/* * Copyright (c) 2018, 2025, 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 "cds/aotArtifactFinder.hpp" #include "cds/aotClassInitializer.hpp" #include "cds/aotClassLocation.hpp" #include "cds/aotLogging.hpp" #include "cds/aotReferenceObjSupport.hpp" #include "cds/archiveBuilder.hpp" #include "cds/archiveHeapLoader.hpp" #include "cds/archiveHeapWriter.hpp" #include "cds/archiveUtils.hpp" #include "cds/cdsConfig.hpp" #include "cds/cdsEnumKlass.hpp" #include "cds/cdsHeapVerifier.hpp" #include "cds/heapShared.hpp" #include "cds/metaspaceShared.hpp" #include "classfile/classLoaderData.hpp" #include "classfile/classLoaderExt.hpp" #include "classfile/javaClasses.inline.hpp" #include "classfile/modules.hpp" #include "classfile/stringTable.hpp" #include "classfile/symbolTable.hpp" #include "classfile/systemDictionary.hpp" #include "classfile/systemDictionaryShared.hpp" #include "classfile/vmClasses.hpp" #include "classfile/vmSymbols.hpp" #include "gc/shared/collectedHeap.hpp" #include "gc/shared/gcLocker.hpp" #include "gc/shared/gcVMOperations.hpp" #include "logging/log.hpp" #include "logging/logStream.hpp" #include "memory/iterator.inline.hpp" #include "memory/resourceArea.hpp" #include "memory/universe.hpp" #include "oops/compressedOops.inline.hpp" #include "oops/fieldStreams.inline.hpp" #include "oops/objArrayOop.inline.hpp" #include "oops/oop.inline.hpp" #include "oops/typeArrayOop.inline.hpp" #include "prims/jvmtiExport.hpp" #include "runtime/arguments.hpp" #include "runtime/fieldDescriptor.inline.hpp" #include "runtime/init.hpp" #include "runtime/javaCalls.hpp" #include "runtime/mutexLocker.hpp" #include "runtime/safepointVerifiers.hpp" #include "utilities/bitMap.inline.hpp" #include "utilities/copy.hpp" #if INCLUDE_G1GC #include "gc/g1/g1CollectedHeap.hpp" #endif #if INCLUDE_CDS_JAVA_HEAP struct ArchivableStaticFieldInfo { const char* klass_name; const char* field_name; InstanceKlass* klass; int offset; BasicType type; ArchivableStaticFieldInfo(const char* k, const char* f) : klass_name(k), field_name(f), klass(nullptr), offset(0), type(T_ILLEGAL) {} bool valid() { return klass_name != nullptr; } }; DumpedInternedStrings *HeapShared::_dumped_interned_strings = nullptr; size_t HeapShared::_alloc_count[HeapShared::ALLOC_STAT_SLOTS]; size_t HeapShared::_alloc_size[HeapShared::ALLOC_STAT_SLOTS]; size_t HeapShared::_total_obj_count; size_t HeapShared::_total_obj_size; #ifndef PRODUCT #define ARCHIVE_TEST_FIELD_NAME "archivedObjects" static Array* _archived_ArchiveHeapTestClass = nullptr; static const char* _test_class_name = nullptr; static Klass* _test_class = nullptr; static const ArchivedKlassSubGraphInfoRecord* _test_class_record = nullptr; #endif // // If you add new entries to the following tables, you should know what you're doing! // static ArchivableStaticFieldInfo archive_subgraph_entry_fields[] = { {"java/lang/Integer$IntegerCache", "archivedCache"}, {"java/lang/Long$LongCache", "archivedCache"}, {"java/lang/Byte$ByteCache", "archivedCache"}, {"java/lang/Short$ShortCache", "archivedCache"}, {"java/lang/Character$CharacterCache", "archivedCache"}, {"java/util/jar/Attributes$Name", "KNOWN_NAMES"}, {"sun/util/locale/BaseLocale", "constantBaseLocales"}, {"jdk/internal/module/ArchivedModuleGraph", "archivedModuleGraph"}, {"java/util/ImmutableCollections", "archivedObjects"}, {"java/lang/ModuleLayer", "EMPTY_LAYER"}, {"java/lang/module/Configuration", "EMPTY_CONFIGURATION"}, {"jdk/internal/math/FDBigInteger", "archivedCaches"}, #ifndef PRODUCT {nullptr, nullptr}, // Extra slot for -XX:ArchiveHeapTestClass #endif {nullptr, nullptr}, }; // full module graph static ArchivableStaticFieldInfo fmg_archive_subgraph_entry_fields[] = { {"jdk/internal/loader/ArchivedClassLoaders", "archivedClassLoaders"}, {ARCHIVED_BOOT_LAYER_CLASS, ARCHIVED_BOOT_LAYER_FIELD}, {"java/lang/Module$ArchivedData", "archivedData"}, {nullptr, nullptr}, }; KlassSubGraphInfo* HeapShared::_dump_time_special_subgraph; ArchivedKlassSubGraphInfoRecord* HeapShared::_run_time_special_subgraph; GrowableArrayCHeap* HeapShared::_pending_roots = nullptr; GrowableArrayCHeap* HeapShared::_root_segments = nullptr; int HeapShared::_root_segment_max_size_elems; OopHandle HeapShared::_scratch_basic_type_mirrors[T_VOID+1]; MetaspaceObjToOopHandleTable* HeapShared::_scratch_objects_table = nullptr; static bool is_subgraph_root_class_of(ArchivableStaticFieldInfo fields[], InstanceKlass* ik) { for (int i = 0; fields[i].valid(); i++) { if (fields[i].klass == ik) { return true; } } return false; } bool HeapShared::is_subgraph_root_class(InstanceKlass* ik) { return is_subgraph_root_class_of(archive_subgraph_entry_fields, ik) || is_subgraph_root_class_of(fmg_archive_subgraph_entry_fields, ik); } unsigned HeapShared::oop_hash(oop const& p) { // Do not call p->identity_hash() as that will update the // object header. return primitive_hash(cast_from_oop(p)); } static void reset_states(oop obj, TRAPS) { Handle h_obj(THREAD, obj); InstanceKlass* klass = InstanceKlass::cast(obj->klass()); TempNewSymbol method_name = SymbolTable::new_symbol("resetArchivedStates"); Symbol* method_sig = vmSymbols::void_method_signature(); while (klass != nullptr) { Method* method = klass->find_method(method_name, method_sig); if (method != nullptr) { assert(method->is_private(), "must be"); if (log_is_enabled(Debug, aot)) { ResourceMark rm(THREAD); log_debug(aot)(" calling %s", method->name_and_sig_as_C_string()); } JavaValue result(T_VOID); JavaCalls::call_special(&result, h_obj, klass, method_name, method_sig, CHECK); } klass = klass->java_super(); } } void HeapShared::reset_archived_object_states(TRAPS) { assert(CDSConfig::is_dumping_heap(), "dump-time only"); log_debug(aot)("Resetting platform loader"); reset_states(SystemDictionary::java_platform_loader(), CHECK); log_debug(aot)("Resetting system loader"); reset_states(SystemDictionary::java_system_loader(), CHECK); // Clean up jdk.internal.loader.ClassLoaders::bootLoader(), which is not // directly used for class loading, but rather is used by the core library // to keep track of resources, etc, loaded by the null class loader. // // Note, this object is non-null, and is not the same as // ClassLoaderData::the_null_class_loader_data()->class_loader(), // which is null. log_debug(aot)("Resetting boot loader"); JavaValue result(T_OBJECT); JavaCalls::call_static(&result, vmClasses::jdk_internal_loader_ClassLoaders_klass(), vmSymbols::bootLoader_name(), vmSymbols::void_BuiltinClassLoader_signature(), CHECK); Handle boot_loader(THREAD, result.get_oop()); reset_states(boot_loader(), CHECK); } HeapShared::ArchivedObjectCache* HeapShared::_archived_object_cache = nullptr; bool HeapShared::has_been_archived(oop obj) { assert(CDSConfig::is_dumping_heap(), "dump-time only"); return archived_object_cache()->get(obj) != nullptr; } int HeapShared::append_root(oop obj) { assert(CDSConfig::is_dumping_heap(), "dump-time only"); if (obj != nullptr) { assert(has_been_archived(obj), "must be"); } // No GC should happen since we aren't scanning _pending_roots. assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); return _pending_roots->append(obj); } objArrayOop HeapShared::root_segment(int segment_idx) { if (CDSConfig::is_dumping_heap()) { assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread"); } else { assert(CDSConfig::is_using_archive(), "must be"); } objArrayOop segment = (objArrayOop)_root_segments->at(segment_idx).resolve(); assert(segment != nullptr, "should have been initialized"); return segment; } void HeapShared::get_segment_indexes(int idx, int& seg_idx, int& int_idx) { assert(_root_segment_max_size_elems > 0, "sanity"); // Try to avoid divisions for the common case. if (idx < _root_segment_max_size_elems) { seg_idx = 0; int_idx = idx; } else { seg_idx = idx / _root_segment_max_size_elems; int_idx = idx % _root_segment_max_size_elems; } assert(idx == seg_idx * _root_segment_max_size_elems + int_idx, "sanity: %d index maps to %d segment and %d internal", idx, seg_idx, int_idx); } // Returns an objArray that contains all the roots of the archived objects oop HeapShared::get_root(int index, bool clear) { assert(index >= 0, "sanity"); assert(!CDSConfig::is_dumping_heap() && CDSConfig::is_using_archive(), "runtime only"); assert(!