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