Scan the downstream apps while updating oomadj for pending records

Bug: 188060432
Test: atest ActivityManagerFgsBgStartTest
Test: atest FrameworksServicesTests:ActivityManagerTest
Test: atest MockingOomAdjusterTests
Test: atest CtsAppTestCases:ActivityManagerProcessStateTest
Change-Id: I8f2574d7cc6a59c76452f7cce57dab1b633fa7f5

1 files changed, 53 insertions, 34 deletions

diff --git a/services/core/java/com/android/server/am/OomAdjuster.java b/services/core/java/com/android/server/am/OomAdjuster.java
index 01bbb039fdba..1e041545c6be 100644
--- a/services/core/java/com/android/server/am/OomAdjuster.java
+++ b/services/core/java/com/android/server/am/OomAdjuster.java
@@ -511,6 +511,7 @@ public class OomAdjuster {
         final ProcessRecord topApp = mService.getTopApp();
         final ProcessStateRecord state = app.mState;
         final boolean wasCached = state.isCached();
+        final int oldCap = state.getSetCapability();
 
         mAdjSeq++;
 
@@ -526,6 +527,7 @@ public class OomAdjuster {
                 SystemClock.uptimeMillis());
         if (oomAdjAll
                 && (wasCached != state.isCached()
+                    || oldCap != state.getSetCapability()
                     || state.getCurRawAdj() == ProcessList.UNKNOWN_ADJ)) {
             // Changed to/from cached state, so apps after it in the LRU
             // list may also be changed.
@@ -663,6 +665,7 @@ public class OomAdjuster {
                 ? oldAdj : ProcessList.UNKNOWN_ADJ;
         final boolean wasBackground = ActivityManager.isProcStateBackground(
                 state.getSetProcState());
+        final int oldCap = state.getSetCapability();
         state.setContainsCycle(false);
         state.setProcStateChanged(false);
         state.resetCachedInfo();
@@ -671,6 +674,7 @@ public class OomAdjuster {
         boolean success = performUpdateOomAdjLSP(app, cachedAdj, topApp, false,
                 SystemClock.uptimeMillis());
         if (!success || (wasCached == state.isCached() && oldAdj != ProcessList.INVALID_ADJ
+                && oldCap == state.getCurCapability()
                 && wasBackground == ActivityManager.isProcStateBackground(
                         state.getSetProcState()))) {
             // Okay, it's unchanged, it won't impact any service it binds to, we're done here.
@@ -685,20 +689,60 @@ public class OomAdjuster {
         // Next to find out all its reachable processes
         ArrayList<ProcessRecord> processes = mTmpProcessList;
         ActiveUids uids = mTmpUidRecords;
-        ArrayDeque<ProcessRecord> queue = mTmpQueue;
+        mPendingProcessSet.add(app);
 
+        boolean containsCycle = collectReachableProcessesLocked(mPendingProcessSet,
+                processes, uids);
+
+        // Reset the flag
+        state.setReachable(false);
+        // Remove this app from the return list because we've done the computation on it.
+        processes.remove(app);
+
+        int size = processes.size();
+        if (size > 0) {
+            mAdjSeq--;
+            // Update these reachable processes
+            updateOomAdjInnerLSP(oomAdjReason, topApp, processes, uids, containsCycle, false);
+        } else if (state.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);
+            applyOomAdjLSP(app, false, SystemClock.uptimeMillis(),
+                    SystemClock.elapsedRealtime());
+        }
+        mTmpProcessList.clear();
+        mService.mOomAdjProfiler.oomAdjEnded();
+        Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
+        return true;
+    }
+
+    @GuardedBy("mService")
+    private boolean collectReachableProcessesLocked(ArraySet<ProcessRecord> apps,
+            ArrayList<ProcessRecord> processes, ActiveUids uids) {
+        final ArrayDeque<ProcessRecord> queue = mTmpQueue;
+        queue.clear();
+        for (int i = 0, size = apps.size(); i < size; i++) {
+            final ProcessRecord app = apps.valueAt(i);
+            app.mState.setReachable(true);
+            queue.offer(app);
+        }
+
+        return collectReachableProcessesLocked(queue, processes, uids);
+    }
+
+    @GuardedBy("mService")
+    private boolean collectReachableProcessesLocked(ArrayDeque<ProcessRecord> queue,
+            ArrayList<ProcessRecord> processes, ActiveUids uids) {
         processes.clear();
         uids.clear();
-        queue.clear();
 
         // Track if any of them reachables could include a cycle
         boolean containsCycle = false;
         // Scan downstreams of the process record
-        state.setReachable(true);
-        for (ProcessRecord pr = app; pr != null; pr = queue.poll()) {
-            if (pr != app) {
-                processes.add(pr);
-            }
+        for (ProcessRecord pr = queue.poll(); pr != null; pr = queue.poll()) {
+            processes.add(pr);
             final UidRecord uidRec = pr.getUidRecord();
             if (uidRec != null) {
                 uids.put(uidRec.getUid(), uidRec);
@@ -749,8 +793,6 @@ public class OomAdjuster {
             }
         }
 
-        // Reset the flag
-        state.setReachable(false);
         int size = processes.size();
         if (size > 0) {
             // Reverse the process list, since the updateOomAdjInnerLSP scans from the end of it.
@@ -759,21 +801,8 @@ public class OomAdjuster {
                 processes.set(l, processes.get(r));
                 processes.set(r, t);
             }
-            mAdjSeq--;
-            // Update these reachable processes
-            updateOomAdjInnerLSP(oomAdjReason, topApp, processes, uids, containsCycle, false);
-        } else if (state.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);
-            applyOomAdjLSP(app, false, SystemClock.uptimeMillis(),
-                    SystemClock.elapsedRealtime());
         }
-        mTmpProcessList.clear();
-        mService.mOomAdjProfiler.oomAdjEnded();
-        Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
-        return true;
+        return containsCycle;
     }
 
     /**
@@ -857,18 +886,8 @@ public class OomAdjuster {
 
         final ArrayList<ProcessRecord> processes = mTmpProcessList;
         final ActiveUids uids = mTmpUidRecords;
+        collectReachableProcessesLocked(mPendingProcessSet, processes, uids);
         synchronized (mProcLock) {
-            uids.clear();
-            processes.clear();
-            for (int i = mPendingProcessSet.size() - 1; i >= 0; i--) {
-                final ProcessRecord app = mPendingProcessSet.valueAt(i);
-                final UidRecord uidRec = app.getUidRecord();
-                if (uidRec != null) {
-                    uids.put(uidRec.getUid(), uidRec);
-                }
-                processes.add(app);
-            }
-
             updateOomAdjInnerLSP(oomAdjReason, topApp, processes, uids, true, false);
         }
         processes.clear();