8132718: Add tests which check that when humongous classloader object becomes unreachable it and all classes that were loaded in it should be collected
Reviewed-by: jmasa, dfazunen
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/gc/g1/humongousObjects/ClassLoaderGenerator.java Thu Apr 21 17:55:14 2016 +0300
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+package gc.g1.humongousObjects;
+
+import gc.testlibrary.Helpers;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+/**
+ * Generates non-humongous and humongous class loaders.
+ * Since the generation depends on current host architecture it cannot be done as part of pre-compilation step
+ */
+public class ClassLoaderGenerator {
+ public static void main(String[] args) throws IOException {
+
+ if (args.length != 1) {
+ throw new Error("Test Bug: Expected region size wasn't provided as command line argument");
+ }
+
+ long regionSize = Long.parseLong(args[0]) * 1024 * 1024;
+
+ Path wrkDir = Paths.get("");
+ generateClassLoader(regionSize, wrkDir);
+
+ }
+
+ public static void generateClassLoader(long regionSize, Path wrkDir) throws IOException {
+ // Generating simple classloader
+ String finalSimpleClassLoaderPrototype = TestHumongousClassLoader.GENERIC_PROTOTYPE
+ .replace("${Methods}",
+ TestHumongousClassLoader.LOAD_CLASS_METHOD_PROTOTYPE
+ .replace("${ClassLoadFilter}",
+ "fileName.equals(\"" + TestHumongousClassLoader.HUMONGOUS_CLASSLOADER_NAME
+ + "\")"))
+ .replace("${ClassHeader}", TestHumongousClassLoader.CLASS_HEADER)
+ .replace("${ConstructorClause}", TestHumongousClassLoader.CONSTUCTOR_PROTOTYPE);
+
+ Helpers.generateByTemplateAndCompile(TestHumongousClassLoader.SIMPLE_CLASSLOADER_NAME, "ClassLoader",
+ finalSimpleClassLoaderPrototype, TestHumongousClassLoader.CONSTUCTOR_PROTOTYPE, regionSize / 4,
+ wrkDir, TestHumongousClassLoader.SIMPLE_CLASSLOADER_NAME + "Base");
+
+
+ // Preparations for generating humongous classloader
+
+ // Generating condition for loadClass method of generated class loader
+ // We want the generated class loader to load only classes from G1SampleClass enum
+ // All other classes should be loaded by parent classloader
+ // As result we get full loadClass method
+ StringBuilder classesToLoadBuilder = new StringBuilder();
+ for (G1SampleClass g1SampleClass : G1SampleClass.values()) {
+ if (classesToLoadBuilder.length() != 0) {
+ classesToLoadBuilder.append(" || ");
+ }
+ classesToLoadBuilder.append("fileName.startsWith(\"" + Helpers.enumNameToClassName(g1SampleClass.name())
+ + "\")");
+ }
+
+ // Generating final class loader prototype - with specified methods,header and constructor
+ String finalHumongousClassLoaderPrototype = TestHumongousClassLoader.GENERIC_PROTOTYPE
+ .replace("${Methods}",
+ TestHumongousClassLoader.LOAD_CLASS_METHOD_PROTOTYPE
+ .replace("${ClassLoadFilter}", classesToLoadBuilder))
+ .replace("${ClassHeader}", TestHumongousClassLoader.CLASS_HEADER)
+ .replace("${ConstructorClause}", TestHumongousClassLoader.CONSTUCTOR_PROTOTYPE);
+
+
+ // Generating humongous classloader with specified name, base class, final class prototype and
+ // constructor prototype for filler classes
+ // Generated class instance should be humongous since we specify size of (regionSize * 3 / 4)
+ Helpers.generateByTemplateAndCompile(TestHumongousClassLoader.HUMONGOUS_CLASSLOADER_NAME, "ClassLoader",
+ finalHumongousClassLoaderPrototype, TestHumongousClassLoader.CONSTUCTOR_PROTOTYPE,
+ regionSize * 3 / 4,
+ wrkDir, TestHumongousClassLoader.HUMONGOUS_CLASSLOADER_NAME + "Base");
