/* * Copyright 1997-2009 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. * */ # include "incls/_precompiled.incl" # include "incls/_universe.cpp.incl" // Known objects klassOop Universe::_boolArrayKlassObj = NULL; klassOop Universe::_byteArrayKlassObj = NULL; klassOop Universe::_charArrayKlassObj = NULL; klassOop Universe::_intArrayKlassObj = NULL; klassOop Universe::_shortArrayKlassObj = NULL; klassOop Universe::_longArrayKlassObj = NULL; klassOop Universe::_singleArrayKlassObj = NULL; klassOop Universe::_doubleArrayKlassObj = NULL; klassOop Universe::_typeArrayKlassObjs[T_VOID+1] = { NULL /*, NULL...*/ }; klassOop Universe::_objectArrayKlassObj = NULL; klassOop Universe::_symbolKlassObj = NULL; klassOop Universe::_methodKlassObj = NULL; klassOop Universe::_constMethodKlassObj = NULL; klassOop Universe::_methodDataKlassObj = NULL; klassOop Universe::_klassKlassObj = NULL; klassOop Universe::_arrayKlassKlassObj = NULL; klassOop Universe::_objArrayKlassKlassObj = NULL; klassOop Universe::_typeArrayKlassKlassObj = NULL; klassOop Universe::_instanceKlassKlassObj = NULL; klassOop Universe::_constantPoolKlassObj = NULL; klassOop Universe::_constantPoolCacheKlassObj = NULL; klassOop Universe::_compiledICHolderKlassObj = NULL; klassOop Universe::_systemObjArrayKlassObj = NULL; oop Universe::_int_mirror = NULL; oop Universe::_float_mirror = NULL; oop Universe::_double_mirror = NULL; oop Universe::_byte_mirror = NULL; oop Universe::_bool_mirror = NULL; oop Universe::_char_mirror = NULL; oop Universe::_long_mirror = NULL; oop Universe::_short_mirror = NULL; oop Universe::_void_mirror = NULL; oop Universe::_mirrors[T_VOID+1] = { NULL /*, NULL...*/ }; oop Universe::_main_thread_group = NULL; oop Universe::_system_thread_group = NULL; typeArrayOop Universe::_the_empty_byte_array = NULL; typeArrayOop Universe::_the_empty_short_array = NULL; typeArrayOop Universe::_the_empty_int_array = NULL; objArrayOop Universe::_the_empty_system_obj_array = NULL; objArrayOop Universe::_the_empty_class_klass_array = NULL; objArrayOop Universe::_the_array_interfaces_array = NULL; LatestMethodOopCache* Universe::_finalizer_register_cache = NULL; LatestMethodOopCache* Universe::_loader_addClass_cache = NULL; ActiveMethodOopsCache* Universe::_reflect_invoke_cache = NULL; oop Universe::_out_of_memory_error_java_heap = NULL; oop Universe::_out_of_memory_error_perm_gen = NULL; oop Universe::_out_of_memory_error_array_size = NULL; oop Universe::_out_of_memory_error_gc_overhead_limit = NULL; objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL; volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0; bool Universe::_verify_in_progress = false; oop Universe::_null_ptr_exception_instance = NULL; oop Universe::_arithmetic_exception_instance = NULL; oop Universe::_virtual_machine_error_instance = NULL; oop Universe::_vm_exception = NULL; oop Universe::_emptySymbol = NULL; // These variables are guarded by FullGCALot_lock. debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;) debug_only(int Universe::_fullgc_alot_dummy_next = 0;) // Heap int Universe::_verify_count = 0; int Universe::_base_vtable_size = 0; bool Universe::_bootstrapping = false; bool Universe::_fully_initialized = false; size_t Universe::_heap_capacity_at_last_gc; size_t Universe::_heap_used_at_last_gc = 0; CollectedHeap* Universe::_collectedHeap = NULL; NarrowOopStruct Universe::_narrow_oop = { NULL, 0, true }; void Universe::basic_type_classes_do(void f(klassOop)) { f(boolArrayKlassObj()); f(byteArrayKlassObj()); f(charArrayKlassObj()); f(intArrayKlassObj()); f(shortArrayKlassObj()); f(longArrayKlassObj()); f(singleArrayKlassObj()); f(doubleArrayKlassObj()); } void Universe::system_classes_do(void f(klassOop)) { f(symbolKlassObj()); f(methodKlassObj()); f(constMethodKlassObj()); f(methodDataKlassObj()); f(klassKlassObj()); f(arrayKlassKlassObj()); f(objArrayKlassKlassObj()); f(typeArrayKlassKlassObj()); f(instanceKlassKlassObj()); f(constantPoolKlassObj()); f(systemObjArrayKlassObj()); } void Universe::oops_do(OopClosure* f, bool do_all) { f->do_oop((oop*) &_int_mirror); f->do_oop((oop*) &_float_mirror); f->do_oop((oop*) &_double_mirror); f->do_oop((oop*) &_byte_mirror); f->do_oop((oop*) &_bool_mirror); f->do_oop((oop*) &_char_mirror); f->do_oop((oop*) &_long_mirror); f->do_oop((oop*) &_short_mirror); f->do_oop((oop*) &_void_mirror); // It's important to iterate over these guys even if they are null, // since that's how shared heaps are restored. for (int i = T_BOOLEAN; i < T_VOID+1; i++) { f->do_oop((oop*) &_mirrors[i]); } assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking"); // %%% Consider moving those "shared oops" over here with the others. f->do_oop((oop*)&_boolArrayKlassObj); f->do_oop((oop*)&_byteArrayKlassObj); f->do_oop((oop*)&_charArrayKlassObj); f->do_oop((oop*)&_intArrayKlassObj); f->do_oop((oop*)&_shortArrayKlassObj); f->do_oop((oop*)&_longArrayKlassObj); f->do_oop((oop*)&_singleArrayKlassObj); f->do_oop((oop*)&_doubleArrayKlassObj); f->do_oop((oop*)&_objectArrayKlassObj); { for (int i = 0; i < T_VOID+1; i++) { if (_typeArrayKlassObjs[i] != NULL) { assert(i >= T_BOOLEAN, "checking"); f->do_oop((oop*)&_typeArrayKlassObjs[i]); } else if (do_all) { f->do_oop((oop*)&_typeArrayKlassObjs[i]); } } } f->do_oop((oop*)&_symbolKlassObj); f->do_oop((oop*)&_methodKlassObj); f->do_oop((oop*)&_constMethodKlassObj); f->do_oop((oop*)&_methodDataKlassObj); f->do_oop((oop*)&_klassKlassObj); f->do_oop((oop*)&_arrayKlassKlassObj); f->do_oop((oop*)&_objArrayKlassKlassObj); f->do_oop((oop*)&_typeArrayKlassKlassObj); f->do_oop((oop*)&_instanceKlassKlassObj); f->do_oop((oop*)&_constantPoolKlassObj); f->do_oop((oop*)&_constantPoolCacheKlassObj); f->do_oop((oop*)&_compiledICHolderKlassObj); f->do_oop((oop*)&_systemObjArrayKlassObj); f->do_oop((oop*)&_the_empty_byte_array); f->do_oop((oop*)&_the_empty_short_array); f->do_oop((oop*)&_the_empty_int_array); f->do_oop((oop*)&_the_empty_system_obj_array); f->do_oop((oop*)&_the_empty_class_klass_array); f->do_oop((oop*)&_the_array_interfaces_array); _finalizer_register_cache->oops_do(f); _loader_addClass_cache->oops_do(f); _reflect_invoke_cache->oops_do(f); f->do_oop((oop*)&_out_of_memory_error_java_heap); f->do_oop((oop*)&_out_of_memory_error_perm_gen); f->do_oop((oop*)&_out_of_memory_error_array_size); f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit); if (_preallocated_out_of_memory_error_array != (oop)NULL) { // NULL when DumpSharedSpaces f->do_oop((oop*)&_preallocated_out_of_memory_error_array); } f->do_oop((oop*)&_null_ptr_exception_instance); f->do_oop((oop*)&_arithmetic_exception_instance); f->do_oop((oop*)&_virtual_machine_error_instance); f->do_oop((oop*)&_main_thread_group); f->do_oop((oop*)&_system_thread_group); f->do_oop((oop*)&_vm_exception); f->do_oop((oop*)&_emptySymbol); debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);) } void Universe::check_alignment(uintx size, uintx alignment, const char* name) { if (size < alignment || size % alignment != 0) { ResourceMark rm; stringStream st; st.print("Size of %s (%ld bytes) must be aligned to %ld bytes", name, size, alignment); char* error = st.as_string(); vm_exit_during_initialization(error); } } void Universe::genesis(TRAPS) { ResourceMark rm; { FlagSetting fs(_bootstrapping, true); { MutexLocker mc(Compile_lock); // determine base vtable size; without that we cannot create the array klasses compute_base_vtable_size(); if (!UseSharedSpaces) { _klassKlassObj = klassKlass::create_klass(CHECK); _arrayKlassKlassObj = arrayKlassKlass::create_klass(CHECK); _objArrayKlassKlassObj = objArrayKlassKlass::create_klass(CHECK); _instanceKlassKlassObj = instanceKlassKlass::create_klass(CHECK); _typeArrayKlassKlassObj = typeArrayKlassKlass::create_klass(CHECK); _symbolKlassObj = symbolKlass::create_klass(CHECK); _emptySymbol = oopFactory::new_symbol("", CHECK); _boolArrayKlassObj = typeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK); _charArrayKlassObj = typeArrayKlass::create_klass(T_CHAR, sizeof(jchar), CHECK); _singleArrayKlassObj = typeArrayKlass::create_klass(T_FLOAT, sizeof(jfloat), CHECK); _doubleArrayKlassObj = typeArrayKlass::create_klass(T_DOUBLE, sizeof(jdouble), CHECK); _byteArrayKlassObj = typeArrayKlass::create_klass(T_BYTE, sizeof(jbyte), CHECK); _shortArrayKlassObj = typeArrayKlass::create_klass(T_SHORT, sizeof(jshort), CHECK); _intArrayKlassObj = typeArrayKlass::create_klass(T_INT, sizeof(jint), CHECK); _longArrayKlassObj = typeArrayKlass::create_klass(T_LONG, sizeof(jlong), CHECK); _typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj; _typeArrayKlassObjs[T_CHAR] = _charArrayKlassObj; _typeArrayKlassObjs[T_FLOAT] = _singleArrayKlassObj; _typeArrayKlassObjs[T_DOUBLE] = _doubleArrayKlassObj; _typeArrayKlassObjs[T_BYTE] = _byteArrayKlassObj; _typeArrayKlassObjs[T_SHORT] = _shortArrayKlassObj; _typeArrayKlassObjs[T_INT] = _intArrayKlassObj; _typeArrayKlassObjs[T_LONG] = _longArrayKlassObj; _methodKlassObj = methodKlass::create_klass(CHECK); _constMethodKlassObj = constMethodKlass::create_klass(CHECK); _methodDataKlassObj = methodDataKlass::create_klass(CHECK); _constantPoolKlassObj = constantPoolKlass::create_klass(CHECK); _constantPoolCacheKlassObj = constantPoolCacheKlass::create_klass(CHECK); _compiledICHolderKlassObj = compiledICHolderKlass::create_klass(CHECK); _systemObjArrayKlassObj = objArrayKlassKlass::cast(objArrayKlassKlassObj())->allocate_system_objArray_klass(CHECK); _the_empty_byte_array = oopFactory::new_permanent_byteArray(0, CHECK); _the_empty_short_array = oopFactory::new_permanent_shortArray(0, CHECK); _the_empty_int_array = oopFactory::new_permanent_intArray(0, CHECK); _the_empty_system_obj_array = oopFactory::new_system_objArray(0, CHECK); _the_array_interfaces_array = oopFactory::new_system_objArray(2, CHECK); _vm_exception = oopFactory::new_symbol("vm exception holder", CHECK); } else { FileMapInfo *mapinfo = FileMapInfo::current_info(); char* buffer = mapinfo->region_base(CompactingPermGenGen::md); void** vtbl_list = (void**)buffer; init_self_patching_vtbl_list(vtbl_list, CompactingPermGenGen::vtbl_list_size); } } vmSymbols::initialize(CHECK); SystemDictionary::initialize(CHECK); klassOop ok = SystemDictionary::object_klass(); if (UseSharedSpaces) { // Verify shared interfaces array. assert(_the_array_interfaces_array->obj_at(0) == SystemDictionary::cloneable_klass(), "u3"); assert(_the_array_interfaces_array->obj_at(1) == SystemDictionary::serializable_klass(), "u3"); // Verify element klass for system obj array klass assert(objArrayKlass::cast(_systemObjArrayKlassObj)->element_klass() == ok, "u1"); assert(objArrayKlass::cast(_systemObjArrayKlassObj)->bottom_klass() == ok, "u2"); // Verify super class for the classes created above assert(Klass::cast(boolArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(charArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(singleArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(doubleArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(byteArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(shortArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(intArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(longArrayKlassObj() )->super() == ok, "u3"); assert(Klass::cast(constantPoolKlassObj() )->super() == ok, "u3"); assert(Klass::cast(systemObjArrayKlassObj())->super() == ok, "u3"); } else { // Set up shared interfaces array. (Do this before supers are set up.) _the_array_interfaces_array->obj_at_put(0, SystemDictionary::cloneable_klass()); _the_array_interfaces_array->obj_at_put(1, SystemDictionary::serializable_klass()); // Set element klass for system obj array klass objArrayKlass::cast(_systemObjArrayKlassObj)->set_element_klass(ok); objArrayKlass::cast(_systemObjArrayKlassObj)->set_bottom_klass(ok); // Set super class for the classes created above Klass::cast(boolArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(charArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(singleArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(doubleArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(byteArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(shortArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(intArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(longArrayKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(constantPoolKlassObj() )->initialize_supers(ok, CHECK); Klass::cast(systemObjArrayKlassObj())->initialize_supers(ok, CHECK); Klass::cast(boolArrayKlassObj() )->set_super(ok); Klass::cast(charArrayKlassObj() )->set_super(ok); Klass::cast(singleArrayKlassObj() )->set_super(ok); Klass::cast(doubleArrayKlassObj() )->set_super(ok); Klass::cast(byteArrayKlassObj() )->set_super(ok); Klass::cast(shortArrayKlassObj() )->set_super(ok); Klass::cast(intArrayKlassObj() )->set_super(ok); Klass::cast(longArrayKlassObj() )->set_super(ok); Klass::cast(constantPoolKlassObj() )->set_super(ok); Klass::cast(systemObjArrayKlassObj())->set_super(ok); } Klass::cast(boolArrayKlassObj() )->append_to_sibling_list(); Klass::cast(charArrayKlassObj() )->append_to_sibling_list(); Klass::cast(singleArrayKlassObj() )->append_to_sibling_list(); Klass::cast(doubleArrayKlassObj() )->append_to_sibling_list(); Klass::cast(byteArrayKlassObj() )->append_to_sibling_list(); Klass::cast(shortArrayKlassObj() )->append_to_sibling_list(); Klass::cast(intArrayKlassObj() )->append_to_sibling_list(); Klass::cast(longArrayKlassObj() )->append_to_sibling_list(); Klass::cast(constantPoolKlassObj() )->append_to_sibling_list(); Klass::cast(systemObjArrayKlassObj())->append_to_sibling_list(); } // end