1 /* 2 * Copyright (c) 2023, 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 "cds/regeneratedClasses.hpp" 31 #include "classfile/javaClasses.hpp" 32 #include "classfile/systemDictionary.hpp" 33 #include "gc/shared/collectedHeap.hpp" 34 #include "memory/iterator.inline.hpp" 35 #include "memory/oopFactory.hpp" 36 #include "memory/universe.hpp" 37 #include "oops/compressedOops.hpp" 38 #include "oops/objArrayOop.inline.hpp" 39 #include "oops/oop.inline.hpp" 40 #include "oops/oopHandle.inline.hpp" 41 #include "oops/typeArrayKlass.hpp" 42 #include "oops/typeArrayOop.hpp" 43 #include "runtime/java.hpp" 44 #include "runtime/mutexLocker.hpp" 45 #include "utilities/bitMap.inline.hpp" 46 #if INCLUDE_G1GC 47 #include "gc/g1/g1CollectedHeap.hpp" 48 #include "gc/g1/g1HeapRegion.hpp" 49 #endif 50 51 #if INCLUDE_CDS_JAVA_HEAP 52 53 GrowableArrayCHeap<u1, mtClassShared>* ArchiveHeapWriter::_buffer = nullptr; 54 55 // The following are offsets from buffer_bottom() 56 size_t ArchiveHeapWriter::_buffer_used; 57 58 // Heap root segments 59 HeapRootSegments ArchiveHeapWriter::_heap_root_segments; 60 61 address ArchiveHeapWriter::_requested_bottom; 62 address ArchiveHeapWriter::_requested_top; 63 64 static size_t _num_strings = 0; 65 static size_t _string_bytes = 0; 66 static size_t _num_packages = 0; 67 static size_t _num_protection_domains = 0; 68 69 GrowableArrayCHeap<ArchiveHeapWriter::NativePointerInfo, mtClassShared>* ArchiveHeapWriter::_native_pointers; 70 GrowableArrayCHeap<oop, mtClassShared>* ArchiveHeapWriter::_source_objs; 71 GrowableArrayCHeap<ArchiveHeapWriter::HeapObjOrder, mtClassShared>* ArchiveHeapWriter::_source_objs_order; 72 73 ArchiveHeapWriter::BufferOffsetToSourceObjectTable* 74 ArchiveHeapWriter::_buffer_offset_to_source_obj_table = nullptr; 75 76 77 typedef ResourceHashtable< 78 size_t, // offset of a filler from ArchiveHeapWriter::buffer_bottom() 79 size_t, // size of this filler (in bytes) 80 127, // prime number 81 AnyObj::C_HEAP, 82 mtClassShared> FillersTable; 83 static FillersTable* _fillers; 84 static int _num_native_ptrs = 0; 85 86 void ArchiveHeapWriter::init() { 87 if (HeapShared::can_write()) { 88 Universe::heap()->collect(GCCause::_java_lang_system_gc); 89 90 _buffer_offset_to_source_obj_table = new BufferOffsetToSourceObjectTable(/*size (prime)*/36137, /*max size*/1 * M); 91 _fillers = new FillersTable(); 92 _requested_bottom = nullptr; 93 _requested_top = nullptr; 94 95 _native_pointers = new GrowableArrayCHeap<NativePointerInfo, mtClassShared>(2048); 96 _source_objs = new GrowableArrayCHeap<oop, mtClassShared>(10000); 97 98 guarantee(MIN_GC_REGION_ALIGNMENT <= G1HeapRegion::min_region_size_in_words() * HeapWordSize, "must be"); 99 } 100 } 101 102 void ArchiveHeapWriter::add_source_obj(oop src_obj) { 103 _source_objs->append(src_obj); 104 } 105 106 void ArchiveHeapWriter::write(GrowableArrayCHeap<oop, mtClassShared>* roots, 107 ArchiveHeapInfo* heap_info) { 108 assert(HeapShared::can_write(), "sanity"); 109 allocate_buffer(); 110 copy_source_objs_to_buffer(roots); 111 set_requested_address(heap_info); 112 relocate_embedded_oops(roots, heap_info); 113 } 114 115 bool ArchiveHeapWriter::is_too_large_to_archive(oop o) { 116 return is_too_large_to_archive(o->size()); 117 } 118 119 bool ArchiveHeapWriter::is_string_too_large_to_archive(oop string) { 120 typeArrayOop value = java_lang_String::value_no_keepalive(string); 121 return is_too_large_to_archive(value); 122 } 123 124 bool ArchiveHeapWriter::is_too_large_to_archive(size_t size) { 125 assert(size > 0, "no zero-size object"); 126 assert(size * HeapWordSize > size, "no overflow"); 127 static_assert(MIN_GC_REGION_ALIGNMENT > 0, "must be positive"); 128 129 size_t byte_size = size * HeapWordSize; 130 if (byte_size > size_t(MIN_GC_REGION_ALIGNMENT)) { 131 return true; 132 } else { 133 return false; 134 } 135 } 136 137 // Various lookup functions between source_obj, buffered_obj and requested_obj 138 bool ArchiveHeapWriter::is_in_requested_range(oop o) { 139 assert(_requested_bottom != nullptr, "do not call before _requested_bottom is initialized"); 140 address