/* * Copyright (c) 2024, 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. * */ #ifndef SHARE_CDS_AOTMAPPEDHEAPWRITER_HPP #define SHARE_CDS_AOTMAPPEDHEAPWRITER_HPP #include "cds/aotMapLogger.hpp" #include "cds/heapShared.hpp" #include "memory/allocation.hpp" #include "memory/allStatic.hpp" #include "oops/compressedOops.hpp" #include "oops/oopHandle.hpp" #include "utilities/bitMap.hpp" #include "utilities/exceptions.hpp" #include "utilities/growableArray.hpp" #include "utilities/hashTable.hpp" #include "utilities/macros.hpp" class MemRegion; #if INCLUDE_CDS_JAVA_HEAP class DumpedInternedStrings : public ResizeableHashTable { public: DumpedInternedStrings(unsigned size, unsigned max_size) : ResizeableHashTable(size, max_size) {} }; class AOTMappedHeapWriter : AllStatic { friend class HeapShared; friend class AOTMappedHeapLoader; // AOTMappedHeapWriter manipulates three types of addresses: // // "source" vs "buffered" vs "requested" // // (Note: the design and convention is the same as for the archiving of Metaspace objects. // See archiveBuilder.hpp.) // // - "source objects" are regular Java objects allocated during the execution // of "java -Xshare:dump". They can be used as regular oops. // // Between HeapShared::start_scanning_for_oops() and HeapShared::end_scanning_for_oops(), // we recursively search for the oops that need to be stored into the CDS archive. // These are entered into HeapShared::archived_object_cache(). // // - "buffered objects" are copies of the "source objects", and are stored in into // AOTMappedHeapWriter::_buffer, which is a GrowableArray that sits outside of // the valid heap range. Therefore we avoid using the addresses of these copies // as oops. They are usually called "buffered_addr" in the code (of the type "address"). // // The buffered objects are stored contiguously, possibly with interleaving fillers // to make sure no objects span across boundaries of MIN_GC_REGION_ALIGNMENT. // // - Each archived object has a "requested address" -- at run time, if the object // can be mapped at this address, we can avoid relocation. // // The requested address of an archived object is essentially its buffered_addr + delta, // where delta is (_requested_bottom - buffer_bottom()); // // The requested addresses of all archived objects are within [_requested_bottom, _requested_top). // See AOTMappedHeapWriter::set_requested_address_range() for more info. // ---------------------------------------------------------------------- public: static const intptr_t NOCOOPS_REQUESTED_BASE = 0x10000000; // The minimum region size of all collectors that are supported by CDS. // G1 heap region size can never be smaller than 1M. // Shenandoah heap region size can never be smaller than 256K. static constexpr int MIN_GC_REGION_ALIGNMENT = 256 * K; // The heap contents are required to be deterministic when dumping "old" CDS archives, in order // to support reproducible lib/server/classes*.jsa when building the JDK. static bool is_writing_deterministic_heap() { return _is_writing_deterministic_heap; } // The oop encoding used by the archived heap objects. static CompressedOops::Mode narrow_oop_mode(); static address narrow_oop_base(); static int narrow_oop_shift(); static const int INITIAL_TABLE_SIZE = 15889; // prime number static const int MAX_TABLE_SIZE = 1000000; private: class EmbeddedOopRelocator; struct NativePointerInfo { oop _src_obj; int _field_offset; }; static bool _is_writing_deterministic_heap; static GrowableArrayCHeap* _buffer; // The number of bytes that have written into _buffer (may be smaller than _buffer->length()). static size_t _buffer_used; // The heap root segments information. static HeapRootSegments _heap_root_segments; // The address range of the requested location of the archived heap objects. static address _requested_bottom; // The requested address of the lowest archived heap object static address _requested_top; // The exclusive end of the highest archived heap object static GrowableArrayCHeap* _native_pointers; static GrowableArrayCHeap* _source_objs; static DumpedInternedStrings *_dumped_interned_strings; // We sort _source_objs_order to minimize the number of bits in ptrmap and oopmap. // See comments near the body of AOTMappedHeapWriter::compare_objs_by_oop_fields(). // The objects will be written in the order of: //_source_objs->at(_source_objs_order->at(0)._index) // source_objs->at(_source_objs_order->at(1)._index) // source_objs->at(_source_objs_order->at(2)._index) // ... struct HeapObjOrder { int _index; // The location of this object in _source_objs int _rank; // A lower rank means the object will be written at a lower location. }; static GrowableArrayCHeap* _source_objs_order; typedef ResizeableHashTable BufferOffsetToSourceObjectTable; static BufferOffsetToSourceObjectTable* _buffer_offset_to_source_obj_table; static void allocate_buffer(); static void ensure_buffer_space(size_t min_bytes); // Both Java bytearray and GrowableArraty use int indices and lengths. Do a safe typecast with range check static int to_array_index(size_t i) { assert(i <= (size_t)max_jint, "must be"); return (int)i; } static int to_array_length(size_t n) { return to_array_index(n); } template static T offset_to_buffered_address(size_t offset) { return (T)(_buffer->adr_at(to_array_index(offset))); } static address buffer_bottom() { return offset_to_buffered_address
(0); } // The exclusive end of the last object that was copied into the buffer. static address buffer_top() { return buffer_bottom() + _buffer_used; } static bool in_buffer(address buffered_addr) { return (buffer_bottom() <= buffered_addr) && (buffered_addr < buffer_top()); } static size_t buffered_address_to_offset(address buffered_addr) { assert(in_buffer(buffered_addr), "sanity"); return buffered_addr - buffer_bottom(); } static void root_segment_at_put(objArrayOop segment, int index, oop root); static objArrayOop allocate_root_segment(size_t offset, int element_count); static void copy_roots_to_buffer(GrowableArrayCHeap* roots); static void copy_source_objs_to_buffer(GrowableArrayCHeap* roots); static size_t copy_one_source_obj_to_buffer(oop src_obj); static void maybe_fill_gc_region_gap(size_t required_byte_size); static size_t filler_array_byte_size(int length); static int filler_array_length(size_t fill_bytes); static HeapWord* init_filler_array_at_buffer_top(int array_length, size_t fill_bytes); static void set_requested_address_range(ArchiveMappedHeapInfo* info); static void mark_native_pointers(oop orig_obj); static void relocate_embedded_oops(GrowableArrayCHeap* roots, ArchiveMappedHeapInfo* info); static void compute_ptrmap(ArchiveMappedHeapInfo *info); static bool is_in_requested_range(oop o); static oop requested_obj_from_buffer_offset(size_t offset); static oop load_oop_from_buffer(oop* buffered_addr); static oop load_oop_from_buffer(narrowOop* buffered_addr); inline static void store_oop_in_buffer(oop* buffered_addr, oop requested_obj); inline static void store_oop_in_buffer(narrowOop* buffered_addr, oop requested_obj); template static oop load_source_oop_from_buffer(T* buffered_addr); template static void store_requested_oop_in_buffer(T* buffered_addr, oop request_oop); template static T* requested_addr_to_buffered_addr(T* p); template static void relocate_field_in_buffer(T* field_addr_in_buffer, oop source_referent, CHeapBitMap* oopmap); template static void mark_oop_pointer(T* buffered_addr, CHeapBitMap* oopmap); static void update_header_for_requested_obj(oop requested_obj, oop src_obj, Klass* src_klass); static int compare_objs_by_oop_fields(HeapObjOrder* a, HeapObjOrder* b); static void sort_source_objs(); public: static void init() NOT_CDS_JAVA_HEAP_RETURN; static void delete_tables_with_raw_oops(); static void add_source_obj(oop src_obj); static bool is_too_large_to_archive(size_t size); static bool is_too_large_to_archive(oop obj); static bool is_string_too_large_to_archive(oop string); static bool is_dumped_interned_string(oop o); static void add_to_dumped_interned_strings(oop string); static void write(GrowableArrayCHeap*, ArchiveMappedHeapInfo* heap_info); static address requested_address(); // requested address of the lowest achived heap object static size_t get_filler_size_at(address buffered_addr); static void mark_native_pointer(oop src_obj, int offset); static oop source_obj_to_requested_obj(oop src_obj); static oop buffered_addr_to_source_obj(address buffered_addr); static address buffered_addr_to_requested_addr(address buffered_addr); static Klass* real_klass_of_buffered_oop(address buffered_addr); static size_t size_of_buffered_oop(address buffered_addr); static AOTMapLogger::OopDataIterator* oop_iterator(ArchiveMappedHeapInfo* heap_info); }; #endif // INCLUDE_CDS_JAVA_HEAP #endif // SHARE_CDS_AOTMAPPEDHEAPWRITER_HPP