1 /* 2 * Copyright (c) 2005, 2024, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2023, Alibaba Group Holding Limited. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #include "precompiled.hpp" 27 #include "classfile/classLoaderData.inline.hpp" 28 #include "classfile/classLoaderDataGraph.hpp" 29 #include "classfile/javaClasses.inline.hpp" 30 #include "classfile/symbolTable.hpp" 31 #include "classfile/vmClasses.hpp" 32 #include "classfile/vmSymbols.hpp" 33 #include "gc/shared/gcLocker.hpp" 34 #include "gc/shared/gcVMOperations.hpp" 35 #include "gc/shared/workerThread.hpp" 36 #include "jfr/jfrEvents.hpp" 37 #include "jvm.h" 38 #include "memory/allocation.inline.hpp" 39 #include "memory/resourceArea.hpp" 40 #include "memory/universe.hpp" 41 #include "oops/fieldStreams.inline.hpp" 42 #include "oops/klass.inline.hpp" 43 #include "oops/objArrayKlass.hpp" 44 #include "oops/objArrayOop.inline.hpp" 45 #include "oops/flatArrayKlass.hpp" 46 #include "oops/flatArrayOop.inline.hpp" 47 #include "oops/oop.inline.hpp" 48 #include "oops/typeArrayOop.inline.hpp" 49 #include "runtime/continuationWrapper.inline.hpp" 50 #include "runtime/fieldDescriptor.inline.hpp" 51 #include "runtime/frame.inline.hpp" 52 #include "runtime/handles.inline.hpp" 53 #include "runtime/javaCalls.hpp" 54 #include "runtime/javaThread.inline.hpp" 55 #include "runtime/jniHandles.hpp" 56 #include "runtime/os.hpp" 57 #include "runtime/threads.hpp" 58 #include "runtime/threadSMR.hpp" 59 #include "runtime/vframe.hpp" 60 #include "runtime/vmOperations.hpp" 61 #include "runtime/vmThread.hpp" 62 #include "runtime/timerTrace.hpp" 63 #include "services/heapDumper.hpp" 64 #include "services/heapDumperCompression.hpp" 65 #include "services/threadService.hpp" 66 #include "utilities/checkedCast.hpp" 67 #include "utilities/macros.hpp" 68 #include "utilities/ostream.hpp" 69 #ifdef LINUX 70 #include "os_linux.hpp" 71 #endif 72 73 /* 74 * HPROF binary format - description copied from: 75 * src/share/demo/jvmti/hprof/hprof_io.c 76 * 77 * 78 * header "JAVA PROFILE 1.0.2" (0-terminated) 79 * 80 * u4 size of identifiers. Identifiers are used to represent 81 * UTF8 strings, objects, stack traces, etc. They usually 82 * have the same size as host pointers. 83 * u4 high word 84 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70 85 * [record]* a sequence of records. 86 * 87 * 88 * Record format: 89 * 90 * u1 a TAG denoting the type of the record 91 * u4 number of *microseconds* since the time stamp in the 92 * header. (wraps around in a little more than an hour) 93 * u4 number of bytes *remaining* in the record. Note that 94 * this number excludes the tag and the length field itself. 95 * [u1]* BODY of the record (a sequence of bytes) 96 * 97 * 98 * The following TAGs are supported: 99 * 100 * TAG BODY notes 101 *---------------------------------------------------------- 102 * HPROF_UTF8 a UTF8-encoded name 103 * 104 * id name ID 105 * [u1]* UTF8 characters (no trailing zero) 106 * 107 * HPROF_LOAD_CLASS a newly loaded class 108 * 109 * u4 class serial number (> 0) 110 * id class object ID 111 * u4 stack trace serial number 112 * id class name ID 113 * 114 * HPROF_UNLOAD_CLASS an unloading class 115 * 116 * u4 class serial_number 117 * 118 * HPROF_FRAME a Java stack frame 119 * 120 * id stack frame ID 121 * id method name ID 122 * id method signature ID 123 * id source file name ID 124 * u4 class serial number 125 * i4 line number. >0: normal 126 * -1: unknown 127 * -2: compiled method 128 * -3: native method 129 * 130 * HPROF_TRACE a Java stack trace 131 * 132 * u4 stack trace serial number 133 * u4 thread serial number 134 * u4 number of frames 135 * [id]* stack frame IDs 136 * 137 * 138 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC 139 * 140 * u2 flags 0x0001: incremental vs. complete 141 * 0x0002: sorted by allocation vs. live 142 * 0x0004: whether to force a GC 143 * u4 cutoff ratio 144 * u4 total live bytes 145 * u4 total live instances 146 * u8 total bytes allocated 147 * u8 total instances allocated 148 * u4 number of sites that follow 149 * [u1 is_array: 0: normal object 150 * 2: object array 151 * 4: boolean array 152 * 5: char array 153 * 6: float array 154 * 7: double array 155 * 8: byte array 156 * 9: short array 157 * 10: int array 158 * 11: long array 159 * u4 class serial number (may be zero during startup) 160 * u4 stack trace serial number 161 * u4 number of bytes alive 162 * u4 number of instances alive 163 * u4 number of bytes allocated 164 * u4]* number of instance allocated 165 * 166 * HPROF_START_THREAD a newly started thread. 167 * 168 * u4 thread serial number (> 0) 169 * id thread object ID 170 * u4 stack trace serial number 171 * id thread name ID 172 * id thread group name ID 173 * id thread group parent name ID 174 * 175 * HPROF_END_THREAD a terminating thread. 176 * 177 * u4 thread serial number 178 * 179 * HPROF_HEAP_SUMMARY heap summary 180 * 181 * u4 total live bytes 182 * u4 total live instances 183 * u8 total bytes allocated 184 * u8 total instances allocated 185 * 186 * HPROF_HEAP_DUMP denote a heap dump 187 * 188 * [heap dump sub-records]* 189 * 190 * There are four kinds of heap dump sub-records: 191 * 192 * u1 sub-record type 193 * 194 * HPROF_GC_ROOT_UNKNOWN unknown root 195 * 196 * id object ID 197 * 198 * HPROF_GC_ROOT_THREAD_OBJ thread object 199 * 200 * id thread object ID (may be 0 for a 201 * thread newly attached through JNI) 202 * u4 thread sequence number 203 * u4 stack trace sequence number 204 * 205 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root 206 * 207 * id object ID 208 * id JNI global ref ID 209 * 210 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref 211 * 212 * id object ID 213 * u4 thread serial number 214 * u4 frame # in stack trace (-1 for empty) 215 * 216 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame 217 * 218 * id object ID 219 * u4 thread serial number 220 * u4 frame # in stack trace (-1 for empty) 221 * 222 * HPROF_GC_ROOT_NATIVE_STACK Native stack 223 * 224 * id object ID 225 * u4 thread serial number 226 * 227 * HPROF_GC_ROOT_STICKY_CLASS System class 228 * 229 * id object ID 230 * 231 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block 232 * 233 * id object ID 234 * u4 thread serial number 235 * 236 * HPROF_GC_ROOT_MONITOR_USED Busy monitor 237 * 238 * id object ID 239 * 240 * HPROF_GC_CLASS_DUMP dump of a class object 241 * 242 * id class object ID 243 * u4 stack trace serial number 244 * id super class object ID 245 * id class loader object ID 246 * id signers object ID 247 * id protection domain object ID 248 * id reserved 249 * id reserved 250 * 251 * u4 instance size (in bytes) 252 * 253 * u2 size of constant pool 254 * [u2, constant pool index, 255 * ty, type 256 * 2: object 257 * 4: boolean 258 * 5: char 259 * 6: float 260 * 7: double 261 * 8: byte 262 * 9: short 263 * 10: int 264 * 11: long 265 * vl]* and value 266 * 267 * u2 number of static fields 268 * [id, static field name, 269 * ty, type, 270 * vl]* and value 271 * 272 * u2 number of inst. fields (not inc. super) 273 * [id, instance field name, 274 * ty]* type 275 * 276 * HPROF_GC_INSTANCE_DUMP dump of a normal object 277 * 278 * id object ID 279 * u4 stack trace serial number 280 * id class object ID 281 * u4 number of bytes that follow 282 * [vl]* instance field values (class, followed 283 * by super, super's super ...) 284 * 285 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array 286 * 287 * id array object ID 288 * u4 stack trace serial number 289 * u4 number of elements 290 * id array class ID 291 * [id]* elements 292 * 293 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array 294 * 295 * id array object ID 296 * u4 stack trace serial number 297 * u4 number of elements 298 * u1 element type 299 * 4: boolean array 300 * 5: char array 301 * 6: float array 302 * 7: double array 303 * 8: byte array 304 * 9: short array 305 * 10: int array 306 * 11: long array 307 * [u1]* elements 308 * 309 * HPROF_CPU_SAMPLES a set of sample traces of running threads 310 * 311 * u4 total number of samples 312 * u4 # of traces 313 * [u4 # of samples 314 * u4]* stack trace serial number 315 * 316 * HPROF_CONTROL_SETTINGS the settings of on/off switches 317 * 318 * u4 0x00000001: alloc traces on/off 319 * 0x00000002: cpu sampling on/off 320 * u2 stack trace depth 321 * 322 * HPROF_FLAT_ARRAYS list of flat arrays 323 * 324 * [flat array sub-records]* 325 * 326 * HPROF_FLAT_ARRAY flat array 327 * 328 * id array object ID (dumped as HPROF_GC_PRIM_ARRAY_DUMP) 329 * id element class ID (dumped by HPROF_GC_CLASS_DUMP) 330 * 331 * HPROF_INLINED_FIELDS decribes inlined fields 332 * 333 * [class with inlined fields sub-records]* 334 * 335 * HPROF_CLASS_WITH_INLINED_FIELDS 336 * 337 * id class ID (dumped as HPROF_GC_CLASS_DUMP) 338 * 339 * u2 number of instance inlined fields (not including super) 340 * [u2, inlined field index, 341 * u2, synthetic field count, 342 * id, original field name, 343 * id]* inlined field class ID (dumped by HPROF_GC_CLASS_DUMP) 344 * 345 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally 346 * be generated as a sequence of heap dump segments. This sequence is 347 * terminated by an end record. The additional tags allowed by format 348 * "JAVA PROFILE 1.0.2" are: 349 * 350 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment 351 * 352 * [heap dump sub-records]* 353 * The same sub-record types allowed by HPROF_HEAP_DUMP 354 * 355 * HPROF_HEAP_DUMP_END denotes the end of a heap dump 356 * 357 */ 358 359 360 // HPROF tags 361 362 enum hprofTag : u1 { 363 // top-level records 364 HPROF_UTF8 = 0x01, 365 HPROF_LOAD_CLASS = 0x02, 366 HPROF_UNLOAD_CLASS = 0x03, 367 HPROF_FRAME = 0x04, 368 HPROF_TRACE = 0x05, 369 HPROF_ALLOC_SITES = 0x06, 370 HPROF_HEAP_SUMMARY = 0x07, 371 HPROF_START_THREAD = 0x0A, 372 HPROF_END_THREAD = 0x0B, 373 HPROF_HEAP_DUMP = 0x0C, 374 HPROF_CPU_SAMPLES = 0x0D, 375 HPROF_CONTROL_SETTINGS = 0x0E, 376 377 // 1.0.2 record types 378 HPROF_HEAP_DUMP_SEGMENT = 0x1C, 379 HPROF_HEAP_DUMP_END = 0x2C, 380 381 // inlined object support 382 HPROF_FLAT_ARRAYS = 0x12, 383 HPROF_INLINED_FIELDS = 0x13, 384 // inlined object subrecords 385 HPROF_FLAT_ARRAY = 0x01, 386 HPROF_CLASS_WITH_INLINED_FIELDS = 0x01, 387 388 // field types 389 HPROF_ARRAY_OBJECT = 0x01, 390 HPROF_NORMAL_OBJECT = 0x02, 391 HPROF_BOOLEAN = 0x04, 392 HPROF_CHAR = 0x05, 393 HPROF_FLOAT = 0x06, 394 HPROF_DOUBLE = 0x07, 395 HPROF_BYTE = 0x08, 396 HPROF_SHORT = 0x09, 397 HPROF_INT = 0x0A, 398 HPROF_LONG = 0x0B, 399 400 // data-dump sub-records 401 HPROF_GC_ROOT_UNKNOWN = 0xFF, 402 HPROF_GC_ROOT_JNI_GLOBAL = 0x01, 403 HPROF_GC_ROOT_JNI_LOCAL = 0x02, 404 HPROF_GC_ROOT_JAVA_FRAME = 0x03, 405 HPROF_GC_ROOT_NATIVE_STACK = 0x04, 406 HPROF_GC_ROOT_STICKY_CLASS = 0x05, 407 HPROF_GC_ROOT_THREAD_BLOCK = 0x06, 408 HPROF_GC_ROOT_MONITOR_USED = 0x07, 409 HPROF_GC_ROOT_THREAD_OBJ = 0x08, 410 HPROF_GC_CLASS_DUMP = 0x20, 411 HPROF_GC_INSTANCE_DUMP = 0x21, 412 HPROF_GC_OBJ_ARRAY_DUMP = 0x22, 413 HPROF_GC_PRIM_ARRAY_DUMP = 0x23 414 }; 415 416 // Default stack trace ID (used for dummy HPROF_TRACE record) 417 enum { 418 STACK_TRACE_ID = 1, 419 INITIAL_CLASS_COUNT = 200 420 }; 421 422 423 class AbstractDumpWriter; 424 425 class InlinedObjects { 426 427 struct ClassInlinedFields { 428 const Klass *klass; 429 uintx base_index; // base index of the inlined field names (1st field has index base_index+1). 430 ClassInlinedFields(const Klass *klass = nullptr, uintx base_index = 0) : klass(klass), base_index(base_index) {} 431 432 // For GrowableArray::find_sorted(). 433 static int compare(const ClassInlinedFields& a, const ClassInlinedFields& b) { 434 return a.klass - b.klass; 435 } 436 // For GrowableArray::sort(). 437 static int compare(ClassInlinedFields* a, ClassInlinedFields* b) { 438 return compare(*a, *b); 439 } 440 }; 441 442 uintx _min_string_id; 443 uintx _max_string_id; 444 445 GrowableArray<ClassInlinedFields> *_inlined_field_map; 446 447 // counters for classes with inlined fields and for the fields 448 int _classes_count; 449 int _inlined_fields_count; 450 451 static InlinedObjects *_instance; 452 453 static void inlined_field_names_callback(InlinedObjects* _this, const Klass *klass, uintx base_index, int count); 454 455 GrowableArray<oop> *_flat_arrays; 456 457 public: 458 InlinedObjects() 459 : _min_string_id(0), _max_string_id(0), 460 _inlined_field_map(nullptr), 461 _classes_count(0), _inlined_fields_count(0), 462 _flat_arrays(nullptr) { 463 } 464 465 static InlinedObjects* get_instance() { 466 return _instance; 467 } 468 469 void init(); 470 void release(); 471 472 void dump_inlined_field_names(AbstractDumpWriter *writer); 473 474 uintx get_base_index_for(Klass* k); 475 uintx get_next_string_id(uintx id); 476 477 void dump_classed_with_inlined_fields(AbstractDumpWriter* writer); 478 479 void add_flat_array(oop array); 480 void dump_flat_arrays(AbstractDumpWriter* writer); 481 482 }; 483 484 InlinedObjects *InlinedObjects::_instance = nullptr; 485 486 487 // Supports I/O operations for a dump 488 // Base class for dump and parallel dump 489 class AbstractDumpWriter : public CHeapObj<mtInternal> { 490 protected: 491 enum { 492 io_buffer_max_size = 1*M, 493 dump_segment_header_size = 9 494 }; 495 496 char* _buffer; // internal buffer 497 size_t _size; 498 size_t _pos; 499 500 bool _in_dump_segment; // Are we currently in a dump segment? 501 bool _is_huge_sub_record; // Are we writing a sub-record larger than the buffer size? 502 DEBUG_ONLY(size_t _sub_record_left;) // The bytes not written for the current sub-record. 503 DEBUG_ONLY(bool _sub_record_ended;) // True if we have called the end_sub_record(). 504 505 char* buffer() const { return _buffer; } 506 size_t buffer_size() const { return _size; } 507 void set_position(size_t pos) { _pos = pos; } 508 509 // Can be called if we have enough room in the buffer. 510 void write_fast(const void* s, size_t len); 511 512 // Returns true if we have enough room in the buffer for 'len' bytes. 