/*
* Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "cds/archiveHeapLoader.hpp"
#include "cds/dynamicArchive.hpp"
#include "cds/heapShared.hpp"
#include "cds/metaspaceShared.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderDataGraph.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/stringTable.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmClasses.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeBehaviours.hpp"
#include "code/codeCache.hpp"
#include "compiler/oopMap.hpp"
#include "gc/shared/collectedHeap.inline.hpp"
#include "gc/shared/gcArguments.hpp"
#include "gc/shared/gcConfig.hpp"
#include "gc/shared/gcLogPrecious.hpp"
#include "gc/shared/gcTraceTime.inline.hpp"
#include "gc/shared/oopStorageSet.hpp"
#include "gc/shared/plab.hpp"
#include "gc/shared/stringdedup/stringDedup.hpp"
#include "gc/shared/tlab_globals.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/metaspaceCounters.hpp"
#include "memory/metaspaceUtils.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/compressedOops.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/instanceMirrorKlass.hpp"
#include "oops/klass.inline.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oopHandle.inline.hpp"
#include "oops/typeArrayKlass.hpp"
#include "prims/resolvedMethodTable.hpp"
#include "runtime/arguments.hpp"
#include "runtime/atomic.hpp"
#include "runtime/flags/jvmFlagLimit.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/init.hpp"
#include "runtime/java.hpp"
#include "runtime/javaThread.hpp"
#include "runtime/jniHandles.hpp"
#include "runtime/threads.hpp"
#include "runtime/timerTrace.hpp"
#include "services/memoryService.hpp"
#include "utilities/align.hpp"
#include "utilities/autoRestore.hpp"
#include "utilities/debug.hpp"
#include "utilities/formatBuffer.hpp"
#include "utilities/macros.hpp"
#include "utilities/ostream.hpp"
#include "utilities/preserveException.hpp"
// Known objects
Klass* Universe::_typeArrayKlassObjs[T_LONG+1] = { NULL /*, NULL...*/ };
Klass* Universe::_objectArrayKlassObj = NULL;
Klass* Universe::_fillerArrayKlassObj = NULL;
OopHandle Universe::_basic_type_mirrors[T_VOID+1];
#if INCLUDE_CDS_JAVA_HEAP
int Universe::_archived_basic_type_mirror_indices[T_VOID+1];
#endif
OopHandle Universe::_main_thread_group;
OopHandle Universe::_system_thread_group;
OopHandle Universe::_the_empty_class_array;
OopHandle Universe::_the_null_string;
OopHandle Universe::_the_min_jint_string;
OopHandle Universe::_the_null_sentinel;
// _out_of_memory_errors is an objArray
enum OutOfMemoryInstance { _oom_java_heap,
_oom_c_heap,
_oom_metaspace,
_oom_class_metaspace,
_oom_array_size,
_oom_gc_overhead_limit,
_oom_realloc_objects,
_oom_retry,
_oom_count };
OopHandle Universe::_out_of_memory_errors;
OopHandle Universe::_delayed_stack_overflow_error_message;
OopHandle Universe::_preallocated_out_of_memory_error_array;
volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
// Message details for OOME objects, preallocate these objects since they could be
// used when throwing OOME, we should try to avoid further allocation in such case
OopHandle Universe::_msg_metaspace;
OopHandle Universe::_msg_class_metaspace;
OopHandle Universe::_null_ptr_exception_instance;
OopHandle Universe::_arithmetic_exception_instance;
OopHandle Universe::_virtual_machine_error_instance;
OopHandle Universe::_reference_pending_list;
Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
LatestMethodCache* Universe::_finalizer_register_cache = NULL;
LatestMethodCache* Universe::_loader_addClass_cache = NULL;
LatestMethodCache* Universe::_throw_illegal_access_error_cache = NULL;
LatestMethodCache* Universe::_throw_no_such_method_error_cache = NULL;
LatestMethodCache* Universe::_do_stack_walk_cache = NULL;
long Universe::verify_flags = Universe::Verify_All;
Array<int>* Universe::_the_empty_int_array = NULL;
Array<u2>* Universe::_the_empty_short_array = NULL;
Array<Klass*>* Universe::_the_empty_klass_array = NULL;
Array<InstanceKlass*>* Universe::_the_empty_instance_klass_array = NULL;
Array<Method*>* Universe::_the_empty_method_array = NULL;
// These variables are guarded by FullGCALot_lock.
