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_symbolID(Symbol* o);
429 void write_classID(Klass* k);
430 void write_id(u4 x);
431 };
432
433 DumpWriter::DumpWriter(const char* path) {
434 // try to allocate an I/O buffer of io_buffer_size. If there isn't
435 // sufficient memory then reduce size until we can allocate something.
436 _size = io_buffer_size;
437 do {
438 _buffer = (char*)os::malloc(_size);
439 if (_buffer == NULL) {
440 _size = _size >> 1;
441 }
442 } while (_buffer == NULL && _size > 0);
443 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check");
444 _pos = 0;
445 _error = NULL;
446 _bytes_written = 0L;
447 _fd = os::create_binary_file(path, false); // don't replace existing file
448
449 // if the open failed we record the error
450 if (_fd < 0) {
451 _error = (char*)os::strdup(strerror(errno));
452 }
453 }
454
455 DumpWriter::~DumpWriter() {
456 // flush and close dump file
457 if (is_open()) {
458 close();
459 }
460 if (_buffer != NULL) os::free(_buffer);
461 if (_error != NULL) os::free(_error);
462 }
463
464 // closes dump file (if open)
465 void DumpWriter::close() {
466 // flush and close dump file
467 if (is_open()) {
468 flush();
469 ::close(file_descriptor());
470 set_file_descriptor(-1);
471 }
472 }
473
474 // write directly to the file
475 void DumpWriter::write_internal(void* s, int len) {
476 if (is_open()) {
477 int n = ::write(file_descriptor(), s, len);
478 if (n > 0) {
479 _bytes_written += n;
480 }
481 if (n != len) {
482 if (n < 0) {
483 set_error(strerror(errno));
484 } else {
485 set_error("file size limit");
486 }
487 ::close(file_descriptor());
488 set_file_descriptor(-1);
489 }
490 }
491 }
492
493 // write raw bytes
494 void DumpWriter::write_raw(void* s, int len) {
495 if (is_open()) {
496 // flush buffer to make toom
497 if ((position()+ len) >= buffer_size()) {
498 flush();
499 }
500
501 // buffer not available or too big to buffer it
502 if ((buffer() == NULL) || (len >= buffer_size())) {
503 write_internal(s, len);
504 } else {
505 // Should optimize this for u1/u2/u4/u8 sizes.
506 memcpy(buffer() + position(), s, len);
507 set_position(position() + len);
508 }
509 }
510 }
511
512 // flush any buffered bytes to the file
513 void DumpWriter::flush() {
514 if (is_open() && position() > 0) {
515 write_internal(buffer(), position());
516 set_position(0);
517 }
518 }
519
520
521 jlong DumpWriter::current_offset() {
522 if (is_open()) {
523 // the offset is the file offset plus whatever we have buffered
524 jlong offset = os::current_file_offset(file_descriptor());
525 assert(offset >= 0, "lseek failed");
526 return offset + (jlong)position();
527 } else {
528 return (jlong)-1;
529 }
530 }
531
532 void DumpWriter::seek_to_offset(jlong off) {
533 assert(off >= 0, "bad offset");
534
535 // need to flush before seeking
536 flush();
537
538 // may be closed due to I/O error
539 if (is_open()) {
540 jlong n = os::seek_to_file_offset(file_descriptor(), off);
541 assert(n >= 0, "lseek failed");
542 }
543 }
544
545 void DumpWriter::write_u2(u2 x) {
546 u2 v;
547 Bytes::put_Java_u2((address)&v, x);
548 write_raw((void*)&v, 2);
549 }
550
551 void DumpWriter::write_u4(u4 x) {
552 u4 v;
553 Bytes::put_Java_u4((address)&v, x);
554 write_raw((void*)&v, 4);
555 }
556
557 void DumpWriter::write_u8(u8 x) {
558 u8 v;
559 Bytes::put_Java_u8((address)&v, x);
560 write_raw((void*)&v, 8);
561 }
562
563 void DumpWriter::write_objectID(oop o) {
564 address a = (address)((uintptr_t)o);
565 #ifdef _LP64
566 write_u8((u8)a);
567 #else
568 write_u4((u4)a);
569 #endif
570 }
571
572 void DumpWriter::write_symbolID(Symbol* s) {
573 address a = (address)((uintptr_t)s);
574 #ifdef _LP64
575 write_u8((u8)a);
576 #else
577 write_u4((u4)a);
578 #endif
579 }
580
581 void DumpWriter::write_id(u4 x) {
582 #ifdef _LP64
583 write_u8((u8) x);
584 #else
585 write_u4(x);
586 #endif
587 }
588
589 // We use java mirror as the class ID
590 void DumpWriter::write_classID(Klass* k) {
591 write_objectID(k->java_mirror());
592 }
593
594
595
596 // Support class with a collection of functions used when dumping the heap
597
598 class DumperSupport : AllStatic {
599 public:
600
601 // write a header of the given type
602 static void write_header(DumpWriter* writer, hprofTag tag, u4 len);
603
604 // returns hprof tag for the given type signature