_root_segments->is_empty(), "must have loaded shared heap"); int seg_idx, int_idx; get_segment_indexes(index, seg_idx, int_idx); oop result = root_segment(seg_idx)->obj_at(int_idx); if (clear) { clear_root(index); } return result; } void HeapShared::clear_root(int index) { assert(index >= 0, "sanity"); assert(CDSConfig::is_using_archive(), "must be"); if (ArchiveHeapLoader::is_in_use()) { int seg_idx, int_idx; get_segment_indexes(index, seg_idx, int_idx); if (log_is_enabled(Debug, aot, heap)) { oop old = root_segment(seg_idx)->obj_at(int_idx); log_debug(aot, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old)); } root_segment(seg_idx)->obj_at_put(int_idx, nullptr); } } bool HeapShared::archive_object(oop obj, oop referrer, KlassSubGraphInfo* subgraph_info) { assert(CDSConfig::is_dumping_heap(), "dump-time only"); assert(!obj->is_stackChunk(), "do not archive stack chunks"); if (has_been_archived(obj)) { return true; } if (ArchiveHeapWriter::is_too_large_to_archive(obj->size())) { log_debug(aot, heap)("Cannot archive, object (" PTR_FORMAT ") is too large: %zu", p2i(obj), obj->size()); debug_trace(); return false; } else { count_allocation(obj->size()); ArchiveHeapWriter::add_source_obj(obj); CachedOopInfo info = make_cached_oop_info(obj, referrer); archived_object_cache()->put_when_absent(obj, info); archived_object_cache()->maybe_grow(); mark_native_pointers(obj); Klass* k = obj->klass(); if (k->is_instance_klass()) { // Whenever we see a non-array Java object of type X, we mark X to be aot-initialized. // This ensures that during the production run, whenever Java code sees a cached object // of type X, we know that X is already initialized. (see TODO comment below ...) if (InstanceKlass::cast(k)->is_enum_subclass() // We can't rerun of enum classes (see cdsEnumKlass.cpp) so // we must store them as AOT-initialized. || (subgraph_info == _dump_time_special_subgraph)) // TODO: we do this only for the special subgraph for now. Extending this to // other subgraphs would require more refactoring of the core library (such as // move some initialization logic into runtimeSetup()). // // For the other subgraphs, we have a weaker mechanism to ensure that // all classes in a subgraph are initialized before the subgraph is programmatically // returned from jdk.internal.misc.CDS::initializeFromArchive(). // See HeapShared::initialize_from_archived_subgraph(). { AOTArtifactFinder::add_aot_inited_class(InstanceKlass::cast(k)); } if (java_lang_Class::is_instance(obj)) { Klass* mirror_k = java_lang_Class::as_Klass(obj); if (mirror_k != nullptr) { AOTArtifactFinder::add_cached_class(mirror_k); } } else if (java_lang_invoke_ResolvedMethodName::is_instance(obj)) { Method* m = java_lang_invoke_ResolvedMethodName::vmtarget(obj); if (m != nullptr) { InstanceKlass* method_holder = m->method_holder(); AOTArtifactFinder::add_cached_class(method_holder); } } } if (log_is_enabled(Debug, aot, heap)) { ResourceMark rm; LogTarget(Debug, aot, heap) log; LogStream out(log); out.print("Archived heap object " PTR_FORMAT " : %s ", p2i(obj), obj->klass()->external_name()); if (java_lang_Class::is_instance(obj)) { Klass* k = java_lang_Class::as_Klass(obj); if (k != nullptr) { out.print("%s", k->external_name()); } else { out.print("primitive"); } } out.cr(); } return true; } } class MetaspaceObjToOopHandleTable: public ResourceHashtable { public: oop get_oop(MetaspaceObj* ptr) { MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); OopHandle* handle = get(ptr); if (handle != nullptr) { return handle->resolve(); } else { return nullptr; } } void set_oop(MetaspaceObj* ptr, oop o) { MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); OopHandle handle(Universe::vm_global(), o); bool is_new = put(ptr, handle); assert(is_new, "cannot set twice"); } void remove_oop(MetaspaceObj* ptr) { MutexLocker ml(ScratchObjects_lock, Mutex::_no_safepoint_check_flag); OopHandle* handle = get(ptr); if (handle != nullptr) { handle->release(Universe::vm_global()); remove(ptr); } } }; void HeapShared::add_scratch_resolved_references(ConstantPool* src, objArrayOop dest) { if (SystemDictionaryShared::is_builtin_loader(src->pool_holder()->class_loader_data())) { _scratch_objects_table->set_oop(src, dest); } } objArrayOop HeapShared::scratch_resolved_references(ConstantPool* src) { return (objArrayOop)_scratch_objects_table->get_oop(src); } void HeapShared::init_dumping() { _scratch_objects_table = new (mtClass)MetaspaceObjToOopHandleTable(); _pending_roots = new GrowableArrayCHeap(500); } void HeapShared::init_scratch_objects_for_basic_type_mirrors(TRAPS) { 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); _scratch_basic_type_mirrors[i] = OopHandle(Universe::vm_global(), m); } } } // Given java_mirror that represents a (primitive or reference) type T, // return the "scratch" version that represents the same type T. // Note that if java_mirror will be returned if it's already a // scratch mirror. // // See java_lang_Class::create_scratch_mirror() for more info. oop HeapShared::scratch_java_mirror(oop java_mirror) { assert(java_lang_Class::is_instance(java_mirror), "must be"); for (int i = T_BOOLEAN; i < T_VOID+1; i++) { BasicType bt = (BasicType)i; if (!is_reference_type(bt)) { if (_scratch_basic_type_mirrors[i].resolve() == java_mirror) { return java_mirror; } } } if (java_lang_Class::is_primitive(java_mirror)) { return scratch_java_mirror(java_lang_Class::as_BasicType(java_mirror)); } else { return scratch_java_mirror(java_lang_Class::as_Klass(java_mirror)); } } oop HeapShared::scratch_java_mirror(BasicType t) { assert((uint)t < T_VOID+1, "range check"); assert(!is_reference_type(t), "sanity"); return _scratch_basic_type_mirrors[t].resolve(); } oop HeapShared::scratch_java_mirror(Klass* k) { return _scratch_objects_table->get_oop(k); } void HeapShared::set_scratch_java_mirror(Klass* k, oop mirror) { _scratch_objects_table->set_oop(k, mirror); } void HeapShared::remove_scratch_objects(Klass* k) { // Klass is being deallocated. Java mirror can still be alive, and it should not // point to dead klass. We need to break the link from mirror to the Klass. // See how InstanceKlass::deallocate_contents does it for normal mirrors. oop mirror = _scratch_objects_table->get_oop(k); if (mirror != nullptr) { java_lang_Class::set_klass(mirror, nullptr); } _scratch_objects_table->remove_oop(k); if (k->is_instance_klass()) { _scratch_objects_table->remove(InstanceKlass::cast(k)->constants()); } } //TODO: we eventually want a more direct test for these kinds of things. //For example the JVM could record some bit of context from the creation //of the klass, such as who called the hidden class factory. Using //string compares on names is fragile and will break as soon as somebody //changes the names in the JDK code. See discussion in JDK-8342481 for //related ideas about marking AOT-related classes. bool HeapShared::is_lambda_form_klass(InstanceKlass* ik) { return ik->is_hidden() && (ik->name()->starts_with("java/lang/invoke/LambdaForm$MH+") || ik->name()->starts_with("java/lang/invoke/LambdaForm$DMH+") || ik->name()->starts_with("java/lang/invoke/LambdaForm$BMH+") || ik->name()->starts_with("java/lang/invoke/LambdaForm$VH+")); } bool HeapShared::is_lambda_proxy_klass(InstanceKlass* ik) { return ik->is_hidden() && (ik->name()->index_of_at(0, "$$Lambda+", 9) > 0); } bool HeapShared::is_string_concat_klass(InstanceKlass* ik) { return ik->is_hidden() && ik->name()->starts_with("java/lang/String$$StringConcat"); } bool HeapShared::is_archivable_hidden_klass(InstanceKlass* ik) { return CDSConfig::is_dumping_method_handles() && (is_lambda_form_klass(ik) || is_lambda_proxy_klass(ik) || is_string_concat_klass(ik)); } void HeapShared::copy_and_rescan_aot_inited_mirror(InstanceKlass* ik) { ik->set_has_aot_initialized_mirror(); if (AOTClassInitializer::is_runtime_setup_required(ik)) { ik->set_is_runtime_setup_required(); } oop orig_mirror = ik->java_mirror(); oop m = scratch_java_mirror(ik); assert(ik->is_initialized(), "must be"); int nfields = 0; for (JavaFieldStream fs(ik); !fs.done(); fs.next()) { if (fs.access_flags().is_static()) { fieldDescriptor& fd = fs.field_descriptor(); int offset = fd.offset(); switch (fd.field_type()) { case T_OBJECT: case T_ARRAY: { oop field_obj = orig_mirror->obj_field(offset); if (offset == java_lang_Class::reflection_data_offset()) { // Class::reflectData use SoftReference, which cannot be archived. Set it // to null and it will be recreated at runtime. field_obj = nullptr; } m->obj_field_put(offset, field_obj); if (field_obj != nullptr) { bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, field_obj); assert(success, "sanity"); } } break; case T_BOOLEAN: m->bool_field_put(offset, orig_mirror->bool_field(offset)); break; case T_BYTE: m->byte_field_put(offset, orig_mirror->byte_field(offset)); break; case T_SHORT: m->short_field_put(offset, orig_mirror->short_field(offset)); break; case T_CHAR: m->char_field_put(offset, orig_mirror->char_field(offset)); break; case T_INT: m->int_field_put(offset, orig_mirror->int_field(offset)); break; case T_LONG: m->long_field_put(offset, orig_mirror->long_field(offset)); break; case T_FLOAT: m->float_field_put(offset, orig_mirror->float_field(offset)); break; case T_DOUBLE: m->double_field_put(offset, orig_mirror->double_field(offset)); break; default: ShouldNotReachHere(); } nfields ++; } } oop class_data = java_lang_Class::class_data(orig_mirror); java_lang_Class::set_class_data(m, class_data); if (class_data != nullptr) { bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, class_data); assert(success, "sanity"); } if (log_is_enabled(Debug, aot, init)) { ResourceMark rm; log_debug(aot, init)("copied %3d field(s) in aot-initialized mirror %s%s%s", nfields, ik->external_name(), ik->is_hidden() ? " (hidden)" : "", ik->is_enum_subclass() ? " (enum)" : ""); } } static void copy_java_mirror_hashcode(oop orig_mirror, oop scratch_m) { // We need to retain the identity_hash, because it may have been used by some hashtables // in the shared heap. if (!orig_mirror->fast_no_hash_check()) { intptr_t src_hash = orig_mirror->identity_hash(); if (UseCompactObjectHeaders) { narrowKlass