[res] Speed up AssetManager pointer locking
AssetManager needs to lock (promote()) apk asset weak pointers
to use them in pretty much any operation, and often mulitple
times for the same object.
This CL introduces a concept of an 'operation' in AssetManager,
and adds a cache for the locked assets that are retained until
the end of that operation. This way we only need to lock each
assets object exactly once, losing pretty much no performance.
Benchmarks all returned to the pre-memory-safe state values.
Bug: 280951693
Bug: 197260547
Bug: 276922628
Test: UTs + native benchmarks + java benchmarks + boot
Change-Id: I26ef88df4f6267b5e8b89f1588f2382db74030c0
diff --git a/libs/androidfw/AssetManager2.cpp b/libs/androidfw/AssetManager2.cpp
index 94dbfb5..fd5d07f 100644
--- a/libs/androidfw/AssetManager2.cpp
+++ b/libs/androidfw/AssetManager2.cpp
@@ -112,7 +112,15 @@
}
void AssetManager2::BuildDynamicRefTable(ApkAssetsList apk_assets) {
- apk_assets_.assign(apk_assets.begin(), apk_assets.end());
+ auto op = StartOperation();
+
+ apk_assets_.resize(apk_assets.size());
+ for (size_t i = 0; i != apk_assets.size(); ++i) {
+ apk_assets_[i].first = apk_assets[i];
+ // Let's populate the locked assets right away as we're going to need them here later.
+ apk_assets_[i].second = apk_assets[i];
+ }
+
package_groups_.clear();
package_ids_.fill(0xff);
@@ -124,7 +132,7 @@
// Overlay resources are not directly referenced by an application so their resource ids
// can change throughout the application's lifetime. Assign overlay package ids last.
std::vector<const ApkAssets*> sorted_apk_assets;
- sorted_apk_assets.reserve(apk_assets_.size());
+ sorted_apk_assets.reserve(apk_assets.size());
for (auto& asset : apk_assets) {
sorted_apk_assets.push_back(asset.get());
}
@@ -250,9 +258,10 @@
void AssetManager2::DumpToLog() const {
LOG(INFO) << base::StringPrintf("AssetManager2(this=%p)", this);
+ auto op = StartOperation();
std::string list;
- for (const auto& apk_assets : apk_assets_) {
- auto assets = apk_assets.promote();
+ for (size_t i = 0; i < apk_assets_.size(); ++i) {
+ const auto& assets = GetApkAssets(i);
base::StringAppendF(&list, "%s,", assets ? assets->GetDebugName().c_str() : "nullptr");
}
LOG(INFO) << "ApkAssets: " << list;
@@ -290,7 +299,8 @@
if (cookie < 0 || static_cast<size_t>(cookie) >= apk_assets_.size()) {
return nullptr;
}
- auto assets = apk_assets_[cookie].promote();
+ auto op = StartOperation();
+ const auto& assets = GetApkAssets(cookie);
return assets ? assets->GetLoadedArsc()->GetStringPool() : nullptr;
}
@@ -341,9 +351,10 @@
bool AssetManager2::GetOverlayablesToString(android::StringPiece package_name,
std::string* out) const {
+ auto op = StartOperation();
uint8_t package_id = 0U;
- for (const auto& apk_assets : apk_assets_) {
- auto assets = apk_assets.promote();
+ for (size_t i = 0; i != apk_assets_.size(); ++i) {
+ const auto& assets = GetApkAssets(i);
if (!assets) {
continue;
}
@@ -400,10 +411,14 @@
}
bool AssetManager2::ContainsAllocatedTable() const {
- return std::find_if(apk_assets_.begin(), apk_assets_.end(), [](auto&& assets_weak) {
- auto assets = assets_weak.promote();
- return assets && assets->IsTableAllocated();
- }) != apk_assets_.end();
