Merge

hotspot/src/os/windows/vm/os_windows.cpp

@@ -3619,13 +3619,14 @@ bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
          "possibility of dangling Thread pointer");
 
   OSThread* osthread = thread->osthread();
-  bool interrupted = osthread->interrupted();
   // There is no synchronization between the setting of the interrupt
   // and it being cleared here. It is critical - see 6535709 - that
   // we only clear the interrupt state, and reset the interrupt event,
   // if we are going to report that we were indeed interrupted - else
   // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
-  // depending on the timing
+  // depending on the timing. By checking thread interrupt event to see
+  // if the thread gets real interrupt thus prevent spurious wakeup.
+  bool interrupted = osthread->interrupted() && (WaitForSingleObject(osthread->interrupt_event(), 0) == WAIT_OBJECT_0);
   if (interrupted && clear_interrupted) {
     osthread->set_interrupted(false);
     ResetEvent(osthread->interrupt_event());

hotspot/src/share/vm/code/debugInfo.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, 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
@@ -273,8 +273,8 @@ class DebugInfoReadStream : public CompressedReadStream {
   }
   Method* read_method() {
     Method* o = (Method*)(code()->metadata_at(read_int()));
-    assert(o == NULL ||
-           o->is_metaspace_object(), "meta data only");
+    // is_metadata() is a faster check than is_metaspace_object()
+    assert(o == NULL || o->is_metadata(), "meta data only");
     return o;
   }
   ScopeValue* read_object_value();

hotspot/src/share/vm/oops/constantPool.cpp

@@ -1295,6 +1295,7 @@ void ConstantPool::copy_entry_to(constantPoolHandle from_cp, int from_i,
   } break;
 
   case JVM_CONSTANT_UnresolvedClass:
+  case JVM_CONSTANT_UnresolvedClassInError:
   {
     // Can be resolved after checking tag, so check the slot first.
     CPSlot entry = from_cp->slot_at(from_i);

hotspot/src/share/vm/oops/metadata.hpp

@@ -42,6 +42,7 @@ class Metadata : public MetaspaceObj {
   // Rehashing support for tables containing pointers to this
   unsigned int new_hash(juint seed)   { ShouldNotReachHere();  return 0; }
 
+  virtual bool is_metadata()           const volatile { return true; }
   virtual bool is_klass()              const volatile { return false; }
   virtual bool is_method()             const volatile { return false; }
   virtual bool is_methodData()         const volatile { return false; }

hotspot/src/share/vm/opto/library_call.cpp

@@ -3180,7 +3180,8 @@ bool LibraryCallKit::inline_native_currentThread() {
 // private native boolean java.lang.Thread.isInterrupted(boolean ClearInterrupted);
 bool LibraryCallKit::inline_native_isInterrupted() {
   // Add a fast path to t.isInterrupted(clear_int):
-  //   (t == Thread.current() && (!TLS._osthread._interrupted || !clear_int))
+  //   (t == Thread.current() &&
+  //    (!TLS._osthread._interrupted || WINDOWS_ONLY(false) NOT_WINDOWS(!clear_int)))
   //   ? TLS._osthread._interrupted : /*slow path:*/ t.isInterrupted(clear_int)
   // So, in the common case that the interrupt bit is false,
   // we avoid making a call into the VM.  Even if the interrupt bit
@@ -3237,6 +3238,7 @@ bool LibraryCallKit::inline_native_isInterrupted() {
   // drop through to next case
   set_control( _gvn.transform(new (C) IfTrueNode(iff_bit)));
 
+#ifndef TARGET_OS_FAMILY_windows
   // (c) Or, if interrupt bit is set and clear_int is false, use 2nd fast path.
   Node* clr_arg = argument(1);
   Node* cmp_arg = _gvn.transform(new (C) CmpINode(clr_arg, intcon(0)));
@@ -3250,6 +3252,10 @@ bool LibraryCallKit::inline_native_isInterrupted() {
 