+
+
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/gc/g1/humongousObjects/TestHumongousClassLoader.java Thu Apr 21 17:55:14 2016 +0300
@@ -0,0 +1,220 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+package gc.g1.humongousObjects;
+
+import gc.testlibrary.Helpers;
+import jdk.test.lib.Asserts;
+import sun.hotspot.WhiteBox;
+
+import java.io.IOException;
+import java.lang.reflect.InvocationTargetException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+/**
+ * @test gc.g1.humongousObjects.TestHumongousClassLoader
+ * @summary Checks that unreachable classes and unreachable humongous class loader are unloaded after GC
+ * @requires vm.gc=="G1" | vm.gc=="null"
+ * @requires vm.opt.G1HeapRegionSize == "null" | vm.opt.G1HeapRegionSize == "1M"
+ * @library /testlibrary /test/lib /
+ * @modules java.management
+ * @build sun.hotspot.WhiteBox
+ * gc.testlibrary.Helpers
+ * gc.g1.humongousObjects.G1SampleClass
+ * gc.g1.humongousObjects.ClassLoaderGenerator
+ * gc.g1.humongousObjects.TestHumongousClassLoader
+ *
+ * @run driver ClassFileInstaller sun.hotspot.WhiteBox
+ * sun.hotspot.WhiteBox$WhiteBoxPermission
+ *
+ * @run main/othervm/timeout=240 -Xms256M -Xmx256M -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * gc.g1.humongousObjects.ClassLoaderGenerator 1
+ *
+ * @run main/othervm -Xms256M -Xmx256M -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -Xlog:classload,classunload=debug:file=TestHumongousClassLoader_Full_GC.log
+ * -XX:G1HeapRegionSize=1M
+ * gc.g1.humongousObjects.TestHumongousClassLoader FULL_GC
+ *
+ * @run main/othervm -Xms256M -Xmx256M -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -Xlog:classload,classunload=debug:file=TestHumongousClassLoader_Full_GC_Mem_Pressure.log
+ * -XX:G1HeapRegionSize=1M
+ * gc.g1.humongousObjects.TestHumongousClassLoader FULL_GC_MEMORY_PRESSURE
+ *
+ *@run main/othervm -Xms256M -Xmx256M -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:.
+ * -Xlog:classload,classunload=debug:file=TestHumongousClassLoader_CMC.log
+ * -XX:G1HeapRegionSize=1M -XX:MaxTenuringThreshold=1
+ * gc.g1.humongousObjects.TestHumongousClassLoader CMC
+ *
+ */
+
+public class TestHumongousClassLoader {
+
+ private static final WhiteBox WB = WhiteBox.getWhiteBox();
+ private static final String SAMPLE_CLASS_NAME_PREFIX = "SampleClassFiller";
+ public static final String SIMPLE_CLASSLOADER_NAME = "SimpleClassLoader";
+ public static final String HUMONGOUS_CLASSLOADER_NAME = "HumongousClassLoader";
+
+
+ public static final String LOAD_CLASS_METHOD_PROTOTYPE =
+ " @Override\n"
+ + " public Class loadClass(String fileName) throws ClassNotFoundException {\n"
+ + " if (${ClassLoadFilter}) {\n"
+ + " System.out.println(\"Loading class \" + fileName);\n"
+ + " byte[] b = null;\n"
+ + " try {\n"
+ + " b = Files.readAllBytes(new File(fileName + \".class\").toPath());\n"
+ + " } catch (IOException e) {\n"
+ + " e.printStackTrace();\n"
+ + " }\n"
+ + " Class c = defineClass(fileName, b, 0, b.length);\n"
+ + " resolveClass(c);\n"
+ + " return c;\n"
+ + " } else {\n"
+ + " return super.loadClass(fileName);\n"
+ + " }\n"
+ + "\n"
+ + "\n"
+ + " }\n";
+
+ public static final String CLASS_HEADER = "import java.io.File;\n"
+ + "import java.io.IOException;\n"
+ + "import java.nio.file.Files;\n"
+ + "import java.nio.file.Paths;\n";
+
+ public static final String GENERIC_PROTOTYPE = "${ClassHeader}\n"
+ + "public class ${ClassName} extends ${BaseClass}{\n"
+ + " ${ConstructorClause}\n"
+ + " ${Methods}\n"
+ + " ${Fields}\n"
+ + "}\n";
