[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

6 files changed, 264 insertions, 133 deletions

diff --git a/core/jni/android_util_AssetManager.cpp b/core/jni/android_util_AssetManager.cpp
index d3bfcbda90bc..fc53a766b772 100644
--- a/core/jni/android_util_AssetManager.cpp
+++ b/core/jni/android_util_AssetManager.cpp
@@ -17,6 +17,9 @@
 #define ATRACE_TAG ATRACE_TAG_RESOURCES
 #define LOG_TAG "asset"
 
+#include "android_runtime/android_util_AssetManager.h"
+
+#include <errno.h>
 #include <inttypes.h>
 #include <linux/capability.h>
 #include <stdio.h>
@@ -31,7 +34,7 @@
 #include "android-base/logging.h"
 #include "android-base/properties.h"
 #include "android-base/stringprintf.h"
-#include "android_runtime/android_util_AssetManager.h"
+#include "android_content_res_ApkAssets.h"
 #include "android_runtime/AndroidRuntime.h"
 #include "android_util_Binder.h"
 #include "androidfw/Asset.h"
@@ -39,11 +42,9 @@
 #include "androidfw/AssetManager2.h"
 #include "androidfw/AttributeResolution.h"
 #include "androidfw/MutexGuard.h"
-#include <androidfw/ResourceTimer.h>
+#include "androidfw/ResourceTimer.h"
 #include "androidfw/ResourceTypes.h"
 #include "androidfw/ResourceUtils.h"
-
-#include "android_content_res_ApkAssets.h"
 #include "core_jni_helpers.h"
 #include "jni.h"
 #include "nativehelper/JNIPlatformHelp.h"
@@ -161,9 +162,30 @@ static Guarded<AssetManager2>& AssetManagerFromLong(jlong ptr) {
   return *AssetManagerForNdkAssetManager(reinterpret_cast<AAssetManager*>(ptr));
 }
 
+struct ScopedLockedAssetsOperation {
+  ScopedLockedAssetsOperation(Guarded<AssetManager2>& guarded_am)
+        : am_(guarded_am), op_(am_->StartOperation()) {}
+
+  AssetManager2& operator*() { return *am_; }
+
+  AssetManager2* operator->() { return am_.get(); }
+
+  AssetManager2* get() { return am_.get(); }
+
+  private:
+  DISALLOW_COPY_AND_ASSIGN(ScopedLockedAssetsOperation);
+
+  ScopedLock<AssetManager2> am_;
+  AssetManager2::ScopedOperation op_;
+};
+
+ScopedLockedAssetsOperation LockAndStartAssetManager(jlong ptr) {
+  return ScopedLockedAssetsOperation(AssetManagerFromLong(ptr));
+}
+
 static jobject NativeGetOverlayableMap(JNIEnv* env, jclass /*clazz*/, jlong ptr,
                                        jstring package_name) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   const ScopedUtfChars package_name_utf8(env, package_name);
   CHECK(package_name_utf8.c_str() != nullptr);
   const std::string std_package_name(package_name_utf8.c_str());
@@ -209,7 +231,7 @@ static jobject NativeGetOverlayableMap(JNIEnv* env, jclass /*clazz*/, jlong ptr,
 
 static jstring NativeGetOverlayablesToString(JNIEnv* env, jclass /*clazz*/, jlong ptr,
                                              jstring package_name) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   const ScopedUtfChars package_name_utf8(env, package_name);
   CHECK(package_name_utf8.c_str() != nullptr);
   const std::string std_package_name(package_name_utf8.c_str());
@@ -320,7 +342,7 @@ static void NativeSetApkAssets(JNIEnv* env, jclass /*clazz*/, jlong ptr,
     apk_assets.emplace_back(*scoped_assets);
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   assetmanager->SetApkAssets(apk_assets, invalidate_caches);
 }
 
@@ -370,14 +392,14 @@ static void NativeSetConfiguration(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
   configuration.screenLayout2 =
       static_cast<uint8_t>((screen_layout & kScreenLayoutRoundMask) >> kScreenLayoutRoundShift);
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   assetmanager->SetConfiguration(configuration);
 }
 
 static jobject NativeGetAssignedPackageIdentifiers(JNIEnv* env, jclass /*clazz*/, jlong ptr,
                                                    jboolean includeOverlays,
                                                    jboolean includeLoaders) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
 
   jobject sparse_array =
         env->NewObject(gSparseArrayOffsets.classObject, gSparseArrayOffsets.constructor);
@@ -407,7 +429,7 @@ static jobject NativeGetAssignedPackageIdentifiers(JNIEnv* env, jclass /*clazz*/
 }
 
 static jboolean ContainsAllocatedTable(JNIEnv* env, jclass /*clazz*/, jlong ptr) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   return assetmanager->ContainsAllocatedTable();
 }
 
