1 /* 2 * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "cds/archiveHeapWriter.hpp" 27 #include "cds/cdsConfig.hpp" 28 #include "cds/filemap.hpp" 29 #include "cds/heapShared.hpp" 30 #include "classfile/systemDictionary.hpp" 31 #include "gc/shared/collectedHeap.hpp" 32 #include "memory/iterator.inline.hpp" 33 #include "memory/oopFactory.hpp" 34 #include "memory/universe.hpp" 35 #include "oops/compressedOops.hpp" 36 #include "oops/oop.inline.hpp" 37 #include "oops/objArrayOop.inline.hpp" 38 #include "oops/oopHandle.inline.hpp" 39 #include "oops/typeArrayKlass.hpp" 40 #include "oops/typeArrayOop.hpp" 41 #include "runtime/java.hpp" 42 #include "runtime/mutexLocker.hpp" 43 #include "utilities/bitMap.inline.hpp" 44 #if INCLUDE_G1GC 45 #include "gc/g1/g1CollectedHeap.hpp" 46 #include "gc/g1/g1HeapRegion.hpp" 47 #endif 48 49 #if INCLUDE_CDS_JAVA_HEAP 50 51 GrowableArrayCHeap<u1, mtClassShared>* ArchiveHeapWriter::_buffer = nullptr; 52 53 // The following are offsets from buffer_bottom() 54 size_t ArchiveHeapWriter::_buffer_used; 55 size_t ArchiveHeapWriter::_heap_roots_offset; 56 57 size_t ArchiveHeapWriter::_heap_roots_word_size; 58 59 address ArchiveHeapWriter::_requested_bottom; 60 address ArchiveHeapWriter::_requested_top; 61 62 GrowableArrayCHeap<ArchiveHeapWriter::NativePointerInfo, mtClassShared>* ArchiveHeapWriter::_native_pointers; 63 GrowableArrayCHeap<oop, mtClassShared>* ArchiveHeapWriter::_source_objs; 64 GrowableArrayCHeap<ArchiveHeapWriter::HeapObjOrder, mtClassShared>* ArchiveHeapWriter::_source_objs_order; 65 66 ArchiveHeapWriter::BufferOffsetToSourceObjectTable* 67 ArchiveHeapWriter::_buffer_offset_to_source_obj_table = nullptr; 68 69 70 typedef ResourceHashtable< 71 size_t, // offset of a filler from ArchiveHeapWriter::buffer_bottom() 72 size_t, // size of this filler (in bytes) 73 127, // prime number 74 AnyObj::C_HEAP, 75 mtClassShared> FillersTable; 76 static FillersTable* _fillers; 77 static int _num_native_ptrs = 0; 78 79 void ArchiveHeapWriter::init() { 80 if (HeapShared::can_write()) { 81 Universe::heap()->collect(GCCause::_java_lang_system_gc); 82 83 _buffer_offset_to_source_obj_table = new BufferOffsetToSourceObjectTable(/*size (prime)*/36137, /*max size*/1 * M); 84 _fillers = new FillersTable(); 85 _requested_bottom = nullptr; 86 _requested_top = nullptr; 87 88 _native_pointers = new GrowableArrayCHeap<NativePointerInfo, mtClassShared>(2048); 89 _source_objs = new GrowableArrayCHeap<oop, mtClassShared>(10000); 90 91 guarantee(UseG1GC, "implementation limitation"); 92 guarantee(MIN_GC_REGION_ALIGNMENT <= G1HeapRegion::min_region_size_in_words() * HeapWordSize, "must be"); 93 } 94 } 95 96 void ArchiveHeapWriter::add_source_obj(oop src_obj) { 97 _source_objs->append(src_obj); 98 } 99 100 void ArchiveHeapWriter::write(GrowableArrayCHeap<oop, mtClassShared>* roots, 101 ArchiveHeapInfo* heap_info) { 102 assert(HeapShared::can_write(), "sanity"); 103 allocate_buffer(); 104 copy_source_objs_to_buffer(roots); 105 set_requested_address(heap_info); 106 relocate_embedded_oops(roots, heap_info); 107 } 108 109 bool ArchiveHeapWriter::is_too_large_to_archive(oop o) { 110 return is_too_large_to_archive(o->size()); 111 } 112 113 bool ArchiveHeapWriter::is_string_too_large_to_archive(oop string) { 114 typeArrayOop value = java_lang_String::value_no_keepalive(string); 115 return is_too_large_to_archive(value); 116 } 117 118 bool ArchiveHeapWriter::is_too_large_to_archive(size_t size) { 119 assert(size > 0, "no zero-size object"); 120 assert(size * HeapWordSize > size, "no overflow"); 121 