src/share/vm/memory/universe.cpp

Wed, 13 Jan 2010 15:26:39 -0800

author
ysr
date
Wed, 13 Jan 2010 15:26:39 -0800
changeset 1601
7b0e9cba0307
parent 1577
4ce7240d622c
child 1862
cd5dbf694d45
permissions
-rw-r--r--

6896647: card marks can be deferred too long
Summary: Deferred card marks are now flushed during the gc prologue. Parallel[Scavege,OldGC] and SerialGC no longer defer card marks generated by COMPILER2 as a result of ReduceInitialCardMarks. For these cases, introduced a diagnostic option to defer the card marks, only for the purposes of testing and diagnostics. CMS and G1 continue to defer card marks. Potential performance concern related to single-threaded flushing of deferred card marks in the gc prologue will be addressed in the future.
Reviewed-by: never, johnc

     1 /*
     2  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 # include "incls/_precompiled.incl"
    26 # include "incls/_universe.cpp.incl"
    28 // Known objects
    29 klassOop Universe::_boolArrayKlassObj                 = NULL;
    30 klassOop Universe::_byteArrayKlassObj                 = NULL;
    31 klassOop Universe::_charArrayKlassObj                 = NULL;
    32 klassOop Universe::_intArrayKlassObj                  = NULL;
    33 klassOop Universe::_shortArrayKlassObj                = NULL;
    34 klassOop Universe::_longArrayKlassObj                 = NULL;
    35 klassOop Universe::_singleArrayKlassObj               = NULL;
    36 klassOop Universe::_doubleArrayKlassObj               = NULL;
    37 klassOop Universe::_typeArrayKlassObjs[T_VOID+1]      = { NULL /*, NULL...*/ };
    38 klassOop Universe::_objectArrayKlassObj               = NULL;
    39 klassOop Universe::_symbolKlassObj                    = NULL;
    40 klassOop Universe::_methodKlassObj                    = NULL;
    41 klassOop Universe::_constMethodKlassObj               = NULL;
    42 klassOop Universe::_methodDataKlassObj                = NULL;
    43 klassOop Universe::_klassKlassObj                     = NULL;
    44 klassOop Universe::_arrayKlassKlassObj                = NULL;
    45 klassOop Universe::_objArrayKlassKlassObj             = NULL;
    46 klassOop Universe::_typeArrayKlassKlassObj            = NULL;
    47 klassOop Universe::_instanceKlassKlassObj             = NULL;
    48 klassOop Universe::_constantPoolKlassObj              = NULL;
    49 klassOop Universe::_constantPoolCacheKlassObj         = NULL;
    50 klassOop Universe::_compiledICHolderKlassObj          = NULL;
    51 klassOop Universe::_systemObjArrayKlassObj            = NULL;
    52 oop Universe::_int_mirror                             = NULL;
    53 oop Universe::_float_mirror                           = NULL;
    54 oop Universe::_double_mirror                          = NULL;
    55 oop Universe::_byte_mirror                            = NULL;
    56 oop Universe::_bool_mirror                            = NULL;
    57 oop Universe::_char_mirror                            = NULL;
    58 oop Universe::_long_mirror                            = NULL;
    59 oop Universe::_short_mirror                           = NULL;
    60 oop Universe::_void_mirror                            = NULL;
    61 oop Universe::_mirrors[T_VOID+1]                      = { NULL /*, NULL...*/ };
    62 oop Universe::_main_thread_group                      = NULL;
    63 oop Universe::_system_thread_group                    = NULL;
    64 typeArrayOop Universe::_the_empty_byte_array          = NULL;
    65 typeArrayOop Universe::_the_empty_short_array         = NULL;
    66 typeArrayOop Universe::_the_empty_int_array           = NULL;
    67 objArrayOop Universe::_the_empty_system_obj_array     = NULL;
    68 objArrayOop Universe::_the_empty_class_klass_array    = NULL;
    69 objArrayOop Universe::_the_array_interfaces_array     = NULL;
    70 oop Universe::_the_null_string                        = NULL;
    71 oop Universe::_the_min_jint_string                   = NULL;
    72 LatestMethodOopCache* Universe::_finalizer_register_cache = NULL;
    73 LatestMethodOopCache* Universe::_loader_addClass_cache    = NULL;
    74 ActiveMethodOopsCache* Universe::_reflect_invoke_cache    = NULL;
    75 oop Universe::_out_of_memory_error_java_heap          = NULL;
    76 oop Universe::_out_of_memory_error_perm_gen           = NULL;
    77 oop Universe::_out_of_memory_error_array_size         = NULL;
    78 oop Universe::_out_of_memory_error_gc_overhead_limit  = NULL;
    79 objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
    80 volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
    81 bool Universe::_verify_in_progress                    = false;
    82 oop Universe::_null_ptr_exception_instance            = NULL;
    83 oop Universe::_arithmetic_exception_instance          = NULL;
    84 oop Universe::_virtual_machine_error_instance         = NULL;
    85 oop Universe::_vm_exception                           = NULL;
    86 oop Universe::_emptySymbol                            = NULL;
    88 // These variables are guarded by FullGCALot_lock.
    89 debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
    90 debug_only(int Universe::_fullgc_alot_dummy_next      = 0;)
    93 // Heap
    94 int             Universe::_verify_count = 0;
    96 int             Universe::_base_vtable_size = 0;
    97 bool            Universe::_bootstrapping = false;
    98 bool            Universe::_fully_initialized = false;
   100 size_t          Universe::_heap_capacity_at_last_gc;
   101 size_t          Universe::_heap_used_at_last_gc = 0;
   103 CollectedHeap*  Universe::_collectedHeap = NULL;
   105 NarrowOopStruct Universe::_narrow_oop = { NULL, 0, true };
   108 void Universe::basic_type_classes_do(void f(klassOop)) {
   109   f(boolArrayKlassObj());
   110   f(byteArrayKlassObj());
   111   f(charArrayKlassObj());
   112   f(intArrayKlassObj());
   113   f(shortArrayKlassObj());
   114   f(longArrayKlassObj());
   115   f(singleArrayKlassObj());
   116   f(doubleArrayKlassObj());
   117 }
   120 void Universe::system_classes_do(void f(klassOop)) {
   121   f(symbolKlassObj());
   122   f(methodKlassObj());
   123   f(constMethodKlassObj());
   124   f(methodDataKlassObj());
   125   f(klassKlassObj());
   126   f(arrayKlassKlassObj());
   127   f(objArrayKlassKlassObj());
   128   f(typeArrayKlassKlassObj());
   129   f(instanceKlassKlassObj());
   130   f(constantPoolKlassObj());
   131   f(systemObjArrayKlassObj());
   132 }
   134 void Universe::oops_do(OopClosure* f, bool do_all) {
   136   f->do_oop((oop*) &_int_mirror);
   137   f->do_oop((oop*) &_float_mirror);
   138   f->do_oop((oop*) &_double_mirror);
   139   f->do_oop((oop*) &_byte_mirror);
   140   f->do_oop((oop*) &_bool_mirror);
   141   f->do_oop((oop*) &_char_mirror);
   142   f->do_oop((oop*) &_long_mirror);
   143   f->do_oop((oop*) &_short_mirror);
   144   f->do_oop((oop*) &_void_mirror);
   146   // It's important to iterate over these guys even if they are null,
   147   // since that's how shared heaps are restored.
   148   for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
   149     f->do_oop((oop*) &_mirrors[i]);
   150   }
   151   assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
   153   // %%% Consider moving those "shared oops" over here with the others.