@@ -418,7 +440,7 @@ static jobjectArray NativeList(JNIEnv* env, jclass /*clazz*/, jlong ptr, jstring
     return nullptr;
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<AssetDir> asset_dir =
       assetmanager->OpenDir(path_utf8.c_str());
   if (asset_dir == nullptr) {
@@ -466,7 +488,7 @@ static jlong NativeOpenAsset(JNIEnv* env, jclass /*clazz*/, jlong ptr, jstring a
     return 0;
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<Asset> asset =
       assetmanager->Open(asset_path_utf8.c_str(), static_cast<Asset::AccessMode>(access_mode));
   if (!asset) {
@@ -486,7 +508,7 @@ static jobject NativeOpenAssetFd(JNIEnv* env, jclass /*clazz*/, jlong ptr, jstri
 
   ATRACE_NAME(base::StringPrintf("AssetManager::OpenAssetFd(%s)", asset_path_utf8.c_str()).c_str());
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<Asset> asset = assetmanager->Open(asset_path_utf8.c_str(), Asset::ACCESS_RANDOM);
   if (!asset) {
     jniThrowException(env, "java/io/FileNotFoundException", asset_path_utf8.c_str());
@@ -512,7 +534,7 @@ static jlong NativeOpenNonAsset(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint j
     return 0;
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<Asset> asset;
   if (cookie != kInvalidCookie) {
     asset = assetmanager->OpenNonAsset(asset_path_utf8.c_str(), cookie,
@@ -540,7 +562,7 @@ static jobject NativeOpenNonAssetFd(JNIEnv* env, jclass /*clazz*/, jlong ptr, ji
 
   ATRACE_NAME(base::StringPrintf("AssetManager::OpenNonAssetFd(%s)", asset_path_utf8.c_str()).c_str());
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<Asset> asset;
   if (cookie != kInvalidCookie) {
     asset = assetmanager->OpenNonAsset(asset_path_utf8.c_str(), cookie, Asset::ACCESS_RANDOM);
@@ -566,7 +588,7 @@ static jlong NativeOpenXmlAsset(JNIEnv* env, jobject /*clazz*/, jlong ptr, jint
 
   ATRACE_NAME(base::StringPrintf("AssetManager::OpenXmlAsset(%s)", asset_path_utf8.c_str()).c_str());
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::unique_ptr<Asset> asset;
   if (cookie != kInvalidCookie) {
     asset = assetmanager->OpenNonAsset(asset_path_utf8.c_str(), cookie, Asset::ACCESS_RANDOM);
@@ -614,7 +636,8 @@ static jlong NativeOpenXmlAssetFd(JNIEnv* env, jobject /*clazz*/, jlong ptr, int
   std::unique_ptr<Asset>
       asset(Asset::createFromFd(dup_fd.release(), nullptr, Asset::AccessMode::ACCESS_BUFFER));
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   ApkAssetsCookie cookie = JavaCookieToApkAssetsCookie(jcookie);
 
   const incfs::map_ptr<void> buffer = asset->getIncFsBuffer(true /* aligned */);
@@ -637,8 +660,9 @@ static jlong NativeOpenXmlAssetFd(JNIEnv* env, jobject /*clazz*/, jlong ptr, int
 static jint NativeGetResourceValue(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid,
                                    jshort density, jobject typed_value,
                                    jboolean resolve_references) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   ResourceTimer _timer(ResourceTimer::Counter::GetResourceValue);
+
   auto value = assetmanager->GetResource(static_cast<uint32_t>(resid), false /*may_be_bag*/,
                                          static_cast<uint16_t>(density));
   if (!value.has_value()) {
@@ -656,7 +680,8 @@ static jint NativeGetResourceValue(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
 