of core bootstrapping // Initialize _objectArrayKlass after core bootstraping to make // sure the super class is set up properly for _objectArrayKlass. _objectArrayKlassObj = instanceKlass:: cast(SystemDictionary::object_klass())->array_klass(1, CHECK); // Add the class to the class hierarchy manually to make sure that // its vtable is initialized after core bootstrapping is completed. Klass::cast(_objectArrayKlassObj)->append_to_sibling_list(); // Compute is_jdk version flags. // Only 1.3 or later has the java.lang.Shutdown class. // Only 1.4 or later has the java.lang.CharSequence interface. // Only 1.5 or later has the java.lang.management.MemoryUsage class. if (JDK_Version::is_partially_initialized()) { uint8_t jdk_version; klassOop k = SystemDictionary::resolve_or_null( vmSymbolHandles::java_lang_management_MemoryUsage(), THREAD); CLEAR_PENDING_EXCEPTION; // ignore exceptions if (k == NULL) { k = SystemDictionary::resolve_or_null( vmSymbolHandles::java_lang_CharSequence(), THREAD); CLEAR_PENDING_EXCEPTION; // ignore exceptions if (k == NULL) { k = SystemDictionary::resolve_or_null( vmSymbolHandles::java_lang_Shutdown(), THREAD); CLEAR_PENDING_EXCEPTION; // ignore exceptions if (k == NULL) { jdk_version = 2; } else { jdk_version = 3; } } else { jdk_version = 4; } } else { jdk_version = 5; } JDK_Version::fully_initialize(jdk_version); } #ifdef ASSERT if (FullGCALot) { // Allocate an array of dummy objects. // We'd like these to be at the bottom of the old generation, // so that when we free one and then collect, // (almost) the whole heap moves // and we find out if we actually update all the oops correctly. // But we can't allocate directly in the old generation, // so we allocate wherever, and hope that the first collection // moves these objects to the bottom of the old generation. // We can allocate directly in the permanent generation, so we do. int size; if (UseConcMarkSweepGC) { warning("Using +FullGCALot with concurrent mark sweep gc " "will not force all objects to relocate"); size = FullGCALotDummies; } else { size = FullGCALotDummies * 2; } objArrayOop naked_array = oopFactory::new_system_objArray(size, CHECK); objArrayHandle dummy_array(THREAD, naked_array); int i = 0; while (i < size) { if (!UseConcMarkSweepGC) { // Allocate dummy in old generation oop dummy = instanceKlass::cast(SystemDictionary::object_klass())->allocate_instance(CHECK); dummy_array->obj_at_put(i++, dummy); } // Allocate dummy in permanent generation oop dummy = instanceKlass::cast(SystemDictionary::object_klass())->allocate_permanent_instance(CHECK); dummy_array->obj_at_put(i++, dummy); } { // Only modify the global variable inside the mutex. // If we had a race to here, the other dummy_array instances // and their elements just get dropped on the floor, which is fine. MutexLocker ml(FullGCALot_lock); if (_fullgc_alot_dummy_array == NULL) { _fullgc_alot_dummy_array = dummy_array(); } } assert(i == _fullgc_alot_dummy_array->length(), "just checking"); } #endif } static inline void add_vtable(void** list, int* n, Klass* o, int count) { list[(*n)++] = *(void**)&o->vtbl_value(); guarantee((*n) <= count, "vtable list too small."); } void Universe::init_self_patching_vtbl_list(void** list, int count) { int n = 0; { klassKlass o; add_vtable(list, &n, &o, count); } { arrayKlassKlass o; add_vtable(list, &n, &o, count); } { objArrayKlassKlass o; add_vtable(list, &n, &o, count); } { instanceKlassKlass o; add_vtable(list, &n, &o, count); } { instanceKlass o; add_vtable(list, &n, &o, count); } { instanceRefKlass o; add_vtable(list, &n, &o, count); } { typeArrayKlassKlass o; add_vtable(list, &n, &o, count); } { symbolKlass o; add_vtable(list, &n, &o, count); } { typeArrayKlass o; add_vtable(list, &n, &o, count); } { methodKlass o; add_vtable(list, &n, &o, count); } { constMethodKlass o; add_vtable(list, &n, &o, count); } { constantPoolKlass o; add_vtable(list, &n, &o, count); } { constantPoolCacheKlass o; add_vtable(list, &n, &o, count); } { objArrayKlass o; add_vtable(list, &n, &o, count); } { methodDataKlass o; add_vtable(list, &n, &o, count); } { compiledICHolderKlass o; add_vtable(list, &n, &o, count); } } class FixupMirrorClosure: public ObjectClosure { public: virtual void do_object(oop obj) { if (obj->is_klass()) { EXCEPTION_MARK; KlassHandle k(THREAD, klassOop(obj)); // We will never reach the CATCH below since Exceptions::_throw will cause // the VM to exit if an exception is thrown during initialization java_lang_Class::create_mirror(k, CATCH); // This call unconditionally creates a new mirror for k, // and links in k's component_mirror field if k is an array. // If k is an objArray, k's element type must already have // a mirror. In other words, this closure must process // the component type of an objArray k before it processes k. // This works because the permgen iterator presents arrays // and their component types in order of creation. } } }; void Universe::initialize_basic_type_mirrors(TRAPS) { if (UseSharedSpaces) { assert(_int_mirror != NULL, "already loaded"); assert(_void_mirror == _mirrors[T_VOID], "consistently loaded"); } else { assert(_int_mirror==NULL, "basic type mirrors already initialized"); _int_mirror = java_lang_Class::create_basic_type_mirror("int", T_INT, CHECK); _float_mirror = java_lang_Class::create_basic_type_mirror("float", T_FLOAT, CHECK); _double_mirror = java_lang_Class::create_basic_type_mirror("double", T_DOUBLE, CHECK); _byte_mirror = java_lang_Class::create_basic_type_mirror("byte", T_BYTE, CHECK); _bool_mirror = java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK); _char_mirror = java_lang_Class::create_basic_type_mirror("char", T_CHAR, CHECK); _long_mirror = java_lang_Class::create_basic_type_mirror("long", T_LONG, CHECK); _short_mirror = java_lang_Class::create_basic_type_mirror("short", T_SHORT, CHECK); _void_mirror = java_lang_Class::create_basic_type_mirror("void", T_VOID, CHECK); _mirrors[T_INT] = _int_mirror; _mirrors[T_FLOAT] = _float_mirror; _mirrors[T_DOUBLE] = _double_mirror; _mirrors[T_BYTE] = _byte_mirror; _mirrors[T_BOOLEAN] = _bool_mirror; _mirrors[T_CHAR] = _char_mirror; _mirrors[T_LONG] = _long_mirror; _mirrors[T_SHORT] = _short_mirror; _mirrors[T_VOID] = _void_mirror; //_mirrors[T_OBJECT] = instanceKlass::cast(_object_klass)->java_mirror(); //_mirrors[T_ARRAY] = instanceKlass::cast(_object_klass)->java_mirror(); } } void Universe::fixup_mirrors(TRAPS) { // Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly, // but we cannot do that for classes created before java.lang.Class is loaded. Here we simply // walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note // that the number of objects allocated at this point is very small. assert(SystemDictionary::class_klass_loaded(), "java.lang.Class should be loaded"); FixupMirrorClosure blk; Universe::heap()->permanent_object_iterate(&blk); } static bool has_run_finalizers_on_exit = false; void Universe::run_finalizers_on_exit() { if (has_run_finalizers_on_exit) return; has_run_finalizers_on_exit = true; // Called on VM exit. This ought to be run in a separate thread. if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit"); { PRESERVE_EXCEPTION_MARK; KlassHandle finalizer_klass(THREAD, SystemDictionary::finalizer_klass()); JavaValue result(T_VOID); JavaCalls::call_static( &result, finalizer_klass, vmSymbolHandles::run_finalizers_on_exit_name(), vmSymbolHandles::void_method_signature(), THREAD ); // Ignore any pending exceptions CLEAR_PENDING_EXCEPTION; } } // initialize_vtable could cause gc if // 1) we specified true to initialize_vtable and // 2) this ran after gc was enabled // In case those ever change we use handles for oops void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) { // init vtable of k and all subclasses Klass* ko = k_h()->klass_part(); klassVtable* vt = ko->vtable(); if (vt) vt->initialize_vtable(false, CHECK); if (ko->oop_is_instance()) { instanceKlass* ik = (instanceKlass*)ko; for (KlassHandle s_h(THREAD, ik->subklass()); s_h() != NULL; s_h = (THREAD, s_h()->klass_part()->next_sibling())) { reinitialize_vtable_of(s_h, CHECK); } } } void initialize_itable_for_klass(klassOop k, TRAPS) { instanceKlass::cast(k)->itable()->initialize_itable(false, CHECK); } void Universe::reinitialize_itables(TRAPS) { SystemDictionary::classes_do(initialize_itable_for_klass, CHECK); } bool Universe::on_page_boundary(void* addr) { return ((uintptr_t) addr) % os::vm_page_size() == 0; } bool Universe::should_fill_in_stack_trace(Handle throwable) { // never attempt to fill in the stack trace of preallocated errors that do not have // backtrace. These errors are kept alive forever and may be "re-used" when all // preallocated errors with backtrace have been consumed. Also need to avoid // a potential loop which could happen if an out of memory occurs when attempting // to allocate the backtrace. return ((throwable() != Universe::_out_of_memory_error_java_heap) && (throwable() != Universe::_out_of_memory_error_perm_gen) && (throwable() != Universe::_out_of_memory_error_array_size) && (throwable() != Universe::_out_of_memory_error_gc_overhead_limit)); } oop Universe::gen_out_of_memory_error(oop default_err) { // generate an out of memory error: // - if there is a preallocated error with backtrace available then return it wth // a filled in stack trace. // - if there are no preallocated errors with backtrace available then return // an error without backtrace. int next; if (_preallocated_out_of_memory_error_avail_count > 0) { next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count); assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt"); } else { next = -1; } if (next < 0) { // all preallocated errors have been used. // return default return default_err; } else { // get the error object at the slot and set set it to NULL so that the // array isn't keeping it alive anymore. oop exc = preallocated_out_of_memory_errors()->obj_at(next); assert(exc != NULL, "slot has been used already"); preallocated_out_of_memory_errors()->obj_at_put(next, NULL); // use the message from the default error oop msg = java_lang_Throwable::message(default_err); assert(msg != NULL, "no message"); java_lang_Throwable::set_message(exc, msg); // populate the stack trace and return it. java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc); return exc; } } static intptr_t non_oop_bits = 0; void* Universe::non_oop_word() { // Neither the high bits nor the low bits of this value is allowed // to look like (respectively) the high or low bits of a real oop. // // High and low are CPU-specific notions, but low always includes // the low-order bit. Since oops are always aligned at least mod 4, // setting the low-order bit will ensure that the low half of the // word will never look like that of a real oop. // // Using the OS-supplied non-memory-address word (usually 0 or -1) // will take care of the high bits, however many there are. if (non_oop_bits == 0) { non_oop_bits = (intptr_t)os::non_memory_address_word() | 1; } return (void*)non_oop_bits; } jint universe_init() { assert(!Universe::_fully_initialized, "called after initialize_vtables"); guarantee(1 << LogHeapWordSize == sizeof(HeapWord), "LogHeapWordSize is incorrect."); guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?"); guarantee(sizeof(oop) % sizeof(HeapWord) == 0, "oop size is not not a multiple of HeapWord size"); TraceTime timer("Genesis", TraceStartupTime); GC_locker::lock(); // do not allow gc during bootstrapping JavaClasses::compute_hard_coded_offsets(); // Get map info from shared archive file. if (DumpSharedSpaces) UseSharedSpaces = false; FileMapInfo* mapinfo = NULL; if (UseSharedSpaces) { mapinfo = NEW_C_HEAP_OBJ(FileMapInfo); memset(mapinfo, 0, sizeof(FileMapInfo)); // Open the shared archive file, read and validate the header. If // initialization files, shared spaces [UseSharedSpaces] are // disabled and the file is closed. if (mapinfo->initialize()) { FileMapInfo::set_current_info(mapinfo); } else { assert(!mapinfo->is_open() && !UseSharedSpaces, "archive file not closed or shared spaces not disabled."); } } jint status = Universe::initialize_heap(); if (status != JNI_OK) { return status; } // We have a heap so create the methodOop caches before // CompactingPermGenGen::initialize_oops() tries to populate them. Universe::_finalizer_register_cache = new LatestMethodOopCache(); Universe::_loader_addClass_cache = new LatestMethodOopCache(); Universe::_reflect_invoke_cache = new ActiveMethodOopsCache(); if (UseSharedSpaces) { // Read the data structures supporting the shared spaces (shared // system dictionary, symbol table, etc.). After that, access to // the file (other than the mapped regions) is no longer needed, and // the file is closed. Closing the file does not affect the // currently mapped regions. CompactingPermGenGen::initialize_oops(); mapinfo->close(); } else { SymbolTable::create_table(); StringTable::create_table(); ClassLoader::create_package_info_table(); } return JNI_OK; } // Choose the heap base address and oop encoding mode // when compressed oops are used: // Unscaled - Use 32-bits oops without encoding when // NarrowOopHeapBaseMin + heap_size < 4Gb // ZeroBased - Use zero based compressed oops with encoding when // NarrowOopHeapBaseMin + heap_size < 32Gb // HeapBased - Use compressed oops with heap base + encoding. // 4Gb static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1); // 32Gb static const uint64_t OopEncodingHeapMax = NarrowOopHeapMax << LogMinObjAlignmentInBytes; char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) { #ifdef _LP64 if (UseCompressedOops) { assert(mode == UnscaledNarrowOop || mode == ZeroBasedNarrowOop || mode == HeapBasedNarrowOop, "mode is invalid"); const size_t total_size = heap_size + HeapBaseMinAddress; if (total_size <= OopEncodingHeapMax && (mode != HeapBasedNarrowOop)) { if (total_size <= NarrowOopHeapMax && (mode == UnscaledNarrowOop) && (Universe::narrow_oop_shift() == 0)) { // Use 32-bits oops without encoding and // place heap's top on the 4Gb boundary return (char*)(NarrowOopHeapMax - heap_size); } else { // Can't reserve with NarrowOopShift == 0 Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); if (mode == UnscaledNarrowOop || mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) { // Use zero based compressed oops with encoding and // place heap's top on the 32Gb boundary in case // total_size > 4Gb or failed to reserve below 4Gb. return (char*)(OopEncodingHeapMax - heap_size); } } } else { // Can't reserve below 32Gb. Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); } } #endif return NULL; // also return NULL (don't care) for 32-bit VM } jint Universe::initialize_heap() { if (UseParallelGC) { #ifndef SERIALGC Universe::_collectedHeap = new ParallelScavengeHeap(); #else // SERIALGC fatal("UseParallelGC not supported in java kernel vm."); #endif // SERIALGC } else if (UseG1GC) { #ifndef SERIALGC G1CollectorPolicy* g1p = new G1CollectorPolicy_BestRegionsFirst(); G1CollectedHeap* g1h = new G1CollectedHeap(g1p); Universe::_collectedHeap = g1h; #else // SERIALGC fatal("UseG1GC not supported in java kernel vm."); #endif // SERIALGC } else { GenCollectorPolicy *gc_policy; if (UseSerialGC) { gc_policy = new MarkSweepPolicy(); } else if (UseConcMarkSweepGC) { #ifndef SERIALGC if (UseAdaptiveSizePolicy) { gc_policy = new ASConcurrentMarkSweepPolicy(); } else { gc_policy = new ConcurrentMarkSweepPolicy(); } #else // SERIALGC fatal("UseConcMarkSweepGC not supported in java kernel vm."); #endif // SERIALGC } else { // default old generation gc_policy = new MarkSweepPolicy(); } Universe::_collectedHeap = new GenCollectedHeap(gc_policy); } jint status = Universe::heap()->initialize(); if (status != JNI_OK) { return status; } #ifdef _LP64 if (UseCompressedOops) { // Subtract a page because something can get allocated at heap base. // This also makes implicit null checking work, because the // memory+1 page below heap_base needs to cause a signal. // See needs_explicit_null_check. // Only set the heap base for compressed oops because it indicates // compressed oops for pstack code. if (PrintCompressedOopsMode) { tty->cr(); tty->print("heap address: "PTR_FORMAT, Universe::heap()->base()); } if ((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax) { // Can't reserve heap below 32Gb. Universe::set_narrow_oop_base(Universe::heap()->base() - os::vm_page_size()); Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); if (PrintCompressedOopsMode) { tty->print(", Compressed Oops with base: "PTR_FORMAT, Universe::narrow_oop_base()); } } else { Universe::set_narrow_oop_base(0); if (PrintCompressedOopsMode) { tty->print(", zero based Compressed Oops"); } #ifdef _WIN64 if (!Universe::narrow_oop_use_implicit_null_checks()) { // Don't need guard page for implicit checks in indexed addressing // mode with zero based Compressed Oops. Universe::set_narrow_oop_use_implicit_null_checks(true); } #endif // _WIN64 if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) { // Can't reserve heap below 4Gb. Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes); } else { assert(Universe::narrow_oop_shift() == 0, "use unscaled narrow oop"); if (PrintCompressedOopsMode) { tty->print(", 32-bits Oops"); } } } if (PrintCompressedOopsMode) { tty->cr(); tty->cr(); } } assert(Universe::narrow_oop_base() == (Universe::heap()->base() - os::vm_page_size()) || Universe::narrow_oop_base() == NULL, "invalid value"); assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes || Universe::narrow_oop_shift() == 0, "invalid value"); #endif // We will never reach the CATCH below since Exceptions::_throw will cause // the VM to exit if an exception is thrown during initialization if (UseTLAB) { assert(Universe::heap()->supports_tlab_allocation(), "Should support thread-local allocation buffers"); ThreadLocalAllocBuffer::startup_initialization(); } return JNI_OK; } // It's the caller's repsonsibility to ensure glitch-freedom // (if required). void Universe::update_heap_info_at_gc() { _heap_capacity_at_last_gc = heap()->capacity(); _heap_used_at_last_gc = heap()->used(); } void universe2_init() { EXCEPTION_MARK; Universe::genesis(CATCH); // Although we'd like to verify here that the state of the heap // is good, we can't because the main thread has not yet added // itself to the threads list (so, using current interfaces // we can't "fill" its TLAB), unless TLABs are disabled. if (VerifyBeforeGC && !UseTLAB && Universe::heap()->total_collections() >= VerifyGCStartAt) { Universe::heap()->prepare_for_verify(); Universe::verify(); // make sure we're starting with a clean slate } } // This function is defined in JVM.cpp extern void initialize_converter_functions(); bool universe_post_init() { Universe::_fully_initialized = true; EXCEPTION_MARK; { ResourceMark rm; Interpreter::initialize(); // needed for interpreter entry points if (!UseSharedSpaces) { KlassHandle ok_h(THREAD, SystemDictionary::object_klass()); Universe::reinitialize_vtable_of(ok_h, CHECK_false); Universe::reinitialize_itables(CHECK_false); } } klassOop k; instanceKlassHandle k_h; if (!UseSharedSpaces) { // Setup preallocated empty java.lang.Class array Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::class_klass(), 0, CHECK_false); // Setup preallocated OutOfMemoryError errors k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_OutOfMemoryError(), true, CHECK_false); k_h = instanceKlassHandle(THREAD, k); Universe::_out_of_memory_error_java_heap = k_h->allocate_permanent_instance(CHECK_false); Universe::_out_of_memory_error_perm_gen = k_h->allocate_permanent_instance(CHECK_false); Universe::_out_of_memory_error_array_size = k_h->allocate_permanent_instance(CHECK_false); Universe::_out_of_memory_error_gc_overhead_limit = k_h->allocate_permanent_instance(CHECK_false); // Setup preallocated NullPointerException // (this is currently used for a cheap & dirty solution in compiler exception handling) k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_NullPointerException(), true, CHECK_false); Universe::_null_ptr_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); // Setup preallocated ArithmeticException // (this is currently used for a cheap & dirty solution in compiler exception handling) k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_ArithmeticException(), true, CHECK_false); Universe::_arithmetic_exception_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); // Virtual Machine Error for when we get into a situation we can't resolve k = SystemDictionary::resolve_or_fail( vmSymbolHandles::java_lang_VirtualMachineError(), true, CHECK_false); bool linked = instanceKlass::cast(k)->link_class_or_fail(CHECK_false); if (!linked) { tty->print_cr("Unable to link/verify VirtualMachineError class"); return false; // initialization failed } Universe::_virtual_machine_error_instance = instanceKlass::cast(k)->allocate_permanent_instance(CHECK_false); } if (!DumpSharedSpaces) { // These are the only Java fields that are currently set during shared space dumping. // We prefer to not handle this generally, so we always reinitialize these detail messages. Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false); java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg()); msg = java_lang_String::create_from_str("PermGen space", CHECK_false); java_lang_Throwable::set_message(Universe::_out_of_memory_error_perm_gen, msg()); msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false); java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg()); msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false); java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg()); msg = java_lang_String::create_from_str("/ by zero", CHECK_false); java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg()); // Setup the array of errors that have preallocated backtrace k = Universe::_out_of_memory_error_java_heap->klass(); assert(k->klass_part()->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error"); k_h = instanceKlassHandle(THREAD, k); int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0; Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false); for (int i=0; iallocate_permanent_instance(CHECK_false); Handle err_h = Handle(THREAD, err); java_lang_Throwable::allocate_backtrace(err_h, CHECK_false); Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h()); } Universe::_preallocated_out_of_memory_error_avail_count = (jint)len; } // Setup static method for registering finalizers // The finalizer klass must be linked before looking up the method, in // case it needs to get rewritten. instanceKlass::cast(SystemDictionary::finalizer_klass())->link_class(CHECK_false); methodOop m = instanceKlass::cast(SystemDictionary::finalizer_klass())->find_method( vmSymbols::register_method_name(), vmSymbols::register_method_signature()); if (m == NULL || !m->is_static()) { THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), "java.lang.ref.Finalizer.register", false); } Universe::_finalizer_register_cache->init( SystemDictionary::finalizer_klass(), m, CHECK_false); // Resolve on first use and initialize class. // Note: No race-condition here, since a resolve will always return the same result // Setup method for security checks k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_reflect_Method(), true, CHECK_false); k_h = instanceKlassHandle(THREAD, k); k_h->link_class(CHECK_false); m = k_h->find_method(vmSymbols::invoke_name(), vmSymbols::object_array_object_object_signature()); if (m == NULL || m->is_static()) { THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), "java.lang.reflect.Method.invoke", false); } Universe::_reflect_invoke_cache->init(k_h(), m, CHECK_false); // Setup method for registering loaded classes in class loader vector instanceKlass::cast(SystemDictionary::classloader_klass())->link_class(CHECK_false); m = instanceKlass::cast(SystemDictionary::classloader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature()); if (m == NULL || m->is_static()) { THROW_MSG_(vmSymbols::java_lang_NoSuchMethodException(), "java.lang.ClassLoader.addClass", false); } Universe::_loader_addClass_cache->init( SystemDictionary::classloader_klass(), m, CHECK_false); // The folowing is initializing converter functions for serialization in // JVM.cpp. If we clean up the StrictMath code above we may want to find // a better solution for this as well. initialize_converter_functions(); // This needs to be done before the first scavenge/gc, since // it's an input to soft ref clearing policy. { MutexLocker x(Heap_lock); Universe::update_heap_info_at_gc(); } // ("weak") refs processing