1 /* 2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "classfile/symbolTable.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "classfile/vmSymbols.hpp" 29 #include "gc_implementation/shared/vmGCOperations.hpp" 30 #include "memory/gcLocker.inline.hpp" 31 #include "memory/genCollectedHeap.hpp" 32 #include "memory/universe.hpp" 33 #include "oops/objArrayKlass.hpp" 34 #include "runtime/javaCalls.hpp" 35 #include "runtime/jniHandles.hpp" 36 #include "runtime/reflectionUtils.hpp" 37 #include "runtime/vframe.hpp" 38 #include "runtime/vmThread.hpp" 39 #include "runtime/vm_operations.hpp" 40 #include "services/heapDumper.hpp" 41 #include "services/threadService.hpp" 42 #include "utilities/ostream.hpp" 43 #include "utilities/macros.hpp" 44 #if INCLUDE_ALL_GCS 45 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" 46 #endif // INCLUDE_ALL_GCS 47 48 /* 49 * HPROF binary format - description copied from: 50 * src/share/demo/jvmti/hprof/hprof_io.c 51 * 52 * 53 * header "JAVA PROFILE 1.0.1" or "JAVA PROFILE 1.0.2" 54 * (0-terminated) 55 * 56 * u4 size of identifiers. Identifiers are used to represent 57 * UTF8 strings, objects, stack traces, etc. They usually 58 * have the same size as host pointers. For example, on 59 * Solaris and Win32, the size is 4. 60 * u4 high word 61 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70 62 * [record]* a sequence of records. 63 * 64 * 65 * Record format: 66 * 67 * u1 a TAG denoting the type of the record 68 * u4 number of *microseconds* since the time stamp in the 69 * header. (wraps around in a little more than an hour) 70 * u4 number of bytes *remaining* in the record. Note that 71 * this number excludes the tag and the length field itself. 72 * [u1]* BODY of the record (a sequence of bytes) 73 * 74 * 75 * The following TAGs are supported: 76 * 77 * TAG BODY notes 78 *---------------------------------------------------------- 79 * HPROF_UTF8 a UTF8-encoded name 80 * 81 * id name ID 82 * [u1]* UTF8 characters (no trailing zero) 83 * 84 * HPROF_LOAD_CLASS a newly loaded class 85 * 86 * u4 class serial number (> 0) 87 * id class object ID 88 * u4 stack trace serial number 89 * id class name ID 90 * 91 * HPROF_UNLOAD_CLASS an unloading class 92 * 93 * u4 class serial_number 94 * 95 * HPROF_FRAME a Java stack frame 96 * 97 * id stack frame ID 98 * id method name ID 99 * id method signature ID 100 * id source file name ID 101 * u4 class serial number 102 * i4 line number. >0: normal 103 * -1: unknown 104 * -2: compiled method 105 * -3: native method 106 * 107 * HPROF_TRACE a Java stack trace 108 * 109 * u4 stack trace serial number 110 * u4 thread serial number 111 * u4 number of frames 112 * [id]* stack frame IDs 113 * 114 * 115 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC 116 * 117 * u2 flags 0x0001: incremental vs. complete 118 * 0x0002: sorted by allocation vs. live 119 * 0x0004: whether to force a GC 120 * u4 cutoff ratio 121 * u4 total live bytes 122 * u4 total live instances 123 * u8 total bytes allocated 124 * u8 total instances allocated 125 * u4 number of sites that follow 126 * [u1 is_array: 0: normal object 127 * 2: object array 128 * 4: boolean array 129 * 5: char array 130 * 6: float array 131 * 7: double array 132 * 8: byte array 133 * 9: short array 134 * 10: int array 135 * 11: long array 136 * u4 class serial number (may be zero during startup) 137 * u4 stack trace serial number 138 * u4 number of bytes alive 139 * u4 number of instances alive 140 * u4 number of bytes allocated 141 * u4]* number of instance allocated 142 * 143 * HPROF_START_THREAD a newly started thread. 144 * 145 * u4 thread serial number (> 0) 146 * id thread object ID 147 * u4 stack trace serial number 148 * id thread name ID 149 * id thread group name ID 150 * id thread group parent name ID 151 * 152 * HPROF_END_THREAD a terminating thread. 153 * 154 * u4 thread serial number 155 * 156 * HPROF_HEAP_SUMMARY heap summary 157 * 158 * u4 total live bytes 159 * u4 total live instances 160 * u8 total bytes allocated 161 * u8 total instances allocated 162 * 163 * HPROF_HEAP_DUMP denote a heap dump 164 * 165 * [heap dump sub-records]* 166 * 167 * There are four kinds of heap dump sub-records: 168 * 169 * u1 sub-record type 170 * 171 * HPROF_GC_ROOT_UNKNOWN unknown root 172 * 173 * id object ID 174 * 175 * HPROF_GC_ROOT_THREAD_OBJ thread object 176 * 177 * id thread object ID (may be 0 for a 178 * thread newly attached through JNI) 179 * u4 thread sequence number 180 * u4 stack trace sequence number 181 * 182 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root 183 * 184 * id object ID 185 * id JNI global ref ID 186 * 187 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref 188 * 189 * id object ID 190 * u4 thread serial number 191 * u4 frame # in stack trace (-1 for empty) 192 * 193 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame 194 * 195 * id object ID 196 * u4 thread serial number 197 * u4 frame # in stack trace (-1 for empty) 198 * 199 * HPROF_GC_ROOT_NATIVE_STACK Native stack 200 * 201 * id object ID 202 * u4 thread serial number 203 * 204 * HPROF_GC_ROOT_STICKY_CLASS System class 205 * 206 * id object ID 207 * 208 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block 209 * 210 * id object ID 211 * u4 thread serial number 212 * 213 * HPROF_GC_ROOT_MONITOR_USED Busy monitor 214 * 215 * id object ID 216 * 217 * HPROF_GC_CLASS_DUMP dump of a class object 218 * 219 * id class object ID 220 * u4 stack trace serial number 221 * id super class object ID 222 * id class loader object ID 223 * id signers object ID 224 * id protection domain object ID 225 * id reserved 226 * id reserved 227 * 228 * u4 instance size (in bytes) 229 * 230 * u2 size of constant pool 231 * [u2, constant pool index, 232 * ty, type 233 * 2: object 234 * 4: boolean 235 * 5: char 236 * 6: float 237 * 7: double 238 * 8: byte 239 * 9: short 240 * 10: int 241 * 11: long 242 * vl]* and value 243 * 244 * u2 number of static fields 245 * [id, static field name, 246 * ty, type, 247 * vl]* and value 248 * 249 * u2 number of inst. fields (not inc. super) 250 * [id, instance field name, 251 * ty]* type 252 * 253 * HPROF_GC_INSTANCE_DUMP dump of a normal object 254 * 255 * id object ID 256 * u4 stack trace serial number 257 * id class object ID 258 * u4 number of bytes that follow 259 * [vl]* instance field values (class, followed 260 * by super, super's super ...) 261 * 262 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array 263 * 264 * id array object ID 265 * u4 stack trace serial number 266 * u4 number of elements 267 * id array class ID 268 * [id]* elements 269 * 270 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array 271 * 272 * id array object ID 273 * u4 stack trace serial number 274 * u4 number of elements 275 * u1 element type 276 * 4: boolean array 277 * 5: char array 278 * 6: float array 279 * 7: double array 280 * 8: byte array 281 * 9: short array 282 * 10: int array 283 * 11: long array 284 * [u1]* elements 285 * 286 * HPROF_CPU_SAMPLES a set of sample traces of running threads 287 * 288 * u4 total number of samples 289 * u4 # of traces 290 * [u4 # of samples 291 * u4]* stack trace serial number 292 * 293 * HPROF_CONTROL_SETTINGS the settings of on/off switches 294 * 295 * u4 0x00000001: alloc traces on/off 296 * 0x00000002: cpu sampling on/off 297 * u2 stack trace depth 298 * 299 * 300 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally 301 * be generated as a sequence of heap dump segments. This sequence is 302 * terminated by an end record. The additional tags allowed by format 303 * "JAVA PROFILE 1.0.2" are: 304 * 305 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment 306 * 307 * [heap dump sub-records]* 308 * The same sub-record types allowed by HPROF_HEAP_DUMP 309 * 310 * HPROF_HEAP_DUMP_END denotes the end of a heap dump 311 * 312 */ 313 314 315 // HPROF tags 316 317 typedef enum { 318 // top-level records 319 HPROF_UTF8 = 