   154   f->do_oop((oop*)&_boolArrayKlassObj);
   155   f->do_oop((oop*)&_byteArrayKlassObj);
   156   f->do_oop((oop*)&_charArrayKlassObj);
   157   f->do_oop((oop*)&_intArrayKlassObj);
   158   f->do_oop((oop*)&_shortArrayKlassObj);
   159   f->do_oop((oop*)&_longArrayKlassObj);
   160   f->do_oop((oop*)&_singleArrayKlassObj);
   161   f->do_oop((oop*)&_doubleArrayKlassObj);
   162   f->do_oop((oop*)&_objectArrayKlassObj);
   163   {
   164     for (int i = 0; i < T_VOID+1; i++) {
   165       if (_typeArrayKlassObjs[i] != NULL) {
   166         assert(i >= T_BOOLEAN, "checking");
   167         f->do_oop((oop*)&_typeArrayKlassObjs[i]);
   168       } else if (do_all) {
   169         f->do_oop((oop*)&_typeArrayKlassObjs[i]);
   170       }
   171     }
   172   }
   173   f->do_oop((oop*)&_symbolKlassObj);
   174   f->do_oop((oop*)&_methodKlassObj);
   175   f->do_oop((oop*)&_constMethodKlassObj);
   176   f->do_oop((oop*)&_methodDataKlassObj);
   177   f->do_oop((oop*)&_klassKlassObj);
   178   f->do_oop((oop*)&_arrayKlassKlassObj);
   179   f->do_oop((oop*)&_objArrayKlassKlassObj);
   180   f->do_oop((oop*)&_typeArrayKlassKlassObj);
   181   f->do_oop((oop*)&_instanceKlassKlassObj);
   182   f->do_oop((oop*)&_constantPoolKlassObj);
   183   f->do_oop((oop*)&_constantPoolCacheKlassObj);
   184   f->do_oop((oop*)&_compiledICHolderKlassObj);
   185   f->do_oop((oop*)&_systemObjArrayKlassObj);
   186   f->do_oop((oop*)&_the_empty_byte_array);
   187   f->do_oop((oop*)&_the_empty_short_array);
   188   f->do_oop((oop*)&_the_empty_int_array);
   189   f->do_oop((oop*)&_the_empty_system_obj_array);
   190   f->do_oop((oop*)&_the_empty_class_klass_array);
   191   f->do_oop((oop*)&_the_array_interfaces_array);
   192   f->do_oop((oop*)&_the_null_string);
   193   f->do_oop((oop*)&_the_min_jint_string);
   194   _finalizer_register_cache->oops_do(f);
   195   _loader_addClass_cache->oops_do(f);
   196   _reflect_invoke_cache->oops_do(f);
   197   f->do_oop((oop*)&_out_of_memory_error_java_heap);
   198   f->do_oop((oop*)&_out_of_memory_error_perm_gen);
   199   f->do_oop((oop*)&_out_of_memory_error_array_size);
   200   f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
   201   if (_preallocated_out_of_memory_error_array != (oop)NULL) {   // NULL when DumpSharedSpaces
   202     f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
   203   }
   204   f->do_oop((oop*)&_null_ptr_exception_instance);
   205   f->do_oop((oop*)&_arithmetic_exception_instance);
   206   f->do_oop((oop*)&_virtual_machine_error_instance);
   207   f->do_oop((oop*)&_main_thread_group);
   208   f->do_oop((oop*)&_system_thread_group);
   209   f->do_oop((oop*)&_vm_exception);
   210   f->do_oop((oop*)&_emptySymbol);
   211   debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
   212 }
   215 void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
   216   if (size < alignment || size % alignment != 0) {
   217     ResourceMark rm;
   218     stringStream st;
   219     st.print("Size of %s (%ld bytes) must be aligned to %ld bytes", name, size, alignment);
   220     char* error = st.as_string();
   221     vm_exit_during_initialization(error);
   222   }
   223 }
   226 void Universe::genesis(TRAPS) {
   227   ResourceMark rm;
   228   { FlagSetting fs(_bootstrapping, true);
   230     { MutexLocker mc(Compile_lock);
   232       // determine base vtable size; without that we cannot create the array klasses
   233       compute_base_vtable_size();
   235       if (!UseSharedSpaces) {
   236         _klassKlassObj          = klassKlass::create_klass(CHECK);
   237         _arrayKlassKlassObj     = arrayKlassKlass::create_klass(CHECK);
   239         _objArrayKlassKlassObj  = objArrayKlassKlass::create_klass(CHECK);
   240         _instanceKlassKlassObj  = instanceKlassKlass::create_klass(CHECK);
   241         _typeArrayKlassKlassObj = typeArrayKlassKlass::create_klass(CHECK);
   243         _symbolKlassObj         = symbolKlass::create_klass(CHECK);
   245         _emptySymbol            = oopFactory::new_symbol("", CHECK);
   247         _boolArrayKlassObj      = typeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
   248         _charArrayKlassObj      = typeArrayKlass::create_klass(T_CHAR,    sizeof(jchar),    CHECK);
   249         _singleArrayKlassObj    = typeArrayKlass::create_klass(T_FLOAT,   sizeof(jfloat),   CHECK);
   250         _doubleArrayKlassObj    = typeArrayKlass::create_klass(T_DOUBLE,  sizeof(jdouble),  CHECK);
   251         _byteArrayKlassObj      = typeArrayKlass::create_klass(T_BYTE,    sizeof(jbyte),    CHECK);
   252         _shortArrayKlassObj     = typeArrayKlass::create_klass(T_SHORT,   sizeof(jshort),   CHECK);
   253         _intArrayKlassObj       = typeArrayKlass::create_klass(T_INT,     sizeof(jint),     CHECK);
   254         _longArrayKlassObj      = typeArrayKlass::create_klass(T_LONG,    sizeof(jlong),    CHECK);
   256         _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
   257         _typeArrayKlassObjs[T_CHAR]    = _charArrayKlassObj;
   258         _typeArrayKlassObjs[T_FLOAT]   = _singleArrayKlassObj;
   259         _typeArrayKlassObjs[T_DOUBLE]  = _doubleArrayKlassObj;
   260         _typeArrayKlassObjs[T_BYTE]    = _byteArrayKlassObj;
   261         _typeArrayKlassObjs[T_SHORT]   = _shortArrayKlassObj;
   262         _typeArrayKlassObjs[T_INT]     = _intArrayKlassObj;
   263         _typeArrayKlassObjs[T_LONG]    = _longArrayKlassObj;
   265         _methodKlassObj             = methodKlass::create_klass(CHECK);
   266         _constMethodKlassObj        = constMethodKlass::create_klass(CHECK);
   267         _methodDataKlassObj         = methodDataKlass::create_klass(CHECK);
   268         _constantPoolKlassObj       = constantPoolKlass::create_klass(CHECK);
   269         _constantPoolCacheKlassObj  = constantPoolCacheKlass::create_klass(CHECK);
   271         _compiledICHolderKlassObj   = compiledICHolderKlass::create_klass(CHECK);
   272         _systemObjArrayKlassObj     = objArrayKlassKlass::cast(objArrayKlassKlassObj())->allocate_system_objArray_klass(CHECK);
   274         _the_empty_byte_array       = oopFactory::new_permanent_byteArray(0, CHECK);
   275         _the_empty_short_array      = oopFactory::new_permanent_shortArray(0, CHECK);
   276         _the_empty_int_array        = oopFactory::new_permanent_intArray(0, CHECK);
   277         _the_empty_system_obj_array = oopFactory::new_system_objArray(0, CHECK);
   279         _the_array_interfaces_array = oopFactory::new_system_objArray(2, CHECK);
   280         _vm_exception               = oopFactory::new_symbol("vm exception holder", CHECK);
   281       } else {
   282         FileMapInfo *mapinfo = FileMapInfo::current_info();
   283         char* buffer = mapinfo->region_base(CompactingPermGenGen::md);
   284         void** vtbl_list = (void**)buffer;
   285         init_self_patching_vtbl_list(vtbl_list,
   286                                      CompactingPermGenGen::vtbl_list_size);
   287       }
   288     }
   290     vmSymbols::initialize(CHECK);
   292     SystemDictionary::initialize(CHECK);
   294     klassOop ok = SystemDictionary::Object_klass();
   296     _the_null_string            = StringTable::intern("null", CHECK);
   297     _the_min_jint_string       = StringTable::intern("-2147483648", CHECK);
   299     if (UseSharedSpaces) {
   300       // Verify shared interfaces array.