 static jint NativeGetResourceBagValue(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid,
                                       jint bag_entry_id, jobject typed_value) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   auto bag = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag.has_value()) {
     return ApkAssetsCookieToJavaCookie(kInvalidCookie);
@@ -683,7 +708,8 @@ static jint NativeGetResourceBagValue(JNIEnv* env, jclass /*clazz*/, jlong ptr,
 }
 
 static jintArray NativeGetStyleAttributes(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
     return nullptr;
@@ -704,7 +730,8 @@ static jintArray NativeGetStyleAttributes(JNIEnv* env, jclass /*clazz*/, jlong p
 
 static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/, jlong ptr,
                                                  jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
     return nullptr;
@@ -725,35 +752,35 @@ static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/,
     }
 
     if (attr_value.type == Res_value::TYPE_STRING) {
-      auto apk_assets_weak = assetmanager->GetApkAssets()[attr_value.cookie];
-      if (auto apk_assets = apk_assets_weak.promote()) {
-        const ResStringPool* pool = apk_assets->GetLoadedArsc()->GetStringPool();
-
-        jstring java_string;
-        if (auto str_utf8 = pool->string8At(attr_value.data); str_utf8.has_value()) {
-          java_string = env->NewStringUTF(str_utf8->data());
-        } else {
-          auto str_utf16 = pool->stringAt(attr_value.data);
-          if (!str_utf16.has_value()) {
-            return nullptr;
+      const auto& apk_assets = assetmanager->GetApkAssets(attr_value.cookie);
+      if (apk_assets) {
+          const ResStringPool* pool = apk_assets->GetLoadedArsc()->GetStringPool();
+
+          jstring java_string;
+          if (auto str_utf8 = pool->string8At(attr_value.data); str_utf8.has_value()) {
+              java_string = env->NewStringUTF(str_utf8->data());
+          } else {
+              auto str_utf16 = pool->stringAt(attr_value.data);
+              if (!str_utf16.has_value()) {
+                  return nullptr;
+              }
+              java_string = env->NewString(reinterpret_cast<const jchar*>(str_utf16->data()),
+                                           str_utf16->size());
           }
-          java_string =
-              env->NewString(reinterpret_cast<const jchar*>(str_utf16->data()), str_utf16->size());
-        }
 
-        // Check for errors creating the strings (if malformed or no memory).
-        if (env->ExceptionCheck()) {
-          return nullptr;
-        }
+          // Check for errors creating the strings (if malformed or no memory).
+          if (env->ExceptionCheck()) {
+              return nullptr;
+          }
 
-        env->SetObjectArrayElement(array, i, java_string);
+          env->SetObjectArrayElement(array, i, java_string);
 
-        // If we have a large amount of string in our array, we might overflow the
-        // local reference table of the VM.
-        env->DeleteLocalRef(java_string);
+          // If we have a large amount of string in our array, we might overflow the
+          // local reference table of the VM.
+          env->DeleteLocalRef(java_string);
       } else {
-        ALOGW("NativeGetResourceStringArray: an expired assets object #%d / %d", i,
-              attr_value.cookie);
+          ALOGW("NativeGetResourceStringArray: an expired assets object #%d / %d", i,
+                attr_value.cookie);
       }
     }
   }
@@ -762,7 +789,8 @@ static jobjectArray NativeGetResourceStringArray(JNIEnv* env, jclass /*clazz*/,
 
 static jintArray NativeGetResourceStringArrayInfo(JNIEnv* env, jclass /*clazz*/, jlong ptr,
                                                   jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
     return nullptr;
@@ -800,7 +828,8 @@ static jintArray NativeGetResourceStringArrayInfo(JNIEnv* env, jclass /*clazz*/,
 }
 
 static jintArray NativeGetResourceIntArray(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
   if (!bag_result.has_value()) {
     return nullptr;
@@ -835,21 +864,22 @@ static jintArray NativeGetResourceIntArray(JNIEnv* env, jclass /*clazz*/, jlong
 }
 
 static jint NativeGetResourceArraySize(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-    ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
-    auto bag = assetmanager->GetBag(static_cast<uint32_t>(resid));
-    if (!bag.has_value()) {
-      return -1;
-    }
+  auto assetmanager = LockAndStartAssetManager(ptr);
+  auto bag = assetmanager->GetBag(static_cast<uint32_t>(resid));
+  if (!bag.has_value()) {
+    return -1;
+  }
     return static_cast<jint>((*bag)->entry_count);
 }
 
