1 /* 2 * Copyright (c) 2005, 2011, 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_implementation/shared/vmGCOperations.hpp" 30 #include "memory/genCollectedHeap.hpp" 31 #include "memory/universe.hpp" 32 #include "oops/objArrayKlass.hpp" 33 #include "runtime/javaCalls.hpp" 34 #include "runtime/jniHandles.hpp" 35 #include "runtime/reflectionUtils.hpp" 36 #include "runtime/vframe.hpp" 37 #include "runtime/vmThread.hpp" 38 #include "runtime/vm_operations.hpp" 39 #include "services/heapDumper.hpp" 40 #include "services/threadService.hpp" 41 #include "utilities/ostream.hpp" 42 #ifndef SERIALGC 43 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" 44 #endif 45 46 /* 47 * HPROF binary format - description copied from: 48 * src/share/demo/jvmti/hprof/hprof_io.c 49 * 50 * 51 * header "JAVA PROFILE 1.0.1" or "JAVA PROFILE 1.0.2" 52 * (0-terminated) 53 * 54 * u4 size of identifiers. Identifiers are used to represent 55 * UTF8 strings, objects, stack traces, etc. They usually 56 * have the same size as host pointers. For example, on 57 * Solaris and Win32, the size is 4. 58 * u4 high word 59 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70 60 * [record]* a sequence of records. 61 * 62 * 63 * Record format: 64 * 65 * u1 a TAG denoting the type of the record 66 * u4 number of *microseconds* since the time stamp in the 67 * header. (wraps around in a little more than an hour) 68 * u4 number of bytes *remaining* in the record. Note that 69 * this number excludes the tag and the length field itself. 70 * [u1]* BODY of the record (a sequence of bytes) 71 * 72 * 73 * The following TAGs are supported: 74 * 75 * TAG BODY notes 76 *---------------------------------------------------------- 77 * HPROF_UTF8 a UTF8-encoded name 78 * 79 * id name ID 80 * [u1]* UTF8 characters (no trailing zero) 81 * 82 * HPROF_LOAD_CLASS a newly loaded class 83 * 84 * u4 class serial number (> 0) 85 * id class object ID 86 * u4 stack trace serial number 87 * id class name ID 88 * 89 * HPROF_UNLOAD_CLASS an unloading class 90 * 91 * u4 class serial_number 92 * 93 * HPROF_FRAME a Java stack frame 94 * 95 * id stack frame ID 96 * id method name ID 97 * id method signature ID 98 * id source file name ID 99 * u4 class serial number 100 * i4 line number. >0: normal 101 * -1: unknown 102 * -2: compiled method 103 * -3: native method 104 * 105 * HPROF_TRACE a Java stack trace 106 * 107 * u4 stack trace serial number 108 * u4 thread serial number 109 * u4 number of frames 110 * [id]* stack frame IDs 111 * 112 * 113 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC 114 * 115 * u2 flags 0x0001: incremental vs. complete 116 * 0x0002: sorted by allocation vs. live 117 * 0x0004: whether to force a GC 118 * u4 cutoff ratio 119 * u4 total live bytes 120 * u4 total live instances 121 * u8 total bytes allocated 122 * u8 total instances allocated 123 * u4 number of sites that follow 124 * [u1 is_array: 0: normal object 125 * 2: object array 126 * 4: boolean array 127 * 5: char array 128 * 6: float array 129 * 7: double array 130 * 8: byte array 131 * 9: short array 132 * 10: int array 133 * 11: long array 134 * u4 class serial number (may be zero during startup) 135 * u4 stack trace serial number 136 * u4 number of bytes alive 137 * u4 number of instances alive 138 * u4 number of bytes allocated 139 * u4]* number of instance allocated 140 * 141 * HPROF_START_THREAD a newly started thread. 142 * 143 * u4 thread serial number (> 0) 144 * id thread object ID 145 * u4 stack trace serial number 146 * id thread name ID 147 * id thread group name ID 148 * id thread group parent name ID 149 * 150 * HPROF_END_THREAD a terminating thread. 151 * 152 * u4 thread serial number 153 * 154 * HPROF_HEAP_SUMMARY heap summary 155 * 156 * u4 total live bytes 157 * u4 total live instances 158 * u8 total bytes allocated 159 * u8 total instances allocated 160 * 161 * HPROF_HEAP_DUMP denote a heap dump 162 * 163 * [heap dump sub-records]* 164 * 165 * There are four kinds of heap dump sub-records: 166 * 167 * u1 sub-record type 168 * 169 * HPROF_GC_ROOT_UNKNOWN unknown root 170 * 171 * id object ID 172 * 173 * HPROF_GC_ROOT_THREAD_OBJ thread object 174 * 175 * id thread object ID (may be 0 for a 176 * thread newly attached through JNI) 177 * u4 thread sequence number 178 * u4 stack trace sequence number 179 * 180 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root 181 * 182 * id object ID 183 * id JNI global ref ID 184 * 185 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref 186 * 187 * id object ID 188 * u4 thread serial number 189 * u4 frame # in stack trace (-1 for empty) 190 * 191 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame 192 * 193 * id object ID 194 * u4 thread serial number 195 * u4 frame # in stack trace (-1 for empty) 196 * 197 * HPROF_GC_ROOT_NATIVE_STACK Native stack 198 * 199 * id object ID 200 * u4 thread serial number 201 * 202 * HPROF_GC_ROOT_STICKY_CLASS System class 203 * 204 * id object ID 205 * 206 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block 207 * 208 * id object ID 209 * u4 thread serial number 210 * 211 * HPROF_GC_ROOT_MONITOR_USED Busy monitor 212 * 213 * id object ID 214 * 215 * HPROF_GC_CLASS_DUMP dump of a class object 216 * 217 * id class object ID 218 * u4 stack trace serial number 219 * id super class object ID 220 * id class loader object ID 221 * id signers object ID 222 * id protection domain object ID 223 * id reserved 224 * id reserved 225 * 226 * u4 instance size (in bytes) 227 * 228 * u2 size of constant pool 229 * [u2, constant pool index, 230 * ty, type 231 * 2: object 232 * 4: boolean 233 * 5: char 234 * 6: float 235 * 7: double 236 * 8: byte 237 * 9: short 238 * 10: int 239 * 11: long 240 * vl]* and value 241 * 242 * u2 number of static fields 243 * [id, static field name, 244 * ty, type, 245 * vl]* and value 246 * 247 * u2 number of inst. fields (not inc. super) 248 * [id, instance field name, 249 * ty]* type 250 * 251 * HPROF_GC_INSTANCE_DUMP dump of a normal object 252 * 253 * id object ID 254 * u4 stack trace serial number 255 * id class object ID 256 * u4 number of bytes that follow 257 * [vl]* instance field values (class, followed 258 * by super, super's super ...) 259 * 260 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array 261 * 262 * id array object ID 263 * u4 stack trace serial number 264 * u4 number of elements 265 * id array class ID 266 * [id]* elements 267 * 268 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array 269 * 270 * id array object ID 271 * u4 stack trace serial number 272 * u4 number of elements 273 * u1 element type 274 * 4: boolean array 275 * 5: char array 276 * 6: float array 277 * 7: double array 278 * 8: byte array 279 * 9: short array 280 * 10: int array 281 * 11: long array 282 * [u1]* elements 283 * 284 * HPROF_CPU_SAMPLES a set of sample traces of running threads 285 * 286 * u4 total number of samples 287 * u4 # of traces 288 * [u4 # of samples 289 * u4]* stack trace serial number 290 * 291 * HPROF_CONTROL_SETTINGS the settings of on/off switches 292 * 293 * u4 0x00000001: alloc traces on/off 294 * 0x00000002: cpu sampling on/off 295 * u2 stack trace depth 296 * 297 * 298 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally 299 * be generated as a sequence of heap dump segments. This sequence is 300 * terminated by an end record. The additional tags allowed by format 301 * "JAVA PROFILE 1.0.2" are: 302 * 303 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment 304 * 305 * [heap dump sub-records]* 306 * The same sub-record types allowed by HPROF_HEAP_DUMP 307 * 308 * HPROF_HEAP_DUMP_END denotes the end of a heap dump 309 * 310 */ 311 312 313 // HPROF tags 314 315 typedef enum { 316 // top-level