a = cast_from_oop<address>(o); 141 return (_requested_bottom <= a && a < _requested_top); 142 } 143 144 oop ArchiveHeapWriter::requested_obj_from_buffer_offset(size_t offset) { 145 oop req_obj = cast_to_oop(_requested_bottom + offset); 146 assert(is_in_requested_range(req_obj), "must be"); 147 return req_obj; 148 } 149 150 oop ArchiveHeapWriter::source_obj_to_requested_obj(oop src_obj) { 151 assert(CDSConfig::is_dumping_heap(), "dump-time only"); 152 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 153 if (p != nullptr) { 154 return requested_obj_from_buffer_offset(p->buffer_offset()); 155 } else { 156 return nullptr; 157 } 158 } 159 160 oop ArchiveHeapWriter::buffered_addr_to_source_obj(address buffered_addr) { 161 oop* p = _buffer_offset_to_source_obj_table->get(buffered_address_to_offset(buffered_addr)); 162 if (p != nullptr) { 163 return *p; 164 } else { 165 return nullptr; 166 } 167 } 168 169 address ArchiveHeapWriter::buffered_addr_to_requested_addr(address buffered_addr) { 170 return _requested_bottom + buffered_address_to_offset(buffered_addr); 171 } 172 173 address ArchiveHeapWriter::requested_address() { 174 assert(_buffer != nullptr, "must be initialized"); 175 return _requested_bottom; 176 } 177 178 void ArchiveHeapWriter::allocate_buffer() { 179 int initial_buffer_size = 100000; 180 _buffer = new GrowableArrayCHeap<u1, mtClassShared>(initial_buffer_size); 181 _buffer_used = 0; 182 ensure_buffer_space(1); // so that buffer_bottom() works 183 } 184 185 void ArchiveHeapWriter::ensure_buffer_space(size_t min_bytes) { 186 // We usually have very small heaps. If we get a huge one it's probably caused by a bug. 187 guarantee(min_bytes <= max_jint, "we dont support archiving more than 2G of objects"); 188 _buffer->at_grow(to_array_index(min_bytes)); 189 } 190 191 objArrayOop ArchiveHeapWriter::allocate_root_segment(size_t offset, int element_count) { 192 HeapWord* mem = offset_to_buffered_address<HeapWord *>(offset); 193 memset(mem, 0, objArrayOopDesc::object_size(element_count)); 194 195 // The initialization code is copied from MemAllocator::finish and ObjArrayAllocator::initialize. 196 if (UseCompactObjectHeaders) { 197 oopDesc::release_set_mark(mem, Universe::objectArrayKlass()->prototype_header()); 198 } else { 199 oopDesc::set_mark(mem, markWord::prototype()); 200 oopDesc::release_set_klass(mem, Universe::objectArrayKlass()); 201 } 202 arrayOopDesc::set_length(mem, element_count); 203 return objArrayOop(cast_to_oop(mem)); 204 } 205 206 void ArchiveHeapWriter::root_segment_at_put(objArrayOop segment, int index, oop root) { 207 // Do not use arrayOop->obj_at_put(i, o) as arrayOop is outside the real heap! 208 if (UseCompressedOops) { 209 *segment->obj_at_addr<narrowOop>(index) = CompressedOops::encode(root); 210 } else { 211 *segment->obj_at_addr<oop>(index) = root; 212 } 213 } 214 215 void ArchiveHeapWriter::copy_roots_to_buffer(GrowableArrayCHeap<oop, mtClassShared>* roots) { 216 // Depending on the number of classes we are archiving, a single roots array may be 217 // larger than MIN_GC_REGION_ALIGNMENT. Roots are allocated first in the buffer, which 218 // allows us to chop the large array into a series of "segments". Current layout 219 // starts with zero or more segments exactly fitting MIN_GC_REGION_ALIGNMENT, and end 220 // with a single segment that may be smaller than MIN_GC_REGION_ALIGNMENT. 221 // This is simple and efficient. We do not need filler objects anywhere between the segments, 222 // or immediately after the last segment. This allows starting the object dump immediately 223 // after the roots. 