infrastructure initialization Universe::heap()->post_initialize(); GC_locker::unlock(); // allow gc after bootstrapping MemoryService::set_universe_heap(Universe::_collectedHeap); return true; } void Universe::compute_base_vtable_size() { _base_vtable_size = ClassLoader::compute_Object_vtable(); } // %%% The Universe::flush_foo methods belong in CodeCache. // Flushes compiled methods dependent on dependee. void Universe::flush_dependents_on(instanceKlassHandle dependee) { assert_lock_strong(Compile_lock); if (CodeCache::number_of_nmethods_with_dependencies() == 0) return; // CodeCache can only be updated by a thread_in_VM and they will all be // stopped dring the safepoint so CodeCache will be safe to update without // holding the CodeCache_lock. DepChange changes(dependee); // Compute the dependent nmethods if (CodeCache::mark_for_deoptimization(changes) > 0) { // At least one nmethod has been marked for deoptimization VM_Deoptimize op; VMThread::execute(&op); } } #ifdef HOTSWAP // Flushes compiled methods dependent on dependee in the evolutionary sense void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) { // --- Compile_lock is not held. However we are at a safepoint. assert_locked_or_safepoint(Compile_lock); if (CodeCache::number_of_nmethods_with_dependencies() == 0) return; // CodeCache can only be updated by a thread_in_VM and they will all be // stopped dring the safepoint so CodeCache will be safe to update without // holding the CodeCache_lock. // Compute the dependent nmethods if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) { // At least one nmethod has been marked for deoptimization // All this already happens inside a VM_Operation, so we'll do all the work here. // Stuff copied from VM_Deoptimize and modified slightly. // We do not want any GCs to happen while we are in the middle of this VM operation ResourceMark rm; DeoptimizationMarker dm; // Deoptimize all activations depending on marked nmethods Deoptimization::deoptimize_dependents(); // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies) CodeCache::make_marked_nmethods_not_entrant(); } } #endif // HOTSWAP // Flushes compiled methods dependent on dependee void Universe::flush_dependents_on_method(methodHandle m_h) { // --- Compile_lock is not held. However we are at a safepoint. assert_locked_or_safepoint(Compile_lock); // CodeCache can only be updated by a thread_in_VM and they will all be // stopped dring the safepoint so CodeCache will be safe to update without // holding the CodeCache_lock. // Compute the dependent nmethods if (CodeCache::mark_for_deoptimization(m_h()) > 0) { // At least one nmethod has been marked for deoptimization // All this already happens inside a VM_Operation, so we'll do all the work here. // Stuff copied from VM_Deoptimize and modified slightly. // We do not want any GCs to happen while we are in the middle of this VM operation ResourceMark rm; DeoptimizationMarker dm; // Deoptimize all activations depending on marked nmethods Deoptimization::deoptimize_dependents(); // Make the dependent methods not entrant (in VM_Deoptimize they are made zombies) CodeCache::make_marked_nmethods_not_entrant(); } } void Universe::print() { print_on(gclog_or_tty); } void Universe::print_on(outputStream* st) { st->print_cr("Heap"); heap()->print_on(st); } void Universe::print_heap_at_SIGBREAK() { if (PrintHeapAtSIGBREAK) { MutexLocker hl(Heap_lock); print_on(tty); tty->cr(); tty->flush(); } } void Universe::print_heap_before_gc(outputStream* st) { st->print_cr("{Heap before GC invocations=%u (full %u):", heap()->total_collections(), heap()->total_full_collections()); heap()->print_on(st); } void Universe::print_heap_after_gc(outputStream* st) { st->print_cr("Heap after GC invocations=%u (full %u):", heap()->total_collections(), heap()->total_full_collections()); heap()->print_on(st); st->print_cr("}"); } void Universe::verify(bool allow_dirty, bool silent, bool option) { if (SharedSkipVerify) { return; } // The use of _verify_in_progress is a temporary work around for // 6320749. Don't bother with a creating a class to set and clear // it since it is only used in this method and the control flow is // straight forward. _verify_in_progress = true; COMPILER2_PRESENT( assert(!DerivedPointerTable::is_active(), "DPT should not be active during verification " "(of thread stacks below)"); ) ResourceMark rm; HandleMark hm; // Handles created during verification can be zapped _verify_count++; if (!silent) gclog_or_tty->print("[Verifying "); if (!silent) gclog_or_tty->print("threads "); Threads::verify(); heap()->verify(allow_dirty, silent, option); if (!silent) gclog_or_tty->print("syms "); SymbolTable::verify(); if (!silent) gclog_or_tty->print("strs "); StringTable::verify(); { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); if (!silent) gclog_or_tty->print("zone "); CodeCache::verify(); } if (!silent) gclog_or_tty->print("dict "); SystemDictionary::verify(); if (!silent) gclog_or_tty->print("hand "); JNIHandles::verify(); if (!silent) gclog_or_tty->print("C-heap "); os::check_heap(); if (!silent) gclog_or_tty->print_cr("]"); _verify_in_progress = false; } // Oop verification (see MacroAssembler::verify_oop) static uintptr_t _verify_oop_data[2] = {0, (uintptr_t)-1}; static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1}; static void calculate_verify_data(uintptr_t verify_data[2], HeapWord* low_boundary, HeapWord* high_boundary) { assert(low_boundary < high_boundary, "bad interval"); // decide which low-order bits we require to be clear: size_t alignSize = MinObjAlignmentInBytes; size_t min_object_size = oopDesc::header_size(); // make an inclusive limit: uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize; uintptr_t min = (uintptr_t)low_boundary; assert(min < max, "bad interval"); uintptr_t diff = max ^ min; // throw away enough low-order bits to make the diff vanish uintptr_t mask = (uintptr_t)(-1); while ((mask & diff) != 0) mask <<= 1; uintptr_t bits = (min & mask); assert(bits == (max & mask), "correct mask"); // check an intermediate value between min and max, just to make sure: assert(bits == ((min + (max-min)/2) & mask), "correct mask"); // require address alignment, too: mask |= (alignSize - 1); if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) { assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability"); } verify_data[0] = mask; verify_data[1] = bits; } // Oop