   // drop through to next case
   set_control( _gvn.transform(new (C) IfTrueNode(iff_arg)));
+#else
+  // To return true on Windows you must read the _interrupted field
+  // and check the the event state i.e. take the slow path.
+#endif // TARGET_OS_FAMILY_windows
 
   // (d) Otherwise, go to the slow path.
   slow_region->add_req(control());

hotspot/src/share/vm/prims/jvm.cpp

@@ -4360,7 +4360,7 @@ JVM_END
 
 JVM_ENTRY(void, JVM_GetVersionInfo(JNIEnv* env, jvm_version_info* info, size_t info_size))
 {
-  memset(info, 0, sizeof(info_size));
+  memset(info, 0, info_size);
 
   info->jvm_version = Abstract_VM_Version::jvm_version();
   info->update_version = 0;          /* 0 in HotSpot Express VM */

hotspot/src/share/vm/prims/jvmtiEnv.cpp

@@ -1464,7 +1464,19 @@ JvmtiEnv::PopFrame(JavaThread* java_thread) {
     // It's fine to update the thread state here because no JVMTI events
     // shall be posted for this PopFrame.
 
+    // It is only safe to perform the direct operation on the current
+    // thread. All other usage needs to use a vm-safepoint-op for safety.
+    if (java_thread == JavaThread::current()) {
       state->update_for_pop_top_frame();
+    } else {
+      VM_UpdateForPopTopFrame op(state);
+      VMThread::execute(&op);
+      jvmtiError err = op.result();
+      if (err != JVMTI_ERROR_NONE) {
+        return err;
+      }
+    }
+
     java_thread->set_popframe_condition(JavaThread::popframe_pending_bit);
     // Set pending step flag for this popframe and it is cleared when next
     // step event is posted.
@@ -1505,6 +1517,7 @@ JvmtiEnv::GetFrameLocation(JavaThread* java_thread, jint depth, jmethodID* metho
 // depth - pre-checked as non-negative
 jvmtiError
 JvmtiEnv::NotifyFramePop(JavaThread* java_thread, jint depth) {
+  jvmtiError err = JVMTI_ERROR_NONE;
   ResourceMark rm;
   uint32_t debug_bits = 0;
 
@@ -1532,10 +1545,17 @@ JvmtiEnv::NotifyFramePop(JavaThread* java_thread, jint depth) {
 
   assert(vf->frame_pointer() != NULL, "frame pointer mustn't be NULL");
 
+  // It is only safe to perform the direct operation on the current
+  // thread. All other usage needs to use a vm-safepoint-op for safety.
+  if (java_thread == JavaThread::current()) {
     int frame_number = state->count_frames() - depth;
     state->env_thread_state(this)->set_frame_pop(frame_number);
-
-  return JVMTI_ERROR_NONE;
+  } else {
+    VM_SetFramePop op(this, state, depth);
+    VMThread::execute(&op);
+    err = op.result();
+  }
+  return err;
 } /* end NotifyFramePop */
 
 

hotspot/src/share/vm/prims/jvmtiEnvBase.hpp

@@ -29,6 +29,7 @@
 #include "prims/jvmtiEnvThreadState.hpp"
 #include "prims/jvmtiEventController.hpp"
 #include "prims/jvmtiThreadState.hpp"
+#include "prims/jvmtiThreadState.inline.hpp"
 #include "runtime/fieldDescriptor.hpp"
 #include "runtime/frame.hpp"
 #include "runtime/handles.inline.hpp"
@@ -334,6 +335,60 @@ class JvmtiEnvIterator : public StackObj {
   JvmtiEnv* next(JvmtiEnvBase* env) { return env->next_environment(); }
 };
 
