1 /* 2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "jvm.h" 27 #include "classfile/classLoaderData.inline.hpp" 28 #include "classfile/classLoaderDataGraph.hpp" 29 #include "classfile/symbolTable.hpp" 30 #include "classfile/systemDictionary.hpp" 31 #include "classfile/vmSymbols.hpp" 32 #include "gc/shared/gcLocker.hpp" 33 #include "gc/shared/vmGCOperations.hpp" 34 #include "memory/allocation.inline.hpp" 35 #include "memory/resourceArea.hpp" 36 #include "memory/universe.hpp" 37 #include "oops/objArrayKlass.hpp" 38 #include "oops/objArrayOop.inline.hpp" 39 #include "oops/oop.inline.hpp" 40 #include "oops/typeArrayOop.inline.hpp" 41 #include "runtime/frame.inline.hpp" 42 #include "runtime/handles.inline.hpp" 43 #include "runtime/javaCalls.hpp" 44 #include "runtime/jniHandles.hpp" 45 #include "runtime/os.inline.hpp" 46 #include "runtime/reflectionUtils.hpp" 47 #include "runtime/thread.inline.hpp" 48 #include "runtime/threadSMR.hpp" 49 #include "runtime/vframe.hpp" 50 #include "runtime/vmThread.hpp" 51 #include "runtime/vm_operations.hpp" 52 #include "services/heapDumper.hpp" 53 #include "services/threadService.hpp" 54 #include "utilities/macros.hpp" 55 #include "utilities/ostream.hpp" 56 57 /* 58 * HPROF binary format - description copied from: 59 * src/share/demo/jvmti/hprof/hprof_io.c 60 * 61 * 62 * header "JAVA PROFILE 1.0.2" (0-terminated) 63 * 64 * u4 size of identifiers. Identifiers are used to represent 65 * UTF8 strings, objects, stack traces, etc. They usually 66 * have the same size as host pointers. For example, on 67 * Solaris and Win32, the size is 4. 68 * u4 high word 69 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70 70 * [record]* a sequence of records. 71 * 72 * 73 * Record format: 74 * 75 * u1 a TAG denoting the type of the record 76 * u4 number of *microseconds* since the time stamp in the 77 * header. (wraps around in a little more than an hour) 78 * u4 number of bytes *remaining* in the record. Note that 79 * this number excludes the tag and the length field itself. 80 * [u1]* BODY of the record (a sequence of bytes) 81 * 82 * 83 * The following TAGs are supported: 84 * 85 * TAG BODY notes 86 *---------------------------------------------------------- 87 * HPROF_UTF8 a UTF8-encoded name 88 * 89 * id name ID 90 * [u1]* UTF8 characters (no trailing zero) 91 * 92 * HPROF_LOAD_CLASS a newly loaded class 93 * 94 * u4 class serial number (> 0) 95 * id class object ID 96 * u4 stack trace serial number 97 * id class name ID 98 * 99 * HPROF_UNLOAD_CLASS an unloading class 100 * 101 * u4 class serial_number 102 * 103 * HPROF_FRAME a Java stack frame 104 * 105 * id stack frame ID 106 * id method name ID 107 * id method signature ID 108 * id source file name ID 109 * u4 class serial number 110 * i4 line number. >0: normal 111 * -1: unknown 112 * -2: compiled method 113 * -3: native method 114 * 115 * HPROF_TRACE a Java stack trace 116 * 117 * u4 stack trace serial number 118 * u4 thread serial number 119 * u4 number of frames 120 * [id]* stack frame IDs 121 * 122 * 123 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC 124 * 125 * u2 flags 0x0001: incremental vs. complete 126 * 0x0002: sorted by allocation vs. live 127 * 0x0004: whether to force a GC 128 * u4 cutoff ratio 129 * u4 total live bytes 130 * u4 total live instances 131 * u8 total bytes allocated 132 * u8 total instances allocated 133 * u4 number of sites that follow 134 * [u1 is_array: 0: normal object 135 * 2: object array 136 * 4: boolean array 137 * 5: char array 138 * 6: float array 139 * 7: double array 140 * 8: byte array 141 * 9: short array 142 * 10: int array 143 * 11: long array 144 * u4 class serial number (may be zero during startup) 145 * u4 stack trace serial number 146 * u4 number of bytes alive 147 * u4 number of instances alive 148 * u4 number of bytes allocated 149 * u4]* number of instance allocated 150 * 151 * HPROF_START_THREAD a newly started thread. 152 * 153 * u4 thread serial number (> 0) 154 * id thread object ID 155 * u4 stack trace serial number 156 * id thread name ID 157 * id thread group name ID 158 * id thread group parent name ID 159 * 160 * HPROF_END_THREAD a terminating thread. 161 * 162 * u4 thread serial number 163 * 164 * HPROF_HEAP_SUMMARY heap summary 165 * 166 * u4 total live bytes 167 * u4 total live instances 168 * u8 total bytes allocated 169 * u8 total instances allocated 170 * 171 * HPROF_HEAP_DUMP denote a heap dump 172 * 173 * [heap dump sub-records]* 174 * 175 * There are four kinds of heap dump sub-records: 176 * 177 * u1 sub-record type 178 * 179 * HPROF_GC_ROOT_UNKNOWN unknown root 180 * 181 * id object ID 182 * 183 * HPROF_GC_ROOT_THREAD_OBJ thread object 184 * 185 * id thread object ID (may be 0 for a 186 * thread newly attached through JNI) 187 * u4 thread sequence number 188 * u4 stack trace sequence number 189 * 190 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root 191 * 192 * id object ID 193 * id JNI global ref ID 194 * 195 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref 196 * 197 * id object ID 198 * u4 thread serial number 199 * u4 frame # in stack trace (-1 for empty) 200 * 201 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame 202 * 203 * id object ID 204 * u4 thread serial number 205 * u4 frame # in stack trace (-1 for empty) 206 * 207 * HPROF_GC_ROOT_NATIVE_STACK Native stack 208 * 209 * id object ID 210 * u4 thread serial number 211 * 212 * HPROF_GC_ROOT_STICKY_CLASS System class 213 * 214 * id object ID 215 * 216 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block 217 * 218 * id object ID 219 * u4 thread serial number 220 * 221 * HPROF_GC_ROOT_MONITOR_USED Busy monitor 222 * 223 * id object ID 224 * 225 * HPROF_GC_CLASS_DUMP dump of a class object 226 * 227 * id class object ID 228 * u4 stack trace serial number 229 * id super class object ID 230 * id class loader object ID 231 * id signers object ID 232 * id protection domain object ID 233 * id reserved 234 * id reserved 235 * 236 * u4 instance size (in bytes) 237 * 238 * u2 size of constant pool 239 * [u2, constant pool index, 240 * ty, type 241 * 2: object 242 * 4: boolean 243 * 5: char 244 * 6: float 245 * 7: double 246 * 8: byte 247 * 9: short 248 * 10: int 249 * 11: long 250 * vl]* and value 251 * 252 * u2 number of static fields 253 * [id, static field name, 254 * ty, type, 255 * vl]* and value 256 * 257 * u2 number of inst. fields (not inc. super) 258 * [id, instance field name, 259 * ty]* type 260 * 261 * HPROF_GC_INSTANCE_DUMP dump of a normal object 262 * 263 * id object ID 264 * u4 stack trace serial number 265 * id class object ID 266 * u4 number of bytes that follow 267 * [vl]* instance field values (class, followed 268 * by super, super's super ...) 269 * 270 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array 271 * 272 * id array object ID 273 * u4 stack trace serial number 274 * u4 number of elements 275 * id array class ID 276 * [id]* elements 277 * 278 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array 279 * 280 * id array object ID 281 * u4 stack trace serial number 282 * u4 number of elements 283 * u1 element type 284 * 4: boolean array 285 * 5: char array 286 * 6: float array 287 * 7: double array 288 * 8: byte array 289 * 9: short array 290 * 10: int array 291 * 11: long array 292 * [u1]* elements 293 * 294 * HPROF_CPU_SAMPLES a set of sample traces of running threads 295 * 296 * u4 total number of samples 297 * u4 # of traces 298 * [u4 # of samples 299 * u4]* stack trace serial number 300 * 301 * HPROF_CONTROL_SETTINGS the settings of on/off switches 302 * 303 * u4 0x00000001: alloc traces on/off 304 * 0x00000002: cpu sampling on/off 305 * u2 stack trace depth 306 * 307 * 308 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally 309 * be generated as a sequence of heap dump segments. This sequence is 310 * terminated by an end record. The additional tags allowed by format 311 * "JAVA PROFILE 1.0.2" are: 312 * 313 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment 314 * 315 * [heap dump sub-records]* 316 * The same sub-record types allowed by HPROF_HEAP_DUMP 317 * 318 * HPROF_HEAP_DUMP_END denotes the end of a heap dump 319 * 320 */ 321 322 323 // HPROF tags 324 325 typedef enum { 326 // top-level