debug_only(OopHandle Universe::_fullgc_alot_dummy_array;)
debug_only(int Universe::_fullgc_alot_dummy_next = 0;)
// Heap
int Universe::_verify_count = 0;
// Oop verification (see MacroAssembler::verify_oop)
uintptr_t Universe::_verify_oop_mask = 0;
uintptr_t Universe::_verify_oop_bits = (uintptr_t) -1;
int Universe::_base_vtable_size = 0;
bool Universe::_bootstrapping = false;
bool Universe::_module_initialized = false;
bool Universe::_fully_initialized = false;
OopStorage* Universe::_vm_weak = NULL;
OopStorage* Universe::_vm_global = NULL;
CollectedHeap* Universe::_collectedHeap = NULL;
objArrayOop Universe::the_empty_class_array () {
return (objArrayOop)_the_empty_class_array.resolve();
}
oop Universe::main_thread_group() { return _main_thread_group.resolve(); }
void Universe::set_main_thread_group(oop group) { _main_thread_group = OopHandle(vm_global(), group); }
oop Universe::system_thread_group() { return _system_thread_group.resolve(); }
void Universe::set_system_thread_group(oop group) { _system_thread_group = OopHandle(vm_global(), group); }
oop Universe::the_null_string() { return _the_null_string.resolve(); }
oop Universe::the_min_jint_string() { return _the_min_jint_string.resolve(); }
oop Universe::null_ptr_exception_instance() { return _null_ptr_exception_instance.resolve(); }
oop Universe::arithmetic_exception_instance() { return _arithmetic_exception_instance.resolve(); }
oop Universe::virtual_machine_error_instance() { return _virtual_machine_error_instance.resolve(); }
oop Universe::the_null_sentinel() { return _the_null_sentinel.resolve(); }
oop Universe::int_mirror() { return check_mirror(_basic_type_mirrors[T_INT].resolve()); }
oop Universe::float_mirror() { return check_mirror(_basic_type_mirrors[T_FLOAT].resolve()); }
oop Universe::double_mirror() { return check_mirror(_basic_type_mirrors[T_DOUBLE].resolve()); }
oop Universe::byte_mirror() { return check_mirror(_basic_type_mirrors[T_BYTE].resolve()); }
oop Universe::bool_mirror() { return check_mirror(_basic_type_mirrors[T_BOOLEAN].resolve()); }
oop Universe::char_mirror() { return check_mirror(_basic_type_mirrors[T_CHAR].resolve()); }
oop Universe::long_mirror() { return check_mirror(_basic_type_mirrors[T_LONG].resolve()); }
oop Universe::short_mirror() { return check_mirror(_basic_type_mirrors[T_SHORT].resolve()); }
oop Universe::void_mirror() { return check_mirror(_basic_type_mirrors[T_VOID].resolve()); }
oop Universe::java_mirror(BasicType t) {
assert((uint)t < T_VOID+1, "range check");
assert(!is_reference_type(t), "sanity");
return check_mirror(_basic_type_mirrors[t].resolve());
}
void Universe::basic_type_classes_do(KlassClosure *closure) {
for (int i = T_BOOLEAN; i < T_LONG+1; i++) {
closure->do_klass(_typeArrayKlassObjs[i]);
}
// We don't do the following because it will confuse JVMTI.
// _fillerArrayKlassObj is used only by GC, which doesn't need to see
// this klass from basic_type_classes_do().
//
// closure->do_klass(_fillerArrayKlassObj);
}
void LatestMethodCache::metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_klass);
}
void Universe::metaspace_pointers_do(MetaspaceClosure* it) {
it->push(&_fillerArrayKlassObj);
for (int i = 0; i < T_LONG+1; i++) {
it->push(&_typeArrayKlassObjs[i]);
}
it->push(&_objectArrayKlassObj);
it->push(&_the_empty_int_array);
it->push(&_the_empty_short_array);
it->push(&_the_empty_klass_array);
it->push(&_the_empty_instance_klass_array);
it->push(&_the_empty_method_array);
it->push(&_the_array_interfaces_array);
_finalizer_register_cache->metaspace_pointers_do(it);
_loader_addClass_cache->metaspace_pointers_do(it);
_throw_illegal_access_error_cache->metaspace_pointers_do(it);
_throw_no_such_method_error_cache->metaspace_pointers_do(it);
_do_stack_walk_cache->metaspace_pointers_do(it);
}
#if INCLUDE_CDS_JAVA_HEAP
void Universe::set_archived_basic_type_mirror_index(BasicType t, int index) {
assert(DumpSharedSpaces, "dump-time only");
assert(!is_reference_type(t), "sanity");
_archived_basic_type_mirror_indices[t] = index;
}
void Universe::update_archived_basic_type_mirrors() {
if (ArchiveHeapLoader::are_archived_mirrors_available()) {
for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
int index = _archived_basic_type_mirror_indices[i];
if (!is_reference_type((BasicType)i) && index >= 0) {
oop mirror_oop = HeapShared::get_root(index);
assert(mirror_oop != NULL, "must be");
_basic_type_mirrors[i] = OopHandle(vm_global(), mirror_oop);
}
}
}
}
#endif
void Universe::serialize(SerializeClosure* f) {
#if INCLUDE_CDS_JAVA_HEAP
for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
f->do_u4((u4*)&_archived_basic_type_mirror_indices[i]);
// if f->reading(): We can't call HeapShared::get_root() yet, as the heap
// contents may need to be relocated. _basic_type_mirrors[i] will be
// updated later in Universe::update_archived_basic_type_mirrors().