224 225 assert((_buffer_used % MIN_GC_REGION_ALIGNMENT) == 0, 226 "Pre-condition: Roots start at aligned boundary: " SIZE_FORMAT, _buffer_used); 227 228 int max_elem_count = ((MIN_GC_REGION_ALIGNMENT - arrayOopDesc::header_size_in_bytes()) / heapOopSize); 229 assert(objArrayOopDesc::object_size(max_elem_count)*HeapWordSize == MIN_GC_REGION_ALIGNMENT, 230 "Should match exactly"); 231 232 HeapRootSegments segments(_buffer_used, 233 roots->length(), 234 MIN_GC_REGION_ALIGNMENT, 235 max_elem_count); 236 237 int root_index = 0; 238 for (size_t seg_idx = 0; seg_idx < segments.count(); seg_idx++) { 239 int size_elems = segments.size_in_elems(seg_idx); 240 size_t size_bytes = segments.size_in_bytes(seg_idx); 241 242 size_t oop_offset = _buffer_used; 243 _buffer_used = oop_offset + size_bytes; 244 ensure_buffer_space(_buffer_used); 245 246 assert((oop_offset % MIN_GC_REGION_ALIGNMENT) == 0, 247 "Roots segment " SIZE_FORMAT " start is not aligned: " SIZE_FORMAT, 248 segments.count(), oop_offset); 249 250 objArrayOop seg_oop = allocate_root_segment(oop_offset, size_elems); 251 for (int i = 0; i < size_elems; i++) { 252 root_segment_at_put(seg_oop, i, roots->at(root_index++)); 253 } 254 255 log_info(cds, heap)("archived obj root segment [%d] = " SIZE_FORMAT " bytes, obj = " PTR_FORMAT, 256 size_elems, size_bytes, p2i(seg_oop)); 257 } 258 259 assert(root_index == roots->length(), "Post-condition: All roots are handled"); 260 261 _heap_root_segments = segments; 262 } 263 264 // The goal is to sort the objects in increasing order of: 265 // - objects that have only oop pointers 266 // - objects that have both native and oop pointers 267 // - objects that have only native pointers 268 // - objects that have no pointers 269 static int oop_sorting_rank(oop o) { 270 bool has_oop_ptr, has_native_ptr; 271 HeapShared::get_pointer_info(o, has_oop_ptr, has_native_ptr); 272 273 if (has_oop_ptr) { 274 if (!has_native_ptr) { 275 return 0; 276 } else { 277 return 1; 278 } 279 } else { 280 if (has_native_ptr) { 281 return 2; 282 } else { 283 return 3; 284 } 285 } 286 } 287 288 int ArchiveHeapWriter::compare_objs_by_oop_fields(HeapObjOrder* a, HeapObjOrder* b) { 289 int rank_a = a->_rank; 290 int rank_b = b->_rank; 291 292 if (rank_a != rank_b) { 293 return rank_a - rank_b; 294 } else { 295 // If they are the same rank, sort them by their position in the _source_objs array 296 return a->_index - b->_index; 297 } 298 } 299 300 void ArchiveHeapWriter::sort_source_objs() { 301 log_info(cds)("sorting heap objects"); 302 int len = _source_objs->length(); 303 _source_objs_order = new GrowableArrayCHeap<HeapObjOrder, mtClassShared>(len); 304 305 for (int i = 0; i < len; i++) { 306 oop o = _source_objs->at(i); 307 int rank = oop_sorting_rank(o); 308 HeapObjOrder os = {i, rank}; 309 _source_objs_order->append(os); 310 } 311 log_info(cds)("computed ranks"); 312 _source_objs_order->sort(compare_objs_by_oop_fields); 313 log_info(cds)("sorting heap objects done"); 314 } 315 316 void ArchiveHeapWriter::copy_source_objs_to_buffer(GrowableArrayCHeap<oop, mtClassShared>* roots) { 317 // There could be multiple root segments, which we want to be aligned by region. 318 // Putting them ahead of objects makes sure we waste no space. 319 copy_roots_to_buffer(roots); 320 321 sort_source_objs(); 322 for (int i = 0; i < _source_objs_order->length(); i++) { 323 int src_obj_index = _source_objs_order->at(i)._index; 324 oop src_obj = _source_objs->at(src_obj_index); 325 HeapShared::CachedOopInfo* info = HeapShared::archived_object_cache()->get(src_obj); 326 assert(info != nullptr, "must be"); 327 size_t buffer_offset = copy_one_source_obj_to_buffer(src_obj); 328 info->set_buffer_offset(buffer_offset); 329 assert(buffer_offset <= 0x7fffffff, "sanity"); 330 HeapShared::add_to_permanent_oop_table(src_obj, (int)buffer_offset); 331 332 _buffer_offset_to_source_obj_table->put_when_absent(buffer_offset, src_obj); 333 _buffer_offset_to_source_obj_table->maybe_grow(); 334 } 335 336 log_info(cds)("Size of heap region = " SIZE_FORMAT " bytes, %d objects, %d roots, %d native ptrs", 337 _buffer_used, _source_objs->length() + 1, roots->length(), _num_native_ptrs); 338 log_info(cds)(" strings = " SIZE_FORMAT_W(8) " (" SIZE_FORMAT " bytes)", _num_strings, _string_bytes); 339 log_info(cds)(" packages = " SIZE_FORMAT_W(8), _num_packages); 340 log_info(cds)(" protection domains = " SIZE_FORMAT_W(8),_num_protection_domains); 341 } 342 343 size_t ArchiveHeapWriter::filler_array_byte_size(int length) { 344 size_t byte_size = objArrayOopDesc::object_size(length) * HeapWordSize; 345 return byte_size; 346 } 