+// VM operation to update for pop top frame.
+class VM_UpdateForPopTopFrame : public VM_Operation {
+private:
+  JvmtiThreadState* _state;
+  jvmtiError _result;
+
+public:
+  VM_UpdateForPopTopFrame(JvmtiThreadState* state) {
+    _state = state;
+    _result = JVMTI_ERROR_NONE;
+  }
+  VMOp_Type type() const { return VMOp_UpdateForPopTopFrame; }
+  jvmtiError result() { return _result; }
+  void doit() {
+    JavaThread* jt = _state->get_thread();
+    if (Threads::includes(jt) && !jt->is_exiting() && jt->threadObj() != NULL) {
+      _state->update_for_pop_top_frame();
+    } else {
+      _result = JVMTI_ERROR_THREAD_NOT_ALIVE;
+    }
+  }
+};
+
+// VM operation to set frame pop.
+class VM_SetFramePop : public VM_Operation {
+private:
+  JvmtiEnv *_env;
+  JvmtiThreadState* _state;
+  jint _depth;
+  jvmtiError _result;
+
+public:
+  VM_SetFramePop(JvmtiEnv *env, JvmtiThreadState* state, jint depth) {
+    _env = env;
+    _state = state;
+    _depth = depth;
+    _result = JVMTI_ERROR_NONE;
+  }
+  // Nested operation must be allowed for the VM_EnterInterpOnlyMode that is
+  // called from the JvmtiEventControllerPrivate::recompute_thread_enabled.
+  bool allow_nested_vm_operations() const { return true; }
+  VMOp_Type type() const { return VMOp_SetFramePop; }
+  jvmtiError result() { return _result; }
+  void doit() {
+    JavaThread* jt = _state->get_thread();
+    if (Threads::includes(jt) && !jt->is_exiting() && jt->threadObj() != NULL) {
+      int frame_number = _state->count_frames() - _depth;
+      _state->env_thread_state((JvmtiEnvBase*)_env)->set_frame_pop(frame_number);
+    } else {
+      _result = JVMTI_ERROR_THREAD_NOT_ALIVE;
+    }
+  }
+};
+
 
 // VM operation to get monitor information with stack depth.
 class VM_GetOwnedMonitorInfo : public VM_Operation {

hotspot/src/share/vm/prims/jvmtiEnvThreadState.cpp

@@ -190,12 +190,8 @@ void JvmtiEnvThreadState::compare_and_set_current_location(Method* new_method,
 
 
 JvmtiFramePops* JvmtiEnvThreadState::get_frame_pops() {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "frame pop data only accessible from same thread or while suspended");
-
+  assert(get_thread() == Thread::current() || SafepointSynchronize::is_at_safepoint(),
+         "frame pop data only accessible from same thread or at safepoint");
   if (_frame_pops == NULL) {
     _frame_pops = new JvmtiFramePops();
     assert(_frame_pops != NULL, "_frame_pops != NULL");
@@ -209,44 +205,32 @@ bool JvmtiEnvThreadState::has_frame_pops() {
 }
 
 void JvmtiEnvThreadState::set_frame_pop(int frame_number) {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "frame pop data only accessible from same thread or while suspended");
+  assert(get_thread() == Thread::current() || SafepointSynchronize::is_at_safepoint(),
+         "frame pop data only accessible from same thread or at safepoint");
   JvmtiFramePop fpop(frame_number);
   JvmtiEventController::set_frame_pop(this, fpop);
 }
 
 
 void JvmtiEnvThreadState::clear_frame_pop(int frame_number) {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "frame pop data only accessible from same thread or while suspended");
+  assert(get_thread() == Thread::current() || SafepointSynchronize::is_at_safepoint(),
+         "frame pop data only accessible from same thread or at safepoint");
   JvmtiFramePop fpop(frame_number);
   JvmtiEventController::clear_frame_pop(this, fpop);
 }
 
 
 void JvmtiEnvThreadState::clear_to_frame_pop(int frame_number)  {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "frame pop data only accessible from same thread or while suspended");
+  assert(get_thread() == Thread::current() || SafepointSynchronize::is_at_safepoint(),
+         "frame pop data only accessible from same thread or at safepoint");
   JvmtiFramePop fpop(frame_number);
   JvmtiEventController::clear_to_frame_pop(this, fpop);
 }
 