0x01, 320 HPROF_LOAD_CLASS = 0x02, 321 HPROF_UNLOAD_CLASS = 0x03, 322 HPROF_FRAME = 0x04, 323 HPROF_TRACE = 0x05, 324 HPROF_ALLOC_SITES = 0x06, 325 HPROF_HEAP_SUMMARY = 0x07, 326 HPROF_START_THREAD = 0x0A, 327 HPROF_END_THREAD = 0x0B, 328 HPROF_HEAP_DUMP = 0x0C, 329 HPROF_CPU_SAMPLES = 0x0D, 330 HPROF_CONTROL_SETTINGS = 0x0E, 331 332 // 1.0.2 record types 333 HPROF_HEAP_DUMP_SEGMENT = 0x1C, 334 HPROF_HEAP_DUMP_END = 0x2C, 335 336 // field types 337 HPROF_ARRAY_OBJECT = 0x01, 338 HPROF_NORMAL_OBJECT = 0x02, 339 HPROF_BOOLEAN = 0x04, 340 HPROF_CHAR = 0x05, 341 HPROF_FLOAT = 0x06, 342 HPROF_DOUBLE = 0x07, 343 HPROF_BYTE = 0x08, 344 HPROF_SHORT = 0x09, 345 HPROF_INT = 0x0A, 346 HPROF_LONG = 0x0B, 347 348 // data-dump sub-records 349 HPROF_GC_ROOT_UNKNOWN = 0xFF, 350 HPROF_GC_ROOT_JNI_GLOBAL = 0x01, 351 HPROF_GC_ROOT_JNI_LOCAL = 0x02, 352 HPROF_GC_ROOT_JAVA_FRAME = 0x03, 353 HPROF_GC_ROOT_NATIVE_STACK = 0x04, 354 HPROF_GC_ROOT_STICKY_CLASS = 0x05, 355 HPROF_GC_ROOT_THREAD_BLOCK = 0x06, 356 HPROF_GC_ROOT_MONITOR_USED = 0x07, 357 HPROF_GC_ROOT_THREAD_OBJ = 0x08, 358 HPROF_GC_CLASS_DUMP = 0x20, 359 HPROF_GC_INSTANCE_DUMP = 0x21, 360 HPROF_GC_OBJ_ARRAY_DUMP = 0x22, 361 HPROF_GC_PRIM_ARRAY_DUMP = 0x23 362 } hprofTag; 363 364 // Default stack trace ID (used for dummy HPROF_TRACE record) 365 enum { 366 STACK_TRACE_ID = 1, 367 INITIAL_CLASS_COUNT = 200 368 }; 369 370 // Supports I/O operations on a dump file 371 372 class DumpWriter : public StackObj { 373 private: 374 enum { 375 io_buffer_size = 8*M 376 }; 377 378 int _fd; // file descriptor (-1 if dump file not open) 379 julong _bytes_written; // number of byte written to dump file 380 381 char* _buffer; // internal buffer 382 size_t _size; 383 size_t _pos; 384 385 char* _error; // error message when I/O fails 386 387 void set_file_descriptor(int fd) { _fd = fd; } 388 int file_descriptor() const { return _fd; } 389 390 char* buffer() const { return _buffer; } 391 size_t buffer_size() const { return _size; } 392 size_t position() const { return _pos; } 393 void set_position(size_t pos) { _pos = pos; } 394 395 void set_error(const char* error) { _error = (char*)os::strdup(error); } 396 397 // all I/O go through this function 398 void write_internal(void* s, size_t len); 399 400 public: 401 DumpWriter(const char* path); 402 ~DumpWriter(); 403 404 void close(); 405 bool is_open() const { return file_descriptor() >= 0; } 406 void flush(); 407 408 // total number of bytes written to the disk 409 julong bytes_written() const { return _bytes_written; } 410 411 // adjust the number of bytes written to disk (used to keep the count 412 // of the number of bytes written in case of rewrites) 413 void adjust_bytes_written(jlong n) { _bytes_written += n; } 414 415 // number of (buffered) bytes as yet unwritten to the dump file 416 size_t bytes_unwritten() const { return position(); } 417 418 char* error() const { return _error; } 419 420 jlong current_offset(); 421 void seek_to_offset(jlong pos); 422 423 // writer functions 424 void write_raw(void* s, size_t len); 425 void write_u1(u1 x) { write_raw((void*)&x, 1); } 426 void write_u2(u2 x); 427 void write_u4(u4 x); 428 void write_u8(u8 x); 429 void write_objectID(oop o); 430 void write_symbolID(Symbol* o); 431 void write_classID(Klass* k); 432 void write_id(u4 x); 433 }; 434 435 DumpWriter::DumpWriter(const char* path) { 436 // try to allocate an I/O buffer of io_buffer_size. If there isn't 437 // sufficient memory then reduce size until we can allocate something. 438 _size = io_buffer_size; 439 do { 440 _buffer = (char*)os::malloc(_size, mtInternal); 441 if (_buffer == NULL) { 442 _size = _size >> 1; 443 } 444 } while (_buffer == NULL && _size > 0); 445 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check"); 446 _pos = 0; 447 _error = NULL; 448 _bytes_written = 0L; 449 _fd = os::create_binary_file(path, false); // don't replace existing file 450 451 // if the open failed we record the error 452 if (_fd < 0) { 453 _error = (char*)os::strdup(strerror(errno)); 454 } 455 } 456 457 DumpWriter::~DumpWriter() { 458 // flush and close dump file 459 if (is_open()) { 460 close(); 461 } 462 if (_buffer != NULL) os::free(_buffer); 463 if (_error != NULL) os::free(_error); 464 } 465 466 // closes dump file (if open) 467 void DumpWriter::close() { 468 // flush and close dump file 469 if (is_open()) { 470 flush(); 471 ::close(file_descriptor()); 472 set_file_descriptor(-1); 473 } 474 } 475 476 // write directly to the file 477 void DumpWriter::write_internal(void* s, size_t len) { 478 if (is_open()) { 479 const char* pos = (char*)s; 480 ssize_t n = 0; 481 while (len > 0) { 482 uint tmp = (uint)MIN2(len, (size_t)UINT_MAX); 483 n = ::write(file_descriptor(), pos, tmp); 484 485 if (n < 0) { 486 set_error(strerror(errno)); 487 ::close(file_descriptor()); 488 set_file_descriptor(-1); 489 return; 490 } 491 492 _bytes_written += n; 493 pos += n; 494 len -= n; 495 } 496 } 497 } 498 499 // write raw bytes 500 void DumpWriter::write_raw(void* s, size_t len) { 501 if (is_open()) { 502 // flush buffer to make room 503 if ((position() + len) >= buffer_size()) { 504 flush(); 505 } 506 507 // buffer not available or too big to buffer it 508 if ((buffer() == NULL) || (len >= buffer_size())) { 509 write_internal(s, len); 510 } else { 511 // Should optimize this for u1/u2/u4/u8 sizes. 512 memcpy(buffer() + position(), s, len); 513 set_position(position() + len); 514 } 515 } 516 } 517 518 // flush any buffered bytes to the file 519 void DumpWriter::flush() { 520 if (is_open() && position() > 0) { 521 write_internal(buffer(), position()); 522 set_position(0); 523 } 524 } 525 526 jlong DumpWriter::current_offset() { 527 if (is_open()) { 528 // the offset is the file offset plus whatever we have buffered 529 jlong offset = os::current_file_offset(file_descriptor()); 530 assert(offset >= 0, "lseek failed"); 531 return offset + position(); 532 } else { 533 return (jlong)-1; 534 } 535 } 536 537 void DumpWriter::seek_to_offset(jlong off) { 538 assert(off >= 0, "bad offset"); 539 540 // need to flush before seeking 541 flush(); 542 543 // may be closed due to I/O error 544 if (is_open()) { 545 jlong n = os::seek_to_file_offset(file_descriptor(), off); 546 assert(n >= 0, "lseek failed"); 547 } 548 } 549 550 void DumpWriter::write_u2(u2 x) { 551 u2 v; 552 Bytes::put_Java_u2((address)&v, x); 553 write_raw((void*)&v, 2); 554 } 555 556 void DumpWriter::write_u4(u4 x) { 557 u4 v; 558 Bytes::put_Java_u4((address)&v, x); 559 write_raw((void*)&v, 4); 560 } 561 562 void DumpWriter::write_u8(u8 x) { 563 u8 v; 564 Bytes::put_Java_u8((address)&v, x); 565 write_raw((void*)&v, 8); 566 } 567 568 void DumpWriter::write_objectID(oop o) { 569 address a = (address)o; 570 #ifdef _LP64 571 write_u8((u8)a); 572 #else 573 write_u4((u4)a); 574 #endif 575 } 576 577 void DumpWriter::write_symbolID(Symbol* s) { 578 address a = (address)((uintptr_t)s); 579 #ifdef _LP64 580 write_u8((u8)a); 581 #else 582 write_u4((u4)a); 583 #endif 584 } 585 586 void DumpWriter::write_id(u4 x) { 587 #ifdef _LP64 588 write_u8((u8) x); 589 #else 590 write_u4(x); 591 #endif 592 } 593 594 // We use java mirror as the class ID 595 void DumpWriter::write_classID(Klass* k) { 596 write_objectID(k->java_mirror()); 597 } 598 599 600 601 // Support class with a collection of functions used when dumping the heap 602 603 class DumperSupport : AllStatic { 604 public: 605 606 // write a header of the given type 607 static void write_header(DumpWriter* writer, hprofTag tag, u4 len); 608 609 // returns hprof tag for the given type signature 610 static hprofTag sig2tag(Symbol* sig); 611 // returns hprof tag for the given basic type 612 static hprofTag type2tag(BasicType type); 613 614 // returns the size of the instance of the given class 615 static u4 instance_size(Klass* k); 616 617 // dump a jfloat 618 static void dump_float(DumpWriter* writer, jfloat f); 619 // dump a jdouble 620 static void