verification (see MacroAssembler::verify_oop) #ifndef PRODUCT uintptr_t Universe::verify_oop_mask() { MemRegion m = heap()->reserved_region(); calculate_verify_data(_verify_oop_data, m.start(), m.end()); return _verify_oop_data[0]; } uintptr_t Universe::verify_oop_bits() { verify_oop_mask(); return _verify_oop_data[1]; } uintptr_t Universe::verify_klass_mask() { /* $$$ // A klass can never live in the new space. Since the new and old // spaces can change size, we must settle for bounds-checking against // the bottom of the world, plus the smallest possible new and old // space sizes that may arise during execution. size_t min_new_size = Universe::new_size(); // in bytes size_t min_old_size = Universe::old_size(); // in bytes calculate_verify_data(_verify_klass_data, (HeapWord*)((uintptr_t)_new_gen->low_boundary + min_new_size + min_old_size), _perm_gen->high_boundary); */ // Why doesn't the above just say that klass's always live in the perm // gen? I'll see if that seems to work... MemRegion permanent_reserved; switch (Universe::heap()->kind()) { default: // ???: What if a CollectedHeap doesn't have a permanent generation? ShouldNotReachHere(); break; case CollectedHeap::GenCollectedHeap: case CollectedHeap::G1CollectedHeap: { SharedHeap* sh = (SharedHeap*) Universe::heap(); permanent_reserved = sh->perm_gen()->reserved(); break; } #ifndef SERIALGC case CollectedHeap::ParallelScavengeHeap: { ParallelScavengeHeap* psh = (ParallelScavengeHeap*) Universe::heap(); permanent_reserved = psh->perm_gen()->reserved(); break; } #endif // SERIALGC } calculate_verify_data(_verify_klass_data, permanent_reserved.start(), permanent_reserved.end()); return _verify_klass_data[0]; } uintptr_t Universe::verify_klass_bits() { verify_klass_mask(); return _verify_klass_data[1]; } uintptr_t Universe::verify_mark_mask() { return markOopDesc::lock_mask_in_place; } uintptr_t Universe::verify_mark_bits() { intptr_t mask = verify_mark_mask(); intptr_t bits = (intptr_t)markOopDesc::prototype(); assert((bits & ~mask) == 0, "no stray header bits"); return bits; } #endif // PRODUCT void Universe::compute_verify_oop_data() { verify_oop_mask(); verify_oop_bits(); verify_mark_mask(); verify_mark_bits(); verify_klass_mask(); verify_klass_bits(); } void CommonMethodOopCache::init(klassOop k, methodOop m, TRAPS) { if (!UseSharedSpaces) { _klass = k; } #ifndef PRODUCT else { // sharing initilization should have already set up _klass assert(_klass != NULL, "just checking"); } #endif _method_idnum = m->method_idnum(); assert(_method_idnum >= 0, "sanity check"); } ActiveMethodOopsCache::~ActiveMethodOopsCache() { if (_prev_methods != NULL) { for (int i = _prev_methods->length() - 1; i >= 0; i--) { jweak method_ref = _prev_methods->at(i); if (method_ref != NULL) { JNIHandles::destroy_weak_global(method_ref); } } delete _prev_methods; _prev_methods = NULL; } } void ActiveMethodOopsCache::add_previous_version(const methodOop method) { assert(Thread::current()->is_VM_thread(), "only VMThread can add previous versions"); if (_prev_methods == NULL) { // This is the first previous version so make some space. // Start with 2 elements under the assumption that the class // won't be redefined much. _prev_methods = new (ResourceObj::C_HEAP) GrowableArray(2, true); } // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00000100, ("add: %s(%s): adding prev version ref for cached method @%d", method->name()->as_C_string(), method->signature()->as_C_string(), _prev_methods->length())); methodHandle method_h(method); jweak method_ref = JNIHandles::make_weak_global(method_h); _prev_methods->append(method_ref); // Using weak references allows previous versions of the cached // method to be GC'ed when they are no longer needed. Since the // caller is the VMThread and we are at a safepoint, this is a good // time to clear out unused weak references. for (int i = _prev_methods->length() - 1; i >= 0; i--) { jweak method_ref = _prev_methods->at(i); assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); if (method_ref == NULL) { _prev_methods->remove_at(i); // Since we are traversing the array backwards, we don't have to // do anything special with the index. continue; // robustness } methodOop m = (methodOop)JNIHandles::resolve(method_ref); if (m == NULL) { // this method entry has been GC'ed so remove it JNIHandles::destroy_weak_global(method_ref); _prev_methods->remove_at(i); } else { // RC_TRACE macro has an embedded ResourceMark RC_TRACE(0x00000400, ("add: %s(%s): previous cached method @%d is alive", m->name()->as_C_string(), m->signature()->as_C_string(), i)); } } } // end add_previous_version() bool ActiveMethodOopsCache::is_same_method(const methodOop method) const { instanceKlass* ik = instanceKlass::cast(klass()); methodOop check_method = ik->method_with_idnum(method_idnum()); assert(check_method != NULL, "sanity check"); if (check_method == method) { // done with the easy case return true; } if (_prev_methods != NULL) { // The cached method has been redefined at least once so search // the previous versions for a match. for (int i = 0; i < _prev_methods->length(); i++) { jweak method_ref = _prev_methods->at(i); assert(method_ref != NULL, "weak method ref was unexpectedly cleared"); if (method_ref == NULL) { continue; // robustness } check_method = (methodOop)JNIHandles::resolve(method_ref); if (check_method == method) { // a previous version matches return true; } } } // either no previous versions or no previous version matched return false; } methodOop LatestMethodOopCache::get_methodOop() { instanceKlass* ik = instanceKlass::cast(klass()); methodOop m = ik->method_with_idnum(method_idnum()); assert(m != NULL, "sanity check"); return m; } #ifdef ASSERT // Release dummy object(s) at bottom of heap bool Universe::release_fullgc_alot_dummy() { MutexLocker ml(FullGCALot_lock); if (_fullgc_alot_dummy_array != NULL) { if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) { // No more dummies to release, release entire array instead _fullgc_alot_dummy_array = NULL; return false; } if (!UseConcMarkSweepGC) { // Release dummy at bottom of old generation _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL); } // Release dummy at bottom of permanent generation _fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL); } return true; } #endif // ASSERT