records 317 HPROF_UTF8 = 0x01, 318 HPROF_LOAD_CLASS = 0x02, 319 HPROF_UNLOAD_CLASS = 0x03, 320 HPROF_FRAME = 0x04, 321 HPROF_TRACE = 0x05, 322 HPROF_ALLOC_SITES = 0x06, 323 HPROF_HEAP_SUMMARY = 0x07, 324 HPROF_START_THREAD = 0x0A, 325 HPROF_END_THREAD = 0x0B, 326 HPROF_HEAP_DUMP = 0x0C, 327 HPROF_CPU_SAMPLES = 0x0D, 328 HPROF_CONTROL_SETTINGS = 0x0E, 329 330 // 1.0.2 record types 331 HPROF_HEAP_DUMP_SEGMENT = 0x1C, 332 HPROF_HEAP_DUMP_END = 0x2C, 333 334 // field types 335 HPROF_ARRAY_OBJECT = 0x01, 336 HPROF_NORMAL_OBJECT = 0x02, 337 HPROF_BOOLEAN = 0x04, 338 HPROF_CHAR = 0x05, 339 HPROF_FLOAT = 0x06, 340 HPROF_DOUBLE = 0x07, 341 HPROF_BYTE = 0x08, 342 HPROF_SHORT = 0x09, 343 HPROF_INT = 0x0A, 344 HPROF_LONG = 0x0B, 345 346 // data-dump sub-records 347 HPROF_GC_ROOT_UNKNOWN = 0xFF, 348 HPROF_GC_ROOT_JNI_GLOBAL = 0x01, 349 HPROF_GC_ROOT_JNI_LOCAL = 0x02, 350 HPROF_GC_ROOT_JAVA_FRAME = 0x03, 351 HPROF_GC_ROOT_NATIVE_STACK = 0x04, 352 HPROF_GC_ROOT_STICKY_CLASS = 0x05, 353 HPROF_GC_ROOT_THREAD_BLOCK = 0x06, 354 HPROF_GC_ROOT_MONITOR_USED = 0x07, 355 HPROF_GC_ROOT_THREAD_OBJ = 0x08, 356 HPROF_GC_CLASS_DUMP = 0x20, 357 HPROF_GC_INSTANCE_DUMP = 0x21, 358 HPROF_GC_OBJ_ARRAY_DUMP = 0x22, 359 HPROF_GC_PRIM_ARRAY_DUMP = 0x23 360 } hprofTag; 361 362 // Default stack trace ID (used for dummy HPROF_TRACE record) 363 enum { 364 STACK_TRACE_ID = 1, 365 INITIAL_CLASS_COUNT = 200 366 }; 367 368 // Supports I/O operations on a dump file 369 370 class DumpWriter : public StackObj { 371 private: 372 enum { 373 io_buffer_size = 8*M 374 }; 375 376 int _fd; // file descriptor (-1 if dump file not open) 377 jlong _bytes_written; // number of byte written to dump file 378 379 char* _buffer; // internal buffer 380 int _size; 381 int _pos; 382 383 char* _error; // error message when I/O fails 384 385 void set_file_descriptor(int fd) { _fd = fd; } 386 int file_descriptor() const { return _fd; } 387 388 char* buffer() const { return _buffer; } 389 int buffer_size() const { return _size; } 390 int position() const { return _pos; } 391 void set_position(int pos) { _pos = pos; } 392 393 void set_error(const char* error) { _error = (char*)os::strdup(error); } 394 395 // all I/O go through this function 396 void write_internal(void* s, int len); 397 398 public: 399 DumpWriter(const char* path); 400 ~DumpWriter(); 401 402 void close(); 403 bool is_open() const { return file_descriptor() >= 0; } 404 void flush(); 405 406 // total number of bytes written to the disk 407 jlong bytes_written() const { return _bytes_written; } 408 409 // adjust the number of bytes written to disk (used to keep the count 410 // of the number of bytes written in case of rewrites) 411 void adjust_bytes_written(jlong n) { _bytes_written += n; } 412 413 // number of (buffered) bytes as yet unwritten to the dump file 414 jlong bytes_unwritten() const { return (jlong)position(); } 415 416 char* error() const { return _error; } 417 418 jlong current_offset(); 419 void seek_to_offset(jlong pos); 420 421 // writer functions 422 void write_raw(void* s, int len); 423 void write_u1(u1 x) { write_raw((void*)&x, 1); } 424 void write_u2(u2 x); 425 void write_u4(u4 x); 426 void write_u8(u8 x); 427 void write_objectID(oop o); 428 void write_classID(Klass* k); 429 void write_id(u4 x); 430 }; 431 432 DumpWriter::DumpWriter(const char* path) { 433 // try to allocate an I/O buffer of io_buffer_size. If there isn't 434 // sufficient memory then reduce size until we can allocate something. 435 _size = io_buffer_size; 436 do { 437 _buffer = (char*)os::malloc(_size); 438 if (_buffer == NULL) { 439 _size = _size >> 1; 440 } 441 } while (_buffer == NULL && _size > 0); 442 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check"); 443 _pos = 0; 444 _error = NULL; 445 _bytes_written = 0L; 446 _fd = os::create_binary_file(path, false); // don't replace existing file 447 448 // if the open failed we record the error 449 if (_fd < 0) { 450 _error = (char*)os::strdup(strerror(errno)); 451 } 452 } 453 454 DumpWriter::~DumpWriter() { 455 // flush and close dump file 456 if (is_open()) { 457 close(); 458 } 459 if (_buffer != NULL) os::free(_buffer); 460 if (_error != NULL) os::free(_error); 461 } 462 463 // closes dump file (if open) 464 void DumpWriter::close() { 465 // flush and close dump file 466 if (is_open()) { 467 flush(); 468 ::close(file_descriptor()); 469 set_file_descriptor(-1); 470 } 471 } 472 473 // write directly to the file 474 void DumpWriter::write_internal(void* s, int len) { 475 if (is_open()) { 476 int n = ::write(file_descriptor(), s, len); 477 if (n > 0) { 478 _bytes_written += n; 479 } 480 if (n != len) { 481 if (n < 0) { 482 set_error(strerror(errno)); 483 } else { 484 set_error("file size limit"); 485 } 486 ::close(file_descriptor()); 487 set_file_descriptor(-1); 488 } 489 } 490 } 491 492 // write raw bytes 493 void DumpWriter::write_raw(void* s, int len) { 494 if (is_open()) { 495 // flush buffer to make toom 496 if ((position()+ len) >= buffer_size()) { 497 flush(); 498 } 499 500 // buffer not available or too big to buffer it 501 if ((buffer() == NULL) || (len >= buffer_size())) { 502 write_internal(s, len); 503 } else { 504 // Should optimize this for u1/u2/u4/u8 sizes. 505 memcpy(buffer() + position(), s, len); 506 set_position(position() + len); 507 } 508 } 509 } 510 511 // flush any buffered bytes to the file 512 void DumpWriter::flush() { 513 if (is_open() && position() > 0) { 514 write_internal(buffer(), position()); 515 set_position(0); 516 } 517 } 518 519 520 jlong DumpWriter::current_offset() { 521 if (is_open()) { 522 // the offset is the file offset plus whatever we have buffered 523 jlong offset = os::current_file_offset(file_descriptor()); 524 assert(offset >= 0, "lseek failed"); 525 return offset + (jlong)position(); 526 } else { 527 return (jlong)-1; 528 } 529 } 530 531 void DumpWriter::seek_to_offset(jlong off) { 532 assert(off >= 0, "bad offset"); 533 534 // need to flush before seeking 535 flush(); 536 537 // may be closed due to I/O error 538 if (is_open()) { 539 jlong n = os::seek_to_file_offset(file_descriptor(), off); 540 assert(n >= 0, "lseek failed"); 541 } 542 } 543 544 void DumpWriter::write_u2(u2 x) { 545 u2 v; 546 Bytes::put_Java_u2((address)&v, x); 547 write_raw((void*)&v, 2); 548 } 549 550 void DumpWriter::write_u4(u4 x) { 551 u4 v; 552 Bytes::put_Java_u4((address)&v, x); 553 write_raw((void*)&v, 4); 554 } 555 556 void DumpWriter::write_u8(u8 x) { 557 u8 v; 558 Bytes::put_Java_u8((address)&v, x); 559 write_raw((void*)&v, 8); 560 } 561 562 void DumpWriter::write_objectID(oop o) { 563 address a = (address)((uintptr_t)o); 564 #ifdef _LP64 565 write_u8((u8)a); 566 #else 567 write_u4((u4)a); 568 #endif 569 } 570 571 void DumpWriter::write_id(u4 x) { 572 #ifdef _LP64 573 write_u8((u8) x); 574 #else 575 write_u4(x); 576 #endif 577 } 578 579 // We use java mirror as the class ID 580 void DumpWriter::write_classID(Klass* k) { 581 write_objectID(k->java_mirror()); 582 } 583 584 585 586 // Support class with a collection of functions used when dumping the heap 587 588 class DumperSupport : AllStatic { 589 public: 590 591 // write a header of the given type 592 static void write_header(DumpWriter* writer, hprofTag tag, u4 len); 593 594 // returns hprof tag for the given type signature 595 static hprofTag sig2tag(symbolOop sig); 596 // returns hprof tag for the given basic type 597 static hprofTag type2tag(BasicType type); 598 599 // returns the size of the instance of the given class 600 static u4 instance_size(klassOop k); 601 602 // dump a jfloat 603 static void dump_float(DumpWriter* writer, jfloat f); 604 // dump a jdouble 605 static void dump_double(DumpWriter* writer, jdouble d); 606 // dumps the raw value of