static_assert(MIN_GC_REGION_ALIGNMENT > 0, "must be positive"); 122 123 size_t byte_size = size * HeapWordSize; 124 if (byte_size > size_t(MIN_GC_REGION_ALIGNMENT)) { 125 return true; 126 } else { 127 return false; 128 } 129 } 130 131 // Various lookup functions between source_obj, buffered_obj and requested_obj 132 bool ArchiveHeapWriter::is_in_requested_range(oop o) { 133 assert(_requested_bottom != nullptr, "do not call before _requested_bottom is initialized"); 134 address a = cast_from_oop<address>(o); 135 return (_requested_bottom <= a && a < _requested_top); 136 } 137 138 oop ArchiveHeapWriter::requested_obj_from_buffer_offset(size_t offset) { 139 oop req_obj = cast_to_oop(_requested_bottom + offset); 140 assert(is_in_requested_range(req_obj), "must be"); 141 return req_obj; 142 } 143 144 oop ArchiveHeapWriter::source_obj_to_requested_obj(oop src_obj) { 145 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 146 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 147 if (p != nullptr) { 148 return requested_obj_from_buffer_offset(p->buffer_offset()); 149 } else { 150 return nullptr; 151 } 152 } 153 154 oop ArchiveHeapWriter::buffered_addr_to_source_obj(address buffered_addr) { 155 oop* p = _buffer_offset_to_source_obj_table->get(buffered_address_to_offset(buffered_addr)); 156 if (p != nullptr) { 157 return *p; 158 } else { 159 return nullptr; 160 } 161 } 162 163 address ArchiveHeapWriter::buffered_addr_to_requested_addr(address buffered_addr) { 164 return _requested_bottom + buffered_address_to_offset(buffered_addr); 165 } 166 167 oop ArchiveHeapWriter::heap_roots_requested_address() { 168 return cast_to_oop(_requested_bottom + _heap_roots_offset); 169 } 170 171 address ArchiveHeapWriter::requested_address() { 172 assert(_buffer != nullptr, "must be initialized"); 173 return _requested_bottom; 174 } 175 176 void ArchiveHeapWriter::allocate_buffer() { 177 int initial_buffer_size = 100000; 178 _buffer = new GrowableArrayCHeap<u1, mtClassShared>(initial_buffer_size); 179 _buffer_used = 0; 180 ensure_buffer_space(1); // so that buffer_bottom() works 181 } 182 183 void ArchiveHeapWriter::ensure_buffer_space(size_t min_bytes) { 184 // We usually have very small heaps. If we get a huge one it's probably caused by a bug. 185 guarantee(min_bytes <= max_jint, "we dont support archiving more than 2G of objects"); 186 _buffer->at_grow(to_array_index(min_bytes)); 187 } 188 189 void ArchiveHeapWriter::copy_roots_to_buffer(GrowableArrayCHeap<oop, mtClassShared>* roots) { 190 Klass* k = Universe::objectArrayKlass(); // already relocated to point to archived klass 191 int length = roots->length(); 192 _heap_roots_word_size = objArrayOopDesc::object_size(length); 193 size_t byte_size = _heap_roots_word_size * HeapWordSize; 194 if (byte_size >= MIN_GC_REGION_ALIGNMENT) { 195 log_error(cds, heap)("roots array is too large. Please reduce the number of classes"); 196 vm_exit(1); 197 } 198 199 maybe_fill_gc_region_gap(byte_size); 200 201 size_t new_used = _buffer_used + byte_size; 202 ensure_buffer_space(new_used); 203 204 HeapWord* mem = offset_to_buffered_address<HeapWord*>(_buffer_used); 205 memset(mem, 0, byte_size); 206 { 207 // This is copied from MemAllocator::finish 208 if (UseCompactObjectHeaders) { 209 narrowKlass nk = ArchiveBuilder::current()->get_requested_narrow_klass(k); 210 oopDesc::release_set_mark(mem, markWord::prototype().set_narrow_klass(nk)); 211 } else { 212 oopDesc::set_mark(mem, markWord::prototype()); 213 oopDesc::release_set_klass(mem, k); 214 } 215 } 216 { 217 // This is copied from ObjArrayAllocator::initialize 