605 static hprofTag sig2tag(Symbol* sig);
606 // returns hprof tag for the given basic type
607 static hprofTag type2tag(BasicType type);
608
609 // returns the size of the instance of the given class
610 static u4 instance_size(klassOop k);
611
612 // dump a jfloat
613 static void dump_float(DumpWriter* writer, jfloat f);
614 // dump a jdouble
615 static void dump_double(DumpWriter* writer, jdouble d);
616 // dumps the raw value of the given field
617 static void dump_field_value(DumpWriter* writer, char type, address addr);
618 // dumps static fields of the given class
619 static void dump_static_fields(DumpWriter* writer, klassOop k);
620 // dump the raw values of the instance fields of the given object
621 static void dump_instance_fields(DumpWriter* writer, oop o);
622 // dumps the definition of the instance fields for a given class
623 static void dump_instance_field_descriptors(DumpWriter* writer, klassOop k);
624 // creates HPROF_GC_INSTANCE_DUMP record for the given object
625 static void dump_instance(DumpWriter* writer, oop o);
626 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its
627 // array classes
628 static void dump_class_and_array_classes(DumpWriter* writer, klassOop k);
629 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
630 // class (and each multi-dimensional array class too)
631 static void dump_basic_type_array_class(DumpWriter* writer, klassOop k);
632
633 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
634 static void dump_object_array(DumpWriter* writer, objArrayOop array);
635 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
636 static void dump_prim_array(DumpWriter* writer, typeArrayOop array);
637 // create HPROF_FRAME record for the given method and bci
638 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, methodOop m, int bci);
639 };
640
641 // write a header of the given type
642 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) {
643 writer->write_u1((u1)tag);
644 writer->write_u4(0); // current ticks
645 writer->write_u4(len);
646 }
647
648 // returns hprof tag for the given type signature
649 hprofTag DumperSupport::sig2tag(Symbol* sig) {
650 switch (sig->byte_at(0)) {
651 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT;
652 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT;
653 case JVM_SIGNATURE_BYTE : return HPROF_BYTE;
654 case JVM_SIGNATURE_CHAR : return HPROF_CHAR;
655 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT;
656 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE;
657 case JVM_SIGNATURE_INT : return HPROF_INT;
658 case JVM_SIGNATURE_LONG : return HPROF_LONG;
659 case JVM_SIGNATURE_SHORT : return HPROF_SHORT;
660 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN;
661 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
662 }
663 }
664
665 hprofTag DumperSupport::type2tag(BasicType type) {
666 switch (type) {
667 case T_BYTE : return HPROF_BYTE;
668 case T_CHAR : return HPROF_CHAR;
669 case T_FLOAT : return HPROF_FLOAT;
670 case T_DOUBLE : return HPROF_DOUBLE;
671 case T_INT : return HPROF_INT;
672 case T_LONG : return HPROF_LONG;
673 case T_SHORT : return HPROF_SHORT;
674 case T_BOOLEAN : return HPROF_BOOLEAN;
675 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
676 }
677 }
678
679 // dump a jfloat
680 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) {
681 if (g_isnan(f)) {
682 writer->write_u4(0x7fc00000); // collapsing NaNs
683 } else {
684 union {
685 int i;
686 float f;
687 } u;
688 u.f = (float)f;
689 writer->write_u4((u4)u.i);
690 }
691 }
692
693 // dump a jdouble
694 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) {
695 union {
696 jlong l;
697 double d;
698 } u;
699 if (g_isnan(d)) { // collapsing NaNs
700 u.l = (jlong)(0x7ff80000);
701 u.l = (u.l << 32);
702 } else {
703 u.d = (double)d;
704 }
705 writer->write_u8((u8)u.l);
706 }
707
708 // dumps the raw value of the given field
709 void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) {
710 switch (type) {
711 case JVM_SIGNATURE_CLASS :
712 case JVM_SIGNATURE_ARRAY : {
713 oop o;
714 if (UseCompressedOops) {
715 o = oopDesc::load_decode_heap_oop((narrowOop*)addr);
716 } else {
717 o = oopDesc::load_decode_heap_oop((oop*)addr);
718 }
719
720 // reflection and sun.misc.Unsafe classes may have a reference to a
721 // klassOop so filter it out.