   301       assert(_the_array_interfaces_array->obj_at(0) ==
   302              SystemDictionary::Cloneable_klass(), "u3");
   303       assert(_the_array_interfaces_array->obj_at(1) ==
   304              SystemDictionary::Serializable_klass(), "u3");
   306       // Verify element klass for system obj array klass
   307       assert(objArrayKlass::cast(_systemObjArrayKlassObj)->element_klass() == ok, "u1");
   308       assert(objArrayKlass::cast(_systemObjArrayKlassObj)->bottom_klass() == ok, "u2");
   310       // Verify super class for the classes created above
   311       assert(Klass::cast(boolArrayKlassObj()     )->super() == ok, "u3");
   312       assert(Klass::cast(charArrayKlassObj()     )->super() == ok, "u3");
   313       assert(Klass::cast(singleArrayKlassObj()   )->super() == ok, "u3");
   314       assert(Klass::cast(doubleArrayKlassObj()   )->super() == ok, "u3");
   315       assert(Klass::cast(byteArrayKlassObj()     )->super() == ok, "u3");
   316       assert(Klass::cast(shortArrayKlassObj()    )->super() == ok, "u3");
   317       assert(Klass::cast(intArrayKlassObj()      )->super() == ok, "u3");
   318       assert(Klass::cast(longArrayKlassObj()     )->super() == ok, "u3");
   319       assert(Klass::cast(constantPoolKlassObj()  )->super() == ok, "u3");
   320       assert(Klass::cast(systemObjArrayKlassObj())->super() == ok, "u3");
   321     } else {
   322       // Set up shared interfaces array.  (Do this before supers are set up.)
   323       _the_array_interfaces_array->obj_at_put(0, SystemDictionary::Cloneable_klass());
   324       _the_array_interfaces_array->obj_at_put(1, SystemDictionary::Serializable_klass());
   326       // Set element klass for system obj array klass
   327       objArrayKlass::cast(_systemObjArrayKlassObj)->set_element_klass(ok);
   328       objArrayKlass::cast(_systemObjArrayKlassObj)->set_bottom_klass(ok);
   330       // Set super class for the classes created above
   331       Klass::cast(boolArrayKlassObj()     )->initialize_supers(ok, CHECK);
   332       Klass::cast(charArrayKlassObj()     )->initialize_supers(ok, CHECK);
   333       Klass::cast(singleArrayKlassObj()   )->initialize_supers(ok, CHECK);
   334       Klass::cast(doubleArrayKlassObj()   )->initialize_supers(ok, CHECK);
   335       Klass::cast(byteArrayKlassObj()     )->initialize_supers(ok, CHECK);
   336       Klass::cast(shortArrayKlassObj()    )->initialize_supers(ok, CHECK);
   337       Klass::cast(intArrayKlassObj()      )->initialize_supers(ok, CHECK);
   338       Klass::cast(longArrayKlassObj()     )->initialize_supers(ok, CHECK);
   339       Klass::cast(constantPoolKlassObj()  )->initialize_supers(ok, CHECK);
   340       Klass::cast(systemObjArrayKlassObj())->initialize_supers(ok, CHECK);
   341       Klass::cast(boolArrayKlassObj()     )->set_super(ok);
   342       Klass::cast(charArrayKlassObj()     )->set_super(ok);
   343       Klass::cast(singleArrayKlassObj()   )->set_super(ok);
   344       Klass::cast(doubleArrayKlassObj()   )->set_super(ok);
   345       Klass::cast(byteArrayKlassObj()     )->set_super(ok);
   346       Klass::cast(shortArrayKlassObj()    )->set_super(ok);
   347       Klass::cast(intArrayKlassObj()      )->set_super(ok);
   348       Klass::cast(longArrayKlassObj()     )->set_super(ok);
   349       Klass::cast(constantPoolKlassObj()  )->set_super(ok);
   350       Klass::cast(systemObjArrayKlassObj())->set_super(ok);
   351     }
   353     Klass::cast(boolArrayKlassObj()     )->append_to_sibling_list();
   354     Klass::cast(charArrayKlassObj()     )->append_to_sibling_list();
   355     Klass::cast(singleArrayKlassObj()   )->append_to_sibling_list();
   356     Klass::cast(doubleArrayKlassObj()   )->append_to_sibling_list();
   357     Klass::cast(byteArrayKlassObj()     )->append_to_sibling_list();
   358     Klass::cast(shortArrayKlassObj()    )->append_to_sibling_list();
   359     Klass::cast(intArrayKlassObj()      )->append_to_sibling_list();
   360     Klass::cast(longArrayKlassObj()     )->append_to_sibling_list();
   361     Klass::cast(constantPoolKlassObj()  )->append_to_sibling_list();
   362     Klass::cast(systemObjArrayKlassObj())->append_to_sibling_list();
   363   } // end of core bootstrapping
   365   // Initialize _objectArrayKlass after core bootstraping to make
   366   // sure the super class is set up properly for _objectArrayKlass.
   367   _objectArrayKlassObj = instanceKlass::
   368     cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
   369   // Add the class to the class hierarchy manually to make sure that
   370   // its vtable is initialized after core bootstrapping is completed.
   371   Klass::cast(_objectArrayKlassObj)->append_to_sibling_list();
   373   // Compute is_jdk version flags.
   374   // Only 1.3 or later has the java.lang.Shutdown class.
   375   // Only 1.4 or later has the java.lang.CharSequence interface.
   376   // Only 1.5 or later has the java.lang.management.MemoryUsage class.
   377   if (JDK_Version::is_partially_initialized()) {
   378     uint8_t jdk_version;
   379     klassOop k = SystemDictionary::resolve_or_null(
   380         vmSymbolHandles::java_lang_management_MemoryUsage(), THREAD);
   381     CLEAR_PENDING_EXCEPTION; // ignore exceptions
   382     if (k == NULL) {
   383       k = SystemDictionary::resolve_or_null(
   384           vmSymbolHandles::java_lang_CharSequence(), THREAD);
   385       CLEAR_PENDING_EXCEPTION; // ignore exceptions
   386       if (k == NULL) {
   387         k = SystemDictionary::resolve_or_null(
   388             vmSymbolHandles::java_lang_Shutdown(), THREAD);
   389         CLEAR_PENDING_EXCEPTION; // ignore exceptions
   390         if (k == NULL) {
   391           jdk_version = 2;
   392         } else {
   393           jdk_version = 3;
   394         }
   395       } else {
   396         jdk_version = 4;
   397       }
   398     } else {
   399       jdk_version = 5;
   400     }
   401     JDK_Version::fully_initialize(jdk_version);
   402   }
   404   #ifdef ASSERT
   405   if (FullGCALot) {
   406     // Allocate an array of dummy objects.
   407     // We'd like these to be at the bottom of the old generation,
   408     // so that when we free one and then collect,
   409     // (almost) the whole heap moves
   410     // and we find out if we actually update all the oops correctly.
   411     // But we can't allocate directly in the old generation,
   412     // so we allocate wherever, and hope that the first collection
   413     // moves these objects to the bottom of the old generation.
   414     // We can allocate directly in the permanent generation, so we do.
   415     int size;
   416     if (UseConcMarkSweepGC) {
   417       warning("Using +FullGCALot with concurrent mark sweep gc "
   418               "will not force all objects to relocate");
   419       size = FullGCALotDummies;
   420     } else {
   421       size = FullGCALotDummies * 2;
   422     }
   423     objArrayOop    naked_array = oopFactory::new_system_objArray(size, CHECK);
   424     objArrayHandle dummy_array(THREAD, naked_array);
   425     int i = 0;
   426     while (i < size) {
   427       if (!UseConcMarkSweepGC) {
   428         // Allocate dummy in old generation
   429         oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
   430         dummy_array->obj_at_put(i++, dummy);
   431       }
   432       // Allocate dummy in permanent generation
   433       oop dummy = instanceKlass::cast(SystemDictionary::Object_klass())->allocate_permanent_instance(CHECK);
   434       dummy_array->obj_at_put(i++, dummy);
   435     }
   436     {
   437       // Only modify the global variable inside the mutex.
   438       // If we had a race to here, the other dummy_array instances
   439       // and their elements just get dropped on the floor, which is fine.
