--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/JVMUpcalls.java Tue May 15 20:24:34 2018 +0200
@@ -0,0 +1,143 @@
+/*
+ * Copyright (c) 2016, 2018, 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 jdk.jfr.internal;
+
+import java.lang.reflect.Modifier;
+
+import jdk.jfr.Event;
+import jdk.jfr.internal.handlers.EventHandler;
+import jdk.jfr.internal.instrument.JDKEvents;
+
+/**
+ * All upcalls from the JVM should go through this class.
+ *
+ */
+// Called by native
+final class JVMUpcalls {
+ /**
+ * Called by the JVM when a retransform happens on a tagged class
+ *
+ * @param traceId
+ * Id of the class
+ * @param dummy
+ * (not used but needed since invoke infrastructure in native
+ * uses same signature bytesForEagerInstrumentation)
+ * @param clazz
+ * class being retransformed
+ * @param oldBytes
+ * byte code
+ * @return byte code to use
+ * @throws Throwable
+ */
+ static byte[] onRetransform(long traceId, boolean dummy, Class<?> clazz, byte[] oldBytes) throws Throwable {
+ try {
+ if (Event.class.isAssignableFrom(clazz) && !Modifier.isAbstract(clazz.getModifiers())) {
+ EventHandler handler = Utils.getHandler(clazz.asSubclass(Event.class));
+ if (handler == null) {
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "No event handler found for " + clazz.getName() + ". Ignoring instrumentation request.");
+ // Probably triggered by some other agent
+ return oldBytes;
+ }
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Adding instrumentation to event class " + clazz.getName() + " using retransform");
+ EventInstrumentation ei = new EventInstrumentation(clazz.getSuperclass(), oldBytes, traceId);
+ byte[] bytes = ei.buildInstrumented();
+ ASMToolkit.logASM(clazz.getName(), bytes);
+ return bytes;
+ }
+ return JDKEvents.retransformCallback(clazz, oldBytes);
+ } catch (Throwable t) {
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Unexpected error when adding instrumentation to event class " + clazz.getName());
+ }
+ return oldBytes;
+
+ }
+
+ /**
+ * Called by the JVM when requested to do an "eager" instrumentation. Would
+ * normally happen when JVMTI retransform capabilities are not available.
+ *
+ * @param traceId
+ * Id of the class
+ * @param forceInstrumentation
+ * add instrumentation regardless if event is enabled or not.
+ * @param superClazz
+ * the super class of the class being processed
+ * @param oldBytes
+ * byte code
+ * @return byte code to use
+ * @throws Throwable
+ */
+ static byte[] bytesForEagerInstrumentation(long traceId, boolean forceInstrumentation, Class<?> superClass, byte[] oldBytes) throws Throwable {
+ if (JVMSupport.isNotAvailable()) {
+ return oldBytes;
+ }
+ String eventName = "<Unknown>";
+ try {
+ EventInstrumentation ei = new EventInstrumentation(superClass, oldBytes, traceId);
+ eventName = ei.getEventName();
+ if (!forceInstrumentation) {
+ // Assume we are recording
+ MetadataRepository mr = MetadataRepository.getInstance();
+ // No need to generate bytecode if:
+ // 1) Event class is disabled, and there is not an external configuration that overrides.
+ // 2) Event class has @Registered(false)
+ if (!mr.isEnabled(ei.getEventName()) && !ei.isEnabled() || !ei.isRegistered()) {
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Skipping instrumentation for event type " + eventName + " since event was disabled on class load");
+ return oldBytes;
+ }
+ }
+ // Corner case when we are forced to generate bytecode. We can't reference the event
+ // handler in #isEnabled() before event class has been registered, so we add a
+ // guard against a null reference.
+ ei.setGuardHandler(true);
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.INFO, "Adding " + (forceInstrumentation ? "forced " : "") + "instrumentation for event type " + eventName + " during initial class load");
+ EventHandlerCreator eh = new EventHandlerCreator(traceId, ei.getSettingInfos(), ei.getFieldInfos());
+ // Handler class must be loaded before instrumented event class can
+ // be used
+ eh.makeEventHandlerClass();
+ byte[] bytes = ei.buildInstrumented();
+ ASMToolkit.logASM(ei.getClassName() + "(" + traceId + ")", bytes);
+ return bytes;
+ } catch (Throwable t) {
+ Logger.log(LogTag.JFR_SYSTEM, LogLevel.WARN, "Unexpected error when adding instrumentation for event type " + eventName);
+ return oldBytes;
+ }
+ }
+
+ /**
+ * Called by the JVM to create the recorder thread.
+ *
+ * @param systemThreadGroup
+ * the system thread group
+ *
+ * @param contextClassLoader
+ * the context class loader.
+ *
+ * @return a new thread
+ */
+ static Thread createRecorderThread(ThreadGroup systemThreadGroup, ClassLoader contextClassLoader) {
+ return SecuritySupport.createRecorderThread(systemThreadGroup, contextClassLoader);
+ }
+}