Log storage savings info with the GlobalHibernatedApps atom

Retrieve the number of freed bytes from PM and store it in
GlobalLevelState when a package is globally hibernated. Reset the value
when it gets unhibernated and write it to disk to persist across device
reboot.

Bug: 188819665
Test: atest AppHibernationServiceTest
Change-Id: I187ec803776cc76c77a660e1ba2f72c2e77765f9

6 files changed, 32 insertions, 6 deletions

diff --git a/core/proto/android/server/apphibernationservice.proto b/core/proto/android/server/apphibernationservice.proto
index d341c4b2f0a8..64c2a322548f 100644
--- a/core/proto/android/server/apphibernationservice.proto
+++ b/core/proto/android/server/apphibernationservice.proto
@@ -39,4 +39,5 @@ message GlobalLevelHibernationStatesProto {
 message GlobalLevelHibernationStateProto {
   optional string package_name = 1;
   optional bool hibernated = 2;
+  optional int64 saved_byte = 3;
 }
\ No newline at end of file
diff --git a/services/core/java/android/content/pm/PackageManagerInternal.java b/services/core/java/android/content/pm/PackageManagerInternal.java
index 92996241a3a6..f7ddd2922b25 100644
--- a/services/core/java/android/content/pm/PackageManagerInternal.java
+++ b/services/core/java/android/content/pm/PackageManagerInternal.java
@@ -1151,6 +1151,8 @@ public abstract class PackageManagerInternal implements PackageSettingsSnapshotP
 
     /**
      * Deletes the OAT artifacts of a package.
+     * @param packageName a specific package
+     * @return the number of freed bytes or -1 if there was an error in the process.
      */
-    public abstract void deleteOatArtifactsOfPackage(String packageName);
+    public abstract long deleteOatArtifactsOfPackage(String packageName);
 }
diff --git a/services/core/java/com/android/server/apphibernation/AppHibernationService.java b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
index 4cb2e9b5cb97..7f1402d83a0c 100644
--- a/services/core/java/com/android/server/apphibernation/AppHibernationService.java
+++ b/services/core/java/com/android/server/apphibernation/AppHibernationService.java
@@ -456,7 +456,9 @@ public final class AppHibernationService extends SystemService {
     private void hibernatePackageGlobally(@NonNull String packageName, GlobalLevelState state) {
         Trace.traceBegin(Trace.TRACE_TAG_SYSTEM_SERVER, "hibernatePackageGlobally");
         if (mOatArtifactDeletionEnabled) {
-            mPackageManagerInternal.deleteOatArtifactsOfPackage(packageName);
+            state.savedByte = Math.max(
+                    mPackageManagerInternal.deleteOatArtifactsOfPackage(packageName),
+                    0);
         }
         state.hibernated = true;
         Trace.traceEnd(Trace.TRACE_TAG_SYSTEM_SERVER);
@@ -469,6 +471,7 @@ public final class AppHibernationService extends SystemService {
     private void unhibernatePackageGlobally(@NonNull String packageName, GlobalLevelState state) {
         Trace.traceBegin(Trace.TRACE_TAG_SYSTEM_SERVER, "unhibernatePackageGlobally");
         state.hibernated = false;
+        state.savedByte = 0;
         state.lastUnhibernatedMs = System.currentTimeMillis();
         Trace.traceEnd(Trace.TRACE_TAG_SYSTEM_SERVER);
     }
@@ -943,6 +946,9 @@ public final class AppHibernationService extends SystemService {
     }
 