the given field 607 static void dump_field_value(DumpWriter* writer, char type, address addr); 608 // dumps static fields of the given class 609 static void dump_static_fields(DumpWriter* writer, klassOop k); 610 // dump the raw values of the instance fields of the given object 611 static void dump_instance_fields(DumpWriter* writer, oop o); 612 // dumps the definition of the instance fields for a given class 613 static void dump_instance_field_descriptors(DumpWriter* writer, klassOop k); 614 // creates HPROF_GC_INSTANCE_DUMP record for the given object 615 static void dump_instance(DumpWriter* writer, oop o); 616 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its 617 // array classes 618 static void dump_class_and_array_classes(DumpWriter* writer, klassOop k); 619 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 620 // class (and each multi-dimensional array class too) 621 static void dump_basic_type_array_class(DumpWriter* writer, klassOop k); 622 623 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 624 static void dump_object_array(DumpWriter* writer, objArrayOop array); 625 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 626 static void dump_prim_array(DumpWriter* writer, typeArrayOop array); 627 // create HPROF_FRAME record for the given method and bci 628 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, methodOop m, int bci); 629 }; 630 631 // write a header of the given type 632 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) { 633 writer->write_u1((u1)tag); 634 writer->write_u4(0); // current ticks 635 writer->write_u4(len); 636 } 637 638 // returns hprof tag for the given type signature 639 hprofTag DumperSupport::sig2tag(symbolOop sig) { 640 switch (sig->byte_at(0)) { 641 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT; 642 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT; 643 case JVM_SIGNATURE_BYTE : return HPROF_BYTE; 644 case JVM_SIGNATURE_CHAR : return HPROF_CHAR; 645 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT; 646 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE; 647 case JVM_SIGNATURE_INT : return HPROF_INT; 648 case JVM_SIGNATURE_LONG : return HPROF_LONG; 649 case JVM_SIGNATURE_SHORT : return HPROF_SHORT; 650 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN; 651 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 652 } 653 } 654 655 hprofTag DumperSupport::type2tag(BasicType type) { 656 switch (type) { 657 case T_BYTE : return HPROF_BYTE; 658 case T_CHAR : return HPROF_CHAR; 659 case T_FLOAT : return HPROF_FLOAT; 660 case T_DOUBLE : return HPROF_DOUBLE; 661 case T_INT : return HPROF_INT; 662 case T_LONG : return HPROF_LONG; 663 case T_SHORT : return HPROF_SHORT; 664 case T_BOOLEAN : return HPROF_BOOLEAN; 665 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 666 } 667 } 668 669 // dump a jfloat 670 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) { 671 if (g_isnan(f)) { 672 writer->write_u4(0x7fc00000); // collapsing NaNs 673 } else { 674 union { 675 int i; 676 float f; 677 } u; 678 u.f = (float)f; 679 writer->write_u4((u4)u.i); 680 } 681 } 682 683 // dump a jdouble 684 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) { 685 union { 686 jlong l; 687 double d; 688 } u; 689 if (g_isnan(d)) { // collapsing NaNs 690 u.l = (jlong)(0x7ff80000); 691 u.l = (u.l << 32); 692 } else { 693 u.d = (double)d; 694 } 695 writer->write_u8((u8)u.l); 696 } 697 698 // dumps the raw value of the given field 699 void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) { 700 switch (type) { 701 case JVM_SIGNATURE_CLASS : 702 case JVM_SIGNATURE_ARRAY : { 703 oop o; 704 if (UseCompressedOops) { 705 o = oopDesc::load_decode_heap_oop((narrowOop*)addr); 706 } else { 707 o = oopDesc::load_decode_heap_oop((oop*)addr); 708 } 709 710 // reflection and sun.misc.Unsafe classes may have a reference to a 711 // klassOop so filter it out. 712 if (o != NULL && o->is_klass()) { 713 o = NULL; 714 } 715 716 // FIXME: When sharing is enabled we don't emit field references to objects 717 // in shared spaces. We can remove this once we write records for the classes 718 // and strings that are shared. 719 if (o != NULL && o->is_shared()) { 720 o = NULL; 721 } 722 writer->write_objectID(o); 723 break; 724 } 725 case JVM_SIGNATURE_BYTE : { 726 jbyte* b = (jbyte*)addr; 727 writer->write_u1((u1)*b); 728 break; 729 } 730 case JVM_SIGNATURE_CHAR : { 731 jchar* c = (jchar*)addr; 732 writer->write_u2((u2)*c); 733 break; 734 } 735 case JVM_SIGNATURE_SHORT : { 736 jshort* s = (jshort*)addr; 737 writer->write_u2((u2)*s); 738 break; 739 } 740 case JVM_SIGNATURE_FLOAT : { 741 jfloat* f = (jfloat*)addr; 742 dump_float(writer, *f); 743 break; 744 } 745 case JVM_SIGNATURE_DOUBLE : { 746 jdouble* f = (jdouble*)addr; 747 dump_double(writer, *f); 748 break; 749 } 750 case JVM_SIGNATURE_INT : { 751 jint* i = (jint*)addr; 752 writer->write_u4((u4)*i); 753 break; 754 } 755 case JVM_SIGNATURE_LONG : { 756 jlong* l = (jlong*)addr; 757 writer->write_u8((u8)*l); 758 break; 759 } 760 case JVM_SIGNATURE_BOOLEAN : { 761 jboolean* b = (jboolean*)addr; 762 writer->write_u1((u1)*b); 763 break; 764 } 765 default : ShouldNotReachHere(); 766 } 767 } 768 769 // returns the size of the instance of the given class 770 u4 DumperSupport::instance_size(klassOop k) { 771 HandleMark hm; 772 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 773 774 int size = 0; 775 776 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { 777 if (!fld.access_flags().is_static()) { 778 symbolOop sig = fld.signature(); 779 switch (sig->byte_at(0)) { 780 case JVM_SIGNATURE_CLASS : 781 case JVM_SIGNATURE_ARRAY : size += oopSize; break; 782 783 case JVM_SIGNATURE_BYTE : 784 case JVM_SIGNATURE_BOOLEAN : size += 1; break; 785 786 case JVM_SIGNATURE_CHAR : 787 case JVM_SIGNATURE_SHORT : size += 2; break; 788 789 case JVM_SIGNATURE_INT : 790 case JVM_SIGNATURE_FLOAT : size += 4; break; 791 792 case JVM_SIGNATURE_LONG : 793 case JVM_SIGNATURE_DOUBLE : size += 8; break; 794 795 default : ShouldNotReachHere(); 796 } 797 } 798 } 799 return (u4)size; 800 } 801 802 // dumps static fields of the given class 803 void DumperSupport::dump_static_fields(DumpWriter* writer, klassOop k) { 804 HandleMark hm; 805 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 806 807 // pass 1 - count the static fields 808 u2 field_count = 0; 809 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { 810 if (fldc.access_flags().is_static()) field_count++; 811 } 812 813 writer->write_u2(field_count); 814 815 // pass 2 - dump the field descriptors and raw values 816 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { 817 if (fld.access_flags().is_static()) { 818 symbolOop sig = fld.signature(); 819 820 writer->write_objectID(fld.name()); // name 821 writer->write_u1(sig2tag(sig)); // type 822 823 // value 824 int offset = fld.offset(); 825 address addr = (address)k + offset; 826 827 dump_field_value(writer, sig->byte_at(0), addr); 828 } 829 } 830 } 831 832 // dump the raw values of the instance fields of the given object 833 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) { 834 HandleMark hm; 835 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass()); 836 837 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { 838 if (!fld.access_flags().is_static()) { 839 symbolOop sig = fld.signature(); 840 address addr = (address)o + fld.offset(); 841 842 dump_field_value(writer, sig->byte_at(0), addr); 843 } 844 } 845 } 846 847 // dumps the definition of the instance fields for a given class 848 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, klassOop k) { 849 HandleMark hm; 850 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 851 852 // pass 1 - count the instance fields 853 u2 