records 327 HPROF_UTF8 = 0x01, 328 HPROF_LOAD_CLASS = 0x02, 329 HPROF_UNLOAD_CLASS = 0x03, 330 HPROF_FRAME = 0x04, 331 HPROF_TRACE = 0x05, 332 HPROF_ALLOC_SITES = 0x06, 333 HPROF_HEAP_SUMMARY = 0x07, 334 HPROF_START_THREAD = 0x0A, 335 HPROF_END_THREAD = 0x0B, 336 HPROF_HEAP_DUMP = 0x0C, 337 HPROF_CPU_SAMPLES = 0x0D, 338 HPROF_CONTROL_SETTINGS = 0x0E, 339 340 // 1.0.2 record types 341 HPROF_HEAP_DUMP_SEGMENT = 0x1C, 342 HPROF_HEAP_DUMP_END = 0x2C, 343 344 // field types 345 HPROF_ARRAY_OBJECT = 0x01, 346 HPROF_NORMAL_OBJECT = 0x02, 347 HPROF_BOOLEAN = 0x04, 348 HPROF_CHAR = 0x05, 349 HPROF_FLOAT = 0x06, 350 HPROF_DOUBLE = 0x07, 351 HPROF_BYTE = 0x08, 352 HPROF_SHORT = 0x09, 353 HPROF_INT = 0x0A, 354 HPROF_LONG = 0x0B, 355 356 // data-dump sub-records 357 HPROF_GC_ROOT_UNKNOWN = 0xFF, 358 HPROF_GC_ROOT_JNI_GLOBAL = 0x01, 359 HPROF_GC_ROOT_JNI_LOCAL = 0x02, 360 HPROF_GC_ROOT_JAVA_FRAME = 0x03, 361 HPROF_GC_ROOT_NATIVE_STACK = 0x04, 362 HPROF_GC_ROOT_STICKY_CLASS = 0x05, 363 HPROF_GC_ROOT_THREAD_BLOCK = 0x06, 364 HPROF_GC_ROOT_MONITOR_USED = 0x07, 365 HPROF_GC_ROOT_THREAD_OBJ = 0x08, 366 HPROF_GC_CLASS_DUMP = 0x20, 367 HPROF_GC_INSTANCE_DUMP = 0x21, 368 HPROF_GC_OBJ_ARRAY_DUMP = 0x22, 369 HPROF_GC_PRIM_ARRAY_DUMP = 0x23 370 } hprofTag; 371 372 // Default stack trace ID (used for dummy HPROF_TRACE record) 373 enum { 374 STACK_TRACE_ID = 1, 375 INITIAL_CLASS_COUNT = 200 376 }; 377 378 // Supports I/O operations on a dump file 379 380 class DumpWriter : public StackObj { 381 private: 382 enum { 383 io_buffer_size = 8*M 384 }; 385 386 int _fd; // file descriptor (-1 if dump file not open) 387 julong _bytes_written; // number of byte written to dump file 388 389 char* _buffer; // internal buffer 390 size_t _size; 391 size_t _pos; 392 393 jlong _dump_start; 394 395 char* _error; // error message when I/O fails 396 397 void set_file_descriptor(int fd) { _fd = fd; } 398 int file_descriptor() const { return _fd; } 399 400 char* buffer() const { return _buffer; } 401 size_t buffer_size() const { return _size; } 402 size_t position() const { return _pos; } 403 void set_position(size_t pos) { _pos = pos; } 404 405 void set_error(const char* error) { _error = (char*)os::strdup(error); } 406 407 // all I/O go through this function 408 void write_internal(void* s, size_t len); 409 410 public: 411 DumpWriter(const char* path); 412 ~DumpWriter(); 413 414 void close(); 415 bool is_open() const { return file_descriptor() >= 0; } 416 void flush(); 417 418 jlong dump_start() const { return _dump_start; } 419 void set_dump_start(jlong pos); 420 julong current_record_length(); 421 422 // total number of bytes written to the disk 423 julong bytes_written() const { return _bytes_written; } 424 425 // adjust the number of bytes written to disk (used to keep the count 426 // of the number of bytes written in case of rewrites) 427 void adjust_bytes_written(jlong n) { _bytes_written += n; } 428 429 // number of (buffered) bytes as yet unwritten to the dump file 430 size_t bytes_unwritten() const { return position(); } 431 432 char* error() const { return _error; } 433 434 jlong current_offset(); 435 void seek_to_offset(jlong pos); 436 437 // writer functions 438 void write_raw(void* s, size_t len); 439 void write_u1(u1 x) { write_raw((void*)&x, 1); } 440 void write_u2(u2 x); 441 void write_u4(u4 x); 442 void write_u8(u8 x); 443 void write_objectID(oop o); 444 void write_symbolID(Symbol* o); 445 void write_classID(Klass* k); 446 void write_id(u4 x); 447 }; 448 449 DumpWriter::DumpWriter(const char* path) { 450 // try to allocate an I/O buffer of io_buffer_size. If there isn't 451 // sufficient memory then reduce size until we can allocate something. 452 _size = io_buffer_size; 453 do { 454 _buffer = (char*)os::malloc(_size, mtInternal); 455 if (_buffer == NULL) { 456 _size = _size >> 1; 457 } 458 } while (_buffer == NULL && _size > 0); 459 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check"); 460 _pos = 0; 461 _error = NULL; 462 _bytes_written = 0L; 463 _dump_start = (jlong)-1; 464 _fd = os::create_binary_file(path, false); // don't replace existing file 465 466 // if the open failed we record the error 467 if (_fd < 0) { 468 _error = (char*)os::strdup(os::strerror(errno)); 469 } 470 } 471 472 DumpWriter::~DumpWriter() { 473 // flush and close dump file 474 if (is_open()) { 475 close(); 476 } 477 if (_buffer != NULL) os::free(_buffer); 478 if (_error != NULL) os::free(_error); 479 } 480 481 // closes dump file (if open) 482 void DumpWriter::close() { 483 // flush and close dump file 484 if (is_open()) { 485 flush(); 486 os::close(file_descriptor()); 487 set_file_descriptor(-1); 488 } 489 } 490 491 // sets the dump starting position 492 void DumpWriter::set_dump_start(jlong pos) { 493 _dump_start = pos; 494 } 495 496 julong DumpWriter::current_record_length() { 497 if (is_open()) { 498 // calculate the size of the dump record 499 julong dump_end = bytes_written() + bytes_unwritten(); 500 assert(dump_end == (size_t)current_offset(), "checking"); 501 julong dump_len = dump_end - dump_start() - 4; 502 return dump_len; 503 } 504 return 0; 505 } 506 507 // write directly to the file 508 void DumpWriter::write_internal(void* s, size_t len) { 509 if (is_open()) { 510 const char* pos = (char*)s; 511 ssize_t n = 0; 512 while (len > 0) { 513 uint tmp = (uint)MIN2(len, (size_t)UINT_MAX); 514 n = os::write(file_descriptor(), pos, tmp); 515 516 if (n < 0) { 517 // EINTR cannot happen here, os::write will take care of that 518 set_error(os::strerror(errno)); 519 os::close(file_descriptor()); 520 set_file_descriptor(-1); 521 return; 522 } 523 524 _bytes_written += n; 525 pos += n; 526 len -= n; 527 } 528 } 529 } 530 531 // write raw bytes 532 void DumpWriter::write_raw(void* s, size_t len) { 533 if (is_open()) { 534 // flush buffer to make room 535 if ((position() + len) >= buffer_size()) { 536 flush(); 537 } 538 539 // buffer not available or too big to buffer it 540 if ((buffer() == NULL) || (len >= buffer_size())) { 541 write_internal(s, len); 542 } else { 543 // Should optimize this for u1/u2/u4/u8 sizes. 544 memcpy(buffer() + position(), s, len); 545 set_position(position() + len); 546 } 547 } 548 } 549 550 // flush any buffered bytes to the file 551 void DumpWriter::flush() { 552 if (is_open() && position() > 0) { 553 write_internal(buffer(), position()); 554 set_position(0); 555 } 556 } 557 558 jlong DumpWriter::current_offset() { 559 if (is_open()) { 560 // the offset is the file offset plus whatever we have buffered 561 jlong offset = os::current_file_offset(file_descriptor()); 562 assert(offset >= 0, "lseek failed"); 563 return offset + position(); 564 } else { 565 return (jlong)-1; 566 } 567 } 568 569 void DumpWriter::seek_to_offset(jlong off) { 570 assert(off >= 0, "bad offset"); 571 572 // need to flush before seeking 573 flush(); 574 575 // may be closed due to I/O error 576 if (is_open()) { 577 jlong n = os::seek_to_file_offset(file_descriptor(), off); 578 assert(n >= 0, "lseek failed"); 579 } 580 } 581 582 void DumpWriter::write_u2(u2 x) { 583 u2 v; 584 Bytes::put_Java_u2((address)&v, x); 585 write_raw((void*)&v, 2); 586 } 587 588 void DumpWriter::write_u4(u4 x) { 589 u4 v; 590 Bytes::put_Java_u4((address)&v, x); 591 write_raw((void*)&v, 4); 592 } 593 594 void DumpWriter::write_u8(u8 x) { 595 u8 v; 596 Bytes::put_Java_u8((address)&v, x); 597 write_raw((void*)&v, 8); 598 } 599 600 void DumpWriter::write_objectID(oop o) { 601 address a = (address)o; 602 #ifdef _LP64 603 write_u8((u8)a); 604 #else 605 write_u4((u4)a); 606 #endif 607 } 608 609 void DumpWriter::write_symbolID(Symbol* s) { 610 address a = (address)((uintptr_t)s); 611 #ifdef _LP64 612 write_u8((u8)a); 613 #else 614 write_u4((u4)a); 615 #endif 616 } 617 618 void DumpWriter::write_id(u4 x) { 619 #ifdef _LP64 620 write_u8((u8) x); 621 #else 622 write_u4(x); 623 #endif 624 } 625 626 // We use java mirror as the class ID 627 void DumpWriter::write_classID(Klass* k) { 628 write_objectID(k->java_mirror()); 629 } 630 631 632 633 // Support class with a collection of functions used when dumping the heap 634 635 class DumperSupport : AllStatic { 636 public: 637 638 // write a header of the given type 639 static void write_header(DumpWriter* writer, hprofTag