dump_double(DumpWriter* writer, jdouble d); 621 // dumps the raw value of the given field 622 static void dump_field_value(DumpWriter* writer, char type, address addr); 623 // dumps static fields of the given class 624 static void dump_static_fields(DumpWriter* writer, Klass* k); 625 // dump the raw values of the instance fields of the given object 626 static void dump_instance_fields(DumpWriter* writer, oop o); 627 // dumps the definition of the instance fields for a given class 628 static void dump_instance_field_descriptors(DumpWriter* writer, Klass* k); 629 // creates HPROF_GC_INSTANCE_DUMP record for the given object 630 static void dump_instance(DumpWriter* writer, oop o); 631 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its 632 // array classes 633 static void dump_class_and_array_classes(DumpWriter* writer, Klass* k); 634 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 635 // class (and each multi-dimensional array class too) 636 static void dump_basic_type_array_class(DumpWriter* writer, Klass* k); 637 638 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 639 static void dump_object_array(DumpWriter* writer, objArrayOop array); 640 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 641 static void dump_prim_array(DumpWriter* writer, typeArrayOop array); 642 // create HPROF_FRAME record for the given method and bci 643 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci); 644 }; 645 646 // write a header of the given type 647 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) { 648 writer->write_u1((u1)tag); 649 writer->write_u4(0); // current ticks 650 writer->write_u4(len); 651 } 652 653 // returns hprof tag for the given type signature 654 hprofTag DumperSupport::sig2tag(Symbol* sig) { 655 switch (sig->byte_at(0)) { 656 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT; 657 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT; 658 case JVM_SIGNATURE_BYTE : return HPROF_BYTE; 659 case JVM_SIGNATURE_CHAR : return HPROF_CHAR; 660 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT; 661 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE; 662 case JVM_SIGNATURE_INT : return HPROF_INT; 663 case JVM_SIGNATURE_LONG : return HPROF_LONG; 664 case JVM_SIGNATURE_SHORT : return HPROF_SHORT; 665 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN; 666 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 667 } 668 } 669 670 hprofTag DumperSupport::type2tag(BasicType type) { 671 switch (type) { 672 case T_BYTE : return HPROF_BYTE; 673 case T_CHAR : return HPROF_CHAR; 674 case T_FLOAT : return HPROF_FLOAT; 675 case T_DOUBLE : return HPROF_DOUBLE; 676 case T_INT : return HPROF_INT; 677 case T_LONG : return HPROF_LONG; 678 case T_SHORT : return HPROF_SHORT; 679 case T_BOOLEAN : return HPROF_BOOLEAN; 680 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE; 681 } 682 } 683 684 // dump a jfloat 685 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) { 686 if (g_isnan(f)) { 687 writer->write_u4(0x7fc00000); // collapsing NaNs 688 } else { 689 union { 690 int i; 691 float f; 692 } u; 693 u.f = (float)f; 694 writer->write_u4((u4)u.i); 695 } 696 } 697 698 // dump a jdouble 699 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) { 700 union { 701 jlong l; 702 double d; 703 } u; 704 if (g_isnan(d)) { // collapsing NaNs 705 u.l = (jlong)(0x7ff80000); 706 u.l = (u.l << 32); 707 } else { 708 u.d = (double)d; 709 } 710 writer->write_u8((u8)u.l); 711 } 712 713 // dumps the raw value of the given field 714 void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) { 715 switch (type) { 716 case JVM_SIGNATURE_CLASS : 717 case JVM_SIGNATURE_ARRAY : { 718 oop o; 719 if (UseCompressedOops) { 720 o = oopDesc::load_decode_heap_oop((narrowOop*)addr); 721 } else { 722 o = oopDesc::load_decode_heap_oop((oop*)addr); 723 } 724 725 // reflection and sun.misc.Unsafe classes may have a reference to a 726 // Klass* so filter it out. 727 assert(o->is_oop_or_null(), "should always be an oop"); 728 writer->write_objectID(o); 729 break; 730 } 731 case JVM_SIGNATURE_BYTE : { 732 jbyte* b = (jbyte*)addr; 733 writer->write_u1((u1)*b); 734 break; 735 } 736 case JVM_SIGNATURE_CHAR : { 737 jchar* c = (jchar*)addr; 738 writer->write_u2((u2)*c); 739 break; 740 } 741 case JVM_SIGNATURE_SHORT : { 742 jshort* s = (jshort*)addr; 743 writer->write_u2((u2)*s); 744 break; 745 } 746 case JVM_SIGNATURE_FLOAT : { 747 jfloat* f = (jfloat*)addr; 748 dump_float(writer, *f); 749 break; 750 } 751 case JVM_SIGNATURE_DOUBLE : { 752 jdouble* f = (jdouble*)addr; 753 dump_double(writer, *f); 754 break; 755 } 756 case JVM_SIGNATURE_INT : { 757 jint* i = (jint*)addr; 758 writer->write_u4((u4)*i); 759 break; 760 } 761 case JVM_SIGNATURE_LONG : { 762 jlong* l = (jlong*)addr; 763 writer->write_u8((u8)*l); 764 break; 765 } 766 case JVM_SIGNATURE_BOOLEAN : { 767 jboolean* b = (jboolean*)addr; 768 writer->write_u1((u1)*b); 769 break; 770 } 771 default : ShouldNotReachHere(); 772 } 773 } 774 775 // returns the size of the instance of the given class 776 u4 DumperSupport::instance_size(Klass* k) { 777 HandleMark hm; 778 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 779 780 u4 size = 0; 781 782 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { 783 if (!fld.access_flags().is_static()) { 784 Symbol* sig = fld.signature(); 785 switch (sig->byte_at(0)) { 786 case JVM_SIGNATURE_CLASS : 787 case JVM_SIGNATURE_ARRAY : size += oopSize; break; 788 789 case JVM_SIGNATURE_BYTE : 790 case JVM_SIGNATURE_BOOLEAN : size += 1; break; 791 792 case JVM_SIGNATURE_CHAR : 793 case JVM_SIGNATURE_SHORT : size += 2; break; 794 795 case JVM_SIGNATURE_INT : 796 case JVM_SIGNATURE_FLOAT : size += 4; break; 797 798 case JVM_SIGNATURE_LONG : 799 case JVM_SIGNATURE_DOUBLE : size += 8; break; 800 801 default : ShouldNotReachHere(); 802 } 803 } 804 } 805 return size; 806 } 807 808 // dumps static fields of the given class 809 void DumperSupport::dump_static_fields(DumpWriter* writer, Klass* k) { 810 HandleMark hm; 811 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 812 813 // pass 1 - count the static fields 814 u2 field_count = 0; 815 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { 816 if (fldc.access_flags().is_static()) field_count++; 817 } 818 // Add in resolved_references which is referenced by the cpCache 819 // The resolved_references is an array per InstanceKlass holding the 820 // strings and other oops resolved from the constant pool. 821 oop resolved_references = ikh->constants()->resolved_references_or_null(); 822 if (resolved_references != NULL) { 823 field_count++; 824 825 // Add in the resolved_references of the used previous versions of the class 826 // in the case of RedefineClasses 827 InstanceKlass* prev = ikh->previous_versions(); 828 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) { 829 field_count++; 830 prev = prev->previous_versions(); 831 } 832 } 833 834 // Also provide a pointer to the init_lock if present, so there aren't unreferenced int[0] 835 // arrays. 