differingIndex = 0,
+ .differingFields = {},
+ };
+}
+
+std::optional<Plan> Plan::fromString(const std::string& string) {
+ Plan plan;
+ for (char c : string) {
+ switch (c) {
+ case 'C':
+ plan.addLayerType(hal::Composition::CLIENT);
+ continue;
+ case 'U':
+ plan.addLayerType(hal::Composition::CURSOR);
+ continue;
+ case 'D':
+ plan.addLayerType(hal::Composition::DEVICE);
+ continue;
+ case 'I':
+ plan.addLayerType(hal::Composition::INVALID);
+ continue;
+ case 'B':
+ plan.addLayerType(hal::Composition::SIDEBAND);
+ continue;
+ case 'S':
+ plan.addLayerType(hal::Composition::SOLID_COLOR);
+ continue;
+ default:
+ return std::nullopt;
+ }
+ }
+ return plan;
+}
+
+std::string to_string(const Plan& plan) {
+ std::string result;
+ for (auto type : plan.mLayerTypes) {
+ switch (type) {
+ case hal::Composition::CLIENT:
+ result.append("C");
+ break;
+ case hal::Composition::CURSOR:
+ result.append("U");
+ break;
+ case hal::Composition::DEVICE:
+ result.append("D");
+ break;
+ case hal::Composition::INVALID:
+ result.append("I");
+ break;
+ case hal::Composition::SIDEBAND:
+ result.append("B");
+ break;
+ case hal::Composition::SOLID_COLOR:
+ result.append("S");
+ break;
+ }
+ }
+ return result;
+}
+
+void Prediction::dump(std::string& result) const {
+ result.append(to_string(mPlan));
+ result.append(" [Exact ");
+ mExactStats.dump(result);
+ result.append("] [Approximate ");
+ mApproximateStats.dump(result);
+ result.append("]");
+}
+
+std::optional<Predictor::PredictedPlan> Predictor::getPredictedPlan(
+ const std::vector<const LayerState*>& layers, NonBufferHash hash) const {
+ // First check for an exact match
+ if (std::optional<Plan> exactMatch = getExactMatch(hash); exactMatch) {
+ ALOGV("[%s] Found an exact match for %zx", __func__, hash);
+ return PredictedPlan{.hash = hash, .plan = *exactMatch, .type = Prediction::Type::Exact};
+ }
+
+ // If only a hash was passed in for a layer stack with a cached set, don't perform
+ // approximate matches and return early
+ if (layers.empty()) {
+ ALOGV("[%s] Only hash was passed, but no exact match was found", __func__);
+ return std::nullopt;
+ }
+
+ // Then check for approximate matches
+ if (std::optional<NonBufferHash> approximateMatch = getApproximateMatch(layers);
+ approximateMatch) {
+ ALOGV("[%s] Found an approximate match for %zx", __func__, *approximateMatch);
+ const Prediction& prediction = getPrediction(*approximateMatch);
+ return PredictedPlan{.hash = *approximateMatch,
+ .plan = prediction.getPlan(),
+ .type = Prediction::Type::Approximate};
+ }
+
+ return std::nullopt;
+}
+
+void Predictor::recordResult(std::optional<PredictedPlan> predictedPlan,
+ const std::vector<const LayerState*>& layers, Plan result) {
+ if (predictedPlan) {
+ recordPredictedResult(*predictedPlan, layers, std::move(result));
+ return;
+ }
+
+ ++mMissCount;
+
+ if (findSimilarPrediction(layers, result)) {
+ return;
+ }
+
+ const NonBufferHash hash = getNonBufferHash(layers);
+
+ ALOGV("[%s] Adding novel candidate %zx", __func__, hash);
+ mCandidates.emplace_front(hash, Prediction(layers, result));
+ if (mCandidates.size() > MAX_CANDIDATES) {
+ mCandidates.pop_back();
+ }
+}
+
+void Predictor::dump(std::string& result) const {
+ result.append("Predictor state:\n");
+
+ const size_t hitCount = mExactHitCount + mApproximateHitCount;
+ const size_t totalAttempts = hitCount + mMissCount;