   440       MutexLocker ml(FullGCALot_lock);
   441       if (_fullgc_alot_dummy_array == NULL) {
   442         _fullgc_alot_dummy_array = dummy_array();
   443       }
   444     }
   445     assert(i == _fullgc_alot_dummy_array->length(), "just checking");
   446   }
   447   #endif
   448 }
   451 static inline void add_vtable(void** list, int* n, Klass* o, int count) {
   452   list[(*n)++] = *(void**)&o->vtbl_value();
   453   guarantee((*n) <= count, "vtable list too small.");
   454 }
   457 void Universe::init_self_patching_vtbl_list(void** list, int count) {
   458   int n = 0;
   459   { klassKlass o;             add_vtable(list, &n, &o, count); }
   460   { arrayKlassKlass o;        add_vtable(list, &n, &o, count); }
   461   { objArrayKlassKlass o;     add_vtable(list, &n, &o, count); }
   462   { instanceKlassKlass o;     add_vtable(list, &n, &o, count); }
   463   { instanceKlass o;          add_vtable(list, &n, &o, count); }
   464   { instanceRefKlass o;       add_vtable(list, &n, &o, count); }
   465   { typeArrayKlassKlass o;    add_vtable(list, &n, &o, count); }
   466   { symbolKlass o;            add_vtable(list, &n, &o, count); }
   467   { typeArrayKlass o;         add_vtable(list, &n, &o, count); }
   468   { methodKlass o;            add_vtable(list, &n, &o, count); }
   469   { constMethodKlass o;       add_vtable(list, &n, &o, count); }
   470   { constantPoolKlass o;      add_vtable(list, &n, &o, count); }
   471   { constantPoolCacheKlass o; add_vtable(list, &n, &o, count); }
   472   { objArrayKlass o;          add_vtable(list, &n, &o, count); }
   473   { methodDataKlass o;        add_vtable(list, &n, &o, count); }
   474   { compiledICHolderKlass o;  add_vtable(list, &n, &o, count); }
   475 }
   478 class FixupMirrorClosure: public ObjectClosure {
   479  public:
   480   virtual void do_object(oop obj) {
   481     if (obj->is_klass()) {
   482       EXCEPTION_MARK;
   483       KlassHandle k(THREAD, klassOop(obj));
   484       // We will never reach the CATCH below since Exceptions::_throw will cause
   485       // the VM to exit if an exception is thrown during initialization
   486       java_lang_Class::create_mirror(k, CATCH);
   487       // This call unconditionally creates a new mirror for k,
   488       // and links in k's component_mirror field if k is an array.
   489       // If k is an objArray, k's element type must already have
   490       // a mirror.  In other words, this closure must process
   491       // the component type of an objArray k before it processes k.
   492       // This works because the permgen iterator presents arrays
   493       // and their component types in order of creation.
   494     }
   495   }
   496 };
   498 void Universe::initialize_basic_type_mirrors(TRAPS) {
   499   if (UseSharedSpaces) {
   500     assert(_int_mirror != NULL, "already loaded");
   501     assert(_void_mirror == _mirrors[T_VOID], "consistently loaded");
   502   } else {
   504     assert(_int_mirror==NULL, "basic type mirrors already initialized");
   505     _int_mirror     =
   506       java_lang_Class::create_basic_type_mirror("int",    T_INT, CHECK);
   507     _float_mirror   =
   508       java_lang_Class::create_basic_type_mirror("float",  T_FLOAT,   CHECK);
   509     _double_mirror  =
   510       java_lang_Class::create_basic_type_mirror("double", T_DOUBLE,  CHECK);
   511     _byte_mirror    =
   512       java_lang_Class::create_basic_type_mirror("byte",   T_BYTE, CHECK);
   513     _bool_mirror    =
   514       java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
   515     _char_mirror    =
   516       java_lang_Class::create_basic_type_mirror("char",   T_CHAR, CHECK);
   517     _long_mirror    =
   518       java_lang_Class::create_basic_type_mirror("long",   T_LONG, CHECK);
   519     _short_mirror   =
   520       java_lang_Class::create_basic_type_mirror("short",  T_SHORT,   CHECK);
   521     _void_mirror    =
   522       java_lang_Class::create_basic_type_mirror("void",   T_VOID, CHECK);
   524     _mirrors[T_INT]     = _int_mirror;
   525     _mirrors[T_FLOAT]   = _float_mirror;
   526     _mirrors[T_DOUBLE]  = _double_mirror;
   527     _mirrors[T_BYTE]    = _byte_mirror;
   528     _mirrors[T_BOOLEAN] = _bool_mirror;
   529     _mirrors[T_CHAR]    = _char_mirror;
   530     _mirrors[T_LONG]    = _long_mirror;
   531     _mirrors[T_SHORT]   = _short_mirror;
   532     _mirrors[T_VOID]    = _void_mirror;
   533     //_mirrors[T_OBJECT]  = instanceKlass::cast(_object_klass)->java_mirror();
   534     //_mirrors[T_ARRAY]   = instanceKlass::cast(_object_klass)->java_mirror();
   535   }
   536 }
   538 void Universe::fixup_mirrors(TRAPS) {
   539   // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
   540   // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
   541   // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
   542   // that the number of objects allocated at this point is very small.
   543   assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
   544   FixupMirrorClosure blk;
   545   Universe::heap()->permanent_object_iterate(&blk);
   546 }
   549 static bool has_run_finalizers_on_exit = false;
   551 void Universe::run_finalizers_on_exit() {
   552   if (has_run_finalizers_on_exit) return;
   553   has_run_finalizers_on_exit = true;
   555   // Called on VM exit. This ought to be run in a separate thread.
   556   if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
   557   {
   558     PRESERVE_EXCEPTION_MARK;
   559     KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
   560     JavaValue result(T_VOID);
   561     JavaCalls::call_static(
   562       &result,
   563       finalizer_klass,
   564       vmSymbolHandles::run_finalizers_on_exit_name(),
   565       vmSymbolHandles::void_method_signature(),
   566       THREAD
   567     );
   568     // Ignore any pending exceptions
   569     CLEAR_PENDING_EXCEPTION;
   570   }
   571 }
   574 // initialize_vtable could cause gc if
   575 // 1) we specified true to initialize_vtable and
   576 // 2) this ran after gc was enabled
   577 // In case those ever change we use handles for oops
   578 void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
   579   // init vtable of k and all subclasses
   580   Klass* ko = k_h()->klass_part();
   581   klassVtable* vt = ko->vtable();
   582   if (vt) vt->initialize_vtable(false, CHECK);
   583   if (ko->oop_is_instance()) {
   584     instanceKlass* ik = (instanceKlass*)ko;
   585     for (KlassHandle s_h(THREAD, ik->subklass()); s_h() != NULL; s_h = (THREAD, s_h()->klass_part()->next_sibling())) {
   586       reinitialize_vtable_of(s_h, CHECK);
   587     }
   588   }
   589 }
   592 void initialize_itable_for_klass(klassOop k, TRAPS) {
   593   instanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
   594 }
   597 void Universe::reinitialize_itables(TRAPS) {
   598   SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
   600 }
   603 bool Universe::on_page_boundary(void* addr) {
   604   return ((uintptr_t) addr) % os::vm_page_size() == 0;
   605 }
   608 bool Universe::should_fill_in_stack_trace(Handle throwable) {
   609   // never attempt to fill in the stack trace of preallocated errors that do not have
   610   // backtrace. These errors are kept alive forever and may be "re-used" when all
   611   // preallocated errors with backtrace have been consumed. Also need to avoid
   612   // a potential loop which could happen if an out of memory occurs when attempting
   613   // to allocate the backtrace.
   614   return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
   615           (throwable() != Universe::_out_of_memory_error_perm_gen)  &&
   616           (throwable() != Universe::_out_of_memory_error_array_size) &&
   617           (throwable() != Universe::_out_of_memory_error_gc_overhead_limit));
   618 }
   621 oop Universe::gen_out_of_memory_error(oop default_err) {
   622   // generate an out of memory error:
   623   // - if there is a preallocated error with backtrace available then return it wth
   624   //   a filled in stack trace.
   625   // - if there are no preallocated errors with backtrace available then return
   626   //   an error without backtrace.
   627   int next;
   628   if (_preallocated_out_of_memory_error_avail_count > 0) {
   629     next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
   630     assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
   631   } else {
   632     next = -1;
   633   }
   634   if (next < 0) {
   635     // all preallocated errors have been used.
   636     // return default
   637     return default_err;
   638   } else {
   639     // get the error object at the slot and set set it to NULL so that the
   640     // array isn't keeping it alive anymore.
