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