347 348 int ArchiveHeapWriter::filler_array_length(size_t fill_bytes) { 349 assert(is_object_aligned(fill_bytes), "must be"); 350 size_t elemSize = (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop)); 351 352 int initial_length = to_array_length(fill_bytes / elemSize); 353 for (int length = initial_length; length >= 0; length --) { 354 size_t array_byte_size = filler_array_byte_size(length); 355 if (array_byte_size == fill_bytes) { 356 return length; 357 } 358 } 359 360 ShouldNotReachHere(); 361 return -1; 362 } 363 364 HeapWord* ArchiveHeapWriter::init_filler_array_at_buffer_top(int array_length, size_t fill_bytes) { 365 assert(UseCompressedClassPointers, "Archived heap only supported for compressed klasses"); 366 Klass* oak = Universe::objectArrayKlass(); // already relocated to point to archived klass 367 HeapWord* mem = offset_to_buffered_address<HeapWord*>(_buffer_used); 368 memset(mem, 0, fill_bytes); 369 narrowKlass nk = ArchiveBuilder::current()->get_requested_narrow_klass(oak); 370 if (UseCompactObjectHeaders) { 371 oopDesc::release_set_mark(mem, markWord::prototype().set_narrow_klass(nk)); 372 } else { 373 oopDesc::set_mark(mem, markWord::prototype()); 374 cast_to_oop(mem)->set_narrow_klass(nk); 375 } 376 arrayOopDesc::set_length(mem, array_length); 377 return mem; 378 } 379 380 void ArchiveHeapWriter::maybe_fill_gc_region_gap(size_t required_byte_size) { 381 // We fill only with arrays (so we don't need to use a single HeapWord filler if the 382 // leftover space is smaller than a zero-sized array object). Therefore, we need to 383 // make sure there's enough space of min_filler_byte_size in the current region after 384 // required_byte_size has been allocated. If not, fill the remainder of the current 385 // region. 386 size_t min_filler_byte_size = filler_array_byte_size(0); 387 size_t new_used = _buffer_used + required_byte_size + min_filler_byte_size; 388 389 const size_t cur_min_region_bottom = align_down(_buffer_used, MIN_GC_REGION_ALIGNMENT); 390 const size_t next_min_region_bottom = align_down(new_used, MIN_GC_REGION_ALIGNMENT); 391 392 if (cur_min_region_bottom != next_min_region_bottom) { 393 // Make sure that no objects span across MIN_GC_REGION_ALIGNMENT. This way 394 // we can map the region in any region-based collector. 395 assert(next_min_region_bottom > cur_min_region_bottom, "must be"); 396 assert(next_min_region_bottom - cur_min_region_bottom == MIN_GC_REGION_ALIGNMENT, 397 "no buffered object can be larger than %d bytes", MIN_GC_REGION_ALIGNMENT); 398 399 const size_t filler_end = next_min_region_bottom; 400 const size_t fill_bytes = filler_end - _buffer_used; 401 assert(fill_bytes > 0, "must be"); 402 ensure_buffer_space(filler_end); 403 404 int array_length = filler_array_length(fill_bytes); 405 log_info(cds, heap)("Inserting filler obj array of %d elements (" SIZE_FORMAT " bytes total) @ buffer offset " SIZE_FORMAT, 406 array_length, fill_bytes, _buffer_used); 407 HeapWord* filler = init_filler_array_at_buffer_top(array_length, fill_bytes); 408 _buffer_used = filler_end; 409 _fillers->put(buffered_address_to_offset((address)filler), fill_bytes); 410 } 411 } 412 413 size_t ArchiveHeapWriter::get_filler_size_at(address buffered_addr) { 414 size_t* p = _fillers->get(buffered_address_to_offset(buffered_addr)); 415 if (p != nullptr) { 416 assert(*p > 0, "filler must be larger than zero bytes"); 417 return *p; 418 } else { 419 return 0; // buffered_addr is not a filler 420 } 421 } 422 423 template <typename T> 424 void update_buffered_object_field(address buffered_obj, int field_offset, T value) { 425 T* field_addr = cast_to_oop(buffered_obj)->field_addr<T>(field_offset); 426 *field_addr = value; 427 } 428 429 void ArchiveHeapWriter::update_stats(oop src_obj) { 430 if (java_lang_String::is_instance(src_obj)) { 431 _num_strings ++; 432 _string_bytes += src_obj->size() * HeapWordSize; 433 _string_bytes += java_lang_String::value(src_obj)->size() * HeapWordSize; 434 } else { 435 Klass* k = src_obj->klass(); 436 Symbol* name = k->name(); 437 if (name->equals("java/lang/NamedPackage") || name->equals("java/lang/Package")) { 