 
 bool JvmtiEnvThreadState::is_frame_pop(int cur_frame_number) {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "frame pop data only accessible from same thread or while suspended");
+  assert(get_thread() == Thread::current() || SafepointSynchronize::is_at_safepoint(),
+         "frame pop data only accessible from same thread or at safepoint");
   if (!get_thread()->is_interp_only_mode() || _frame_pops == NULL) {
     return false;
   }

hotspot/src/share/vm/prims/jvmtiEventController.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2014, 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
@@ -989,21 +989,21 @@ JvmtiEventController::set_extension_event_callback(JvmtiEnvBase *env,
 
 void
 JvmtiEventController::set_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
-  MutexLocker mu(JvmtiThreadState_lock);
+  MutexLockerEx mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
   JvmtiEventControllerPrivate::set_frame_pop(ets, fpop);
 }
 
 
 void
 JvmtiEventController::clear_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
-  MutexLocker mu(JvmtiThreadState_lock);
+  MutexLockerEx mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
   JvmtiEventControllerPrivate::clear_frame_pop(ets, fpop);
 }
 
 
 void
 JvmtiEventController::clear_to_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
-  MutexLocker mu(JvmtiThreadState_lock);
+  MutexLockerEx mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
   JvmtiEventControllerPrivate::clear_to_frame_pop(ets, fpop);
 }
 

hotspot/src/share/vm/prims/jvmtiThreadState.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2014, 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
@@ -63,6 +63,7 @@ JvmtiThreadState::JvmtiThreadState(JavaThread* thread)
   _vm_object_alloc_event_collector = NULL;
   _the_class_for_redefinition_verification = NULL;
   _scratch_class_for_redefinition_verification = NULL;
+  _cur_stack_depth = UNKNOWN_STACK_DEPTH;
 
   // JVMTI ForceEarlyReturn support
   _pending_step_for_earlyret = false;
@@ -213,12 +214,9 @@ void JvmtiThreadState::leave_interp_only_mode() {
 
 // Helper routine used in several places
 int JvmtiThreadState::count_frames() {
-#ifdef ASSERT
-  uint32_t debug_bits = 0;
-#endif
-  assert(SafepointSynchronize::is_at_safepoint() ||
-         JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-         "at safepoint or must be suspended");
+  guarantee(SafepointSynchronize::is_at_safepoint() ||
+    (JavaThread *)Thread::current() == get_thread(),
+    "must be current thread or at safepoint");
 
   if (!get_thread()->has_last_Java_frame()) return 0;  // no Java frames
 
@@ -243,15 +241,9 @@ int JvmtiThreadState::count_frames() {
 
 
 void JvmtiThreadState::invalidate_cur_stack_depth() {
-  Thread *cur = Thread::current();
-  uint32_t debug_bits = 0;
-
-  // The caller can be the VMThread at a safepoint, the current thread
-  // or the target thread must be suspended.
-  guarantee((cur->is_VM_thread() && SafepointSynchronize::is_at_safepoint()) ||
-    (JavaThread *)cur == get_thread() ||
-    JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-    "sanity check");
+  guarantee(SafepointSynchronize::is_at_safepoint() ||
+    (JavaThread *)Thread::current() == get_thread(),
+    "must be current thread or at safepoint");
 
   _cur_stack_depth = UNKNOWN_STACK_DEPTH;
 }
@@ -280,10 +272,9 @@ void JvmtiThreadState::decr_cur_stack_depth() {
 }
 
 int JvmtiThreadState::cur_stack_depth() {
-  uint32_t debug_bits = 0;
-  guarantee(JavaThread::current() == get_thread() ||
-    JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
-    "must be current thread or suspended");
+  guarantee(SafepointSynchronize::is_at_safepoint() ||
+    (JavaThread *)Thread::current() == get_thread(),
+    "must be current thread or at safepoint");
 
   if (!is_interp_only_mode() || _cur_stack_depth == UNKNOWN_STACK_DEPTH) {
     _cur_stack_depth = count_frames();