+ auto op = StartOperation();
+ for (size_t i = 0; i != apk_assets_.size(); ++i) {
+ const auto& assets = GetApkAssets(i);
+ if (assets && assets->IsTableAllocated()) {
+ return true;
+ }
+ }
+ return false;
}
void AssetManager2::SetConfiguration(const ResTable_config& configuration) {
@@ -428,8 +443,9 @@
}
if (!found_system_package) {
+ auto op = StartOperation();
for (const ConfiguredOverlay& overlay : package_group.overlays_) {
- if (auto asset = apk_assets_[overlay.cookie].promote()) {
+ if (const auto& asset = GetApkAssets(overlay.cookie)) {
non_system_overlays.insert(std::move(asset));
}
}
@@ -442,6 +458,8 @@
base::expected<std::set<ResTable_config>, IOError> AssetManager2::GetResourceConfigurations(
bool exclude_system, bool exclude_mipmap) const {
ATRACE_NAME("AssetManager::GetResourceConfigurations");
+ auto op = StartOperation();
+
const auto non_system_overlays =
exclude_system ? GetNonSystemOverlays() : std::set<ApkAssetsPtr>();
@@ -455,7 +473,7 @@
}
if (!non_system_overlays.empty()) {
// Exclude overlays that target only system resources.
- auto apk_assets = apk_assets_[package_group.cookies_[i]].promote();
+ const auto& apk_assets = GetApkAssets(package_group.cookies_[i]);
if (apk_assets && apk_assets->IsOverlay() &&
non_system_overlays.find(apk_assets) == non_system_overlays.end()) {
continue;
@@ -475,6 +493,8 @@
std::set<std::string> AssetManager2::GetResourceLocales(bool exclude_system,
bool merge_equivalent_languages) const {
ATRACE_NAME("AssetManager::GetResourceLocales");
+ auto op = StartOperation();
+
std::set<std::string> locales;
const auto non_system_overlays =
exclude_system ? GetNonSystemOverlays() : std::set<ApkAssetsPtr>();
@@ -488,7 +508,7 @@
}
if (!non_system_overlays.empty()) {
// Exclude overlays that target only system resources.
- auto apk_assets = apk_assets_[package_group.cookies_[i]].promote();
+ const auto& apk_assets = GetApkAssets(package_group.cookies_[i]);
if (apk_assets && apk_assets->IsOverlay() &&
non_system_overlays.find(apk_assets) == non_system_overlays.end()) {
continue;
@@ -516,13 +536,14 @@
std::unique_ptr<AssetDir> AssetManager2::OpenDir(const std::string& dirname) const {
ATRACE_NAME("AssetManager::OpenDir");
+ auto op = StartOperation();
std::string full_path = "assets/" + dirname;
auto files = util::make_unique<SortedVector<AssetDir::FileInfo>>();
// Start from the back.
- for (auto iter = apk_assets_.rbegin(); iter != apk_assets_.rend(); ++iter) {
- auto apk_assets = iter->promote();
+ for (size_t i = apk_assets_.size(); i > 0; --i) {
+ const auto& apk_assets = GetApkAssets(i - 1);
if (!apk_assets || apk_assets->IsOverlay()) {
continue;
}
@@ -551,8 +572,9 @@
std::unique_ptr<Asset> AssetManager2::OpenNonAsset(const std::string& filename,
Asset::AccessMode mode,
ApkAssetsCookie* out_cookie) const {
- for (int32_t i = apk_assets_.size() - 1; i >= 0; i--) {
- const auto assets = apk_assets_[i].promote();
+ auto op = StartOperation();
+ for (size_t i = apk_assets_.size(); i > 0; i--) {
+ const auto& assets = GetApkAssets(i - 1);
// Prevent RRO from modifying assets and other entries accessed by file
// path. Explicitly asking for a path in a given package (denoted by a
// cookie) is still OK.