438 _num_packages ++; 439 } else if (name->equals("java/security/ProtectionDomain")) { 440 _num_protection_domains ++; 441 } 442 } 443 } 444 445 size_t ArchiveHeapWriter::copy_one_source_obj_to_buffer(oop src_obj) { 446 update_stats(src_obj); 447 448 assert(!is_too_large_to_archive(src_obj), "already checked"); 449 size_t byte_size = src_obj->size() * HeapWordSize; 450 assert(byte_size > 0, "no zero-size objects"); 451 452 // For region-based collectors such as G1, the archive heap may be mapped into 453 // multiple regions. We need to make sure that we don't have an object that can possible 454 // span across two regions. 455 maybe_fill_gc_region_gap(byte_size); 456 457 size_t new_used = _buffer_used + byte_size; 458 assert(new_used > _buffer_used, "no wrap around"); 459 460 size_t cur_min_region_bottom = align_down(_buffer_used, MIN_GC_REGION_ALIGNMENT); 461 size_t next_min_region_bottom = align_down(new_used, MIN_GC_REGION_ALIGNMENT); 462 assert(cur_min_region_bottom == next_min_region_bottom, "no object should cross minimal GC region boundaries"); 463 464 ensure_buffer_space(new_used); 465 466 address from = cast_from_oop<address>(src_obj); 467 address to = offset_to_buffered_address<address>(_buffer_used); 468 assert(is_object_aligned(_buffer_used), "sanity"); 469 assert(is_object_aligned(byte_size), "sanity"); 470 memcpy(to, from, byte_size); 471 472 // These native pointers will be restored explicitly at run time. 473 if (java_lang_Module::is_instance(src_obj)) { 474 update_buffered_object_field<ModuleEntry*>(to, java_lang_Module::module_entry_offset(), nullptr); 475 } else if (java_lang_ClassLoader::is_instance(src_obj)) { 476 #ifdef ASSERT 477 // We only archive these loaders 478 if (src_obj != SystemDictionary::java_platform_loader() && 479 src_obj != SystemDictionary::java_system_loader()) { 480 assert(src_obj->klass()->name()->equals("jdk/internal/loader/ClassLoaders$BootClassLoader"), "must be"); 481 } 482 #endif 483 update_buffered_object_field<ClassLoaderData*>(to, java_lang_ClassLoader::loader_data_offset(), nullptr); 484 } 485 486 size_t buffered_obj_offset = _buffer_used; 487 _buffer_used = new_used; 488 489 return buffered_obj_offset; 490 } 491 492 void ArchiveHeapWriter::set_requested_address(ArchiveHeapInfo* info) { 493 assert(!info->is_used(), "only set once"); 494 495 size_t heap_region_byte_size = _buffer_used; 496 assert(heap_region_byte_size > 0, "must archived at least one object!"); 497 498 if (UseCompressedOops) { 499 if (UseG1GC) { 500 address heap_end = (address)G1CollectedHeap::heap()->reserved().end(); 501 log_info(cds, heap)("Heap end = %p", heap_end); 502 _requested_bottom = align_down(heap_end - heap_region_byte_size, G1HeapRegion::GrainBytes); 503 _requested_bottom = align_down(_requested_bottom, MIN_GC_REGION_ALIGNMENT); 504 assert(is_aligned(_requested_bottom, G1HeapRegion::GrainBytes), "sanity"); 505 } else { 506 _requested_bottom = align_up(CompressedOops::begin(), MIN_GC_REGION_ALIGNMENT); 507 } 508 } else { 509 // We always write the objects as if the heap started at this address. This 510 // makes the contents of the archive heap deterministic. 511 // 512 // Note that at runtime, the heap address is selected by the OS, so the archive 513 // heap will not be mapped at 0x10000000, and the contents need to be patched. 514 _requested_bottom = align_up((address)NOCOOPS_REQUESTED_BASE, MIN_GC_REGION_ALIGNMENT); 515 } 516 517 assert(is_aligned(_requested_bottom, MIN_GC_REGION_ALIGNMENT), "sanity"); 518 519 _requested_top = _requested_bottom + _buffer_used; 520 521 info->set_buffer_region(MemRegion(offset_to_buffered_address<HeapWord*>(0), 522 offset_to_buffered_address<HeapWord*>(_buffer_used))); 523 info->set_heap_root_segments(_heap_root_segments); 524 } 525 526 // Oop relocation 527 528 template <typename T> T* ArchiveHeapWriter::requested_addr_to_buffered_addr(T* p) { 529 assert(is_in_requested_range(cast_to_oop(p)), "must be"); 530 531 address addr = address(p); 532 assert(addr >= _requested_bottom, "must be"); 533 size_t offset = addr - _requested_bottom; 534 