+ base::StringAppendF(&result, "Global non-skipped hit rate: %.2f%% (%zd/%zd)\n",
+ 100.0f * hitCount / totalAttempts, hitCount, totalAttempts);
+ base::StringAppendF(&result, " Exact hits: %zd\n", mExactHitCount);
+ base::StringAppendF(&result, " Approximate hits: %zd\n", mApproximateHitCount);
+ base::StringAppendF(&result, " Misses: %zd\n\n", mMissCount);
+
+ dumpPredictionsByFrequency(result);
+}
+
+void Predictor::compareLayerStacks(NonBufferHash leftHash, NonBufferHash rightHash,
+ std::string& result) const {
+ const auto& [leftPredictionEntry, rightPredictionEntry] =
+ std::make_tuple(mPredictions.find(leftHash), mPredictions.find(rightHash));
+ if (leftPredictionEntry == mPredictions.end()) {
+ base::StringAppendF(&result, "No prediction found for %zx\n", leftHash);
+ return;
+ }
+ if (rightPredictionEntry == mPredictions.end()) {
+ base::StringAppendF(&result, "No prediction found for %zx\n", rightHash);
+ return;
+ }
+
+ base::StringAppendF(&result,
+ "Comparing %-16zx %-16zx\n",
+ leftHash, rightHash);
+
+ const auto& [leftPrediction, rightPrediction] =
+ std::make_tuple(leftPredictionEntry->second, rightPredictionEntry->second);
+ const auto& [leftStack, rightStack] = std::make_tuple(leftPrediction.getExampleLayerStack(),
+ rightPrediction.getExampleLayerStack());
+ leftStack.compare(rightStack, result);
+}
+
+void Predictor::describeLayerStack(NonBufferHash hash, std::string& result) const {
+ base::StringAppendF(&result, "Describing %zx:\n\n", hash);
+
+ if (const auto predictionsEntry = mPredictions.find(hash);
+ predictionsEntry != mPredictions.cend()) {
+ const auto& [hash, prediction] = *predictionsEntry;
+
+ prediction.getExampleLayerStack().dump(result);
+
+ result.append("Prediction: ");
+ prediction.dump(result);
+ result.append("\n");
+ } else {
+ result.append("No predictions found\n");
+ }
+}
+
+void Predictor::listSimilarStacks(Plan plan, std::string& result) const {
+ base::StringAppendF(&result, "Similar stacks for plan %s:\n", to_string(plan).c_str());
+
+ if (const auto similarStacksEntry = mSimilarStacks.find(plan);
+ similarStacksEntry != mSimilarStacks.end()) {
+ const auto& [_, similarStacks] = *similarStacksEntry;
+ for (NonBufferHash hash : similarStacks) {
+ base::StringAppendF(&result, "\nPrediction hash %zx:\n", hash);
+ const Prediction& prediction = mPredictions.at(hash);
+ prediction.getExampleLayerStack().dumpLayerNames(result);
+ }
+ } else {
+ result.append("No similar stacks found\n");
+ }
+}
+
+const Prediction& Predictor::getPrediction(NonBufferHash hash) const {
+ if (const auto predictionEntry = mPredictions.find(hash);
+ predictionEntry != mPredictions.end()) {
+ const auto& [_, prediction] = *predictionEntry;
+ return prediction;
+ } else {
+ const auto candidateEntry = getCandidateEntryByHash(hash);
+ ALOGE_IF(candidateEntry == mCandidates.cend(),
+ "Hash should have been found in either predictions or candidates");
+ const auto& [_, prediction] = *candidateEntry;
+ return prediction;
+ }
+}
+
+Prediction& Predictor::getPrediction(NonBufferHash hash) {
+ return const_cast<Prediction&>(const_cast<const Predictor*>(this)->getPrediction(hash));
+}
+
+std::optional<Plan> Predictor::getExactMatch(NonBufferHash hash) const {
+ const Prediction* match = nullptr;
+ if (const auto predictionEntry = mPredictions.find(hash);
+ predictionEntry != mPredictions.end()) {
+ const auto& [hash, prediction] = *predictionEntry;