@@ -581,7 +603,8 @@
if (cookie < 0 || static_cast<size_t>(cookie) >= apk_assets_.size()) {
return {};
}
- auto assets = apk_assets_[cookie].promote();
+ auto op = StartOperation();
+ const auto& assets = GetApkAssets(cookie);
return assets ? assets->GetAssetsProvider()->Open(filename, mode) : nullptr;
}
@@ -595,6 +618,8 @@
last_resolution_.resid = resid;
}
+ auto op = StartOperation();
+
// Might use this if density_override != 0.
ResTable_config density_override_config;
@@ -631,7 +656,7 @@
bool overlaid = false;
if (!stop_at_first_match && !ignore_configuration) {
- auto assets = apk_assets_[result->cookie].promote();
+ const auto& assets = GetApkAssets(result->cookie);
if (!assets) {
ALOGE("Found expired ApkAssets #%d for resource ID 0x%08x.", result->cookie, resid);
return base::unexpected(std::nullopt);
@@ -892,8 +917,10 @@
return {};
}
+ auto op = StartOperation();
+
const uint32_t resid = last_resolution_.resid;
- auto assets = apk_assets_[cookie].promote();
+ const auto& assets = GetApkAssets(cookie);
const auto package =
assets ? assets->GetLoadedArsc()->GetPackageById(get_package_id(resid)) : nullptr;
@@ -926,7 +953,7 @@
continue;
}
const auto prefix = kStepStrings[int(step.type) - int(Resolution::Step::Type::INITIAL)];
- auto assets = apk_assets_[step.cookie].promote();
+ const auto& assets = GetApkAssets(step.cookie);
log_stream << "\n\t" << prefix << ": " << (assets ? assets->GetDebugName() : "<null>")
<< " #" << step.cookie;
if (!step.config_name.isEmpty()) {
@@ -1458,6 +1485,37 @@
}
}
+AssetManager2::ScopedOperation AssetManager2::StartOperation() const {
+ ++number_of_running_scoped_operations_;
+ return ScopedOperation(*this);
+}
+
+void AssetManager2::FinishOperation() const {
+ if (number_of_running_scoped_operations_ < 1) {
+ ALOGW("Invalid FinishOperation() call when there's none happening");
+ return;
+ }
+ if (--number_of_running_scoped_operations_ == 0) {
+ for (auto&& [_, assets] : apk_assets_) {
+ assets.clear();
+ }
+ }
+}
+
+const AssetManager2::ApkAssetsPtr& AssetManager2::GetApkAssets(ApkAssetsCookie cookie) const {
+ DCHECK(number_of_running_scoped_operations_ > 0) << "Must have an operation running";
+
+ if (cookie < 0 || cookie >= apk_assets_.size()) {
+ static const ApkAssetsPtr empty{};
+ return empty;
+ }
+ auto& [wptr, res] = apk_assets_[cookie];
+ if (!res) {
+ res = wptr.promote();
+ }
+ return res;
+}
+
Theme::Theme(AssetManager2* asset_manager) : asset_manager_(asset_manager) {
}
@@ -1590,22 +1648,16 @@
using SourceToDestinationRuntimePackageMap = std::unordered_map<int, int>;
std::unordered_map<ApkAssetsCookie, SourceToDestinationRuntimePackageMap> src_asset_cookie_id_map;
- // Determine which ApkAssets are loaded in both theme AssetManagers.
