From 057f4cb871af93d9bcd1ca5213bc4821e626ec6e Mon Sep 17 00:00:00 2001
From: Jing Ji <jji@google.com>
Date: Fri, 1 Nov 2019 13:23:11 -0700
Subject: [PATCH] Process adj could stay at UNKNOWN_ADJ till next full adj
 update

Fix an issue that a non-cached process goes to cached state, but
there is no other connections to this app, its adj value could
be UNKNOWN_ADJ, till the next full adj update occurs.

Bug: 135941673
Test: atest MockingOomAdjusterTests
Change-Id: I397b26c0b4c2b84a8c418cc21f6e0c85950e39e7
---
 .../java/com/android/server/am/OomAdjuster.java  | 12 +++++++++---
 .../server/am/MockingOomAdjusterTests.java       | 16 ++++++++++++++++
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/am/OomAdjuster.java b/services/core/java/com/android/server/am/OomAdjuster.java
index f610d7d63b6c6..30674db484d5c 100644
--- a/services/core/java/com/android/server/am/OomAdjuster.java
+++ b/services/core/java/com/android/server/am/OomAdjuster.java
@@ -410,6 +410,13 @@ public final class OomAdjuster {
             mAdjSeq--;
             // Update these reachable processes
             updateOomAdjLockedInner(oomAdjReason, topApp, processes, uids, false);
+        } else if (app.getCurRawAdj() == ProcessList.UNKNOWN_ADJ) {
+            // In case the app goes from non-cached to cached but it doesn't have other reachable
+            // processes, its adj could be still unknown as of now, assign one.
+            processes.add(app);
+            assignCachedAdjIfNecessary(processes);
+            applyOomAdjLocked(app, false, SystemClock.uptimeMillis(),
+                    SystemClock.elapsedRealtime());
         }
         mService.mOomAdjProfiler.oomAdjEnded();
         Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
@@ -490,7 +497,7 @@ public final class OomAdjuster {
             }
         }
 
-        assignCachedAdjIfNecessary();
+        assignCachedAdjIfNecessary(mProcessList.mLruProcesses);
 
         if (fullUpdate) { // There won't be cycles if we didn't compute clients above.
             // Cycle strategy:
@@ -564,8 +571,7 @@ public final class OomAdjuster {
         }
     }
 
-    private void assignCachedAdjIfNecessary() {
-        ArrayList<ProcessRecord> lruList = mProcessList.mLruProcesses;
+    private void assignCachedAdjIfNecessary(ArrayList<ProcessRecord> lruList) {
         final int numLru = lruList.size();
 
         // First update the OOM adjustment for each of the
diff --git a/services/tests/mockingservicestests/src/com/android/server/am/MockingOomAdjusterTests.java b/services/tests/mockingservicestests/src/com/android/server/am/MockingOomAdjusterTests.java
index 57f55e32a3814..e7f6a7484881c 100644
--- a/services/tests/mockingservicestests/src/com/android/server/am/MockingOomAdjusterTests.java
+++ b/services/tests/mockingservicestests/src/com/android/server/am/MockingOomAdjusterTests.java
@@ -61,6 +61,7 @@ import static com.android.server.am.ProcessList.UNKNOWN_ADJ;
 import static com.android.server.am.ProcessList.VISIBLE_APP_ADJ;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.AdditionalAnswers.answer;
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.anyInt;
@@ -540,6 +541,21 @@ public class MockingOomAdjusterTests {
                 SCHED_GROUP_DEFAULT);
     }
 
+    @SuppressWarnings("GuardedBy")
+    @Test
+    public void testUpdateOomAdj_DoOne_NonCachedToCached() {
+        ProcessRecord app = spy(makeDefaultProcessRecord(MOCKAPP_PID, MOCKAPP_UID,
+                MOCKAPP_PROCESSNAME, MOCKAPP_PACKAGENAME, false));
+        app.cached = false;
+        app.setCurRawAdj(SERVICE_ADJ);
+        doReturn(null).when(sService).getTopAppLocked();
+        sService.mWakefulness = PowerManagerInternal.WAKEFULNESS_AWAKE;
+        sService.mOomAdjuster.updateOomAdjLocked(app, OomAdjuster.OOM_ADJ_REASON_NONE);
+
+        assertTrue(ProcessList.CACHED_APP_MIN_ADJ <= app.setAdj);
+        assertTrue(ProcessList.CACHED_APP_MAX_ADJ >= app.setAdj);
+    }
+
     @SuppressWarnings("GuardedBy")
     @Test
     public void testUpdateOomAdj_DoOne_Service_Started() {