1 /*
   2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaClasses.hpp"
  27 #include "classfile/symbolTable.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "jfr/jni/jfrJavaSupport.hpp"
  30 #include "jfr/jni/jfrUpcalls.hpp"
  31 #include "jfr/support/jfrEventClass.hpp"
  32 #include "memory/oopFactory.hpp"
  33 #include "oops/oop.inline.hpp"
  34 #include "oops/typeArrayKlass.hpp"
  35 #include "oops/typeArrayOop.hpp"
  36 #include "runtime/handles.inline.hpp"
  37 #include "runtime/os.hpp"
  38 #include "runtime/thread.inline.hpp"
  39 #include "utilities/exceptions.hpp"
  40 
  41 static Symbol* jvm_upcalls_class_sym = NULL;
  42 static Symbol* on_retransform_method_sym = NULL;
  43 static Symbol* on_retransform_signature_sym = NULL;
  44 static Symbol* bytes_for_eager_instrumentation_sym = NULL;
  45 static Symbol* bytes_for_eager_instrumentation_sig_sym = NULL;
  46 
  47 static bool initialize(TRAPS) {
  48   static bool initialized = false;
  49   if (!initialized) {
  50     DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
  51     jvm_upcalls_class_sym = SymbolTable::new_permanent_symbol("jdk/jfr/internal/JVMUpcalls", CHECK_false);
  52     on_retransform_method_sym = SymbolTable::new_permanent_symbol("onRetransform", CHECK_false);
  53     on_retransform_signature_sym = SymbolTable::new_permanent_symbol("(JZLjava/lang/Class;[B)[B", CHECK_false);
  54     bytes_for_eager_instrumentation_sym = SymbolTable::new_permanent_symbol("bytesForEagerInstrumentation", CHECK_false);
  55     bytes_for_eager_instrumentation_sig_sym = SymbolTable::new_permanent_symbol("(JZLjava/lang/Class;[B)[B", THREAD);
  56     initialized = bytes_for_eager_instrumentation_sig_sym != NULL;
  57   }
  58   return initialized;
  59 }
  60 
  61 static const typeArrayOop invoke(jlong trace_id,
  62                                  jboolean force_instrumentation,
  63                                  jclass class_being_redefined,
  64                                  jint class_data_len,
  65                                  const unsigned char* class_data,
  66                                  Symbol* method_sym,
  67                                  Symbol* signature_sym,
  68                                  jint& new_bytes_length,
  69                                  TRAPS) {
  70   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
  71   const Klass* klass = SystemDictionary::resolve_or_fail(jvm_upcalls_class_sym, true, CHECK_NULL);
  72   assert(klass != NULL, "invariant");
  73   typeArrayOop old_byte_array = oopFactory::new_byteArray(class_data_len, CHECK_NULL);
  74   memcpy(old_byte_array->byte_at_addr(0), class_data, class_data_len);
  75   JavaValue result(T_OBJECT);
  76   JfrJavaArguments args(&result, klass, method_sym, signature_sym);
  77   args.push_long(trace_id);
  78   args.push_int(force_instrumentation);
  79   args.push_jobject(class_being_redefined);
  80   args.push_oop(old_byte_array);
  81   JfrJavaSupport::call_static(&args, THREAD);
  82   if (HAS_PENDING_EXCEPTION) {
  83     if (true) tty->print_cr("JfrUpcall failed");
  84     return NULL;
  85   }
  86   // The result should be a [B
  87   const oop res = (oop)result.get_jobject();
  88   assert(res != NULL, "invariant");
  89   assert(res->is_typeArray(), "invariant");
  90   assert(TypeArrayKlass::cast(res->klass())->element_type() == T_BYTE, "invariant");
  91   const typeArrayOop new_byte_array = typeArrayOop(res);
  92   new_bytes_length = (jint)new_byte_array->length();
  93   return new_byte_array;
  94 }
  95 
  96 static const size_t ERROR_MSG_BUFFER_SIZE = 256;
  97 static void log_error_and_throw_oom(jint new_bytes_length, TRAPS) {
  98   char error_buffer[ERROR_MSG_BUFFER_SIZE];
  99   jio_snprintf(error_buffer, ERROR_MSG_BUFFER_SIZE,
 100     "Thread local allocation (native) for " SIZE_FORMAT " bytes failed in JfrUpcalls", (size_t)new_bytes_length);
 101   if (true) tty->print_cr("%s", error_buffer);
 102   JfrJavaSupport::throw_out_of_memory_error(error_buffer, CHECK);
 103 }
 104 
 105 void JfrUpcalls::on_retransform(jlong trace_id,
 106                                 jclass class_being_redefined,
 107                                 jint class_data_len,
 108                                 const unsigned char* class_data,
 109                                 jint* new_class_data_len,
 110                                 unsigned char** new_class_data,