836 oop init_lock = ikh->init_lock(); 837 if (init_lock != NULL) { 838 field_count++; 839 } 840 841 writer->write_u2(field_count); 842 843 // pass 2 - dump the field descriptors and raw values 844 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { 845 if (fld.access_flags().is_static()) { 846 Symbol* sig = fld.signature(); 847 848 writer->write_symbolID(fld.name()); // name 849 writer->write_u1(sig2tag(sig)); // type 850 851 // value 852 int offset = fld.offset(); 853 address addr = (address)ikh->java_mirror() + offset; 854 855 dump_field_value(writer, sig->byte_at(0), addr); 856 } 857 } 858 859 // Add resolved_references for each class that has them 860 if (resolved_references != NULL) { 861 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 862 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 863 writer->write_objectID(resolved_references); 864 865 // Also write any previous versions 866 InstanceKlass* prev = ikh->previous_versions(); 867 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) { 868 writer->write_symbolID(vmSymbols::resolved_references_name()); // name 869 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type 870 writer->write_objectID(prev->constants()->resolved_references()); 871 prev = prev->previous_versions(); 872 } 873 } 874 875 // Add init lock to the end if the class is not yet initialized 876 if (init_lock != NULL) { 877 writer->write_symbolID(vmSymbols::init_lock_name()); // name 878 writer->write_u1(sig2tag(vmSymbols::int_array_signature())); // type 879 writer->write_objectID(init_lock); 880 } 881 } 882 883 // dump the raw values of the instance fields of the given object 884 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) { 885 HandleMark hm; 886 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass()); 887 888 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) { 889 if (!fld.access_flags().is_static()) { 890 Symbol* sig = fld.signature(); 891 address addr = (address)o + fld.offset(); 892 893 dump_field_value(writer, sig->byte_at(0), addr); 894 } 895 } 896 } 897 898 // dumps the definition of the instance fields for a given class 899 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, Klass* k) { 900 HandleMark hm; 901 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k); 902 903 // pass 1 - count the instance fields 904 u2 field_count = 0; 905 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) { 906 if (!fldc.access_flags().is_static()) field_count++; 907 } 908 909 writer->write_u2(field_count); 910 911 // pass 2 - dump the field descriptors 912 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) { 913 if (!fld.access_flags().is_static()) { 914 Symbol* sig = fld.signature(); 915 916 writer->write_symbolID(fld.name()); // name 917 writer->write_u1(sig2tag(sig)); // type 918 } 919 } 920 } 921 922 // creates HPROF_GC_INSTANCE_DUMP record for the given object 923 void DumperSupport::dump_instance(DumpWriter* writer, oop o) { 924 Klass* k = o->klass(); 925 926 writer->write_u1(HPROF_GC_INSTANCE_DUMP); 927 writer->write_objectID(o); 928 writer->write_u4(STACK_TRACE_ID); 929 930 // class ID 931 writer->write_classID(k); 932 933 // number of bytes that follow 934 writer->write_u4(instance_size(k) ); 935 936 // field values 937 dump_instance_fields(writer, o); 938 } 939 940 // creates HPROF_GC_CLASS_DUMP record for the given class and each of 941 // its array classes 942 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, Klass* k) { 943 Klass* klass = k; 944 assert(klass->oop_is_instance(), "not an InstanceKlass"); 945 InstanceKlass* ik = (InstanceKlass*)klass; 946 947 writer->write_u1(HPROF_GC_CLASS_DUMP); 948 949 // class ID 950 writer->write_classID(ik); 951 writer->write_u4(STACK_TRACE_ID); 952 953 // super class ID 954 Klass* java_super = ik->java_super(); 955 if (java_super == NULL) { 956 writer->write_objectID(oop(NULL)); 957 } else { 958 writer->write_classID(java_super); 959 } 960 961 writer->write_objectID(ik->class_loader()); 962 writer->write_objectID(ik->signers()); 963 writer->write_objectID(ik->protection_domain()); 964 965 // reserved 966 writer->write_objectID(oop(NULL)); 967 writer->write_objectID(oop(NULL)); 968 969 // instance size 970 writer->write_u4(DumperSupport::instance_size(k)); 971 972 // size of constant pool - ignored by HAT 1.1 973 writer->write_u2(0); 974 975 // number of static fields 976 dump_static_fields(writer, k); 977 978 // description of instance fields 979 dump_instance_field_descriptors(writer, k); 980 981 // array classes 982 k = klass->array_klass_or_null(); 983 while (k != NULL) { 984 Klass* klass = k; 985 assert(klass->oop_is_objArray(), "not an ObjArrayKlass"); 986 987 writer->write_u1(HPROF_GC_CLASS_DUMP); 988 writer->write_classID(klass); 989 writer->write_u4(STACK_TRACE_ID); 990 991 // super class of array classes is java.lang.Object 992 java_super = klass->java_super(); 993 assert(java_super != NULL, "checking"); 994 writer->write_classID(java_super); 995 996 writer->write_objectID(ik->class_loader()); 997 writer->write_objectID(ik->signers()); 998 writer->write_objectID(ik->protection_domain()); 999 1000 writer->write_objectID(oop(NULL)); // reserved 1001 writer->write_objectID(oop(NULL)); 1002 writer->write_u4(0); // instance size 1003 writer->write_u2(0); // constant pool 1004 writer->write_u2(0); // static fields 1005 writer->write_u2(0); // instance fields 1006 1007 // get the array class for the next rank 1008 k = klass->array_klass_or_null(); 1009 } 1010 } 1011 1012 // creates HPROF_GC_CLASS_DUMP record for a given primitive array 1013 // class (and each multi-dimensional array class too) 1014 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, Klass* k) { 1015 // array classes 1016 while (k != NULL) { 1017 Klass* klass = k; 1018 1019 writer->write_u1(HPROF_GC_CLASS_DUMP); 1020 writer->write_classID(klass); 1021 writer->write_u4(STACK_TRACE_ID); 1022 1023 // super class of array classes is java.lang.Object 1024 Klass* java_super = klass->java_super(); 1025 assert(java_super != NULL, "checking"); 1026 writer->write_classID(java_super); 1027 1028 writer->write_objectID(oop(NULL)); // loader 1029 writer->write_objectID(oop(NULL)); // signers 1030 writer->write_objectID(oop(NULL)); // protection domain 1031 1032 writer->write_objectID(oop(NULL)); // reserved 1033 writer->write_objectID(oop(NULL)); 1034 writer->write_u4(0); // instance size 1035 writer->write_u2(0); // constant pool 1036 writer->write_u2(0); // static fields 1037 writer->write_u2(0); // instance fields 1038 1039 // get the array class for the next rank 1040 k = klass->array_klass_or_null(); 1041 } 1042 } 1043 1044 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array 1045 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) { 1046 1047 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP); 1048 writer->write_objectID(array); 1049 writer->write_u4(STACK_TRACE_ID); 1050 writer->write_u4((u4)array->length()); 1051 1052 // array class ID 1053 writer->write_classID(array->klass()); 1054 1055 // [id]* elements 1056 for (int index=0; index<array->length(); index++) { 1057 oop o = array->obj_at(index); 1058 writer->write_objectID(o); 1059 } 1060 } 1061 1062 #define WRITE_ARRAY(Array, Type, Size) \ 1063 for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); } 1064 1065 1066 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array 1067 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) { 1068 BasicType type = TypeArrayKlass::cast(array->klass())->element_type(); 1069 1070 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP); 1071 writer->write_objectID(array); 1072 writer->write_u4(STACK_TRACE_ID); 1073 writer->write_u4((u4)array->length()); 1074 writer->write_u1(type2tag(type)); 1075 1076 // nothing to copy 1077 if (array->length() == 0) { 1078 return; 1079 } 1080 1081 // If the byte ordering is big endian then we can copy most types directly 1082 u4 length_in_bytes = (u4)array->length() * type2aelembytes(type); 1083 1084 switch (type) { 1085 case T_INT : { 1086 if (Bytes::is_Java_byte_ordering_different()) { 1087 WRITE_ARRAY(array, int, u4); 1088 } else { 1089 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes); 1090 } 1091 break; 1092 } 1093 case T_BYTE : { 1094 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes); 1095 break; 1096 } 1097 case T_CHAR : { 1098 if (Bytes::is_Java_byte_ordering_different()) { 1099 WRITE_ARRAY(array, char, u2); 1100 } else { 1101 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes); 1102 } 1103 break; 1104 } 1105 case T_SHORT : { 1106 if (Bytes::is_Java_byte_ordering_different()) { 1107 WRITE_ARRAY(array, short, u2); 1108 } else { 1109 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes); 1110 } 1111 break; 1112 } 1113 case T_BOOLEAN : { 1114 if (Bytes::is_Java_byte_ordering_different()) { 1115 WRITE_ARRAY(array, bool, u1); 1116 } else { 1117 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes); 1118 } 1119 break; 1120 } 1121 case T_LONG : { 1122 if (Bytes::is_Java_byte_ordering_different()) { 1123 WRITE_ARRAY(array, long, u8); 1124 } else { 1125 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes); 1126 } 1127 break; 1128 } 1129 1130 // handle float/doubles in a special value to ensure than NaNs are 1131 // written correctly. TO DO: Check if we can avoid this on processors that 1132 // use IEEE 754. 