field_count = 0; 854 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { 855 if (!fldc.access_flags().is_static()) field_count++; 856 } 857 858 writer->write_u2(field_count); 859 860 // pass 2 - dump the field descriptors 861 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { 862 if (!fld.access_flags().is_static()) { 863 symbolOop sig = fld.signature(); 864 865 writer->write_objectID(fld.name()); // name 866 writer->write_u1(sig2tag(sig)); // type 867 } 868 } 869 } 870 871 // creates HPROF_GC_INSTANCE_DUMP record for the given object 872 void DumperSupport::dump_instance(DumpWriter* writer, oop o) { 873 klassOop k = o->klass(); 874 875 writer->write_u1(HPROF_GC_INSTANCE_DUMP); 876 writer->write_objectID(o); 877 writer->write_u4(STACK_TRACE_ID); 878 879 // class ID 880 writer->write_classID(Klass::cast(k)); 881 882 // number of bytes that follow 883 writer->write_u4(instance_size(k) ); 884 885 // field values 886 dump_instance_fields(writer, o); 887 } 888 889 // creates HPROF_GC_CLASS_DUMP record for the given class and each of 890 // its array classes 891 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, klassOop k) { 892 Klass* klass = Klass::cast(k); 893 assert(klass->oop_is_instance(), "not an instanceKlass"); 894 instanceKlass* ik = (instanceKlass*)klass; 895 896 writer->write_u1(HPROF_GC_CLASS_DUMP); 897 898 // class ID 899 writer->write_classID(ik); 900 writer->write_u4(STACK_TRACE_ID); 901 902 // super class ID 903 klassOop java_super = ik->java_super(); 904 if (java_super == NULL) { 905 writer->write_objectID(NULL); 906 } else { 907 writer->write_classID(Klass::cast(java_super)); 908 } 909 910 writer->write_objectID(ik->class_loader()); 911 writer->write_objectID(ik->signers()); 912 writer->write_objectID(ik->protection_domain()); 913 914 // reserved 915 writer->write_objectID(NULL); 916 writer->write_objectID(NULL); 917 918 // instance size 919 writer->write_u4(DumperSupport::instance_size(k)); 920 921 // size of constant pool - ignored by HAT 1.1 922 writer->write_u2(0); 923 924 // number of static fields 925 dump_static_fields(writer, k); 926 927 // description of instance fields 928 dump_instance_field_descriptors(writer, k); 929 930 // array classes 931 k = klass->array_klass_or_null(); 932 while (k != NULL) { 933 Klass* klass = Klass::cast(k); 934 assert(klass->oop_is_objArray(), "not an objArrayKlass"); 935 936 writer->write_u1(HPROF_GC_CLASS_DUMP); 937 writer->write_classID(klass); 938 writer->write_u4(STACK_TRACE_ID); 939 940 // super class of array classes is java.lang.Object 941 java_super = klass->java_super(); 942 assert(java_super != NULL, "checking"); 943 writer->write_classID(Klass::cast(java_super)); 944 945 writer->write_objectID(ik->class_loader()); 946 writer->write_objectID(ik->signers()); 947 writer->write_objectID(ik->protection_domain()); 948 949 writer->write_objectID(NULL); // reserved 950 writer->write_objectID(NULL); 951 writer->write_u4(0); // instance size 952 writer->write_u2(0); // constant pool 953 writer->write_u2(0); // static fields 954 writer->write_u2(0); // instance fields 955 956 // get the array class for the next rank 957 k = klass->array_klass_or_null(); 958 } 959 } 960 961 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 962 // class (and each multi-dimensional array class too) 963 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, klassOop k) { 964 // array classes 965 while (k != NULL) { 966 Klass* klass = Klass::cast(k); 967 968 writer->write_u1(HPROF_GC_CLASS_DUMP); 969 writer->write_classID(klass); 970 writer->write_u4(STACK_TRACE_ID); 971 972 // super class of array classes is java.lang.Object 973 klassOop java_super = klass->java_super(); 974 assert(java_super != NULL, "checking"); 975 writer->write_classID(Klass::cast(java_super)); 976 977 writer->write_objectID(NULL); // loader 978 writer->write_objectID(NULL); // signers 979 writer->write_objectID(NULL); // protection domain 980 981 writer->write_objectID(NULL); // reserved 982 writer->write_objectID(NULL); 983 writer->write_u4(0); // instance size 984 writer->write_u2(0); // constant pool 985 writer->write_u2(0); // static fields 986 writer->write_u2(0); // instance fields 987 988 // get the array class for the next rank 989 k = klass->array_klass_or_null(); 990 } 991 } 992 993 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 994 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) { 995 996 // filter this 997 if (array->klass() == Universe::systemObjArrayKlassObj()) return; 998 999 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP); 1000 writer->write_objectID(array); 1001 writer->write_u4(STACK_TRACE_ID); 1002 writer->write_u4((u4)array->length()); 1003 1004 // array class ID 1005 writer->write_classID(Klass::cast(array->klass())); 1006 1007 // [id]* elements 1008 for (int index=0; index<array->length(); index++) { 1009 oop o = array->obj_at(index); 1010 writer->write_objectID(o); 1011 } 1012 } 1013 1014 #define WRITE_ARRAY(Array, Type, Size) \ 1015 for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); } 1016 1017 1018 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 1019 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) { 1020 BasicType type = typeArrayKlass::cast(array->klass())->element_type(); 1021 1022 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP); 1023 writer->write_objectID(array); 1024 writer->write_u4(STACK_TRACE_ID); 1025 writer->write_u4((u4)array->length()); 1026 writer->write_u1(type2tag(type)); 1027 1028 // nothing to copy 1029 if (array->length() == 0) { 1030 return; 1031 } 1032 1033 // If the byte ordering is big endian then we can copy most types directly 1034 int length_in_bytes = array->length() * type2aelembytes(type); 1035 assert(length_in_bytes > 0, "nothing to copy"); 1036 1037 switch (type) { 1038 case T_INT : { 1039 if (Bytes::is_Java_byte_ordering_different()) { 1040 WRITE_ARRAY(array, int, u4); 1041 } else { 1042 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes); 1043 } 1044 break; 1045 } 1046 case T_BYTE : { 1047 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes); 1048 break; 1049 } 1050 case T_CHAR : { 1051 if (Bytes::is_Java_byte_ordering_different()) { 1052 WRITE_ARRAY(array, char, u2); 1053 } else { 1054 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes); 1055 } 1056 break; 1057 } 1058 case T_SHORT : { 1059 if (Bytes::is_Java_byte_ordering_different()) { 1060 WRITE_ARRAY(array, short, u2); 1061 } else { 1062 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes); 1063 } 1064 break; 1065 } 1066 case T_BOOLEAN : { 1067 if (Bytes::is_Java_byte_ordering_different()) { 1068 WRITE_ARRAY(array, bool, u1); 1069 } else { 1070 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes); 1071 } 1072 break; 1073 } 1074 case T_LONG : { 1075 if (Bytes::is_Java_byte_ordering_different()) { 1076 WRITE_ARRAY(array, long, u8); 1077 } else { 1078 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes); 1079 } 1080 break; 1081 } 1082 1083 // handle float/doubles in a special value to ensure than NaNs are 1084 // written correctly. TO DO: Check if we can avoid this on processors that 1085 // use IEEE 754. 