tag, u4 len); 640 641 // returns hprof tag for the given type signature 642 static hprofTag sig2tag(Symbol* sig); 643 // returns hprof tag for the given basic type 644 static hprofTag type2tag(BasicType type); 645 646 // returns the size of the instance of the given class 647 static u4 instance_size(Klass* k); 648 649 // dump a jfloat 650 static void dump_float(DumpWriter* writer, jfloat f); 651 // dump a jdouble 652 static void dump_double(DumpWriter* writer, jdouble d); 653 // dumps the raw value of the given field 654 static void dump_field_value(DumpWriter* writer, char type, oop obj, int offset); 655 // dumps static fields of the given class 656 static void dump_static_fields(DumpWriter* writer, Klass* k); 657 // dump the raw values of the instance fields of the given object 658 static void dump_instance_fields(DumpWriter* writer, oop o); 659 // dumps the definition of the instance fields for a given class 660 static void dump_instance_field_descriptors(DumpWriter* writer, Klass* k); 661 // creates HPROF_GC_INSTANCE_DUMP record for the given object 662 static void dump_instance(DumpWriter* writer, oop o); 663 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its 664 // array classes 665 static void dump_class_and_array_classes(DumpWriter* writer, Klass* k); 666 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 667 // class (and each multi-dimensional array class too) 668 static void dump_basic_type_array_class(DumpWriter* writer, Klass* k); 669 670 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 671 static void dump_object_array(DumpWriter* writer, objArrayOop array); 672 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 673 static void dump_prim_array(DumpWriter* writer, typeArrayOop array); 674 // create HPROF_FRAME record for the given method and bci 675 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci); 676 677 // check if we need to truncate an array 678 static int calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size); 679 680 // writes a HPROF_HEAP_DUMP_SEGMENT record 681 static void write_dump_header(DumpWriter* writer); 682 683 // fixes up the length of the current dump record 684 static void write_current_dump_record_length(DumpWriter* writer); 685 686 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record 687 static void end_of_dump(DumpWriter* writer); 688 }; 689 690 // write a header of the given type 691 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) { 692 writer->write_u1((u1)tag); 693 writer->write_u4(0); // current ticks 694 writer->write_u4(len); 695 } 696 697 // returns hprof tag for the given type signature 698 hprofTag DumperSupport::sig2tag(Symbol* sig) { 699 switch (sig->byte_at(0)) { 700 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT; 701 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT; 702 case JVM_SIGNATURE_BYTE : return HPROF_BYTE; 703 case JVM_SIGNATURE_CHAR : return HPROF_CHAR; 704 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT; 705 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE; 706 case JVM_SIGNATURE_INT : return HPROF_INT; 707 case JVM_SIGNATURE_LONG : return HPROF_LONG; 708 case JVM_SIGNATURE_SHORT : return HPROF_SHORT; 709 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN; 710 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 711 } 712 } 713 714 hprofTag DumperSupport::type2tag(BasicType type) { 715 switch (type) { 716 case T_BYTE : return HPROF_BYTE; 717 case T_CHAR : return HPROF_CHAR; 718 case T_FLOAT : return HPROF_FLOAT; 719 case T_DOUBLE : return HPROF_DOUBLE; 720 case T_INT : return HPROF_INT; 721 case T_LONG : return HPROF_LONG; 722 case T_SHORT : return HPROF_SHORT; 723 case T_BOOLEAN : return HPROF_BOOLEAN; 724 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 725 } 726 } 727 728 // dump a jfloat 729 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) { 730 if (g_isnan(f)) { 731 writer->write_u4(0x7fc00000); // collapsing NaNs 732 } else { 733 union { 734 int i; 735 float f; 736 } u; 737 u.f = (float)f; 738 writer->write_u4((u4)u.i); 739 } 740 } 741 742 // dump a jdouble 743 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) { 744 union { 745 jlong l; 746 double d; 747 } u; 748 if (g_isnan(d)) { // collapsing NaNs 749 u.l = (jlong)(0x7ff80000); 750 u.l = (u.l << 32); 751 } else { 752 u.d = (double)d; 753 } 754 writer->write_u8((u8)u.l); 755 } 756 757 // dumps the raw value of the given field 758 void DumperSupport::dump_field_value(DumpWriter* writer, char type, oop obj, int offset) { 759 switch (type) { 760 case JVM_SIGNATURE_CLASS : 761 case JVM_SIGNATURE_ARRAY : { 762 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF>(offset); 763 assert(oopDesc::is_oop_or_null(o), "Expected an oop or NULL at " PTR_FORMAT, p2i(o)); 764 writer->write_objectID(o); 765 break; 766 } 767 case JVM_SIGNATURE_BYTE : { 768 jbyte b = obj->byte_field(offset); 769 writer->write_u1((u1)b); 770 break; 771 } 772 case JVM_SIGNATURE_CHAR : { 773 jchar c = obj->char_field(offset); 774 writer->write_u2((u2)c); 775 break; 776 } 777 case JVM_SIGNATURE_SHORT : { 778 jshort s = obj->short_field(offset); 779 writer->write_u2((u2)s); 780 break; 781 } 782 case JVM_SIGNATURE_FLOAT : { 783 jfloat f = obj->float_field(offset); 784 dump_float(writer, f); 785 break; 786 } 787 case JVM_SIGNATURE_DOUBLE : { 788 jdouble d = obj->double_field(offset); 789 dump_double(writer, d); 790 break; 791 } 792 case JVM_SIGNATURE_INT : { 793 jint i = obj->int_field(offset); 794 writer->write_u4((u4)i); 795 break; 796 } 797 case JVM_SIGNATURE_LONG : { 798 jlong l = obj->long_field(offset); 799 writer->write_u8((u8)l); 800 break; 801 } 802 case JVM_SIGNATURE_BOOLEAN : { 803 jboolean b = obj->bool_field(offset); 804 writer->write_u1((u1)b); 805 break; 806 } 807 default : { 808 ShouldNotReachHere(); 809 break; 810 } 811 } 812 } 813 814 // returns the size of the instance of the given class 815 u4 DumperSupport::instance_size(Klass* k) { 816 HandleMark hm; 817 InstanceKlass* ik = InstanceKlass::cast(k); 818 819 u4 size = 0; 820 821 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) { 822 if (!fld.access_flags().is_static()) { 823 Symbol* sig = fld.signature(); 824 switch (sig->byte_at(0)) { 825 case JVM_SIGNATURE_CLASS : 826 case JVM_SIGNATURE_ARRAY : size += oopSize; break; 827 828 case JVM_SIGNATURE_BYTE : 829 case JVM_SIGNATURE_BOOLEAN : size += 1; break; 830 831 case JVM_SIGNATURE_CHAR : 832 case JVM_SIGNATURE_SHORT : size += 2; break; 833 834 case JVM_SIGNATURE_INT : 835 case JVM_SIGNATURE_FLOAT : size += 4; break; 836 837 case JVM_SIGNATURE_LONG : 838 case JVM_SIGNATURE_DOUBLE : size += 8; break; 839 840 default : ShouldNotReachHere(); 841 } 842 } 843 } 844 return size; 845 } 846 847 // dumps static fields of the given class 848 void DumperSupport::dump_static_fields(DumpWriter* writer, Klass* k) { 849 HandleMark hm; 850 InstanceKlass* ik = InstanceKlass::cast(k); 851 852 // pass 1 - count the static fields 853 u2 field_count = 0; 854 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) { 855 if (fldc.access_flags().is_static()) field_count++; 856 } 857 858 // Add in resolved_references which is referenced by the cpCache 859 // The resolved_references is an array per InstanceKlass holding the 860 // strings and other oops resolved from the constant pool. 861 oop resolved_references = ik->constants()->resolved_references_or_null(); 862 if (resolved_references != NULL) { 863 field_count++; 864 865 // Add in the resolved_references of the used previous versions of the class 866 // in the case of RedefineClasses 867 InstanceKlass* prev = ik->previous_versions(); 868 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) { 869 field_count++; 870 prev = prev->previous_versions(); 871 } 872 } 873 874 // Also provide a pointer to the init_lock if present, so there aren't unreferenced int[0] 875 // arrays. 