513 bool can_write_fast(size_t len); 514 515 void write_address(address a); 516 517 public: 518 AbstractDumpWriter() : 519 _buffer(nullptr), 520 _size(io_buffer_max_size), 521 _pos(0), 522 _in_dump_segment(false) { } 523 524 // Total number of bytes written to the disk 525 virtual julong bytes_written() const = 0; 526 // Return non-null if error occurred 527 virtual char const* error() const = 0; 528 529 size_t position() const { return _pos; } 530 // writer functions 531 virtual void write_raw(const void* s, size_t len); 532 void write_u1(u1 x); 533 void write_u2(u2 x); 534 void write_u4(u4 x); 535 void write_u8(u8 x); 536 void write_objectID(oop o); 537 void write_rootID(oop* p); 538 void write_symbolID(Symbol* o); 539 void write_classID(Klass* k); 540 void write_id(u4 x); 541 542 // Start a new sub-record. Starts a new heap dump segment if needed. 543 void start_sub_record(u1 tag, u4 len); 544 // Ends the current sub-record. 545 void end_sub_record(); 546 // Finishes the current dump segment if not already finished. 547 void finish_dump_segment(); 548 // Flush internal buffer to persistent storage 549 virtual void flush() = 0; 550 }; 551 552 void AbstractDumpWriter::write_fast(const void* s, size_t len) { 553 assert(!_in_dump_segment || (_sub_record_left >= len), "sub-record too large"); 554 assert(buffer_size() - position() >= len, "Must fit"); 555 debug_only(_sub_record_left -= len); 556 memcpy(buffer() + position(), s, len); 557 set_position(position() + len); 558 } 559 560 bool AbstractDumpWriter::can_write_fast(size_t len) { 561 return buffer_size() - position() >= len; 562 } 563 564 // write raw bytes 565 void AbstractDumpWriter::write_raw(const void* s, size_t len) { 566 assert(!_in_dump_segment || (_sub_record_left >= len), "sub-record too large"); 567 debug_only(_sub_record_left -= len); 568 569 // flush buffer to make room. 570 while (len > buffer_size() - position()) { 571 assert(!_in_dump_segment || _is_huge_sub_record, 572 "Cannot overflow in non-huge sub-record."); 573 size_t to_write = buffer_size() - position(); 574 memcpy(buffer() + position(), s, to_write); 575 s = (void*) ((char*) s + to_write); 576 len -= to_write; 577 set_position(position() + to_write); 578 flush(); 579 } 580 581 memcpy(buffer() + position(), s, len); 582 set_position(position() + len); 583 } 584 585 // Makes sure we inline the fast write into the write_u* functions. This is a big speedup. 586 #define WRITE_KNOWN_TYPE(p, len) do { if (can_write_fast((len))) write_fast((p), (len)); \ 587 else write_raw((p), (len)); } while (0) 588 589 void AbstractDumpWriter::write_u1(u1 x) { 590 WRITE_KNOWN_TYPE(&x, 1); 591 } 592 593 void AbstractDumpWriter::write_u2(u2 x) { 594 u2 v; 595 Bytes::put_Java_u2((address)&v, x); 596 WRITE_KNOWN_TYPE(&v, 2); 597 } 598 599 void AbstractDumpWriter::write_u4(u4 x) { 600 u4 v; 601 Bytes::put_Java_u4((address)&v, x); 602 WRITE_KNOWN_TYPE(&v, 4); 603 } 604 605 void AbstractDumpWriter::write_u8(u8 x) { 606 u8 v; 607 Bytes::put_Java_u8((address)&v, x); 608 WRITE_KNOWN_TYPE(&v, 8); 609 } 610 611 void AbstractDumpWriter::write_address(address a) { 612 #ifdef _LP64 613 write_u8((u8)a); 614 #else 615 write_u4((u4)a); 616 #endif 617 } 618 619 void AbstractDumpWriter::write_objectID(oop o) { 620 write_address(cast_from_oop<address>(o)); 621 } 622 623 void AbstractDumpWriter::write_rootID(oop* p) { 624 write_address((address)p); 625 } 626 627 void AbstractDumpWriter::write_symbolID(Symbol* s) { 628 write_address((address)((uintptr_t)s)); 629 } 630 631 void AbstractDumpWriter::write_id(u4 x) { 632 #ifdef _LP64 633 write_u8((u8) x); 634 #else 635 write_u4(x); 636 #endif 637 } 638 639 // We use java mirror as the class ID 640 void AbstractDumpWriter::write_classID(Klass* k) { 641 write_objectID(k->java_mirror()); 642 } 643 644 void AbstractDumpWriter::finish_dump_segment() { 645 if (_in_dump_segment) { 646 assert(_sub_record_left == 0, "Last sub-record not written completely"); 647 assert(_sub_record_ended, "sub-record must have ended"); 648 649 // Fix up the dump segment length if we haven't written a huge sub-record last 650 // (in which case the segment length was already set to the correct value initially). 651 if (!_is_huge_sub_record) { 652 assert(position() > dump_segment_header_size, "Dump segment should have some content"); 653 Bytes::put_Java_u4((address) (buffer() + 5), 654 (u4) (position() - dump_segment_header_size)); 655 } else { 656 // Finish process huge sub record 657 // Set _is_huge_sub_record to false so the parallel dump writer can flush data to file. 658 _is_huge_sub_record = false; 659 } 660 661 _in_dump_segment = false; 662 flush(); 663 } 664 } 665 666 void AbstractDumpWriter::start_sub_record(u1 tag, u4 len) { 667 if (!_in_dump_segment) { 668 if (position() > 0) { 669 flush(); 670 } 671 672 assert(position() == 0 && buffer_size() > dump_segment_header_size, "Must be at the start"); 673 674 write_u1(HPROF_HEAP_DUMP_SEGMENT); 675 write_u4(0); // timestamp 676 // Will be fixed up later if we add more sub-records. If this is a huge sub-record, 677 // this is already the correct length, since we don't add more sub-records. 678 write_u4(len); 679 assert(Bytes::get_Java_u4((address)(buffer() + 5)) == len, "Inconsistent size!"); 680 _in_dump_segment = true; 681 _is_huge_sub_record = len > buffer_size() - dump_segment_header_size; 682 } else if (_is_huge_sub_record || (len > buffer_size() - position())) { 683 // This object will not fit in completely or the last sub-record was huge. 684 // Finish the current segment and try again. 685 finish_dump_segment(); 686 start_sub_record(tag, len); 687 688 return; 689 } 690 691 debug_only(_sub_record_left = len); 692 debug_only(_sub_record_ended = false); 693 694 write_u1(tag); 695 } 696 697 void AbstractDumpWriter::end_sub_record() { 698 assert(_in_dump_segment, "must be in dump segment"); 699 assert(_sub_record_left == 0, "sub-record not written completely"); 700 assert(!_sub_record_ended, "Must not have ended yet"); 701 debug_only(_sub_record_ended = true); 702 } 703 704 // Supports I/O operations for a dump 705 706 class DumpWriter : public AbstractDumpWriter { 707 private: 708 FileWriter* _writer; 709 AbstractCompressor* _compressor; 710 size_t _bytes_written; 711 char* _error; 712 // Compression support 713 char* _out_buffer; 714 size_t _out_size; 715 size_t _out_pos; 716 char* _tmp_buffer; 717 size_t _tmp_size; 718 719 private: 720 void do_compress(); 721 722 public: 723 DumpWriter(const char* path, bool overwrite, AbstractCompressor* compressor); 724 ~DumpWriter(); 725 julong bytes_written() const override { return (julong) _bytes_written; } 726 char const* error() const override { return _error; } 727 void set_error(const char* error) { _error = (char*)error; } 728 bool has_error() const { return _error != nullptr; } 729 const char* get_file_path() const { return _writer->get_file_path(); } 730 AbstractCompressor* compressor() { return _compressor; } 731 bool is_overwrite() const { return _writer->is_overwrite(); } 732 733 void flush() override; 734 735 private: 736 // internals for DumpMerger 737 friend class DumpMerger; 738 void set_bytes_written(julong bytes_written) { _bytes_written = bytes_written; } 739 int get_fd() const { return _writer->get_fd(); } 740 void set_compressor(AbstractCompressor* p) { _compressor = p; } 741 }; 742 743 DumpWriter::DumpWriter(const char* path, bool overwrite, AbstractCompressor* compressor) : 744 AbstractDumpWriter(), 745 _writer(new (std::nothrow) FileWriter(path, overwrite)), 746 _compressor(compressor), 747 _bytes_written(0), 748 _error(nullptr), 749 _out_buffer(nullptr), 750 _out_size(0), 751 _out_pos(0), 752 _tmp_buffer(nullptr), 753 _tmp_size(0) { 754 _error = (char*)_writer->open_writer(); 755 if (_error == nullptr) { 756 _buffer = (char*)os::malloc(io_buffer_max_size, mtInternal); 757 if (compressor != nullptr) { 758 _error = (char*)_compressor->init(io_buffer_max_size, &_out_size, &_tmp_size); 759 if (_error == nullptr) { 760 if (_out_size > 0) { 761 _out_buffer = (char*)os::malloc(_out_size, mtInternal); 762 } 763 if (_tmp_size > 0) { 764 _tmp_buffer = (char*)os::malloc(_tmp_size, mtInternal); 765 } 766 } 767 } 768 } 769 // initialize internal buffer 770 _pos = 0; 771 _size = io_buffer_max_size; 772 } 773 774 DumpWriter::~DumpWriter(){ 775 if (_buffer != nullptr) { 776 os::free(_buffer); 777 } 778 if (_out_buffer != nullptr) { 779 os::free(_out_buffer); 780 } 781 if (_tmp_buffer != nullptr) { 782 os::free(_tmp_buffer); 783 } 784 if (_writer != nullptr) { 785 delete _writer; 786 } 787 _bytes_written = -1; 788 } 789 790 // flush any buffered bytes to the file 791 void DumpWriter::flush() { 792 if (_pos <= 0) { 793 return; 794 } 795 if (has_error()) { 796 _pos = 0; 797 return; 798 } 799 char* result = nullptr; 800 if (_compressor == nullptr) { 801 result = (char*)_writer->write_buf(_buffer, _pos); 802 _bytes_written += _pos; 803 } else { 804 do_compress(); 805 if (!has_error()) { 806 result = (char*)_writer->write_buf(_out_buffer, _out_pos); 807 _bytes_written += _out_pos; 808 } 809 } 810 _pos = 0; // reset pos to make internal buffer available 811 812 if (result != nullptr) { 813 set_error(result); 814 } 815 } 816 817 void DumpWriter::do_compress() { 818 const char* msg = _compressor->compress(_buffer, _pos, _out_buffer, _out_size, 819 _tmp_buffer, _tmp_size, &_out_pos); 820 821 if (msg != nullptr) { 822 set_error(msg); 823 } 824 } 825 826 class DumperClassCacheTable; 827 class DumperClassCacheTableEntry; 828 829 // Support class with a collection of functions used when dumping the heap 830 class DumperSupport : AllStatic { 831 public: 832 833 // write a header of the given type 834 static void write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len); 835 836 // returns hprof tag for the given type signature 837 static hprofTag sig2tag(Symbol* sig); 838 // returns hprof tag for the given basic type 839 static hprofTag type2tag(BasicType type); 840 // Returns the size of the data to write. 841 static u4 sig2size(Symbol* sig); 842 843 // calculates the total size of the all fields of the given class. 844 static u4 instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry = nullptr); 845 846 // dump a jfloat 847 static void dump_float(AbstractDumpWriter* writer, jfloat f); 848 // dump a jdouble 849 static void dump_double(AbstractDumpWriter* writer, jdouble d); 850 // dumps the raw value of the given field 851 static void dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset); 852 // returns the size of the static fields; also counts the static fields 853 static u4 get_static_fields_size(InstanceKlass* ik, u2& field_count); 854 // dumps static fields of the given class 855 static void dump_static_fields(AbstractDumpWriter* writer, Klass* k); 856 // dump the raw values of the instance fields of the given identity or inlined object; 857 // for identity objects offset is 0 and 'klass' is o->klass(), 858 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class 859 static void dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry); 860 // dump the raw values of the instance fields of the given inlined object; 861 // dump_instance_fields wrapper for inlined objects 862 static void dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry); 863 864 // get the count of the instance fields for a given class 865 static u2 get_instance_fields_count(InstanceKlass* ik); 866 // dumps the definition of the instance fields for a given class 867 static void dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* k, uintx *inlined_fields_index = nullptr); 868 // creates HPROF_GC_INSTANCE_DUMP record for the given object 869 static void dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache); 870 // creates HPROF_GC_CLASS_DUMP record for the given instance class 871 static void dump_instance_class(AbstractDumpWriter* writer, Klass* k); 872 // creates HPROF_GC_CLASS_DUMP record for a given array class 873 static void dump_array_class(AbstractDumpWriter* writer, Klass* k); 874 875 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 876 static void dump_object_array(AbstractDumpWriter* writer, objArrayOop array); 877 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array 878 static void dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache); 879 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 880 static void dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array); 881 // create HPROF_FRAME record for the given method and bci 882 static void dump_stack_frame(AbstractDumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci); 883 884 // check if we need to truncate an array 885 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size); 886 // extended version to dump flat arrays as primitive arrays; 887 // type_size specifies size of the inlined objects. 888 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size); 889 890 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record 891 static void end_of_dump(AbstractDumpWriter* writer); 892 893 static oop mask_dormant_archived_object(oop o, oop ref_obj) { 894 if (o != nullptr && o->klass()->java_mirror_no_keepalive() == nullptr) { 895 // Ignore this object since the corresponding java mirror is not loaded. 896 // Might be a dormant archive object. 897 report_dormant_archived_object(o, ref_obj); 898 return nullptr; 899 } else { 900 return o; 901 } 902 } 903 904 // helper methods for inlined fields. 905 static bool is_inlined_field(const fieldDescriptor& fld) { 906 return fld.is_flat(); 907 } 908 static InlineKlass* get_inlined_field_klass(const fieldDescriptor& fld) { 909 assert(is_inlined_field(fld), "must be inlined field"); 910 InstanceKlass* holder_klass = fld.field_holder(); 911 return InlineKlass::cast(holder_klass->get_inline_type_field_klass(fld.index())); 912 } 913 914 static void report_dormant_archived_object(oop o, oop ref_obj) { 915 if (log_is_enabled(Trace, cds, heap)) { 916 ResourceMark rm; 917 if (ref_obj != nullptr) { 918 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)", 919 p2i(o), o->klass()->external_name(), 920 p2i(ref_obj), ref_obj->klass()->external_name()); 921 } else { 922 log_trace(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s)", 923 p2i(o), o->klass()->external_name()); 924 } 925 } 926 } 927 }; 928 929 // Hash table of klasses to the klass metadata. This should greatly improve the 930 // hash dumping performance. This hash table is supposed to be used by a single 931 // thread only. 932 // 933 class DumperClassCacheTableEntry : public CHeapObj<mtServiceability> { 934 friend class DumperClassCacheTable; 935 private: 936 GrowableArray<char> _sigs_start; 937 GrowableArray<int> _offsets; 938 GrowableArray<InlineKlass*> _inline_klasses; 939 u4 _instance_size; 940 int _entries; 941 942 public: 943 DumperClassCacheTableEntry() : _instance_size(0), _entries(0) {}; 944 945 int field_count() { return _entries; } 946 char sig_start(int field_idx) { return _sigs_start.at(field_idx); } 947 void push_sig_start_inlined() { _sigs_start.push('Q'); } 948 bool is_inlined(int field_idx){ return _sigs_start.at(field_idx) == 'Q'; } 949 InlineKlass* inline_klass(int field_idx) { assert(is_inlined(field_idx), "Not inlined"); return _inline_klasses.at(field_idx); } 950 int offset(int field_idx) { return _offsets.at(field_idx); } 951 u4 instance_size() { return _instance_size; } 952 }; 953 954 class DumperClassCacheTable { 955 private: 956 // ResourceHashtable SIZE is specified at compile time so we 957 // use 1031 which is the first prime after 1024. 