 static jint NativeGetResourceArray(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid,
                                    jintArray out_data) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
-  auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
-  if (!bag_result.has_value()) {
+    auto assetmanager = LockAndStartAssetManager(ptr);
+
+    auto bag_result = assetmanager->GetBag(static_cast<uint32_t>(resid));
+    if (!bag_result.has_value()) {
     return -1;
-  }
+    }
 
   const jsize out_data_length = env->GetArrayLength(out_data);
   if (env->ExceptionCheck()) {
@@ -896,7 +926,7 @@ static jint NativeGetResourceArray(JNIEnv* env, jclass /*clazz*/, jlong ptr, jin
 }
 
 static jint NativeGetParentThemeIdentifier(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   const auto parentThemeResId = assetmanager->GetParentThemeResourceId(resid);
   return parentThemeResId.value_or(0);
 }
@@ -923,7 +953,7 @@ static jint NativeGetResourceIdentifier(JNIEnv* env, jclass /*clazz*/, jlong ptr
     package = package_utf8.c_str();
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto resid = assetmanager->GetResourceId(name_utf8.c_str(), type, package);
   if (!resid.has_value()) {
     return 0;
@@ -933,7 +963,7 @@ static jint NativeGetResourceIdentifier(JNIEnv* env, jclass /*clazz*/, jlong ptr
 }
 
 static jstring NativeGetResourceName(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
     return nullptr;
@@ -944,7 +974,7 @@ static jstring NativeGetResourceName(JNIEnv* env, jclass /*clazz*/, jlong ptr, j
 }
 
 static jstring NativeGetResourcePackageName(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
     return nullptr;
@@ -957,7 +987,7 @@ static jstring NativeGetResourcePackageName(JNIEnv* env, jclass /*clazz*/, jlong
 }
 
 static jstring NativeGetResourceTypeName(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
     return nullptr;
@@ -972,7 +1002,7 @@ static jstring NativeGetResourceTypeName(JNIEnv* env, jclass /*clazz*/, jlong pt
 }
 
 static jstring NativeGetResourceEntryName(JNIEnv* env, jclass /*clazz*/, jlong ptr, jint resid) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto name = assetmanager->GetResourceName(static_cast<uint32_t>(resid));
   if (!name.has_value()) {
     return nullptr;
@@ -990,14 +1020,14 @@ static void NativeSetResourceResolutionLoggingEnabled(JNIEnv* /*env*/,
                                                       jclass /*clazz*/,
                                                       jlong ptr,
                                                       jboolean enabled) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   assetmanager->SetResourceResolutionLoggingEnabled(enabled);
 }
 
 static jstring NativeGetLastResourceResolution(JNIEnv* env,
                                                jclass /*clazz*/,
                                                jlong ptr) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::string resolution = assetmanager->GetLastResourceResolution();
   if (resolution.empty()) {
     return nullptr;
@@ -1008,7 +1038,7 @@ static jstring NativeGetLastResourceResolution(JNIEnv* env,
 
 static jobjectArray NativeGetLocales(JNIEnv* env, jclass /*class*/, jlong ptr,
                                      jboolean exclude_system) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   std::set<std::string> locales =
       assetmanager->GetResourceLocales(exclude_system, true /*merge_equivalent_languages*/);
 
@@ -1046,7 +1076,7 @@ static jobject ConstructConfigurationObject(JNIEnv* env, const ResTable_config&
 }
 
 static jobjectArray GetSizeAndUiModeConfigurations(JNIEnv* env, jlong ptr) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   auto configurations = assetmanager->GetResourceConfigurations(true /*exclude_system*/,
                                                                 false /*exclude_mipmap*/);
   if (!configurations.has_value()) {
@@ -1080,12 +1110,10 @@ static jobjectArray NativeGetSizeAndUiModeConfigurations(JNIEnv* env, jclass /*c
   return GetSizeAndUiModeConfigurations(env, ptr);
 }
 