876 oop init_lock = ik->init_lock(); 877 if (init_lock != NULL) { 878 field_count++; 879 } 880 881 writer->write_u2(field_count); 882 883 // pass 2 - dump the field descriptors and raw values 884 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) { 885 if (fld.access_flags().is_static()) { 886 Symbol* sig = fld.signature(); 887 888 writer->write_symbolID(fld.name()); // name 889 writer->write_u1(sig2tag(sig)); // type 890 891 // value 892 dump_field_value(writer, sig->byte_at(0), ik->java_mirror(), fld.offset()); 893 } 894 } 895 896 // Add resolved_references for each class that has them 897 if (resolved_references != NULL) { 898 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 899 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 900 writer->write_objectID(resolved_references); 901 902 // Also write any previous versions 903 InstanceKlass* prev = ik->previous_versions(); 904 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) { 905 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 906 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 907 writer->write_objectID(prev->constants()->resolved_references()); 908 prev = prev->previous_versions(); 909 } 910 } 911 912 // Add init lock to the end if the class is not yet initialized 913 if (init_lock != NULL) { 914 writer->write_symbolID(vmSymbols::init_lock_name()); // name 915 writer->write_u1(sig2tag(vmSymbols::int_array_signature())); // type 916 writer->write_objectID(init_lock); 917 } 918 } 919 920 // dump the raw values of the instance fields of the given object 921 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) { 922 HandleMark hm; 923 InstanceKlass* ik = InstanceKlass::cast(o->klass()); 924 925 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) { 926 if (!fld.access_flags().is_static()) { 927 Symbol* sig = fld.signature(); 928 dump_field_value(writer, sig->byte_at(0), o, fld.offset()); 929 } 930 } 931 } 932 933 // dumps the definition of the instance fields for a given class 934 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, Klass* k) { 935 HandleMark hm; 936 InstanceKlass* ik = InstanceKlass::cast(k); 937 938 // pass 1 - count the instance fields 939 u2 field_count = 0; 940 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) { 941 if (!fldc.access_flags().is_static()) field_count++; 942 } 943 944 writer->write_u2(field_count); 945 946 // pass 2 - dump the field descriptors 947 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) { 948 if (!fld.access_flags().is_static()) { 949 Symbol* sig = fld.signature(); 950 951 writer->write_symbolID(fld.name()); // name 952 writer->write_u1(sig2tag(sig)); // type 953 } 954 } 955 } 956 957 // creates HPROF_GC_INSTANCE_DUMP record for the given object 958 void DumperSupport::dump_instance(DumpWriter* writer, oop o) { 959 Klass* k = o->klass(); 960 961 writer->write_u1(HPROF_GC_INSTANCE_DUMP); 962 writer->write_objectID(o); 963 writer->write_u4(STACK_TRACE_ID); 964 965 // class ID 966 writer->write_classID(k); 967 968 // number of bytes that follow 969 writer->write_u4(instance_size(k) ); 970 971 // field values 972 dump_instance_fields(writer, o); 973 } 974 975 // creates HPROF_GC_CLASS_DUMP record for the given class and each of 976 // its array classes 977 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, Klass* k) { 978 InstanceKlass* ik = InstanceKlass::cast(k); 979 980 // We can safepoint and do a heap dump at a point where we have a Klass, 981 // but no java mirror class has been setup for it. So we need to check 982 // that the class is at least loaded, to avoid crash from a null mirror. 983 if (!ik->is_loaded()) { 984 return; 985 } 986 987 writer->write_u1(HPROF_GC_CLASS_DUMP); 988 989 // class ID 990 writer->write_classID(ik); 991 writer->write_u4(STACK_TRACE_ID); 992 993 // super class ID 994 InstanceKlass* java_super = ik->java_super(); 995 if (java_super == NULL) { 996 writer->write_objectID(oop(NULL)); 997 } else { 998 writer->write_classID(java_super); 999 } 1000 1001 writer->write_objectID(ik->class_loader()); 1002 writer->write_objectID(ik->signers()); 1003 writer->write_objectID(ik->protection_domain()); 1004 1005 // reserved 1006 writer->write_objectID(oop(NULL)); 1007 writer->write_objectID(oop(NULL)); 1008 1009 // instance size 1010 writer->write_u4(DumperSupport::instance_size(k)); 1011 1012 // size of constant pool - ignored by HAT 1.1 1013 writer->write_u2(0); 1014 1015 // number of static fields 1016 dump_static_fields(writer, k); 1017 1018 // description of instance fields 1019 dump_instance_field_descriptors(writer, k); 1020 1021 // array classes 1022 k = k->array_klass_or_null(); 1023 while (k != NULL) { 1024 Klass* klass = k; 1025 assert(klass->is_objArray_klass(), "not an ObjArrayKlass"); 1026 1027 writer->write_u1(HPROF_GC_CLASS_DUMP); 1028 writer->write_classID(klass); 1029 writer->write_u4(STACK_TRACE_ID); 1030 1031 // super class of array classes is java.lang.Object 1032 java_super = klass->java_super(); 1033 assert(java_super != NULL, "checking"); 1034 writer->write_classID(java_super); 1035 1036 writer->write_objectID(ik->class_loader()); 1037 writer->write_objectID(ik->signers()); 1038 writer->write_objectID(ik->protection_domain()); 1039 1040 writer->write_objectID(oop(NULL)); // reserved 1041 writer->write_objectID(oop(NULL)); 1042 writer->write_u4(0); // instance size 1043 writer->write_u2(0); // constant pool 1044 writer->write_u2(0); // static fields 1045 writer->write_u2(0); // instance fields 1046 1047 // get the array class for the next rank 1048 k = klass->array_klass_or_null(); 1049 } 1050 } 1051 1052 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 1053 // class (and each multi-dimensional array class too) 1054 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, Klass* k) { 1055 // array classes 1056 while (k != NULL) { 1057 Klass* klass = k; 1058 1059 writer->write_u1(HPROF_GC_CLASS_DUMP); 1060 writer->write_classID(klass); 1061 writer->write_u4(STACK_TRACE_ID); 1062 1063 // super class of array classes is java.lang.Object 1064 InstanceKlass* java_super = klass->java_super(); 1065 assert(java_super != NULL, "checking"); 1066 writer->write_classID(java_super); 1067 1068 writer->write_objectID(oop(NULL)); // loader 1069 writer->write_objectID(oop(NULL)); // signers 1070 writer->write_objectID(oop(NULL)); // protection domain 1071 1072 writer->write_objectID(oop(NULL)); // reserved 1073 writer->write_objectID(oop(NULL)); 1074 writer->write_u4(0); // instance size 1075 writer->write_u2(0); // constant pool 1076 writer->write_u2(0); // static fields 1077 writer->write_u2(0); // instance fields 1078 1079 // get the array class for the next rank 1080 k = klass->array_klass_or_null(); 1081 } 1082 } 1083 1084 // Hprof uses an u4 as record length field, 1085 // which means we need to truncate arrays that are too long. 1086 int DumperSupport::calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size) { 1087 BasicType type = ArrayKlass::cast(array->klass())->element_type(); 1088 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type"); 1089 1090 int length = array->length(); 1091 1092 int type_size; 1093 if (type == T_OBJECT) { 1094 type_size = sizeof(address); 1095 } else { 1096 type_size = type2aelembytes(type); 1097 } 1098 1099 size_t length_in_bytes = (size_t)length * type_size; 1100 1101 // Create a new record if the current record is non-empty and the array can't fit. 1102 julong current_record_length = writer->current_record_length(); 1103 if (current_record_length > 0 && 1104 (current_record_length + header_size + length_in_bytes) > max_juint) { 1105 write_current_dump_record_length(writer); 1106 write_dump_header(writer); 1107 1108 // We now have an empty record. 1109 current_record_length = 0; 1110 } 1111 1112 // Calculate max bytes we can use. 1113 uint max_bytes = max_juint - (header_size + current_record_length); 1114 1115 // Array too long for the record? 