1086 1087 case T_FLOAT : { 1088 for (int i=0; i<array->length(); i++) { 1089 dump_float( writer, array->float_at(i) ); 1090 } 1091 break; 1092 } 1093 case T_DOUBLE : { 1094 for (int i=0; i<array->length(); i++) { 1095 dump_double( writer, array->double_at(i) ); 1096 } 1097 break; 1098 } 1099 default : ShouldNotReachHere(); 1100 } 1101 } 1102 1103 // create a HPROF_FRAME record of the given methodOop and bci 1104 void DumperSupport::dump_stack_frame(DumpWriter* writer, 1105 int frame_serial_num, 1106 int class_serial_num, 1107 methodOop m, 1108 int bci) { 1109 int line_number; 1110 if (m->is_native()) { 1111 line_number = -3; // native frame 1112 } else { 1113 line_number = m->line_number_from_bci(bci); 1114 } 1115 1116 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4)); 1117 writer->write_id(frame_serial_num); // frame serial number 1118 writer->write_objectID(m->name()); // method's name 1119 writer->write_objectID(m->signature()); // method's signature 1120 1121 assert(Klass::cast(m->method_holder())->oop_is_instance(), "not instanceKlass"); 1122 writer->write_objectID(instanceKlass::cast(m->method_holder())->source_file_name()); // source file name 1123 writer->write_u4(class_serial_num); // class serial number 1124 writer->write_u4((u4) line_number); // line number 1125 } 1126 1127 // Support class used to generate HPROF_UTF8 records from the entries in the 1128 // SymbolTable. 1129 1130 class SymbolTableDumper : public OopClosure { 1131 private: 1132 DumpWriter* _writer; 1133 DumpWriter* writer() const { return _writer; } 1134 public: 1135 SymbolTableDumper(DumpWriter* writer) { _writer = writer; } 1136 void do_oop(oop* obj_p); 1137 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1138 }; 1139 1140 void SymbolTableDumper::do_oop(oop* obj_p) { 1141 ResourceMark rm; 1142 symbolOop sym = (symbolOop)*obj_p; 1143 1144 int len = sym->utf8_length(); 1145 if (len > 0) { 1146 char* s = sym->as_utf8(); 1147 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len); 1148 writer()->write_objectID(sym); 1149 writer()->write_raw(s, len); 1150 } 1151 } 1152 1153 1154 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records 1155 1156 class JNILocalsDumper : public OopClosure { 1157 private: 1158 DumpWriter* _writer; 1159 u4 _thread_serial_num; 1160 int _frame_num; 1161 DumpWriter* writer() const { return _writer; } 1162 public: 1163 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) { 1164 _writer = writer; 1165 _thread_serial_num = thread_serial_num; 1166 _frame_num = -1; // default - empty stack 1167 } 1168 void set_frame_number(int n) { _frame_num = n; } 1169 void do_oop(oop* obj_p); 1170 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1171 }; 1172 1173 1174 void JNILocalsDumper::do_oop(oop* obj_p) { 1175 // ignore null or deleted handles 1176 oop o = *obj_p; 1177 if (o != NULL && o != JNIHandles::deleted_handle()) { 1178 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL); 1179 writer()->write_objectID(o); 1180 writer()->write_u4(_thread_serial_num); 1181 writer()->write_u4((u4)_frame_num); 1182 } 1183 } 1184 1185 1186 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records 1187 1188 class JNIGlobalsDumper : public OopClosure { 1189 private: 1190 DumpWriter* _writer; 1191 DumpWriter* writer() const { return _writer; } 1192 1193 public: 1194 JNIGlobalsDumper(DumpWriter* writer) { 1195 _writer = writer; 1196 } 1197 void do_oop(oop* obj_p); 1198 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1199 }; 1200 1201 void JNIGlobalsDumper::do_oop(oop* obj_p) { 1202 oop o = *obj_p; 1203 1204 // ignore these 1205 if (o == NULL || o == JNIHandles::deleted_handle()) return; 1206 1207 // we ignore global ref to symbols and other internal objects 1208 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) { 1209 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL); 1210 writer()->write_objectID(o); 1211 writer()->write_objectID((oopDesc*)obj_p); // global ref ID 1212 } 1213 }; 1214 1215 1216 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records 1217 1218 class MonitorUsedDumper : public OopClosure { 1219 private: 1220 DumpWriter* _writer; 1221 DumpWriter* writer() const { return _writer; } 1222 public: 1223 MonitorUsedDumper(DumpWriter* writer) { 1224 _writer = writer; 1225 } 1226 void do_oop(oop* obj_p) { 1227 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED); 1228 writer()->write_objectID(*obj_p); 1229 } 1230 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1231 }; 1232 1233 1234 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records 1235 1236 class StickyClassDumper : public OopClosure { 1237 private: 1238 DumpWriter* _writer; 1239 DumpWriter* writer() const { return _writer; } 1240 public: 1241 StickyClassDumper(DumpWriter* writer) { 1242 _writer = writer; 1243 } 1244 void do_oop(oop* obj_p); 1245 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1246 }; 1247 1248 void StickyClassDumper::do_oop(oop* obj_p) { 1249 if (*obj_p != NULL) { 1250 oop o = *obj_p; 1251 if (o->is_klass()) { 1252 klassOop k = klassOop(o); 1253 if (Klass::cast(k)->oop_is_instance()) { 1254 instanceKlass* ik = instanceKlass::cast(k); 1255 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS); 1256 writer()->write_classID(ik); 1257 } 1258 } 1259 } 1260 } 1261 1262 1263 class VM_HeapDumper; 1264 1265 // Support class using when iterating over the heap. 1266 1267 class HeapObjectDumper : public ObjectClosure { 1268 private: 1269 VM_HeapDumper* _dumper; 1270 DumpWriter* _writer; 1271 1272 VM_HeapDumper* dumper() { return _dumper; } 1273 DumpWriter* writer() { return _writer; } 1274 1275 // used to indicate that a record has been writen 1276 void mark_end_of_record(); 1277 1278 public: 1279 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) { 1280 _dumper = dumper; 1281 _writer = writer; 1282 } 1283 1284 // called for each object in the heap 1285 void do_object(oop o); 1286 }; 1287 1288 void HeapObjectDumper::do_object(oop o) { 1289 // hide the sentinel for deleted handles 1290 if (o == JNIHandles::deleted_handle()) return; 1291 1292 // ignore KlassKlass objects 1293 if (o->is_klass()) return; 1294 1295 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records 1296 if (o->klass() == SystemDictionary::Class_klass()) { 1297 if (!java_lang_Class::is_primitive(o)) { 1298 return; 1299 } 1300 } 1301 1302 // create a HPROF_GC_INSTANCE record for each object 1303 if (o->is_instance()) { 1304 DumperSupport::dump_instance(writer(), o); 1305 mark_end_of_record(); 1306 } else { 1307 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array 1308 if (o->is_objArray()) { 1309 DumperSupport::dump_object_array(writer(), objArrayOop(o)); 1310 mark_end_of_record(); 1311 } else { 1312 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array 1313 if (o->is_typeArray()) { 1314 DumperSupport::dump_prim_array(writer(), typeArrayOop(o)); 1315 mark_end_of_record(); 1316 } 1317 } 1318 } 1319 } 1320 1321 // The VM operation that performs the heap dump 1322 class VM_HeapDumper : public VM_GC_Operation { 1323 private: 1324 static VM_HeapDumper* _global_dumper; 1325 static DumpWriter* _global_writer; 1326 DumpWriter* _local_writer; 1327 JavaThread* _oome_thread; 1328 methodOop _oome_constructor; 1329 bool _gc_before_heap_dump; 1330 bool _is_segmented_dump; 1331 jlong _dump_start; 1332 GrowableArray<Klass*>* _klass_map; 1333 ThreadStackTrace** _stack_traces; 1334 int _num_threads; 1335 1336 // accessors and setters 1337 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; } 1338 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; } 1339 void set_global_dumper() { 1340 assert(_global_dumper == NULL, "Error"); 1341 _global_dumper = this; 1342 } 1343 void set_global_writer() { 1344 assert(_global_writer == NULL, "Error"); 1345 _global_writer = _local_writer; 1346 } 1347 void clear_global_dumper() { _global_dumper = NULL; } 1348 void clear_global_writer() { _global_writer = NULL; } 1349 1350 bool is_segmented_dump() const { return _is_segmented_dump; } 1351 void set_segmented_dump() { _is_segmented_dump = true; } 1352 jlong dump_start() const { return _dump_start; } 1353 void set_dump_start(jlong pos); 1354 1355 bool skip_operation() const; 1356 1357 // writes a HPROF_LOAD_CLASS record 1358 static void do_load_class(klassOop k); 1359 1360 // writes a HPROF_GC_CLASS_DUMP record for the given class 1361 // (and each array class too) 1362 static void do_class_dump(klassOop k); 1363 1364 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1365 // array (and each multi-dimensional array too) 1366 static void do_basic_type_array_class_dump(klassOop k); 1367 1368 // HPROF_GC_ROOT_THREAD_OBJ records 1369 int do_thread(JavaThread* thread, u4 thread_serial_num); 1370 void do_threads(); 1371 1372 void add_class_serial_number(Klass* k, int serial_num) { 1373 _klass_map->at_put_grow(serial_num, k); 1374 } 1375 1376 // HPROF_TRACE and HPROF_FRAME records 1377 void dump_stack_traces(); 1378 1379 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record 1380 void write_dump_header(); 1381 1382 // fixes up the length of the current dump record 1383 void write_current_dump_record_length(); 1384 1385 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END 1386 // record in the case of a segmented heap dump) 1387 void end_of_dump(); 1388 1389 public: 1390 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) : 1391 VM_GC_Operation(0 /* total collections, dummy, ignored */, 1392 0 /* total full collections, dummy, ignored */, 1393 gc_before_heap_dump) { 1394 _gc_cause = GCCause::_heap_dump; 1395 _local_writer = writer; 1396 _gc_before_heap_dump = gc_before_heap_dump; 1397 _is_segmented_dump = false; 1398 _dump_start = (jlong)-1; 1399 _klass_map = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true); 1400 _stack_traces = NULL; 1401 _num_threads = 0; 1402 if (oome) { 1403 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread"); 1404 // get OutOfMemoryError zero-parameter constructor 1405 instanceKlass* oome_ik = instanceKlass::cast(SystemDictionary::OutOfMemoryError_klass()); 1406 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(), 1407 vmSymbols::void_method_signature()); 1408 // get thread throwing OOME when generating the heap dump at OOME 1409 _oome_thread = JavaThread::current(); 1410 } else { 1411 _oome_thread = NULL; 1412 _oome_constructor = NULL; 1413 } 1414 } 1415 ~VM_HeapDumper() { 1416 if (_stack_traces != NULL) { 1417 for (int i=0; i < _num_threads; i++) { 1418 delete _stack_traces[i]; 1419 } 1420 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces); 1421 } 1422 delete _klass_map; 1423 } 1424 1425 VMOp_Type type() const { return VMOp_HeapDumper; } 1426 // used to mark sub-record boundary 1427 void check_segment_length(); 1428 void doit(); 1429 }; 1430 1431 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL; 1432 DumpWriter* VM_HeapDumper::_global_writer = NULL; 1433 1434 bool VM_HeapDumper::skip_operation() const { 1435 return false; 1436 } 1437 1438 // sets the dump starting position 1439 void VM_HeapDumper::set_dump_start(jlong pos) { 1440 _dump_start = pos; 1441 } 1442 1443 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record 1444 void VM_HeapDumper::write_dump_header() { 1445 if (writer()->is_open()) { 1446 if (is_segmented_dump()) { 1447 writer()->write_u1(HPROF_HEAP_DUMP_SEGMENT); 1448 } else { 1449 writer()->write_u1(HPROF_HEAP_DUMP); 1450 } 1451 writer()->write_u4(0); // current ticks 1452 1453 // record the starting position for the dump (its length will be fixed up later) 1454 set_dump_start(writer()->current_offset()); 1455 writer()->write_u4(0); 1456 } 1457 } 1458 1459 // fixes up the length of the current dump record 1460 void VM_HeapDumper::write_current_dump_record_length() { 1461 if (writer()->is_open()) { 1462 assert(dump_start() >= 0, "no dump start recorded"); 1463 1464 // calculate the size of the dump record 1465 jlong dump_end = writer()->current_offset(); 1466 jlong dump_len = (dump_end - dump_start() - 4); 1467 1468 // record length must fit in a u4 1469 if (dump_len > (jlong)(4L*(jlong)G)) { 1470 warning("record is too large"); 1471 } 1472 1473 // seek to the dump start and fix-up the length 1474 writer()->seek_to_offset(dump_start()); 1475 writer()->write_u4((u4)dump_len); 1476 1477 // adjust the total size written to keep the bytes written correct. 1478 writer()->adjust_bytes_written(-((long) sizeof(u4))); 1479 1480 // seek to dump end so we can continue 1481 writer()->seek_to_offset(dump_end); 1482 1483 // no current dump record 1484 set_dump_start((jlong)-1); 1485 } 1486 } 1487 1488 // used on a sub-record boundary to check if we need to start a 1489 // new segment. 1490 void VM_HeapDumper::check_segment_length() { 1491 if (writer()->is_open()) { 1492 if (is_segmented_dump()) { 1493 // don't use current_offset that would be too expensive on a per record basis 1494 jlong dump_end = writer()->bytes_written() + writer()->bytes_unwritten(); 1495 assert(dump_end == writer()->current_offset(), "checking"); 1496 jlong dump_len = (dump_end - dump_start() - 4); 1497 assert(dump_len >= 0 && dump_len <= max_juint, "bad dump length"); 1498 1499 if (dump_len > (jlong)HeapDumpSegmentSize) { 1500 write_current_dump_record_length(); 1501 write_dump_header(); 1502 } 1503 } 1504 } 1505 } 1506 1507 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END 1508 // record in the case of a segmented heap dump) 1509 void VM_HeapDumper::end_of_dump() { 1510 if (writer()->is_open()) { 1511 write_current_dump_record_length(); 1512 1513 // for segmented dump we write the end record 1514 if (is_segmented_dump()) { 1515 writer()->write_u1(HPROF_HEAP_DUMP_END); 1516 writer()->write_u4(0); 1517 writer()->write_u4(0); 1518 } 1519 } 1520 } 1521 1522 // marks sub-record boundary 1523 void HeapObjectDumper::mark_end_of_record() { 1524 dumper()->check_segment_length(); 1525 } 1526 1527 // writes a HPROF_LOAD_CLASS record for the class (and each of its 1528 // array classes) 1529 void VM_HeapDumper::do_load_class(klassOop k) { 1530 static u4 class_serial_num = 0; 1531 1532 // len of HPROF_LOAD_CLASS record 1533 u4 remaining = 2*oopSize + 2*sizeof(u4); 1534 1535 // write a HPROF_LOAD_CLASS for the class and each array class 1536 do { 1537 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining); 1538 1539 // class serial number is just a number 1540 writer()->write_u4(++class_serial_num); 1541 1542 // class ID 1543 Klass* klass = Klass::cast(k); 1544 writer()->write_classID(klass); 1545 1546 // add the klassOop and class serial number pair 1547 dumper()->add_class_serial_number(klass, class_serial_num); 1548 1549 writer()->write_u4(STACK_TRACE_ID); 1550 1551 // class name ID 1552 symbolOop name = klass->name(); 1553 writer()->write_objectID(name); 1554 1555 // write a LOAD_CLASS record for the array type (if it exists) 1556 k = klass->array_klass_or_null(); 1557 } while (k != NULL); 1558 } 1559 1560 // writes a HPROF_GC_CLASS_DUMP record for the given class 1561 void VM_HeapDumper::do_class_dump(klassOop k) { 1562 DumperSupport::dump_class_and_array_classes(writer(), k); 1563 } 1564 1565 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1566 // array (and each multi-dimensional array too) 1567 void VM_HeapDumper::do_basic_type_array_class_dump(klassOop k) { 1568 DumperSupport::dump_basic_type_array_class(writer(), k); 1569 } 1570 1571 // Walk the stack of the given thread. 1572 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local 1573 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local 1574 // 1575 // It returns the number of Java frames in this thread stack 1576 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) { 1577 JNILocalsDumper blk(writer(), thread_serial_num); 1578 1579 oop threadObj = java_thread->threadObj(); 1580 assert(threadObj != NULL, "sanity check"); 1581 1582 int stack_depth = 0; 1583 if (java_thread->has_last_Java_frame()) { 1584 1585 // vframes are resource allocated 1586 Thread* current_thread = Thread::current(); 1587 ResourceMark rm(current_thread); 1588 HandleMark hm(current_thread); 1589 1590 RegisterMap reg_map(java_thread); 1591 frame f = java_thread->last_frame(); 1592 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread); 1593 frame* last_entry_frame = NULL; 1594 int extra_frames = 0; 1595 1596 if (java_thread == _oome_thread && _oome_constructor != NULL) { 1597 extra_frames++; 1598 } 1599 while (vf != NULL) { 1600 blk.set_frame_number(stack_depth); 1601 if (vf->is_java_frame()) { 1602 1603 // java frame (interpreted, compiled, ...) 