return offset_to_buffered_address<T*>(offset); 535 } 536 537 template <typename T> oop ArchiveHeapWriter::load_source_oop_from_buffer(T* buffered_addr) { 538 oop o = load_oop_from_buffer(buffered_addr); 539 assert(!in_buffer(cast_from_oop<address>(o)), "must point to source oop"); 540 return o; 541 } 542 543 template <typename T> void ArchiveHeapWriter::store_requested_oop_in_buffer(T* buffered_addr, 544 oop request_oop) { 545 assert(is_in_requested_range(request_oop), "must be"); 546 store_oop_in_buffer(buffered_addr, request_oop); 547 } 548 549 inline void ArchiveHeapWriter::store_oop_in_buffer(oop* buffered_addr, oop requested_obj) { 550 *buffered_addr = requested_obj; 551 } 552 553 inline void ArchiveHeapWriter::store_oop_in_buffer(narrowOop* buffered_addr, oop requested_obj) { 554 narrowOop val = CompressedOops::encode_not_null(requested_obj); 555 *buffered_addr = val; 556 } 557 558 oop ArchiveHeapWriter::load_oop_from_buffer(oop* buffered_addr) { 559 return *buffered_addr; 560 } 561 562 oop ArchiveHeapWriter::load_oop_from_buffer(narrowOop* buffered_addr) { 563 return CompressedOops::decode(*buffered_addr); 564 } 565 566 template <typename T> void ArchiveHeapWriter::relocate_field_in_buffer(T* field_addr_in_buffer, CHeapBitMap* oopmap) { 567 oop source_referent = load_source_oop_from_buffer<T>(field_addr_in_buffer); 568 if (source_referent != nullptr) { 569 if (java_lang_Class::is_instance(source_referent)) { 570 // When the source object points to a "real" mirror, the buffered object should point 571 // to the "scratch" mirror, which has all unarchivable fields scrubbed (to be reinstated 572 // at run time). 573 source_referent = HeapShared::scratch_java_mirror(source_referent); 574 assert(source_referent != nullptr, "must be"); 575 } 576 oop request_referent = source_obj_to_requested_obj(source_referent); 577 store_requested_oop_in_buffer<T>(field_addr_in_buffer, request_referent); 578 mark_oop_pointer<T>(field_addr_in_buffer, oopmap); 579 } 580 } 581 582 template <typename T> void ArchiveHeapWriter::mark_oop_pointer(T* buffered_addr, CHeapBitMap* oopmap) { 583 T* request_p = (T*)(buffered_addr_to_requested_addr((address)buffered_addr)); 584 address requested_region_bottom; 585 586 assert(request_p >= (T*)_requested_bottom, "sanity"); 587 assert(request_p < (T*)_requested_top, "sanity"); 588 requested_region_bottom = _requested_bottom; 589 590 // Mark the pointer in the oopmap 591 T* region_bottom = (T*)requested_region_bottom; 592 assert(request_p >= region_bottom, "must be"); 593 BitMap::idx_t idx = request_p - region_bottom; 594 assert(idx < oopmap->size(), "overflow"); 595 oopmap->set_bit(idx); 596 } 597 598 void ArchiveHeapWriter::update_header_for_requested_obj(oop requested_obj, oop src_obj, Klass* src_klass) { 599 assert(UseCompressedClassPointers, "Archived heap only supported for compressed klasses"); 600 narrowKlass nk = ArchiveBuilder::current()->get_requested_narrow_klass(src_klass); 601 address buffered_addr = requested_addr_to_buffered_addr(cast_from_oop<address>(requested_obj)); 602 603 oop fake_oop = cast_to_oop(buffered_addr); 604 if (UseCompactObjectHeaders) { 605 fake_oop->set_mark(markWord::prototype().set_narrow_klass(nk)); 606 } else { 607 fake_oop->set_narrow_klass(nk); 608 } 609 610 if (src_obj == nullptr) { 611 return; 612 } 613 // We need to retain the identity_hash, because it may have been used by some hashtables 614 // in the shared heap. 615 if (!src_obj->fast_no_hash_check()) { 616 intptr_t src_hash = src_obj->identity_hash(); 617 if (UseCompactObjectHeaders) { 618 fake_oop->set_mark(markWord::prototype().set_narrow_klass(nk).copy_set_hash(src_hash)); 619 } else { 620 fake_oop->set_mark(markWord::prototype().copy_set_hash(src_hash)); 621 } 622 assert(fake_oop->mark().is_unlocked(), "sanity"); 623 624 DEBUG_ONLY(intptr_t archived_hash = fake_oop->identity_hash()); 625 assert(src_hash == archived_hash, "Different hash codes: original " INTPTR_FORMAT ", archived " INTPTR_FORMAT, src_hash, archived_hash); 626 } 627 // Strip age bits. 628 fake_oop->set_mark(fake_oop->mark().set_age(0)); 629 } 