nk = CompressedKlassPointers::encode(orig_mirror->klass()); scratch_m->set_mark(markWord::prototype().set_narrow_klass(nk).copy_set_hash(src_hash)); } else { scratch_m->set_mark(markWord::prototype().copy_set_hash(src_hash)); } assert(scratch_m->mark().is_unlocked(), "sanity"); DEBUG_ONLY(intptr_t archived_hash = scratch_m->identity_hash()); assert(src_hash == archived_hash, "Different hash codes: original " INTPTR_FORMAT ", archived " INTPTR_FORMAT, src_hash, archived_hash); } } static objArrayOop get_archived_resolved_references(InstanceKlass* src_ik) { if (SystemDictionaryShared::is_builtin_loader(src_ik->class_loader_data())) { objArrayOop rr = src_ik->constants()->resolved_references_or_null(); if (rr != nullptr && !ArchiveHeapWriter::is_too_large_to_archive(rr)) { return HeapShared::scratch_resolved_references(src_ik->constants()); } } return nullptr; } void HeapShared::archive_strings() { oop shared_strings_array = StringTable::init_shared_strings_array(); bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, shared_strings_array); assert(success, "shared strings array must not point to arrays or strings that are too large to archive"); StringTable::set_shared_strings_array_index(append_root(shared_strings_array)); } int HeapShared::archive_exception_instance(oop exception) { bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, exception); assert(success, "sanity"); return append_root(exception); } void HeapShared::mark_native_pointers(oop orig_obj) { if (java_lang_Class::is_instance(orig_obj)) { ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::klass_offset()); ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_Class::array_klass_offset()); } else if (java_lang_invoke_ResolvedMethodName::is_instance(orig_obj)) { ArchiveHeapWriter::mark_native_pointer(orig_obj, java_lang_invoke_ResolvedMethodName::vmtarget_offset()); } } void HeapShared::get_pointer_info(oop src_obj, bool& has_oop_pointers, bool& has_native_pointers) { CachedOopInfo* info = archived_object_cache()->get(src_obj); assert(info != nullptr, "must be"); has_oop_pointers = info->has_oop_pointers(); has_native_pointers = info->has_native_pointers(); } void HeapShared::set_has_native_pointers(oop src_obj) { CachedOopInfo* info = archived_object_cache()->get(src_obj); assert(info != nullptr, "must be"); info->set_has_native_pointers(); } // Between start_scanning_for_oops() and end_scanning_for_oops(), we discover all Java heap objects that // should be stored in the AOT cache. The scanning is coordinated by AOTArtifactFinder. void HeapShared::start_scanning_for_oops() { { NoSafepointVerifier nsv; // The special subgraph doesn't belong to any class. We use Object_klass() here just // for convenience. _dump_time_special_subgraph = init_subgraph_info(vmClasses::Object_klass(), false); // Cache for recording where the archived objects are copied to create_archived_object_cache(); if (UseCompressedOops || UseG1GC) { aot_log_info(aot)("Heap range = [" PTR_FORMAT " - " PTR_FORMAT "]", UseCompressedOops ? p2i(CompressedOops::begin()) : p2i((address)G1CollectedHeap::heap()->reserved().start()), UseCompressedOops ? p2i(CompressedOops::end()) : p2i((address)G1CollectedHeap::heap()->reserved().end())); } archive_subgraphs(); } init_seen_objects_table(); Universe::archive_exception_instances(); } void HeapShared::end_scanning_for_oops() { archive_strings(); delete_seen_objects_table(); } void HeapShared::write_heap(ArchiveHeapInfo *heap_info) { { NoSafepointVerifier nsv; CDSHeapVerifier::verify(); check_special_subgraph_classes(); } StringTable::write_shared_table(); ArchiveHeapWriter::write(_pending_roots, heap_info); ArchiveBuilder::OtherROAllocMark mark; write_subgraph_info_table(); } void HeapShared::scan_java_mirror(oop orig_mirror) { oop m = scratch_java_mirror(orig_mirror); if (m != nullptr) { // nullptr if for custom class loader copy_java_mirror_hashcode(orig_mirror, m); bool success = archive_reachable_objects_from(1, _dump_time_special_subgraph, m); assert(success, "sanity"); } } void HeapShared::scan_java_class(Klass* orig_k) { scan_java_mirror(orig_k->java_mirror()); if (orig_k->is_instance_klass()) { InstanceKlass* orig_ik = InstanceKlass::cast(orig_k); orig_ik->constants()->prepare_resolved_references_for_archiving(); objArrayOop rr = get_archived_resolved_references(orig_ik); if (rr != nullptr) { bool success = HeapShared::archive_reachable_objects_from(1, _dump_time_special_subgraph, rr); assert(success, "must be"); } } } void HeapShared::archive_subgraphs() { assert(CDSConfig::is_dumping_heap(), "must be"); archive_object_subgraphs(archive_subgraph_entry_fields, false /* is_full_module_graph */); if (CDSConfig::is_dumping_full_module_graph()) { archive_object_subgraphs(fmg_archive_subgraph_entry_fields, true /* is_full_module_graph */); Modules::verify_archived_modules(); } } // // Subgraph archiving support // HeapShared::DumpTimeKlassSubGraphInfoTable* HeapShared::_dump_time_subgraph_info_table = nullptr; HeapShared::RunTimeKlassSubGraphInfoTable HeapShared::_run_time_subgraph_info_table; // Get the subgraph_info for Klass k. A new subgraph_info is created if // there is no existing one for k. The subgraph_info records the "buffered" // address of the class. KlassSubGraphInfo* HeapShared::init_subgraph_info(Klass* k, bool is_full_module_graph) { assert(CDSConfig::is_dumping_heap(), "dump time only"); bool created; KlassSubGraphInfo* info = _dump_time_subgraph_info_table->put_if_absent(k, KlassSubGraphInfo(k, is_full_module_graph), &created); assert(created, "must not initialize twice"); return info; } KlassSubGraphInfo* HeapShared::get_subgraph_info(Klass* k) { assert(CDSConfig::is_dumping_heap(), "dump time only"); KlassSubGraphInfo* info = _dump_time_subgraph_info_table->get(k); assert(info != nullptr, "must have been initialized"); return info; } // Add an entry field to the current KlassSubGraphInfo. void KlassSubGraphInfo::add_subgraph_entry_field(int static_field_offset, oop v) { assert(CDSConfig::is_dumping_heap(), "dump time only"); if (_subgraph_entry_fields == nullptr) { _subgraph_entry_fields = new (mtClass) GrowableArray(10, mtClass); } _subgraph_entry_fields->append(static_field_offset); _subgraph_entry_fields->append(HeapShared::append_root(v)); } // Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs. // Only objects of boot classes can be included in sub-graph. void KlassSubGraphInfo::add_subgraph_object_klass(Klass* orig_k) { assert(CDSConfig::is_dumping_heap(), "dump time only"); if (_subgraph_object_klasses == nullptr) { _subgraph_object_klasses = new (mtClass) GrowableArray(50, mtClass); } if (_k == orig_k) { // Don't add the Klass containing the sub-graph to it's own klass // initialization list. return; } if (orig_k->is_instance_klass()) { #ifdef ASSERT InstanceKlass* ik = InstanceKlass::cast(orig_k); if (CDSConfig::is_dumping_method_handles()) { // -XX:AOTInitTestClass must be used carefully in regression tests to // include only classes that are safe to aot-initialize. assert(ik->class_loader() == nullptr || HeapShared::is_lambda_proxy_klass(ik) || AOTClassInitializer::has_test_class(), "we can archive only instances of boot classes or lambda proxy classes"); } else { assert(ik->class_loader() == nullptr, "must be boot class"); } #endif // vmClasses::xxx_klass() are not updated, need to check // the original Klass* if (orig_k == vmClasses::String_klass() || orig_k == vmClasses::Object_klass()) { // Initialized early during VM initialization. No need to be added // to the sub-graph object class list. return; } check_allowed_klass(InstanceKlass::cast(orig_k)); } else if (orig_k->is_objArray_klass()) { Klass* abk = ObjArrayKlass::cast(orig_k)->bottom_klass(); if (abk->is_instance_klass()) { assert(InstanceKlass::cast(abk)->defined_by_boot_loader(), "must be boot class"); check_allowed_klass(InstanceKlass::cast(ObjArrayKlass::cast(orig_k)->bottom_klass())); } if (orig_k == Universe::objectArrayKlass()) { // Initialized early during Universe::genesis. No need to be added // to the list. return; } } else { assert(orig_k->is_typeArray_klass(), "must be"); // Primitive type arrays are created early during Universe::genesis. return; } if (log_is_enabled(Debug, aot, heap)) { if (!