722 if (o != NULL && o->is_klass()) {
723 o = NULL;
724 }
725
726 // FIXME: When sharing is enabled we don't emit field references to objects
727 // in shared spaces. We can remove this once we write records for the classes
728 // and strings that are shared.
729 if (o != NULL && o->is_shared()) {
730 o = NULL;
731 }
732 writer->write_objectID(o);
733 break;
734 }
735 case JVM_SIGNATURE_BYTE : {
736 jbyte* b = (jbyte*)addr;
737 writer->write_u1((u1)*b);
738 break;
739 }
740 case JVM_SIGNATURE_CHAR : {
741 jchar* c = (jchar*)addr;
742 writer->write_u2((u2)*c);
743 break;
744 }
745 case JVM_SIGNATURE_SHORT : {
746 jshort* s = (jshort*)addr;
747 writer->write_u2((u2)*s);
748 break;
749 }
750 case JVM_SIGNATURE_FLOAT : {
751 jfloat* f = (jfloat*)addr;
752 dump_float(writer, *f);
753 break;
754 }
755 case JVM_SIGNATURE_DOUBLE : {
756 jdouble* f = (jdouble*)addr;
757 dump_double(writer, *f);
758 break;
759 }
760 case JVM_SIGNATURE_INT : {
761 jint* i = (jint*)addr;
762 writer->write_u4((u4)*i);
763 break;
764 }
765 case JVM_SIGNATURE_LONG : {
766 jlong* l = (jlong*)addr;
767 writer->write_u8((u8)*l);
768 break;
769 }
770 case JVM_SIGNATURE_BOOLEAN : {
771 jboolean* b = (jboolean*)addr;
772 writer->write_u1((u1)*b);
773 break;
774 }
775 default : ShouldNotReachHere();
776 }
777 }
778
779 // returns the size of the instance of the given class
780 u4 DumperSupport::instance_size(klassOop k) {
781 HandleMark hm;
782 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
783
784 int size = 0;
785
786 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
787 if (!fld.access_flags().is_static()) {
788 Symbol* sig = fld.signature();
789 switch (sig->byte_at(0)) {
790 case JVM_SIGNATURE_CLASS :
791 case JVM_SIGNATURE_ARRAY : size += oopSize; break;
792
793 case JVM_SIGNATURE_BYTE :
794 case JVM_SIGNATURE_BOOLEAN : size += 1; break;
795
796 case JVM_SIGNATURE_CHAR :
797 case JVM_SIGNATURE_SHORT : size += 2; break;
798
799 case JVM_SIGNATURE_INT :
800 case JVM_SIGNATURE_FLOAT : size += 4; break;
801
802 case JVM_SIGNATURE_LONG :
803 case JVM_SIGNATURE_DOUBLE : size += 8; break;
804
805 default : ShouldNotReachHere();
806 }
807 }
808 }
809 return (u4)size;
810 }
811
812 // dumps static fields of the given class
813 void DumperSupport::dump_static_fields(DumpWriter* writer, klassOop k) {
814 HandleMark hm;
815 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
816
817 // pass 1 - count the static fields
818 u2 field_count = 0;
819 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
820 if (fldc.access_flags().is_static()) field_count++;
821 }
822
823 writer->write_u2(field_count);
824
825 // pass 2 - dump the field descriptors and raw values
826 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
827 if (fld.access_flags().is_static()) {
828 Symbol* sig = fld.signature();
829
830 writer->write_symbolID(fld.name()); // name
831 writer->write_u1(sig2tag(sig)); // type
832
833 // value
834 int offset = fld.offset();
835 address addr = (address)k + offset;
836
837 dump_field_value(writer, sig->byte_at(0), addr);
838 }
839 }
840 }
841
842 // dump the raw values of the instance fields of the given object
843 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) {
844 HandleMark hm;
845 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass());
846
847 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
848 if (!fld.access_flags().is_static()) {
849 Symbol* sig = fld.signature();
850 address addr = (address)o + fld.offset();
851
852 dump_field_value(writer, sig->byte_at(0), addr);
853 }
854 }
855 }
856
857 // dumps the definition of the instance fields for a given class