218 arrayOopDesc::set_length(mem, length); 219 } 220 221 objArrayOop arrayOop = objArrayOop(cast_to_oop(mem)); 222 for (int i = 0; i < length; i++) { 223 // Do not use arrayOop->obj_at_put(i, o) as arrayOop is outside of the real heap! 224 oop o = roots->at(i); 225 if (UseCompressedOops) { 226 * arrayOop->obj_at_addr<narrowOop>(i) = CompressedOops::encode(o); 227 } else { 228 * arrayOop->obj_at_addr<oop>(i) = o; 229 } 230 } 231 log_info(cds, heap)("archived obj roots[%d] = " SIZE_FORMAT " bytes, klass = %p, obj = %p", length, byte_size, k, mem); 232 233 _heap_roots_offset = _buffer_used; 234 _buffer_used = new_used; 235 } 236 237 static int oop_sorting_rank(oop o) { 238 bool has_oop_ptr, has_native_ptr; 239 HeapShared::get_pointer_info(o, has_oop_ptr, has_native_ptr); 240 241 if (!has_oop_ptr) { 242 if (!has_native_ptr) { 243 return 0; 244 } else { 245 return 1; 246 } 247 } else { 248 if (has_native_ptr) { 249 return 2; 250 } else { 251 return 3; 252 } 253 } 254 } 255 256 // The goal is to sort the objects in increasing order of: 257 // - objects that have no pointers 258 // - objects that have only native pointers 259 // - objects that have both native and oop pointers 260 // - objects that have only oop pointers 261 int ArchiveHeapWriter::compare_objs_by_oop_fields(HeapObjOrder* a, HeapObjOrder* b) { 262 int rank_a = a->_rank; 263 int rank_b = b->_rank; 264 265 if (rank_a != rank_b) { 266 return rank_a - rank_b; 267 } else { 268 // If they are the same rank, sort them by their position in the _source_objs array 269 return a->_index - b->_index; 270 } 271 } 272 273 void ArchiveHeapWriter::sort_source_objs() { 274 log_info(cds)("sorting heap objects"); 275 int len = _source_objs->length(); 276 _source_objs_order = new GrowableArrayCHeap<HeapObjOrder, mtClassShared>(len); 277 278 for (int i = 0; i < len; i++) { 279 oop o = _source_objs->at(i); 280 int rank = oop_sorting_rank(o); 281 HeapObjOrder os = {i, rank}; 282 _source_objs_order->append(os); 283 } 284 log_info(cds)("computed ranks"); 285 _source_objs_order->sort(compare_objs_by_oop_fields); 286 log_info(cds)("sorting heap objects done"); 287 } 288 289 void ArchiveHeapWriter::copy_source_objs_to_buffer(GrowableArrayCHeap<oop, mtClassShared>* roots) { 290 sort_source_objs(); 291 for (int i = 0; i < _source_objs_order->length(); i++) { 292 int src_obj_index = _source_objs_order->at(i)._index; 293 oop src_obj = _source_objs->at(src_obj_index); 294 HeapShared::CachedOopInfo* info = HeapShared::archived_object_cache()->get(src_obj); 295 assert(info != nullptr, "must be"); 296 size_t buffer_offset = copy_one_source_obj_to_buffer(src_obj); 297 info->set_buffer_offset(buffer_offset); 298 299 _buffer_offset_to_source_obj_table->put_when_absent(buffer_offset, src_obj); 300 _buffer_offset_to_source_obj_table->maybe_grow(); 301 } 302 303 copy_roots_to_buffer(roots); 304 305 log_info(cds)("Size of heap region = " SIZE_FORMAT " bytes, %d objects, %d roots, %d native ptrs", 306 _buffer_used, _source_objs->length() + 1, roots->length(), _num_native_ptrs); 307 } 308 309 size_t ArchiveHeapWriter::filler_array_byte_size(int length) { 310 size_t byte_size = objArrayOopDesc::object_size(length) * HeapWordSize; 311 return byte_size; 312 } 313 314 int ArchiveHeapWriter::filler_array_length(size_t fill_bytes) { 315 assert(is_object_aligned(fill_bytes), "must be"); 316 size_t elemSize = (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop)); 317 318 int initial_length = to_array_length(fill_bytes / elemSize); 319 for (int length = initial_length; length >= 