958 static constexpr size_t TABLE_SIZE = 1031; 959 960 // Maintain the cache for N classes. This limits memory footprint 961 // impact, regardless of how many classes we have in the dump. 962 // This also improves look up performance by keeping the statically 963 // sized table from overloading. 964 static constexpr int CACHE_TOP = 256; 965 966 typedef ResourceHashtable<InstanceKlass*, DumperClassCacheTableEntry*, 967 TABLE_SIZE, AnyObj::C_HEAP, mtServiceability> PtrTable; 968 PtrTable* _ptrs; 969 970 // Single-slot cache to handle the major case of objects of the same 971 // class back-to-back, e.g. from T[]. 972 InstanceKlass* _last_ik; 973 DumperClassCacheTableEntry* _last_entry; 974 975 void unlink_all(PtrTable* table) { 976 class CleanupEntry: StackObj { 977 public: 978 bool do_entry(InstanceKlass*& key, DumperClassCacheTableEntry*& entry) { 979 delete entry; 980 return true; 981 } 982 } cleanup; 983 table->unlink(&cleanup); 984 } 985 986 public: 987 DumperClassCacheTableEntry* lookup_or_create(InstanceKlass* ik) { 988 if (_last_ik == ik) { 989 return _last_entry; 990 } 991 992 DumperClassCacheTableEntry* entry; 993 DumperClassCacheTableEntry** from_cache = _ptrs->get(ik); 994 if (from_cache == nullptr) { 995 entry = new DumperClassCacheTableEntry(); 996 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) { 997 if (!fld.access_flags().is_static()) { 998 InlineKlass* inlineKlass = nullptr; 999 if (DumperSupport::is_inlined_field(fld.field_descriptor())) { 1000 inlineKlass = DumperSupport::get_inlined_field_klass(fld.field_descriptor()); 1001 entry->push_sig_start_inlined(); 1002 entry->_instance_size += DumperSupport::instance_size(inlineKlass); 1003 } else { 1004 Symbol* sig = fld.signature(); 1005 entry->_sigs_start.push(sig->char_at(0)); 1006 entry->_instance_size += DumperSupport::sig2size(sig); 1007 } 1008 entry->_inline_klasses.push(inlineKlass); 1009 entry->_offsets.push(fld.offset()); 1010 entry->_entries++; 1011 } 1012 } 1013 1014 if (_ptrs->number_of_entries() >= CACHE_TOP) { 1015 // We do not track the individual hit rates for table entries. 1016 // Purge the entire table, and let the cache catch up with new 1017 // distribution. 1018 unlink_all(_ptrs); 1019 } 1020 1021 _ptrs->put(ik, entry); 1022 } else { 1023 entry = *from_cache; 1024 } 1025 1026 // Remember for single-slot cache. 1027 _last_ik = ik; 1028 _last_entry = entry; 1029 1030 return entry; 1031 } 1032 1033 DumperClassCacheTable() : _ptrs(new (mtServiceability) PtrTable), _last_ik(nullptr), _last_entry(nullptr) {} 1034 1035 ~DumperClassCacheTable() { 1036 unlink_all(_ptrs); 1037 delete _ptrs; 1038 } 1039 }; 1040 1041 // write a header of the given type 1042 void DumperSupport:: write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len) { 1043 writer->write_u1(tag); 1044 writer->write_u4(0); // current ticks 1045 writer->write_u4(len); 1046 } 1047 1048 // returns hprof tag for the given type signature 1049 hprofTag DumperSupport::sig2tag(Symbol* sig) { 1050 switch (sig->char_at(0)) { 1051 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT; 1052 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT; 1053 case JVM_SIGNATURE_BYTE : return HPROF_BYTE; 1054 case JVM_SIGNATURE_CHAR : return HPROF_CHAR; 1055 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT; 1056 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE; 1057 case JVM_SIGNATURE_INT : return HPROF_INT; 1058 case JVM_SIGNATURE_LONG : return HPROF_LONG; 1059 case JVM_SIGNATURE_SHORT : return HPROF_SHORT; 1060 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN; 1061 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 1062 } 1063 } 1064 1065 hprofTag DumperSupport::type2tag(BasicType type) { 1066 switch (type) { 1067 case T_BYTE : return HPROF_BYTE; 1068 case T_CHAR : return HPROF_CHAR; 1069 case T_FLOAT : return HPROF_FLOAT; 1070 case T_DOUBLE : return HPROF_DOUBLE; 1071 case T_INT : return HPROF_INT; 1072 case T_LONG : return HPROF_LONG; 1073 case T_SHORT : return HPROF_SHORT; 1074 case T_BOOLEAN : return HPROF_BOOLEAN; 1075 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 1076 } 1077 } 1078 1079 u4 DumperSupport::sig2size(Symbol* sig) { 1080 switch (sig->char_at(0)) { 1081 case JVM_SIGNATURE_CLASS: 1082 case JVM_SIGNATURE_ARRAY: return sizeof(address); 1083 case JVM_SIGNATURE_BOOLEAN: 1084 case JVM_SIGNATURE_BYTE: return 1; 1085 case JVM_SIGNATURE_SHORT: 1086 case JVM_SIGNATURE_CHAR: return 2; 1087 case JVM_SIGNATURE_INT: 1088 case JVM_SIGNATURE_FLOAT: return 4; 1089 case JVM_SIGNATURE_LONG: 1090 case JVM_SIGNATURE_DOUBLE: return 8; 1091 default: ShouldNotReachHere(); /* to shut up compiler */ return 0; 1092 } 1093 } 1094 1095 template<typename T, typename F> T bit_cast(F from) { // replace with the real thing when we can use c++20 1096 T to; 1097 static_assert(sizeof(to) == sizeof(from), "must be of the same size"); 1098 memcpy(&to, &from, sizeof(to)); 1099 return to; 1100 } 1101 1102 // dump a jfloat 1103 void DumperSupport::dump_float(AbstractDumpWriter* writer, jfloat f) { 1104 if (g_isnan(f)) { 1105 writer->write_u4(0x7fc00000); // collapsing NaNs 1106 } else { 1107 writer->write_u4(bit_cast<u4>(f)); 1108 } 1109 } 1110 1111 // dump a jdouble 1112 void DumperSupport::dump_double(AbstractDumpWriter* writer, jdouble d) { 1113 if (g_isnan(d)) { 1114 writer->write_u8(0x7ff80000ull << 32); // collapsing NaNs 1115 } else { 1116 writer->write_u8(bit_cast<u8>(d)); 1117 } 1118 } 1119 1120 1121 // dumps the raw value of the given field 1122 void DumperSupport::dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset) { 1123 switch (type) { 1124 case JVM_SIGNATURE_CLASS : 1125 case JVM_SIGNATURE_ARRAY : { 1126 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF | AS_NO_KEEPALIVE>(offset); 1127 o = mask_dormant_archived_object(o, obj); 1128 assert(oopDesc::is_oop_or_null(o), "Expected an oop or nullptr at " PTR_FORMAT, p2i(o)); 1129 writer->write_objectID(o); 1130 break; 1131 } 1132 case JVM_SIGNATURE_BYTE : { 1133 jbyte b = obj->byte_field(offset); 1134 writer->write_u1(b); 1135 break; 1136 } 1137 case JVM_SIGNATURE_CHAR : { 1138 jchar c = obj->char_field(offset); 1139 writer->write_u2(c); 1140 break; 1141 } 1142 case JVM_SIGNATURE_SHORT : { 1143 jshort s = obj->short_field(offset); 1144 writer->write_u2(s); 1145 break; 1146 } 1147 case JVM_SIGNATURE_FLOAT : { 1148 jfloat f = obj->float_field(offset); 1149 dump_float(writer, f); 1150 break; 1151 } 1152 case JVM_SIGNATURE_DOUBLE : { 1153 jdouble d = obj->double_field(offset); 1154 dump_double(writer, d); 1155 break; 1156 } 1157 case JVM_SIGNATURE_INT : { 1158 jint i = obj->int_field(offset); 1159 writer->write_u4(i); 1160 break; 1161 } 1162 case JVM_SIGNATURE_LONG : { 1163 jlong l = obj->long_field(offset); 1164 writer->write_u8(l); 1165 break; 1166 } 1167 case JVM_SIGNATURE_BOOLEAN : { 1168 jboolean b = obj->bool_field(offset); 1169 writer->write_u1(b); 1170 break; 1171 } 1172 default : { 1173 ShouldNotReachHere(); 1174 break; 1175 } 1176 } 1177 } 1178 1179 // calculates the total size of the all fields of the given class. 1180 u4 DumperSupport::instance_size(InstanceKlass* ik, DumperClassCacheTableEntry* class_cache_entry) { 1181 if (class_cache_entry != nullptr) { 1182 return class_cache_entry->instance_size(); 1183 } else { 1184 u4 size = 0; 1185 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) { 1186 if (!fld.access_flags().is_static()) { 1187 if (is_inlined_field(fld.field_descriptor())) { 1188 size += instance_size(get_inlined_field_klass(fld.field_descriptor())); 1189 } else { 1190 size += sig2size(fld.signature()); 1191 } 1192 } 1193 } 1194 return size; 1195 } 1196 } 1197 1198 u4 DumperSupport::get_static_fields_size(InstanceKlass* ik, u2& field_count) { 1199 field_count = 0; 1200 u4 size = 0; 1201 1202 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) { 1203 if (fldc.access_flags().is_static()) { 1204 assert(!is_inlined_field(fldc.field_descriptor()), "static fields cannot be inlined"); 1205 1206 field_count++; 1207 size += sig2size(fldc.signature()); 1208 } 1209 } 1210 1211 // Add in resolved_references which is referenced by the cpCache 1212 // The resolved_references is an array per InstanceKlass holding the 1213 // strings and other oops resolved from the constant pool. 1214 oop resolved_references = ik->constants()->resolved_references_or_null(); 1215 if (resolved_references != nullptr) { 1216 field_count++; 1217 size += sizeof(address); 1218 1219 // Add in the resolved_references of the used previous versions of the class 1220 // in the case of RedefineClasses 1221 InstanceKlass* prev = ik->previous_versions(); 1222 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) { 1223 field_count++; 1224 size += sizeof(address); 1225 prev = prev->previous_versions(); 1226 } 1227 } 1228 1229 // We write the value itself plus a name and a one byte type tag per field. 1230 return checked_cast<u4>(size + field_count * (sizeof(address) + 1)); 1231 } 1232 1233 // dumps static fields of the given class 1234 void DumperSupport::dump_static_fields(AbstractDumpWriter* writer, Klass* k) { 1235 InstanceKlass* ik = InstanceKlass::cast(k); 1236 1237 // dump the field descriptors and raw values 1238 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) { 1239 if (fld.access_flags().is_static()) { 1240 assert(!is_inlined_field(fld.field_descriptor()), "static fields cannot be inlined"); 1241 1242 Symbol* sig = fld.signature(); 1243 1244 writer->write_symbolID(fld.name()); // name 1245 writer->write_u1(sig2tag(sig)); // type 1246 1247 // value 1248 dump_field_value(writer, sig->char_at(0), ik->java_mirror(), fld.offset()); 1249 } 1250 } 1251 1252 // Add resolved_references for each class that has them 1253 oop resolved_references = ik->constants()->resolved_references_or_null(); 1254 if (resolved_references != nullptr) { 1255 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 1256 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 1257 writer->write_objectID(resolved_references); 1258 1259 // Also write any previous versions 1260 InstanceKlass* prev = ik->previous_versions(); 1261 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) { 1262 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 1263 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 1264 writer->write_objectID(prev->constants()->resolved_references()); 1265 prev = prev->previous_versions(); 1266 } 1267 } 1268 } 1269 1270 // dump the raw values of the instance fields of the given identity or inlined object; 1271 // for identity objects offset is 0 and 'klass' is o->klass(), 1272 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class. 1273 void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) { 1274 assert(class_cache_entry != nullptr, "Pre-condition: must be provided"); 1275 for (int idx = 0; idx < class_cache_entry->field_count(); idx++) { 1276 if (class_cache_entry->is_inlined(idx)) { 1277 InlineKlass* field_klass = class_cache_entry->inline_klass(idx); 1278 int fields_offset = offset + (class_cache_entry->offset(idx) - field_klass->first_field_offset()); 1279 DumperClassCacheTableEntry* inline_class_cache_entry = class_cache->lookup_or_create(field_klass); 1280 dump_inlined_object_fields(writer, o, fields_offset, class_cache, inline_class_cache_entry); 1281 } else { 1282 dump_field_value(writer, class_cache_entry->sig_start(idx), o, class_cache_entry->offset(idx)); 1283 } 1284 } 1285 } 1286 1287 void DumperSupport::dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, DumperClassCacheTable* class_cache, DumperClassCacheTableEntry* class_cache_entry) { 1288 // the object is inlined, so all its fields are stored without headers. 1289 dump_instance_fields(writer, o, offset, class_cache, class_cache_entry); 1290 } 1291 1292 // gets the count of the instance fields for a given class 1293 u2 DumperSupport::get_instance_fields_count(InstanceKlass* ik) { 1294 u2 field_count = 0; 1295 1296 for (JavaFieldStream fldc(ik); !fldc.done(); fldc.next()) { 1297 if (!fldc.access_flags().is_static()) { 1298 if (is_inlined_field(fldc.field_descriptor())) { 1299 // add "synthetic" fields for inlined fields. 1300 field_count += get_instance_fields_count(get_inlined_field_klass(fldc.field_descriptor())); 1301 } else { 1302 field_count++; 1303 } 1304 } 1305 } 1306 1307 return field_count; 1308 } 1309 1310 // dumps the definition of the instance fields for a given class 1311 // inlined_fields_id is not-nullptr for inlined fields (to get synthetic field name IDs 1312 // by using InlinedObjects::get_next_string_id()). 1313 void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* ik, uintx* inlined_fields_id) { 1314 // inlined_fields_id != nullptr means ik is a class of inlined field. 1315 // Inlined field id pointer for this class; lazyly initialized 1316 // if the class has inlined field(s) and the caller didn't provide inlined_fields_id. 1317 uintx *this_klass_inlined_fields_id = inlined_fields_id; 1318 uintx inlined_id = 0; 1319 1320 // dump the field descriptors 1321 for (JavaFieldStream fld(ik); !fld.done(); fld.next()) { 1322 if (!fld.access_flags().is_static()) { 1323 if (is_inlined_field(fld.field_descriptor())) { 1324 // dump "synthetic" fields for inlined fields. 1325 if (this_klass_inlined_fields_id == nullptr) { 1326 inlined_id = InlinedObjects::get_instance()->get_base_index_for(ik); 1327 this_klass_inlined_fields_id = &inlined_id; 1328 } 1329 dump_instance_field_descriptors(writer, get_inlined_field_klass(fld.field_descriptor()), this_klass_inlined_fields_id); 1330 } else { 1331 Symbol* sig = fld.signature(); 1332 Symbol* name = nullptr; 1333 // Use inlined_fields_id provided by caller. 