1116 // Calculate max length and return it. 1117 if (length_in_bytes > max_bytes) { 1118 length = max_bytes / type_size; 1119 length_in_bytes = (size_t)length * type_size; 1120 1121 warning("cannot dump array of type %s[] with length %d; truncating to length %d", 1122 type2name_tab[type], array->length(), length); 1123 } 1124 return length; 1125 } 1126 1127 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 1128 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) { 1129 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID) 1130 short header_size = 1 + 2 * 4 + 2 * sizeof(address); 1131 1132 int length = calculate_array_max_length(writer, array, header_size); 1133 1134 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP); 1135 writer->write_objectID(array); 1136 writer->write_u4(STACK_TRACE_ID); 1137 writer->write_u4(length); 1138 1139 // array class ID 1140 writer->write_classID(array->klass()); 1141 1142 // [id]* elements 1143 for (int index = 0; index < length; index++) { 1144 oop o = array->obj_at(index); 1145 writer->write_objectID(o); 1146 } 1147 } 1148 1149 #define WRITE_ARRAY(Array, Type, Size, Length) \ 1150 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); } 1151 1152 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 1153 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) { 1154 BasicType type = TypeArrayKlass::cast(array->klass())->element_type(); 1155 1156 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) 1157 short header_size = 2 * 1 + 2 * 4 + sizeof(address); 1158 1159 int length = calculate_array_max_length(writer, array, header_size); 1160 int type_size = type2aelembytes(type); 1161 u4 length_in_bytes = (u4)length * type_size; 1162 1163 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP); 1164 writer->write_objectID(array); 1165 writer->write_u4(STACK_TRACE_ID); 1166 writer->write_u4(length); 1167 writer->write_u1(type2tag(type)); 1168 1169 // nothing to copy 1170 if (length == 0) { 1171 return; 1172 } 1173 1174 // If the byte ordering is big endian then we can copy most types directly 1175 1176 switch (type) { 1177 case T_INT : { 1178 if (Endian::is_Java_byte_ordering_different()) { 1179 WRITE_ARRAY(array, int, u4, length); 1180 } else { 1181 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes); 1182 } 1183 break; 1184 } 1185 case T_BYTE : { 1186 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes); 1187 break; 1188 } 1189 case T_CHAR : { 1190 if (Endian::is_Java_byte_ordering_different()) { 1191 WRITE_ARRAY(array, char, u2, length); 1192 } else { 1193 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes); 1194 } 1195 break; 1196 } 1197 case T_SHORT : { 1198 if (Endian::is_Java_byte_ordering_different()) { 1199 WRITE_ARRAY(array, short, u2, length); 1200 } else { 1201 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes); 1202 } 1203 break; 1204 } 1205 case T_BOOLEAN : { 1206 if (Endian::is_Java_byte_ordering_different()) { 1207 WRITE_ARRAY(array, bool, u1, length); 1208 } else { 1209 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes); 1210 } 1211 break; 1212 } 1213 case T_LONG : { 1214 if (Endian::is_Java_byte_ordering_different()) { 1215 WRITE_ARRAY(array, long, u8, length); 1216 } else { 1217 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes); 1218 } 1219 break; 1220 } 1221 1222 // handle float/doubles in a special value to ensure than NaNs are 1223 // written correctly. TO DO: Check if we can avoid this on processors that 1224 // use IEEE 754. 1225 1226 case T_FLOAT : { 1227 for (int i = 0; i < length; i++) { 1228 dump_float(writer, array->float_at(i)); 1229 } 1230 break; 1231 } 1232 case T_DOUBLE : { 1233 for (int i = 0; i < length; i++) { 1234 dump_double(writer, array->double_at(i)); 1235 } 1236 break; 1237 } 1238 default : ShouldNotReachHere(); 1239 } 1240 } 1241 1242 // create a HPROF_FRAME record of the given Method* and bci 1243 void DumperSupport::dump_stack_frame(DumpWriter* writer, 1244 int frame_serial_num, 1245 int class_serial_num, 1246 Method* m, 1247 int bci) { 1248 int line_number; 1249 if (m->is_native()) { 1250 line_number = -3; // native frame 1251 } else { 1252 line_number = m->line_number_from_bci(bci); 1253 } 1254 1255 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4)); 1256 writer->write_id(frame_serial_num); // frame serial number 1257 writer->write_symbolID(m->name()); // method's name 1258 writer->write_symbolID(m->signature()); // method's signature 1259 1260 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass"); 1261 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name 1262 writer->write_u4(class_serial_num); // class serial number 1263 writer->write_u4((u4) line_number); // line number 1264 } 1265 1266 1267 // Support class used to generate HPROF_UTF8 records from the entries in the 1268 // SymbolTable. 1269 1270 class SymbolTableDumper : public SymbolClosure { 1271 private: 1272 DumpWriter* _writer; 1273 DumpWriter* writer() const { return _writer; } 1274 public: 1275 SymbolTableDumper(DumpWriter* writer) { _writer = writer; } 1276 void do_symbol(Symbol** p); 1277 }; 1278 1279 void SymbolTableDumper::do_symbol(Symbol** p) { 1280 ResourceMark rm; 1281 Symbol* sym = load_symbol(p); 1282 int len = sym->utf8_length(); 1283 if (len > 0) { 1284 char* s = sym->as_utf8(); 1285 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len); 1286 writer()->write_symbolID(sym); 1287 writer()->write_raw(s, len); 1288 } 1289 } 1290 1291 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records 1292 1293 class JNILocalsDumper : public OopClosure { 1294 private: 1295 DumpWriter* _writer; 1296 u4 _thread_serial_num; 1297 int _frame_num; 1298 DumpWriter* writer() const { return _writer; } 1299 public: 1300 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) { 1301 _writer = writer; 1302 _thread_serial_num = thread_serial_num; 1303 _frame_num = -1; // default - empty stack 1304 } 1305 void set_frame_number(int n) { _frame_num = n; } 1306 void do_oop(oop* obj_p); 1307 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1308 }; 1309 1310 1311 void JNILocalsDumper::do_oop(oop* obj_p) { 1312 // ignore null handles 1313 oop o = *obj_p; 1314 if (o != NULL) { 1315 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL); 1316 writer()->write_objectID(o); 1317 writer()->write_u4(_thread_serial_num); 1318 writer()->write_u4((u4)_frame_num); 1319 } 1320 } 1321 1322 1323 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records 1324 1325 class JNIGlobalsDumper : public OopClosure { 1326 private: 1327 DumpWriter* _writer; 1328 DumpWriter* writer() const { return _writer; } 1329 1330 public: 1331 JNIGlobalsDumper(DumpWriter* writer) { 1332 _writer = writer; 1333 } 1334 void do_oop(oop* obj_p); 1335 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1336 }; 1337 1338 void JNIGlobalsDumper::do_oop(oop* obj_p) { 1339 oop o = *obj_p; 1340 1341 // ignore these 1342 if (o == NULL) return; 1343 1344 // we ignore global ref to symbols and other internal objects 1345 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) { 1346 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL); 1347 writer()->write_objectID(o); 1348 writer()->write_objectID((oopDesc*)obj_p); // global ref ID 1349 } 1350 }; 1351 1352 1353 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records 1354 1355 class MonitorUsedDumper : public OopClosure { 1356 private: 1357 DumpWriter* _writer; 1358 DumpWriter* writer() const { return _writer; } 1359 public: 1360 MonitorUsedDumper(DumpWriter* writer) { 1361 _writer = writer; 1362 } 1363 void do_oop(oop* obj_p) { 1364 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED); 1365 writer()->write_objectID(*obj_p); 1366 } 1367 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1368 }; 1369 1370 1371 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records 1372 1373 class StickyClassDumper : public KlassClosure { 1374 private: 1375 DumpWriter* _writer; 1376 DumpWriter* writer() const { return _writer; } 1377 public: 1378 StickyClassDumper(DumpWriter* writer) { 1379 _writer = writer; 1380 } 1381 void do_klass(Klass* k) { 1382 if (k->is_instance_klass()) { 1383 InstanceKlass* ik = InstanceKlass::cast(k); 1384 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS); 1385 writer()->write_classID(ik); 1386 } 1387 } 1388 }; 1389 1390 1391 class VM_HeapDumper; 1392 1393 // Support class using when iterating over the heap. 1394 1395 class HeapObjectDumper : public ObjectClosure { 1396 private: 1397 VM_HeapDumper* _dumper; 1398 DumpWriter* _writer; 1399 1400 VM_HeapDumper* dumper() { return _dumper; } 1401 DumpWriter* writer() { return _writer; } 1402 1403 // used to indicate that a record has been writen 1404 void mark_end_of_record(); 1405 1406 public: 1407 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) { 1408 _dumper = dumper; 1409 _writer = writer; 1410 } 1411 1412 // called for each object in the heap 1413 void do_object(oop o); 