Merge "Add new OOM adjustment for the "previous" process." into ics-mr1

Author: Dianne Hackborn

api/current.txt

@@ -14399,6 +14399,7 @@ package android.os {
     field public static final int HONEYCOMB_MR1 = 12; // 0xc
     field public static final int HONEYCOMB_MR2 = 13; // 0xd
     field public static final int ICE_CREAM_SANDWICH = 14; // 0xe
+    field public static final int ICE_CREAM_SANDWICH_MR1 = 15; // 0xf
   }
 
   public final class Bundle implements java.lang.Cloneable android.os.Parcelable {

core/java/android/os/Build.java

@@ -277,7 +277,7 @@ public static class VERSION_CODES {
         public static final int HONEYCOMB_MR2 = 13;
 
         /**
-         * Android 4.0.
+         * October 2011: Android 4.0.
          *
          * <p>Applications targeting this or a later release will get these
          * new changes in behavior:</p>
@@ -309,6 +309,11 @@ public static class VERSION_CODES {
          * </ul>
          */
         public static final int ICE_CREAM_SANDWICH = 14;
+
+        /**
+         * Android 4.1.
+         */
+        public static final int ICE_CREAM_SANDWICH_MR1 = 15;
     }
 
     /** The type of build, like "user" or "eng". */

services/java/com/android/server/am/ActivityManagerService.java

@@ -407,6 +407,12 @@ abstract class ForegroundToken implements IBinder.DeathRecipient {
      */
     ProcessRecord mHomeProcess;
 
+    /**
+     * This is the process holding the activity the user last visited that
+     * is in a different process from the one they are currently in.
+     */
+    ProcessRecord mPreviousProcess;
+    
     /**
      * Packages that the user has asked to have run in screen size
      * compatibility mode instead of filling the screen.
@@ -8114,6 +8120,7 @@ boolean dumpProcessesLocked(FileDescriptor fd, PrintWriter pw, String[] args,
 
         pw.println();
         pw.println("  mHomeProcess: " + mHomeProcess);
+        pw.println("  mPreviousProcess: " + mPreviousProcess);
         if (mHeavyWeightProcess != null) {
             pw.println("  mHeavyWeightProcess: " + mHeavyWeightProcess);
         }
@@ -8212,6 +8219,7 @@ boolean dumpOomLocked(FileDescriptor fd, PrintWriter pw, String[] args,
             pw.print("    BACKUP_APP_ADJ: "); pw.println(ProcessList.BACKUP_APP_ADJ);
             pw.print("    SERVICE_ADJ: "); pw.println(ProcessList.SERVICE_ADJ);
             pw.print("    HOME_APP_ADJ: "); pw.println(ProcessList.HOME_APP_ADJ);
+            pw.print("    PREVIOUS_APP_ADJ: "); pw.println(ProcessList.PREVIOUS_APP_ADJ);
             pw.print("    SERVICE_B_ADJ: "); pw.println(ProcessList.SERVICE_B_ADJ);
             pw.print("    HIDDEN_APP_MIN_ADJ: "); pw.println(ProcessList.HIDDEN_APP_MIN_ADJ);
             pw.print("    HIDDEN_APP_MAX_ADJ: "); pw.println(ProcessList.HIDDEN_APP_MAX_ADJ);
@@ -8228,6 +8236,7 @@ boolean dumpOomLocked(FileDescriptor fd, PrintWriter pw, String[] args,
 