1334 if (inlined_fields_id != nullptr) { 1335 uintx name_id = InlinedObjects::get_instance()->get_next_string_id(*inlined_fields_id); 1336 1337 // name_id == 0 is returned on error. use original field signature. 1338 if (name_id != 0) { 1339 *inlined_fields_id = name_id; 1340 name = reinterpret_cast<Symbol*>(name_id); 1341 } 1342 } 1343 if (name == nullptr) { 1344 name = fld.name(); 1345 } 1346 1347 writer->write_symbolID(name); // name 1348 writer->write_u1(sig2tag(sig)); // type 1349 } 1350 } 1351 } 1352 } 1353 1354 // creates HPROF_GC_INSTANCE_DUMP record for the given object 1355 void DumperSupport::dump_instance(AbstractDumpWriter* writer, oop o, DumperClassCacheTable* class_cache) { 1356 InstanceKlass* ik = InstanceKlass::cast(o->klass()); 1357 1358 DumperClassCacheTableEntry* cache_entry = class_cache->lookup_or_create(ik); 1359 1360 u4 is = instance_size(ik, cache_entry); 1361 u4 size = 1 + sizeof(address) + 4 + sizeof(address) + 4 + is; 1362 1363 writer->start_sub_record(HPROF_GC_INSTANCE_DUMP, size); 1364 writer->write_objectID(o); 1365 writer->write_u4(STACK_TRACE_ID); 1366 1367 // class ID 1368 writer->write_classID(ik); 1369 1370 // number of bytes that follow 1371 writer->write_u4(is); 1372 1373 // field values 1374 dump_instance_fields(writer, o, 0, class_cache, cache_entry); 1375 1376 writer->end_sub_record(); 1377 } 1378 1379 // creates HPROF_GC_CLASS_DUMP record for the given instance class 1380 void DumperSupport::dump_instance_class(AbstractDumpWriter* writer, Klass* k) { 1381 InstanceKlass* ik = InstanceKlass::cast(k); 1382 1383 // We can safepoint and do a heap dump at a point where we have a Klass, 1384 // but no java mirror class has been setup for it. So we need to check 1385 // that the class is at least loaded, to avoid crash from a null mirror. 1386 if (!ik->is_loaded()) { 1387 return; 1388 } 1389 1390 u2 static_fields_count = 0; 1391 u4 static_size = get_static_fields_size(ik, static_fields_count); 1392 u2 instance_fields_count = get_instance_fields_count(ik); 1393 u4 instance_fields_size = instance_fields_count * (sizeof(address) + 1); 1394 u4 size = checked_cast<u4>(1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + static_size + 2 + instance_fields_size); 1395 1396 writer->start_sub_record(HPROF_GC_CLASS_DUMP, size); 1397 1398 // class ID 1399 writer->write_classID(ik); 1400 writer->write_u4(STACK_TRACE_ID); 1401 1402 // super class ID 1403 InstanceKlass* java_super = ik->java_super(); 1404 if (java_super == nullptr) { 1405 writer->write_objectID(oop(nullptr)); 1406 } else { 1407 writer->write_classID(java_super); 1408 } 1409 1410 writer->write_objectID(ik->class_loader()); 1411 writer->write_objectID(ik->signers()); 1412 writer->write_objectID(ik->protection_domain()); 1413 1414 // reserved 1415 writer->write_objectID(oop(nullptr)); 1416 writer->write_objectID(oop(nullptr)); 1417 1418 // instance size 1419 writer->write_u4(HeapWordSize * ik->size_helper()); 1420 1421 // size of constant pool - ignored by HAT 1.1 1422 writer->write_u2(0); 1423 1424 // static fields 1425 writer->write_u2(static_fields_count); 1426 dump_static_fields(writer, ik); 1427 1428 // description of instance fields 1429 writer->write_u2(instance_fields_count); 1430 dump_instance_field_descriptors(writer, ik); 1431 1432 writer->end_sub_record(); 1433 } 1434 1435 // creates HPROF_GC_CLASS_DUMP record for the given array class 1436 void DumperSupport::dump_array_class(AbstractDumpWriter* writer, Klass* k) { 1437 InstanceKlass* ik = nullptr; // bottom class for object arrays, null for primitive type arrays 1438 if (k->is_objArray_klass()) { 1439 Klass *bk = ObjArrayKlass::cast(k)->bottom_klass(); 1440 assert(bk != nullptr, "checking"); 1441 if (bk->is_instance_klass()) { 1442 ik = InstanceKlass::cast(bk); 1443 } 1444 } 1445 1446 u4 size = 1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + 2; 1447 writer->start_sub_record(HPROF_GC_CLASS_DUMP, size); 1448 writer->write_classID(k); 1449 writer->write_u4(STACK_TRACE_ID); 1450 1451 // super class of array classes is java.lang.Object 1452 InstanceKlass* java_super = k->java_super(); 1453 assert(java_super != nullptr, "checking"); 1454 writer->write_classID(java_super); 1455 1456 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->class_loader()); 1457 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->signers()); 1458 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->protection_domain()); 1459 1460 writer->write_objectID(oop(nullptr)); // reserved 1461 writer->write_objectID(oop(nullptr)); 1462 writer->write_u4(0); // instance size 1463 writer->write_u2(0); // constant pool 1464 writer->write_u2(0); // static fields 1465 writer->write_u2(0); // instance fields 1466 1467 writer->end_sub_record(); 1468 1469 } 1470 1471 // Hprof uses an u4 as record length field, 1472 // which means we need to truncate arrays that are too long. 1473 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size) { 1474 int length = array->length(); 1475 1476 size_t length_in_bytes = (size_t)length * type_size; 1477 uint max_bytes = max_juint - header_size; 1478 1479 if (length_in_bytes > max_bytes) { 1480 length = max_bytes / type_size; 1481 length_in_bytes = (size_t)length * type_size; 1482 1483 BasicType type = ArrayKlass::cast(array->klass())->element_type(); 1484 warning("cannot dump array of type %s[] with length %d; truncating to length %d", 1485 type2name_tab[type], array->length(), length); 1486 } 1487 return length; 1488 } 1489 1490 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) { 1491 BasicType type = ArrayKlass::cast(array->klass())->element_type(); 1492 assert((type >= T_BOOLEAN && type <= T_OBJECT) || type == T_PRIMITIVE_OBJECT, "invalid array element type"); 1493 int type_size; 1494 if (type == T_OBJECT) { 1495 type_size = sizeof(address); 1496 } else if (type == T_PRIMITIVE_OBJECT) { 1497 // TODO: FIXME 1498 fatal("Not supported yet"); // FIXME: JDK-8325678 1499 } else { 1500 type_size = type2aelembytes(type); 1501 } 1502 1503 return calculate_array_max_length(writer, array, type_size, header_size); 1504 } 1505 1506 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 1507 void DumperSupport::dump_object_array(AbstractDumpWriter* writer, objArrayOop array) { 1508 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID) 1509 short header_size = 1 + 2 * 4 + 2 * sizeof(address); 1510 int length = calculate_array_max_length(writer, array, header_size); 1511 u4 size = checked_cast<u4>(header_size + length * sizeof(address)); 1512 1513 writer->start_sub_record(HPROF_GC_OBJ_ARRAY_DUMP, size); 1514 writer->write_objectID(array); 1515 writer->write_u4(STACK_TRACE_ID); 1516 writer->write_u4(length); 1517 1518 // array class ID 1519 writer->write_classID(array->klass()); 1520 1521 // [id]* elements 1522 for (int index = 0; index < length; index++) { 1523 oop o = array->obj_at(index); 1524 o = mask_dormant_archived_object(o, array); 1525 writer->write_objectID(o); 1526 } 1527 1528 writer->end_sub_record(); 1529 } 1530 1531 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array 1532 void DumperSupport::dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array, DumperClassCacheTable* class_cache) { 1533 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass()); 1534 InlineKlass* element_klass = array_klass->element_klass(); 1535 int element_size = instance_size(element_klass); 1536 /* id array object ID 1537 * u4 stack trace serial number 1538 * u4 number of elements 1539 * u1 element type 1540 */ 1541 short header_size = 1 + sizeof(address) + 2 * 4 + 1; 1542 1543 // TODO: use T_SHORT/T_INT/T_LONG if needed to avoid truncation 1544 BasicType type = T_BYTE; 1545 int type_size = type2aelembytes(type); 1546 int length = calculate_array_max_length(writer, array, element_size, header_size); 1547 u4 length_in_bytes = (u4)(length * element_size); 1548 u4 size = header_size + length_in_bytes; 1549 1550 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size); 1551 writer->write_objectID(array); 1552 writer->write_u4(STACK_TRACE_ID); 1553 // TODO: round up array length for T_SHORT/T_INT/T_LONG 1554 writer->write_u4(length * element_size); 1555 writer->write_u1(type2tag(type)); 1556 1557 for (int index = 0; index < length; index++) { 1558 // need offset in the holder to read inlined object. calculate it from flatArrayOop::value_at_addr() 1559 int offset = (int)((address)array->value_at_addr(index, array_klass->layout_helper()) 1560 - cast_from_oop<address>(array)); 1561 DumperClassCacheTableEntry* class_cache_entry = class_cache->lookup_or_create(element_klass); 1562 dump_inlined_object_fields(writer, array, offset, class_cache, class_cache_entry); 1563 } 1564 1565 // TODO: write padding bytes for T_SHORT/T_INT/T_LONG 1566 1567 InlinedObjects::get_instance()->add_flat_array(array); 1568 1569 writer->end_sub_record(); 1570 } 1571 1572 #define WRITE_ARRAY(Array, Type, Size, Length) \ 1573 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); } 1574 1575 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 1576 void DumperSupport::dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array) { 1577 BasicType type = TypeArrayKlass::cast(array->klass())->element_type(); 1578 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) 1579 short header_size = 2 * 1 + 2 * 4 + sizeof(address); 1580 1581 int length = calculate_array_max_length(writer, array, header_size); 1582 int type_size = type2aelembytes(type); 1583 u4 length_in_bytes = (u4)length * type_size; 1584 u4 size = header_size + length_in_bytes; 1585 1586 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size); 1587 writer->write_objectID(array); 1588 writer->write_u4(STACK_TRACE_ID); 1589 writer->write_u4(length); 1590 writer->write_u1(type2tag(type)); 1591 1592 // nothing to copy 1593 if (length == 0) { 1594 writer->end_sub_record(); 1595 return; 1596 } 1597 1598 // If the byte ordering is big endian then we can copy most types directly 1599 1600 switch (type) { 1601 case T_INT : { 1602 if (Endian::is_Java_byte_ordering_different()) { 1603 WRITE_ARRAY(array, int, u4, length); 1604 } else { 1605 writer->write_raw(array->int_at_addr(0), length_in_bytes); 1606 } 1607 break; 1608 } 1609 case T_BYTE : { 1610 writer->write_raw(array->byte_at_addr(0), length_in_bytes); 1611 break; 1612 } 1613 case T_CHAR : { 1614 if (Endian::is_Java_byte_ordering_different()) { 1615 WRITE_ARRAY(array, char, u2, length); 1616 } else { 1617 writer->write_raw(array->char_at_addr(0), length_in_bytes); 1618 } 1619 break; 1620 } 1621 case T_SHORT : { 1622 if (Endian::is_Java_byte_ordering_different()) { 1623 WRITE_ARRAY(array, short, u2, length); 1624 } else { 1625 writer->write_raw(array->short_at_addr(0), length_in_bytes); 1626 } 1627 break; 1628 } 1629 case T_BOOLEAN : { 1630 if (Endian::is_Java_byte_ordering_different()) { 1631 WRITE_ARRAY(array, bool, u1, length); 1632 } else { 1633 writer->write_raw(array->bool_at_addr(0), length_in_bytes); 1634 } 1635 break; 1636 } 1637 case T_LONG : { 1638 if (Endian::is_Java_byte_ordering_different()) { 1639 WRITE_ARRAY(array, long, u8, length); 1640 } else { 1641 writer->write_raw(array->long_at_addr(0), length_in_bytes); 1642 } 1643 break; 1644 } 1645 1646 // handle float/doubles in a special value to ensure than NaNs are 1647 // written correctly. TO DO: Check if we can avoid this on processors that 1648 // use IEEE 754. 1649 1650 case T_FLOAT : { 1651 for (int i = 0; i < length; i++) { 1652 dump_float(writer, array->float_at(i)); 1653 } 1654 break; 1655 } 1656 case T_DOUBLE : { 1657 for (int i = 0; i < length; i++) { 1658 dump_double(writer, array->double_at(i)); 1659 } 1660 break; 1661 } 1662 default : ShouldNotReachHere(); 1663 } 1664 1665 writer->end_sub_record(); 1666 } 1667 1668 // create a HPROF_FRAME record of the given Method* and bci 1669 void DumperSupport::dump_stack_frame(AbstractDumpWriter* writer, 1670 int frame_serial_num, 1671 int class_serial_num, 1672 Method* m, 1673 int bci) { 1674 int line_number; 1675 if (m->is_native()) { 1676 line_number = -3; // native frame 1677 } else { 1678 line_number = m->line_number_from_bci(bci); 1679 } 1680 1681 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4)); 1682 writer->write_id(frame_serial_num); // frame serial number 1683 writer->write_symbolID(m->name()); // method's name 1684 writer->write_symbolID(m->signature()); // method's signature 1685 1686 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass"); 1687 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name 1688 writer->write_u4(class_serial_num); // class serial number 1689 writer->write_u4((u4) line_number); // line number 1690 } 1691 1692 1693 class InlinedFieldNameDumper : public LockedClassesDo { 1694 public: 1695 typedef void (*Callback)(InlinedObjects *owner, const Klass *klass, uintx base_index, int count); 1696 1697 private: 1698 AbstractDumpWriter* _writer; 1699 InlinedObjects *_owner; 1700 Callback _callback; 1701 uintx _index; 1702 1703 void dump_inlined_field_names(GrowableArray<Symbol*>* super_names, Symbol* field_name, InlineKlass* klass) { 1704 super_names->push(field_name); 1705 for (HierarchicalFieldStream<JavaFieldStream> fld(klass); !fld.done(); fld.next()) { 1706 if (!fld.access_flags().is_static()) { 1707 if (DumperSupport::is_inlined_field(fld.field_descriptor())) { 1708 dump_inlined_field_names(super_names, fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor())); 1709 } else { 1710 // get next string ID. 1711 uintx next_index = _owner->get_next_string_id(_index); 1712 if (next_index == 0) { 1713 // something went wrong (overflow?) 1714 // stop generation; the rest of inlined objects will have original field names. 1715 return; 1716 } 1717 _index = next_index; 1718 1719 // Calculate length. 1720 int len = fld.name()->utf8_length(); 1721 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) { 1722 len += (*it)->utf8_length() + 1; // +1 for ".". 1723 } 1724 1725 DumperSupport::write_header(_writer, HPROF_UTF8, oopSize + len); 1726 _writer->write_symbolID(reinterpret_cast<Symbol*>(_index)); 1727 // Write the string value. 1728 // 1) super_names. 