1414 }; 1415 1416 void HeapObjectDumper::do_object(oop o) { 1417 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records 1418 if (o->klass() == SystemDictionary::Class_klass()) { 1419 if (!java_lang_Class::is_primitive(o)) { 1420 return; 1421 } 1422 } 1423 1424 if (o->is_instance()) { 1425 // create a HPROF_GC_INSTANCE record for each object 1426 DumperSupport::dump_instance(writer(), o); 1427 mark_end_of_record(); 1428 } else if (o->is_objArray()) { 1429 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array 1430 DumperSupport::dump_object_array(writer(), objArrayOop(o)); 1431 mark_end_of_record(); 1432 } else if (o->is_typeArray()) { 1433 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array 1434 DumperSupport::dump_prim_array(writer(), typeArrayOop(o)); 1435 mark_end_of_record(); 1436 } 1437 } 1438 1439 // The VM operation that performs the heap dump 1440 class VM_HeapDumper : public VM_GC_Operation { 1441 private: 1442 static VM_HeapDumper* _global_dumper; 1443 static DumpWriter* _global_writer; 1444 DumpWriter* _local_writer; 1445 JavaThread* _oome_thread; 1446 Method* _oome_constructor; 1447 bool _gc_before_heap_dump; 1448 GrowableArray<Klass*>* _klass_map; 1449 ThreadStackTrace** _stack_traces; 1450 int _num_threads; 1451 1452 // accessors and setters 1453 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; } 1454 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; } 1455 void set_global_dumper() { 1456 assert(_global_dumper == NULL, "Error"); 1457 _global_dumper = this; 1458 } 1459 void set_global_writer() { 1460 assert(_global_writer == NULL, "Error"); 1461 _global_writer = _local_writer; 1462 } 1463 void clear_global_dumper() { _global_dumper = NULL; } 1464 void clear_global_writer() { _global_writer = NULL; } 1465 1466 bool skip_operation() const; 1467 1468 // writes a HPROF_LOAD_CLASS record 1469 class ClassesDo; 1470 static void do_load_class(Klass* k); 1471 1472 // writes a HPROF_GC_CLASS_DUMP record for the given class 1473 // (and each array class too) 1474 static void do_class_dump(Klass* k); 1475 1476 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1477 // array (and each multi-dimensional array too) 1478 static void do_basic_type_array_class_dump(Klass* k); 1479 1480 // HPROF_GC_ROOT_THREAD_OBJ records 1481 int do_thread(JavaThread* thread, u4 thread_serial_num); 1482 void do_threads(); 1483 1484 void add_class_serial_number(Klass* k, int serial_num) { 1485 _klass_map->at_put_grow(serial_num, k); 1486 } 1487 1488 // HPROF_TRACE and HPROF_FRAME records 1489 void dump_stack_traces(); 1490 1491 public: 1492 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) : 1493 VM_GC_Operation(0 /* total collections, dummy, ignored */, 1494 GCCause::_heap_dump /* GC Cause */, 1495 0 /* total full collections, dummy, ignored */, 1496 gc_before_heap_dump) { 1497 _local_writer = writer; 1498 _gc_before_heap_dump = gc_before_heap_dump; 1499 _klass_map = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true); 1500 _stack_traces = NULL; 1501 _num_threads = 0; 1502 if (oome) { 1503 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread"); 1504 // get OutOfMemoryError zero-parameter constructor 1505 InstanceKlass* oome_ik = SystemDictionary::OutOfMemoryError_klass(); 1506 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(), 1507 vmSymbols::void_method_signature()); 1508 // get thread throwing OOME when generating the heap dump at OOME 1509 _oome_thread = JavaThread::current(); 1510 } else { 1511 _oome_thread = NULL; 1512 _oome_constructor = NULL; 1513 } 1514 } 1515 ~VM_HeapDumper() { 1516 if (_stack_traces != NULL) { 1517 for (int i=0; i < _num_threads; i++) { 1518 delete _stack_traces[i]; 1519 } 1520 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces); 1521 } 1522 delete _klass_map; 1523 } 1524 1525 VMOp_Type type() const { return VMOp_HeapDumper; } 1526 // used to mark sub-record boundary 1527 void check_segment_length(); 1528 void doit(); 1529 }; 1530 1531 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL; 1532 DumpWriter* VM_HeapDumper::_global_writer = NULL; 1533 1534 bool VM_HeapDumper::skip_operation() const { 1535 return false; 1536 } 1537 1538 // writes a HPROF_HEAP_DUMP_SEGMENT record 1539 void DumperSupport::write_dump_header(DumpWriter* writer) { 1540 if (writer->is_open()) { 1541 writer->write_u1(HPROF_HEAP_DUMP_SEGMENT); 1542 writer->write_u4(0); // current ticks 1543 1544 // record the starting position for the dump (its length will be fixed up later) 1545 writer->set_dump_start(writer->current_offset()); 1546 writer->write_u4(0); 1547 } 1548 } 1549 1550 // fixes up the length of the current dump record 1551 void DumperSupport::write_current_dump_record_length(DumpWriter* writer) { 1552 if (writer->is_open()) { 1553 julong dump_end = writer->bytes_written() + writer->bytes_unwritten(); 1554 julong dump_len = writer->current_record_length(); 1555 1556 // record length must fit in a u4 1557 if (dump_len > max_juint) { 1558 warning("record is too large"); 1559 } 1560 1561 // seek to the dump start and fix-up the length 1562 assert(writer->dump_start() >= 0, "no dump start recorded"); 1563 writer->seek_to_offset(writer->dump_start()); 1564 writer->write_u4((u4)dump_len); 1565 1566 // adjust the total size written to keep the bytes written correct. 1567 writer->adjust_bytes_written(-((jlong) sizeof(u4))); 1568 1569 // seek to dump end so we can continue 1570 writer->seek_to_offset(dump_end); 1571 1572 // no current dump record 1573 writer->set_dump_start((jlong)-1); 1574 } 1575 } 1576 1577 // used on a sub-record boundary to check if we need to start a 1578 // new segment. 1579 void VM_HeapDumper::check_segment_length() { 1580 if (writer()->is_open()) { 1581 julong dump_len = writer()->current_record_length(); 1582 1583 if (dump_len > 2UL*G) { 1584 DumperSupport::write_current_dump_record_length(writer()); 1585 DumperSupport::write_dump_header(writer()); 1586 } 1587 } 1588 } 1589 1590 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record 1591 void DumperSupport::end_of_dump(DumpWriter* writer) { 1592 if (writer->is_open()) { 1593 write_current_dump_record_length(writer); 1594 1595 writer->write_u1(HPROF_HEAP_DUMP_END); 1596 writer->write_u4(0); 1597 writer->write_u4(0); 1598 } 1599 } 1600 1601 // marks sub-record boundary 1602 void HeapObjectDumper::mark_end_of_record() { 1603 dumper()->check_segment_length(); 1604 } 1605 1606 // writes a HPROF_LOAD_CLASS record for the class (and each of its 1607 // array classes) 1608 void VM_HeapDumper::do_load_class(Klass* k) { 1609 static u4 class_serial_num = 0; 1610 1611 // len of HPROF_LOAD_CLASS record 1612 u4 remaining = 2*oopSize + 2*sizeof(u4); 1613 1614 // write a HPROF_LOAD_CLASS for the class and each array class 1615 do { 1616 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining); 1617 1618 // class serial number is just a number 1619 writer()->write_u4(++class_serial_num); 1620 1621 // class ID 1622 Klass* klass = k; 1623 writer()->write_classID(klass); 1624 1625 // add the Klass* and class serial number pair 1626 dumper()->add_class_serial_number(klass, class_serial_num); 1627 1628 writer()->write_u4(STACK_TRACE_ID); 1629 1630 // class name ID 1631 Symbol* name = klass->name(); 1632 writer()->write_symbolID(name); 1633 1634 // write a LOAD_CLASS record for the array type (if it exists) 1635 k = klass->array_klass_or_null(); 1636 } while (k != NULL); 1637 } 1638 1639 // writes a HPROF_GC_CLASS_DUMP record for the given class 1640 void VM_HeapDumper::do_class_dump(Klass* k) { 1641 if (k->is_instance_klass()) { 1642 DumperSupport::dump_class_and_array_classes(writer(), k); 1643 } 1644 } 1645 1646 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1647 // array (and each multi-dimensional array too) 1648 void VM_HeapDumper::do_basic_type_array_class_dump(Klass* k) { 1649 DumperSupport::dump_basic_type_array_class(writer(), k); 1650 } 1651 1652 // Walk the stack of the given thread. 