+ match = &prediction;
+ } else if (const auto candidateEntry = getCandidateEntryByHash(hash);
+ candidateEntry != mCandidates.cend()) {
+ match = &(candidateEntry->prediction);
+ }
+
+ if (match == nullptr) {
+ return std::nullopt;
+ }
+
+ if (match->getMissCount(Prediction::Type::Exact) != 0) {
+ ALOGV("[%s] Skipping exact match for %zx because of prior miss", __func__, hash);
+ return std::nullopt;
+ }
+
+ return match->getPlan();
+}
+
+std::optional<NonBufferHash> Predictor::getApproximateMatch(
+ const std::vector<const LayerState*>& layers) const {
+ const auto approximateStackMatches = [&](const ApproximateStack& approximateStack) {
+ const auto& exampleStack = mPredictions.at(approximateStack.hash).getExampleLayerStack();
+ if (const auto approximateMatchOpt = exampleStack.getApproximateMatch(layers);
+ approximateMatchOpt) {
+ return *approximateMatchOpt == approximateStack.match;
+ }
+ return false;
+ };
+
+ const auto candidateMatches = [&](const PromotionCandidate& candidate) {
+ ALOGV("[getApproximateMatch] checking against %zx", candidate.hash);
+ return candidate.prediction.getExampleLayerStack().getApproximateMatch(layers) !=
+ std::nullopt;
+ };
+
+ const Prediction* match = nullptr;
+ NonBufferHash hash;
+ if (const auto approximateStackIter =
+ std::find_if(mApproximateStacks.cbegin(), mApproximateStacks.cend(),
+ approximateStackMatches);
+ approximateStackIter != mApproximateStacks.cend()) {
+ match = &mPredictions.at(approximateStackIter->hash);
+ hash = approximateStackIter->hash;
+ } else if (const auto candidateEntry =
+ std::find_if(mCandidates.cbegin(), mCandidates.cend(), candidateMatches);
+ candidateEntry != mCandidates.cend()) {
+ match = &(candidateEntry->prediction);
+ hash = candidateEntry->hash;
+ }
+
+ if (match == nullptr) {
+ return std::nullopt;
+ }
+
+ if (match->getMissCount(Prediction::Type::Approximate) != 0) {
+ ALOGV("[%s] Skipping approximate match for %zx because of prior miss", __func__, hash);
+ return std::nullopt;
+ }
+
+ return hash;
+}
+
+void Predictor::promoteIfCandidate(NonBufferHash predictionHash) {
+ // Return if the candidate has already been promoted
+ if (mPredictions.count(predictionHash) != 0) {
+ return;
+ }
+
+ ALOGV("[%s] Promoting %zx from candidate to prediction", __func__, predictionHash);
+
+ auto candidateEntry = getCandidateEntryByHash(predictionHash);
+ ALOGE_IF(candidateEntry == mCandidates.end(), "Expected to find candidate");
+
+ mSimilarStacks[candidateEntry->prediction.getPlan()].push_back(predictionHash);
+ mPredictions.emplace(predictionHash, std::move(candidateEntry->prediction));
+ mCandidates.erase(candidateEntry);
+}
+
+void Predictor::recordPredictedResult(PredictedPlan predictedPlan,
+ const std::vector<const LayerState*>& layers, Plan result) {
+ Prediction& prediction = getPrediction(predictedPlan.hash);
+ if (prediction.getPlan() != result) {
+ ALOGV("[%s] %s prediction missed, expected %s, found %s", __func__,
+ to_string(predictedPlan.type).c_str(), to_string(prediction.getPlan()).c_str(),
+ to_string(result).c_str());
+ prediction.recordMiss(predictedPlan.type);
+ ++mMissCount;
+ return;
+ }
+
+ switch (predictedPlan.type) {
+ case Prediction::Type::Approximate:
+ ++mApproximateHitCount;
+ break;
+ case Prediction::Type::Exact:
+ ++mExactHitCount;
+ break;
+ default:
+ break;
+ }
+
+ ALOGV("[%s] %s prediction hit", __func__, to_string(predictedPlan.type).c_str());