_subgraph_object_klasses->contains(orig_k)) { ResourceMark rm; log_debug(aot, heap)("Adding klass %s", orig_k->external_name()); } } _subgraph_object_klasses->append_if_missing(orig_k); _has_non_early_klasses |= is_non_early_klass(orig_k); } void KlassSubGraphInfo::check_allowed_klass(InstanceKlass* ik) { #ifndef PRODUCT if (AOTClassInitializer::has_test_class()) { // The tests can cache arbitrary types of objects. return; } #endif if (ik->module()->name() == vmSymbols::java_base()) { assert(ik->package() != nullptr, "classes in java.base cannot be in unnamed package"); return; } const char* lambda_msg = ""; if (CDSConfig::is_dumping_method_handles()) { lambda_msg = ", or a lambda proxy class"; if (HeapShared::is_lambda_proxy_klass(ik) && (ik->class_loader() == nullptr || ik->class_loader() == SystemDictionary::java_platform_loader() || ik->class_loader() == SystemDictionary::java_system_loader())) { return; } } #ifndef PRODUCT if (!ik->module()->is_named() && ik->package() == nullptr && ArchiveHeapTestClass != nullptr) { // This class is loaded by ArchiveHeapTestClass return; } const char* testcls_msg = ", or a test class in an unnamed package of an unnamed module"; #else const char* testcls_msg = ""; #endif ResourceMark rm; log_error(aot, heap)("Class %s not allowed in archive heap. Must be in java.base%s%s", ik->external_name(), lambda_msg, testcls_msg); MetaspaceShared::unrecoverable_writing_error(); } bool KlassSubGraphInfo::is_non_early_klass(Klass* k) { if (k->is_objArray_klass()) { k = ObjArrayKlass::cast(k)->bottom_klass(); } if (k->is_instance_klass()) { if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) { ResourceMark rm; log_info(aot, heap)("non-early: %s", k->external_name()); return true; } else { return false; } } else { return false; } } // Initialize an archived subgraph_info_record from the given KlassSubGraphInfo. void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) { _k = ArchiveBuilder::get_buffered_klass(info->klass()); _entry_field_records = nullptr; _subgraph_object_klasses = nullptr; _is_full_module_graph = info->is_full_module_graph(); if (_is_full_module_graph) { // Consider all classes referenced by the full module graph as early -- we will be // allocating objects of these classes during JVMTI early phase, so they cannot // be processed by (non-early) JVMTI ClassFileLoadHook _has_non_early_klasses = false; } else { _has_non_early_klasses = info->has_non_early_klasses(); } if (_has_non_early_klasses) { ResourceMark rm; log_info(aot, heap)( "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled", _k->external_name()); } // populate the entry fields GrowableArray* entry_fields = info->subgraph_entry_fields(); if (entry_fields != nullptr) { int num_entry_fields = entry_fields->length(); assert(num_entry_fields % 2 == 0, "sanity"); _entry_field_records = ArchiveBuilder::new_ro_array(num_entry_fields); for (int i = 0 ; i < num_entry_fields; i++) { _entry_field_records->at_put(i, entry_fields->at(i)); } } // has the Klasses of all the objects that are referenced by this subgraph. // Copy those that need to be explicitly initialized into <_subgraph_object_klasses>. GrowableArray* recorded_klasses = info->subgraph_object_klasses(); if (recorded_klasses != nullptr) { // AOT-inited classes are automatically marked as "initialized" during bootstrap. When // programmatically loading a subgraph, we only need to explicitly initialize the classes // that are not aot-inited. int num_to_copy = 0; for (int i = 0; i < recorded_klasses->length(); i++) { Klass* subgraph_k = ArchiveBuilder::get_buffered_klass(recorded_klasses->at(i)); if (!subgraph_k->has_aot_initialized_mirror()) { num_to_copy ++; } } _subgraph_object_klasses = ArchiveBuilder::new_ro_array(num_to_copy); bool is_special = (_k == ArchiveBuilder::get_buffered_klass(vmClasses::Object_klass())); for (int i = 0, n = 0; i < recorded_klasses->length(); i++) { Klass* subgraph_k = ArchiveBuilder::get_buffered_klass(recorded_klasses->at(i)); if (subgraph_k->has_aot_initialized_mirror()) { continue; } if (log_is_enabled(Info, aot, heap)) { ResourceMark rm; const char* owner_name = is_special ? "" : _k->external_name(); if (subgraph_k->is_instance_klass()) { InstanceKlass* src_ik = InstanceKlass::cast(ArchiveBuilder::current()->get_source_addr(subgraph_k)); } log_info(aot, heap)( "Archived object klass %s (%2d) => %s", owner_name, n, subgraph_k->external_name()); } _subgraph_object_klasses->at_put(n, subgraph_k); ArchivePtrMarker::mark_pointer(_subgraph_object_klasses->adr_at(n)); n++; } } ArchivePtrMarker::mark_pointer(&_k); ArchivePtrMarker::mark_pointer(&_entry_field_records); ArchivePtrMarker::mark_pointer(&_subgraph_object_klasses); } class HeapShared::CopyKlassSubGraphInfoToArchive : StackObj { CompactHashtableWriter* _writer; public: CopyKlassSubGraphInfoToArchive(CompactHashtableWriter* writer) : _writer(writer) {} bool do_entry(Klass* klass, KlassSubGraphInfo& info) { if (info.subgraph_object_klasses() != nullptr || info.subgraph_entry_fields() != nullptr) { ArchivedKlassSubGraphInfoRecord* record = HeapShared::archive_subgraph_info(&info); Klass* buffered_k = ArchiveBuilder::get_buffered_klass(klass); unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary((address)buffered_k); u4 delta = ArchiveBuilder::current()->any_to_offset_u4(record); _writer->add(hash, delta); } return true; // keep on iterating } }; ArchivedKlassSubGraphInfoRecord* HeapShared::archive_subgraph_info(KlassSubGraphInfo* info) { ArchivedKlassSubGraphInfoRecord* record = (ArchivedKlassSubGraphInfoRecord*)ArchiveBuilder::ro_region_alloc(sizeof(ArchivedKlassSubGraphInfoRecord)); record->init(info); if (info == _dump_time_special_subgraph) { _run_time_special_subgraph = record; } return record; } // Build the records of archived subgraph infos, which include: // - Entry points to all subgraphs from the containing class mirror. The entry // points are static fields in the mirror. For each entry point, the field // offset, and value are recorded in the sub-graph // info. The value is stored back to the corresponding field at runtime. // - A list of klasses that need to be loaded/initialized before archived // java object sub-graph can be accessed at runtime. void HeapShared::write_subgraph_info_table() { // Allocate the contents of the hashtable(s) inside the RO region of the CDS archive. DumpTimeKlassSubGraphInfoTable* d_table = _dump_time_subgraph_info_table; CompactHashtableStats stats; _run_time_subgraph_info_table.reset(); CompactHashtableWriter writer(d_table->_count, &stats); CopyKlassSubGraphInfoToArchive copy(&writer); d_table->iterate(©); writer.dump(&_run_time_subgraph_info_table, "subgraphs"); #ifndef PRODUCT if (ArchiveHeapTestClass != nullptr) { size_t len = strlen(ArchiveHeapTestClass) + 1; Array* array = ArchiveBuilder::new_ro_array((int)len); strncpy(array->adr_at(0), ArchiveHeapTestClass, len); _archived_ArchiveHeapTestClass = array; } #endif if (log_is_enabled(Info, aot, heap)) { print_stats(); } } void HeapShared::add_root_segment(objArrayOop segment_oop) { assert(segment_oop != nullptr, "must be"); assert(ArchiveHeapLoader::is_in_use(), "must be"); if (_root_segments == nullptr) { _root_segments = new GrowableArrayCHeap(10); } _root_segments->push(OopHandle(Universe::vm_global(), segment_oop)); } void HeapShared::init_root_segment_sizes(int max_size_elems) { _root_segment_max_size_elems = max_size_elems; } void HeapShared::serialize_tables(SerializeClosure* soc) { #ifndef PRODUCT soc->do_ptr(&_archived_ArchiveHeapTestClass); if (soc->reading() && _archived_ArchiveHeapTestClass != nullptr) { _test_class_name = _archived_ArchiveHeapTestClass->adr_at(0); setup_test_class(_test_class_name); } #endif _run_time_subgraph_info_table.serialize_header(soc); soc->do_ptr(&_run_time_special_subgraph); } static void verify_the_heap(Klass* k, const char* which) { if (VerifyArchivedFields > 0) { ResourceMark rm; log_info(aot, heap)("Verify heap %s initializing static field(s) in %s", which, k->external_name()); VM_Verify verify_op; VMThread::execute(&verify_op); if (VerifyArchivedFields > 1 && is_init_completed()) { // At this time, the oop->klass() of some archived objects in the heap may not // have been loaded into the system dictionary yet. Nevertheless, oop->klass() should // have enough information (object size, oop maps, etc) so that a GC can be safely // performed. // // -XX:VerifyArchivedFields=2 force a GC to happen in such an early stage // to check for GC safety. log_info(aot, heap)("Trigger GC %s initializing static field(s) in %s", which, k->external_name()); FlagSetting fs1(VerifyBeforeGC, true); FlagSetting fs2(VerifyDuringGC, true); FlagSetting fs3(VerifyAfterGC, true); Universe::heap()->collect(GCCause::_java_lang_system_gc); } } } // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots() // have a valid klass. I.e., oopDesc::klass() must have already been resolved. // // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots. void HeapShared::resolve_classes(JavaThread* current) { assert(CDSConfig::is_using_archive(), "runtime only!"); if (!ArchiveHeapLoader::is_in_use()) { return; // nothing to do } resolve_classes_for_subgraphs(current, archive_subgraph_entry_fields); resolve_classes_for_subgraphs(current, fmg_archive_subgraph_entry_fields); } void HeapShared::resolve_classes_for_subgraphs(JavaThread* current, ArchivableStaticFieldInfo fields[]) { for (int i = 0; fields[i].valid(); i++) { ArchivableStaticFieldInfo* info = &fields[i]; TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name); InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name); assert(k != nullptr && k->defined_by_boot_loader(), "sanity"); resolve_classes_for_subgraph_of(current, k); } } void HeapShared::resolve_classes_for_subgraph_of(JavaThread* current, Klass* k) { JavaThread* THREAD = current; ExceptionMark em(THREAD); const ArchivedKlassSubGraphInfoRecord* record = resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; } if (record == nullptr) { clear_archived_roots_of(k); } } void HeapShared::initialize_java_lang_invoke(TRAPS) { if (CDSConfig::is_using_aot_linked_classes() || CDSConfig::is_dumping_method_handles()) { resolve_or_init("java/lang/invoke/Invokers$Holder", true, CHECK); resolve_or_init("java/lang/invoke/MethodHandle", true, CHECK); resolve_or_init("java/lang/invoke/MethodHandleNatives", true, CHECK); resolve_or_init("java/lang/invoke/DirectMethodHandle$Holder", true, CHECK); resolve_or_init("java/lang/invoke/DelegatingMethodHandle$Holder", true, CHECK); resolve_or_init("java/lang/invoke/LambdaForm$Holder", true, CHECK); resolve_or_init("java/lang/invoke/BoundMethodHandle$Species_L", true, CHECK); } } // Initialize the InstanceKlasses of objects that are reachable from the following roots: // - interned strings // - Klass::java_mirror() -- including aot-initialized mirrors such as those of Enum klasses. // - ConstantPool::resolved_references() // - Universe::_exception_instance() // // For example, if this enum class is initialized at AOT cache assembly time: // // enum Fruit { // APPLE, ORANGE, BANANA; // static final Set HAVE_SEEDS = new HashSet<>(Arrays.asList(APPLE, ORANGE)); // } // // the aot-initialized mirror of Fruit has a static field that references HashSet, which // should be initialized before any Java code can access the Fruit class. Note that // HashSet itself doesn't necessary need to be an aot-initialized class. void HeapShared::init_classes_for_special_subgraph(Handle class_loader, TRAPS) { if (!ArchiveHeapLoader::is_in_use()) { return; } assert( _run_time_special_subgraph != nullptr, "must be"); Array* klasses = _run_time_special_subgraph->subgraph_object_klasses(); if (klasses != nullptr) { for (int pass = 0; pass < 2; pass ++) { for (int i = 0; i < klasses->length(); i++) { Klass* k = klasses->at(i); if (k->class_loader_data() == nullptr) { // This class is not yet loaded. We will initialize it in a later phase. // For example, we have loaded only AOTLinkedClassCategory::BOOT1 classes // but k is part of AOTLinkedClassCategory::BOOT2. continue; } if (k->class_loader() == class_loader()) { if (pass == 0) { if (k->is_instance_klass()) { InstanceKlass::cast(k)->link_class(CHECK); } } else { resolve_or_init(k, /*do_init*/true, CHECK); } } } } } } void HeapShared::initialize_from_archived_subgraph(JavaThread* current, Klass* k) { JavaThread* THREAD = current; if (!ArchiveHeapLoader::is_in_use()) { return; // nothing to do } if (k->name()->equals("jdk/internal/module/ArchivedModuleGraph") && !CDSConfig::is_using_optimized_module_handling() && // archive was created with --module-path AOTClassLocationConfig::runtime()->num_module_paths() > 0) { // ArchivedModuleGraph was created with a --module-path that's different than the runtime --module-path. // Thus, it might contain references to modules that do not exist at runtime. We cannot use it. log_info(aot, heap)("Skip initializing ArchivedModuleGraph subgraph: is_using_optimized_module_handling=%s num_module_paths=%d", BOOL_TO_STR(CDSConfig::is_using_optimized_module_handling()), AOTClassLocationConfig::runtime()->num_module_paths()); return; } ExceptionMark em(THREAD); const ArchivedKlassSubGraphInfoRecord* record = resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; // None of the field value will be set if there was an exception when initializing the classes. // The java code will not see any of the archived objects in the // subgraphs referenced from k in this case. return; } if (record != nullptr) { init_archived_fields_for(k, record); } } const ArchivedKlassSubGraphInfoRecord* HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) { assert(!CDSConfig::is_dumping_heap(), "Should not be called when dumping heap"); if (!k->is_shared()) { return nullptr; } unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k); const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0); #ifndef PRODUCT if (_test_class_name != nullptr && k->name()->equals(_test_class_name) && record != nullptr) { _test_class = k; _test_class_record = record; } #endif // Initialize from archived data. Currently this is done only // during VM initialization time. No lock is needed. if (record == nullptr) { if (log_is_enabled(Info, aot, heap)) { ResourceMark rm(THREAD); log_info(aot, heap)("subgraph %s is not recorded", k->external_name()); } return nullptr; } else { if (record->is_full_module_graph() && !CDSConfig::is_using_full_module_graph()) { if (log_is_enabled(Info, aot, heap)) { ResourceMark rm(THREAD); log_info(aot, heap)("subgraph %s cannot be used because full module graph is disabled", k->external_name()); } return nullptr; } if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) { if (log_is_enabled(Info, aot, heap)) { ResourceMark rm(THREAD); log_info(aot, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled", k->external_name()); } return nullptr; } if (log_is_enabled(Info, aot, heap)) { ResourceMark rm; log_info(aot, heap)("%s subgraph %s ", do_init ? "init" : "resolve", k->external_name()); } resolve_or_init(k, do_init, CHECK_NULL); // Load/link/initialize the klasses of the objects in the subgraph. // nullptr class loader is used. Array* klasses = record->subgraph_object_klasses(); if (klasses != nullptr) { for (int i = 0; i < klasses->length(); i++) { Klass* klass = klasses->at(i); if (!klass->is_shared()) { return nullptr; } resolve_or_init(klass, do_init, CHECK_NULL); } } } return record; } void HeapShared::resolve_or_init(const char* klass_name, bool do_init, TRAPS) { TempNewSymbol klass_name_sym = SymbolTable::new_symbol(klass_name); InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name_sym); if (k == nullptr) { return; } assert(k->defined_by_boot_loader(), "sanity"); resolve_or_init(k, false, CHECK); if (do_init) { resolve_or_init(k, true, CHECK); } } void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) { if (!do_init) { if (k->class_loader_data() == nullptr) { Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK); assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook"); } } else { assert(k->class_loader_data() != nullptr, "must have been resolved by HeapShared::resolve_classes"); if (k->is_instance_klass()) { InstanceKlass* ik = InstanceKlass::cast(k); ik->initialize(CHECK); } else if (k->is_objArray_klass()) { ObjArrayKlass* oak = ObjArrayKlass::cast(k); oak->initialize(CHECK); } } } void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record) { verify_the_heap(k, "before"); // Load the subgraph entry fields from the record and store them back to // the corresponding fields within the mirror. oop m = k->java_mirror(); Array* entry_field_records = record->entry_field_records(); if (entry_field_records != nullptr) { int efr_len = entry_field_records->length(); assert(efr_len % 2 == 0, "sanity"); for (int i = 0; i < efr_len; i += 2) { int field_offset = entry_field_records->at(i); int root_index = entry_field_records->at(i+1); oop v = get_root(root_index, /*clear=*/true); if (k->has_aot_initialized_mirror()) { assert(v == m->obj_field(field_offset), "must be aot-initialized"); } else { m->obj_field_put(field_offset, v); } log_debug(aot, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v)); } // Done. Java code can see the archived sub-graphs referenced from k's // mirror after this point. if (log_is_enabled(Info, aot, heap)) { ResourceMark rm; log_info(aot, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s%s", k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "", k->has_aot_initialized_mirror() ? " (aot-inited)" : ""); } } verify_the_heap(k, "after "); } void HeapShared::clear_archived_roots_of(Klass* k) { unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary_quick(k); const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0); if (record != nullptr) { Array* entry_field_records = record->entry_field_records(); if (entry_field_records != nullptr) { int efr_len = entry_field_records->length(); assert(efr_len % 2 == 0, "sanity"); for (int i = 0; i < efr_len; i += 2) { int root_index = entry_field_records->at(i+1); clear_root(root_index); } } } } // Push all oop fields (or oop array elemenets in case of an objArray) in // _referencing_obj onto the _stack. class HeapShared::OopFieldPusher: public BasicOopIterateClosure { PendingOopStack* _stack; GrowableArray _found_oop_fields; int _level; bool _record_klasses_only; KlassSubGraphInfo* _subgraph_info; oop _referencing_obj; bool _is_java_lang_ref; public: OopFieldPusher(PendingOopStack* stack, int level, bool record_klasses_only, KlassSubGraphInfo* subgraph_info, oop orig) : _stack(stack), _found_oop_fields(), _level(level), _record_klasses_only(record_klasses_only), _subgraph_info(subgraph_info), _referencing_obj(orig) { _is_java_lang_ref = AOTReferenceObjSupport::check_if_ref_obj(orig); } void do_oop(narrowOop *p) { OopFieldPusher::do_oop_work(p); } void do_oop( oop *p) { OopFieldPusher::do_oop_work(p); } ~OopFieldPusher() { while (_found_oop_fields.length() > 0) { // This produces the exact same traversal order as the previous version // of OopFieldPusher that recurses on the C stack -- a depth-first search, // walking the oop fields in _referencing_obj by ascending field offsets. oop obj = _found_oop_fields.pop(); _stack->push(PendingOop(obj, _referencing_obj, _level + 1)); } } protected: template void do_oop_work(T *p) { int field_offset = pointer_delta_as_int((char*)p, cast_from_oop(_referencing_obj)); oop obj = HeapAccess::oop_load_at(_referencing_obj, field_offset); if (!CompressedOops::is_null(obj)) { if (_is_java_lang_ref && AOTReferenceObjSupport::skip_field(field_offset)) { // Do not follow these fields. They will be cleared to null. return; } if (!