hotspot/src/share/vm/runtime/vm_operations.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, 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
@@ -74,6 +74,8 @@
   template(PopulateDumpSharedSpace)               \
   template(JNIFunctionTableCopier)                \
   template(RedefineClasses)                       \
+  template(UpdateForPopTopFrame)                  \
+  template(SetFramePop)                           \
   template(GetOwnedMonitorInfo)                   \
   template(GetObjectMonitorUsage)                 \
   template(GetCurrentContendedMonitor)            \

hotspot/test/runtime/6294277/SourceDebugExtension.java

@@ -25,7 +25,7 @@
  * @test
  * @bug 6294277
  * @summary java -Xdebug crashes on SourceDebugExtension attribute larger than 64K
- * @run main/othervm -Xdebug -Xrunjdwp:transport=dt_socket,address=8888,server=y,suspend=n SourceDebugExtension
+ * @run main/othervm -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n SourceDebugExtension
  */
 import java.io.*;
 

hotspot/test/serviceability/jvmti/TestRedefineWithUnresolvedClass.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2014, 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.
+ */
+
+/*
+ * @test
+ * @summary Redefine a class with an UnresolvedClass reference in the constant pool.
+ * @bug 8035150
+ * @library /testlibrary
+ * @build UnresolvedClassAgent com.oracle.java.testlibrary.ProcessTools com.oracle.java.testlibrary.OutputAnalyzer
+ * @run main TestRedefineWithUnresolvedClass
+ */
+
+import java.io.File;
+import java.util.Arrays;
+
+import com.oracle.java.testlibrary.OutputAnalyzer;
+import com.oracle.java.testlibrary.ProcessTools;
+
+public class TestRedefineWithUnresolvedClass {
+
+    final static String slash = File.separator;
+    final static String testClasses = System.getProperty("test.classes") + slash;
+
+    public static void main(String... args) throws Throwable {
+        // delete this class to cause a NoClassDefFoundError
+        File unresolved = new File(testClasses, "MyUnresolvedClass.class");
+        if (unresolved.exists() && !unresolved.delete()) {
+            throw new Exception("Could not delete: " + unresolved);
+        }
+
+        // build the javaagent
+        buildJar("UnresolvedClassAgent");
+
+        // launch a VM with the javaagent
+        launchTest();
+    }
+
+    private static void buildJar(String jarName) throws Throwable {
+        String testSrc = System.getProperty("test.src", "?") + slash;
+
+        String jarPath = String.format("%s%s.jar", testClasses, jarName);
+        String manifestPath = String.format("%s%s.mf", testSrc, jarName);
+        String className = String.format("%s.class", jarName);
+
+        String[] args = new String[] {"-cfm", jarPath, manifestPath, "-C", testClasses, className};
+
+        System.out.println("Running jar " + Arrays.toString(args));
+        sun.tools.jar.Main jarTool = new sun.tools.jar.Main(System.out, System.err, "jar");
+        if (!jarTool.run(args)) {
+            throw new Exception("jar failed: args=" + Arrays.toString(args));
+        }
+    }
+
+    private static void launchTest() throws Throwable {
+        String[] args = {
+            "-javaagent:" + testClasses + "UnresolvedClassAgent.jar",
+            "-Dtest.classes=" + testClasses,
+            "UnresolvedClassAgent" };
+        OutputAnalyzer output = ProcessTools.executeTestJvm(args);
+        output.shouldHaveExitValue(0);
+    }
+}

hotspot/test/serviceability/jvmti/UnresolvedClassAgent.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2014, 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.
+ */
+
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.lang.instrument.ClassDefinition;
+import java.lang.instrument.Instrumentation;
+
+/*
+ * This class is present during compilation, but will be deleted before execution.
+ */
+class MyUnresolvedClass {
+    static void bar() {
+    }
+}
+
+class MyRedefinedClass {
+    static void foo() {
+        MyUnresolvedClass.bar();
+    }
+}
+
+public class UnresolvedClassAgent {
+    public static void main(String... args) {
+    }
+
+    public static void premain(String args, Instrumentation inst) throws Exception {
+        try {
+            MyRedefinedClass.foo();
+        } catch(NoClassDefFoundError err) {
+            System.out.println("NoClassDefFoundError (expected)");
+        }
+
+        File f = new File(System.getProperty("test.classes"), "MyRedefinedClass.class");
+        byte[] buf = new byte[(int)f.length()];
+        try (DataInputStream dis = new DataInputStream(new FileInputStream(f))) {
+            dis.readFully(buf);
+        }
+        ClassDefinition cd = new ClassDefinition(MyRedefinedClass.class, buf);
+        inst.redefineClasses(new ClassDefinition[] {cd});
+
+        try {
+            MyRedefinedClass.foo();
+        } catch(NoClassDefFoundError err) {
+            System.out.println("NoClassDefFoundError (expected again)");
+        }
+    }
+}