   641     oop exc = preallocated_out_of_memory_errors()->obj_at(next);
   642     assert(exc != NULL, "slot has been used already");
   643     preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
   645     // use the message from the default error
   646     oop msg = java_lang_Throwable::message(default_err);
   647     assert(msg != NULL, "no message");
   648     java_lang_Throwable::set_message(exc, msg);
   650     // populate the stack trace and return it.
   651     java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
   652     return exc;
   653   }
   654 }
   656 static intptr_t non_oop_bits = 0;
   658 void* Universe::non_oop_word() {
   659   // Neither the high bits nor the low bits of this value is allowed
   660   // to look like (respectively) the high or low bits of a real oop.
   661   //
   662   // High and low are CPU-specific notions, but low always includes
   663   // the low-order bit.  Since oops are always aligned at least mod 4,
   664   // setting the low-order bit will ensure that the low half of the
   665   // word will never look like that of a real oop.
   666   //
   667   // Using the OS-supplied non-memory-address word (usually 0 or -1)
   668   // will take care of the high bits, however many there are.
   670   if (non_oop_bits == 0) {
   671     non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
   672   }
   674   return (void*)non_oop_bits;
   675 }
   677 jint universe_init() {
   678   assert(!Universe::_fully_initialized, "called after initialize_vtables");
   679   guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
   680          "LogHeapWordSize is incorrect.");
   681   guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
   682   guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
   683             "oop size is not not a multiple of HeapWord size");
   684   TraceTime timer("Genesis", TraceStartupTime);
   685   GC_locker::lock();  // do not allow gc during bootstrapping
   686   JavaClasses::compute_hard_coded_offsets();
   688   // Get map info from shared archive file.
   689   if (DumpSharedSpaces)
   690     UseSharedSpaces = false;
   692   FileMapInfo* mapinfo = NULL;
   693   if (UseSharedSpaces) {
   694     mapinfo = NEW_C_HEAP_OBJ(FileMapInfo);
   695     memset(mapinfo, 0, sizeof(FileMapInfo));
   697     // Open the shared archive file, read and validate the header. If
   698     // initialization files, shared spaces [UseSharedSpaces] are
   699     // disabled and the file is closed.
   701     if (mapinfo->initialize()) {
   702       FileMapInfo::set_current_info(mapinfo);
   703     } else {
   704       assert(!mapinfo->is_open() && !UseSharedSpaces,
   705              "archive file not closed or shared spaces not disabled.");
   706     }
   707   }
   709   jint status = Universe::initialize_heap();
   710   if (status != JNI_OK) {
   711     return status;
   712   }
   714   // We have a heap so create the methodOop caches before
   715   // CompactingPermGenGen::initialize_oops() tries to populate them.
   716   Universe::_finalizer_register_cache = new LatestMethodOopCache();
   717   Universe::_loader_addClass_cache    = new LatestMethodOopCache();
   718   Universe::_reflect_invoke_cache     = new ActiveMethodOopsCache();
   720   if (UseSharedSpaces) {
   722     // Read the data structures supporting the shared spaces (shared
   723     // system dictionary, symbol table, etc.).  After that, access to
   724     // the file (other than the mapped regions) is no longer needed, and
   725     // the file is closed. Closing the file does not affect the
   726     // currently mapped regions.
   728     CompactingPermGenGen::initialize_oops();
   729     mapinfo->close();
   731   } else {
   732     SymbolTable::create_table();
   733     StringTable::create_table();
   734     ClassLoader::create_package_info_table();
   735   }
   737   return JNI_OK;
   738 }
   740 // Choose the heap base address and oop encoding mode
   741 // when compressed oops are used:
   742 // Unscaled  - Use 32-bits oops without encoding when
   743 //     NarrowOopHeapBaseMin + heap_size < 4Gb
   744 // ZeroBased - Use zero based compressed oops with encoding when
   745 //     NarrowOopHeapBaseMin + heap_size < 32Gb
   746 // HeapBased - Use compressed oops with heap base + encoding.
   748 // 4Gb
   749 static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1);
   750 // 32Gb
   751 static const uint64_t OopEncodingHeapMax = NarrowOopHeapMax << LogMinObjAlignmentInBytes;
   753 char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) {
   754   size_t base = 0;
   755 #ifdef _LP64
   756   if (UseCompressedOops) {
   757     assert(mode == UnscaledNarrowOop  ||
   758            mode == ZeroBasedNarrowOop ||
   759            mode == HeapBasedNarrowOop, "mode is invalid");
   760     const size_t total_size = heap_size + HeapBaseMinAddress;
   761     // Return specified base for the first request.
   762     if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
   763       base = HeapBaseMinAddress;
   764     } else if (total_size <= OopEncodingHeapMax && (mode != HeapBasedNarrowOop)) {
   765       if (total_size <= NarrowOopHeapMax && (mode == UnscaledNarrowOop) &&
   766           (Universe::narrow_oop_shift() == 0)) {
   767         // Use 32-bits oops without encoding and
   768         // place heap's top on the 4Gb boundary
   769         base = (NarrowOopHeapMax - heap_size);
   770       } else {
   771         // Can't reserve with NarrowOopShift == 0
   772         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   773         if (mode == UnscaledNarrowOop ||
   774             mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) {
   775           // Use zero based compressed oops with encoding and
   776           // place heap's top on the 32Gb boundary in case
   777           // total_size > 4Gb or failed to reserve below 4Gb.
   778           base = (OopEncodingHeapMax - heap_size);
   779         }
   780       }
   781     } else {
   782       // Can't reserve below 32Gb.
   783       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   784     }
   785     // Set narrow_oop_base and narrow_oop_use_implicit_null_checks
   786     // used in ReservedHeapSpace() constructors.
   787     // The final values will be set in initialize_heap() below.
   788     if (base != 0 && (base + heap_size) <= OopEncodingHeapMax) {
   789       // Use zero based compressed oops
   790       Universe::set_narrow_oop_base(NULL);
   791       // Don't need guard page for implicit checks in indexed
   792       // addressing mode with zero based Compressed Oops.
   793       Universe::set_narrow_oop_use_implicit_null_checks(true);
   794     } else {
   795       // Set to a non-NULL value so the ReservedSpace ctor computes
   796       // the correct no-access prefix.
   797       // The final value will be set in initialize_heap() below.
   798       Universe::set_narrow_oop_base((address)NarrowOopHeapMax);
   799 #ifdef _WIN64
   800       if (UseLargePages) {
   801         // Cannot allocate guard pages for implicit checks in indexed
   802         // addressing mode when large pages are specified on windows.
   803         Universe::set_narrow_oop_use_implicit_null_checks(false);
   804       }
   805 #endif //  _WIN64
   806     }
   807   }
   808 #endif
   809   return (char*)base; // also return NULL (don't care) for 32-bit VM
   810 }
   812 jint Universe::initialize_heap() {
   814   if (UseParallelGC) {
   815 #ifndef SERIALGC
   816     Universe::_collectedHeap = new ParallelScavengeHeap();
   817 #else  // SERIALGC
   818     fatal("UseParallelGC not supported in java kernel vm.");
   819 #endif // SERIALGC
   821   } else if (UseG1GC) {
   822 #ifndef SERIALGC
   823     G1CollectorPolicy* g1p = new G1CollectorPolicy_BestRegionsFirst();
   824     G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
   825     Universe::_collectedHeap = g1h;
   826 #else  // SERIALGC
   827     fatal("UseG1GC not supported in java kernel vm.");
   828 #endif // SERIALGC
   830   } else {
   831     GenCollectorPolicy *gc_policy;
   833     if (UseSerialGC) {
   834       gc_policy = new MarkSweepPolicy();
   835     } else if (UseConcMarkSweepGC) {
   836 #ifndef SERIALGC
   837       if (UseAdaptiveSizePolicy) {
   838         gc_policy = new ASConcurrentMarkSweepPolicy();
   839       } else {
   840         gc_policy = new ConcurrentMarkSweepPolicy();
   841       }
   842 #else   // SERIALGC
   843     fatal("UseConcMarkSweepGC not supported in java kernel vm.");
   844 #endif // SERIALGC
   845     } else { // default old generation
   846       gc_policy = new MarkSweepPolicy();
   847     }
   849     Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
   850   }
   852   jint status = Universe::heap()->initialize();
   853   if (status != JNI_OK) {
   854     return status;
   855   }
   857 #ifdef _LP64
   858   if (UseCompressedOops) {
   859     // Subtract a page because something can get allocated at heap base.