0; length --) { 320 size_t array_byte_size = filler_array_byte_size(length); 321 if (array_byte_size == fill_bytes) { 322 return length; 323 } 324 } 325 326 ShouldNotReachHere(); 327 return -1; 328 } 329 330 HeapWord* ArchiveHeapWriter::init_filler_array_at_buffer_top(int array_length, size_t fill_bytes) { 331 assert(UseCompressedClassPointers, "Archived heap only supported for compressed klasses"); 332 Klass* oak = Universe::objectArrayKlass(); // already relocated to point to archived klass 333 HeapWord* mem = offset_to_buffered_address<HeapWord*>(_buffer_used); 334 memset(mem, 0, fill_bytes); 335 narrowKlass nk = ArchiveBuilder::current()->get_requested_narrow_klass(oak); 336 if (UseCompactObjectHeaders) { 337 oopDesc::release_set_mark(mem, markWord::prototype().set_narrow_klass(nk)); 338 } else { 339 oopDesc::set_mark(mem, markWord::prototype()); 340 cast_to_oop(mem)->set_narrow_klass(nk); 341 } 342 arrayOopDesc::set_length(mem, array_length); 343 return mem; 344 } 345 346 void ArchiveHeapWriter::maybe_fill_gc_region_gap(size_t required_byte_size) { 347 // We fill only with arrays (so we don't need to use a single HeapWord filler if the 348 // leftover space is smaller than a zero-sized array object). Therefore, we need to 349 // make sure there's enough space of min_filler_byte_size in the current region after 350 // required_byte_size has been allocated. If not, fill the remainder of the current 351 // region. 352 size_t min_filler_byte_size = filler_array_byte_size(0); 353 size_t new_used = _buffer_used + required_byte_size + min_filler_byte_size; 354 355 const size_t cur_min_region_bottom = align_down(_buffer_used, MIN_GC_REGION_ALIGNMENT); 356 const size_t next_min_region_bottom = align_down(new_used, MIN_GC_REGION_ALIGNMENT); 357 358 if (cur_min_region_bottom != next_min_region_bottom) { 359 // Make sure that no objects span across MIN_GC_REGION_ALIGNMENT. This way 360 // we can map the region in any region-based collector. 361 assert(next_min_region_bottom > cur_min_region_bottom, "must be"); 362 assert(next_min_region_bottom - cur_min_region_bottom == MIN_GC_REGION_ALIGNMENT, 363 "no buffered object can be larger than %d bytes", MIN_GC_REGION_ALIGNMENT); 364 365 const size_t filler_end = next_min_region_bottom; 366 const size_t fill_bytes = filler_end - _buffer_used; 367 assert(fill_bytes > 0, "must be"); 368 ensure_buffer_space(filler_end); 369 370 int array_length = filler_array_length(fill_bytes); 371 log_info(cds, heap)("Inserting filler obj array of %d elements (" SIZE_FORMAT " bytes total) @ buffer offset " SIZE_FORMAT, 372 array_length, fill_bytes, _buffer_used); 373 HeapWord* filler = init_filler_array_at_buffer_top(array_length, fill_bytes); 374 _buffer_used = filler_end; 375 _fillers->put(buffered_address_to_offset((address)filler), fill_bytes); 376 } 377 } 378 379 size_t ArchiveHeapWriter::get_filler_size_at(address buffered_addr) { 380 size_t* p = _fillers->get(buffered_address_to_offset(buffered_addr)); 381 if (p != nullptr) { 382 assert(*p > 0, "filler must be larger than zero bytes"); 383 return *p; 384 } else { 385 return 0; // buffered_addr is not a filler 386 } 387 } 388 389 template <typename T> 390 void update_buffered_object_field(address buffered_obj, int field_offset, T value) { 391 T* field_addr = cast_to_oop(buffered_obj)->field_addr<T>(field_offset); 392 *field_addr = value; 393 } 394 395 size_t ArchiveHeapWriter::copy_one_source_obj_to_buffer(oop src_obj) { 396 assert(!is_too_large_to_archive(src_obj), "already checked"); 397 size_t byte_size = src_obj->size() * HeapWordSize; 398 assert(byte_size > 0, "no zero-size objects"); 399 400 // For region-based collectors such as G1, the archive heap may be mapped into 401 // multiple regions. We need to make sure that we don't have an object that can possible 402 // span across two regions. 