hotspot/test/serviceability/jvmti/UnresolvedClassAgent.mf

@@ -0,0 +1,3 @@
+Manifest-Version: 1.0
+Premain-Class: UnresolvedClassAgent
+Can-Redefine-Classes: true

hotspot/test/testlibrary/com/oracle/java/testlibrary/ProcessTools.java

@@ -163,10 +163,87 @@ public final class ProcessTools {
 
     // Reporting
     StringBuilder cmdLine = new StringBuilder();
-    for (String cmd : args)
+    for (String cmd : args) {
       cmdLine.append(cmd).append(' ');
+    }
     System.out.println("Command line: [" + cmdLine.toString() + "]");
 
     return new ProcessBuilder(args.toArray(new String[args.size()]));
   }
+
+  /**
+   * Executes a test jvm process, waits for it to finish and returns the process output.
+   * The default jvm options from jtreg, test.vm.opts and test.java.opts, are added.
+   * The java from the test.jdk is used to execute the command.
+   *
+   * The command line will be like:
+   * {test.jdk}/bin/java {test.vm.opts} {test.java.opts} cmds
+   *
+   * @param cmds User specifed arguments.
+   * @return The output from the process.
+   */
+  public static OutputAnalyzer executeTestJvm(String... cmds) throws Throwable {
+    ProcessBuilder pb = createJavaProcessBuilder(Utils.addTestJavaOpts(cmds));
+    return executeProcess(pb);
+  }
+
+  /**
+   * Executes a process, waits for it to finish and returns the process output.
+   * @param pb The ProcessBuilder to execute.
+   * @return The output from the process.
+   */
+  public static OutputAnalyzer executeProcess(ProcessBuilder pb) throws Throwable {
+    OutputAnalyzer output = null;
+    try {
+      output = new OutputAnalyzer(pb.start());
+      return output;
+    } catch (Throwable t) {
+      System.out.println("executeProcess() failed: " + t);
+      throw t;
+    } finally {
+      System.out.println(getProcessLog(pb, output));
+    }
+  }
+
+  /**
+   * Executes a process, waits for it to finish and returns the process output.
+   * @param cmds The command line to execute.
+   * @return The output from the process.
+   */
+  public static OutputAnalyzer executeProcess(String... cmds) throws Throwable {
+    return executeProcess(new ProcessBuilder(cmds));
+  }
+
+  /**
+   * Used to log command line, stdout, stderr and exit code from an executed process.
+   * @param pb The executed process.
+   * @param output The output from the process.
+   */
+  public static String getProcessLog(ProcessBuilder pb, OutputAnalyzer output) {
+    String stderr = output == null ? "null" : output.getStderr();
+    String stdout = output == null ? "null" : output.getStdout();
+    String exitValue = output == null ? "null": Integer.toString(output.getExitValue());
+    StringBuilder logMsg = new StringBuilder();
+    final String nl = System.getProperty("line.separator");
+    logMsg.append("--- ProcessLog ---" + nl);
+    logMsg.append("cmd: " + getCommandLine(pb) + nl);
+    logMsg.append("exitvalue: " + exitValue + nl);
+    logMsg.append("stderr: " + stderr + nl);
+    logMsg.append("stdout: " + stdout + nl);
+    return logMsg.toString();
+  }
+
+  /**
+   * @return The full command line for the ProcessBuilder.
+   */
+  public static String getCommandLine(ProcessBuilder pb) {
+    if (pb == null) {
+      return "null";
+    }
+    StringBuilder cmd = new StringBuilder();
+    for (String s : pb.command()) {
+      cmd.append(s).append(" ");
+    }
+    return cmd.toString().trim();
+  }
 }