1604 javaVFrame *jvf = javaVFrame::cast(vf); 1605 if (!(jvf->method()->is_native())) { 1606 StackValueCollection* locals = jvf->locals(); 1607 for (int slot=0; slot<locals->size(); slot++) { 1608 if (locals->at(slot)->type() == T_OBJECT) { 1609 oop o = locals->obj_at(slot)(); 1610 1611 if (o != NULL) { 1612 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME); 1613 writer()->write_objectID(o); 1614 writer()->write_u4(thread_serial_num); 1615 writer()->write_u4((u4) (stack_depth + extra_frames)); 1616 } 1617 } 1618 } 1619 } else { 1620 // native frame 1621 if (stack_depth == 0) { 1622 // JNI locals for the top frame. 1623 java_thread->active_handles()->oops_do(&blk); 1624 } else { 1625 if (last_entry_frame != NULL) { 1626 // JNI locals for the entry frame 1627 assert(last_entry_frame->is_entry_frame(), "checking"); 1628 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk); 1629 } 1630 } 1631 } 1632 // increment only for Java frames 1633 stack_depth++; 1634 last_entry_frame = NULL; 1635 1636 } else { 1637 // externalVFrame - if it's an entry frame then report any JNI locals 1638 // as roots when we find the corresponding native javaVFrame 1639 frame* fr = vf->frame_pointer(); 1640 assert(fr != NULL, "sanity check"); 1641 if (fr->is_entry_frame()) { 1642 last_entry_frame = fr; 1643 } 1644 } 1645 vf = vf->sender(); 1646 } 1647 } else { 1648 // no last java frame but there may be JNI locals 1649 java_thread->active_handles()->oops_do(&blk); 1650 } 1651 return stack_depth; 1652 } 1653 1654 1655 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk 1656 // the stack so that locals and JNI locals are dumped. 1657 void VM_HeapDumper::do_threads() { 1658 for (int i=0; i < _num_threads; i++) { 1659 JavaThread* thread = _stack_traces[i]->thread(); 1660 oop threadObj = thread->threadObj(); 1661 u4 thread_serial_num = i+1; 1662 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID; 1663 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ); 1664 writer()->write_objectID(threadObj); 1665 writer()->write_u4(thread_serial_num); // thread number 1666 writer()->write_u4(stack_serial_num); // stack trace serial number 1667 int num_frames = do_thread(thread, thread_serial_num); 1668 assert(num_frames == _stack_traces[i]->get_stack_depth(), 1669 "total number of Java frames not matched"); 1670 } 1671 } 1672 1673 1674 // The VM operation that dumps the heap. The dump consists of the following 1675 // records: 1676 // 1677 // HPROF_HEADER 1678 // [HPROF_UTF8]* 1679 // [HPROF_LOAD_CLASS]* 1680 // [[HPROF_FRAME]*|HPROF_TRACE]* 1681 // [HPROF_GC_CLASS_DUMP]* 1682 // HPROF_HEAP_DUMP 1683 // 1684 // The HPROF_TRACE records represent the stack traces where the heap dump 1685 // is generated and a "dummy trace" record which does not include 1686 // any frames. The dummy trace record is used to be referenced as the 1687 // unknown object alloc site. 1688 // 1689 // The HPROF_HEAP_DUMP record has a length following by sub-records. To allow 1690 // the heap dump be generated in a single pass we remember the position of 1691 // the dump length and fix it up after all sub-records have been written. 1692 // To generate the sub-records we iterate over the heap, writing 1693 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP 1694 // records as we go. Once that is done we write records for some of the GC 1695 // roots. 1696 1697 void VM_HeapDumper::doit() { 1698 1699 HandleMark hm; 1700 CollectedHeap* ch = Universe::heap(); 1701 if (_gc_before_heap_dump) { 1702 ch->collect_as_vm_thread(GCCause::_heap_dump); 1703 } else { 1704 // make the heap parsable (no need to retire TLABs) 1705 ch->ensure_parsability(false); 1706 } 1707 1708 // At this point we should be the only dumper active, so 1709 // the following should be safe. 1710 set_global_dumper(); 1711 set_global_writer(); 1712 1713 // Write the file header - use 1.0.2 for large heaps, otherwise 1.0.1 1714 size_t used = ch->used(); 1715 const char* header; 1716 if (used > (size_t)SegmentedHeapDumpThreshold) { 1717 set_segmented_dump(); 1718 header = "JAVA PROFILE 1.0.2"; 1719 } else { 1720 header = "JAVA PROFILE 1.0.1"; 1721 } 1722 1723 // header is few bytes long - no chance to overflow int 1724 writer()->write_raw((void*)header, (int)strlen(header)); 1725 writer()->write_u1(0); // terminator 1726 writer()->write_u4(oopSize); 1727 writer()->write_u8(os::javaTimeMillis()); 1728 1729 // HPROF_UTF8 records 1730 SymbolTableDumper sym_dumper(writer()); 1731 SymbolTable::oops_do(&sym_dumper); 1732 1733 // write HPROF_LOAD_CLASS records 1734 SystemDictionary::classes_do(&do_load_class); 1735 Universe::basic_type_classes_do(&do_load_class); 1736 1737 // write HPROF_FRAME and HPROF_TRACE records 1738 // this must be called after _klass_map is built when iterating the classes above. 1739 dump_stack_traces(); 1740 1741 // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT 1742 write_dump_header(); 1743 1744 // Writes HPROF_GC_CLASS_DUMP records 1745 SystemDictionary::classes_do(&do_class_dump); 1746 Universe::basic_type_classes_do(&do_basic_type_array_class_dump); 1747 check_segment_length(); 1748 1749 // writes HPROF_GC_INSTANCE_DUMP records. 1750 // After each sub-record is written check_segment_length will be invoked. When 1751 // generated a segmented heap dump this allows us to check if the current 1752 // segment exceeds a threshold and if so, then a new segment is started. 1753 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk 1754 // of the heap dump. 1755 HeapObjectDumper obj_dumper(this, writer()); 1756 Universe::heap()->safe_object_iterate(&obj_dumper); 1757 1758 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals 1759 do_threads(); 1760 check_segment_length(); 1761 1762 // HPROF_GC_ROOT_MONITOR_USED 1763 MonitorUsedDumper mon_dumper(writer()); 1764 ObjectSynchronizer::oops_do(&mon_dumper); 1765 check_segment_length(); 1766 1767 // HPROF_GC_ROOT_JNI_GLOBAL 1768 JNIGlobalsDumper jni_dumper(writer()); 1769 JNIHandles::oops_do(&jni_dumper); 1770 check_segment_length(); 1771 1772 // HPROF_GC_ROOT_STICKY_CLASS 1773 StickyClassDumper class_dumper(writer()); 1774 SystemDictionary::always_strong_oops_do(&class_dumper); 1775 1776 // fixes up the length of the dump record. In the case of a segmented 1777 // heap then the HPROF_HEAP_DUMP_END record is also written. 