403 maybe_fill_gc_region_gap(byte_size); 404 405 size_t new_used = _buffer_used + byte_size; 406 assert(new_used > _buffer_used, "no wrap around"); 407 408 size_t cur_min_region_bottom = align_down(_buffer_used, MIN_GC_REGION_ALIGNMENT); 409 size_t next_min_region_bottom = align_down(new_used, MIN_GC_REGION_ALIGNMENT); 410 assert(cur_min_region_bottom == next_min_region_bottom, "no object should cross minimal GC region boundaries"); 411 412 ensure_buffer_space(new_used); 413 414 address from = cast_from_oop<address>(src_obj); 415 address to = offset_to_buffered_address<address>(_buffer_used); 416 assert(is_object_aligned(_buffer_used), "sanity"); 417 assert(is_object_aligned(byte_size), "sanity"); 418 memcpy(to, from, byte_size); 419 420 // These native pointers will be restored explicitly at run time. 421 if (java_lang_Module::is_instance(src_obj)) { 422 update_buffered_object_field<ModuleEntry*>(to, java_lang_Module::module_entry_offset(), nullptr); 423 } else if (java_lang_ClassLoader::is_instance(src_obj)) { 424 #ifdef ASSERT 425 // We only archive these loaders 426 if (src_obj != SystemDictionary::java_platform_loader() && 427 src_obj != SystemDictionary::java_system_loader()) { 428 assert(src_obj->klass()->name()->equals("jdk/internal/loader/ClassLoaders$BootClassLoader"), "must be"); 429 } 430 #endif 431 update_buffered_object_field<ClassLoaderData*>(to, java_lang_ClassLoader::loader_data_offset(), nullptr); 432 } 433 434 size_t buffered_obj_offset = _buffer_used; 435 _buffer_used = new_used; 436 437 return buffered_obj_offset; 438 } 439 440 void ArchiveHeapWriter::set_requested_address(ArchiveHeapInfo* info) { 441 assert(!info->is_used(), "only set once"); 442 assert(UseG1GC, "must be"); 443 address heap_end = (address)G1CollectedHeap::heap()->reserved().end(); 444 log_info(cds, heap)("Heap end = %p", heap_end); 445 446 size_t heap_region_byte_size = _buffer_used; 447 assert(heap_region_byte_size > 0, "must archived at least one object!"); 448 449 450 if (UseCompressedOops) { 451 _requested_bottom = align_down(heap_end - heap_region_byte_size, G1HeapRegion::GrainBytes); 452 } else { 453 // We always write the objects as if the heap started at this address. This 454 // makes the contents of the archive heap deterministic. 455 // 456 // Note that at runtime, the heap address is selected by the OS, so the archive 457 // heap will not be mapped at 0x10000000, and the contents need to be patched. 458 _requested_bottom = (address)NOCOOPS_REQUESTED_BASE; 459 } 460 461 assert(is_aligned(_requested_bottom, G1HeapRegion::GrainBytes), "sanity"); 462 463 _requested_top = _requested_bottom + _buffer_used; 464 465 info->set_buffer_region(MemRegion(offset_to_buffered_address<HeapWord*>(0), 466 offset_to_buffered_address<HeapWord*>(_buffer_used))); 467 info->set_heap_roots_offset(_heap_roots_offset); 468 } 469 470 // Oop relocation 471 472 template <typename T> T* ArchiveHeapWriter::requested_addr_to_buffered_addr(T* p) { 473 assert(is_in_requested_range(cast_to_oop(p)), "must be"); 474 475 address addr = address(p); 476 assert(addr >= _requested_bottom, "must be"); 477 size_t offset = addr - _requested_bottom; 478 return offset_to_buffered_address<T*>(offset); 479 } 480 481 template <typename T> oop ArchiveHeapWriter::load_source_oop_from_buffer(T* buffered_addr) { 