-static jintArray NativeAttributeResolutionStack(
-    JNIEnv* env, jclass /*clazz*/, jlong ptr,
-    jlong theme_ptr, jint xml_style_res,
-    jint def_style_attr, jint def_style_resid) {
-
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+static jintArray NativeAttributeResolutionStack(JNIEnv* env, jclass /*clazz*/, jlong ptr,
+                                                jlong theme_ptr, jint xml_style_res,
+                                                jint def_style_attr, jint def_style_resid) {
+  auto assetmanager = LockAndStartAssetManager(ptr);
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
@@ -1120,7 +1148,7 @@ static jintArray NativeAttributeResolutionStack(
 static void NativeApplyStyle(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong theme_ptr,
                              jint def_style_attr, jint def_style_resid, jlong xml_parser_ptr,
                              jintArray java_attrs, jlong out_values_ptr, jlong out_indices_ptr) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
@@ -1195,7 +1223,7 @@ static jboolean NativeResolveAttrs(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlo
     }
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
@@ -1254,7 +1282,7 @@ static jboolean NativeRetrieveAttributes(JNIEnv* env, jclass /*clazz*/, jlong pt
     }
   }
 
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   ResourceTimer _timer(ResourceTimer::Counter::RetrieveAttributes);
   ResXMLParser* xml_parser = reinterpret_cast<ResXMLParser*>(xml_parser_ptr);
   auto result =
@@ -1272,7 +1300,7 @@ static jboolean NativeRetrieveAttributes(JNIEnv* env, jclass /*clazz*/, jlong pt
 }
 
 static jlong NativeThemeCreate(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   return reinterpret_cast<jlong>(assetmanager->NewTheme().release());
 }
 
@@ -1287,7 +1315,7 @@ static jlong NativeGetThemeFreeFunction(JNIEnv* /*env*/, jclass /*clazz*/) {
 static void NativeThemeApplyStyle(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong theme_ptr,
                                   jint resid, jboolean force) {
   // AssetManager is accessed via the theme, so grab an explicit lock here.
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
@@ -1305,7 +1333,7 @@ static void NativeThemeRebase(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong th
                               jint style_count) {
   // Lock both the original asset manager of the theme and the new asset manager to be used for the
   // theme.
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
 
   uint32_t* style_id_args = nullptr;
   if (style_ids != nullptr) {
@@ -1348,25 +1376,23 @@ static void NativeThemeCopy(JNIEnv* env, jclass /*clazz*/, jlong dst_asset_manag
   Theme* dst_theme = reinterpret_cast<Theme*>(dst_theme_ptr);
   Theme* src_theme = reinterpret_cast<Theme*>(src_theme_ptr);
 
-  ScopedLock<AssetManager2> src_assetmanager(AssetManagerFromLong(src_asset_manager_ptr));
+  auto src_assetmanager = LockAndStartAssetManager(src_asset_manager_ptr);
   CHECK(src_theme->GetAssetManager() == &(*src_assetmanager));
-  (void) src_assetmanager;
 
   if (dst_asset_manager_ptr != src_asset_manager_ptr) {
-    ScopedLock<AssetManager2> dst_assetmanager(AssetManagerFromLong(dst_asset_manager_ptr));
+    auto dst_assetmanager = LockAndStartAssetManager(dst_asset_manager_ptr);
     CHECK(dst_theme->GetAssetManager() == &(*dst_assetmanager));
-    (void) dst_assetmanager;
-
     dst_theme->SetTo(*src_theme);
   } else {
-      dst_theme->SetTo(*src_theme);
+    dst_theme->SetTo(*src_theme);
   }
 }
 
 static jint NativeThemeGetAttributeValue(JNIEnv* env, jclass /*clazz*/, jlong ptr, jlong theme_ptr,
                                          jint resid, jobject typed_value,
                                          jboolean resolve_references) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
+
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
@@ -1389,7 +1415,7 @@ static jint NativeThemeGetAttributeValue(JNIEnv* env, jclass /*clazz*/, jlong pt
 
 static void NativeThemeDump(JNIEnv* /*env*/, jclass /*clazz*/, jlong ptr, jlong theme_ptr,
                             jint priority, jstring tag, jstring prefix) {
-  ScopedLock<AssetManager2> assetmanager(AssetManagerFromLong(ptr));
+  auto assetmanager = LockAndStartAssetManager(ptr);
   Theme* theme = reinterpret_cast<Theme*>(theme_ptr);
   CHECK(theme->GetAssetManager() == &(*assetmanager));
   (void) assetmanager;
diff --git a/libs/androidfw/AssetManager2.cpp b/libs/androidfw/AssetManager2.cpp
index 94dbfb5db1d7..fd5d07f22419 100644
--- a/libs/androidfw/AssetManager2.cpp
+++ b/libs/androidfw/AssetManager2.cpp
@@ -112,7 +112,15 @@ bool AssetManager2::SetApkAssets(std::initializer_list<ApkAssetsPtr> apk_assets,
 }
 