 111                                 TRAPS) {
 112   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
 113   assert(class_being_redefined != NULL, "invariant");
 114   assert(class_data != NULL, "invariant");
 115   assert(new_class_data_len != NULL, "invariant");
 116   assert(new_class_data != NULL, "invariant");
 117   if (!JdkJfrEvent::is_visible(class_being_redefined)) {
 118     return;
 119   }
 120   jint new_bytes_length = 0;
 121   initialize(THREAD);
 122   const typeArrayOop new_byte_array = invoke(trace_id,
 123                                              false,
 124                                              class_being_redefined,
 125                                              class_data_len,
 126                                              class_data,
 127                                              on_retransform_method_sym,
 128                                              on_retransform_signature_sym,
 129                                              new_bytes_length,
 130                                              CHECK);
 131   assert(new_byte_array != NULL, "invariant");
 132   assert(new_bytes_length > 0, "invariant");
 133   // memory space must be malloced as mtInternal
 134   // as it will be deallocated by JVMTI routines
 135   unsigned char* const new_bytes = (unsigned char* const)os::malloc(new_bytes_length, mtInternal);
 136   if (new_bytes == NULL) {
 137     log_error_and_throw_oom(new_bytes_length, THREAD); // unwinds
 138   }
 139   assert(new_bytes != NULL, "invariant");
 140   memcpy(new_bytes, new_byte_array->byte_at_addr(0), (size_t)new_bytes_length);
 141   *new_class_data_len = new_bytes_length;
 142   *new_class_data = new_bytes;
 143 }
 144 
 145 void JfrUpcalls::new_bytes_eager_instrumentation(jlong trace_id,
 146                                                  jboolean force_instrumentation,
 147                                                  jclass super,
 148                                                  jint class_data_len,
 149                                                  const unsigned char* class_data,
 150                                                  jint* new_class_data_len,
 151                                                  unsigned char** new_class_data,
 152                                                  TRAPS) {
 153   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
 154   assert(super != NULL, "invariant");
 155   assert(class_data != NULL, "invariant");
 156   assert(new_class_data_len != NULL, "invariant");
 157   assert(new_class_data != NULL, "invariant");
 158   jint new_bytes_length = 0;
 159   initialize(THREAD);
 160   const typeArrayOop new_byte_array = invoke(trace_id,
 161                                              force_instrumentation,
 162                                              super,
 163                                              class_data_len,
 164                                              class_data,
 165                                              bytes_for_eager_instrumentation_sym,
 166                                              bytes_for_eager_instrumentation_sig_sym,
 167                                              new_bytes_length,
 168                                              CHECK);
 169   assert(new_byte_array != NULL, "invariant");
 170   assert(new_bytes_length > 0, "invariant");
 171   unsigned char* const new_bytes = NEW_RESOURCE_ARRAY_IN_THREAD_RETURN_NULL(THREAD, unsigned char, new_bytes_length);
 172   if (new_bytes == NULL) {
 173     log_error_and_throw_oom(new_bytes_length, THREAD); // this unwinds
 174   }
 175   assert(new_bytes != NULL, "invariant");
 176   memcpy(new_bytes, new_byte_array->byte_at_addr(0), (size_t)new_bytes_length);
 177   *new_class_data_len = new_bytes_length;
 178   *new_class_data = new_bytes;
 179 }
 180 
 181 instanceKlassHandle JfrUpcalls::load_event_handler_proxy_class(TRAPS) {
 182   JavaValue result(T_OBJECT);
 183   JfrJavaArguments call_args(&result, "jdk/jfr/internal/JVMUpcalls",
 184           "getEventHandlerProxyClass", "()Ljava/lang/Class;", CHECK_NULL);
 185   JfrJavaSupport::call_static(&call_args, CHECK_NULL);
 186   assert(result.get_type() == T_OBJECT, "invariant");
 187   instanceHandle h_java_proxy(THREAD, (instanceOop)result.get_jobject());
 188   assert(h_java_proxy.not_null(), "invariant");
 189   return java_lang_Class::as_Klass(h_java_proxy());
 190 }