1778 end_of_dump(); 1779 1780 // Now we clear the global variables, so that a future dumper might run. 1781 clear_global_dumper(); 1782 clear_global_writer(); 1783 } 1784 1785 void VM_HeapDumper::dump_stack_traces() { 1786 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites 1787 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4)); 1788 writer()->write_u4((u4) STACK_TRACE_ID); 1789 writer()->write_u4(0); // thread number 1790 writer()->write_u4(0); // frame count 1791 1792 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads()); 1793 int frame_serial_num = 0; 1794 for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) { 1795 oop threadObj = thread->threadObj(); 1796 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) { 1797 // dump thread stack trace 1798 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false); 1799 stack_trace->dump_stack_at_safepoint(-1); 1800 _stack_traces[_num_threads++] = stack_trace; 1801 1802 // write HPROF_FRAME records for this thread's stack trace 1803 int depth = stack_trace->get_stack_depth(); 1804 int thread_frame_start = frame_serial_num; 1805 int extra_frames = 0; 1806 // write fake frame that makes it look like the thread, which caused OOME, 1807 // is in the OutOfMemoryError zero-parameter constructor 1808 if (thread == _oome_thread && _oome_constructor != NULL) { 1809 int oome_serial_num = _klass_map->find(Klass::cast(_oome_constructor->method_holder())); 1810 // the class serial number starts from 1 1811 assert(oome_serial_num > 0, "OutOfMemoryError class not found"); 1812 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num, 1813 _oome_constructor, 0); 1814 extra_frames++; 1815 } 1816 for (int j=0; j < depth; j++) { 1817 StackFrameInfo* frame = stack_trace->stack_frame_at(j); 1818 methodOop m = frame->method(); 1819 int class_serial_num = _klass_map->find(Klass::cast(m->method_holder())); 1820 // the class serial number starts from 1 1821 assert(class_serial_num > 0, "class not found"); 1822 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci()); 1823 } 1824 depth += extra_frames; 1825 1826 // write HPROF_TRACE record for one thread 1827 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize); 1828 int stack_serial_num = _num_threads + STACK_TRACE_ID; 1829 writer()->write_u4(stack_serial_num); // stack trace serial number 1830 writer()->write_u4((u4) _num_threads); // thread serial number 1831 writer()->write_u4(depth); // frame count 1832 for (int j=1; j <= depth; j++) { 1833 writer()->write_id(thread_frame_start + j); 1834 } 1835 } 1836 } 1837 } 1838 1839 // dump the heap to given path. 1840 int HeapDumper::dump(const char* path) { 1841 assert(path != NULL && strlen(path) > 0, "path missing"); 1842 1843 // print message in interactive case 1844 if (print_to_tty()) { 1845 tty->print_cr("Dumping heap to %s ...", path); 1846 timer()->start(); 1847 } 1848 1849 // create the dump writer. If the file can be opened then bail 1850 DumpWriter writer(path); 1851 if (!writer.is_open()) { 1852 set_error(writer.error()); 1853 if (print_to_tty()) { 1854 tty->print_cr("Unable to create %s: %s", path, 1855 (error() != NULL) ? error() : "reason unknown"); 1856 } 1857 return -1; 1858 } 1859 1860 // generate the dump 1861 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome); 1862 if (Thread::current()->is_VM_thread()) { 1863 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint"); 1864 dumper.doit(); 1865 } else { 1866 VMThread::execute(&dumper); 1867 } 1868 1869 // close dump file and record any error that the writer may have encountered 1870 writer.close(); 1871 set_error(writer.error()); 1872 1873 // print message in interactive case 1874 if (print_to_tty()) { 1875 timer()->stop(); 1876 if (error() == NULL) { 1877 char msg[256]; 1878 sprintf(msg, "Heap dump file created [%s bytes in %3.3f secs]", 1879 os::jlong_format_specifier(), timer()->seconds()); 1880 tty->print_cr(msg, writer.bytes_written()); 1881 } else { 1882 tty->print_cr("Dump file is incomplete: %s", writer.error()); 1883 } 1884 } 1885 1886 return (writer.error() == NULL) ? 0 : -1; 1887 } 1888 1889 // stop timer (if still active), and free any error string we might be holding 1890 HeapDumper::~HeapDumper() { 1891 if (timer()->is_active()) { 1892 timer()->stop(); 1893 } 1894 set_error(NULL); 1895 } 1896 1897 1898 // returns the error string (resource allocated), or NULL 1899 char* HeapDumper::error_as_C_string() const { 1900 if (error() != NULL) { 1901 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1); 1902 strcpy(str, error()); 1903 return str; 1904 } else { 1905 return NULL; 1906 } 1907 } 1908 1909 // set the error string 1910 void HeapDumper::set_error(char* error) { 1911 if (_error != NULL) { 1912 os::free(_error); 1913 } 1914 if (error == NULL) { 1915 _error = NULL; 1916 } else { 1917 _error = os::strdup(error); 1918 assert(_error != NULL, "allocation failure"); 1919 } 1920 } 1921 1922 // Called by out-of-memory error reporting by a single Java thread 1923 // outside of a JVM safepoint 1924 void HeapDumper::dump_heap_from_oome() { 1925 HeapDumper::dump_heap(true); 1926 } 1927 1928 // Called by error reporting by a single Java thread outside of a JVM safepoint, 1929 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various 1930 // callers are strictly serialized and guaranteed not to interfere below. For more 1931 // general use, however, this method will need modification to prevent 1932 // inteference when updating the static variables base_path and dump_file_seq below. 1933 void HeapDumper::dump_heap() { 1934 HeapDumper::dump_heap(false); 1935 } 1936 1937 void HeapDumper::dump_heap(bool oome) { 1938 static char base_path[JVM_MAXPATHLEN] = {'\0'}; 1939 static uint dump_file_seq = 0; 1940 char* my_path; 1941 const int max_digit_chars = 20; 1942 1943 const char* dump_file_name = "java_pid"; 1944 const char* dump_file_ext = ".hprof"; 1945 1946 // The dump file defaults to java_pid<pid>.hprof in the current working 1947 // directory. HeapDumpPath=<file> can be used to specify an alternative 1948 // dump file name or a directory where dump file is created. 1949 if (dump_file_seq == 0) { // first time in, we initialize base_path 1950 // Calculate potentially longest base path and check if we have enough 1951 // allocated statically. 1952 const size_t total_length = 1953 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) + 1954 strlen(os::file_separator()) + max_digit_chars + 1955 strlen(dump_file_name) + strlen(dump_file_ext) + 1; 1956 if (total_length > sizeof(base_path)) { 1957 warning("Cannot create heap dump file. HeapDumpPath is too long."); 1958 return; 1959 } 1960 1961 bool use_default_filename = true; 1962 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') { 1963 // HeapDumpPath=<file> not specified 1964 } else { 1965 strncpy(base_path, HeapDumpPath, sizeof(base_path)); 1966 // check if the path is a directory (must exist) 1967 DIR* dir = os::opendir(base_path); 1968 if (dir == NULL) { 1969 use_default_filename = false; 1970 } else { 1971 // HeapDumpPath specified a directory. We append a file separator 1972 // (if needed). 1973 os::closedir(dir); 1974 size_t fs_len = strlen(os::file_separator()); 1975 if (strlen(base_path) >= fs_len) { 1976 char* end = base_path; 1977 end += (strlen(base_path) - fs_len); 1978 if (strcmp(end, os::file_separator()) != 0) { 1979 strcat(base_path, os::file_separator()); 1980 } 1981 } 1982 } 1983 } 1984 // If HeapDumpPath wasn't a file name then we append the default name 1985 if (use_default_filename) { 1986 const size_t dlen = strlen(base_path); // if heap dump dir specified 1987 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s", 1988 dump_file_name, os::current_process_id(), dump_file_ext); 1989 } 1990 const size_t len = strlen(base_path) + 1; 1991 my_path = (char*)os::malloc(len); 1992 if (my_path == NULL) { 1993 warning("Cannot create heap dump file. Out of system memory."); 1994 return; 1995 } 1996 strncpy(my_path, base_path, len); 1997 } else { 1998 // Append a sequence number id for dumps following the first 1999 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0 2000 my_path = (char*)os::malloc(len); 2001 if (my_path == NULL) { 2002 warning("Cannot create heap dump file. Out of system memory."); 2003 return; 2004 } 2005 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq); 2006 } 2007 dump_file_seq++; // increment seq number for next time we dump 2008 2009 HeapDumper dumper(false /* no GC before heap dump */, 2010 true /* send to tty */, 2011 oome /* pass along out-of-memory-error flag */); 2012 dumper.dump(my_path); 2013 os::free(my_path); 2014 }