+ ALOGV("[%s] Plan: %s", __func__, to_string(result).c_str());
+ prediction.recordHit(predictedPlan.type);
+
+ const auto stackMatchesHash = [hash = predictedPlan.hash](const ApproximateStack& stack) {
+ return stack.hash == hash;
+ };
+
+ if (predictedPlan.type == Prediction::Type::Approximate) {
+ // If this approximate match is not already in the list of approximate stacks, add it
+ if (std::find_if(mApproximateStacks.cbegin(), mApproximateStacks.cend(),
+ stackMatchesHash) == mApproximateStacks.cend()) {
+ ALOGV("[%s] Adding approximate match to list", __func__);
+ const auto approximateMatchOpt =
+ prediction.getExampleLayerStack().getApproximateMatch(layers);
+ ALOGE_IF(!approximateMatchOpt, "Expected an approximate match");
+ mApproximateStacks.emplace_back(predictedPlan.hash, *approximateMatchOpt);
+ }
+ }
+
+ promoteIfCandidate(predictedPlan.hash);
+}
+
+bool Predictor::findSimilarPrediction(const std::vector<const LayerState*>& layers, Plan result) {
+ const auto stacksEntry = mSimilarStacks.find(result);
+ if (stacksEntry == mSimilarStacks.end()) {
+ return false;
+ }
+
+ std::optional<ApproximateStack> bestMatch;
+ const auto& [plan, similarStacks] = *stacksEntry;
+ for (NonBufferHash hash : similarStacks) {
+ const Prediction& prediction = mPredictions.at(hash);
+ auto approximateMatch = prediction.getExampleLayerStack().getApproximateMatch(layers);
+ if (!approximateMatch) {
+ continue;
+ }
+
+ const int differingFieldCount = __builtin_popcount(approximateMatch->differingFields.get());
+ if (!bestMatch ||
+ differingFieldCount < __builtin_popcount(bestMatch->match.differingFields.get())) {
+ bestMatch = {hash, *approximateMatch};
+ }
+ }
+
+ if (!bestMatch) {
+ return false;
+ }
+
+ ALOGV("[%s] Adding %zx to approximate stacks", __func__, bestMatch->hash);
+
+ mApproximateStacks.emplace_back(*bestMatch);
+ return true;
+}
+
+void Predictor::dumpPredictionsByFrequency(std::string& result) const {
+ struct HashFrequency {
+ HashFrequency(NonBufferHash hash, size_t totalAttempts)
+ : hash(hash), totalAttempts(totalAttempts) {}
+
+ NonBufferHash hash;
+ size_t totalAttempts;
+ };
+
+ std::vector<HashFrequency> hashFrequencies;
+ for (const auto& [hash, prediction] : mPredictions) {
+ hashFrequencies.emplace_back(hash,
+ prediction.getHitCount(Prediction::Type::Total) +
+ prediction.getMissCount(Prediction::Type::Total));
+ }
+
+ std::sort(hashFrequencies.begin(), hashFrequencies.end(),
+ [](const HashFrequency& lhs, const HashFrequency& rhs) {
+ return lhs.totalAttempts > rhs.totalAttempts;
+ });
+
+ result.append("Predictions:\n");
+ for (const auto& [hash, totalAttempts] : hashFrequencies) {
+ base::StringAppendF(&result, " %016zx ", hash);
+ mPredictions.at(hash).dump(result);
+ result.append("\n");
+ }
+}
+
+} // namespace android::compositionengine::impl::planner
\ No newline at end of file
diff --git a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
index f654c2f..8dcace6 100644
--- a/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
+++ b/services/surfaceflinger/CompositionEngine/tests/OutputTest.cpp
@@ -891,6 +891,9 @@
mOutput.editState().usesDeviceComposition = true;
EXPECT_CALL(mOutput, chooseCompositionStrategy()).Times(1);
+ if (mOutput.plannerEnabled()) {
+ EXPECT_CALL(mOutput, getOutputLayerCount()).WillOnce(Return(0u));
+ }
EXPECT_CALL(*mRenderSurface, prepareFrame(false, true));
mOutput.prepareFrame();