- const auto& src_assets = source.asset_manager_->GetApkAssets();
- const auto& dest_assets = asset_manager_->GetApkAssets();
- std::vector<AssetManager2::ApkAssetsPtr> promoted_src_assets;
- promoted_src_assets.reserve(src_assets.size());
- for (const auto& src_asset : src_assets) {
- promoted_src_assets.emplace_back(src_asset.promote());
- }
+ auto op_src = source.asset_manager_->StartOperation();
+ auto op_dst = asset_manager_->StartOperation();
- for (size_t j = 0; j < dest_assets.size(); j++) {
- auto dest_asset = dest_assets[j].promote();
- if (!dest_asset) {
+ for (size_t i = 0; i < source.asset_manager_->GetApkAssetsCount(); i++) {
+ const auto& src_asset = source.asset_manager_->GetApkAssets(i);
+ if (!src_asset) {
continue;
}
- for (size_t i = 0; i < promoted_src_assets.size(); i++) {
- const auto& src_asset = promoted_src_assets[i];
+ for (int j = 0; j < asset_manager_->GetApkAssetsCount(); j++) {
+ const auto& dest_asset = asset_manager_->GetApkAssets(j);
if (src_asset != dest_asset) {
// ResourcesManager caches and reuses ApkAssets when the same apk must be present in
// multiple AssetManagers. Two ApkAssets point to the same version of the same resources
@@ -1731,4 +1783,11 @@
}
}
+AssetManager2::ScopedOperation::ScopedOperation(const AssetManager2& am) : am_(am) {
+}
+
+AssetManager2::ScopedOperation::~ScopedOperation() {
+ am_.FinishOperation();
+}
+
} // namespace android
diff --git a/libs/androidfw/include/androidfw/AssetManager2.h b/libs/androidfw/include/androidfw/AssetManager2.h
index 1f97995..cedf732 100644
--- a/libs/androidfw/include/androidfw/AssetManager2.h
+++ b/libs/androidfw/include/androidfw/AssetManager2.h
@@ -102,9 +102,20 @@
AssetManager2() = default;
explicit AssetManager2(AssetManager2&& other) = default;
-
AssetManager2(ApkAssetsList apk_assets, const ResTable_config& configuration);
+ struct ScopedOperation {
+ DISALLOW_COPY_AND_ASSIGN(ScopedOperation);
+ friend AssetManager2;
+ const AssetManager2& am_;
+ ScopedOperation(const AssetManager2& am);
+
+ public:
+ ~ScopedOperation();
+ };
+
+ [[nodiscard]] ScopedOperation StartOperation() const;
+
// Sets/resets the underlying ApkAssets for this AssetManager. The ApkAssets
// are not owned by the AssetManager, and must have a longer lifetime.
//
@@ -114,8 +125,9 @@
bool SetApkAssets(ApkAssetsList apk_assets, bool invalidate_caches = true);
bool SetApkAssets(std::initializer_list<ApkAssetsPtr> apk_assets, bool invalidate_caches = true);
- inline const std::vector<ApkAssetsWPtr>& GetApkAssets() const {
- return apk_assets_;
+ const ApkAssetsPtr& GetApkAssets(ApkAssetsCookie cookie) const;
+ int GetApkAssetsCount() const {
+ return int(apk_assets_.size());
}
// Returns the string pool for the given asset cookie.
@@ -426,9 +438,16 @@
base::expected<const ResolvedBag*, NullOrIOError> GetBag(
uint32_t resid, std::vector<uint32_t>& child_resids) const;
+ // Finish an operation that was running with the current asset manager, and clean up the
+ // promoted apk assets when the last operation ends.
+ void FinishOperation() const;
+
// The ordered list of ApkAssets to search. These are not owned by the AssetManager, and must
// have a longer lifetime.
- std::vector<ApkAssetsWPtr> apk_assets_;
+ // The second pair element is the promoted version of the assets, that is held for the duration
+ // of the currently running operation. FinishOperation() clears all promoted assets to make sure
+ // they can be released when the system needs that.
+ mutable std::vector<std::pair<ApkAssetsWPtr, ApkAssetsPtr>> apk_assets_;
// DynamicRefTables for shared library package resolution.
// These are ordered according to apk_assets_. The mappings may change depending on what is
@@ -455,6 +474,10 @@
// Cached set of resolved resource values.
mutable std::unordered_map<uint32_t, SelectedValue> cached_resolved_values_;
+ // Tracking the number of the started operations running with the current AssetManager.