   860     // This also makes implicit null checking work, because the
   861     // memory+1 page below heap_base needs to cause a signal.
   862     // See needs_explicit_null_check.
   863     // Only set the heap base for compressed oops because it indicates
   864     // compressed oops for pstack code.
   865     if (PrintCompressedOopsMode) {
   866       tty->cr();
   867       tty->print("heap address: "PTR_FORMAT, Universe::heap()->base());
   868     }
   869     if ((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) {
   870       // Can't reserve heap below 32Gb.
   871       Universe::set_narrow_oop_base(Universe::heap()->base() - os::vm_page_size());
   872       Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   873       if (PrintCompressedOopsMode) {
   874         tty->print(", Compressed Oops with base: "PTR_FORMAT, Universe::narrow_oop_base());
   875       }
   876     } else {
   877       Universe::set_narrow_oop_base(0);
   878       if (PrintCompressedOopsMode) {
   879         tty->print(", zero based Compressed Oops");
   880       }
   881 #ifdef _WIN64
   882       if (!Universe::narrow_oop_use_implicit_null_checks()) {
   883         // Don't need guard page for implicit checks in indexed addressing
   884         // mode with zero based Compressed Oops.
   885         Universe::set_narrow_oop_use_implicit_null_checks(true);
   886       }
   887 #endif //  _WIN64
   888       if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) {
   889         // Can't reserve heap below 4Gb.
   890         Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
   891       } else {
   892         Universe::set_narrow_oop_shift(0);
   893         if (PrintCompressedOopsMode) {
   894           tty->print(", 32-bits Oops");
   895         }
   896       }
   897     }
   898     if (PrintCompressedOopsMode) {
   899       tty->cr();
   900       tty->cr();
   901     }
   902   }
   903   assert(Universe::narrow_oop_base() == (Universe::heap()->base() - os::vm_page_size()) ||
   904          Universe::narrow_oop_base() == NULL, "invalid value");
   905   assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
   906          Universe::narrow_oop_shift() == 0, "invalid value");
   907 #endif
   909   // We will never reach the CATCH below since Exceptions::_throw will cause
   910   // the VM to exit if an exception is thrown during initialization
   912   if (UseTLAB) {
   913     assert(Universe::heap()->supports_tlab_allocation(),
   914            "Should support thread-local allocation buffers");
   915     ThreadLocalAllocBuffer::startup_initialization();
   916   }
   917   return JNI_OK;
   918 }
   920 // It's the caller's repsonsibility to ensure glitch-freedom
   921 // (if required).
   922 void Universe::update_heap_info_at_gc() {
   923   _heap_capacity_at_last_gc = heap()->capacity();
   924   _heap_used_at_last_gc     = heap()->used();
   925 }
   929 void universe2_init() {
   930   EXCEPTION_MARK;
   931   Universe::genesis(CATCH);
   932   // Although we'd like to verify here that the state of the heap
   933   // is good, we can't because the main thread has not yet added
   934   // itself to the threads list (so, using current interfaces
   935   // we can't "fill" its TLAB), unless TLABs are disabled.
   936   if (VerifyBeforeGC && !UseTLAB &&
   937       Universe::heap()->total_collections() >= VerifyGCStartAt) {
   938      Universe::heap()->prepare_for_verify();
   939      Universe::verify();   // make sure we're starting with a clean slate
   940   }
   941 }
   944 // This function is defined in JVM.cpp
   945 extern void initialize_converter_functions();
   947 bool universe_post_init() {
   948   Universe::_fully_initialized = true;
   949   EXCEPTION_MARK;
   950   { ResourceMark rm;
   951     Interpreter::initialize();      // needed for interpreter entry points
   952     if (!UseSharedSpaces) {
   953       KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
   954       Universe::reinitialize_vtable_of(ok_h, CHECK_false);
   955       Universe::reinitialize_itables(CHECK_false);
   956     }
   957   }
   959   klassOop k;
   960   instanceKlassHandle k_h;
   961   if (!UseSharedSpaces) {
   962     // Setup preallocated empty java.lang.Class array
   963     Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
   964     // Setup preallocated OutOfMemoryError errors
   965     k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_OutOfMemoryError(), true, CHECK_false);
   966     k_h = instanceKlassHandle(THREAD, k);
   967     Universe::_out_of_memory_error_java_heap = k_h->allocate_permanent_instance(CHECK_false);
   968     Universe::_out_of_memory_error_perm_gen = k_h->allocate_permanent_instance(CHECK_false);
   969     Universe::_out_of_memory_error_array_size = k_h->allocate_permanent_instance(CHECK_false);
   970     Universe::_out_of_memory_error_gc_overhead_limit =
   971       k_h->allocate_permanent_instance(CHECK_false);
   973     // Setup preallocated NullPointerException
   974     // (this is currently used for a cheap & dirty solution in compiler exception handling)
   975     k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_NullPointerException(), true, CHECK_false);
   976     Universe::_null_ptr_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
   977     // Setup preallocated ArithmeticException
   978     // (this is currently used for a cheap & dirty solution in compiler exception handling)
   979     k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_ArithmeticException(), true, CHECK_false);
   980     Universe::_arithmetic_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
   981     // Virtual Machine Error for when we get into a situation we can't resolve
   982     k = SystemDictionary::resolve_or_fail(
   983       vmSymbolHandles::java_lang_VirtualMachineError(), true, CHECK_false);
   984     bool linked = instanceKlass::cast(k)->link_class_or_fail(CHECK_false);
   985     if (!linked) {
   986       tty->print_cr("Unable to link/verify VirtualMachineError class");
   987       return false; // initialization failed
   988     }
   989     Universe::_virtual_machine_error_instance =
   990       instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false);
   991   }
   992   if (!DumpSharedSpaces) {
   993     // These are the only Java fields that are currently set during shared space dumping.
   994     // We prefer to not handle this generally, so we always reinitialize these detail messages.
   995     Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
   996     java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
   998     msg = java_lang_String::create_from_str("PermGen space", CHECK_false);
   999     java_lang_Throwable::set_message(Universe::_out_of_memory_error_perm_gen, msg());
  1001     msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
  1002     java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
  1004     msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
  1005     java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
  1007     msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
  1008     java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
  1010     // Setup the array of errors that have preallocated backtrace
  1011     k = Universe::_out_of_memory_error_java_heap->klass();
  1012     assert(k->klass_part()->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
  1013     k_h = instanceKlassHandle(THREAD, k);
  1015     int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
  1016     Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
  1017     for (int i=0; i<len; i++) {
  1018       oop err = k_h->allocate_permanent_instance(CHECK_false);
  1019       Handle err_h = Handle(THREAD, err);
  1020       java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
  1021       Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
  1023     Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
  1027   // Setup static method for registering finalizers
  1028   // The finalizer klass must be linked before looking up the method, in
  1029   // case it needs to get rewritten.
  1030   instanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
  1031   methodOop m = instanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
  1032                                   vmSymbols::register_method_name(),
  1033                                   vmSymbols::register_method_signature());
  1034   if (m == NULL || !m->is_static()) {
  1035     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
  1036       "java.lang.ref.Finalizer.register", false);
  1038   Universe::_finalizer_register_cache->init(
  1039     SystemDictionary::Finalizer_klass(), m, CHECK_false);
  1041   // Resolve on first use and initialize class.
  1042   // Note: No race-condition here, since a resolve will always return the same result
  1044   // Setup method for security checks
  1045   k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_reflect_Method(), true, CHECK_false);
  1046   k_h = instanceKlassHandle(THREAD, k);
  1047   k_h->link_class(CHECK_false);
  1048   m = k_h->find_method(vmSymbols::invoke_name(), vmSymbols::object_array_object_object_signature());
  1049   if (m == NULL || m->is_static()) {
  1050     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
  1051       "java.lang.reflect.Method.invoke", false);
  1053   Universe::_reflect_invoke_cache->init(k_h(), m, CHECK_false);
  1055   // Setup method for registering loaded classes in class loader vector
  1056   instanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
  1057   m = instanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
  1058   if (m == NULL || m->is_static()) {
  1059     THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(),
  1060       "java.lang.ClassLoader.addClass", false);
  1062   Universe::_loader_addClass_cache->init(
  1063     SystemDictionary::ClassLoader_klass(), m, CHECK_false);
  1065   // The folowing is initializing converter functions for serialization in
  1066   // JVM.cpp. If we clean up the StrictMath code above we may want to find
  1067   // a better solution for this as well.