         pw.println();
         pw.println("  mHomeProcess: " + mHomeProcess);
+        pw.println("  mPreviousProcess: " + mPreviousProcess);
         if (mHeavyWeightProcess != null) {
             pw.println("  mHeavyWeightProcess: " + mHeavyWeightProcess);
         }
@@ -9009,6 +9018,8 @@ public int compare(Pair<ProcessRecord, Integer> object1,
                 oomAdj = buildOomTag("bak", "  ", r.setAdj, ProcessList.HIDDEN_APP_MIN_ADJ);
             } else if (r.setAdj >= ProcessList.SERVICE_B_ADJ) {
                 oomAdj = buildOomTag("svcb ", null, r.setAdj, ProcessList.SERVICE_B_ADJ);
+            } else if (r.setAdj >= ProcessList.PREVIOUS_APP_ADJ) {
+                oomAdj = buildOomTag("prev ", null, r.setAdj, ProcessList.PREVIOUS_APP_ADJ);
             } else if (r.setAdj >= ProcessList.HOME_APP_ADJ) {
                 oomAdj = buildOomTag("home ", null, r.setAdj, ProcessList.HOME_APP_ADJ);
             } else if (r.setAdj >= ProcessList.SERVICE_ADJ) {
@@ -9287,12 +9298,13 @@ final void dumpApplicationMemoryUsage(FileDescriptor fd,
             ProcessList.SYSTEM_ADJ, ProcessList.PERSISTENT_PROC_ADJ, ProcessList.FOREGROUND_APP_ADJ,
             ProcessList.VISIBLE_APP_ADJ, ProcessList.PERCEPTIBLE_APP_ADJ, ProcessList.HEAVY_WEIGHT_APP_ADJ,
             ProcessList.BACKUP_APP_ADJ, ProcessList.SERVICE_ADJ, ProcessList.HOME_APP_ADJ,
-            ProcessList.SERVICE_B_ADJ, ProcessList.HIDDEN_APP_MAX_ADJ
+            ProcessList.PREVIOUS_APP_ADJ, ProcessList.SERVICE_B_ADJ, ProcessList.HIDDEN_APP_MAX_ADJ
         };
         final String[] oomLabel = new String[] {
                 "System", "Persistent", "Foreground",
                 "Visible", "Perceptible", "Heavy Weight",
-                "Backup", "A Services", "Home", "B Services", "Background"
+                "Backup", "A Services", "Home", "Previous",
+                "B Services", "Background"
         };
         long oomPss[] = new long[oomLabel.length];
         ArrayList<MemItem>[] oomProcs = (ArrayList<MemItem>[])new ArrayList[oomLabel.length];
@@ -9714,7 +9726,10 @@ private final void cleanUpApplicationRecordLocked(ProcessRecord app,
         if (app == mHomeProcess) {
             mHomeProcess = null;
         }
-        
+        if (app == mPreviousProcess) {
+            mPreviousProcess = null;
+        }
+
         if (restart) {
             // We have components that still need to be running in the
             // process, so re-launch it.
@@ -13112,6 +13127,17 @@ private final int computeOomAdjLocked(ProcessRecord app, int hiddenAdj,
             app.adjType = "home";
         }
 
+        if (adj > ProcessList.PREVIOUS_APP_ADJ && app == mPreviousProcess
+                && app.activities.size() > 0) {
+            // This was the previous process that showed UI to the user.
+            // We want to try to keep it around more aggressively, to give
+            // a good experience around switching between two apps.
+            adj = ProcessList.PREVIOUS_APP_ADJ;
+            schedGroup = Process.THREAD_GROUP_BG_NONINTERACTIVE;
+            app.hidden = false;
+            app.adjType = "previous";
+        }
+
         if (false) Slog.i(TAG, "OOM " + app + ": initial adj=" + adj
                 + " reason=" + app.adjType);
 
@@ -13841,7 +13867,8 @@ final void updateOomAdjLocked() {
                     } else {
                         numBg++;
                     }
-                } else if (app.curAdj >= ProcessList.HOME_APP_ADJ) {
+                } else if (app.curAdj >= ProcessList.HOME_APP_ADJ
+                        && app.curAdj != ProcessList.SERVICE_B_ADJ) {
                     numBg++;
                 }
             }

services/java/com/android/server/am/ActivityStack.java

@@ -1363,6 +1363,13 @@ final boolean resumeTopActivityLocked(ActivityRecord prev) {
                         + ", nowVisible=" + next.nowVisible);
                 }
             }
+
+            if (!prev.finishing && prev.app != null && prev.app != next.app) {
+                // We are switching to a new activity that is in a different
+                // process than the previous one.  Note the previous process,
+                // so we can try to keep it around.
+                mService.mPreviousProcess = prev.app;
+            }
         }
 
         // Launching this app's activity, make sure the app is no longer

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

@@ -38,11 +38,19 @@ class ProcessList {
     // This is a process only hosting activities that are not visible,
     // so it can be killed without any disruption.
     static final int HIDDEN_APP_MAX_ADJ = 15;
-    static int HIDDEN_APP_MIN_ADJ = 8;
+    static int HIDDEN_APP_MIN_ADJ = 9;
 
     // The B list of SERVICE_ADJ -- these are the old and decrepit
     // services that aren't as shiny and interesting as the ones in the A list.
-    static final int SERVICE_B_ADJ = 7;
+    static final int SERVICE_B_ADJ = 8;
+
+    // This is the process of the previous application that the user was in.
+    // This process is kept above other things, because it is very common to
+    // switch back to the previous app.  This is important both for recent
+    // task switch (toggling between the two top recent apps) as well as normal
+    // UI flow such as clicking on a URI in the e-mail app to view in the browser,
+    // and then pressing back to return to e-mail.
+    static final int PREVIOUS_APP_ADJ = 7;
 
     // This is a process holding the home application -- we want to try
     // avoiding killing it, even if it would normally be in the background,