+ // Finishing the last one clears all promoted apk assets.
+ mutable int number_of_running_scoped_operations_ = 0;
+
// Whether or not to save resource resolution steps
bool resource_resolution_logging_enabled_ = false;
diff --git a/libs/androidfw/tests/AssetManager2_test.cpp b/libs/androidfw/tests/AssetManager2_test.cpp
index 5a5bafdf..df3fa02 100644
--- a/libs/androidfw/tests/AssetManager2_test.cpp
+++ b/libs/androidfw/tests/AssetManager2_test.cpp
@@ -207,11 +207,11 @@
AssetManager2 assetmanager;
assetmanager.SetApkAssets({overlayable_assets_, overlay_assets_, lib_one_assets_});
- auto apk_assets = assetmanager.GetApkAssets();
- ASSERT_EQ(3, apk_assets.size());
- ASSERT_EQ(overlayable_assets_, apk_assets[0].promote());
- ASSERT_EQ(overlay_assets_, apk_assets[1].promote());
- ASSERT_EQ(lib_one_assets_, apk_assets[2].promote());
+ ASSERT_EQ(3, assetmanager.GetApkAssetsCount());
+ auto op = assetmanager.StartOperation();
+ ASSERT_EQ(overlayable_assets_, assetmanager.GetApkAssets(0));
+ ASSERT_EQ(overlay_assets_, assetmanager.GetApkAssets(1));
+ ASSERT_EQ(lib_one_assets_, assetmanager.GetApkAssets(2));
auto get_first_package_id = [&assetmanager](auto apkAssets) -> uint8_t {
return assetmanager.GetAssignedPackageId(apkAssets->GetLoadedArsc()->GetPackages()[0].get());
@@ -834,4 +834,26 @@
std::string::npos);
}
+TEST_F(AssetManager2Test, GetApkAssets) {
+ AssetManager2 assetmanager;
+ assetmanager.SetApkAssets({overlayable_assets_, overlay_assets_, lib_one_assets_});
+
+ ASSERT_EQ(3, assetmanager.GetApkAssetsCount());
+ EXPECT_EQ(1, overlayable_assets_->getStrongCount());
+ EXPECT_EQ(1, overlay_assets_->getStrongCount());
+ EXPECT_EQ(1, lib_one_assets_->getStrongCount());
+
+ {
+ auto op = assetmanager.StartOperation();
+ ASSERT_EQ(overlayable_assets_, assetmanager.GetApkAssets(0));
+ ASSERT_EQ(overlay_assets_, assetmanager.GetApkAssets(1));
+ EXPECT_EQ(2, overlayable_assets_->getStrongCount());
+ EXPECT_EQ(2, overlay_assets_->getStrongCount());
+ EXPECT_EQ(1, lib_one_assets_->getStrongCount());
+ }
+ EXPECT_EQ(1, overlayable_assets_->getStrongCount());
+ EXPECT_EQ(1, overlay_assets_->getStrongCount());
+ EXPECT_EQ(1, lib_one_assets_->getStrongCount());
+}
+
} // namespace android
diff --git a/libs/androidfw/tests/Idmap_test.cpp b/libs/androidfw/tests/Idmap_test.cpp
index 568e041..60aa7d8 100644
--- a/libs/androidfw/tests/Idmap_test.cpp
+++ b/libs/androidfw/tests/Idmap_test.cpp
@@ -66,9 +66,9 @@
std::string GetStringFromApkAssets(const AssetManager2& asset_manager,
const AssetManager2::SelectedValue& value) {
- auto assets = asset_manager.GetApkAssets();
+ auto op = asset_manager.StartOperation();
const ResStringPool* string_pool =
- assets[value.cookie].promote()->GetLoadedArsc()->GetStringPool();
+ asset_manager.GetApkAssets(value.cookie)->GetLoadedArsc()->GetStringPool();
return GetStringFromPool(string_pool, value.data);
}