_record_klasses_only && log_is_enabled(Debug, aot, heap)) { ResourceMark rm; log_debug(aot, heap)("(%d) %s[%d] ==> " PTR_FORMAT " size %zu %s", _level, _referencing_obj->klass()->external_name(), field_offset, p2i(obj), obj->size() * HeapWordSize, obj->klass()->external_name()); if (log_is_enabled(Trace, aot, heap)) { LogTarget(Trace, aot, heap) log; LogStream out(log); obj->print_on(&out); } } _found_oop_fields.push(obj); } } public: oop referencing_obj() { return _referencing_obj; } KlassSubGraphInfo* subgraph_info() { return _subgraph_info; } }; // Checks if an oop has any non-null oop fields class PointsToOopsChecker : public BasicOopIterateClosure { bool _result; template void check(T *p) { _result |= (HeapAccess<>::oop_load(p) != nullptr); } public: PointsToOopsChecker() : _result(false) {} void do_oop(narrowOop *p) { check(p); } void do_oop( oop *p) { check(p); } bool result() { return _result; } }; HeapShared::CachedOopInfo HeapShared::make_cached_oop_info(oop obj, oop referrer) { PointsToOopsChecker points_to_oops_checker; obj->oop_iterate(&points_to_oops_checker); return CachedOopInfo(referrer, points_to_oops_checker.result()); } void HeapShared::init_box_classes(TRAPS) { if (ArchiveHeapLoader::is_in_use()) { vmClasses::Boolean_klass()->initialize(CHECK); vmClasses::Character_klass()->initialize(CHECK); vmClasses::Float_klass()->initialize(CHECK); vmClasses::Double_klass()->initialize(CHECK); vmClasses::Byte_klass()->initialize(CHECK); vmClasses::Short_klass()->initialize(CHECK); vmClasses::Integer_klass()->initialize(CHECK); vmClasses::Long_klass()->initialize(CHECK); vmClasses::Void_klass()->initialize(CHECK); } } // (1) If orig_obj has not been archived yet, archive it. // (2) If orig_obj has not been seen yet (since start_recording_subgraph() was called), // trace all objects that are reachable from it, and make sure these objects are archived. // (3) Record the klasses of all objects that are reachable from orig_obj (including those that // were already archived when this function is called) bool HeapShared::archive_reachable_objects_from(int level, KlassSubGraphInfo* subgraph_info, oop orig_obj) { assert(orig_obj != nullptr, "must be"); PendingOopStack stack; stack.push(PendingOop(orig_obj, nullptr, level)); while (stack.length() > 0) { PendingOop po = stack.pop(); _object_being_archived = po; bool status = walk_one_object(&stack, po.level(), subgraph_info, po.obj(), po.referrer()); _object_being_archived = PendingOop(); if (!status) { // Don't archive a subgraph root that's too big. For archives static fields, that's OK // as the Java code will take care of initializing this field dynamically. assert(level == 1, "VM should have exited with unarchivable objects for _level > 1"); return false; } } return true; } bool HeapShared::walk_one_object(PendingOopStack* stack, int level, KlassSubGraphInfo* subgraph_info, oop orig_obj, oop referrer) { assert(orig_obj != nullptr, "must be"); if (!JavaClasses::is_supported_for_archiving(orig_obj)) { // This object has injected fields that cannot be supported easily, so we disallow them for now. // If you get an error here, you probably made a change in the JDK library that has added // these objects that are referenced (directly or indirectly) by static fields. ResourceMark rm; log_error(aot, heap)("Cannot archive object " PTR_FORMAT " of class %s", p2i(orig_obj), orig_obj->klass()->external_name()); debug_trace(); MetaspaceShared::unrecoverable_writing_error(); } if (log_is_enabled(Debug, aot, heap) && java_lang_Class::is_instance(orig_obj)) { ResourceMark rm; LogTarget(Debug, aot, heap) log; LogStream out(log); out.print("Found java mirror " PTR_FORMAT " ", p2i(orig_obj)); Klass* k = java_lang_Class::as_Klass(orig_obj); if (k != nullptr) { out.print("%s", k->external_name()); } else { out.print("primitive"); } out.print_cr("; scratch mirror = " PTR_FORMAT, p2i(scratch_java_mirror(orig_obj))); } if (CDSConfig::is_initing_classes_at_dump_time()) { if (java_lang_Class::is_instance(orig_obj)) { orig_obj = scratch_java_mirror(orig_obj); assert(orig_obj != nullptr, "must be archived"); } } else if (java_lang_Class::is_instance(orig_obj) && subgraph_info != _dump_time_special_subgraph) { // Without CDSConfig::is_initing_classes_at_dump_time(), we only allow archived objects to // point to the mirrors of (1) j.l.Object, (2) primitive classes, and (3) box classes. These are initialized // very early by HeapShared::init_box_classes(). if (orig_obj == vmClasses::Object_klass()->java_mirror() || java_lang_Class::is_primitive(orig_obj) || orig_obj == vmClasses::Boolean_klass()->java_mirror() || orig_obj == vmClasses::Character_klass()->java_mirror() || orig_obj == vmClasses::Float_klass()->java_mirror() || orig_obj == vmClasses::Double_klass()->java_mirror() || orig_obj == vmClasses::Byte_klass()->java_mirror() || orig_obj == vmClasses::Short_klass()->java_mirror() || orig_obj == vmClasses::Integer_klass()->java_mirror() || orig_obj == vmClasses::Long_klass()->java_mirror() || orig_obj == vmClasses::Void_klass()->java_mirror()) { orig_obj = scratch_java_mirror(orig_obj); assert(orig_obj != nullptr, "must be archived"); } else { // If you get an error here, you probably made a change in the JDK library that has added a Class // object that is referenced (directly or indirectly) by an ArchivableStaticFieldInfo // defined at the top of this file. log_error(aot, heap)("(%d) Unknown java.lang.Class object is in the archived sub-graph", level); debug_trace(); MetaspaceShared::unrecoverable_writing_error(); } } if (has_been_seen_during_subgraph_recording(orig_obj)) { // orig_obj has already been archived and traced. Nothing more to do. return true; } else { set_has_been_seen_during_subgraph_recording(orig_obj); } bool already_archived = has_been_archived(orig_obj); bool record_klasses_only = already_archived; if (!already_archived) { ++_num_new_archived_objs; if (!archive_object(orig_obj, referrer, subgraph_info)) { // Skip archiving the sub-graph referenced from the current entry field. ResourceMark rm; log_error(aot, heap)( "Cannot archive the sub-graph referenced from %s object (" PTR_FORMAT ") size %zu, skipped.", orig_obj->klass()->external_name(), p2i(orig_obj), orig_obj->size() * HeapWordSize); if (level == 1) { // Don't archive a subgraph root that's too big. For archives static fields, that's OK // as the Java code will take care of initializing this field dynamically. return false; } else { // We don't know how to handle an object that has been archived, but some of its reachable // objects cannot be archived. Bail out for now. We might need to fix this in the future if // we have a real use case. MetaspaceShared::unrecoverable_writing_error(); } } } Klass *orig_k = orig_obj->klass(); subgraph_info->add_subgraph_object_klass(orig_k); { // Find all the oops that are referenced by orig_obj, push them onto the stack // so we can work on them next. ResourceMark rm; OopFieldPusher pusher(stack, level, record_klasses_only, subgraph_info, orig_obj); orig_obj->oop_iterate(&pusher); } if (CDSConfig::is_initing_classes_at_dump_time()) { // The enum klasses are archived with aot-initialized mirror. // See AOTClassInitializer::can_archive_initialized_mirror(). } else { if (CDSEnumKlass::is_enum_obj(orig_obj)) { CDSEnumKlass::handle_enum_obj(level + 1, subgraph_info, orig_obj); } } return true; } // // Start from the given static field in a java mirror and archive the // complete sub-graph of java heap objects that are reached directly // or indirectly from the starting object by following references. // Sub-graph archiving restrictions (current): // // - All classes of objects in the archived sub-graph (including the // entry class) must be boot class only. // - No java.lang.Class instance (java mirror) can be included inside // an archived sub-graph. Mirror can only be the sub-graph entry object. // // The Java heap object sub-graph archiving process (see OopFieldPusher): // // 1) Java object sub-graph archiving starts from a given static field // within a Class instance (java mirror). If the static field is a // reference field and points to a non-null java object, proceed to // the next step. // // 2) Archives the referenced java object. If an archived copy of the // current object already exists, updates the pointer in the archived // copy of the referencing object to point to the current archived object. // Otherwise, proceed to the next step. // // 3) Follows all references within the current java object and recursively // archive the sub-graph of objects starting from each reference. // // 4) Updates the pointer in the archived copy of referencing object to // point to the current archived object. // // 5) The Klass of the current java object is added to the list of Klasses // for loading and initializing before any object in the archived graph can // be accessed at runtime. // void HeapShared::archive_reachable_objects_from_static_field(InstanceKlass *k, const char* klass_name, int field_offset, const char* field_name) { assert(CDSConfig::is_dumping_heap(), "dump time only"); assert(k->defined_by_boot_loader(), "must be boot class"); oop m = k->java_mirror(); KlassSubGraphInfo* subgraph_info = get_subgraph_info(k); oop f = m->obj_field(field_offset); log_debug(aot, heap)("Start archiving from: %s::%s (" PTR_FORMAT ")", klass_name, field_name, p2i(f)); if (!CompressedOops::is_null(f)) { if (log_is_enabled(Trace, aot, heap)) { LogTarget(Trace, aot, heap) log; LogStream out(log); f->print_on(&out); } bool success = archive_reachable_objects_from(1, subgraph_info, f); if (!success) { log_error(aot, heap)("Archiving failed %s::%s (some reachable objects cannot be archived)", klass_name, field_name); } else { // Note: the field value is not preserved in the archived mirror. // Record the field as a new subGraph entry point. The recorded // information is restored from the archive at runtime. subgraph_info->add_subgraph_entry_field(field_offset, f); log_info(aot, heap)("Archived field %s::%s => " PTR_FORMAT, klass_name, field_name, p2i(f)); } } else { // The field contains null, we still need to record the entry point, // so it can be restored at runtime. subgraph_info->add_subgraph_entry_field(field_offset, nullptr); } } #ifndef PRODUCT class VerifySharedOopClosure: public BasicOopIterateClosure { public: void do_oop(narrowOop *p) { VerifySharedOopClosure::do_oop_work(p); } void do_oop( oop *p) { VerifySharedOopClosure::do_oop_work(p); } protected: template void do_oop_work(T *p) { oop obj = RawAccess<>::oop_load(p); if (!CompressedOops::is_null(obj)) { HeapShared::verify_reachable_objects_from(obj); } } }; void HeapShared::verify_subgraph_from_static_field(InstanceKlass* k, int field_offset) { assert(CDSConfig::is_dumping_heap(), "dump time only"); assert(k->defined_by_boot_loader(), "must be boot class"); oop m = k->java_mirror(); oop f = m->obj_field(field_offset); if (!CompressedOops::is_null(f)) { verify_subgraph_from(f); } } void HeapShared::verify_subgraph_from(oop orig_obj) { if (!has_been_archived(orig_obj)) { // It's OK for the root of a subgraph to be not archived. See comments in // archive_reachable_objects_from(). return; } // Verify that all objects reachable from orig_obj are archived. init_seen_objects_table(); verify_reachable_objects_from(orig_obj); delete_seen_objects_table(); } void HeapShared::verify_reachable_objects_from(oop obj) { _num_total_verifications ++; if (java_lang_Class::is_instance(obj)) { obj = scratch_java_mirror(obj); assert(obj != nullptr, "must be"); } if (!has_been_seen_during_subgraph_recording(obj)) { set_has_been_seen_during_subgraph_recording(obj); assert(has_been_archived(obj), "must be"); VerifySharedOopClosure walker; obj->oop_iterate(&walker); } } #endif void HeapShared::check_special_subgraph_classes() { if (CDSConfig::is_initing_classes_at_dump_time()) { // We can have aot-initialized classes (such as Enums) that can reference objects // of arbitrary types. Currently, we trust the JEP 483 implementation to only // aot-initialize classes that are "safe". // // TODO: we need an automatic tool that checks the safety of aot-initialized // classes (when we extend the set of aot-initialized classes beyond JEP 483) return; } else { // In this case, the special subgraph should contain a few specific types GrowableArray* klasses = _dump_time_special_subgraph->subgraph_object_klasses(); int num = klasses->length(); for (int i = 0; i < num; i++) { Klass* subgraph_k = klasses->at(i); Symbol* name = subgraph_k->name(); if (subgraph_k->is_instance_klass() && name != vmSymbols::java_lang_Class() && name != vmSymbols::java_lang_String() && name != vmSymbols::java_lang_ArithmeticException() && name != vmSymbols::java_lang_ArrayIndexOutOfBoundsException() && name != vmSymbols::java_lang_ArrayStoreException() && name != vmSymbols::java_lang_ClassCastException() && name != vmSymbols::java_lang_InternalError() && name != vmSymbols::java_lang_NullPointerException()) { ResourceMark rm; fatal("special subgraph cannot have objects of type %s", subgraph_k->external_name()); } } } } HeapShared::SeenObjectsTable* HeapShared::_seen_objects_table = nullptr; HeapShared::PendingOop HeapShared::_object_being_archived; int HeapShared::_num_new_walked_objs; int HeapShared::_num_new_archived_objs; int HeapShared::_num_old_recorded_klasses; int HeapShared::_num_total_subgraph_recordings = 0; int HeapShared::_num_total_walked_objs = 0; int HeapShared::_num_total_archived_objs = 0; int HeapShared::_num_total_recorded_klasses = 0; int HeapShared::_num_total_verifications = 0; bool HeapShared::has_been_seen_during_subgraph_recording(oop obj) { return _seen_objects_table->get(obj) != nullptr; } void HeapShared::set_has_been_seen_during_subgraph_recording(oop obj) { assert(!has_been_seen_during_subgraph_recording(obj), "sanity"); _seen_objects_table->put_when_absent(obj, true); _seen_objects_table->maybe_grow(); ++ _num_new_walked_objs; } void HeapShared::start_recording_subgraph(InstanceKlass *k, const char* class_name, bool is_full_module_graph) { log_info(aot, heap)("Start recording subgraph(s) for archived fields in %s", class_name); init_subgraph_info(k, is_full_module_graph); init_seen_objects_table(); _num_new_walked_objs = 0; _num_new_archived_objs = 0; _num_old_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses(); } void HeapShared::done_recording_subgraph(InstanceKlass *k, const char* class_name) { int num_new_recorded_klasses = get_subgraph_info(k)->num_subgraph_object_klasses() - _num_old_recorded_klasses; log_info(aot, heap)("Done recording subgraph(s) for archived fields in %s: " "walked %d objs, archived %d new objs, recorded %d classes", class_name, _num_new_walked_objs, _num_new_archived_objs, num_new_recorded_klasses); delete_seen_objects_table(); _num_total_subgraph_recordings ++; _num_total_walked_objs += _num_new_walked_objs; _num_total_archived_objs += _num_new_archived_objs; _num_total_recorded_klasses += num_new_recorded_klasses; } class ArchivableStaticFieldFinder: public FieldClosure { InstanceKlass* _ik; Symbol* _field_name; bool _found; int _offset; public: ArchivableStaticFieldFinder(InstanceKlass* ik, Symbol* field_name) : _ik(ik), _field_name(field_name), _found(false), _offset(-1) {} virtual void do_field(fieldDescriptor* fd) { if (fd->name() == _field_name) { assert(!_found, "fields can never be overloaded"); if (is_reference_type(fd->field_type())) { _found = true; _offset = fd->offset(); } } } bool found() { return _found; } int offset() { return _offset; } }; void HeapShared::init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[], TRAPS) { for (int i = 0; fields[i].valid(); i++) { ArchivableStaticFieldInfo* info = &fields[i]; TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name); TempNewSymbol field_name = SymbolTable::new_symbol(info->field_name); ResourceMark rm; // for stringStream::as_string() etc. #ifndef PRODUCT bool is_test_class = (ArchiveHeapTestClass != nullptr) && (strcmp(info->klass_name, ArchiveHeapTestClass) == 0); const char* test_class_name = ArchiveHeapTestClass; #else bool is_test_class = false; const char* test_class_name = ""; // avoid C++ printf checks warnings. #endif if (is_test_class) { log_warning(aot)("Loading ArchiveHeapTestClass %s ...", test_class_name); } Klass* k = SystemDictionary::resolve_or_fail(klass_name, true, THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; stringStream st; st.print("Fail to initialize archive heap: %s cannot be loaded by the boot loader", info->klass_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } if (!k->is_instance_klass()) { stringStream st; st.print("Fail to initialize archive heap: %s is not an instance class", info->klass_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } InstanceKlass* ik = InstanceKlass::cast(k); assert(InstanceKlass::cast(ik)->defined_by_boot_loader(), "Only support boot classes"); if (is_test_class) { if (ik->module()->is_named()) { // We don't want ArchiveHeapTestClass to be abused to easily load/initialize arbitrary // core-lib classes. You need to at least append to the bootclasspath. stringStream st; st.print("ArchiveHeapTestClass %s is not in unnamed module", test_class_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } if (ik->package() != nullptr) { // This restriction makes HeapShared::is_a_test_class_in_unnamed_module() easy. stringStream st; st.print("ArchiveHeapTestClass %s is not in unnamed package", test_class_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } } else { if (ik->module()->name() != vmSymbols::java_base()) { // We don't want to deal with cases when a module is unavailable at runtime. // FUTURE -- load from archived heap only when module graph has not changed // between dump and runtime. stringStream st; st.print("%s is not in java.base module", info->klass_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } } if (is_test_class) { log_warning(aot)("Initializing ArchiveHeapTestClass %s ...", test_class_name); } ik->initialize(CHECK); ArchivableStaticFieldFinder finder(ik, field_name); ik->do_local_static_fields(&finder); if (!finder.found()) { stringStream st; st.print("Unable to find the static T_OBJECT