1133 1134 case T_FLOAT : { 1135 for (int i=0; i<array->length(); i++) { 1136 dump_float( writer, array->float_at(i) ); 1137 } 1138 break; 1139 } 1140 case T_DOUBLE : { 1141 for (int i=0; i<array->length(); i++) { 1142 dump_double( writer, array->double_at(i) ); 1143 } 1144 break; 1145 } 1146 default : ShouldNotReachHere(); 1147 } 1148 } 1149 1150 // create a HPROF_FRAME record of the given Method* and bci 1151 void DumperSupport::dump_stack_frame(DumpWriter* writer, 1152 int frame_serial_num, 1153 int class_serial_num, 1154 Method* m, 1155 int bci) { 1156 int line_number; 1157 if (m->is_native()) { 1158 line_number = -3; // native frame 1159 } else { 1160 line_number = m->line_number_from_bci(bci); 1161 } 1162 1163 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4)); 1164 writer->write_id(frame_serial_num); // frame serial number 1165 writer->write_symbolID(m->name()); // method's name 1166 writer->write_symbolID(m->signature()); // method's signature 1167 1168 assert(m->method_holder()->oop_is_instance(), "not InstanceKlass"); 1169 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name 1170 writer->write_u4(class_serial_num); // class serial number 1171 writer->write_u4((u4) line_number); // line number 1172 } 1173 1174 1175 // Support class used to generate HPROF_UTF8 records from the entries in the 1176 // SymbolTable. 1177 1178 class SymbolTableDumper : public SymbolClosure { 1179 private: 1180 DumpWriter* _writer; 1181 DumpWriter* writer() const { return _writer; } 1182 public: 1183 SymbolTableDumper(DumpWriter* writer) { _writer = writer; } 1184 void do_symbol(Symbol** p); 1185 }; 1186 1187 void SymbolTableDumper::do_symbol(Symbol** p) { 1188 ResourceMark rm; 1189 Symbol* sym = load_symbol(p); 1190 int len = sym->utf8_length(); 1191 if (len > 0) { 1192 char* s = sym->as_utf8(); 1193 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len); 1194 writer()->write_symbolID(sym); 1195 writer()->write_raw(s, len); 1196 } 1197 } 1198 1199 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records 1200 1201 class JNILocalsDumper : public OopClosure { 1202 private: 1203 DumpWriter* _writer; 1204 u4 _thread_serial_num; 1205 int _frame_num; 1206 DumpWriter* writer() const { return _writer; } 1207 public: 1208 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) { 1209 _writer = writer; 1210 _thread_serial_num = thread_serial_num; 1211 _frame_num = -1; // default - empty stack 1212 } 1213 void set_frame_number(int n) { _frame_num = n; } 1214 void do_oop(oop* obj_p); 1215 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1216 }; 1217 1218 1219 void JNILocalsDumper::do_oop(oop* obj_p) { 1220 // ignore null or deleted handles 1221 oop o = *obj_p; 1222 if (o != NULL && o != JNIHandles::deleted_handle()) { 1223 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL); 1224 writer()->write_objectID(o); 1225 writer()->write_u4(_thread_serial_num); 1226 writer()->write_u4((u4)_frame_num); 1227 } 1228 } 1229 1230 1231 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records 1232 1233 class JNIGlobalsDumper : public OopClosure { 1234 private: 1235 DumpWriter* _writer; 1236 DumpWriter* writer() const { return _writer; } 1237 1238 public: 1239 JNIGlobalsDumper(DumpWriter* writer) { 1240 _writer = writer; 1241 } 1242 void do_oop(oop* obj_p); 1243 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1244 }; 1245 1246 void JNIGlobalsDumper::do_oop(oop* obj_p) { 1247 oop o = *obj_p; 1248 1249 // ignore these 1250 if (o == NULL || o == JNIHandles::deleted_handle()) return; 1251 1252 // we ignore global ref to symbols and other internal objects 1253 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) { 1254 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL); 1255 writer()->write_objectID(o); 1256 writer()->write_objectID((oopDesc*)obj_p); // global ref ID 1257 } 1258 }; 1259 1260 1261 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records 1262 1263 class MonitorUsedDumper : public OopClosure { 1264 private: 1265 DumpWriter* _writer; 1266 DumpWriter* writer() const { return _writer; } 1267 public: 1268 MonitorUsedDumper(DumpWriter* writer) { 1269 _writer = writer; 1270 } 1271 void do_oop(oop* obj_p) { 1272 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED); 1273 writer()->write_objectID(*obj_p); 1274 } 1275 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); } 1276 }; 1277 1278 1279 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records 1280 1281 class StickyClassDumper : public KlassClosure { 1282 private: 1283 DumpWriter* _writer; 1284 DumpWriter* writer() const { return _writer; } 1285 public: 1286 StickyClassDumper(DumpWriter* writer) { 1287 _writer = writer; 1288 } 1289 void do_klass(Klass* k) { 1290 if (k->oop_is_instance()) { 1291 InstanceKlass* ik = InstanceKlass::cast(k); 1292 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS); 1293 writer()->write_classID(ik); 1294 } 1295 } 1296 }; 1297 1298 1299 class VM_HeapDumper; 1300 1301 // Support class using when iterating over the heap. 1302 1303 class HeapObjectDumper : public ObjectClosure { 1304 private: 1305 VM_HeapDumper* _dumper; 1306 DumpWriter* _writer; 1307 1308 VM_HeapDumper* dumper() { return _dumper; } 1309 DumpWriter* writer() { return _writer; } 1310 1311 // used to indicate that a record has been writen 1312 void mark_end_of_record(); 1313 1314 public: 1315 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) { 1316 _dumper = dumper; 1317 _writer = writer; 1318 } 1319 1320 // called for each object in the heap 1321 void do_object(oop o); 1322 }; 1323 1324 void HeapObjectDumper::do_object(oop o) { 1325 // hide the sentinel for deleted handles 1326 if (o == JNIHandles::deleted_handle()) return; 1327 1328 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records 1329 if (o->klass() == SystemDictionary::Class_klass()) { 1330 if (!java_lang_Class::is_primitive(o)) { 1331 return; 1332 } 1333 } 1334 1335 if (o->is_instance()) { 1336 // create a HPROF_GC_INSTANCE record for each object 1337 DumperSupport::dump_instance(writer(), o); 1338 mark_end_of_record(); 1339 } else if (o->is_objArray()) { 1340 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array 1341 DumperSupport::dump_object_array(writer(), objArrayOop(o)); 1342 mark_end_of_record(); 1343 } else if (o->is_typeArray()) { 1344 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array 1345 DumperSupport::dump_prim_array(writer(), typeArrayOop(o)); 1346 mark_end_of_record(); 1347 } 1348 } 1349 1350 // The VM operation that performs the heap dump 1351 class VM_HeapDumper : public VM_GC_Operation { 1352 private: 1353 static VM_HeapDumper* _global_dumper; 1354 static DumpWriter* _global_writer; 1355 DumpWriter* _local_writer; 1356 JavaThread* _oome_thread; 1357 Method* _oome_constructor; 1358 bool _gc_before_heap_dump; 1359 bool _is_segmented_dump; 1360 jlong _dump_start; 1361 GrowableArray<Klass*>* _klass_map; 1362 ThreadStackTrace** _stack_traces; 1363 int _num_threads; 1364 1365 // accessors and setters 1366 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; } 1367 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; } 1368 void set_global_dumper() { 1369 assert(_global_dumper == NULL, "Error"); 1370 _global_dumper = this; 1371 } 1372 void set_global_writer() { 1373 assert(_global_writer == NULL, "Error"); 1374 _global_writer = _local_writer; 1375 } 1376 void clear_global_dumper() { _global_dumper = NULL; } 1377 void clear_global_writer() { _global_writer = NULL; } 1378 1379 bool is_segmented_dump() const { return _is_segmented_dump; } 1380 void set_segmented_dump() { _is_segmented_dump = true; } 1381 jlong dump_start() const { return _dump_start; } 1382 void set_dump_start(jlong pos); 1383 1384 bool skip_operation() const; 1385 1386 // writes a HPROF_LOAD_CLASS record 1387 static void do_load_class(Klass* k); 1388 1389 // writes a HPROF_GC_CLASS_DUMP record for the given class 1390 // (and each array class too) 1391 static void do_class_dump(Klass* k); 1392 1393 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1394 // array (and each multi-dimensional array too) 1395 static void do_basic_type_array_class_dump(Klass* k); 1396 1397 // HPROF_GC_ROOT_THREAD_OBJ records 1398 int do_thread(JavaThread* thread, u4 thread_serial_num); 1399 void do_threads(); 1400 1401 void add_class_serial_number(Klass* k, int serial_num) { 1402 _klass_map->at_put_grow(serial_num, k); 1403 } 1404 1405 // HPROF_TRACE and HPROF_FRAME records 1406 void dump_stack_traces(); 1407 1408 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record 1409 void write_dump_header(); 1410 1411 // fixes up the length of the current dump record 1412 void write_current_dump_record_length(); 1413 1414 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END 1415 // record in the case of a segmented heap dump) 1416 void end_of_dump(); 1417 1418 public: 1419 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) : 1420 VM_GC_Operation(0 /* total collections, dummy, ignored */, 1421 GCCause::_heap_dump /* GC Cause */, 1422 0 /* total full collections, dummy, ignored */, 1423 gc_before_heap_dump) { 1424 _local_writer = writer; 1425 _gc_before_heap_dump = gc_before_heap_dump; 1426 _is_segmented_dump = false; 1427 _dump_start = (jlong)-1; 1428 _klass_map = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true); 1429 _stack_traces = NULL; 1430 _num_threads = 0; 1431 if (oome) { 1432 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread"); 1433 // get OutOfMemoryError zero-parameter constructor 1434 InstanceKlass* oome_ik = InstanceKlass::cast(SystemDictionary::OutOfMemoryError_klass()); 1435 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(), 1436 vmSymbols::void_method_signature()); 1437 // get thread throwing OOME when generating the heap dump at OOME 1438 _oome_thread = JavaThread::current(); 1439 } else { 1440 _oome_thread = NULL; 1441 _oome_constructor = NULL; 1442 } 1443 } 1444 ~VM_HeapDumper() { 1445 if (_stack_traces != NULL) { 1446 for (int i=0; i < _num_threads; i++) { 1447 delete _stack_traces[i]; 1448 } 1449 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces, mtInternal); 1450 } 1451 delete _klass_map; 1452 } 1453 1454 VMOp_Type type() const { return VMOp_HeapDumper; } 1455 // used to mark sub-record boundary 1456 void check_segment_length(); 1457 void doit(); 1458 }; 1459 1460 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL; 1461 DumpWriter* VM_HeapDumper::_global_writer = NULL; 1462 1463 bool VM_HeapDumper::skip_operation() const { 1464 return false; 1465 } 1466 1467 // sets the dump starting position 1468 void VM_HeapDumper::set_dump_start(jlong pos) { 1469 _dump_start = pos; 1470 } 1471 1472 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record 1473 void VM_HeapDumper::write_dump_header() { 1474 if (writer()->is_open()) { 1475 if (is_segmented_dump()) { 1476 writer()->write_u1(HPROF_HEAP_DUMP_SEGMENT); 1477 } else { 1478 writer()->write_u1(HPROF_HEAP_DUMP); 1479 } 1480 writer()->write_u4(0); // current ticks 1481 1482 // record the starting position for the dump (its length will be fixed up later) 1483 set_dump_start(writer()->current_offset()); 1484 writer()->write_u4(0); 1485 } 1486 } 1487 1488 // fixes up the length of the current dump record 1489 void VM_HeapDumper::write_current_dump_record_length() { 1490 if (writer()->is_open()) { 1491 assert(dump_start() >= 0, "no dump start recorded"); 1492 1493 // calculate the size of the dump record 1494 julong dump_end = writer()->current_offset(); 1495 julong dump_len = (dump_end - dump_start() - 4); 1496 1497 // record length must fit in a u4 1498 if (dump_len > max_juint) { 1499 warning("record is too large"); 1500 } 1501 1502 // seek to the dump start and fix-up the length 1503 writer()->seek_to_offset(dump_start()); 1504 writer()->write_u4((u4)dump_len); 1505 1506 // adjust the total size written to keep the bytes written correct. 1507 writer()->adjust_bytes_written(-((jlong) sizeof(u4))); 1508 1509 // seek to dump end so we can continue 1510 writer()->seek_to_offset(dump_end); 1511 1512 // no current dump record 1513 set_dump_start((jlong)-1); 1514 } 1515 } 1516 1517 // used on a sub-record boundary to check if we need to start a 1518 // new segment. 1519 void VM_HeapDumper::check_segment_length() { 1520 if (writer()->is_open()) { 1521 if (is_segmented_dump()) { 1522 // don't use current_offset that would be too expensive on a per record basis 1523 julong dump_end = writer()->bytes_written() + writer()->bytes_unwritten(); 1524 assert(dump_end == (julong)writer()->current_offset(), "checking"); 1525 julong dump_len = (dump_end - dump_start() - 4); 1526 assert(dump_len <= max_juint, "bad dump length"); 1527 1528 if (dump_len > HeapDumpSegmentSize) { 1529 write_current_dump_record_length(); 1530 write_dump_header(); 1531 } 1532 } 1533 } 1534 } 1535 1536 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END 1537 // record in the case of a segmented heap dump) 1538 void VM_HeapDumper::end_of_dump() { 1539 if (writer()->is_open()) { 1540 write_current_dump_record_length(); 1541 1542 // for segmented dump we write the end record 1543 if (is_segmented_dump()) { 1544 writer()->write_u1(HPROF_HEAP_DUMP_END); 1545 writer()->write_u4(0); 1546 writer()->write_u4(0); 1547 } 1548 } 1549 } 1550 1551 // marks sub-record boundary 1552 void HeapObjectDumper::mark_end_of_record() { 1553 dumper()->check_segment_length(); 1554 } 1555 1556 // writes a HPROF_LOAD_CLASS record for the class (and each of its 1557 // array classes) 1558 void VM_HeapDumper::do_load_class(Klass* k) { 1559 static u4 class_serial_num = 0; 1560 1561 // len of HPROF_LOAD_CLASS record 1562 u4 remaining = 2*oopSize + 2*sizeof(u4); 1563 1564 // write a HPROF_LOAD_CLASS for the class and each array class 1565 do { 1566 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining); 1567 1568 // class serial number is just a number 1569 writer()->write_u4(++class_serial_num); 1570 1571 // class ID 1572 Klass* klass = k; 1573 writer()->write_classID(klass); 1574 1575 // add the Klass* and class serial number pair 1576 dumper()->add_class_serial_number(klass, class_serial_num); 1577 1578 writer()->write_u4(STACK_TRACE_ID); 1579 1580 // class name ID 1581 Symbol* name = klass->name(); 1582 writer()->write_symbolID(name); 1583 1584 // write a LOAD_CLASS record for the array type (if it exists) 1585 k = klass->array_klass_or_null(); 1586 } while (k != NULL); 1587 } 1588 1589 // writes a HPROF_GC_CLASS_DUMP record for the given class 1590 void VM_HeapDumper::do_class_dump(Klass* k) { 1591 if (k->oop_is_instance()) { 1592 DumperSupport::dump_class_and_array_classes(writer(), k); 1593 } 1594 } 1595 1596 // writes a HPROF_GC_CLASS_DUMP records for a given basic type 1597 // array (and each multi-dimensional array too) 1598 void VM_HeapDumper::do_basic_type_array_class_dump(Klass* k) { 1599 DumperSupport::dump_basic_type_array_class(writer(), k); 1600 } 1601 1602 // Walk the stack of the given thread. 