}
#endif
f->do_ptr((void**)&_fillerArrayKlassObj);
for (int i = 0; i < T_LONG+1; i++) {
f->do_ptr((void**)&_typeArrayKlassObjs[i]);
}
f->do_ptr((void**)&_objectArrayKlassObj);
f->do_ptr((void**)&_the_array_interfaces_array);
f->do_ptr((void**)&_the_empty_int_array);
f->do_ptr((void**)&_the_empty_short_array);
f->do_ptr((void**)&_the_empty_method_array);
f->do_ptr((void**)&_the_empty_klass_array);
f->do_ptr((void**)&_the_empty_instance_klass_array);
_finalizer_register_cache->serialize(f);
_loader_addClass_cache->serialize(f);
_throw_illegal_access_error_cache->serialize(f);
_throw_no_such_method_error_cache->serialize(f);
_do_stack_walk_cache->serialize(f);
}
void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
if (size < alignment || size % alignment != 0) {
vm_exit_during_initialization(
err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
}
}
void initialize_basic_type_klass(Klass* k, TRAPS) {
Klass* ok = vmClasses::Object_klass();
#if INCLUDE_CDS
if (UseSharedSpaces) {
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
assert(k->super() == ok, "u3");
if (k->is_instance_klass()) {
InstanceKlass::cast(k)->restore_unshareable_info(loader_data, Handle(), NULL, CHECK);
} else {
ArrayKlass::cast(k)->restore_unshareable_info(loader_data, Handle(), CHECK);
}
} else
#endif
{
k->initialize_supers(ok, NULL, CHECK);
}
k->append_to_sibling_list();
}
void Universe::genesis(TRAPS) {
ResourceMark rm(THREAD);
HandleMark hm(THREAD);
{ AutoModifyRestore<bool> temporarily(_bootstrapping, true);
{ MutexLocker mc(THREAD, Compile_lock);
java_lang_Class::allocate_fixup_lists();
// determine base vtable size; without that we cannot create the array klasses
compute_base_vtable_size();
if (!UseSharedSpaces) {
// Initialization of the fillerArrayKlass must come before regular
// int-TypeArrayKlass so that the int-Array mirror points to the
// int-TypeArrayKlass.
_fillerArrayKlassObj = TypeArrayKlass::create_klass(T_INT, "Ljdk/internal/vm/FillerArray;", CHECK);
for (int i = T_BOOLEAN; i < T_LONG+1; i++) {
_typeArrayKlassObjs[i] = TypeArrayKlass::create_klass((BasicType)i, CHECK);
}
ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
_the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
_the_empty_int_array = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
_the_empty_short_array = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
_the_empty_method_array = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
_the_empty_klass_array = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
_the_empty_instance_klass_array = MetadataFactory::new_array<InstanceKlass*>(null_cld, 0, CHECK);
}
}
vmSymbols::initialize();
SystemDictionary::initialize(CHECK);
// Create string constants
oop s = StringTable::intern("null", CHECK);
_the_null_string = OopHandle(vm_global(), s);
s = StringTable::intern("-2147483648", CHECK);
_the_min_jint_string = OopHandle(vm_global(), s);
#if INCLUDE_CDS
if (UseSharedSpaces) {
// Verify shared interfaces array.
assert(_the_array_interfaces_array->at(0) ==
vmClasses::Cloneable_klass(), "u3");
assert(_the_array_interfaces_array->at(1) ==
vmClasses::Serializable_klass(), "u3");
} else
#endif
{
// Set up shared interfaces array. (Do this before supers are set up.)
_the_array_interfaces_array->at_put(0, vmClasses::Cloneable_klass());
_the_array_interfaces_array->at_put(1, vmClasses::Serializable_klass());
}
initialize_basic_type_klass(_fillerArrayKlassObj, CHECK);
initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
initialize_basic_type_klass(charArrayKlassObj(), CHECK);
initialize_basic_type_klass(floatArrayKlassObj(), CHECK);
initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
initialize_basic_type_klass(intArrayKlassObj(), CHECK);
initialize_basic_type_klass(longArrayKlassObj(), CHECK);
assert(_fillerArrayKlassObj != intArrayKlassObj(),
"Internal filler array klass should be different to int array Klass");
} // end of core bootstrapping
{
Handle tns = java_lang_String::create_from_str("", CHECK);
_the_null_sentinel = OopHandle(vm_global(), tns());
}
// Create a handle for reference_pending_list
_reference_pending_list = OopHandle(vm_global(), NULL);
// Maybe this could be lifted up now that object array can be initialized
// during the bootstrapping.
// OLD
// Initialize _objectArrayKlass after core bootstraping to make
// sure the super class is set up properly for _objectArrayKlass.
// ---
// NEW
// Since some of the old system object arrays have been converted to
// ordinary object arrays, _objectArrayKlass will be loaded when
// SystemDictionary::initialize(CHECK); is run. See the extra check
// for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
_objectArrayKlassObj = InstanceKlass::
cast(vmClasses::Object_klass())->array_klass(1, CHECK);
// OLD
// Add the class to the class hierarchy manually to make sure that
// its vtable is initialized after core bootstrapping is completed.