 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 @@ void AssetManager2::BuildDynamicRefTable(ApkAssetsList apk_assets) {
   // 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::BuildDynamicRefTable(ApkAssetsList apk_assets) {
 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 @@ const ResStringPool* AssetManager2::GetStringPoolForCookie(ApkAssetsCookie cooki
   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 @@ const std::unordered_map<std::string, std::string>*
 
 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::GetOverlayablesToString(android::StringPiece package_name,
 }
 
 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 @@ std::set<AssetManager2::ApkAssetsPtr> AssetManager2::GetNonSystemOverlays() cons
     }
 
     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 @@ std::set<AssetManager2::ApkAssetsPtr> AssetManager2::GetNonSystemOverlays() cons
 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 @@ base::expected<std::set<ResTable_config>, IOError> AssetManager2::GetResourceCon
         }
         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 @@ base::expected<std::set<ResTable_config>, IOError> AssetManager2::GetResourceCon
 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 @@ std::set<std::string> AssetManager2::GetResourceLocales(bool exclude_system,
         }
         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<Asset> AssetManager2::Open(const std::string& filename, ApkAsset
 
 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<AssetDir> AssetManager2::OpenDir(const std::string& dirname) con
 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 @@ std::unique_ptr<Asset> AssetManager2::OpenNonAsset(const std::string& filename,
   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 @@ base::expected<FindEntryResult, NullOrIOError> AssetManager2::FindEntry(
     last_resolution_.resid = resid;
   }
 
+  auto op = StartOperation();
+
   // Might use this if density_override != 0.
   ResTable_config density_override_config;
 
@@ -631,7 +656,7 @@ base::expected<FindEntryResult, NullOrIOError> AssetManager2::FindEntry(
 
   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 @@ std::string AssetManager2::GetLastResourceResolution() const {
     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 @@ std::string AssetManager2::GetLastResourceResolution() const {
       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 @@ void AssetManager2::ForEachPackage(base::function_ref<bool(const std::string&, u
   }
 }
 
+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 @@ base::expected<std::monostate, IOError> Theme::SetTo(const Theme& source) {
     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 @@ void Theme::Dump() const {
   }
 }
 
+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 1f979956873f..cedf7326ec95 100644
--- a/libs/androidfw/include/androidfw/AssetManager2.h
+++ b/libs/androidfw/include/androidfw/AssetManager2.h
@@ -102,9 +102,20 @@ class AssetManager2 {
 
   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 @@ class AssetManager2 {
   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 @@ class AssetManager2 {
   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 @@ class AssetManager2 {
   // 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 5a5bafdf829a..df3fa02ce44c 100644
--- a/libs/androidfw/tests/AssetManager2_test.cpp
+++ b/libs/androidfw/tests/AssetManager2_test.cpp
@@ -207,11 +207,11 @@ TEST_F(AssetManager2Test, AssignsOverlayPackageIdLast) {
   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 @@ TEST_F(AssetManager2Test, GetOverlayablesToString) {
             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 568e041ebe5b..60aa7d88925d 100644
--- a/libs/androidfw/tests/Idmap_test.cpp
+++ b/libs/androidfw/tests/Idmap_test.cpp
@@ -66,9 +66,9 @@ class IdmapTest : public ::testing::Test {
 
 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);
 }
 
diff --git a/tools/aapt2/process/SymbolTable.cpp b/tools/aapt2/process/SymbolTable.cpp
index b75458a7b8b6..d78baf9ffeb4 100644
--- a/tools/aapt2/process/SymbolTable.cpp
+++ b/tools/aapt2/process/SymbolTable.cpp
@@ -260,10 +260,11 @@ bool AssetManagerSymbolSource::IsPackageDynamic(uint32_t packageId,
 static std::unique_ptr<SymbolTable::Symbol> LookupAttributeInTable(
     android::AssetManager2& am, ResourceId id) {
   using namespace android;
-  if (am.GetApkAssets().empty()) {
+  if (am.GetApkAssetsCount() == 0) {
     return {};
   }
 
+  auto op = am.StartOperation();
   auto bag_result = am.GetBag(id.id);
   if (!bag_result.has_value()) {
     return nullptr;