482 oop o = load_oop_from_buffer(buffered_addr); 483 assert(!in_buffer(cast_from_oop<address>(o)), "must point to source oop"); 484 return o; 485 } 486 487 template <typename T> void ArchiveHeapWriter::store_requested_oop_in_buffer(T* buffered_addr, 488 oop request_oop) { 489 assert(is_in_requested_range(request_oop), "must be"); 490 store_oop_in_buffer(buffered_addr, request_oop); 491 } 492 493 inline void ArchiveHeapWriter::store_oop_in_buffer(oop* buffered_addr, oop requested_obj) { 494 *buffered_addr = requested_obj; 495 } 496 497 inline void ArchiveHeapWriter::store_oop_in_buffer(narrowOop* buffered_addr, oop requested_obj) { 498 narrowOop val = CompressedOops::encode_not_null(requested_obj); 499 *buffered_addr = val; 500 } 501 502 oop ArchiveHeapWriter::load_oop_from_buffer(oop* buffered_addr) { 503 return *buffered_addr; 504 } 505 506 oop ArchiveHeapWriter::load_oop_from_buffer(narrowOop* buffered_addr) { 507 return CompressedOops::decode(*buffered_addr); 508 } 509 510 template <typename T> void ArchiveHeapWriter::relocate_field_in_buffer(T* field_addr_in_buffer, CHeapBitMap* oopmap) { 511 oop source_referent = load_source_oop_from_buffer<T>(field_addr_in_buffer); 512 if (!CompressedOops::is_null(source_referent)) { 513 oop request_referent = source_obj_to_requested_obj(source_referent); 514 store_requested_oop_in_buffer<T>(field_addr_in_buffer, request_referent); 515 mark_oop_pointer<T>(field_addr_in_buffer, oopmap); 516 } 517 } 518 519 template <typename T> void ArchiveHeapWriter::mark_oop_pointer(T* buffered_addr, CHeapBitMap* oopmap) { 520 T* request_p = (T*)(buffered_addr_to_requested_addr((address)buffered_addr)); 521 address requested_region_bottom; 522 523 assert(request_p >= (T*)_requested_bottom, "sanity"); 524 assert(request_p < (T*)_requested_top, "sanity"); 525 requested_region_bottom = _requested_bottom; 526 527 // Mark the pointer in the oopmap 528 T* region_bottom = (T*)requested_region_bottom; 529 assert(request_p >= region_bottom, "must be"); 530 BitMap::idx_t idx = request_p - region_bottom; 531 assert(idx < oopmap->size(), "overflow"); 532 oopmap->set_bit(idx); 533 } 534 535 void ArchiveHeapWriter::update_header_for_requested_obj(oop requested_obj, oop src_obj, Klass* src_klass) { 536 assert(UseCompressedClassPointers, "Archived heap only supported for compressed klasses"); 537 narrowKlass nk = ArchiveBuilder::current()->get_requested_narrow_klass(src_klass); 538 address buffered_addr = requested_addr_to_buffered_addr(cast_from_oop<address>(requested_obj)); 539 540 oop fake_oop = cast_to_oop(buffered_addr); 541 if (UseCompactObjectHeaders) { 542 fake_oop->set_mark(markWord::prototype().set_narrow_klass(nk)); 543 } else { 544 fake_oop->set_narrow_klass(nk); 545 } 546 547 // We need to retain the identity_hash, because it may have been used by some hashtables 548 // in the shared heap. 549 if (src_obj != nullptr && !src_obj->fast_no_hash_check()) { 550 intptr_t src_hash = src_obj->identity_hash(); 551 if (UseCompactObjectHeaders) { 552 fake_oop->set_mark(markWord::prototype().set_narrow_klass(nk).copy_set_hash(src_hash)); 553 } else { 554 fake_oop->set_mark(markWord::prototype().copy_set_hash(src_hash)); 555 } 556 assert(fake_oop->mark().is_unlocked(), "sanity"); 557 558 DEBUG_ONLY(intptr_t archived_hash = fake_oop->identity_hash()); 559 assert(src_hash == archived_hash, "Different hash codes: original " INTPTR_FORMAT ", archived " INTPTR_FORMAT, src_hash, archived_hash); 560 } 561 } 562 563 // Relocate an element in the buffered copy of HeapShared::roots() 564 