1653 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local 1654 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local 1655 // 1656 // It returns the number of Java frames in this thread stack 1657 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) { 1658 JNILocalsDumper blk(writer(), thread_serial_num); 1659 1660 oop threadObj = java_thread->threadObj(); 1661 assert(threadObj != NULL, "sanity check"); 1662 1663 int stack_depth = 0; 1664 if (java_thread->has_last_Java_frame()) { 1665 1666 // vframes are resource allocated 1667 Thread* current_thread = Thread::current(); 1668 ResourceMark rm(current_thread); 1669 HandleMark hm(current_thread); 1670 1671 RegisterMap reg_map(java_thread); 1672 frame f = java_thread->last_frame(); 1673 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread); 1674 frame* last_entry_frame = NULL; 1675 int extra_frames = 0; 1676 1677 if (java_thread == _oome_thread && _oome_constructor != NULL) { 1678 extra_frames++; 1679 } 1680 while (vf != NULL) { 1681 blk.set_frame_number(stack_depth); 1682 if (vf->is_java_frame()) { 1683 1684 // java frame (interpreted, compiled, ...) 1685 javaVFrame *jvf = javaVFrame::cast(vf); 1686 if (!(jvf->method()->is_native())) { 1687 StackValueCollection* locals = jvf->locals(); 1688 for (int slot=0; slot<locals->size(); slot++) { 1689 if (locals->at(slot)->type() == T_OBJECT) { 1690 oop o = locals->obj_at(slot)(); 1691 1692 if (o != NULL) { 1693 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME); 1694 writer()->write_objectID(o); 1695 writer()->write_u4(thread_serial_num); 1696 writer()->write_u4((u4) (stack_depth + extra_frames)); 1697 } 1698 } 1699 } 1700 StackValueCollection *exprs = jvf->expressions(); 1701 for(int index = 0; index < exprs->size(); index++) { 1702 if (exprs->at(index)->type() == T_OBJECT) { 1703 oop o = exprs->obj_at(index)(); 1704 if (o != NULL) { 1705 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME); 1706 writer()->write_objectID(o); 1707 writer()->write_u4(thread_serial_num); 1708 writer()->write_u4((u4) (stack_depth + extra_frames)); 1709 } 1710 } 1711 } 1712 } else { 1713 // native frame 1714 if (stack_depth == 0) { 1715 // JNI locals for the top frame. 1716 java_thread->active_handles()->oops_do(&blk); 1717 } else { 1718 if (last_entry_frame != NULL) { 1719 // JNI locals for the entry frame 1720 assert(last_entry_frame->is_entry_frame(), "checking"); 1721 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk); 1722 } 1723 } 1724 } 1725 // increment only for Java frames 1726 stack_depth++; 1727 last_entry_frame = NULL; 1728 1729 } else { 1730 // externalVFrame - if it's an entry frame then report any JNI locals 1731 // as roots when we find the corresponding native javaVFrame 1732 frame* fr = vf->frame_pointer(); 1733 assert(fr != NULL, "sanity check"); 1734 if (fr->is_entry_frame()) { 1735 last_entry_frame = fr; 1736 } 1737 } 1738 vf = vf->sender(); 1739 } 1740 } else { 1741 // no last java frame but there may be JNI locals 1742 java_thread->active_handles()->oops_do(&blk); 1743 } 1744 return stack_depth; 1745 } 1746 1747 1748 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk 1749 // the stack so that locals and JNI locals are dumped. 1750 void VM_HeapDumper::do_threads() { 1751 for (int i=0; i < _num_threads; i++) { 1752 JavaThread* thread = _stack_traces[i]->thread(); 1753 oop threadObj = thread->threadObj(); 1754 u4 thread_serial_num = i+1; 1755 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID; 1756 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ); 1757 writer()->write_objectID(threadObj); 1758 writer()->write_u4(thread_serial_num); // thread number 1759 writer()->write_u4(stack_serial_num); // stack trace serial number 1760 int num_frames = do_thread(thread, thread_serial_num); 1761 assert(num_frames == _stack_traces[i]->get_stack_depth(), 1762 "total number of Java frames not matched"); 1763 } 1764 } 1765 1766 1767 // The VM operation that dumps the heap. The dump consists of the following 1768 // records: 1769 // 1770 // HPROF_HEADER 1771 // [HPROF_UTF8]* 1772 // [HPROF_LOAD_CLASS]* 1773 // [[HPROF_FRAME]*|HPROF_TRACE]* 1774 // [HPROF_GC_CLASS_DUMP]* 1775 // [HPROF_HEAP_DUMP_SEGMENT]* 1776 // HPROF_HEAP_DUMP_END 1777 // 1778 // The HPROF_TRACE records represent the stack traces where the heap dump 1779 // is generated and a "dummy trace" record which does not include 1780 // any frames. The dummy trace record is used to be referenced as the 1781 // unknown object alloc site. 1782 // 1783 // Each HPROF_HEAP_DUMP_SEGMENT record has a length followed by sub-records. 1784 // To allow the heap dump be generated in a single pass we remember the position 1785 // of the dump length and fix it up after all sub-records have been written. 1786 // To generate the sub-records we iterate over the heap, writing 1787 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP 1788 // records as we go. Once that is done we write records for some of the GC 1789 // roots. 1790 1791 void VM_HeapDumper::doit() { 1792 1793 HandleMark hm; 1794 CollectedHeap* ch = Universe::heap(); 1795 1796 ch->ensure_parsability(false); // must happen, even if collection does 1797 // not happen (e.g. due to GCLocker) 1798 1799 if (_gc_before_heap_dump) { 1800 if (GCLocker::is_active()) { 1801 warning("GC locker is held; pre-heapdump GC was skipped"); 1802 } else { 1803 ch->collect_as_vm_thread(GCCause::_heap_dump); 1804 } 1805 } 1806 1807 // At this point we should be the only dumper active, so 1808 // the following should be safe. 1809 set_global_dumper(); 1810 set_global_writer(); 1811 1812 // Write the file header - we always use 1.0.2 1813 size_t used = ch->used(); 1814 const char* header = "JAVA PROFILE 1.0.2"; 1815 1816 // header is few bytes long - no chance to overflow int 1817 writer()->write_raw((void*)header, (int)strlen(header)); 1818 writer()->write_u1(0); // terminator 1819 writer()->write_u4(oopSize); 1820 writer()->write_u8(os::javaTimeMillis()); 1821 1822 // HPROF_UTF8 records 1823 SymbolTableDumper sym_dumper(writer()); 1824 SymbolTable::symbols_do(&sym_dumper); 1825 1826 // write HPROF_LOAD_CLASS records 1827 { 1828 LockedClassesDo locked_load_classes(&do_load_class); 1829 ClassLoaderDataGraph::classes_do(&locked_load_classes); 1830 } 1831 Universe::basic_type_classes_do(&do_load_class); 1832 1833 // write HPROF_FRAME and HPROF_TRACE records 1834 // this must be called after _klass_map is built when iterating the classes above. 1835 dump_stack_traces(); 1836 1837 // write HPROF_HEAP_DUMP_SEGMENT 1838 DumperSupport::write_dump_header(writer()); 1839 1840 // Writes HPROF_GC_CLASS_DUMP records 1841 { 1842 LockedClassesDo locked_dump_class(&do_class_dump); 1843 ClassLoaderDataGraph::classes_do(&locked_dump_class); 1844 } 1845 Universe::basic_type_classes_do(&do_basic_type_array_class_dump); 1846 check_segment_length(); 1847 1848 // writes HPROF_GC_INSTANCE_DUMP records. 1849 // After each sub-record is written check_segment_length will be invoked 1850 // to check if the current segment exceeds a threshold. If so, a new 1851 // segment is started. 1852 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk 1853 // of the heap dump. 1854 HeapObjectDumper obj_dumper(this, writer()); 1855 Universe::heap()->safe_object_iterate(&obj_dumper); 1856 1857 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals 1858 do_threads(); 1859 check_segment_length(); 1860 1861 // HPROF_GC_ROOT_MONITOR_USED 1862 MonitorUsedDumper mon_dumper(writer()); 1863 ObjectSynchronizer::oops_do(&mon_dumper); 1864 check_segment_length(); 1865 1866 // HPROF_GC_ROOT_JNI_GLOBAL 1867 JNIGlobalsDumper jni_dumper(writer()); 1868 JNIHandles::oops_do(&jni_dumper); 1869 Universe::oops_do(&jni_dumper); // technically not jni roots, but global roots 1870 // for things like preallocated throwable backtraces 1871 check_segment_length(); 1872 1873 // HPROF_GC_ROOT_STICKY_CLASS 1874 // These should be classes in the NULL class loader data, and not all classes 1875 // if !ClassUnloading 1876 StickyClassDumper class_dumper(writer()); 1877 ClassLoaderData::the_null_class_loader_data()->classes_do(&class_dumper); 1878 1879 // fixes up the length of the dump record and writes the HPROF_HEAP_DUMP_END record. 