858 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, klassOop k) {
859 HandleMark hm;
860 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
861
862 // pass 1 - count the instance fields
863 u2 field_count = 0;
864 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
865 if (!fldc.access_flags().is_static()) field_count++;
866 }
867
868 writer->write_u2(field_count);
869
870 // pass 2 - dump the field descriptors
871 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
872 if (!fld.access_flags().is_static()) {
873 Symbol* sig = fld.signature();
874
875 writer->write_symbolID(fld.name()); // name
876 writer->write_u1(sig2tag(sig)); // type
877 }
878 }
879 }
880
881 // creates HPROF_GC_INSTANCE_DUMP record for the given object
882 void DumperSupport::dump_instance(DumpWriter* writer, oop o) {
883 klassOop k = o->klass();
884
885 writer->write_u1(HPROF_GC_INSTANCE_DUMP);
886 writer->write_objectID(o);
887 writer->write_u4(STACK_TRACE_ID);
888
889 // class ID
890 writer->write_classID(Klass::cast(k));
891
892 // number of bytes that follow
893 writer->write_u4(instance_size(k) );
894
895 // field values
896 dump_instance_fields(writer, o);
897 }
898
899 // creates HPROF_GC_CLASS_DUMP record for the given class and each of
900 // its array classes
901 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, klassOop k) {
902 Klass* klass = Klass::cast(k);
903 assert(klass->oop_is_instance(), "not an instanceKlass");
904 instanceKlass* ik = (instanceKlass*)klass;
905
906 writer->write_u1(HPROF_GC_CLASS_DUMP);
907
908 // class ID
909 writer->write_classID(ik);
910 writer->write_u4(STACK_TRACE_ID);
911
912 // super class ID
913 klassOop java_super = ik->java_super();
914 if (java_super == NULL) {
915 writer->write_objectID(NULL);
916 } else {
917 writer->write_classID(Klass::cast(java_super));
918 }
919
920 writer->write_objectID(ik->class_loader());
921 writer->write_objectID(ik->signers());
922 writer->write_objectID(ik->protection_domain());
923
924 // reserved
925 writer->write_objectID(NULL);
926 writer->write_objectID(NULL);
927
928 // instance size
929 writer->write_u4(DumperSupport::instance_size(k));
930
931 // size of constant pool - ignored by HAT 1.1
932 writer->write_u2(0);
933
934 // number of static fields
935 dump_static_fields(writer, k);
936
937 // description of instance fields
938 dump_instance_field_descriptors(writer, k);
939
940 // array classes
941 k = klass->array_klass_or_null();
942 while (k != NULL) {
943 Klass* klass = Klass::cast(k);
944 assert(klass->oop_is_objArray(), "not an objArrayKlass");
945
946 writer->write_u1(HPROF_GC_CLASS_DUMP);
947 writer->write_classID(klass);
948 writer->write_u4(STACK_TRACE_ID);
949
950 // super class of array classes is java.lang.Object
951 java_super = klass->java_super();
952 assert(java_super != NULL, "checking");
953 writer->write_classID(Klass::cast(java_super));
954
955 writer->write_objectID(ik->class_loader());
956 writer->write_objectID(ik->signers());
957 writer->write_objectID(ik->protection_domain());
958
959 writer->write_objectID(NULL); // reserved
960 writer->write_objectID(NULL);
961 writer->write_u4(0); // instance size
962 writer->write_u2(0); // constant pool
963 writer->write_u2(0); // static fields
964 writer->write_u2(0); // instance fields
965
966 // get the array class for the next rank
967 k = klass->array_klass_or_null();
968 }
969 }
970
971 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
972 // class (and each multi-dimensional array class too)
973 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, klassOop k) {
974 // array classes
975 while (k != NULL) {
976 Klass* klass = Klass::cast(k);
977
978 writer->write_u1(HPROF_GC_CLASS_DUMP);