// ---
// New
// Have already been initialized.
_objectArrayKlassObj->append_to_sibling_list();
#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.
int size = FullGCALotDummies * 2;
objArrayOop naked_array = oopFactory::new_objArray(vmClasses::Object_klass(), size, CHECK);
objArrayHandle dummy_array(THREAD, naked_array);
int i = 0;
while (i < size) {
// Allocate dummy in old generation
oop dummy = vmClasses::Object_klass()->allocate_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(THREAD, FullGCALot_lock);
if (_fullgc_alot_dummy_array.is_empty()) {
_fullgc_alot_dummy_array = OopHandle(vm_global(), dummy_array());
}
}
assert(i == ((objArrayOop)_fullgc_alot_dummy_array.resolve())->length(), "just checking");
}
#endif
}
void Universe::initialize_basic_type_mirrors(TRAPS) {
#if INCLUDE_CDS_JAVA_HEAP
if (UseSharedSpaces &&
ArchiveHeapLoader::are_archived_mirrors_available() &&
_basic_type_mirrors[T_INT].resolve() != NULL) {
assert(ArchiveHeapLoader::can_use(), "Sanity");
// check that all basic type mirrors are mapped also
for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
if (!is_reference_type((BasicType)i)) {
oop m = _basic_type_mirrors[i].resolve();
assert(m != NULL, "archived mirrors should not be NULL");
}
}
} else
// _basic_type_mirrors[T_INT], etc, are NULL if archived heap is not mapped.
#endif
{
for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
BasicType bt = (BasicType)i;
if (!is_reference_type(bt)) {
oop m = java_lang_Class::create_basic_type_mirror(type2name(bt), bt, CHECK);
_basic_type_mirrors[i] = OopHandle(vm_global(), m);
}
CDS_JAVA_HEAP_ONLY(_archived_basic_type_mirror_indices[i] = -1);
}
}
}
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(vmClasses::Class_klass_loaded(), "java.lang.Class should be loaded");
HandleMark hm(THREAD);
if (!UseSharedSpaces) {
// Cache the start of the static fields
InstanceMirrorKlass::init_offset_of_static_fields();
}
GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
int list_length = list->length();
for (int i = 0; i < list_length; i++) {
Klass* k = list->at(i);
assert(k->is_klass(), "List should only hold classes");
java_lang_Class::fixup_mirror(k, CATCH);
}
delete java_lang_Class::fixup_mirror_list();
java_lang_Class::set_fixup_mirror_list(NULL);
}
#define assert_pll_locked(test) \
assert(Heap_lock->test(), "Reference pending list access requires lock")
#define assert_pll_ownership() assert_pll_locked(owned_by_self)
oop Universe::reference_pending_list() {
if (Thread::current()->is_VM_thread()) {
assert_pll_locked(is_locked);
} else {
assert_pll_ownership();
}
return _reference_pending_list.resolve();
}
void Universe::clear_reference_pending_list() {
assert_pll_ownership();
_reference_pending_list.replace(NULL);
}
bool Universe::has_reference_pending_list() {
assert_pll_ownership();
return _reference_pending_list.peek() != NULL;
}
oop Universe::swap_reference_pending_list(oop list) {
assert_pll_locked(is_locked);
return _reference_pending_list.xchg(list);
}
#undef assert_pll_locked
#undef assert_pll_ownership
static void reinitialize_vtables() {
// The vtables are initialized by starting at java.lang.Object and
// initializing through the subclass links, so that the super
// classes are always initialized first.
for (ClassHierarchyIterator iter(vmClasses::Object_klass()); !iter.done(); iter.next()) {
Klass* sub = iter.klass();
sub->vtable().initialize_vtable();
}
}
static void reinitialize_itables() {
class ReinitTableClosure : public KlassClosure {
public:
void do_klass(Klass* k) {
if (k->is_instance_klass()) {
InstanceKlass::cast(k)->itable().initialize_itable();
}
}
};
MutexLocker mcld(ClassLoaderDataGraph_lock);
ReinitTableClosure cl;
ClassLoaderDataGraph::classes_do(&cl);
}
bool Universe::on_page_boundary(void* addr) {
return is_aligned(addr, os::vm_page_size());
}
// the array of preallocated errors with backtraces
objArrayOop Universe::preallocated_out_of_memory_errors() {
return (objArrayOop)_preallocated_out_of_memory_error_array.resolve();
}
objArrayOop Universe::out_of_memory_errors() { return (objArrayOop)_out_of_memory_errors.resolve(); }
oop Universe::out_of_memory_error_java_heap() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_java_heap));
}
oop Universe::out_of_memory_error_c_heap() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_c_heap));
}
oop Universe::out_of_memory_error_metaspace() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_metaspace));
}
oop Universe::out_of_memory_error_class_metaspace() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_class_metaspace));
}
oop Universe::out_of_memory_error_array_size() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_array_size));
}
oop Universe::out_of_memory_error_gc_overhead_limit() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_gc_overhead_limit));
}
oop Universe::out_of_memory_error_realloc_objects() {
return gen_out_of_memory_error(out_of_memory_errors()->obj_at(_oom_realloc_objects));
}
// Throw default _out_of_memory_error_retry object as it will never propagate out of the VM
oop Universe::out_of_memory_error_retry() { return out_of_memory_errors()->obj_at(_oom_retry); }
oop Universe::delayed_stack_overflow_error_message() { return _delayed_stack_overflow_error_message.resolve(); }
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.
