BUG-4764: resolve serializer body before javassist callout

This moves the body generation phase out of the javassist lock, so that
it can perform cache lookups without the risk of hitting an AB-BA
deadlock.

Change-Id: I40d0237fef100f90bed9e91e3825a4121e4c503d
Signed-off-by: Robert Varga <rovarga@cisco.com>

diff --git a/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/yangtools/binding/data/codec/gen/impl/AbstractStreamWriterGenerator.java b/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/yangtools/binding/data/codec/gen/impl/AbstractStreamWriterGenerator.java
index 8efdc87ba5d3a5d304a78982b3b3a3d3bca14bc8..e41c4f8594320b92febe52fb1b212ee387642062 100644 (file)
--- a/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/yangtools/binding/data/codec/gen/impl/AbstractStreamWriterGenerator.java
+++ b/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/yangtools/binding/data/codec/gen/impl/AbstractStreamWriterGenerator.java
@@ -188,22 +188,27 @@ abstract class AbstractStreamWriterGenerator extends AbstractGenerator implement
 
     private CtClass generateEmitter0(final Class<?> type, final DataObjectSerializerSource source, final String serializerName) {
         final CtClass product;
+
+        /*
+         * getSerializerBody() has side effects, such as loading classes and codecs, it should be run in model class
+         * loader in order to correctly reference load child classes.
+         *
+         * Furthermore the fact that getSerializedBody() can trigger other code generation to happen, we need to take
+         * care of this before calling instantiatePrototype(), as that will call our customizer with the lock held,
+         * hence any code generation will end up being blocked on the javassist lock.
+         */
+        final String body = ClassLoaderUtils.withClassLoader(type.getClassLoader(), new Supplier<String>() {
+                @Override
+                public String get() {
+                    return source.getSerializerBody().toString();
+                }
+            }
+        );
+
         try {
             product = javassist.instantiatePrototype(DataObjectSerializerPrototype.class.getName(), serializerName, new ClassCustomizer() {
                 @Override
                 public void customizeClass(final CtClass cls) throws CannotCompileException, NotFoundException {
-                    /* getSerializerBody() has side effects, such as loading classes
-                     * and codecs, it should be run in model class loader in order to
-                     * correctly reference load child classes
-                     */
-                    final String body = ClassLoaderUtils.withClassLoader(type.getClassLoader(), new Supplier<String>() {
-                            @Override
-                            public String get() {
-                                return source.getSerializerBody().toString();
-                            }
-                        }
-                    );
-
                     // Generate any static fields
                     for (final StaticConstantDefinition def : source.getStaticConstants()) {
                         final CtField field = new CtField(javassist.asCtClass(def.getType()), def.getName(), cls);