8081219: hs_err improvement: Add event logging for class redefinition to the hs_err file

Summary: Use the Events::log function to save redefined classes for output to the hs_err file
Reviewed-by: dholmes

src/share/vm/prims/jvmtiRedefineClasses.cpp

 /*
- * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2017, 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
@@ -42,6 +42,7 @@
 #include "runtime/deoptimization.hpp"
 #include "runtime/relocator.hpp"
 #include "utilities/bitMap.inline.hpp"
+#include "utilities/events.hpp"
 
 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
 
@@ -172,6 +173,9 @@ void VM_RedefineClasses::doit_epilogue() {
   // Free os::malloc allocated memory.
   os::free(_scratch_classes);
 
+  // Reset the_class_oop to null for error printing.
+  _the_class_oop = NULL;
+
   if (RC_TRACE_ENABLED(0x00000004)) {
     // Used to have separate timers for "doit" and "all", but the timer
     // overhead skewed the measurements.
@@ -4096,6 +4100,13 @@ void VM_RedefineClasses::redefine_single_class(jclass the_jclass,
     java_lang_Class::classRedefinedCount(the_class_mirror),
     os::available_memory() >> 10));
 
+  {
+    ResourceMark rm(THREAD);
+    Events::log_redefinition(THREAD, "redefined class name=%s, count=%d",
+                             the_class->external_name(),
+                             java_lang_Class::classRedefinedCount(the_class_mirror));
+
+  }
   RC_TIMER_STOP(_timer_rsc_phase2);
 } // end redefine_single_class()
 
@@ -4240,3 +4251,11 @@ void VM_RedefineClasses::dump_methods() {
     tty->cr();
   }
 }
+
+void VM_RedefineClasses::print_on_error(outputStream* st) const {
+  VM_Operation::print_on_error(st);
+  if (_the_class_oop != NULL) {
+    ResourceMark rm;
+    st->print_cr(", redefining class %s", _the_class_oop->external_name());
+  }
+}

src/share/vm/prims/jvmtiRedefineClasses.hpp

 /*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2017, 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
@@ -538,5 +538,8 @@ class VM_RedefineClasses: public VM_Operation {
   static unsigned char * get_cached_class_file_bytes(JvmtiCachedClassFileData *cache) {
     return cache == NULL ? NULL : cache->data;
   }
+
+  // Error printing
+  void print_on_error(outputStream* st) const;
 };
 #endif // SHARE_VM_PRIMS_JVMTIREDEFINECLASSES_HPP

src/share/vm/runtime/vm_operations.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2017, 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
@@ -183,7 +183,7 @@ class VM_Operation: public CHeapObj<mtInternal> {
   static const char* mode_to_string(Mode mode);
 
   // Debugging
-  void print_on_error(outputStream* st) const;
+  virtual void print_on_error(outputStream* st) const;
   const char* name() const { return _names[type()]; }
   static const char* name(int type) {
     assert(type >= 0 && type < VMOp_Terminating, "invalid VM operation type");

src/share/vm/utilities/events.cpp

 /*
- * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2017, 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
@@ -36,6 +36,7 @@
 EventLog* Events::_logs = NULL;
 StringEventLog* Events::_messages = NULL;
 StringEventLog* Events::_exceptions = NULL;
+StringEventLog* Events::_redefinitions = NULL;
 StringEventLog* Events::_deopt_messages = NULL;
 
 EventLog::EventLog() {
@@ -65,6 +66,7 @@ void Events::init() {
   if (LogEvents) {
     _messages = new StringEventLog("Events");
     _exceptions = new StringEventLog("Internal exceptions");
+    _redefinitions = new StringEventLog("Classes redefined");
     _deopt_messages = new StringEventLog("Deoptimization events");
   }
 }

src/share/vm/utilities/events.hpp

 /*
- * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2017, 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
@@ -186,6 +186,9 @@ class Events : AllStatic {
   // Deoptization related messages
   static StringEventLog* _deopt_messages;
 
+  // Redefinition related messages
+  static StringEventLog* _redefinitions;
+
  public:
   static void print_all(outputStream* out);
 
@@ -198,6 +201,8 @@ class Events : AllStatic {
   // Log exception related message
   static void log_exception(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
 
+  static void log_redefinition(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
+
   static void log_deopt_message(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
 
   // Register default loggers
@@ -222,6 +227,15 @@ inline void Events::log_exception(Thread* thread, const char* format, ...) {
   }
 }
 
+inline void Events::log_redefinition(Thread* thread, const char* format, ...) {
+  if (LogEvents) {
+    va_list ap;
+    va_start(ap, format);
+    _redefinitions->logv(thread, format, ap);
+    va_end(ap);
+  }
+}
+
 inline void Events::log_deopt_message(Thread* thread, const char* format, ...) {
   if (LogEvents) {
     va_list ap;