979 writer->write_classID(klass);
980 writer->write_u4(STACK_TRACE_ID);
981
982 // super class of array classes is java.lang.Object
983 klassOop java_super = klass->java_super();
984 assert(java_super != NULL, "checking");
985 writer->write_classID(Klass::cast(java_super));
986
987 writer->write_objectID(NULL); // loader
988 writer->write_objectID(NULL); // signers
989 writer->write_objectID(NULL); // protection domain
990
991 writer->write_objectID(NULL); // reserved
992 writer->write_objectID(NULL);
993 writer->write_u4(0); // instance size
994 writer->write_u2(0); // constant pool
995 writer->write_u2(0); // static fields
996 writer->write_u2(0); // instance fields
997
998 // get the array class for the next rank
999 k = klass->array_klass_or_null();
1000 }
1001 }
1002
1003 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1004 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) {
1005
1006 // filter this
1007 if (array->klass() == Universe::systemObjArrayKlassObj()) return;
1008
1009 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP);
1010 writer->write_objectID(array);
1011 writer->write_u4(STACK_TRACE_ID);
1012 writer->write_u4((u4)array->length());
1013
1014 // array class ID
1015 writer->write_classID(Klass::cast(array->klass()));
1016
1017 // [id]* elements
1018 for (int index=0; index<array->length(); index++) {
1019 oop o = array->obj_at(index);
1020 writer->write_objectID(o);
1021 }
1022 }
1023
1024 #define WRITE_ARRAY(Array, Type, Size) \
1025 for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); }
1026
1027
1028 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1029 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) {
1030 BasicType type = typeArrayKlass::cast(array->klass())->element_type();
1031
1032 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP);
1033 writer->write_objectID(array);
1034 writer->write_u4(STACK_TRACE_ID);
1035 writer->write_u4((u4)array->length());
1036 writer->write_u1(type2tag(type));
1037
1038 // nothing to copy
1039 if (array->length() == 0) {
1040 return;
1041 }
1042
1043 // If the byte ordering is big endian then we can copy most types directly
1044 int length_in_bytes = array->length() * type2aelembytes(type);
1045 assert(length_in_bytes > 0, "nothing to copy");
1046
1047 switch (type) {
1048 case T_INT : {
1049 if (Bytes::is_Java_byte_ordering_different()) {
1050 WRITE_ARRAY(array, int, u4);
1051 } else {
1052 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes);
1053 }
1054 break;
1055 }
1056 case T_BYTE : {
1057 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes);
1058 break;
1059 }
1060 case T_CHAR : {
1061 if (Bytes::is_Java_byte_ordering_different()) {
1062 WRITE_ARRAY(array, char, u2);
1063 } else {
1064 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes);
1065 }
1066 break;
1067 }
1068 case T_SHORT : {
1069 if (Bytes::is_Java_byte_ordering_different()) {
1070 WRITE_ARRAY(array, short, u2);
1071 } else {
1072 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes);
1073 }
1074 break;
1075 }
1076 case T_BOOLEAN : {
1077 if (Bytes::is_Java_byte_ordering_different()) {
1078 WRITE_ARRAY(array, bool, u1);
1079 } else {
1080 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes);
1081 }
1082 break;
1083 }
1084 case T_LONG : {
1085 if (Bytes::is_Java_byte_ordering_different()) {
1086 WRITE_ARRAY(array, long, u8);
1087 } else {
1088 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes);
1089 }
1090 break;
1091 }
1092
1093 // handle float/doubles in a special value to ensure than NaNs are
1094 // written correctly. TO DO: Check if we can avoid this on processors that
1095 // use IEEE 754.