1603 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local 1604 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local 1605 // 1606 // It returns the number of Java frames in this thread stack 1607 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) { 1608 JNILocalsDumper blk(writer(), thread_serial_num); 1609 1610 oop threadObj = java_thread->threadObj(); 1611 assert(threadObj != NULL, "sanity check"); 1612 1613 int stack_depth = 0; 1614 if (java_thread->has_last_Java_frame()) { 1615 1616 // vframes are resource allocated 1617 Thread* current_thread = Thread::current(); 1618 ResourceMark rm(current_thread); 1619 HandleMark hm(current_thread); 1620 1621 RegisterMap reg_map(java_thread); 1622 frame f = java_thread->last_frame(); 1623 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread); 1624 frame* last_entry_frame = NULL; 1625 int extra_frames = 0; 1626 1627 if (java_thread == _oome_thread && _oome_constructor != NULL) { 1628 extra_frames++; 1629 } 1630 while (vf != NULL) { 1631 blk.set_frame_number(stack_depth); 1632 if (vf->is_java_frame()) { 1633 1634 // java frame (interpreted, compiled, ...) 1635 javaVFrame *jvf = javaVFrame::cast(vf); 1636 if (!(jvf->method()->is_native())) { 1637 StackValueCollection* locals = jvf->locals(); 1638 for (int slot=0; slot<locals->size(); slot++) { 1639 if (locals->at(slot)->type() == T_OBJECT) { 1640 oop o = locals->obj_at(slot)(); 1641 1642 if (o != NULL) { 1643 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME); 1644 writer()->write_objectID(o); 1645 writer()->write_u4(thread_serial_num); 1646 writer()->write_u4((u4) (stack_depth + extra_frames)); 1647 } 1648 } 1649 } 1650 } else { 1651 // native frame 1652 if (stack_depth == 0) { 1653 // JNI locals for the top frame. 1654 java_thread->active_handles()->oops_do(&blk); 1655 } else { 1656 if (last_entry_frame != NULL) { 1657 // JNI locals for the entry frame 1658 assert(last_entry_frame->is_entry_frame(), "checking"); 1659 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk); 1660 } 1661 } 1662 } 1663 // increment only for Java frames 1664 stack_depth++; 1665 last_entry_frame = NULL; 1666 1667 } else { 1668 // externalVFrame - if it's an entry frame then report any JNI locals 1669 // as roots when we find the corresponding native javaVFrame 1670 frame* fr = vf->frame_pointer(); 1671 assert(fr != NULL, "sanity check"); 1672 if (fr->is_entry_frame()) { 1673 last_entry_frame = fr; 1674 } 1675 } 1676 vf = vf->sender(); 1677 } 1678 } else { 1679 // no last java frame but there may be JNI locals 1680 java_thread->active_handles()->oops_do(&blk); 1681 } 1682 return stack_depth; 1683 } 1684 1685 1686 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk 1687 // the stack so that locals and JNI locals are dumped. 1688 void VM_HeapDumper::do_threads() { 1689 for (int i=0; i < _num_threads; i++) { 1690 JavaThread* thread = _stack_traces[i]->thread(); 1691 oop threadObj = thread->threadObj(); 1692 u4 thread_serial_num = i+1; 1693 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID; 1694 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ); 1695 writer()->write_objectID(threadObj); 1696 writer()->write_u4(thread_serial_num); // thread number 1697 writer()->write_u4(stack_serial_num); // stack trace serial number 1698 int num_frames = do_thread(thread, thread_serial_num); 1699 assert(num_frames == _stack_traces[i]->get_stack_depth(), 1700 "total number of Java frames not matched"); 1701 } 1702 } 1703 1704 1705 // The VM operation that dumps the heap. The dump consists of the following 1706 // records: 1707 // 1708 // HPROF_HEADER 1709 // [HPROF_UTF8]* 1710 // [HPROF_LOAD_CLASS]* 1711 // [[HPROF_FRAME]*|HPROF_TRACE]* 1712 // [HPROF_GC_CLASS_DUMP]* 1713 // HPROF_HEAP_DUMP 1714 // 1715 // The HPROF_TRACE records represent the stack traces where the heap dump 1716 // is generated and a "dummy trace" record which does not include 1717 // any frames. The dummy trace record is used to be referenced as the 1718 // unknown object alloc site. 1719 // 1720 // The HPROF_HEAP_DUMP record has a length following by sub-records. To allow 1721 // the heap dump be generated in a single pass we remember the position of 1722 // the dump length and fix it up after all sub-records have been written. 1723 // To generate the sub-records we iterate over the heap, writing 1724 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP 1725 // records as we go. Once that is done we write records for some of the GC 1726 // roots. 1727 1728 void VM_HeapDumper::doit() { 1729 1730 HandleMark hm; 1731 CollectedHeap* ch = Universe::heap(); 1732 1733 ch->ensure_parsability(false); // must happen, even if collection does 1734 // not happen (e.g. due to GC_locker) 1735 1736 if (_gc_before_heap_dump) { 1737 if (GC_locker::is_active()) { 1738 warning("GC locker is held; pre-heapdump GC was skipped"); 1739 } else { 1740 ch->collect_as_vm_thread(GCCause::_heap_dump); 1741 } 1742 } 1743 1744 // At this point we should be the only dumper active, so 1745 // the following should be safe. 1746 set_global_dumper(); 1747 set_global_writer(); 1748 1749 // Write the file header - use 1.0.2 for large heaps, otherwise 1.0.1 1750 size_t used = ch->used(); 1751 const char* header; 1752 if (used > (size_t)SegmentedHeapDumpThreshold) { 1753 set_segmented_dump(); 1754 header = "JAVA PROFILE 1.0.2"; 1755 } else { 1756 header = "JAVA PROFILE 1.0.1"; 1757 } 1758 1759 // header is few bytes long - no chance to overflow int 1760 writer()->write_raw((void*)header, (int)strlen(header)); 1761 writer()->write_u1(0); // terminator 1762 writer()->write_u4(oopSize); 1763 writer()->write_u8(os::javaTimeMillis()); 1764 1765 // HPROF_UTF8 records 1766 SymbolTableDumper sym_dumper(writer()); 1767 SymbolTable::symbols_do(&sym_dumper); 1768 1769 // write HPROF_LOAD_CLASS records 1770 ClassLoaderDataGraph::classes_do(&do_load_class); 1771 Universe::basic_type_classes_do(&do_load_class); 1772 1773 // write HPROF_FRAME and HPROF_TRACE records 1774 // this must be called after _klass_map is built when iterating the classes above. 1775 dump_stack_traces(); 1776 1777 // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT 1778 write_dump_header(); 1779 1780 // Writes HPROF_GC_CLASS_DUMP records 1781 ClassLoaderDataGraph::classes_do(&do_class_dump); 1782 Universe::basic_type_classes_do(&do_basic_type_array_class_dump); 1783 check_segment_length(); 1784 1785 // writes HPROF_GC_INSTANCE_DUMP records. 1786 // After each sub-record is written check_segment_length will be invoked. When 1787 // generated a segmented heap dump this allows us to check if the current 1788 // segment exceeds a threshold and if so, then a new segment is started. 1789 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk 1790 // of the heap dump. 1791 HeapObjectDumper obj_dumper(this, writer()); 1792 Universe::heap()->safe_object_iterate(&obj_dumper); 1793 1794 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals 1795 do_threads(); 1796 check_segment_length(); 1797 1798 // HPROF_GC_ROOT_MONITOR_USED 1799 MonitorUsedDumper mon_dumper(writer()); 1800 ObjectSynchronizer::oops_do(&mon_dumper); 1801 check_segment_length(); 1802 1803 // HPROF_GC_ROOT_JNI_GLOBAL 1804 JNIGlobalsDumper jni_dumper(writer()); 1805 JNIHandles::oops_do(&jni_dumper); 1806 Universe::oops_do(&jni_dumper); // technically not jni roots, but global roots 1807 // for things like preallocated throwable backtraces 1808 check_segment_length(); 1809 1810 // HPROF_GC_ROOT_STICKY_CLASS 1811 StickyClassDumper class_dumper(writer()); 1812 SystemDictionary::always_strong_classes_do(&class_dumper); 1813 1814 // fixes up the length of the dump record. In the case of a segmented 1815 // heap then the HPROF_HEAP_DUMP_END record is also written. 