  1068   initialize_converter_functions();
  1070   // This needs to be done before the first scavenge/gc, since
  1071   // it's an input to soft ref clearing policy.
  1073     MutexLocker x(Heap_lock);
  1074     Universe::update_heap_info_at_gc();
  1077   // ("weak") refs processing infrastructure initialization
  1078   Universe::heap()->post_initialize();
  1080   GC_locker::unlock();  // allow gc after bootstrapping
  1082   MemoryService::set_universe_heap(Universe::_collectedHeap);
  1083   return true;
  1087 void Universe::compute_base_vtable_size() {
  1088   _base_vtable_size = ClassLoader::compute_Object_vtable();
  1092 // %%% The Universe::flush_foo methods belong in CodeCache.
  1094 // Flushes compiled methods dependent on dependee.
  1095 void Universe::flush_dependents_on(instanceKlassHandle dependee) {
  1096   assert_lock_strong(Compile_lock);
  1098   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
  1100   // CodeCache can only be updated by a thread_in_VM and they will all be
  1101   // stopped dring the safepoint so CodeCache will be safe to update without
  1102   // holding the CodeCache_lock.
  1104   DepChange changes(dependee);
  1106   // Compute the dependent nmethods
  1107   if (CodeCache::mark_for_deoptimization(changes) > 0) {
  1108     // At least one nmethod has been marked for deoptimization
  1109     VM_Deoptimize op;
  1110     VMThread::execute(&op);
  1114 #ifdef HOTSWAP
  1115 // Flushes compiled methods dependent on dependee in the evolutionary sense
  1116 void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
  1117   // --- Compile_lock is not held. However we are at a safepoint.
  1118   assert_locked_or_safepoint(Compile_lock);
  1119   if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
  1121   // CodeCache can only be updated by a thread_in_VM and they will all be
  1122   // stopped dring the safepoint so CodeCache will be safe to update without
  1123   // holding the CodeCache_lock.
  1125   // Compute the dependent nmethods
  1126   if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
  1127     // At least one nmethod has been marked for deoptimization
  1129     // All this already happens inside a VM_Operation, so we'll do all the work here.
  1130     // Stuff copied from VM_Deoptimize and modified slightly.
  1132     // We do not want any GCs to happen while we are in the middle of this VM operation
  1133     ResourceMark rm;
  1134     DeoptimizationMarker dm;
  1136     // Deoptimize all activations depending on marked nmethods
  1137     Deoptimization::deoptimize_dependents();
  1139     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
  1140     CodeCache::make_marked_nmethods_not_entrant();
  1143 #endif // HOTSWAP
  1146 // Flushes compiled methods dependent on dependee
  1147 void Universe::flush_dependents_on_method(methodHandle m_h) {
  1148   // --- Compile_lock is not held. However we are at a safepoint.
  1149   assert_locked_or_safepoint(Compile_lock);
  1151   // CodeCache can only be updated by a thread_in_VM and they will all be
  1152   // stopped dring the safepoint so CodeCache will be safe to update without
  1153   // holding the CodeCache_lock.
  1155   // Compute the dependent nmethods
  1156   if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
  1157     // At least one nmethod has been marked for deoptimization
  1159     // All this already happens inside a VM_Operation, so we'll do all the work here.
  1160     // Stuff copied from VM_Deoptimize and modified slightly.
  1162     // We do not want any GCs to happen while we are in the middle of this VM operation
  1163     ResourceMark rm;
  1164     DeoptimizationMarker dm;
  1166     // Deoptimize all activations depending on marked nmethods
  1167     Deoptimization::deoptimize_dependents();
  1169     // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
  1170     CodeCache::make_marked_nmethods_not_entrant();
  1174 void Universe::print() { print_on(gclog_or_tty); }
  1176 void Universe::print_on(outputStream* st) {
  1177   st->print_cr("Heap");
  1178   heap()->print_on(st);
  1181 void Universe::print_heap_at_SIGBREAK() {
  1182   if (PrintHeapAtSIGBREAK) {
  1183     MutexLocker hl(Heap_lock);
  1184     print_on(tty);
  1185     tty->cr();
  1186     tty->flush();
  1190 void Universe::print_heap_before_gc(outputStream* st) {
  1191   st->print_cr("{Heap before GC invocations=%u (full %u):",
  1192                heap()->total_collections(),
  1193                heap()->total_full_collections());
  1194   heap()->print_on(st);
  1197 void Universe::print_heap_after_gc(outputStream* st) {
  1198   st->print_cr("Heap after GC invocations=%u (full %u):",
  1199                heap()->total_collections(),
  1200                heap()->total_full_collections());
  1201   heap()->print_on(st);
  1202   st->print_cr("}");
  1205 void Universe::verify(bool allow_dirty, bool silent, bool option) {
  1206   if (SharedSkipVerify) {
  1207     return;
  1210   // The use of _verify_in_progress is a temporary work around for
  1211   // 6320749.  Don't bother with a creating a class to set and clear
  1212   // it since it is only used in this method and the control flow is
  1213   // straight forward.
  1214   _verify_in_progress = true;
  1216   COMPILER2_PRESENT(
  1217     assert(!DerivedPointerTable::is_active(),
  1218          "DPT should not be active during verification "
  1219          "(of thread stacks below)");
  1222   ResourceMark rm;
  1223   HandleMark hm;  // Handles created during verification can be zapped
  1224   _verify_count++;
  1226   if (!silent) gclog_or_tty->print("[Verifying ");
  1227   if (!silent) gclog_or_tty->print("threads ");
  1228   Threads::verify();
  1229   heap()->verify(allow_dirty, silent, option);
  1231   if (!silent) gclog_or_tty->print("syms ");
  1232   SymbolTable::verify();
  1233   if (!silent) gclog_or_tty->print("strs ");
  1234   StringTable::verify();
  1236     MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
  1237     if (!silent) gclog_or_tty->print("zone ");
  1238     CodeCache::verify();
  1240   if (!silent) gclog_or_tty->print("dict ");
  1241   SystemDictionary::verify();
  1242   if (!silent) gclog_or_tty->print("hand ");
  1243   JNIHandles::verify();
  1244   if (!silent) gclog_or_tty->print("C-heap ");
  1245   os::check_heap();
  1246   if (!silent) gclog_or_tty->print_cr("]");
  1248   _verify_in_progress = false;
  1251 // Oop verification (see MacroAssembler::verify_oop)
  1253 static uintptr_t _verify_oop_data[2]   = {0, (uintptr_t)-1};
  1254 static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};
  1257 static void calculate_verify_data(uintptr_t verify_data[2],
  1258                                   HeapWord* low_boundary,
  1259                                   HeapWord* high_boundary) {
  1260   assert(low_boundary < high_boundary, "bad interval");
  1262   // decide which low-order bits we require to be clear:
  1263   size_t alignSize = MinObjAlignmentInBytes;
  1264   size_t min_object_size = oopDesc::header_size();
  1266   // make an inclusive limit:
  1267   uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
  1268   uintptr_t min = (uintptr_t)low_boundary;
  1269   assert(min < max, "bad interval");
  1270   uintptr_t diff = max ^ min;
  1272   // throw away enough low-order bits to make the diff vanish
  1273   uintptr_t mask = (uintptr_t)(-1);
  1274   while ((mask & diff) != 0)
  1275     mask <<= 1;
  1276   uintptr_t bits = (min & mask);
  1277   assert(bits == (max & mask), "correct mask");
  1278   // check an intermediate value between min and max, just to make sure:
  1279   assert(bits == ((min + (max-min)/2) & mask), "correct mask");
  1281   // require address alignment, too:
  1282   mask |= (alignSize - 1);
  1284   if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
  1285     assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
  1287   verify_data[0] = mask;
  1288   verify_data[1] = bits;
  1292 // Oop verification (see MacroAssembler::verify_oop)
  1293 #ifndef PRODUCT
  1295 uintptr_t Universe::verify_oop_mask() {
  1296   MemRegion m = heap()->reserved_region();
  1297   calculate_verify_data(_verify_oop_data,
  1298                         m.start(),
  1299                         m.end());
  1300   return _verify_oop_data[0];
  1305 uintptr_t Universe::verify_oop_bits() {
  1306   verify_oop_mask();
  1307   return _verify_oop_data[1];
  1311 uintptr_t Universe::verify_klass_mask() {
  1312   /* $$$
  1313   // A klass can never live in the new space.  Since the new and old
  1314   // spaces can change size, we must settle for bounds-checking against
  1315   // the bottom of the world, plus the smallest possible new and old
  1316   // space sizes that may arise during execution.