hotspot/test/testlibrary/com/oracle/java/testlibrary/Utils.java

@@ -0,0 +1,263 @@
+/*
+ * Copyright (c) 2013, 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 com.oracle.java.testlibrary;
+
+import static com.oracle.java.testlibrary.Asserts.assertTrue;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.ServerSocket;
+import java.net.UnknownHostException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.regex.Pattern;
+import java.util.regex.Matcher;
+
+/**
+ * Common library for various test helper functions.
+ */
+public final class Utils {
+
+    /**
+     * Returns the sequence used by operating system to separate lines.
+     */
+    public static final String NEW_LINE = System.getProperty("line.separator");
+
+    /**
+     * Returns the value of 'test.vm.opts'system property.
+     */
+    public static final String VM_OPTIONS = System.getProperty("test.vm.opts", "").trim();
+
+    /**
+     * Returns the value of 'test.java.opts'system property.
+     */
+    public static final String JAVA_OPTIONS = System.getProperty("test.java.opts", "").trim();
+
+    /**
+    * Returns the value of 'test.timeout.factor' system property
+    * converted to {@code double}.
+    */
+    public static final double TIMEOUT_FACTOR;
+    static {
+        String toFactor = System.getProperty("test.timeout.factor", "1.0");
+        TIMEOUT_FACTOR = Double.parseDouble(toFactor);
+    }
+
+    private Utils() {
+        // Private constructor to prevent class instantiation
+    }
+
+    /**
+     * Returns the list of VM options.
+     *
+     * @return List of VM options
+     */
+    public static List<String> getVmOptions() {
+        return Arrays.asList(safeSplitString(VM_OPTIONS));
+    }
+
+    /**
+     * Returns the list of VM options with -J prefix.
+     *
+     * @return The list of VM options with -J prefix
+     */
+    public static List<String> getForwardVmOptions() {
+        String[] opts = safeSplitString(VM_OPTIONS);
+        for (int i = 0; i < opts.length; i++) {
+            opts[i] = "-J" + opts[i];
+        }
+        return Arrays.asList(opts);
+    }
+
+    /**
+     * Returns the default JTReg arguments for a jvm running a test.
+     * This is the combination of JTReg arguments test.vm.opts and test.java.opts.
+     * @return An array of options, or an empty array if no opptions.
+     */
+    public static String[] getTestJavaOpts() {
+        List<String> opts = new ArrayList<String>();
+        Collections.addAll(opts, safeSplitString(VM_OPTIONS));
+        Collections.addAll(opts, safeSplitString(JAVA_OPTIONS));
+        return opts.toArray(new String[0]);
+    }
+
+    /**
+     * Combines given arguments with default JTReg arguments for a jvm running a test.
+     * This is the combination of JTReg arguments test.vm.opts and test.java.opts
+     * @return The combination of JTReg test java options and user args.
+     */
+    public static String[] addTestJavaOpts(String... userArgs) {
+        List<String> opts = new ArrayList<String>();
+        Collections.addAll(opts, getTestJavaOpts());
+        Collections.addAll(opts, userArgs);
+        return opts.toArray(new String[0]);
+    }
+
+    /**
+     * Splits a string by white space.
+     * Works like String.split(), but returns an empty array
+     * if the string is null or empty.
+     */
+    private static String[] safeSplitString(String s) {
+        if (s == null || s.trim().isEmpty()) {
+            return new String[] {};
+        }
+        return s.trim().split("\\s+");
+    }
+
+    /**
+     * @return The full command line for the ProcessBuilder.
+     */
+    public static String getCommandLine(ProcessBuilder pb) {
+        StringBuilder cmd = new StringBuilder();
+        for (String s : pb.command()) {
+            cmd.append(s).append(" ");
+        }
+        return cmd.toString();
+    }
+
+    /**
+     * Returns the free port on the local host.
+     * The function will spin until a valid port number is found.
+     *
+     * @return The port number
