BinderCallsStats - add debug entries to output

Test: UT and manually verified that debug entries are included in
adb shell dumpsys binder_stats

Change-Id: If6a64f7ac14d12323d0cb855b7603eb259e19630

core/java/com/android/internal/os/BinderCallsStats.java

@@ -19,6 +19,7 @@ package com.android.internal.os;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.os.Binder;
+import android.os.Process;
 import android.os.SystemClock;
 import android.os.UserHandle;
 import android.text.format.DateFormat;
@@ -78,6 +79,7 @@ public class BinderCallsStats implements BinderInternal.Observer {
     private final Random mRandom;
     private long mStartTime = System.currentTimeMillis();
     private long mCallStatsCount = 0;
+    private boolean mAddDebugEntries = false;
 
     private CachedDeviceState.Readonly mDeviceState;
 
@@ -317,9 +319,28 @@ public class BinderCallsStats implements BinderInternal.Observer {
             exported.methodName = methodName;
         }
 
+        // Debug entries added to help validate the data.
+        if (mAddDebugEntries) {
+            resultCallStats.add(createDebugEntry("start_time_millis", mStartTime));
+            resultCallStats.add(createDebugEntry("end_time_millis", System.currentTimeMillis()));
+        }
+
         return resultCallStats;
     }
 
+    private ExportedCallStat createDebugEntry(String variableName, long value) {
+        final int uid = Process.myUid();
+        final ExportedCallStat callStat = new ExportedCallStat();
+        callStat.className = "";
+        callStat.workSourceUid = uid;
+        callStat.callingUid = uid;
+        callStat.recordedCallCount = 1;
+        callStat.callCount = 1;
+        callStat.methodName = "__DEBUG_" + variableName;
+        callStat.maxReplySizeBytes = value;
+        return callStat;
+    }
+
     /** @hide */
     public ArrayMap<String, Integer> getExportedExceptionStats() {
         synchronized (mLock) {
@@ -457,6 +478,10 @@ public class BinderCallsStats implements BinderInternal.Observer {
         }
     }
 
+    public void setAddDebugEntries(boolean addDebugEntries) {
+        mAddDebugEntries = addDebugEntries;
+    }
+
     /**
      * Sets the maximum number of items to track.
      */

core/tests/coretests/src/com/android/internal/os/BinderCallsStatsTest.java

@@ -17,6 +17,7 @@
 package com.android.internal.os;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 import android.os.Binder;
 import android.platform.test.annotations.Presubmit;
@@ -613,6 +614,23 @@ public class BinderCallsStatsTest {
         assertEquals(CALLING_UID, callStats.callingUid);
     }
 
+    @Test
+    public void testAddsDebugEntries() {
+        long startTime = System.currentTimeMillis();
+        TestBinderCallsStats bcs = new TestBinderCallsStats();
+        bcs.setAddDebugEntries(true);
+        ArrayList<BinderCallsStats.ExportedCallStat> callStats = bcs.getExportedCallStats();
+        assertEquals(2, callStats.size());
+        BinderCallsStats.ExportedCallStat debugEntry1 = callStats.get(0);
+        assertEquals("", debugEntry1.className);
+        assertEquals("__DEBUG_start_time_millis", debugEntry1.methodName);
+        assertTrue(startTime <= debugEntry1.maxReplySizeBytes);
+        BinderCallsStats.ExportedCallStat debugEntry2 = callStats.get(1);
+        assertEquals("", debugEntry2.className);
+        assertEquals("__DEBUG_end_time_millis", debugEntry2.methodName);
+        assertTrue(debugEntry1.maxReplySizeBytes <= debugEntry2.maxReplySizeBytes);
+    }
+
     class TestBinderCallsStats extends BinderCallsStats {
         public int callingUid = CALLING_UID;
         public int workSourceUid = WORKSOURCE_UID;
@@ -634,6 +652,7 @@ public class BinderCallsStatsTest {
             });
             setSamplingInterval(1);
             setDeviceState(mDeviceState.getReadonlyClient());
+            setAddDebugEntries(false);
         }
 
         @Override

services/core/java/com/android/server/BinderCallsStatsService.java

@@ -116,6 +116,7 @@ public class BinderCallsStatsService extends Binder {
                 }
                 mEnabled = enabled;
                 mBinderCallsStats.reset();
+                mBinderCallsStats.setAddDebugEntries(enabled);
             }
         }
     }