1816 end_of_dump(); 1817 1818 // Now we clear the global variables, so that a future dumper might run. 1819 clear_global_dumper(); 1820 clear_global_writer(); 1821 } 1822 1823 void VM_HeapDumper::dump_stack_traces() { 1824 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites 1825 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4)); 1826 writer()->write_u4((u4) STACK_TRACE_ID); 1827 writer()->write_u4(0); // thread number 1828 writer()->write_u4(0); // frame count 1829 1830 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal); 1831 int frame_serial_num = 0; 1832 for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) { 1833 oop threadObj = thread->threadObj(); 1834 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) { 1835 // dump thread stack trace 1836 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false); 1837 stack_trace->dump_stack_at_safepoint(-1); 1838 _stack_traces[_num_threads++] = stack_trace; 1839 1840 // write HPROF_FRAME records for this thread's stack trace 1841 int depth = stack_trace->get_stack_depth(); 1842 int thread_frame_start = frame_serial_num; 1843 int extra_frames = 0; 1844 // write fake frame that makes it look like the thread, which caused OOME, 1845 // is in the OutOfMemoryError zero-parameter constructor 1846 if (thread == _oome_thread && _oome_constructor != NULL) { 1847 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder()); 1848 // the class serial number starts from 1 1849 assert(oome_serial_num > 0, "OutOfMemoryError class not found"); 1850 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num, 1851 _oome_constructor, 0); 1852 extra_frames++; 1853 } 1854 for (int j=0; j < depth; j++) { 1855 StackFrameInfo* frame = stack_trace->stack_frame_at(j); 1856 Method* m = frame->method(); 1857 int class_serial_num = _klass_map->find(m->method_holder()); 1858 // the class serial number starts from 1 1859 assert(class_serial_num > 0, "class not found"); 1860 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci()); 1861 } 1862 depth += extra_frames; 1863 1864 // write HPROF_TRACE record for one thread 1865 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize); 1866 int stack_serial_num = _num_threads + STACK_TRACE_ID; 1867 writer()->write_u4(stack_serial_num); // stack trace serial number 1868 writer()->write_u4((u4) _num_threads); // thread serial number 1869 writer()->write_u4(depth); // frame count 1870 for (int j=1; j <= depth; j++) { 1871 writer()->write_id(thread_frame_start + j); 1872 } 1873 } 1874 } 1875 } 1876 1877 // dump the heap to given path. 1878 PRAGMA_FORMAT_NONLITERAL_IGNORED_EXTERNAL 1879 int HeapDumper::dump(const char* path) { 1880 assert(path != NULL && strlen(path) > 0, "path missing"); 1881 1882 // print message in interactive case 1883 if (print_to_tty()) { 1884 tty->print_cr("Dumping heap to %s ...", path); 1885 timer()->start(); 1886 } 1887 1888 // create the dump writer. If the file can be opened then bail 1889 DumpWriter writer(path); 1890 if (!writer.is_open()) { 1891 set_error(writer.error()); 1892 if (print_to_tty()) { 1893 tty->print_cr("Unable to create %s: %s", path, 1894 (error() != NULL) ? error() : "reason unknown"); 1895 } 1896 return -1; 1897 } 1898 1899 // generate the dump 1900 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome); 1901 if (Thread::current()->is_VM_thread()) { 1902 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint"); 1903 dumper.doit(); 1904 } else { 1905 VMThread::execute(&dumper); 1906 } 1907 1908 // close dump file and record any error that the writer may have encountered 1909 writer.close(); 1910 set_error(writer.error()); 1911 1912 // print message in interactive case 1913 if (print_to_tty()) { 1914 timer()->stop(); 1915 if (error() == NULL) { 1916 tty->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]", 1917 writer.bytes_written(), timer()->seconds()); 1918 } else { 1919 tty->print_cr("Dump file is incomplete: %s", writer.error()); 1920 } 1921 } 1922 1923 return (writer.error() == NULL) ? 0 : -1; 1924 } 1925 1926 // stop timer (if still active), and free any error string we might be holding 1927 HeapDumper::~HeapDumper() { 1928 if (timer()->is_active()) { 1929 timer()->stop(); 1930 } 1931 set_error(NULL); 1932 } 1933 1934 1935 // returns the error string (resource allocated), or NULL 1936 char* HeapDumper::error_as_C_string() const { 1937 if (error() != NULL) { 1938 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1); 1939 strcpy(str, error()); 1940 return str; 1941 } else { 1942 return NULL; 1943 } 1944 } 1945 1946 // set the error string 1947 void HeapDumper::set_error(char* error) { 1948 if (_error != NULL) { 1949 os::free(_error); 1950 } 1951 if (error == NULL) { 1952 _error = NULL; 1953 } else { 1954 _error = os::strdup(error); 1955 assert(_error != NULL, "allocation failure"); 1956 } 1957 } 1958 1959 // Called by out-of-memory error reporting by a single Java thread 1960 // outside of a JVM safepoint 1961 void HeapDumper::dump_heap_from_oome() { 1962 HeapDumper::dump_heap(true); 1963 } 1964 1965 // Called by error reporting by a single Java thread outside of a JVM safepoint, 1966 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various 1967 // callers are strictly serialized and guaranteed not to interfere below. For more 1968 // general use, however, this method will need modification to prevent 1969 // inteference when updating the static variables base_path and dump_file_seq below. 1970 void HeapDumper::dump_heap() { 1971 HeapDumper::dump_heap(false); 1972 } 1973 1974 void HeapDumper::dump_heap(bool oome) { 1975 static char base_path[JVM_MAXPATHLEN] = {'\0'}; 1976 static uint dump_file_seq = 0; 1977 char* my_path; 1978 const int max_digit_chars = 20; 1979 1980 const char* dump_file_name = "java_pid"; 1981 const char* dump_file_ext = ".hprof"; 1982 1983 // The dump file defaults to java_pid<pid>.hprof in the current working 1984 // directory. HeapDumpPath=<file> can be used to specify an alternative 1985 // dump file name or a directory where dump file is created. 1986 if (dump_file_seq == 0) { // first time in, we initialize base_path 1987 // Calculate potentially longest base path and check if we have enough 1988 // allocated statically. 1989 const size_t total_length = 1990 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) + 1991 strlen(os::file_separator()) + max_digit_chars + 1992 strlen(dump_file_name) + strlen(dump_file_ext) + 1; 1993 if (total_length > sizeof(base_path)) { 1994 warning("Cannot create heap dump file. HeapDumpPath is too long."); 1995 return; 1996 } 1997 1998 bool use_default_filename = true; 1999 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') { 2000 // HeapDumpPath=<file> not specified 2001 } else { 2002 strncpy(base_path, HeapDumpPath, sizeof(base_path)); 2003 // check if the path is a directory (must exist) 2004 DIR* dir = os::opendir(base_path); 2005 if (dir == NULL) { 2006 use_default_filename = false; 2007 } else { 2008 // HeapDumpPath specified a directory. We append a file separator 2009 // (if needed). 2010 os::closedir(dir); 2011 size_t fs_len = strlen(os::file_separator()); 2012 if (strlen(base_path) >= fs_len) { 2013 char* end = base_path; 2014 end += (strlen(base_path) - fs_len); 2015 if (strcmp(end, os::file_separator()) != 0) { 2016 strcat(base_path, os::file_separator()); 2017 } 2018 } 2019 } 2020 } 2021 // If HeapDumpPath wasn't a file name then we append the default name 2022 if (use_default_filename) { 2023 const size_t dlen = strlen(base_path); // if heap dump dir specified 2024 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s", 2025 dump_file_name, os::current_process_id(), dump_file_ext); 2026 } 2027 const size_t len = strlen(base_path) + 1; 2028 my_path = (char*)os::malloc(len, mtInternal); 2029 if (my_path == NULL) { 2030 warning("Cannot create heap dump file. Out of system memory."); 2031 return; 2032 } 2033 strncpy(my_path, base_path, len); 2034 } else { 2035 // Append a sequence number id for dumps following the first 2036 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0 2037 my_path = (char*)os::malloc(len, mtInternal); 2038 if (my_path == NULL) { 2039 warning("Cannot create heap dump file. Out of system memory."); 2040 return; 2041 } 2042 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq); 2043 } 2044 dump_file_seq++; // increment seq number for next time we dump 2045 2046 HeapDumper dumper(false /* no GC before heap dump */, 2047 true /* send to tty */, 2048 oome /* pass along out-of-memory-error flag */); 2049 dumper.dump(my_path); 2050 os::free(my_path); 2051 }