hotspot/src/share/vm/prims/jvmtiUtil.hpp
author ysr
Thu, 03 Dec 2009 15:01:57 -0800
changeset 4461 c17c526d36ef
parent 1 489c9b5090e2
child 5547 f4b087cbb361
permissions -rw-r--r--
6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa

/*
 * Copyright 1999-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

///////////////////////////////////////////////////////////////
//
// class JvmtiUtil
//
// class for miscellaneous jvmti utility static methods
//

class JvmtiUtil : AllStatic {

  static ResourceArea* _single_threaded_resource_area;

  static const char* _error_names[];
  static const bool  _event_threaded[];

public:

  static ResourceArea* single_threaded_resource_area();

  static const char* error_name(int num)    { return _error_names[num]; }    // To Do: add range checking

  static const bool has_event_capability(jvmtiEvent event_type, const jvmtiCapabilities* capabilities_ptr);

  static const bool  event_threaded(int num) {
    if (num >= JVMTI_MIN_EVENT_TYPE_VAL && num <= JVMTI_MAX_EVENT_TYPE_VAL) {
      return _event_threaded[num];
    }
    if (num >= EXT_MIN_EVENT_TYPE_VAL && num <= EXT_MAX_EVENT_TYPE_VAL) {
      return false;
    }
    ShouldNotReachHere();
    return false;
  }
};


///////////////////////////////////////////////////////////////
//
// class SafeResourceMark
//
// ResourceMarks that work before threads exist
//

class SafeResourceMark : public ResourceMark {

  ResourceArea* safe_resource_area() {
    Thread* thread;

    if (Threads::number_of_threads() == 0) {
      return JvmtiUtil::single_threaded_resource_area();
    }
    thread = ThreadLocalStorage::thread();
    if (thread == NULL) {
      return JvmtiUtil::single_threaded_resource_area();
    }
    return thread->resource_area();
  }

 public:

  SafeResourceMark() : ResourceMark(safe_resource_area()) {}

};