field %s::%s", info->klass_name, info->field_name); THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), st.as_string()); } info->klass = ik; info->offset = finder.offset(); } } void HeapShared::init_subgraph_entry_fields(TRAPS) { assert(CDSConfig::is_dumping_heap(), "must be"); _dump_time_subgraph_info_table = new (mtClass)DumpTimeKlassSubGraphInfoTable(); init_subgraph_entry_fields(archive_subgraph_entry_fields, CHECK); if (CDSConfig::is_dumping_full_module_graph()) { init_subgraph_entry_fields(fmg_archive_subgraph_entry_fields, CHECK); } } #ifndef PRODUCT void HeapShared::setup_test_class(const char* test_class_name) { ArchivableStaticFieldInfo* p = archive_subgraph_entry_fields; int num_slots = sizeof(archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo); assert(p[num_slots - 2].klass_name == nullptr, "must have empty slot that's patched below"); assert(p[num_slots - 1].klass_name == nullptr, "must have empty slot that marks the end of the list"); if (test_class_name != nullptr) { p[num_slots - 2].klass_name = test_class_name; p[num_slots - 2].field_name = ARCHIVE_TEST_FIELD_NAME; } } // See if ik is one of the test classes that are pulled in by -XX:ArchiveHeapTestClass // during runtime. This may be called before the module system is initialized so // we cannot rely on InstanceKlass::module(), etc. bool HeapShared::is_a_test_class_in_unnamed_module(Klass* ik) { if (_test_class != nullptr) { if (ik == _test_class) { return true; } Array* klasses = _test_class_record->subgraph_object_klasses(); if (klasses == nullptr) { return false; } for (int i = 0; i < klasses->length(); i++) { Klass* k = klasses->at(i); if (k == ik) { Symbol* name; if (k->is_instance_klass()) { name = InstanceKlass::cast(k)->name(); } else if (k->is_objArray_klass()) { Klass* bk = ObjArrayKlass::cast(k)->bottom_klass(); if (!bk->is_instance_klass()) { return false; } name = bk->name(); } else { return false; } // See KlassSubGraphInfo::check_allowed_klass() - we only allow test classes // to be: // (A) java.base classes (which must not be in the unnamed module) // (B) test classes which must be in the unnamed package of the unnamed module. // So if we see a '/' character in the class name, it must be in (A); // otherwise it must be in (B). if (name->index_of_at(0, "/", 1) >= 0) { return false; // (A) } return true; // (B) } } } return false; } void HeapShared::initialize_test_class_from_archive(JavaThread* current) { Klass* k = _test_class; if (k != nullptr && ArchiveHeapLoader::is_in_use()) { JavaThread* THREAD = current; ExceptionMark em(THREAD); const ArchivedKlassSubGraphInfoRecord* record = resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD); // The _test_class is in the unnamed module, so it can't call CDS.initializeFromArchive() // from its method. So we set up its "archivedObjects" field first, before // calling its . This is not strictly clean, but it's a convenient way to write unit // test cases (see test/hotspot/jtreg/runtime/cds/appcds/cacheObject/ArchiveHeapTestClass.java). if (record != nullptr) { init_archived_fields_for(k, record); } resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD); } } #endif void HeapShared::init_for_dumping(TRAPS) { if (CDSConfig::is_dumping_heap()) { setup_test_class(ArchiveHeapTestClass); _dumped_interned_strings = new (mtClass)DumpedInternedStrings(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE); init_subgraph_entry_fields(CHECK); } } void HeapShared::archive_object_subgraphs(ArchivableStaticFieldInfo fields[], bool is_full_module_graph) { _num_total_subgraph_recordings = 0; _num_total_walked_objs = 0; _num_total_archived_objs = 0; _num_total_recorded_klasses = 0; _num_total_verifications = 0; // For each class X that has one or more archived fields: // [1] Dump the subgraph of each archived field // [2] Create a list of all the class of the objects that can be reached // by any of these static fields. // At runtime, these classes are initialized before X's archived fields // are restored by HeapShared::initialize_from_archived_subgraph(). for (int i = 0; fields[i].valid(); ) { ArchivableStaticFieldInfo* info = &fields[i]; const char* klass_name = info->klass_name; start_recording_subgraph(info->klass, klass_name, is_full_module_graph); // If you have specified consecutive fields of the same klass in // fields[], these will be archived in the same // {start_recording_subgraph ... done_recording_subgraph} pass to // save time. for (; fields[i].valid(); i++) { ArchivableStaticFieldInfo* f = &fields[i]; if (f->klass_name != klass_name) { break; } archive_reachable_objects_from_static_field(f->klass, f->klass_name, f->offset, f->field_name); } done_recording_subgraph(info->klass, klass_name); } log_info(aot, heap)("Archived subgraph records = %d", _num_total_subgraph_recordings); log_info(aot, heap)(" Walked %d objects", _num_total_walked_objs); log_info(aot, heap)(" Archived %d objects", _num_total_archived_objs); log_info(aot, heap)(" Recorded %d klasses", _num_total_recorded_klasses); #ifndef PRODUCT for (int i = 0; fields[i].valid(); i++) { ArchivableStaticFieldInfo* f = &fields[i]; verify_subgraph_from_static_field(f->klass, f->offset); } log_info(aot, heap)(" Verified %d references", _num_total_verifications); #endif } // Keep track of the contents of the archived interned string table. This table // is used only by CDSHeapVerifier. void HeapShared::add_to_dumped_interned_strings(oop string) { assert_at_safepoint(); // DumpedInternedStrings uses raw oops assert(!ArchiveHeapWriter::is_string_too_large_to_archive(string), "must be"); bool created; _dumped_interned_strings->put_if_absent(string, true, &created); if (created) { // Prevent string deduplication from changing the value field to // something not in the archive. java_lang_String::set_deduplication_forbidden(string); _dumped_interned_strings->maybe_grow(); } } bool HeapShared::is_dumped_interned_string(oop o) { return _dumped_interned_strings->get(o) != nullptr; } void HeapShared::debug_trace() { ResourceMark rm; oop referrer = _object_being_archived.referrer(); if (referrer != nullptr) { LogStream ls(Log(aot, heap)::error()); ls.print_cr("Reference trace"); CDSHeapVerifier::trace_to_root(&ls, referrer); } } #ifndef PRODUCT // At dump-time, find the location of all the non-null oop pointers in an archived heap // region. This way we can quickly relocate all the pointers without using // BasicOopIterateClosure at runtime. class FindEmbeddedNonNullPointers: public BasicOopIterateClosure { void* _start; BitMap *_oopmap; int _num_total_oops; int _num_null_oops; public: FindEmbeddedNonNullPointers(void* start, BitMap* oopmap) : _start(start), _oopmap(oopmap), _num_total_oops(0), _num_null_oops(0) {} virtual void do_oop(narrowOop* p) { assert(UseCompressedOops, "sanity"); _num_total_oops ++; narrowOop v = *p; if (!CompressedOops::is_null(v)) { size_t idx = p - (narrowOop*)_start; _oopmap->set_bit(idx); } else { _num_null_oops ++; } } virtual void do_oop(oop* p) { assert(!UseCompressedOops, "sanity"); _num_total_oops ++; if ((*p) != nullptr) { size_t idx = p - (oop*)_start; _oopmap->set_bit(idx); } else { _num_null_oops ++; } } int num_total_oops() const { return _num_total_oops; } int num_null_oops() const { return _num_null_oops; } }; #endif void HeapShared::count_allocation(size_t size) { _total_obj_count ++; _total_obj_size += size; for (int i = 0; i < ALLOC_STAT_SLOTS; i++) { if (size <= (size_t(1) << i)) { _alloc_count[i] ++; _alloc_size[i] += size; return; } } } static double avg_size(size_t size, size_t count) { double avg = 0; if (count > 0) { avg = double(size * HeapWordSize) / double(count); } return avg; } void HeapShared::print_stats() { size_t huge_count = _total_obj_count; size_t huge_size = _total_obj_size; for (int i = 0; i < ALLOC_STAT_SLOTS; i++) { size_t byte_size_limit = (size_t(1) << i) * HeapWordSize; size_t count = _alloc_count[i]; size_t size = _alloc_size[i]; log_info(aot, heap)("%8zu objects are <= %-6zu" " bytes (total %8zu bytes, avg %8.1f bytes)", count, byte_size_limit, size * HeapWordSize, avg_size(size, count)); huge_count -= count; huge_size -= size; } log_info(aot, heap)("%8zu huge objects (total %8zu bytes" ", avg %8.1f bytes)", huge_count, huge_size * HeapWordSize, avg_size(huge_size, huge_count)); log_info(aot, heap)("%8zu total objects (total %8zu bytes" ", avg %8.1f bytes)", _total_obj_count, _total_obj_size * HeapWordSize, avg_size(_total_obj_size, _total_obj_count)); } bool HeapShared::is_archived_boot_layer_available(JavaThread* current) { TempNewSymbol klass_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_CLASS); InstanceKlass* k = SystemDictionary::find_instance_klass(current, klass_name, Handle()); if (k == nullptr) { return false; } else { TempNewSymbol field_name = SymbolTable::new_symbol(ARCHIVED_BOOT_LAYER_FIELD); TempNewSymbol field_signature = SymbolTable::new_symbol("Ljdk/internal/module/ArchivedBootLayer;"); fieldDescriptor fd; if (k->find_field(field_name, field_signature, true, &fd) != nullptr) { oop m = k->java_mirror(); oop f = m->obj_field(fd.offset()); if (CompressedOops::is_null(f)) { return false; } } else { return false; } } return true; } #endif // INCLUDE_CDS_JAVA_HEAP