objArrayOop preallocated_oom = out_of_memory_errors();
for (int i = 0; i < _oom_count; i++) {
if (throwable() == preallocated_oom->obj_at(i)) {
return false;
}
}
return true;
}
oop Universe::gen_out_of_memory_error(oop default_err) {
// generate an out of memory error:
// - if there is a preallocated error and stack traces are available
// (j.l.Throwable is initialized), then return the preallocated
// error with a filled in stack trace, and with the message
// provided by the default error.
// - otherwise, return the default error, without a stack trace.
int next;
if ((_preallocated_out_of_memory_error_avail_count > 0) &&
vmClasses::Throwable_klass()->is_initialized()) {
next = (int)Atomic::add(&_preallocated_out_of_memory_error_avail_count, -1);
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 {
JavaThread* current = JavaThread::current();
Handle default_err_h(current, default_err);
// get the error object at the slot and set set it to NULL so that the
// array isn't keeping it alive anymore.
Handle exc(current, 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_h());
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();
}
}
bool Universe::is_out_of_memory_error_metaspace(oop ex_obj) {
return java_lang_Throwable::message(ex_obj) == _msg_metaspace.resolve();
}
bool Universe::is_out_of_memory_error_class_metaspace(oop ex_obj) {
return java_lang_Throwable::message(ex_obj) == _msg_class_metaspace.resolve();
}
// Setup preallocated OutOfMemoryError errors
void Universe::create_preallocated_out_of_memory_errors(TRAPS) {
InstanceKlass* ik = vmClasses::OutOfMemoryError_klass();
objArrayOop oa = oopFactory::new_objArray(ik, _oom_count, CHECK);
objArrayHandle oom_array(THREAD, oa);
for (int i = 0; i < _oom_count; i++) {
oop oom_obj = ik->allocate_instance(CHECK);
oom_array->obj_at_put(i, oom_obj);
}
_out_of_memory_errors = OopHandle(vm_global(), oom_array());
Handle msg = java_lang_String::create_from_str("Java heap space", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_java_heap), msg());
msg = java_lang_String::create_from_str("C heap space", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_c_heap), msg());
msg = java_lang_String::create_from_str("Metaspace", CHECK);
_msg_metaspace = OopHandle(vm_global(), msg());
java_lang_Throwable::set_message(oom_array->obj_at(_oom_metaspace), msg());
msg = java_lang_String::create_from_str("Compressed class space", CHECK);
_msg_class_metaspace = OopHandle(vm_global(), msg());
java_lang_Throwable::set_message(oom_array->obj_at(_oom_class_metaspace), msg());
msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_array_size), msg());
msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_gc_overhead_limit), msg());
msg = java_lang_String::create_from_str("Java heap space: failed reallocation of scalar replaced objects", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_realloc_objects), msg());
msg = java_lang_String::create_from_str("Java heap space: failed retryable allocation", CHECK);
java_lang_Throwable::set_message(oom_array->obj_at(_oom_retry), msg());
// Setup the array of errors that have preallocated backtrace
int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
objArrayOop instance = oopFactory::new_objArray(ik, len, CHECK);
_preallocated_out_of_memory_error_array = OopHandle(vm_global(), instance);
objArrayHandle preallocated_oom_array(THREAD, instance);
for (int i=0; i<len; i++) {
oop err = ik->allocate_instance(CHECK);
Handle err_h(THREAD, err);
java_lang_Throwable::allocate_backtrace(err_h, CHECK);
preallocated_oom_array->obj_at_put(i, err_h());
}
_preallocated_out_of_memory_error_avail_count = (jint)len;
}
intptr_t Universe::_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;
}
bool Universe::contains_non_oop_word(void* p) {
return *(void**)p == non_oop_word();
}
static void initialize_global_behaviours() {
CompiledICProtectionBehaviour::set_current(new DefaultICProtectionBehaviour());
}
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", TRACETIME_LOG(Info, startuptime));
initialize_global_behaviours();
GCLogPrecious::initialize();
#ifdef _LP64
MetaspaceShared::adjust_heap_sizes_for_dumping();
#endif // _LP64
GCConfig::arguments()->initialize_heap_sizes();
jint status = Universe::initialize_heap();
if (status != JNI_OK) {
return status;
}
Universe::initialize_tlab();
Metaspace::global_initialize();
// Initialize performance counters for metaspaces
MetaspaceCounters::initialize_performance_counters();
// Checks 'AfterMemoryInit' constraints.
if (!JVMFlagLimit::check_all_constraints(JVMFlagConstraintPhase::AfterMemoryInit)) {
return JNI_EINVAL;
}
// Create memory for metadata. Must be after initializing heap for
// DumpSharedSpaces.