1880 DumperSupport::end_of_dump(writer()); 1881 1882 // Now we clear the global variables, so that a future dumper might run. 1883 clear_global_dumper(); 1884 clear_global_writer(); 1885 } 1886 1887 void VM_HeapDumper::dump_stack_traces() { 1888 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites 1889 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4)); 1890 writer()->write_u4((u4) STACK_TRACE_ID); 1891 writer()->write_u4(0); // thread number 1892 writer()->write_u4(0); // frame count 1893 1894 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal); 1895 int frame_serial_num = 0; 1896 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) { 1897 oop threadObj = thread->threadObj(); 1898 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) { 1899 // dump thread stack trace 1900 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false); 1901 stack_trace->dump_stack_at_safepoint(-1); 1902 _stack_traces[_num_threads++] = stack_trace; 1903 1904 // write HPROF_FRAME records for this thread's stack trace 1905 int depth = stack_trace->get_stack_depth(); 1906 int thread_frame_start = frame_serial_num; 1907 int extra_frames = 0; 1908 // write fake frame that makes it look like the thread, which caused OOME, 1909 // is in the OutOfMemoryError zero-parameter constructor 1910 if (thread == _oome_thread && _oome_constructor != NULL) { 1911 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder()); 1912 // the class serial number starts from 1 1913 assert(oome_serial_num > 0, "OutOfMemoryError class not found"); 1914 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num, 1915 _oome_constructor, 0); 1916 extra_frames++; 1917 } 1918 for (int j=0; j < depth; j++) { 1919 StackFrameInfo* frame = stack_trace->stack_frame_at(j); 1920 Method* m = frame->method(); 1921 int class_serial_num = _klass_map->find(m->method_holder()); 1922 // the class serial number starts from 1 1923 assert(class_serial_num > 0, "class not found"); 1924 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci()); 1925 } 1926 depth += extra_frames; 1927 1928 // write HPROF_TRACE record for one thread 1929 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize); 1930 int stack_serial_num = _num_threads + STACK_TRACE_ID; 1931 writer()->write_u4(stack_serial_num); // stack trace serial number 1932 writer()->write_u4((u4) _num_threads); // thread serial number 1933 writer()->write_u4(depth); // frame count 1934 for (int j=1; j <= depth; j++) { 1935 writer()->write_id(thread_frame_start + j); 1936 } 1937 } 1938 } 1939 } 1940 1941 // dump the heap to given path. 1942 int HeapDumper::dump(const char* path) { 1943 assert(path != NULL && strlen(path) > 0, "path missing"); 1944 1945 // print message in interactive case 1946 if (print_to_tty()) { 1947 tty->print_cr("Dumping heap to %s ...", path); 1948 timer()->start(); 1949 } 1950 1951 // create the dump writer. If the file can be opened then bail 1952 DumpWriter writer(path); 1953 if (!writer.is_open()) { 1954 set_error(writer.error()); 1955 if (print_to_tty()) { 1956 tty->print_cr("Unable to create %s: %s", path, 1957 (error() != NULL) ? error() : "reason unknown"); 1958 } 1959 return -1; 1960 } 1961 1962 // generate the dump 1963 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome); 1964 if (Thread::current()->is_VM_thread()) { 1965 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint"); 1966 dumper.doit(); 1967 } else { 1968 VMThread::execute(&dumper); 1969 } 1970 1971 // close dump file and record any error that the writer may have encountered 1972 writer.close(); 1973 set_error(writer.error()); 1974 1975 // print message in interactive case 1976 if (print_to_tty()) { 1977 timer()->stop(); 1978 if (error() == NULL) { 1979 tty->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]", 1980 writer.bytes_written(), timer()->seconds()); 1981 } else { 1982 tty->print_cr("Dump file is incomplete: %s", writer.error()); 1983 } 1984 } 1985 1986 return (writer.error() == NULL) ? 0 : -1; 1987 } 1988 1989 // stop timer (if still active), and free any error string we might be holding 1990 HeapDumper::~HeapDumper() { 1991 if (timer()->is_active()) { 1992 timer()->stop(); 1993 } 1994 set_error(NULL); 1995 } 1996 1997 1998 // returns the error string (resource allocated), or NULL 1999 char* HeapDumper::error_as_C_string() const { 2000 if (error() != NULL) { 2001 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1); 2002 strcpy(str, error()); 2003 return str; 2004 } else { 2005 return NULL; 2006 } 2007 } 2008 2009 // set the error string 2010 void HeapDumper::set_error(char* error) { 2011 if (_error != NULL) { 2012 os::free(_error); 2013 } 2014 if (error == NULL) { 2015 _error = NULL; 2016 } else { 2017 _error = os::strdup(error); 2018 assert(_error != NULL, "allocation failure"); 2019 } 2020 } 2021 2022 // Called by out-of-memory error reporting by a single Java thread 2023 // outside of a JVM safepoint 2024 void HeapDumper::dump_heap_from_oome() { 2025 HeapDumper::dump_heap(true); 2026 } 2027 2028 // Called by error reporting by a single Java thread outside of a JVM safepoint, 2029 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various 2030 // callers are strictly serialized and guaranteed not to interfere below. For more 2031 // general use, however, this method will need modification to prevent 2032 // inteference when updating the static variables base_path and dump_file_seq below. 2033 void HeapDumper::dump_heap() { 2034 HeapDumper::dump_heap(false); 2035 } 2036 2037 void HeapDumper::dump_heap(bool oome) { 2038 static char base_path[JVM_MAXPATHLEN] = {'\0'}; 2039 static uint dump_file_seq = 0; 2040 char* my_path; 2041 const int max_digit_chars = 20; 2042 2043 const char* dump_file_name = "java_pid"; 2044 const char* dump_file_ext = ".hprof"; 2045 2046 // The dump file defaults to java_pid<pid>.hprof in the current working 2047 // directory. HeapDumpPath=<file> can be used to specify an alternative 2048 // dump file name or a directory where dump file is created. 2049 if (dump_file_seq == 0) { // first time in, we initialize base_path 2050 // Calculate potentially longest base path and check if we have enough 2051 // allocated statically. 2052 const size_t total_length = 2053 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) + 2054 strlen(os::file_separator()) + max_digit_chars + 2055 strlen(dump_file_name) + strlen(dump_file_ext) + 1; 2056 if (total_length > sizeof(base_path)) { 2057 warning("Cannot create heap dump file. HeapDumpPath is too long."); 2058 return; 2059 } 2060 2061 bool use_default_filename = true; 2062 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') { 2063 // HeapDumpPath=<file> not specified 2064 } else { 2065 strcpy(base_path, HeapDumpPath); 2066 // check if the path is a directory (must exist) 2067 DIR* dir = os::opendir(base_path); 2068 if (dir == NULL) { 2069 use_default_filename = false; 2070 } else { 2071 // HeapDumpPath specified a directory. We append a file separator 2072 // (if needed). 2073 os::closedir(dir); 2074 size_t fs_len = strlen(os::file_separator()); 2075 if (strlen(base_path) >= fs_len) { 2076 char* end = base_path; 2077 end += (strlen(base_path) - fs_len); 2078 if (strcmp(end, os::file_separator()) != 0) { 2079 strcat(base_path, os::file_separator()); 2080 } 2081 } 2082 } 2083 } 2084 // If HeapDumpPath wasn't a file name then we append the default name 2085 if (use_default_filename) { 2086 const size_t dlen = strlen(base_path); // if heap dump dir specified 2087 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s", 2088 dump_file_name, os::current_process_id(), dump_file_ext); 2089 } 2090 const size_t len = strlen(base_path) + 1; 2091 my_path = (char*)os::malloc(len, mtInternal); 2092 if (my_path == NULL) { 2093 warning("Cannot create heap dump file. Out of system memory."); 2094 return; 2095 } 2096 strncpy(my_path, base_path, len); 2097 } else { 2098 // Append a sequence number id for dumps following the first 2099 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0 2100 my_path = (char*)os::malloc(len, mtInternal); 2101 if (my_path == NULL) { 2102 warning("Cannot create heap dump file. Out of system memory."); 2103 return; 2104 } 2105 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq); 2106 } 2107 dump_file_seq++; // increment seq number for next time we dump 2108 2109 HeapDumper dumper(false /* no GC before heap dump */, 2110 true /* send to tty */, 2111 oome /* pass along out-of-memory-error flag */); 2112 dumper.dump(my_path); 2113 os::free(my_path); 2114 }