template <typename T> void ArchiveHeapWriter::relocate_root_at(oop requested_roots, int index, CHeapBitMap* oopmap) { 565 size_t offset = (size_t)((objArrayOop)requested_roots)->obj_at_offset<T>(index); 566 relocate_field_in_buffer<T>((T*)(buffered_heap_roots_addr() + offset), oopmap); 567 } 568 569 class ArchiveHeapWriter::EmbeddedOopRelocator: public BasicOopIterateClosure { 570 oop _src_obj; 571 address _buffered_obj; 572 CHeapBitMap* _oopmap; 573 574 public: 575 EmbeddedOopRelocator(oop src_obj, address buffered_obj, CHeapBitMap* oopmap) : 576 _src_obj(src_obj), _buffered_obj(buffered_obj), _oopmap(oopmap) {} 577 578 void do_oop(narrowOop *p) { EmbeddedOopRelocator::do_oop_work(p); } 579 void do_oop( oop *p) { EmbeddedOopRelocator::do_oop_work(p); } 580 581 private: 582 template <class T> void do_oop_work(T *p) { 583 size_t field_offset = pointer_delta(p, _src_obj, sizeof(char)); 584 ArchiveHeapWriter::relocate_field_in_buffer<T>((T*)(_buffered_obj + field_offset), _oopmap); 585 } 586 }; 587 588 static void log_bitmap_usage(const char* which, BitMap* bitmap, size_t total_bits) { 589 // The whole heap is covered by total_bits, but there are only non-zero bits within [start ... end). 590 size_t start = bitmap->find_first_set_bit(0); 591 size_t end = bitmap->size(); 592 log_info(cds)("%s = " SIZE_FORMAT_W(7) " ... " SIZE_FORMAT_W(7) " (%3zu%% ... %3zu%% = %3zu%%)", which, 593 start, end, 594 start * 100 / total_bits, 595 end * 100 / total_bits, 596 (end - start) * 100 / total_bits); 597 } 598 599 // Update all oop fields embedded in the buffered objects 600 void ArchiveHeapWriter::relocate_embedded_oops(GrowableArrayCHeap<oop, mtClassShared>* roots, 601 ArchiveHeapInfo* heap_info) { 602 size_t oopmap_unit = (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop)); 603 size_t heap_region_byte_size = _buffer_used; 604 heap_info->oopmap()->resize(heap_region_byte_size / oopmap_unit); 605 606 for (int i = 0; i < _source_objs_order->length(); i++) { 607 int src_obj_index = _source_objs_order->at(i)._index; 608 oop src_obj = _source_objs->at(src_obj_index); 609 HeapShared::CachedOopInfo* info = HeapShared::archived_object_cache()->get(src_obj); 610 assert(info != nullptr, "must be"); 611 oop requested_obj = requested_obj_from_buffer_offset(info->buffer_offset()); 612 update_header_for_requested_obj(requested_obj, src_obj, src_obj->klass()); 613 address buffered_obj = offset_to_buffered_address<address>(info->buffer_offset()); 614 EmbeddedOopRelocator relocator(src_obj, buffered_obj, heap_info->oopmap()); 615 src_obj->oop_iterate(&relocator); 616 }; 617 618 // Relocate HeapShared::roots(), which is created in copy_roots_to_buffer() and 619 // doesn't have a corresponding src_obj, so we can't use EmbeddedOopRelocator on it. 620 oop requested_roots = requested_obj_from_buffer_offset(_heap_roots_offset); 621 update_header_for_requested_obj(requested_roots, nullptr, Universe::objectArrayKlass()); 622 int length = roots != nullptr ? roots->length() : 0; 623 for (int i = 0; i < length; i++) { 624 if (UseCompressedOops) { 625 relocate_root_at<narrowOop>(requested_roots, i, heap_info->oopmap()); 626 } else { 627 relocate_root_at<oop>(requested_roots, i, heap_info->oopmap()); 628 } 629 } 630 631 compute_ptrmap(heap_info); 632 633 size_t total_bytes = (size_t)_buffer->length(); 634 log_bitmap_usage("oopmap", heap_info->oopmap(), total_bytes / (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop))); 635 log_bitmap_usage("ptrmap", heap_info->ptrmap(), total_bytes / sizeof(address)); 636 } 637 638 void ArchiveHeapWriter::mark_native_pointer(oop src_obj, int field_offset) { 639 Metadata* ptr = src_obj->metadata_field_acquire(field_offset); 640 if (ptr != nullptr) { 641 NativePointerInfo info; 642 info._src_obj = src_obj; 643 info._field_offset = field_offset; 644 _native_pointers->append(info); 645 HeapShared::set_has_native_pointers(src_obj); 646 _num_native_ptrs ++; 647 } 648 } 649 650 // Do we have a jlong/jint field that's actually a pointer to a MetaspaceObj? 