1729 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) { 1730 _writer->write_raw((*it)->bytes(), (*it)->utf8_length()); 1731 _writer->write_u1('.'); 1732 } 1733 // 2) field name. 1734 _writer->write_raw(fld.name()->bytes(), fld.name()->utf8_length()); 1735 } 1736 } 1737 } 1738 super_names->pop(); 1739 } 1740 1741 void dump_inlined_field_names(Symbol* field_name, InlineKlass* field_klass) { 1742 GrowableArray<Symbol*> super_names(4, mtServiceability); 1743 dump_inlined_field_names(&super_names, field_name, field_klass); 1744 } 1745 1746 public: 1747 InlinedFieldNameDumper(AbstractDumpWriter* writer, InlinedObjects* owner, Callback callback) 1748 : _writer(writer), _owner(owner), _callback(callback), _index(0) { 1749 } 1750 1751 void do_klass(Klass* k) { 1752 if (!k->is_instance_klass()) { 1753 return; 1754 } 1755 InstanceKlass* ik = InstanceKlass::cast(k); 1756 // if (ik->has_inline_type_fields()) { 1757 // return; 1758 // } 1759 1760 uintx base_index = _index; 1761 int count = 0; 1762 1763 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) { 1764 if (!fld.access_flags().is_static()) { 1765 if (DumperSupport::is_inlined_field(fld.field_descriptor())) { 1766 dump_inlined_field_names(fld.name(), DumperSupport::get_inlined_field_klass(fld.field_descriptor())); 1767 count++; 1768 } 1769 } 1770 } 1771 1772 if (count != 0) { 1773 _callback(_owner, k, base_index, count); 1774 } 1775 } 1776 }; 1777 1778 class InlinedFieldsDumper : public LockedClassesDo { 1779 private: 1780 AbstractDumpWriter* _writer; 1781 1782 public: 1783 InlinedFieldsDumper(AbstractDumpWriter* writer) : _writer(writer) {} 1784 1785 void do_klass(Klass* k) { 1786 if (!k->is_instance_klass()) { 1787 return; 1788 } 1789 InstanceKlass* ik = InstanceKlass::cast(k); 1790 // if (ik->has_inline_type_fields()) { 1791 // return; 1792 // } 1793 1794 // We can be at a point where java mirror does not exist yet. 1795 // So we need to check that the class is at least loaded, to avoid crash from a null mirror. 1796 if (!ik->is_loaded()) { 1797 return; 1798 } 1799 1800 u2 inlined_count = 0; 1801 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) { 1802 if (!fld.access_flags().is_static()) { 1803 if (DumperSupport::is_inlined_field(fld.field_descriptor())) { 1804 inlined_count++; 1805 } 1806 } 1807 } 1808 if (inlined_count != 0) { 1809 _writer->write_u1(HPROF_CLASS_WITH_INLINED_FIELDS); 1810 1811 // class ID 1812 _writer->write_classID(ik); 1813 // number of inlined fields 1814 _writer->write_u2(inlined_count); 1815 u2 index = 0; 1816 for (HierarchicalFieldStream<JavaFieldStream> fld(ik); !fld.done(); fld.next()) { 1817 if (!fld.access_flags().is_static()) { 1818 if (DumperSupport::is_inlined_field(fld.field_descriptor())) { 1819 // inlined field index 1820 _writer->write_u2(index); 1821 // synthetic field count 1822 u2 field_count = DumperSupport::get_instance_fields_count(DumperSupport::get_inlined_field_klass(fld.field_descriptor())); 1823 _writer->write_u2(field_count); 1824 // original field name 1825 _writer->write_symbolID(fld.name()); 1826 // inlined field class ID 1827 _writer->write_classID(DumperSupport::get_inlined_field_klass(fld.field_descriptor())); 1828 1829 index += field_count; 1830 } else { 1831 index++; 1832 } 1833 } 1834 } 1835 } 1836 } 1837 }; 1838 1839 1840 void InlinedObjects::init() { 1841 _instance = this; 1842 1843 struct Closure : public SymbolClosure { 1844 uintx _min_id = max_uintx; 1845 uintx _max_id = 0; 1846 Closure() : _min_id(max_uintx), _max_id(0) {} 1847 1848 void do_symbol(Symbol** p) { 1849 uintx val = reinterpret_cast<uintx>(*p); 1850 if (val < _min_id) { 1851 _min_id = val; 1852 } 1853 if (val > _max_id) { 1854 _max_id = val; 1855 } 1856 } 1857 } closure; 1858 1859 SymbolTable::symbols_do(&closure); 1860 1861 _min_string_id = closure._min_id; 1862 _max_string_id = closure._max_id; 1863 } 1864 1865 void InlinedObjects::release() { 1866 _instance = nullptr; 1867 1868 if (_inlined_field_map != nullptr) { 1869 delete _inlined_field_map; 1870 _inlined_field_map = nullptr; 1871 } 1872 if (_flat_arrays != nullptr) { 1873 delete _flat_arrays; 1874 _flat_arrays = nullptr; 1875 } 1876 } 1877 1878 void InlinedObjects::inlined_field_names_callback(InlinedObjects* _this, const Klass* klass, uintx base_index, int count) { 1879 if (_this->_inlined_field_map == nullptr) { 1880 _this->_inlined_field_map = new (mtServiceability) GrowableArray<ClassInlinedFields>(100, mtServiceability); 1881 } 1882 _this->_inlined_field_map->append(ClassInlinedFields(klass, base_index)); 1883 1884 // counters for dumping classes with inlined fields 1885 _this->_classes_count++; 1886 _this->_inlined_fields_count += count; 1887 } 1888 1889 void InlinedObjects::dump_inlined_field_names(AbstractDumpWriter* writer) { 1890 InlinedFieldNameDumper nameDumper(writer, this, inlined_field_names_callback); 1891 ClassLoaderDataGraph::classes_do(&nameDumper); 1892 1893 if (_inlined_field_map != nullptr) { 1894 // prepare the map for get_base_index_for(). 1895 _inlined_field_map->sort(ClassInlinedFields::compare); 1896 } 1897 } 1898 1899 uintx InlinedObjects::get_base_index_for(Klass* k) { 1900 if (_inlined_field_map != nullptr) { 1901 bool found = false; 1902 int idx = _inlined_field_map->find_sorted<ClassInlinedFields, ClassInlinedFields::compare>(ClassInlinedFields(k, 0), found); 1903 if (found) { 1904 return _inlined_field_map->at(idx).base_index; 1905 } 1906 } 1907 1908 // return max_uintx, so get_next_string_id returns 0. 1909 return max_uintx; 1910 } 1911 1912 uintx InlinedObjects::get_next_string_id(uintx id) { 1913 if (++id == _min_string_id) { 1914 return _max_string_id + 1; 1915 } 1916 return id; 1917 } 1918 1919 void InlinedObjects::dump_classed_with_inlined_fields(AbstractDumpWriter* writer) { 1920 if (_classes_count != 0) { 1921 // Record for each class contains tag(u1), class ID and count(u2) 1922 // for each inlined field index(u2), synthetic fields count(u2), original field name and class ID 1923 int size = _classes_count * (1 + sizeof(address) + 2) 1924 + _inlined_fields_count * (2 + 2 + sizeof(address) + sizeof(address)); 1925 DumperSupport::write_header(writer, HPROF_INLINED_FIELDS, (u4)size); 1926 1927 InlinedFieldsDumper dumper(writer); 1928 ClassLoaderDataGraph::classes_do(&dumper); 1929 } 1930 } 1931 1932 void InlinedObjects::add_flat_array(oop array) { 1933 if (_flat_arrays == nullptr) { 1934 _flat_arrays = new (mtServiceability) GrowableArray<oop>(100, mtServiceability); 1935 } 1936 _flat_arrays->append(array); 1937 } 1938 1939 void InlinedObjects::dump_flat_arrays(AbstractDumpWriter* writer) { 1940 if (_flat_arrays != nullptr) { 1941 // For each flat array the record contains tag (u1), object ID and class ID. 1942 int size = _flat_arrays->length() * (1 + sizeof(address) + sizeof(address)); 1943 1944 DumperSupport::write_header(writer, HPROF_FLAT_ARRAYS, (u4)size); 1945 for (GrowableArrayIterator<oop> it = _flat_arrays->begin(); it != _flat_arrays->end(); ++it) { 1946 flatArrayOop array = flatArrayOop(*it); 1947 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass()); 1948 InlineKlass* element_klass = array_klass->element_klass(); 1949 writer->write_u1(HPROF_FLAT_ARRAY); 1950 writer->write_objectID(array); 1951 writer->write_classID(element_klass); 1952 } 1953 } 1954 } 1955 1956 1957 // Support class used to generate HPROF_UTF8 records from the entries in the 1958 // SymbolTable. 1959 1960 class SymbolTableDumper : public SymbolClosure { 1961 private: 1962 AbstractDumpWriter* _writer; 1963 AbstractDumpWriter* writer() const { return _writer; } 1964 public: 1965 SymbolTableDumper(AbstractDumpWriter* writer) { _writer = writer; } 1966 void do_symbol(Symbol** p); 1967 }; 1968 1969 void SymbolTableDumper::do_symbol(Symbol** p) { 1970 ResourceMark rm; 1971 Symbol* sym = *p; 1972 int len = sym->utf8_length(); 1973 if (len > 0) { 1974 char* s = sym->as_utf8(); 1975 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len); 1976 writer()->write_symbolID(sym); 1977 writer()->write_raw(s, len); 1978 } 1979 } 1980 1981 // Support class used to generate HPROF_GC_CLASS_DUMP records 1982 1983 class ClassDumper : public KlassClosure { 1984 private: 1985 AbstractDumpWriter* _writer; 1986 AbstractDumpWriter* writer() const { return _writer; } 1987 1988 public: 1989 ClassDumper(AbstractDumpWriter* writer) : _writer(writer) {} 1990 1991 void do_klass(Klass* k) { 1992 if (k->is_instance_klass()) { 1993 DumperSupport::dump_instance_class(writer(), k); 1994 } else { 1995 DumperSupport::dump_array_class(writer(), k); 1996 } 1997 } 1998 }; 1999 2000 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records 2001 2002 class JNILocalsDumper : public OopClosure { 2003 private: 2004 AbstractDumpWriter* _writer; 2005 u4 _thread_serial_num; 2006 int _frame_num; 2007 AbstractDumpWriter* writer() const { return _writer; } 2008 public: 2009 JNILocalsDumper(AbstractDumpWriter* writer, u4 thread_serial_num) { 2010 _writer = writer; 2011 _thread_serial_num = thread_serial_num; 2012 _frame_num = -1; // default - empty stack 2013 } 2014 void set_frame_number(int n) { _frame_num = n; } 2015 void do_oop(oop* obj_p); 2016 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 2017 }; 2018 2019 void JNILocalsDumper::do_oop(oop* obj_p) { 2020 // ignore null handles 2021 oop o = *obj_p; 2022 if (o != nullptr) { 2023 u4 size = 1 + sizeof(address) + 4 + 4; 2024 writer()->start_sub_record(HPROF_GC_ROOT_JNI_LOCAL, size); 2025 writer()->write_objectID(o); 2026 writer()->write_u4(_thread_serial_num); 2027 writer()->write_u4((u4)_frame_num); 2028 writer()->end_sub_record(); 2029 } 2030 } 2031 2032 2033 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records 2034 2035 class JNIGlobalsDumper : public OopClosure { 2036 private: 2037 AbstractDumpWriter* _writer; 2038 AbstractDumpWriter* writer() const { return _writer; } 2039 2040 public: 2041 JNIGlobalsDumper(AbstractDumpWriter* writer) { 2042 _writer = writer; 2043 } 2044 void do_oop(oop* obj_p); 2045 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 2046 }; 2047 2048 void JNIGlobalsDumper::do_oop(oop* obj_p) { 2049 oop o = NativeAccess<AS_NO_KEEPALIVE>::oop_load(obj_p); 2050 2051 // ignore these 2052 if (o == nullptr) return; 2053 // we ignore global ref to symbols and other internal objects 2054 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) { 2055 u4 size = 1 + 2 * sizeof(address); 2056 writer()->start_sub_record(HPROF_GC_ROOT_JNI_GLOBAL, size); 2057 writer()->write_objectID(o); 2058 writer()->write_rootID(obj_p); // global ref ID 2059 writer()->end_sub_record(); 2060 } 2061 }; 2062 2063 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records 2064 2065 class StickyClassDumper : public KlassClosure { 2066 private: 2067 AbstractDumpWriter* _writer; 2068 AbstractDumpWriter* writer() const { return _writer; } 2069 public: 2070 StickyClassDumper(AbstractDumpWriter* writer) { 2071 _writer = writer; 2072 } 2073 void do_klass(Klass* k) { 2074 if (k->is_instance_klass()) { 2075 InstanceKlass* ik = InstanceKlass::cast(k); 2076 u4 size = 1 + sizeof(address); 2077 writer()->start_sub_record(HPROF_GC_ROOT_STICKY_CLASS, size); 2078 writer()->write_classID(ik); 2079 writer()->end_sub_record(); 2080 } 2081 } 2082 }; 2083 2084 // Support class used to generate HPROF_GC_ROOT_JAVA_FRAME records. 2085 2086 class JavaStackRefDumper : public StackObj { 2087 private: 2088 AbstractDumpWriter* _writer; 2089 u4 _thread_serial_num; 2090 int _frame_num; 2091 AbstractDumpWriter* writer() const { return _writer; } 2092 public: 2093 JavaStackRefDumper(AbstractDumpWriter* writer, u4 thread_serial_num) 2094 : _writer(writer), _thread_serial_num(thread_serial_num), _frame_num(-1) // default - empty stack 2095 { 2096 } 2097 2098 void set_frame_number(int n) { _frame_num = n; } 2099 2100 void dump_java_stack_refs(StackValueCollection* values); 2101 }; 2102 2103 void JavaStackRefDumper::dump_java_stack_refs(StackValueCollection* values) { 2104 for (int index = 0; index < values->size(); index++) { 2105 if (values->at(index)->type() == T_OBJECT) { 2106 oop o = values->obj_at(index)(); 2107 if (o != nullptr) { 2108 u4 size = 1 + sizeof(address) + 4 + 4; 2109 writer()->start_sub_record(HPROF_GC_ROOT_JAVA_FRAME, size); 2110 writer()->write_objectID(o); 2111 writer()->write_u4(_thread_serial_num); 2112 writer()->write_u4((u4)_frame_num); 2113 writer()->end_sub_record(); 2114 } 2115 } 2116 } 2117 } 2118 2119 // Class to collect, store and dump thread-related data: 2120 // - HPROF_TRACE and HPROF_FRAME records; 2121 // - HPROF_GC_ROOT_THREAD_OBJ/HPROF_GC_ROOT_JAVA_FRAME/HPROF_GC_ROOT_JNI_LOCAL subrecords. 2122 class ThreadDumper : public CHeapObj<mtInternal> { 2123 public: 2124 enum class ThreadType { Platform, MountedVirtual, UnmountedVirtual }; 2125 2126 private: 2127 ThreadType _thread_type; 2128 JavaThread* _java_thread; 2129 oop _thread_oop; 2130 2131 GrowableArray<StackFrameInfo*>* _frames; 2132 // non-null if the thread is OOM thread 2133 Method* _oome_constructor; 2134 int _thread_serial_num; 2135 int _start_frame_serial_num; 2136 2137 vframe* get_top_frame() const; 2138 2139 public: 2140 static bool should_dump_pthread(JavaThread* thread) { 2141 return thread->threadObj() != nullptr && !thread->is_exiting() && !thread->is_hidden_from_external_view(); 2142 } 2143 2144 static bool should_dump_vthread(oop vt) { 2145 return java_lang_VirtualThread::state(vt) != java_lang_VirtualThread::NEW 2146 && java_lang_VirtualThread::state(vt) != java_lang_VirtualThread::TERMINATED; 2147 } 2148 2149 static bool is_vthread_mounted(oop vt) { 2150 // The code should be consistent with the "mounted virtual thread" case 2151 // (VM_HeapDumper::dump_stack_traces(), ThreadDumper::get_top_frame()). 2152 // I.e. virtual thread is mounted if its carrierThread is not null 2153 // and is_vthread_mounted() for the carrier thread returns true. 2154 oop carrier_thread = java_lang_VirtualThread::carrier_thread(vt); 2155 if (carrier_thread == nullptr) { 2156 return false; 2157 } 2158 JavaThread* java_thread = java_lang_Thread::thread(carrier_thread); 2159 return java_thread->is_vthread_mounted(); 2160 } 2161 2162 ThreadDumper(ThreadType thread_type, JavaThread* java_thread, oop thread_oop); 2163 2164 // affects frame_count 2165 void add_oom_frame(Method* oome_constructor) { 2166 assert(_start_frame_serial_num == 0, "add_oom_frame cannot be called after init_serial_nums"); 2167 _oome_constructor = oome_constructor; 2168 } 2169 2170 void init_serial_nums(volatile int* thread_counter, volatile int* frame_counter) { 2171 assert(_start_frame_serial_num == 0, "already initialized"); 2172 _thread_serial_num = Atomic::fetch_then_add(thread_counter, 1); 2173 _start_frame_serial_num = Atomic::fetch_then_add(frame_counter, frame_count()); 2174 } 2175 2176 bool oom_thread() const { 2177 return _oome_constructor != nullptr; 2178 } 2179 2180 int frame_count() const { 2181 return _frames->length() + (oom_thread() ? 