630 631 class ArchiveHeapWriter::EmbeddedOopRelocator: public BasicOopIterateClosure { 632 oop _src_obj; 633 address _buffered_obj; 634 CHeapBitMap* _oopmap; 635 636 public: 637 EmbeddedOopRelocator(oop src_obj, address buffered_obj, CHeapBitMap* oopmap) : 638 _src_obj(src_obj), _buffered_obj(buffered_obj), _oopmap(oopmap) {} 639 640 void do_oop(narrowOop *p) { EmbeddedOopRelocator::do_oop_work(p); } 641 void do_oop( oop *p) { EmbeddedOopRelocator::do_oop_work(p); } 642 643 private: 644 template <class T> void do_oop_work(T *p) { 645 size_t field_offset = pointer_delta(p, _src_obj, sizeof(char)); 646 ArchiveHeapWriter::relocate_field_in_buffer<T>((T*)(_buffered_obj + field_offset), _oopmap); 647 } 648 }; 649 650 static void log_bitmap_usage(const char* which, BitMap* bitmap, size_t total_bits) { 651 // The whole heap is covered by total_bits, but there are only non-zero bits within [start ... end). 652 size_t start = bitmap->find_first_set_bit(0); 653 size_t end = bitmap->size(); 654 log_info(cds)("%s = " SIZE_FORMAT_W(7) " ... " SIZE_FORMAT_W(7) " (%3zu%% ... %3zu%% = %3zu%%)", which, 655 start, end, 656 start * 100 / total_bits, 657 end * 100 / total_bits, 658 (end - start) * 100 / total_bits); 659 } 660 661 // Update all oop fields embedded in the buffered objects 662 void ArchiveHeapWriter::relocate_embedded_oops(GrowableArrayCHeap<oop, mtClassShared>* roots, 663 ArchiveHeapInfo* heap_info) { 664 size_t oopmap_unit = (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop)); 665 size_t heap_region_byte_size = _buffer_used; 666 heap_info->oopmap()->resize(heap_region_byte_size / oopmap_unit); 667 668 for (int i = 0; i < _source_objs_order->length(); i++) { 669 int src_obj_index = _source_objs_order->at(i)._index; 670 oop src_obj = _source_objs->at(src_obj_index); 671 HeapShared::CachedOopInfo* info = HeapShared::archived_object_cache()->get(src_obj); 672 assert(info != nullptr, "must be"); 673 oop requested_obj = requested_obj_from_buffer_offset(info->buffer_offset()); 674 update_header_for_requested_obj(requested_obj, src_obj, src_obj->klass()); 675 address buffered_obj = offset_to_buffered_address<address>(info->buffer_offset()); 676 EmbeddedOopRelocator relocator(src_obj, buffered_obj, heap_info->oopmap()); 677 src_obj->oop_iterate(&relocator); 678 }; 679 680 // Relocate HeapShared::roots(), which is created in copy_roots_to_buffer() and 681 // doesn't have a corresponding src_obj, so we can't use EmbeddedOopRelocator on it. 682 for (size_t seg_idx = 0; seg_idx < _heap_root_segments.count(); seg_idx++) { 683 size_t seg_offset = _heap_root_segments.segment_offset(seg_idx); 684 685 objArrayOop requested_obj = (objArrayOop)requested_obj_from_buffer_offset(seg_offset); 686 update_header_for_requested_obj(requested_obj, nullptr, Universe::objectArrayKlass()); 687 address buffered_obj = offset_to_buffered_address<address>(seg_offset); 688 int length = _heap_root_segments.size_in_elems(seg_idx); 689 690 if (UseCompressedOops) { 691 for (int i = 0; i < length; i++) { 692 narrowOop* addr = (narrowOop*)(buffered_obj + objArrayOopDesc::obj_at_offset<narrowOop>(i)); 693 relocate_field_in_buffer<narrowOop>(addr, heap_info->oopmap()); 694 } 695 } else { 696 for (int i = 0; i < length; i++) { 697 oop* addr = (oop*)(buffered_obj + objArrayOopDesc::obj_at_offset<oop>(i)); 698 relocate_field_in_buffer<oop>(addr, heap_info->oopmap()); 699 } 700 } 701 } 702 703 compute_ptrmap(heap_info); 704 705 size_t total_bytes = (size_t)_buffer->length(); 706 log_bitmap_usage("oopmap", heap_info->oopmap(), total_bytes / (UseCompressedOops ? sizeof(narrowOop) : sizeof(oop))); 707 log_bitmap_usage("ptrmap", heap_info->ptrmap(), total_bytes / sizeof(address)); 708 } 709 710 void ArchiveHeapWriter::mark_native_pointer(oop src_obj, int field_offset) { 711 Metadata* ptr = src_obj->metadata_field_acquire(field_offset); 712 if (ptr != nullptr) { 713 NativePointerInfo info; 714 info._src_obj = src_obj; 715 info._field_offset = field_offset; 716 _native_pointers->append(info); 717 if (!ArchiveBuilder::current()->has_been_archived((address)ptr)) { 718 // Currently we supporting marking of only Method and Klass, both of which are 719 // subtypes of MetaData. 