     private final class StatsPullAtomCallbackImpl implements StatsPullAtomCallback {
+
+        private static final int MEGABYTE_IN_BYTES = 1000000;
+
         @Override
         public int onPullAtom(int atomTag, @NonNull List<StatsEvent> data) {
             if (!isAppHibernationEnabled()
@@ -969,12 +975,21 @@ public final class AppHibernationService extends SystemService {
                     break;
                 case FrameworkStatsLog.GLOBAL_HIBERNATED_APPS:
                     int hibernatedAppCount = 0;
+                    long storage_saved_byte = 0;
                     synchronized (mLock) {
                         for (GlobalLevelState state : mGlobalHibernationStates.values()) {
-                            if (state.hibernated) hibernatedAppCount++;
+                            if (state.hibernated) {
+                                hibernatedAppCount++;
+                                storage_saved_byte += state.savedByte;
+                            }
                         }
                     }
-                    data.add(FrameworkStatsLog.buildStatsEvent(atomTag, hibernatedAppCount));
+                    data.add(
+                            FrameworkStatsLog.buildStatsEvent(
+                                    atomTag,
+                                    hibernatedAppCount,
+                                    storage_saved_byte / MEGABYTE_IN_BYTES)
+                    );
                     break;
                 default:
                     return StatsManager.PULL_SKIP;
diff --git a/services/core/java/com/android/server/apphibernation/GlobalLevelHibernationProto.java b/services/core/java/com/android/server/apphibernation/GlobalLevelHibernationProto.java
index 79e995b038fa..018d6023f083 100644
--- a/services/core/java/com/android/server/apphibernation/GlobalLevelHibernationProto.java
+++ b/services/core/java/com/android/server/apphibernation/GlobalLevelHibernationProto.java
@@ -41,6 +41,7 @@ final class GlobalLevelHibernationProto implements ProtoReadWriter<List<GlobalLe
             GlobalLevelState state = data.get(i);
             stream.write(GlobalLevelHibernationStateProto.PACKAGE_NAME, state.packageName);
             stream.write(GlobalLevelHibernationStateProto.HIBERNATED, state.hibernated);
+            stream.write(GlobalLevelHibernationStateProto.SAVED_BYTE, state.savedByte);
             stream.end(token);
         }
     }
@@ -66,6 +67,10 @@ final class GlobalLevelHibernationProto implements ProtoReadWriter<List<GlobalLe
                         state.hibernated =
                                 stream.readBoolean(GlobalLevelHibernationStateProto.HIBERNATED);
                         break;
+                    case (int) GlobalLevelHibernationStateProto.SAVED_BYTE:
+                        state.savedByte =
+                                stream.readLong(GlobalLevelHibernationStateProto.SAVED_BYTE);
+                        break;
                     default:
                         Slog.w(TAG, "Undefined field in proto: " + stream.getFieldNumber());
                 }
diff --git a/services/core/java/com/android/server/apphibernation/GlobalLevelState.java b/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
index f4433a7fa5f6..104ecbc17d8a 100644
--- a/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
+++ b/services/core/java/com/android/server/apphibernation/GlobalLevelState.java
@@ -29,6 +29,8 @@ final class GlobalLevelState {
 
     public String packageName;
     public boolean hibernated;
+    // The number of saved bytes from the current hibernation. It will be 0 if not in hibernation.
+    public long savedByte;
     @CurrentTimeMillisLong
     public long lastUnhibernatedMs;
 
@@ -37,6 +39,7 @@ final class GlobalLevelState {
         return "GlobalLevelState{"
                 + "packageName='" + packageName + '\''
                 + ", hibernated=" + hibernated + '\''
+                + ", savedByte=" + savedByte + '\''
                 + ", lastUnhibernated=" + DATE_FORMAT.format(lastUnhibernatedMs)
                 + '}';
     }
diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index 364ac42985f1..7ff836940dce 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -28043,8 +28043,8 @@ public class PackageManagerService extends IPackageManager.Stub
         }
 
         @Override
-        public void deleteOatArtifactsOfPackage(String packageName) {
-            PackageManagerService.this.deleteOatArtifactsOfPackage(packageName);
+        public long deleteOatArtifactsOfPackage(String packageName) {
+            return PackageManagerService.this.deleteOatArtifactsOfPackage(packageName);
         }
 
         @Override