1 : 0); 2182 } 2183 2184 u4 thread_serial_num() const { 2185 return (u4)_thread_serial_num; 2186 } 2187 2188 u4 stack_trace_serial_num() const { 2189 return (u4)(_thread_serial_num + STACK_TRACE_ID); 2190 } 2191 2192 // writes HPROF_TRACE and HPROF_FRAME records 2193 // returns number of dumped frames 2194 void dump_stack_traces(AbstractDumpWriter* writer, GrowableArray<Klass*>* klass_map); 2195 2196 // writes HPROF_GC_ROOT_THREAD_OBJ subrecord 2197 void dump_thread_obj(AbstractDumpWriter* writer); 2198 2199 // Walk the stack of the thread. 2200 // Dumps a HPROF_GC_ROOT_JAVA_FRAME subrecord for each local 2201 // Dumps a HPROF_GC_ROOT_JNI_LOCAL subrecord for each JNI local 2202 void dump_stack_refs(AbstractDumpWriter* writer); 2203 2204 }; 2205 2206 ThreadDumper::ThreadDumper(ThreadType thread_type, JavaThread* java_thread, oop thread_oop) 2207 : _thread_type(thread_type), _java_thread(java_thread), _thread_oop(thread_oop), 2208 _oome_constructor(nullptr), 2209 _thread_serial_num(0), _start_frame_serial_num(0) 2210 { 2211 // sanity checks 2212 if (_thread_type == ThreadType::UnmountedVirtual) { 2213 assert(_java_thread == nullptr, "sanity"); 2214 assert(_thread_oop != nullptr, "sanity"); 2215 } else { 2216 assert(_java_thread != nullptr, "sanity"); 2217 assert(_thread_oop != nullptr, "sanity"); 2218 } 2219 2220 _frames = new (mtServiceability) GrowableArray<StackFrameInfo*>(10, mtServiceability); 2221 bool stop_at_vthread_entry = _thread_type == ThreadType::MountedVirtual; 2222 2223 // vframes are resource allocated 2224 Thread* current_thread = Thread::current(); 2225 ResourceMark rm(current_thread); 2226 HandleMark hm(current_thread); 2227 2228 for (vframe* vf = get_top_frame(); vf != nullptr; vf = vf->sender()) { 2229 if (stop_at_vthread_entry && vf->is_vthread_entry()) { 2230 break; 2231 } 2232 if (vf->is_java_frame()) { 2233 javaVFrame* jvf = javaVFrame::cast(vf); 2234 _frames->append(new StackFrameInfo(jvf, false)); 2235 } else { 2236 // ignore non-Java frames 2237 } 2238 } 2239 } 2240 2241 void ThreadDumper::dump_stack_traces(AbstractDumpWriter* writer, GrowableArray<Klass*>* klass_map) { 2242 assert(_thread_serial_num != 0 && _start_frame_serial_num != 0, "serial_nums are not initialized"); 2243 2244 // write HPROF_FRAME records for this thread's stack trace 2245 int depth = _frames->length(); 2246 int frame_serial_num = _start_frame_serial_num; 2247 2248 if (oom_thread()) { 2249 // OOM thread 2250 // write fake frame that makes it look like the thread, which caused OOME, 2251 // is in the OutOfMemoryError zero-parameter constructor 2252 int oome_serial_num = klass_map->find(_oome_constructor->method_holder()); 2253 // the class serial number starts from 1 2254 assert(oome_serial_num > 0, "OutOfMemoryError class not found"); 2255 DumperSupport::dump_stack_frame(writer, ++frame_serial_num, oome_serial_num, _oome_constructor, 0); 2256 depth++; 2257 } 2258 2259 for (int j = 0; j < _frames->length(); j++) { 2260 StackFrameInfo* frame = _frames->at(j); 2261 Method* m = frame->method(); 2262 int class_serial_num = klass_map->find(m->method_holder()); 2263 // the class serial number starts from 1 2264 assert(class_serial_num > 0, "class not found"); 2265 DumperSupport::dump_stack_frame(writer, ++frame_serial_num, class_serial_num, m, frame->bci()); 2266 } 2267 2268 // write HPROF_TRACE record for the thread 2269 DumperSupport::write_header(writer, HPROF_TRACE, checked_cast<u4>(3 * sizeof(u4) + depth * oopSize)); 2270 writer->write_u4(stack_trace_serial_num()); // stack trace serial number 2271 writer->write_u4(thread_serial_num()); // thread serial number 2272 writer->write_u4((u4)depth); // frame count (including oom frame) 2273 for (int j = 1; j <= depth; j++) { 2274 writer->write_id(_start_frame_serial_num + j); 2275 } 2276 } 2277 2278 void ThreadDumper::dump_thread_obj(AbstractDumpWriter * writer) { 2279 assert(_thread_serial_num != 0 && _start_frame_serial_num != 0, "serial_num is not initialized"); 2280 2281 u4 size = 1 + sizeof(address) + 4 + 4; 2282 writer->start_sub_record(HPROF_GC_ROOT_THREAD_OBJ, size); 2283 writer->write_objectID(_thread_oop); 2284 writer->write_u4(thread_serial_num()); // thread serial number 2285 writer->write_u4(stack_trace_serial_num()); // stack trace serial number 2286 writer->end_sub_record(); 2287 } 2288 2289 void ThreadDumper::dump_stack_refs(AbstractDumpWriter * writer) { 2290 assert(_thread_serial_num != 0 && _start_frame_serial_num != 0, "serial_num is not initialized"); 2291 2292 JNILocalsDumper blk(writer, thread_serial_num()); 2293 if (_thread_type == ThreadType::Platform) { 2294 if (!_java_thread->has_last_Java_frame()) { 2295 // no last java frame but there may be JNI locals 2296 _java_thread->active_handles()->oops_do(&blk); 2297 return; 2298 } 2299 } 2300 2301 JavaStackRefDumper java_ref_dumper(writer, thread_serial_num()); 2302 2303 // vframes are resource allocated 2304 Thread* current_thread = Thread::current(); 2305 ResourceMark rm(current_thread); 2306 HandleMark hm(current_thread); 2307 2308 bool stopAtVthreadEntry = _thread_type == ThreadType::MountedVirtual; 2309 frame* last_entry_frame = nullptr; 2310 bool is_top_frame = true; 2311 int depth = 0; 2312 if (oom_thread()) { 2313 depth++; 2314 } 2315 2316 for (vframe* vf = get_top_frame(); vf != nullptr; vf = vf->sender()) { 2317 if (stopAtVthreadEntry && vf->is_vthread_entry()) { 2318 break; 2319 } 2320 2321 if (vf->is_java_frame()) { 2322 javaVFrame* jvf = javaVFrame::cast(vf); 2323 if (!(jvf->method()->is_native())) { 2324 java_ref_dumper.set_frame_number(depth); 2325 java_ref_dumper.dump_java_stack_refs(jvf->locals()); 2326 java_ref_dumper.dump_java_stack_refs(jvf->expressions()); 2327 } else { 2328 // native frame 2329 blk.set_frame_number(depth); 2330 if (is_top_frame) { 2331 // JNI locals for the top frame. 2332 assert(_java_thread != nullptr, "impossible for unmounted vthread"); 2333 _java_thread->active_handles()->oops_do(&blk); 2334 } else { 2335 if (last_entry_frame != nullptr) { 2336 // JNI locals for the entry frame 2337 assert(last_entry_frame->is_entry_frame(), "checking"); 2338 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk); 2339 } 2340 } 2341 } 2342 last_entry_frame = nullptr; 2343 // increment only for Java frames 2344 depth++; 2345 } else { 2346 // externalVFrame - for an entry frame then we report the JNI locals 2347 // when we find the corresponding javaVFrame 2348 frame* fr = vf->frame_pointer(); 2349 assert(fr != nullptr, "sanity check"); 2350 if (fr->is_entry_frame()) { 2351 last_entry_frame = fr; 2352 } 2353 } 2354 is_top_frame = false; 2355 } 2356 assert(depth == frame_count(), "total number of Java frames not matched"); 2357 } 2358 2359 vframe* ThreadDumper::get_top_frame() const { 2360 if (_thread_type == ThreadType::UnmountedVirtual) { 2361 ContinuationWrapper cont(java_lang_VirtualThread::continuation(_thread_oop)); 2362 if (cont.is_empty()) { 2363 return nullptr; 2364 } 2365 assert(!cont.is_mounted(), "sanity check"); 2366 stackChunkOop chunk = cont.last_nonempty_chunk(); 2367 if (chunk == nullptr || chunk->is_empty()) { 2368 return nullptr; 2369 } 2370 2371 RegisterMap reg_map(cont.continuation(), RegisterMap::UpdateMap::include); 2372 frame fr = chunk->top_frame(®_map); 2373 vframe* vf = vframe::new_vframe(&fr, ®_map, nullptr); // don't need JavaThread 2374 return vf; 2375 } 2376 2377 RegisterMap reg_map(_java_thread, 2378 RegisterMap::UpdateMap::include, 2379 RegisterMap::ProcessFrames::include, 2380 RegisterMap::WalkContinuation::skip); 2381 switch (_thread_type) { 2382 case ThreadType::Platform: 2383 if (!_java_thread->has_last_Java_frame()) { 2384 return nullptr; 2385 } 2386 return _java_thread->is_vthread_mounted() 2387 ? _java_thread->carrier_last_java_vframe(®_map) 2388 : _java_thread->platform_thread_last_java_vframe(®_map); 2389 2390 case ThreadType::MountedVirtual: 2391 return _java_thread->last_java_vframe(®_map); 2392 2393 default: // make compilers happy 2394 break; 2395 } 2396 ShouldNotReachHere(); 2397 return nullptr; 2398 } 2399 2400 // Callback to dump thread-related data for unmounted virtual threads; 2401 // implemented by VM_HeapDumper. 2402 class UnmountedVThreadDumper { 2403 public: 2404 virtual void dump_vthread(oop vt, AbstractDumpWriter* segment_writer) = 0; 2405 }; 2406 2407 // Support class used when iterating over the heap. 2408 class HeapObjectDumper : public ObjectClosure { 2409 private: 2410 AbstractDumpWriter* _writer; 2411 AbstractDumpWriter* writer() { return _writer; } 2412 UnmountedVThreadDumper* _vthread_dumper; 2413 2414 DumperClassCacheTable _class_cache; 2415 2416 public: 2417 HeapObjectDumper(AbstractDumpWriter* writer, UnmountedVThreadDumper* vthread_dumper) 2418 : _writer(writer), _vthread_dumper(vthread_dumper) {} 2419 2420 // called for each object in the heap 2421 void do_object(oop o); 2422 }; 2423 2424 void HeapObjectDumper::do_object(oop o) { 2425 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records 2426 if (o->klass() == vmClasses::Class_klass()) { 2427 if (!java_lang_Class::is_primitive(o)) { 2428 return; 2429 } 2430 } 2431 2432 if (DumperSupport::mask_dormant_archived_object(o, nullptr) == nullptr) { 2433 return; 2434 } 2435 2436 if (o->is_instance()) { 2437 // create a HPROF_GC_INSTANCE record for each object 2438 DumperSupport::dump_instance(writer(), o, &_class_cache); 2439 // If we encounter an unmounted virtual thread it needs to be dumped explicitly 2440 // (mounted virtual threads are dumped with their carriers). 2441 if (java_lang_VirtualThread::is_instance(o) 2442 && ThreadDumper::should_dump_vthread(o) && !ThreadDumper::is_vthread_mounted(o)) { 2443 _vthread_dumper->dump_vthread(o, writer()); 2444 } 2445 } else if (o->is_objArray()) { 2446 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array 2447 DumperSupport::dump_object_array(writer(), objArrayOop(o)); 2448 } else if (o->is_flatArray()) { 2449 DumperSupport::dump_flat_array(writer(), flatArrayOop(o), &_class_cache); 2450 } else if (o->is_typeArray()) { 2451 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array 2452 DumperSupport::dump_prim_array(writer(), typeArrayOop(o)); 2453 } 2454 } 2455 2456 // The dumper controller for parallel heap dump 2457 class DumperController : public CHeapObj<mtInternal> { 2458 private: 2459 Monitor* _lock; 2460 Mutex* _global_writer_lock; 2461 2462 const uint _dumper_number; 2463 uint _complete_number; 2464 2465 bool _started; // VM dumper started and acquired global writer lock 2466 2467 public: 2468 DumperController(uint number) : 2469 // _lock and _global_writer_lock are used for synchronization between GC worker threads inside safepoint, 2470 // so we lock with _no_safepoint_check_flag. 2471 // signal_start() acquires _lock when global writer is locked, 2472 // its rank must be less than _global_writer_lock rank. 2473 _lock(new (std::nothrow) PaddedMonitor(Mutex::nosafepoint - 1, "DumperController_lock")), 2474 _global_writer_lock(new (std::nothrow) Mutex(Mutex::nosafepoint, "DumpWriter_lock")), 2475 _dumper_number(number), 2476 _complete_number(0), 2477 _started(false) 2478 {} 2479 2480 ~DumperController() { 2481 delete _lock; 2482 delete _global_writer_lock; 2483 } 2484 2485 // parallel (non VM) dumpers must wait until VM dumper acquires global writer lock 2486 void wait_for_start_signal() { 2487 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag); 2488 while (_started == false) { 2489 ml.wait(); 2490 } 2491 } 2492 2493 void signal_start() { 2494 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag); 2495 _started = true; 2496 ml.notify_all(); 2497 } 2498 2499 void lock_global_writer() { 2500 _global_writer_lock->lock_without_safepoint_check(); 2501 } 2502 2503 void unlock_global_writer() { 2504 _global_writer_lock->unlock(); 2505 } 2506 2507 void dumper_complete(DumpWriter* local_writer, DumpWriter* global_writer) { 2508 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag); 2509 _complete_number++; 2510 // propagate local error to global if any 2511 if (local_writer->has_error()) { 2512 global_writer->set_error(local_writer->error()); 2513 } 2514 ml.notify(); 2515 } 2516 2517 void wait_all_dumpers_complete() { 2518 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag); 2519 while (_complete_number != _dumper_number) { 2520 ml.wait(); 2521 } 2522 } 2523 }; 2524 2525 // DumpMerger merges separate dump files into a complete one 2526 class DumpMerger : public StackObj { 2527 private: 2528 DumpWriter* _writer; 2529 InlinedObjects* _inlined_objects; 2530 const char* _path; 2531 bool _has_error; 2532 int _dump_seq; 2533 2534 private: 2535 void merge_file(const char* path); 2536 void merge_done(); 2537 void set_error(const char* msg); 2538 2539 public: 2540 DumpMerger(const char* path, DumpWriter* writer, InlinedObjects* inlined_objects, int dump_seq) : 2541 _writer(writer), 2542 _inlined_objects(inlined_objects), 2543 _path(path), 2544 _has_error(_writer->has_error()), 2545 _dump_seq(dump_seq) {} 2546 2547 void do_merge(); 2548 2549 // returns path for the parallel DumpWriter (resource allocated) 2550 static char* get_writer_path(const char* base_path, int seq); 2551 2552 }; 2553 2554 char* DumpMerger::get_writer_path(const char* base_path, int seq) { 2555 // approximate required buffer size 2556 size_t buf_size = strlen(base_path) 2557 + 2 // ".p" 2558 + 10 // number (that's enough for 2^32 parallel dumpers) 2559 + 1; // '\0' 2560 2561 char* path = NEW_RESOURCE_ARRAY(char, buf_size); 2562 memset(path, 0, buf_size); 2563 2564 os::snprintf(path, buf_size, "%s.p%d", base_path, seq); 2565 2566 return path; 2567 } 2568 2569 2570 void DumpMerger::merge_done() { 2571 // Writes the HPROF_HEAP_DUMP_END record. 2572 if (!