720 ResourceMark rm; 721 log_error(cds, heap)("Native pointer %p is not archived", ptr); 722 if (((Metadata*)ptr)->is_method()) { 723 log_error(cds, heap)("Method: %s", ((Method*)ptr)->external_name()); 724 } else { 725 assert(((Metadata*)ptr)->is_klass(), "must be"); 726 log_error(cds, heap)("Klass: %s", ((Klass*)ptr)->external_name()); 727 } 728 HeapShared::exit_on_error(); 729 } 730 HeapShared::set_has_native_pointers(src_obj); 731 _num_native_ptrs ++; 732 } 733 } 734 735 // Do we have a jlong/jint field that's actually a pointer to a MetaspaceObj? 736 bool ArchiveHeapWriter::is_marked_as_native_pointer(ArchiveHeapInfo* heap_info, oop src_obj, int field_offset) { 737 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 738 assert(p != nullptr, "must be"); 739 740 // requested_field_addr = the address of this field in the requested space 741 oop requested_obj = requested_obj_from_buffer_offset(p->buffer_offset()); 742 Metadata** requested_field_addr = (Metadata**)(cast_from_oop<address>(requested_obj) + field_offset); 743 assert((Metadata**)_requested_bottom <= requested_field_addr && requested_field_addr < (Metadata**) _requested_top, "range check"); 744 745 BitMap::idx_t idx = requested_field_addr - (Metadata**) _requested_bottom; 746 // Leading zeros have been removed so some addresses may not be in the ptrmap 747 size_t start_pos = FileMapInfo::current_info()->heap_ptrmap_start_pos(); 748 if (idx < start_pos) { 749 return false; 750 } else { 751 idx -= start_pos; 752 } 753 return (idx < heap_info->ptrmap()->size()) && (heap_info->ptrmap()->at(idx) == true); 754 } 755 756 void ArchiveHeapWriter::compute_ptrmap(ArchiveHeapInfo* heap_info) { 757 int num_non_null_ptrs = 0; 758 Metadata** bottom = (Metadata**) _requested_bottom; 759 Metadata** top = (Metadata**) _requested_top; // exclusive 760 heap_info->ptrmap()->resize(top - bottom); 761 762 BitMap::idx_t max_idx = 32; // paranoid - don't make it too small 763 for (int i = 0; i < _native_pointers->length(); i++) { 764 NativePointerInfo info = _native_pointers->at(i); 765 oop src_obj = info._src_obj; 766 int field_offset = info._field_offset; 767 HeapShared::CachedOopInfo* p = HeapShared::archived_object_cache()->get(src_obj); 768 // requested_field_addr = the address of this field in the requested space 769 oop requested_obj = requested_obj_from_buffer_offset(p->buffer_offset()); 770 Metadata** requested_field_addr = (Metadata**)(cast_from_oop<address>(requested_obj) + field_offset); 771 assert(bottom <= requested_field_addr && requested_field_addr < top, "range check"); 772 773 // Mark this field in the bitmap 774 BitMap::idx_t idx = requested_field_addr - bottom; 775 heap_info->ptrmap()->set_bit(idx); 776 num_non_null_ptrs ++; 777 max_idx = MAX2(max_idx, idx); 778 779 // Set the native pointer to the requested address of the metadata (at runtime, the metadata will have 780 // this address if the RO/RW regions are mapped at the default location). 781 782 Metadata** buffered_field_addr = requested_addr_to_buffered_addr(requested_field_addr); 783 Metadata* native_ptr = *buffered_field_addr; 784 guarantee(native_ptr != nullptr, "sanity"); 785 guarantee(ArchiveBuilder::current()->has_been_buffered((address)native_ptr), 786 "Metadata %p should have been archived", native_ptr); 787 788 if (RegeneratedClasses::has_been_regenerated((address)native_ptr)) { 789 native_ptr = (Metadata*)RegeneratedClasses::get_regenerated_object((address)native_ptr); 790 } 791 792 address buffered_native_ptr = ArchiveBuilder::current()->get_buffered_addr((address)native_ptr); 793 address requested_native_ptr = ArchiveBuilder::current()->to_requested(buffered_native_ptr); 794 *buffered_field_addr = (Metadata*)requested_native_ptr; 795 } 796 797 heap_info->ptrmap()->resize(max_idx + 1); 798 log_info(cds, heap)("calculate_ptrmap: marked %d non-null native pointers for heap region (" SIZE_FORMAT " bits)", 799 num_non_null_ptrs, size_t(heap_info->ptrmap()->size())); 800 } 801 802 #endif // INCLUDE_CDS_JAVA_HEAP