1 /*
   2  * Copyright (c) 2012, 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 "jni.h"
  27 #include "classfile/javaClasses.hpp"
  28 #include "classfile/symbolTable.hpp"
  29 #include "classfile/systemDictionary.hpp"
  30 #include "jfr/jni/jfrJavaSupport.hpp"
  31 #include "jfr/recorder/jfrRecorder.hpp"
  32 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
  33 #include "jfr/recorder/service/jfrRecorderThread.hpp"
  34 #include "memory/resourceArea.hpp"
  35 #include "memory/universe.hpp"
  36 #include "runtime/handles.inline.hpp"
  37 #include "runtime/mutexLocker.hpp"
  38 #include "runtime/thread.inline.hpp"
  39 #include "utilities/preserveException.hpp"
  40 #include "utilities/macros.hpp"
  41 
  42 static Thread* start_thread(instanceHandle thread_oop, ThreadFunction proc, TRAPS) {
  43   assert(thread_oop.not_null(), "invariant");
  44   assert(proc != NULL, "invariant");
  45 
  46   bool allocation_failed = false;
  47   JavaThread* new_thread = NULL;
  48   {
  49     MutexLocker mu(Threads_lock);
  50     new_thread = new JavaThread(proc);
  51     // At this point it may be possible that no
  52     // osthread was created for the JavaThread due to lack of memory.
  53     if (new_thread == NULL || new_thread->osthread() == NULL) {
  54       delete new_thread;
  55       allocation_failed = true;
  56     } else {
  57       java_lang_Thread::set_thread(thread_oop(), new_thread);
  58       java_lang_Thread::set_priority(thread_oop(), NormPriority);
  59       java_lang_Thread::set_daemon(thread_oop());
  60       new_thread->set_threadObj(thread_oop());
  61       Threads::add(new_thread);
  62     }
  63   }
  64   if (allocation_failed) {
  65     JfrJavaSupport::throw_out_of_memory_error("Unable to create native recording thread for JFR", CHECK_NULL);
  66   }
  67 
  68   Thread::start(new_thread);
  69   return new_thread;
  70 }
  71 
  72 JfrPostBox* JfrRecorderThread::_post_box = NULL;
  73 
  74 JfrPostBox& JfrRecorderThread::post_box() {
  75   return *_post_box;
  76 }
  77 
  78 // defined in JfrRecorderThreadLoop.cpp
  79 void recorderthread_entry(JavaThread*, Thread*);
  80 
  81 bool JfrRecorderThread::start(JfrCheckpointManager* cp_manager, JfrPostBox* post_box, TRAPS) {
  82   assert(cp_manager != NULL, "invariant");
  83   assert(post_box != NULL, "invariant");
  84   _post_box = post_box;
  85 
  86   static const char klass[] = "jdk/jfr/internal/JVMUpcalls";
  87   static const char method[] = "createRecorderThread";
  88   static const char signature[] = "(Ljava/lang/ThreadGroup;Ljava/lang/ClassLoader;)Ljava/lang/Thread;";
  89 
  90   JavaValue result(T_OBJECT);
  91   JfrJavaArguments create_thread_args(&result, klass, method, signature, CHECK_false);
  92 
  93   // arguments
  94   create_thread_args.push_oop(Universe::system_thread_group());
  95   create_thread_args.push_oop(SystemDictionary::java_system_loader());
  96 
  97   JfrJavaSupport::call_static(&create_thread_args, CHECK_false);
  98   instanceHandle h_thread_oop(THREAD, (instanceOop)result.get_jobject());
  99   assert(h_thread_oop.not_null(), "invariant");
 100   // attempt thread start
 101   const Thread* const t = start_thread(h_thread_oop, recorderthread_entry,THREAD);
 102   if (!HAS_PENDING_EXCEPTION) {
 103     cp_manager->register_service_thread(t);
 104     return true;
 105   }
 106   assert(HAS_PENDING_EXCEPTION, "invariant");
 107   // Start failed, remove the thread from the system thread group
 108   JavaValue void_result(T_VOID);
 109   JfrJavaArguments remove_thread_args(&void_result);
 110   remove_thread_args.set_klass(SystemDictionary::ThreadGroup_klass());
 111   remove_thread_args.set_name(vmSymbols::remove_method_name());
 112   remove_thread_args.set_signature(vmSymbols::thread_void_signature());
 113   remove_thread_args.set_receiver(Universe::system_thread_group());
 114   remove_thread_args.push_oop(h_thread_oop());
 115   CautiouslyPreserveExceptionMark cpe(THREAD);
 116   JfrJavaSupport::call_special(&remove_thread_args, THREAD);
 117   return false;
 118 }