_has_error) { 2573 DumperSupport::end_of_dump(_writer); 2574 _inlined_objects->dump_flat_arrays(_writer); 2575 _writer->flush(); 2576 _inlined_objects->release(); 2577 } 2578 _dump_seq = 0; //reset 2579 } 2580 2581 void DumpMerger::set_error(const char* msg) { 2582 assert(msg != nullptr, "sanity check"); 2583 log_error(heapdump)("%s (file: %s)", msg, _path); 2584 _writer->set_error(msg); 2585 _has_error = true; 2586 } 2587 2588 #ifdef LINUX 2589 // Merge segmented heap files via sendfile, it's more efficient than the 2590 // read+write combination, which would require transferring data to and from 2591 // user space. 2592 void DumpMerger::merge_file(const char* path) { 2593 TraceTime timer("Merge segmented heap file directly", TRACETIME_LOG(Info, heapdump)); 2594 2595 int segment_fd = os::open(path, O_RDONLY, 0); 2596 if (segment_fd == -1) { 2597 set_error("Can not open segmented heap file during merging"); 2598 return; 2599 } 2600 2601 struct stat st; 2602 if (os::stat(path, &st) != 0) { 2603 ::close(segment_fd); 2604 set_error("Can not get segmented heap file size during merging"); 2605 return; 2606 } 2607 2608 // A successful call to sendfile may write fewer bytes than requested; the 2609 // caller should be prepared to retry the call if there were unsent bytes. 2610 jlong offset = 0; 2611 while (offset < st.st_size) { 2612 int ret = os::Linux::sendfile(_writer->get_fd(), segment_fd, &offset, st.st_size); 2613 if (ret == -1) { 2614 ::close(segment_fd); 2615 set_error("Failed to merge segmented heap file"); 2616 return; 2617 } 2618 } 2619 2620 // As sendfile variant does not call the write method of the global writer, 2621 // bytes_written is also incorrect for this variant, we need to explicitly 2622 // accumulate bytes_written for the global writer in this case 2623 julong accum = _writer->bytes_written() + st.st_size; 2624 _writer->set_bytes_written(accum); 2625 ::close(segment_fd); 2626 } 2627 #else 2628 // Generic implementation using read+write 2629 void DumpMerger::merge_file(const char* path) { 2630 TraceTime timer("Merge segmented heap file", TRACETIME_LOG(Info, heapdump)); 2631 2632 fileStream segment_fs(path, "rb"); 2633 if (!segment_fs.is_open()) { 2634 set_error("Can not open segmented heap file during merging"); 2635 return; 2636 } 2637 2638 jlong total = 0; 2639 size_t cnt = 0; 2640 2641 // Use _writer buffer for reading. 2642 while ((cnt = segment_fs.read(_writer->buffer(), 1, _writer->buffer_size())) != 0) { 2643 _writer->set_position(cnt); 2644 _writer->flush(); 2645 total += cnt; 2646 } 2647 2648 if (segment_fs.fileSize() != total) { 2649 set_error("Merged heap dump is incomplete"); 2650 } 2651 } 2652 #endif 2653 2654 void DumpMerger::do_merge() { 2655 TraceTime timer("Merge heap files complete", TRACETIME_LOG(Info, heapdump)); 2656 2657 // Since contents in segmented heap file were already zipped, we don't need to zip 2658 // them again during merging. 2659 AbstractCompressor* saved_compressor = _writer->compressor(); 2660 _writer->set_compressor(nullptr); 2661 2662 // Merge the content of the remaining files into base file. Regardless of whether 2663 // the merge process is successful or not, these segmented files will be deleted. 2664 for (int i = 0; i < _dump_seq; i++) { 2665 ResourceMark rm; 2666 const char* path = get_writer_path(_path, i); 2667 if (!_has_error) { 2668 merge_file(path); 2669 } 2670 // Delete selected segmented heap file nevertheless 2671 if (remove(path) != 0) { 2672 log_info(heapdump)("Removal of segment file (%d) failed (%d)", i, errno); 2673 } 2674 } 2675 2676 // restore compressor for further use 2677 _writer->set_compressor(saved_compressor); 2678 merge_done(); 2679 } 2680 2681 // The VM operation that performs the heap dump 2682 class VM_HeapDumper : public VM_GC_Operation, public WorkerTask, public UnmountedVThreadDumper { 2683 private: 2684 static VM_HeapDumper* _global_dumper; 2685 static DumpWriter* _global_writer; 2686 DumpWriter* _local_writer; 2687 JavaThread* _oome_thread; 2688 Method* _oome_constructor; 2689 bool _gc_before_heap_dump; 2690 GrowableArray<Klass*>* _klass_map; 2691 2692 ThreadDumper** _thread_dumpers; // platform, carrier and mounted virtual threads 2693 int _thread_dumpers_count; 2694 volatile int _thread_serial_num; 2695 volatile int _frame_serial_num; 2696 2697 volatile int _dump_seq; 2698 2699 // Inlined object support. 2700 InlinedObjects _inlined_objects; 2701 2702 // parallel heap dump support 2703 uint _num_dumper_threads; 2704 DumperController* _dumper_controller; 2705 ParallelObjectIterator* _poi; 2706 2707 // Dumper id of VMDumper thread. 2708 static const int VMDumperId = 0; 2709 // VM dumper dumps both heap and non-heap data, other dumpers dump heap-only data. 2710 static bool is_vm_dumper(int dumper_id) { return dumper_id == VMDumperId; } 2711 // the 1st dumper calling get_next_dumper_id becomes VM dumper 2712 int get_next_dumper_id() { 2713 return Atomic::fetch_then_add(&_dump_seq, 1); 2714 } 2715 2716 // accessors and setters 2717 static VM_HeapDumper* dumper() { assert(_global_dumper != nullptr, "Error"); return _global_dumper; } 2718 static DumpWriter* writer() { assert(_global_writer != nullptr, "Error"); return _global_writer; } 2719 2720 void set_global_dumper() { 2721 assert(_global_dumper == nullptr, "Error"); 2722 _global_dumper = this; 2723 } 2724 void set_global_writer() { 2725 assert(_global_writer == nullptr, "Error"); 2726 _global_writer = _local_writer; 2727 } 2728 void clear_global_dumper() { _global_dumper = nullptr; } 2729 void clear_global_writer() { _global_writer = nullptr; } 2730 2731 bool skip_operation() const; 2732 2733 // writes a HPROF_LOAD_CLASS record to global writer 2734 static void do_load_class(Klass* k); 2735 2736 // HPROF_GC_ROOT_THREAD_OBJ records for platform and mounted virtual threads 2737 void dump_threads(AbstractDumpWriter* writer); 2738 2739 void add_class_serial_number(Klass* k, int serial_num) { 2740 _klass_map->at_put_grow(serial_num, k); 2741 } 2742 2743 bool is_oom_thread(JavaThread* thread) const { 2744 return thread == _oome_thread && _oome_constructor != nullptr; 2745 } 2746 2747 // HPROF_TRACE and HPROF_FRAME records for platform and mounted virtual threads 2748 void dump_stack_traces(AbstractDumpWriter* writer); 2749 2750 public: 2751 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome, uint num_dump_threads) : 2752 VM_GC_Operation(0 /* total collections, dummy, ignored */, 2753 GCCause::_heap_dump /* GC Cause */, 2754 0 /* total full collections, dummy, ignored */, 2755 gc_before_heap_dump), 2756 WorkerTask("dump heap") { 2757 _local_writer = writer; 2758 _gc_before_heap_dump = gc_before_heap_dump; 2759 _klass_map = new (mtServiceability) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, mtServiceability); 2760 2761 _thread_dumpers = nullptr; 2762 _thread_dumpers_count = 0; 2763 _thread_serial_num = 1; 2764 _frame_serial_num = 1; 2765 2766 _dump_seq = VMDumperId; 2767 _num_dumper_threads = num_dump_threads; 2768 _dumper_controller = nullptr; 2769 _poi = nullptr; 2770 if (oome) { 2771 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread"); 2772 // get OutOfMemoryError zero-parameter constructor 2773 InstanceKlass* oome_ik = vmClasses::OutOfMemoryError_klass(); 2774 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(), 2775 vmSymbols::void_method_signature()); 2776 // get thread throwing OOME when generating the heap dump at OOME 2777 _oome_thread = JavaThread::current(); 2778 } else { 2779 _oome_thread = nullptr; 2780 _oome_constructor = nullptr; 2781 } 2782 } 2783 2784 ~VM_HeapDumper() { 2785 if (_thread_dumpers != nullptr) { 2786 for (int i = 0; i < _thread_dumpers_count; i++) { 2787 delete _thread_dumpers[i]; 2788 } 2789 FREE_C_HEAP_ARRAY(ThreadDumper*, _thread_dumpers); 2790 } 2791 2792 if (_dumper_controller != nullptr) { 2793 delete _dumper_controller; 2794 _dumper_controller = nullptr; 2795 } 2796 delete _klass_map; 2797 } 2798 int dump_seq() { return _dump_seq; } 2799 bool is_parallel_dump() { return _num_dumper_threads > 1; } 2800 void prepare_parallel_dump(WorkerThreads* workers); 2801 2802 InlinedObjects* inlined_objects() { return &_inlined_objects; } 2803 2804 VMOp_Type type() const { return VMOp_HeapDumper; } 2805 virtual bool doit_prologue(); 2806 void doit(); 2807 void work(uint worker_id); 2808 2809 // UnmountedVThreadDumper implementation 2810 void dump_vthread(oop vt, AbstractDumpWriter* segment_writer); 2811 }; 2812 2813 VM_HeapDumper* VM_HeapDumper::_global_dumper = nullptr; 2814 DumpWriter* VM_HeapDumper::_global_writer = nullptr; 2815 2816 bool VM_HeapDumper::skip_operation() const { 2817 return false; 2818 } 2819 2820 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record 2821 void DumperSupport::end_of_dump(AbstractDumpWriter* writer) { 2822 writer->finish_dump_segment(); 2823 2824 writer->write_u1(HPROF_HEAP_DUMP_END); 2825 writer->write_u4(0); 2826 writer->write_u4(0); 2827 } 2828 2829 // writes a HPROF_LOAD_CLASS record for the class 2830 void VM_HeapDumper::do_load_class(Klass* k) { 2831 static u4 class_serial_num = 0; 2832 2833 // len of HPROF_LOAD_CLASS record 2834 u4 remaining = 2*oopSize + 2*sizeof(u4); 2835 2836 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining); 2837 2838 // class serial number is just a number 2839 writer()->write_u4(++class_serial_num); 2840 2841 // class ID 2842 writer()->write_classID(k); 2843 2844 // add the Klass* and class serial number pair 2845 dumper()->add_class_serial_number(k, class_serial_num); 2846 2847 writer()->write_u4(STACK_TRACE_ID); 2848 2849 // class name ID 2850 Symbol* name = k->name(); 2851 writer()->write_symbolID(name); 2852 } 2853 2854 // Write a HPROF_GC_ROOT_THREAD_OBJ record for platform/carrier and mounted virtual threads. 2855 // Then walk the stack so that locals and JNI locals are dumped. 2856 void VM_HeapDumper::dump_threads(AbstractDumpWriter* writer) { 2857 for (int i = 0; i < _thread_dumpers_count; i++) { 2858 _thread_dumpers[i]->dump_thread_obj(writer); 2859 _thread_dumpers[i]->dump_stack_refs(writer); 2860 } 2861 } 2862 2863 bool VM_HeapDumper::doit_prologue() { 2864 if (_gc_before_heap_dump && UseZGC) { 2865 // ZGC cannot perform a synchronous GC cycle from within the VM thread. 2866 // So ZCollectedHeap::collect_as_vm_thread() is a noop. To respect the 2867 // _gc_before_heap_dump flag a synchronous GC cycle is performed from 2868 // the caller thread in the prologue. 2869 Universe::heap()->collect(GCCause::_heap_dump); 2870 } 2871 return VM_GC_Operation::doit_prologue(); 2872 } 2873 2874 void VM_HeapDumper::prepare_parallel_dump(WorkerThreads* workers) { 2875 uint num_active_workers = workers != nullptr ? workers->active_workers() : 0; 2876 uint num_requested_dump_threads = _num_dumper_threads; 2877 // check if we can dump in parallel based on requested and active threads 2878 if (num_active_workers <= 1 || num_requested_dump_threads <= 1) { 2879 _num_dumper_threads = 1; 2880 } else { 2881 _num_dumper_threads = clamp(num_requested_dump_threads, 2U, num_active_workers); 2882 } 2883 _dumper_controller = new (std::nothrow) DumperController(_num_dumper_threads); 2884 bool can_parallel = _num_dumper_threads > 1; 2885 log_info(heapdump)("Requested dump threads %u, active dump threads %u, " 2886 "actual dump threads %u, parallelism %s", 2887 num_requested_dump_threads, num_active_workers, 2888 _num_dumper_threads, can_parallel ? "true" : "false"); 2889 } 2890 2891 // The VM operation that dumps the heap. The dump consists of the following 2892 // records: 2893 // 2894 // HPROF_HEADER 2895 // [HPROF_UTF8]* 2896 // [HPROF_LOAD_CLASS]* 2897 // [[HPROF_FRAME]*|HPROF_TRACE]* 2898 // [HPROF_GC_CLASS_DUMP]* 2899 // [HPROF_HEAP_DUMP_SEGMENT]* 2900 // HPROF_HEAP_DUMP_END 2901 // 2902 // The HPROF_TRACE records represent the stack traces where the heap dump 2903 // is generated and a "dummy trace" record which does not include 2904 // any frames. The dummy trace record is used to be referenced as the 2905 // unknown object alloc site. 2906 // 2907 // Each HPROF_HEAP_DUMP_SEGMENT record has a length followed by sub-records. 2908 // To allow the heap dump be generated in a single pass we remember the position 2909 // of the dump length and fix it up after all sub-records have been written. 2910 // To generate the sub-records we iterate over the heap, writing 2911 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP 2912 // records as we go. Once that is done we write records for some of the GC 2913 // roots. 2914 2915 void VM_HeapDumper::doit() { 2916 2917 CollectedHeap* ch = Universe::heap(); 2918 2919 ch->ensure_parsability(false); // must happen, even if collection does 2920 // not happen (e.g. due to GCLocker) 2921 2922 if (_gc_before_heap_dump) { 2923 if (GCLocker::is_active()) { 2924 warning("GC locker is held; pre-heapdump GC was skipped"); 2925 } else { 2926 ch->collect_as_vm_thread(GCCause::_heap_dump); 2927 } 2928 } 2929 2930 // At this point we should be the only dumper active, so 2931 // the following should be safe. 2932 set_global_dumper(); 2933 set_global_writer(); 2934 2935 WorkerThreads* workers = ch->safepoint_workers(); 2936 prepare_parallel_dump(workers); 2937 2938 if (!is_parallel_dump()) { 2939 work(VMDumperId); 2940 } else { 2941 ParallelObjectIterator poi(_num_dumper_threads); 2942 _poi = &poi; 2943 workers->run_task(this, _num_dumper_threads); 2944 _poi = nullptr; 2945 } 2946 2947 // Now we clear the global variables, so that a future dumper can run. 2948 clear_global_dumper(); 2949 clear_global_writer(); 2950 } 2951 2952 void VM_HeapDumper::work(uint worker_id) { 2953 // VM Dumper works on all non-heap data dumping and part of heap iteration. 2954 int dumper_id = get_next_dumper_id(); 2955 2956 if (is_vm_dumper(dumper_id)) { 2957 // lock global writer, it will be unlocked after VM Dumper finishes with non-heap data 2958 _dumper_controller->lock_global_writer(); 2959 _dumper_controller->signal_start(); 2960 } else { 2961 _dumper_controller->wait_for_start_signal(); 2962 } 2963 2964 if (is_vm_dumper(dumper_id)) { 2965 TraceTime timer("Dump non-objects", TRACETIME_LOG(Info, heapdump)); 2966 // Write the file header - we always use 1.0.2 2967 const char* header = "JAVA PROFILE 1.0.2"; 2968 2969 // header is few bytes long - no chance to overflow int 2970 writer()->write_raw(header, strlen(header) + 1); // NUL terminated 2971 writer()->write_u4(oopSize); 2972 // timestamp is current time in ms 2973 writer()->write_u8(os::javaTimeMillis()); 2974 // HPROF_UTF8 records 2975 SymbolTableDumper sym_dumper(writer()); 2976 SymbolTable::symbols_do(&sym_dumper); 2977 2978 // HPROF_UTF8 records for inlined field names. 