ClassLoaderData::init_null_class_loader_data();
// We have a heap so create the Method* caches before
// Metaspace::initialize_shared_spaces() tries to populate them.
Universe::_finalizer_register_cache = new LatestMethodCache();
Universe::_loader_addClass_cache = new LatestMethodCache();
Universe::_throw_illegal_access_error_cache = new LatestMethodCache();
Universe::_throw_no_such_method_error_cache = new LatestMethodCache();
Universe::_do_stack_walk_cache = new LatestMethodCache();
#if INCLUDE_CDS
DynamicArchive::check_for_dynamic_dump();
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.
MetaspaceShared::initialize_shared_spaces();
StringTable::create_table();
if (ArchiveHeapLoader::is_loaded()) {
StringTable::transfer_shared_strings_to_local_table();
}
} else
#endif
{
SymbolTable::create_table();
StringTable::create_table();
}
#if INCLUDE_CDS
if (Arguments::is_dumping_archive()) {
MetaspaceShared::prepare_for_dumping();
}
#endif
if (strlen(VerifySubSet) > 0) {
Universe::initialize_verify_flags();
}
ResolvedMethodTable::create_table();
return JNI_OK;
}
jint Universe::initialize_heap() {
assert(_collectedHeap == NULL, "Heap already created");
_collectedHeap = GCConfig::arguments()->create_heap();
log_info(gc)("Using %s", _collectedHeap->name());
return _collectedHeap->initialize();
}
void Universe::initialize_tlab() {
ThreadLocalAllocBuffer::set_max_size(Universe::heap()->max_tlab_size());
PLAB::startup_initialization();
if (UseTLAB) {
ThreadLocalAllocBuffer::startup_initialization();
}
}
ReservedHeapSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
assert(alignment <= Arguments::conservative_max_heap_alignment(),
"actual alignment " SIZE_FORMAT " must be within maximum heap alignment " SIZE_FORMAT,
alignment, Arguments::conservative_max_heap_alignment());
size_t total_reserved = align_up(heap_size, alignment);
assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
"heap size is too big for compressed oops");
size_t page_size = os::vm_page_size();
if (UseLargePages && is_aligned(alignment, os::large_page_size())) {
page_size = os::large_page_size();
} else {
// Parallel is the only collector that might opt out of using large pages
// for the heap.
assert(!UseLargePages || UseParallelGC , "Wrong alignment to use large pages");
}
// Now create the space.
ReservedHeapSpace total_rs(total_reserved, alignment, page_size, AllocateHeapAt);
if (total_rs.is_reserved()) {
assert((total_reserved == total_rs.size()) && ((uintptr_t)total_rs.base() % alignment == 0),
"must be exactly of required size and alignment");
// We are good.
if (AllocateHeapAt != NULL) {
log_info(gc,heap)("Successfully allocated Java heap at location %s", AllocateHeapAt);
}
if (UseCompressedOops) {
CompressedOops::initialize(total_rs);
}
Universe::calculate_verify_data((HeapWord*)total_rs.base(), (HeapWord*)total_rs.end());
return total_rs;
}
vm_exit_during_initialization(
err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap",
total_reserved/K));
// satisfy compiler
ShouldNotReachHere();
return ReservedHeapSpace(0, 0, os::vm_page_size());
}
OopStorage* Universe::vm_weak() {
return Universe::_vm_weak;
}
OopStorage* Universe::vm_global() {
return Universe::_vm_global;
}
void Universe::oopstorage_init() {
Universe::_vm_global = OopStorageSet::create_strong("VM Global", mtInternal);
Universe::_vm_weak = OopStorageSet::create_weak("VM Weak", mtInternal);
}
void universe_oopstorage_init() {
Universe::oopstorage_init();
}
void initialize_known_method(LatestMethodCache* method_cache,
InstanceKlass* ik,
const char* method,
Symbol* signature,
bool is_static, TRAPS)
{
TempNewSymbol name = SymbolTable::new_symbol(method);
Method* m = NULL;
// The klass must be linked before looking up the method.
if (!ik->link_class_or_fail(THREAD) ||
((m = ik->find_method(name, signature)) == NULL) ||
is_static != m->is_static()) {
ResourceMark rm(THREAD);
// NoSuchMethodException doesn't actually work because it tries to run the
// <init> function before java_lang_Class is linked. Print error and exit.
