Test for ConcurrentGC validity.
Test aims to test for the lost object problem. Should consistently crash incorrect (no dirty card scanning) CMS if the CMS is requested after every allocation.
Change-Id: I6161f0d678067947b60c5fadf57f5bdcb33b6749
diff --git a/build/Android.common.mk b/build/Android.common.mk
index 33c33af..8e0fd51 100644
--- a/build/Android.common.mk
+++ b/build/Android.common.mk
@@ -393,6 +393,7 @@
\
ExceptionTest \
GrowthLimit \
+ ConcurrentGC \
IntMath \
Invoke \
MemUsage \
diff --git a/test/ConcurrentGC/ConcurrentGC.java b/test/ConcurrentGC/ConcurrentGC.java
new file mode 100644
index 0000000..1a0fec8
--- /dev/null
+++ b/test/ConcurrentGC/ConcurrentGC.java
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Map;
+import java.util.Random;
+
+public class ConcurrentGC {
+ private static final int buckets = 16 * 1024;
+ private static final int bufferSize = 1024;
+
+ static class ByteContainer {
+ public byte[] bytes;
+ }
+
+ public static void main(String[] args) throws Exception {
+ try {
+ ByteContainer[] l = new ByteContainer[buckets];
+
+ for (int i = 0; i < buckets; ++i) {
+ l[i] = new ByteContainer();
+ }
+
+ Random rnd = new Random(123456);
+ for (int i = 0; i < buckets / 256; ++i) {
+ int index = rnd.nextInt(buckets);
+ l[index].bytes = new byte[bufferSize];
+
+ // Try to get GC to run if we can
+ Runtime.getRuntime().gc();
+
+ // Shuffle the array to try cause the lost object problem:
+ // This problem occurs when an object is white, it may be
+ // only referenced from a white or grey object. If the white
+ // object is moved during a CMS to be a black object's field, it
+ // causes the moved object to not get marked. This can result in
+ // heap corruption. A typical way to address this issue is by
+ // having a card table.
+ // This aspect of the test is meant to ensure that card
+ // dirtying works and that we check the marked cards after
+ // marking.
+ // If these operations are not done, a segfault / failed assert
+ // should occur.
+ for (int j = 0; j < l.length; ++j) {
+ int a = l.length - i - 1;
+ int b = rnd.nextInt(a);
+ byte[] temp = l[a].bytes;
+ l[a].bytes = l[b].bytes;
+ l[b].bytes = temp;
+ }
+ }
+ } catch (OutOfMemoryError e) {
+ }
+ }
+}