+
+ public static final String CONSTUCTOR_PROTOTYPE = "public ${ClassName}(ClassLoader parent) { super(parent);}\n";
+
+ private enum GC {
+ FULL_GC {
+ @Override
+ public void provoke() {
+ System.gc();
+ }
+ },
+ CMC {
+ @Override
+ public void provoke() {
+ // We need 2 young gc to promote class loader to old gen
+ // Otherwise it will not be unloaded after CMC
+ WHITE_BOX.youngGC();
+ Helpers.waitTillCMCFinished(WHITE_BOX, 0);
+ WHITE_BOX.youngGC();
+ Helpers.waitTillCMCFinished(WHITE_BOX, 0);
+ WHITE_BOX.g1StartConcMarkCycle();
+ Helpers.waitTillCMCFinished(WHITE_BOX, 0);
+ }
+ },
+ FULL_GC_MEMORY_PRESSURE {
+ @Override
+ public void provoke() {
+ WHITE_BOX.fullGC();
+ }
+ };
+ private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
+
+ public abstract void provoke();
+ }
+
+ public static void main(String[] args) throws ClassNotFoundException, InstantiationException,
+ IllegalAccessException, IOException, NoSuchMethodException, InvocationTargetException {
+
+ if (args.length != 1) {
+ throw new Error("Test Bug: Expected GC type wasn't provided as command line argument");
+ }
+ GC gc = GC.valueOf(args[0]);
+
+ Path wrkDir = Paths.get("");
+ URL[] url = {wrkDir.toUri().toURL()};
+ URLClassLoader urlLoader = new URLClassLoader(url);
+
+ Class<?> simpleClassLoaderClass = urlLoader.loadClass(SIMPLE_CLASSLOADER_NAME);
+
+ ClassLoader simpleClassLoader = (ClassLoader) simpleClassLoaderClass
+ .getConstructor(java.lang.ClassLoader.class)
+ .newInstance(TestHumongousClassLoader.class.getClassLoader());
+
+ // Sanity check
+ Asserts.assertEquals(WB.g1IsHumongous(simpleClassLoader), false,
+ "Test Bug: simpleClassLoader is expected to be non-humongous but it's humongous");
+
+
+ Class<?> humongousClassLoaderClass = simpleClassLoader.loadClass(HUMONGOUS_CLASSLOADER_NAME);
+
+ ClassLoader humongousClassLoader = (ClassLoader) humongousClassLoaderClass
+ .getConstructor(java.lang.ClassLoader.class)
+ .newInstance(simpleClassLoader);
+
+ // Sanity check
+ Asserts.assertEquals(WB.g1IsHumongous(humongousClassLoader), true,
+ "Test Bug: humongousClassLoader is expected to be humongous but it's non-humongous");
+
+ //Asserts.assertEquals(1,0);
+
+ Object[] loadedClasses = new Object[]{
+ G1SampleClass.LARGEST_NON_HUMONGOUS.getCls(humongousClassLoader, wrkDir, SAMPLE_CLASS_NAME_PREFIX)
+ .newInstance(),
+ G1SampleClass.SMALLEST_HUMONGOUS.getCls(humongousClassLoader, wrkDir, SAMPLE_CLASS_NAME_PREFIX)
+ .newInstance(),
+ G1SampleClass.ONE_REGION_HUMONGOUS.getCls(humongousClassLoader, wrkDir, SAMPLE_CLASS_NAME_PREFIX)
+ .newInstance(),
+ G1SampleClass.TWO_REGION_HUMONGOUS.getCls(humongousClassLoader, wrkDir, SAMPLE_CLASS_NAME_PREFIX)
+ .newInstance(),
+ };
+
+ // forgetting references to loaded classes
+ for (int i = 0; i < loadedClasses.length; ++i) {
+ loadedClasses[i] = null;
+ }
+
+ // forgetting referencies to classloaders
+ humongousClassLoader = null;
+ humongousClassLoaderClass = null;
+
+ simpleClassLoader = null;
+ simpleClassLoaderClass = null;
+
+ gc.provoke();
+
+ // Test checks
+ Asserts.assertEquals(WB.isClassAlive(HUMONGOUS_CLASSLOADER_NAME), false,
+ String.format("Classloader class %s is loaded after we forget all references to it",
+ HUMONGOUS_CLASSLOADER_NAME));
+
+ for (G1SampleClass sampleClass : G1SampleClass.values()) {
+ String className = Helpers.enumNameToClassName(sampleClass.name()) + "Class";
+ Asserts.assertEquals(WB.isClassAlive(className), false,
+ String.format("Class %s is loaded after we forget all references to it", className));
+ }
+ }
+
+}