vm_exit_during_initialization(err_msg("Unable to link/verify %s.%s method",
ik->name()->as_C_string(), method));
}
method_cache->init(ik, m);
}
void Universe::initialize_known_methods(TRAPS) {
// Set up static method for registering finalizers
initialize_known_method(_finalizer_register_cache,
vmClasses::Finalizer_klass(),
"register",
vmSymbols::object_void_signature(), true, CHECK);
initialize_known_method(_throw_illegal_access_error_cache,
vmClasses::internal_Unsafe_klass(),
"throwIllegalAccessError",
vmSymbols::void_method_signature(), true, CHECK);
initialize_known_method(_throw_no_such_method_error_cache,
vmClasses::internal_Unsafe_klass(),
"throwNoSuchMethodError",
vmSymbols::void_method_signature(), true, CHECK);
// Set up method for registering loaded classes in class loader vector
initialize_known_method(_loader_addClass_cache,
vmClasses::ClassLoader_klass(),
"addClass",
vmSymbols::class_void_signature(), false, CHECK);
// Set up method for stack walking
initialize_known_method(_do_stack_walk_cache,
vmClasses::AbstractStackWalker_klass(),
"doStackWalk",
vmSymbols::doStackWalk_signature(), false, CHECK);
}
void universe2_init() {
EXCEPTION_MARK;
Universe::genesis(CATCH);
}
// Set after initialization of the module runtime, call_initModuleRuntime
void universe_post_module_init() {
Universe::_module_initialized = true;
}
bool universe_post_init() {
assert(!is_init_completed(), "Error: initialization not yet completed!");
Universe::_fully_initialized = true;
EXCEPTION_MARK;
if (!UseSharedSpaces) {
reinitialize_vtables();
reinitialize_itables();
}
HandleMark hm(THREAD);
// Setup preallocated empty java.lang.Class array for Method reflection.
objArrayOop the_empty_class_array = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_false);
Universe::_the_empty_class_array = OopHandle(Universe::vm_global(), the_empty_class_array);
// Setup preallocated OutOfMemoryError errors
Universe::create_preallocated_out_of_memory_errors(CHECK_false);
oop instance;
// Setup preallocated cause message for delayed StackOverflowError
if (StackReservedPages > 0) {
instance = java_lang_String::create_oop_from_str("Delayed StackOverflowError due to ReservedStackAccess annotated method", CHECK_false);
Universe::_delayed_stack_overflow_error_message = OopHandle(Universe::vm_global(), instance);
}
// Setup preallocated NullPointerException
// (this is currently used for a cheap & dirty solution in compiler exception handling)
Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
Universe::_null_ptr_exception_instance = OopHandle(Universe::vm_global(), instance);
// Setup preallocated ArithmeticException
// (this is currently used for a cheap & dirty solution in compiler exception handling)
k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
Universe::_arithmetic_exception_instance = OopHandle(Universe::vm_global(), instance);
// Virtual Machine Error for when we get into a situation we can't resolve
k = vmClasses::VirtualMachineError_klass();
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
}
instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
Universe::_virtual_machine_error_instance = OopHandle(Universe::vm_global(), instance);
Handle msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
java_lang_Throwable::set_message(Universe::arithmetic_exception_instance(), msg());
Universe::initialize_known_methods(CHECK_false);
// This needs to be done before the first scavenge/gc, since
// it's an input to soft ref clearing policy.
{
MutexLocker x(THREAD, Heap_lock);
Universe::heap()->update_capacity_and_used_at_gc();
}
// ("weak") refs processing infrastructure initialization
Universe::heap()->post_initialize();
MemoryService::add_metaspace_memory_pools();
MemoryService::set_universe_heap(Universe::heap());
#if INCLUDE_CDS
MetaspaceShared::post_initialize(CHECK_false);
#endif
return true;
}
void Universe::compute_base_vtable_size() {
_base_vtable_size = ClassLoader::compute_Object_vtable();
}
void Universe::print_on(outputStream* st) {
GCMutexLocker hl(Heap_lock); // Heap_lock might be locked by caller thread.
st->print_cr("Heap");
heap()->print_on(st);
}
void Universe::print_heap_at_SIGBREAK() {
if (PrintHeapAtSIGBREAK) {
print_on(tty);
tty->cr();
tty->flush();
}
}
void Universe::initialize_verify_flags() {
verify_flags = 0;
const char delimiter[] = " ,";
size_t length = strlen(VerifySubSet);
char* subset_list = NEW_C_HEAP_ARRAY(char, length + 1, mtInternal);
strncpy(subset_list, VerifySubSet, length + 1);
char* save_ptr;
char* token = strtok_r(subset_list, delimiter, &save_ptr);
while (token != NULL) {
if (strcmp(token, "threads") == 0) {
verify_flags |= Verify_Threads;
} else if (strcmp(token, "heap") == 0) {
verify_flags |= Verify_Heap;
} else if (strcmp(token, "symbol_table") == 0) {
verify_flags |= Verify_SymbolTable;
} else if (strcmp(token, "string_table") == 0) {
