Exempt apps with INSTALL_PACKAGES from freezer

System applications with INSTALL_PACKAGES permission, like store
apps, have long-running processes in order to keep the system stable
and secure. Don't freeze them even if they are cached.

Bug: 184584402
Test: Verified store apps with the permission won't be frozen.

Change-Id: I4ae45a3688ac6d50c0e7d6ef11ce506b283ee82f
Signed-off-by: Li Li <dualli@google.com>

services/core/java/com/android/server/am/CachedAppOptimizer.java

@@ -395,7 +395,7 @@ public final class CachedAppOptimizer {
 
             pw.println("  Tracking last compaction stats for " + mLastCompactionStats.size()
                     + " processes.");
-            pw.println(" " + KEY_USE_FREEZER + "=" + mUseFreezer);
+            pw.println("  " + KEY_USE_FREEZER + "=" + mUseFreezer);
             pw.println("  " + KEY_FREEZER_STATSD_SAMPLE_RATE + "=" + mFreezerStatsdSampleRate);
             pw.println("  " + KEY_FREEZER_DEBOUNCE_TIMEOUT + "=" + mFreezerDebounceTimeout);
             if (DEBUG_COMPACTION) {

services/core/java/com/android/server/am/OomAdjuster.java

@@ -3037,6 +3037,10 @@ public final class OomAdjuster {
             return;
         }
 
+        if (app.mOptRecord.isFreezeExempt()) {
+            return;
+        }
+
         final ProcessCachedOptimizerRecord opt = app.mOptRecord;
         // if an app is already frozen and shouldNotFreeze becomes true, immediately unfreeze
         if (opt.isFrozen() && opt.shouldNotFreeze()) {

services/core/java/com/android/server/am/ProcessCachedOptimizerRecord.java

@@ -80,6 +80,12 @@ final class ProcessCachedOptimizerRecord {
     @GuardedBy("mProcLock")
     private boolean mShouldNotFreeze;
 
+    /**
+     * Exempt from freezer (now for system apps with INSTALL_PACKAGES permission)
+     */
+    @GuardedBy("mProcLock")
+    private boolean mFreezeExempt;
+
     @GuardedBy("mProcLock")
     long getLastCompactTime() {
         return mLastCompactTime;
@@ -160,6 +166,16 @@ final class ProcessCachedOptimizerRecord {
         mShouldNotFreeze = shouldNotFreeze;
     }
 
+    @GuardedBy("mProcLock")
+    boolean isFreezeExempt() {
+        return mFreezeExempt;
+    }
+
+    @GuardedBy("mPreLock")
+    void setFreezeExempt(boolean exempt) {
+        mFreezeExempt = exempt;
+    }
+
     ProcessCachedOptimizerRecord(ProcessRecord app) {
         mApp = app;
         mProcLock = app.mService.mProcLock;
@@ -173,6 +189,7 @@ final class ProcessCachedOptimizerRecord {
     void dump(PrintWriter pw, String prefix, long nowUptime) {
         pw.print(prefix); pw.print("lastCompactTime="); pw.print(mLastCompactTime);
         pw.print(" lastCompactAction="); pw.println(mLastCompactAction);
+        pw.print(prefix); pw.print("isFreezeExempt="); pw.print(mFreezeExempt);
         pw.print(" " + IS_FROZEN + "="); pw.println(mFrozen);
     }
 }

services/core/java/com/android/server/am/ProcessList.java

@@ -54,6 +54,7 @@ import static com.android.server.am.ActivityManagerService.TAG_NETWORK;
 import static com.android.server.am.ActivityManagerService.TAG_PROCESSES;
 import static com.android.server.am.ActivityManagerService.TAG_UID_OBSERVERS;
 
+import android.Manifest;
 import android.annotation.NonNull;
 import android.app.ActivityManager;
 import android.app.ActivityManager.ProcessCapability;
@@ -76,6 +77,7 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.IPackageManager;
+import android.content.pm.PackageManager;
 import android.content.pm.PackageManagerInternal;
 import android.content.res.Resources;
 import android.graphics.Point;
@@ -1774,8 +1776,8 @@ public final class ProcessList {
         checkSlow(startTime, "startProcess: done updating cpu stats");
 
         try {
+            final int userId = UserHandle.getUserId(app.uid);
             try {
-                final int userId = UserHandle.getUserId(app.uid);
                 AppGlobals.getPackageManager().checkPackageStartable(app.info.packageName, userId);
             } catch (RemoteException e) {
                 throw e.rethrowAsRuntimeException();
@@ -1798,6 +1800,12 @@ public final class ProcessList {
                             app.info.packageName);
                     externalStorageAccess = storageManagerInternal.hasExternalStorageAccess(uid,
                             app.info.packageName);
+                    if (pm.checkPermission(Manifest.permission.INSTALL_PACKAGES,
+                            app.info.packageName, userId)
+                            == PackageManager.PERMISSION_GRANTED) {
+                        Slog.i(TAG, app.info.packageName + " is exempt from freezer");
+                        app.mOptRecord.setFreezeExempt(true);
+                    }
                 } catch (RemoteException e) {
                     throw e.rethrowAsRuntimeException();
                 }