view src/share/vm/memory/oopFactory.cpp @ 1716:be3f9c242c9d

6948538: CMS: BOT walkers can fall into object allocation and initialization cracks Summary: GC workers now recognize an intermediate transient state of blocks which are allocated but have not yet completed initialization. blk_start() calls do not attempt to determine the size of a block in the transient state, rather waiting for the block to become initialized so that it is safe to query its size. Audited and ensured the order of initialization of object fields (klass, free bit and size) to respect block state transition protocol. Also included some new assertion checking code enabled in debug mode. Reviewed-by: chrisphi, johnc, poonam
author ysr
date Mon, 16 Aug 2010 15:58:42 -0700
parents c18cbe5936b8
children f95d63e2154a
line wrap: on
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/*
 * Copyright (c) 1997, 2009, 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.
 *
 */

# include "incls/_precompiled.incl"
# include "incls/_oopFactory.cpp.incl"


typeArrayOop oopFactory::new_charArray(const char* utf8_str, TRAPS) {
  int length = utf8_str == NULL ? 0 : UTF8::unicode_length(utf8_str);
  typeArrayOop result = new_charArray(length, CHECK_NULL);
  if (length > 0) {
    UTF8::convert_to_unicode(utf8_str, result->char_at_addr(0), length);
  }
  return result;
}

typeArrayOop oopFactory::new_permanent_charArray(int length, TRAPS) {
  return typeArrayKlass::cast(Universe::charArrayKlassObj())->allocate_permanent(length, THREAD);
}

typeArrayOop oopFactory::new_permanent_byteArray(int length, TRAPS) {
  return typeArrayKlass::cast(Universe::byteArrayKlassObj())->allocate_permanent(length, THREAD);
}


typeArrayOop oopFactory::new_permanent_shortArray(int length, TRAPS) {
  return typeArrayKlass::cast(Universe::shortArrayKlassObj())->allocate_permanent(length, THREAD);
}


typeArrayOop oopFactory::new_permanent_intArray(int length, TRAPS) {
  return typeArrayKlass::cast(Universe::intArrayKlassObj())->allocate_permanent(length, THREAD);
}


typeArrayOop oopFactory::new_typeArray(BasicType type, int length, TRAPS) {
  klassOop type_asKlassOop = Universe::typeArrayKlassObj(type);
  typeArrayKlass* type_asArrayKlass = typeArrayKlass::cast(type_asKlassOop);
  typeArrayOop result = type_asArrayKlass->allocate(length, THREAD);
  return result;
}


objArrayOop oopFactory::new_objArray(klassOop klass, int length, TRAPS) {
  assert(klass->is_klass(), "must be instance class");
  if (klass->klass_part()->oop_is_array()) {
    return ((arrayKlass*)klass->klass_part())->allocate_arrayArray(1, length, THREAD);
  } else {
    assert (klass->klass_part()->oop_is_instance(), "new object array with klass not an instanceKlass");
    return ((instanceKlass*)klass->klass_part())->allocate_objArray(1, length, THREAD);
  }
}

objArrayOop oopFactory::new_system_objArray(int length, TRAPS) {
  int size = objArrayOopDesc::object_size(length);
  KlassHandle klass (THREAD, Universe::systemObjArrayKlassObj());
  objArrayOop o = (objArrayOop)
    Universe::heap()->permanent_array_allocate(klass, size, length, CHECK_NULL);
  // initialization not needed, allocated cleared
  return o;
}


constantPoolOop oopFactory::new_constantPool(int length,
                                             bool is_conc_safe,
                                             TRAPS) {
  constantPoolKlass* ck = constantPoolKlass::cast(Universe::constantPoolKlassObj());
  return ck->allocate(length, is_conc_safe, CHECK_NULL);
}


constantPoolCacheOop oopFactory::new_constantPoolCache(int length,
                                                       bool is_conc_safe,
                                                       TRAPS) {
  constantPoolCacheKlass* ck = constantPoolCacheKlass::cast(Universe::constantPoolCacheKlassObj());
  return ck->allocate(length, is_conc_safe, CHECK_NULL);
}


klassOop oopFactory::new_instanceKlass(int vtable_len, int itable_len,
                                       int static_field_size,
                                       unsigned int nonstatic_oop_map_count,
                                       ReferenceType rt, TRAPS) {
  instanceKlassKlass* ikk = instanceKlassKlass::cast(Universe::instanceKlassKlassObj());
  return ikk->allocate_instance_klass(vtable_len, itable_len, static_field_size, nonstatic_oop_map_count, rt, CHECK_NULL);
}


constMethodOop oopFactory::new_constMethod(int byte_code_size,
                                           int compressed_line_number_size,
                                           int localvariable_table_length,
                                           int checked_exceptions_length,
                                           bool is_conc_safe,
                                           TRAPS) {
  klassOop cmkObj = Universe::constMethodKlassObj();
  constMethodKlass* cmk = constMethodKlass::cast(cmkObj);
  return cmk->allocate(byte_code_size, compressed_line_number_size,
                       localvariable_table_length, checked_exceptions_length,
                       is_conc_safe,
                       CHECK_NULL);
}


methodOop oopFactory::new_method(int byte_code_size, AccessFlags access_flags,
                                 int compressed_line_number_size,
                                 int localvariable_table_length,
                                 int checked_exceptions_length,
                                 bool is_conc_safe,
                                 TRAPS) {
  methodKlass* mk = methodKlass::cast(Universe::methodKlassObj());
  assert(!access_flags.is_native() || byte_code_size == 0,
         "native methods should not contain byte codes");
  constMethodOop cm = new_constMethod(byte_code_size,
                                      compressed_line_number_size,
                                      localvariable_table_length,
                                      checked_exceptions_length,
                                      is_conc_safe, CHECK_NULL);
  constMethodHandle rw(THREAD, cm);
  return mk->allocate(rw, access_flags, CHECK_NULL);
}


methodDataOop oopFactory::new_methodData(methodHandle method, TRAPS) {
  methodDataKlass* mdk = methodDataKlass::cast(Universe::methodDataKlassObj());
  return mdk->allocate(method, CHECK_NULL);
}


compiledICHolderOop oopFactory::new_compiledICHolder(methodHandle method, KlassHandle klass, TRAPS) {
  compiledICHolderKlass* ck = (compiledICHolderKlass*) Universe::compiledICHolderKlassObj()->klass_part();
  compiledICHolderOop c = ck->allocate(CHECK_NULL);
  c->set_holder_method(method());
  c->set_holder_klass(klass());
  return c;
}