verify_flags |= Verify_StringTable;
} else if (strcmp(token, "codecache") == 0) {
verify_flags |= Verify_CodeCache;
} else if (strcmp(token, "dictionary") == 0) {
verify_flags |= Verify_SystemDictionary;
} else if (strcmp(token, "classloader_data_graph") == 0) {
verify_flags |= Verify_ClassLoaderDataGraph;
} else if (strcmp(token, "metaspace") == 0) {
verify_flags |= Verify_MetaspaceUtils;
} else if (strcmp(token, "jni_handles") == 0) {
verify_flags |= Verify_JNIHandles;
} else if (strcmp(token, "codecache_oops") == 0) {
verify_flags |= Verify_CodeCacheOops;
} else if (strcmp(token, "resolved_method_table") == 0) {
verify_flags |= Verify_ResolvedMethodTable;
} else if (strcmp(token, "stringdedup") == 0) {
verify_flags |= Verify_StringDedup;
} else {
vm_exit_during_initialization(err_msg("VerifySubSet: \'%s\' memory sub-system is unknown, please correct it", token));
}
token = strtok_r(NULL, delimiter, &save_ptr);
}
FREE_C_HEAP_ARRAY(char, subset_list);
}
bool Universe::should_verify_subset(uint subset) {
if (verify_flags & subset) {
return true;
}
return false;
}
void Universe::verify(VerifyOption option, const char* prefix) {
COMPILER2_PRESENT(
assert(!DerivedPointerTable::is_active(),
"DPT should not be active during verification "
"(of thread stacks below)");
)
Thread* thread = Thread::current();
ResourceMark rm(thread);
HandleMark hm(thread); // Handles created during verification can be zapped
_verify_count++;
FormatBuffer<> title("Verifying %s", prefix);
GCTraceTime(Info, gc, verify) tm(title.buffer());
if (should_verify_subset(Verify_Threads)) {
log_debug(gc, verify)("Threads");
Threads::verify();
}
if (should_verify_subset(Verify_Heap)) {
log_debug(gc, verify)("Heap");
heap()->verify(option);
}
if (should_verify_subset(Verify_SymbolTable)) {
log_debug(gc, verify)("SymbolTable");
SymbolTable::verify();
}
if (should_verify_subset(Verify_StringTable)) {
log_debug(gc, verify)("StringTable");
StringTable::verify();
}
if (should_verify_subset(Verify_CodeCache)) {
log_debug(gc, verify)("CodeCache");
CodeCache::verify();
}
if (should_verify_subset(Verify_SystemDictionary)) {
log_debug(gc, verify)("SystemDictionary");
SystemDictionary::verify();
}
if (should_verify_subset(Verify_ClassLoaderDataGraph)) {
log_debug(gc, verify)("ClassLoaderDataGraph");
ClassLoaderDataGraph::verify();
}
if (should_verify_subset(Verify_MetaspaceUtils)) {
log_debug(gc, verify)("MetaspaceUtils");
DEBUG_ONLY(MetaspaceUtils::verify();)
}
if (should_verify_subset(Verify_JNIHandles)) {
log_debug(gc, verify)("JNIHandles");
JNIHandles::verify();
}
if (should_verify_subset(Verify_CodeCacheOops)) {
log_debug(gc, verify)("CodeCache Oops");
CodeCache::verify_oops();
}
if (should_verify_subset(Verify_ResolvedMethodTable)) {
log_debug(gc, verify)("ResolvedMethodTable Oops");
ResolvedMethodTable::verify();
}
if (should_verify_subset(Verify_StringDedup)) {
log_debug(gc, verify)("String Deduplication");
StringDedup::verify();
}
}
#ifndef PRODUCT
void Universe::calculate_verify_data(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 = CollectedHeap::min_fill_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_oop_mask == 0 && _verify_oop_bits == (uintptr_t)-1)) {
assert(_verify_oop_mask == mask && _verify_oop_bits == bits, "mask stability");
}
_verify_oop_mask = mask;
_verify_oop_bits = bits;
}
// Oop verification (see MacroAssembler::verify_oop)
uintptr_t Universe::verify_oop_mask() {
return _verify_oop_mask;
}
uintptr_t Universe::verify_oop_bits() {
return _verify_oop_bits;
}
uintptr_t Universe::verify_mark_mask() {
return markWord::lock_mask_in_place;
}
uintptr_t Universe::verify_mark_bits() {
intptr_t mask = verify_mark_mask();
intptr_t bits = (intptr_t)markWord::prototype().value();
assert((bits & ~mask) == 0, "no stray header bits");
return bits;
}
#endif // PRODUCT
void LatestMethodCache::init(Klass* k, Method* m) {
if (!UseSharedSpaces) {
_klass = k;
}
#ifndef PRODUCT
else {
// sharing initialization should have already set up _klass
assert(_klass != NULL, "just checking");
}
#endif
_method_idnum = m->method_idnum();
assert(_method_idnum >= 0, "sanity check");
}
Method* LatestMethodCache::get_method() {
if (klass() == NULL) return NULL;
InstanceKlass* ik = InstanceKlass::cast(klass());
Method* 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);
objArrayOop fullgc_alot_dummy_array = (objArrayOop)_fullgc_alot_dummy_array.resolve();
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.release(Universe::vm_global());
_fullgc_alot_dummy_array = OopHandle(); // NULL out OopStorage pointer.
return false;
}
// Release dummy at bottom of old generation
fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
}
return true;
}
bool Universe::is_gc_active() {
return heap()->is_gc_active();
}
bool Universe::is_in_heap(const void* p) {
return heap()->is_in(p);
}
#endif // ASSERT
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