+     * @throws InterruptedException if any thread has interrupted the current thread
+     * @throws IOException if an I/O error occurs when opening the socket
+     */
+    public static int getFreePort() throws InterruptedException, IOException {
+        int port = -1;
+
+        while (port <= 0) {
+            Thread.sleep(100);
+
+            ServerSocket serverSocket = null;
+            try {
+                serverSocket = new ServerSocket(0);
+                port = serverSocket.getLocalPort();
+            } finally {
+                serverSocket.close();
+            }
+        }
+
+        return port;
+    }
+
+    /**
+     * Returns the name of the local host.
+     *
+     * @return The host name
+     * @throws UnknownHostException if IP address of a host could not be determined
+     */
+    public static String getHostname() throws UnknownHostException {
+        InetAddress inetAddress = InetAddress.getLocalHost();
+        String hostName = inetAddress.getHostName();
+
+        assertTrue((hostName != null && !hostName.isEmpty()),
+                "Cannot get hostname");
+
+        return hostName;
+    }
+
+    /**
+     * Uses "jcmd -l" to search for a jvm pid. This function will wait
+     * forever (until jtreg timeout) for the pid to be found.
+     * @param key Regular expression to search for
+     * @return The found pid.
+     */
+    public static int waitForJvmPid(String key) throws Throwable {
+        final long iterationSleepMillis = 250;
+        System.out.println("waitForJvmPid: Waiting for key '" + key + "'");
+        System.out.flush();
+        while (true) {
+            int pid = tryFindJvmPid(key);
+            if (pid >= 0) {
+                return pid;
+            }
+            Thread.sleep(iterationSleepMillis);
+        }
+    }
+
+    /**
+     * Searches for a jvm pid in the output from "jcmd -l".
+     *
+     * Example output from jcmd is:
+     * 12498 sun.tools.jcmd.JCmd -l
+     * 12254 /tmp/jdk8/tl/jdk/JTwork/classes/com/sun/tools/attach/Application.jar
+     *
+     * @param key A regular expression to search for.
+     * @return The found pid, or -1 if Enot found.
+     * @throws Exception If multiple matching jvms are found.
+     */
+    public static int tryFindJvmPid(String key) throws Throwable {
+        OutputAnalyzer output = null;
+        try {
+            JDKToolLauncher jcmdLauncher = JDKToolLauncher.create("jcmd");
+            jcmdLauncher.addToolArg("-l");
+            output = ProcessTools.executeProcess(jcmdLauncher.getCommand());
+            output.shouldHaveExitValue(0);
+
+            // Search for a line starting with numbers (pid), follwed by the key.
+            Pattern pattern = Pattern.compile("([0-9]+)\\s.*(" + key + ").*\\r?\\n");
+            Matcher matcher = pattern.matcher(output.getStdout());
+
+            int pid = -1;
+            if (matcher.find()) {
+                pid = Integer.parseInt(matcher.group(1));
+                System.out.println("findJvmPid.pid: " + pid);
+                if (matcher.find()) {
+                    throw new Exception("Found multiple JVM pids for key: " + key);
+                }
+            }
+            return pid;
+        } catch (Throwable t) {
+            System.out.println(String.format("Utils.findJvmPid(%s) failed: %s", key, t));
+            throw t;
+        }
+    }
+
+    /**
+     * Returns file content as a list of strings
+     *
+     * @param file File to operate on
+     * @return List of strings
+     * @throws IOException
+     */
+    public static List<String> fileAsList(File file) throws IOException {
+        assertTrue(file.exists() && file.isFile(),
+                file.getAbsolutePath() + " does not exist or not a file");
+        List<String> output = new ArrayList<>();
+        try (BufferedReader reader = new BufferedReader(new FileReader(file.getAbsolutePath()))) {
+            while (reader.ready()) {
+                output.add(reader.readLine().replace(NEW_LINE, ""));
+            }
+        }
+        return output;
+    }
+
+}