2979 inlined_objects()->init(); 2980 inlined_objects()->dump_inlined_field_names(writer()); 2981 2982 // HPROF_INLINED_FIELDS 2983 inlined_objects()->dump_classed_with_inlined_fields(writer()); 2984 2985 // write HPROF_LOAD_CLASS records 2986 { 2987 LockedClassesDo locked_load_classes(&do_load_class); 2988 ClassLoaderDataGraph::classes_do(&locked_load_classes); 2989 } 2990 2991 // write HPROF_FRAME and HPROF_TRACE records 2992 // this must be called after _klass_map is built when iterating the classes above. 2993 dump_stack_traces(writer()); 2994 2995 // unlock global writer, so parallel dumpers can dump stack traces of unmounted virtual threads 2996 _dumper_controller->unlock_global_writer(); 2997 } 2998 2999 // HPROF_HEAP_DUMP/HPROF_HEAP_DUMP_SEGMENT starts here 3000 3001 ResourceMark rm; 3002 // share global compressor, local DumpWriter is not responsible for its life cycle 3003 DumpWriter segment_writer(DumpMerger::get_writer_path(writer()->get_file_path(), dumper_id), 3004 writer()->is_overwrite(), writer()->compressor()); 3005 if (!segment_writer.has_error()) { 3006 if (is_vm_dumper(dumper_id)) { 3007 // dump some non-heap subrecords to heap dump segment 3008 TraceTime timer("Dump non-objects (part 2)", TRACETIME_LOG(Info, heapdump)); 3009 // Writes HPROF_GC_CLASS_DUMP records 3010 ClassDumper class_dumper(&segment_writer); 3011 ClassLoaderDataGraph::classes_do(&class_dumper); 3012 3013 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals 3014 dump_threads(&segment_writer); 3015 3016 // HPROF_GC_ROOT_JNI_GLOBAL 3017 JNIGlobalsDumper jni_dumper(&segment_writer); 3018 JNIHandles::oops_do(&jni_dumper); 3019 // technically not jni roots, but global roots 3020 // for things like preallocated throwable backtraces 3021 Universe::vm_global()->oops_do(&jni_dumper); 3022 // HPROF_GC_ROOT_STICKY_CLASS 3023 // These should be classes in the null class loader data, and not all classes 3024 // if !ClassUnloading 3025 StickyClassDumper stiky_class_dumper(&segment_writer); 3026 ClassLoaderData::the_null_class_loader_data()->classes_do(&stiky_class_dumper); 3027 } 3028 3029 // Heap iteration. 3030 // writes HPROF_GC_INSTANCE_DUMP records. 3031 // After each sub-record is written check_segment_length will be invoked 3032 // to check if the current segment exceeds a threshold. If so, a new 3033 // segment is started. 3034 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk 3035 // of the heap dump. 3036 3037 TraceTime timer(is_parallel_dump() ? "Dump heap objects in parallel" : "Dump heap objects", TRACETIME_LOG(Info, heapdump)); 3038 HeapObjectDumper obj_dumper(&segment_writer, this); 3039 if (!is_parallel_dump()) { 3040 Universe::heap()->object_iterate(&obj_dumper); 3041 } else { 3042 // == Parallel dump 3043 _poi->object_iterate(&obj_dumper, worker_id); 3044 } 3045 3046 segment_writer.finish_dump_segment(); 3047 segment_writer.flush(); 3048 } 3049 3050 _dumper_controller->dumper_complete(&segment_writer, writer()); 3051 3052 if (is_vm_dumper(dumper_id)) { 3053 _dumper_controller->wait_all_dumpers_complete(); 3054 3055 // flush global writer 3056 writer()->flush(); 3057 3058 // At this point, all fragments of the heapdump have been written to separate files. 3059 // We need to merge them into a complete heapdump and write HPROF_HEAP_DUMP_END at that time. 3060 } 3061 } 3062 3063 void VM_HeapDumper::dump_stack_traces(AbstractDumpWriter* writer) { 3064 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites 3065 DumperSupport::write_header(writer, HPROF_TRACE, 3 * sizeof(u4)); 3066 writer->write_u4((u4)STACK_TRACE_ID); 3067 writer->write_u4(0); // thread number 3068 writer->write_u4(0); // frame count 3069 3070 // max number if every platform thread is carrier with mounted virtual thread 3071 _thread_dumpers = NEW_C_HEAP_ARRAY(ThreadDumper*, Threads::number_of_threads() * 2, mtInternal); 3072 3073 for (JavaThreadIteratorWithHandle jtiwh; JavaThread * thread = jtiwh.next(); ) { 3074 if (ThreadDumper::should_dump_pthread(thread)) { 3075 bool add_oom_frame = is_oom_thread(thread); 3076 3077 oop mounted_vt = thread->is_vthread_mounted() ? thread->vthread() : nullptr; 3078 if (mounted_vt != nullptr && !ThreadDumper::should_dump_vthread(mounted_vt)) { 3079 mounted_vt = nullptr; 3080 } 3081 3082 // mounted vthread (if any) 3083 if (mounted_vt != nullptr) { 3084 ThreadDumper* thread_dumper = new ThreadDumper(ThreadDumper::ThreadType::MountedVirtual, thread, mounted_vt); 3085 _thread_dumpers[_thread_dumpers_count++] = thread_dumper; 3086 if (add_oom_frame) { 3087 thread_dumper->add_oom_frame(_oome_constructor); 3088 // we add oom frame to the VT stack, don't add it to the carrier thread stack 3089 add_oom_frame = false; 3090 } 3091 thread_dumper->init_serial_nums(&_thread_serial_num, &_frame_serial_num); 3092 thread_dumper->dump_stack_traces(writer, _klass_map); 3093 } 3094 3095 // platform or carrier thread 3096 ThreadDumper* thread_dumper = new ThreadDumper(ThreadDumper::ThreadType::Platform, thread, thread->threadObj()); 3097 _thread_dumpers[_thread_dumpers_count++] = thread_dumper; 3098 if (add_oom_frame) { 3099 thread_dumper->add_oom_frame(_oome_constructor); 3100 } 3101 thread_dumper->init_serial_nums(&_thread_serial_num, &_frame_serial_num); 3102 thread_dumper->dump_stack_traces(writer, _klass_map); 3103 } 3104 } 3105 } 3106 3107 void VM_HeapDumper::dump_vthread(oop vt, AbstractDumpWriter* segment_writer) { 3108 // unmounted vthread has no JavaThread 3109 ThreadDumper thread_dumper(ThreadDumper::ThreadType::UnmountedVirtual, nullptr, vt); 3110 thread_dumper.init_serial_nums(&_thread_serial_num, &_frame_serial_num); 3111 3112 // write HPROF_TRACE/HPROF_FRAME records to global writer 3113 _dumper_controller->lock_global_writer(); 3114 thread_dumper.dump_stack_traces(writer(), _klass_map); 3115 _dumper_controller->unlock_global_writer(); 3116 3117 // write HPROF_GC_ROOT_THREAD_OBJ/HPROF_GC_ROOT_JAVA_FRAME/HPROF_GC_ROOT_JNI_LOCAL subrecord 3118 // to segment writer 3119 thread_dumper.dump_thread_obj(segment_writer); 3120 thread_dumper.dump_stack_refs(segment_writer); 3121 } 3122 3123 // dump the heap to given path. 3124 int HeapDumper::dump(const char* path, outputStream* out, int compression, bool overwrite, uint num_dump_threads) { 3125 assert(path != nullptr && strlen(path) > 0, "path missing"); 3126 3127 // print message in interactive case 3128 if (out != nullptr) { 3129 out->print_cr("Dumping heap to %s ...", path); 3130 timer()->start(); 3131 } 3132 3133 if (_oome && num_dump_threads > 1) { 3134 // Each additional parallel writer requires several MB of internal memory 3135 // (DumpWriter buffer, DumperClassCacheTable, GZipCompressor buffers). 3136 // For the OOM handling we may already be limited in memory. 3137 // Lets ensure we have at least 20MB per thread. 3138 julong max_threads = os::free_memory() / (20 * M); 3139 if (num_dump_threads > max_threads) { 3140 num_dump_threads = MAX2<uint>(1, (uint)max_threads); 3141 } 3142 } 3143 3144 // create JFR event 3145 EventHeapDump event; 3146 3147 AbstractCompressor* compressor = nullptr; 3148 3149 if (compression > 0) { 3150 compressor = new (std::nothrow) GZipCompressor(compression); 3151 3152 if (compressor == nullptr) { 3153 set_error("Could not allocate gzip compressor"); 3154 return -1; 3155 } 3156 } 3157 3158 DumpWriter writer(path, overwrite, compressor); 3159 3160 if (writer.error() != nullptr) { 3161 set_error(writer.error()); 3162 if (out != nullptr) { 3163 out->print_cr("Unable to create %s: %s", path, 3164 (error() != nullptr) ? error() : "reason unknown"); 3165 } 3166 return -1; 3167 } 3168 3169 // generate the segmented heap dump into separate files 3170 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome, num_dump_threads); 3171 VMThread::execute(&dumper); 3172 3173 // record any error that the writer may have encountered 3174 set_error(writer.error()); 3175 3176 // Heap dump process is done in two phases 3177 // 3178 // Phase 1: Concurrent threads directly write heap data to multiple heap files. 3179 // This is done by VM_HeapDumper, which is performed within safepoint. 3180 // 3181 // Phase 2: Merge multiple heap files into one complete heap dump file. 3182 // This is done by DumpMerger, which is performed outside safepoint 3183 3184 DumpMerger merger(path, &writer, dumper.inlined_objects(), dumper.dump_seq()); 3185 // Perform heapdump file merge operation in the current thread prevents us 3186 // from occupying the VM Thread, which in turn affects the occurrence of 3187 // GC and other VM operations. 3188 merger.do_merge(); 3189 if (writer.error() != nullptr) { 3190 set_error(writer.error()); 3191 } 3192 3193 // emit JFR event 3194 if (error() == nullptr) { 3195 event.set_destination(path); 3196 event.set_gcBeforeDump(_gc_before_heap_dump); 3197 event.set_size(writer.bytes_written()); 3198 event.set_onOutOfMemoryError(_oome); 3199 event.set_overwrite(overwrite); 3200 event.set_compression(compression); 3201 event.commit(); 3202 } else { 3203 log_debug(cds, heap)("Error %s while dumping heap", error()); 3204 } 3205 3206 // print message in interactive case 3207 if (out != nullptr) { 3208 timer()->stop(); 3209 if (error() == nullptr) { 3210 out->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]", 3211 writer.bytes_written(), timer()->seconds()); 3212 } else { 3213 out->print_cr("Dump file is incomplete: %s", writer.error()); 3214 } 3215 } 3216 3217 if (compressor != nullptr) { 3218 delete compressor; 3219 } 3220 return (writer.error() == nullptr) ? 0 : -1; 3221 } 3222 3223 // stop timer (if still active), and free any error string we might be holding 3224 HeapDumper::~HeapDumper() { 3225 if (timer()->is_active()) { 3226 timer()->stop(); 3227 } 3228 set_error(nullptr); 3229 } 3230 3231 3232 // returns the error string (resource allocated), or null 3233 char* HeapDumper::error_as_C_string() const { 3234 if (error() != nullptr) { 3235 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1); 3236 strcpy(str, error()); 3237 return str; 3238 } else { 3239 return nullptr; 3240 } 3241 } 3242 3243 // set the error string 3244 void HeapDumper::set_error(char const* error) { 3245 if (_error != nullptr) { 3246 os::free(_error); 3247 } 3248 if (error == nullptr) { 3249 _error = nullptr; 3250 } else { 3251 _error = os::strdup(error); 3252 assert(_error != nullptr, "allocation failure"); 3253 } 3254 } 3255 3256 // Called by out-of-memory error reporting by a single Java thread 3257 // outside of a JVM safepoint 3258 void HeapDumper::dump_heap_from_oome() { 3259 HeapDumper::dump_heap(true); 3260 } 3261 3262 // Called by error reporting by a single Java thread outside of a JVM safepoint, 3263 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various 3264 // callers are strictly serialized and guaranteed not to interfere below. For more 3265 // general use, however, this method will need modification to prevent 3266 // inteference when updating the static variables base_path and dump_file_seq below. 3267 void HeapDumper::dump_heap() { 3268 HeapDumper::dump_heap(false); 3269 } 3270 3271 void HeapDumper::dump_heap(bool oome) { 3272 static char base_path[JVM_MAXPATHLEN] = {'\0'}; 3273 static uint dump_file_seq = 0; 3274 char* my_path; 3275 const int max_digit_chars = 20; 3276 3277 const char* dump_file_name = "java_pid"; 3278 const char* dump_file_ext = HeapDumpGzipLevel > 0 ? ".hprof.gz" : ".hprof"; 3279 3280 // The dump file defaults to java_pid<pid>.hprof in the current working 3281 // directory. HeapDumpPath=<file> can be used to specify an alternative 3282 // dump file name or a directory where dump file is created. 3283 if (dump_file_seq == 0) { // first time in, we initialize base_path 3284 // Calculate potentially longest base path and check if we have enough 3285 // allocated statically. 3286 const size_t total_length = 3287 (HeapDumpPath == nullptr ? 0 : strlen(HeapDumpPath)) + 3288 strlen(os::file_separator()) + max_digit_chars + 3289 strlen(dump_file_name) + strlen(dump_file_ext) + 1; 3290 if (total_length > sizeof(base_path)) { 3291 warning("Cannot create heap dump file. HeapDumpPath is too long."); 3292 return; 3293 } 3294 3295 bool use_default_filename = true; 3296 if (HeapDumpPath == nullptr || HeapDumpPath[0] == '\0') { 3297 // HeapDumpPath=<file> not specified 3298 } else { 3299 strcpy(base_path, HeapDumpPath); 3300 // check if the path is a directory (must exist) 3301 DIR* dir = os::opendir(base_path); 3302 if (dir == nullptr) { 3303 use_default_filename = false; 3304 } else { 3305 // HeapDumpPath specified a directory. We append a file separator 3306 // (if needed). 3307 os::closedir(dir); 3308 size_t fs_len = strlen(os::file_separator()); 3309 if (strlen(base_path) >= fs_len) { 3310 char* end = base_path; 3311 end += (strlen(base_path) - fs_len); 3312 if (strcmp(end, os::file_separator()) != 0) { 3313 strcat(base_path, os::file_separator()); 3314 } 3315 } 3316 } 3317 } 3318 // If HeapDumpPath wasn't a file name then we append the default name 3319 if (use_default_filename) { 3320 const size_t dlen = strlen(base_path); // if heap dump dir specified 3321 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s", 3322 dump_file_name, os::current_process_id(), dump_file_ext); 3323 } 3324 const size_t len = strlen(base_path) + 1; 3325 my_path = (char*)os::malloc(len, mtInternal); 3326 if (my_path == nullptr) { 3327 warning("Cannot create heap dump file. Out of system memory."); 3328 return; 3329 } 3330 strncpy(my_path, base_path, len); 3331 } else { 3332 // Append a sequence number id for dumps following the first 3333 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0 3334 my_path = (char*)os::malloc(len, mtInternal); 3335 if (my_path == nullptr) { 3336 warning("Cannot create heap dump file. Out of system memory."); 3337 return; 3338 } 3339 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq); 3340 } 3341 dump_file_seq++; // increment seq number for next time we dump 3342 3343 HeapDumper dumper(false /* no GC before heap dump */, 3344 oome /* pass along out-of-memory-error flag */); 3345 dumper.dump(my_path, tty, HeapDumpGzipLevel); 3346 os::free(my_path); 3347 }