651 bool ArchiveHeapWriter::is_marked_as_native_pointer(ArchiveHeapInfo* heap_info, oop src_obj, int field_offset) { 652 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 653 assert(p != nullptr, "must be"); 654 655 // requested_field_addr = the address of this field in the requested space 656 oop requested_obj = requested_obj_from_buffer_offset(p->buffer_offset()); 657 Metadata** requested_field_addr = (Metadata**)(cast_from_oop<address>(requested_obj) + field_offset); 658 assert((Metadata**)_requested_bottom <= requested_field_addr && requested_field_addr < (Metadata**) _requested_top, "range check"); 659 660 BitMap::idx_t idx = requested_field_addr - (Metadata**) _requested_bottom; 661 // Leading zeros have been removed so some addresses may not be in the ptrmap 662 size_t start_pos = FileMapInfo::current_info()->heap_ptrmap_start_pos(); 663 if (idx < start_pos) { 664 return false; 665 } else { 666 idx -= start_pos; 667 } 668 return (idx < heap_info->ptrmap()->size()) && (heap_info->ptrmap()->at(idx) == true); 669 } 670 671 void ArchiveHeapWriter::compute_ptrmap(ArchiveHeapInfo* heap_info) { 672 int num_non_null_ptrs = 0; 673 Metadata** bottom = (Metadata**) _requested_bottom; 674 Metadata** top = (Metadata**) _requested_top; // exclusive 675 heap_info->ptrmap()->resize(top - bottom); 676 677 BitMap::idx_t max_idx = 32; // paranoid - don't make it too small 678 for (int i = 0; i < _native_pointers->length(); i++) { 679 NativePointerInfo info = _native_pointers->at(i); 680 oop src_obj = info._src_obj; 681 int field_offset = info._field_offset; 682 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 683 // requested_field_addr = the address of this field in the requested space 684 oop requested_obj = requested_obj_from_buffer_offset(p->buffer_offset()); 685 Metadata** requested_field_addr = (Metadata**)(cast_from_oop<address>(requested_obj) + field_offset); 686 assert(bottom <= requested_field_addr && requested_field_addr < top, "range check"); 687 688 // Mark this field in the bitmap 689 BitMap::idx_t idx = requested_field_addr - bottom; 690 heap_info->ptrmap()->set_bit(idx); 691 num_non_null_ptrs ++; 692 max_idx = MAX2(max_idx, idx); 693 694 // Set the native pointer to the requested address of the metadata (at runtime, the metadata will have 695 // this address if the RO/RW regions are mapped at the default location). 696 697 Metadata** buffered_field_addr = requested_addr_to_buffered_addr(requested_field_addr); 698 Metadata* native_ptr = *buffered_field_addr; 699 assert(native_ptr != nullptr, "sanity"); 700 701 address buffered_native_ptr = ArchiveBuilder::current()->get_buffered_addr((address)native_ptr); 702 address requested_native_ptr = ArchiveBuilder::current()->to_requested(buffered_native_ptr); 703 *buffered_field_addr = (Metadata*)requested_native_ptr; 704 } 705 706 heap_info->ptrmap()->resize(max_idx + 1); 707 log_info(cds, heap)("calculate_ptrmap: marked %d non-null native pointers for heap region (" SIZE_FORMAT " bits)", 708 num_non_null_ptrs, size_t(heap_info->ptrmap()->size())); 709 } 710 711 #endif // INCLUDE_CDS_JAVA_HEAP --- EOF ---