  1317   size_t min_new_size = Universe::new_size();   // in bytes
  1318   size_t min_old_size = Universe::old_size();   // in bytes
  1319   calculate_verify_data(_verify_klass_data,
  1320           (HeapWord*)((uintptr_t)_new_gen->low_boundary + min_new_size + min_old_size),
  1321           _perm_gen->high_boundary);
  1322                         */
  1323   // Why doesn't the above just say that klass's always live in the perm
  1324   // gen?  I'll see if that seems to work...
  1325   MemRegion permanent_reserved;
  1326   switch (Universe::heap()->kind()) {
  1327   default:
  1328     // ???: What if a CollectedHeap doesn't have a permanent generation?
  1329     ShouldNotReachHere();
  1330     break;
  1331   case CollectedHeap::GenCollectedHeap:
  1332   case CollectedHeap::G1CollectedHeap: {
  1333     SharedHeap* sh = (SharedHeap*) Universe::heap();
  1334     permanent_reserved = sh->perm_gen()->reserved();
  1335    break;
  1337 #ifndef SERIALGC
  1338   case CollectedHeap::ParallelScavengeHeap: {
  1339     ParallelScavengeHeap* psh = (ParallelScavengeHeap*) Universe::heap();
  1340     permanent_reserved = psh->perm_gen()->reserved();
  1341     break;
  1343 #endif // SERIALGC
  1345   calculate_verify_data(_verify_klass_data,
  1346                         permanent_reserved.start(),
  1347                         permanent_reserved.end());
  1349   return _verify_klass_data[0];
  1354 uintptr_t Universe::verify_klass_bits() {
  1355   verify_klass_mask();
  1356   return _verify_klass_data[1];
  1360 uintptr_t Universe::verify_mark_mask() {
  1361   return markOopDesc::lock_mask_in_place;
  1366 uintptr_t Universe::verify_mark_bits() {
  1367   intptr_t mask = verify_mark_mask();
  1368   intptr_t bits = (intptr_t)markOopDesc::prototype();
  1369   assert((bits & ~mask) == 0, "no stray header bits");
  1370   return bits;
  1372 #endif // PRODUCT
  1375 void Universe::compute_verify_oop_data() {
  1376   verify_oop_mask();
  1377   verify_oop_bits();
  1378   verify_mark_mask();
  1379   verify_mark_bits();
  1380   verify_klass_mask();
  1381   verify_klass_bits();
  1385 void CommonMethodOopCache::init(klassOop k, methodOop m, TRAPS) {
  1386   if (!UseSharedSpaces) {
  1387     _klass = k;
  1389 #ifndef PRODUCT
  1390   else {
  1391     // sharing initilization should have already set up _klass
  1392     assert(_klass != NULL, "just checking");
  1394 #endif
  1396   _method_idnum = m->method_idnum();
  1397   assert(_method_idnum >= 0, "sanity check");
  1401 ActiveMethodOopsCache::~ActiveMethodOopsCache() {
  1402   if (_prev_methods != NULL) {
  1403     for (int i = _prev_methods->length() - 1; i >= 0; i--) {
  1404       jweak method_ref = _prev_methods->at(i);
  1405       if (method_ref != NULL) {
  1406         JNIHandles::destroy_weak_global(method_ref);
  1409     delete _prev_methods;
  1410     _prev_methods = NULL;
  1415 void ActiveMethodOopsCache::add_previous_version(const methodOop method) {
  1416   assert(Thread::current()->is_VM_thread(),
  1417     "only VMThread can add previous versions");
  1419   if (_prev_methods == NULL) {
  1420     // This is the first previous version so make some space.
  1421     // Start with 2 elements under the assumption that the class
  1422     // won't be redefined much.
  1423     _prev_methods = new (ResourceObj::C_HEAP) GrowableArray<jweak>(2, true);
  1426   // RC_TRACE macro has an embedded ResourceMark
  1427   RC_TRACE(0x00000100,
  1428     ("add: %s(%s): adding prev version ref for cached method @%d",
  1429     method->name()->as_C_string(), method->signature()->as_C_string(),
  1430     _prev_methods->length()));
  1432   methodHandle method_h(method);
  1433   jweak method_ref = JNIHandles::make_weak_global(method_h);
  1434   _prev_methods->append(method_ref);
  1436   // Using weak references allows previous versions of the cached
  1437   // method to be GC'ed when they are no longer needed. Since the
  1438   // caller is the VMThread and we are at a safepoint, this is a good
  1439   // time to clear out unused weak references.
  1441   for (int i = _prev_methods->length() - 1; i >= 0; i--) {
  1442     jweak method_ref = _prev_methods->at(i);
  1443     assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
  1444     if (method_ref == NULL) {
  1445       _prev_methods->remove_at(i);
  1446       // Since we are traversing the array backwards, we don't have to
  1447       // do anything special with the index.
  1448       continue;  // robustness
  1451     methodOop m = (methodOop)JNIHandles::resolve(method_ref);
  1452     if (m == NULL) {
  1453       // this method entry has been GC'ed so remove it
  1454       JNIHandles::destroy_weak_global(method_ref);
  1455       _prev_methods->remove_at(i);
  1456     } else {
  1457       // RC_TRACE macro has an embedded ResourceMark
  1458       RC_TRACE(0x00000400, ("add: %s(%s): previous cached method @%d is alive",
  1459         m->name()->as_C_string(), m->signature()->as_C_string(), i));
  1462 } // end add_previous_version()
  1465 bool ActiveMethodOopsCache::is_same_method(const methodOop method) const {
  1466   instanceKlass* ik = instanceKlass::cast(klass());
  1467   methodOop check_method = ik->method_with_idnum(method_idnum());
  1468   assert(check_method != NULL, "sanity check");
  1469   if (check_method == method) {
  1470     // done with the easy case
  1471     return true;
  1474   if (_prev_methods != NULL) {
  1475     // The cached method has been redefined at least once so search
  1476     // the previous versions for a match.
  1477     for (int i = 0; i < _prev_methods->length(); i++) {
  1478       jweak method_ref = _prev_methods->at(i);
  1479       assert(method_ref != NULL, "weak method ref was unexpectedly cleared");
  1480       if (method_ref == NULL) {
  1481         continue;  // robustness
  1484       check_method = (methodOop)JNIHandles::resolve(method_ref);
  1485       if (check_method == method) {
  1486         // a previous version matches
  1487         return true;
  1492   // either no previous versions or no previous version matched
  1493   return false;
  1497 methodOop LatestMethodOopCache::get_methodOop() {
  1498   instanceKlass* ik = instanceKlass::cast(klass());
  1499   methodOop m = ik->method_with_idnum(method_idnum());
  1500   assert(m != NULL, "sanity check");
  1501   return m;
  1505 #ifdef ASSERT
  1506 // Release dummy object(s) at bottom of heap
  1507 bool Universe::release_fullgc_alot_dummy() {
  1508   MutexLocker ml(FullGCALot_lock);
  1509   if (_fullgc_alot_dummy_array != NULL) {
  1510     if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
  1511       // No more dummies to release, release entire array instead
  1512       _fullgc_alot_dummy_array = NULL;
  1513       return false;
  1515     if (!UseConcMarkSweepGC) {
  1516       // Release dummy at bottom of old generation
  1517       _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
  1519     // Release dummy at bottom of permanent generation
  1520     _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
  1522   return true;
  1525 #endif // ASSERT

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