1096
1097 case T_FLOAT : {
1098 for (int i=0; i<array->length(); i++) {
1099 dump_float( writer, array->float_at(i) );
1100 }
1101 break;
1102 }
1103 case T_DOUBLE : {
1104 for (int i=0; i<array->length(); i++) {
1105 dump_double( writer, array->double_at(i) );
1106 }
1107 break;
1108 }
1109 default : ShouldNotReachHere();
1110 }
1111 }
1112
1113 // create a HPROF_FRAME record of the given methodOop and bci
1114 void DumperSupport::dump_stack_frame(DumpWriter* writer,
1115 int frame_serial_num,
1116 int class_serial_num,
1117 methodOop m,
1118 int bci) {
1119 int line_number;
1120 if (m->is_native()) {
1121 line_number = -3; // native frame
1122 } else {
1123 line_number = m->line_number_from_bci(bci);
1124 }
1125
1126 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1127 writer->write_id(frame_serial_num); // frame serial number
1128 writer->write_symbolID(m->name()); // method's name
1129 writer->write_symbolID(m->signature()); // method's signature
1130
1131 assert(Klass::cast(m->method_holder())->oop_is_instance(), "not instanceKlass");
1132 writer->write_symbolID(instanceKlass::cast(m->method_holder())->source_file_name()); // source file name
1133 writer->write_u4(class_serial_num); // class serial number
1134 writer->write_u4((u4) line_number); // line number
1135 }
1136
1137
1138 // Support class used to generate HPROF_UTF8 records from the entries in the
1139 // SymbolTable.
1140
1141 class SymbolTableDumper : public SymbolClosure {
1142 private:
1143 DumpWriter* _writer;
1144 DumpWriter* writer() const { return _writer; }
1145 public:
1146 SymbolTableDumper(DumpWriter* writer) { _writer = writer; }
1147 void do_symbol(Symbol** p);
1148 };
1149
1150 void SymbolTableDumper::do_symbol(Symbol** p) {
1151 ResourceMark rm;
1152 Symbol* sym = load_symbol(p);
1153 int len = sym->utf8_length();
1154 if (len > 0) {
1155 char* s = sym->as_utf8();
1156 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1157 writer()->write_symbolID(sym);
1158 writer()->write_raw(s, len);
1159 }
1160 }
1161
1162 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
1163
1164 class JNILocalsDumper : public OopClosure {
1165 private:
1166 DumpWriter* _writer;
1167 u4 _thread_serial_num;
1168 int _frame_num;
1169 DumpWriter* writer() const { return _writer; }
1170 public:
1171 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) {
1172 _writer = writer;
1173 _thread_serial_num = thread_serial_num;
1174 _frame_num = -1; // default - empty stack
1175 }
1176 void set_frame_number(int n) { _frame_num = n; }
1177 void do_oop(oop* obj_p);
1178 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1179 };
1180
1181
1182 void JNILocalsDumper::do_oop(oop* obj_p) {
1183 // ignore null or deleted handles
1184 oop o = *obj_p;
1185 if (o != NULL && o != JNIHandles::deleted_handle()) {
1186 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL);
1187 writer()->write_objectID(o);
1188 writer()->write_u4(_thread_serial_num);
1189 writer()->write_u4((u4)_frame_num);
1190 }
1191 }
1192
1193
1194 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
1195
1196 class JNIGlobalsDumper : public OopClosure {
1197 private:
1198 DumpWriter* _writer;
1199 DumpWriter* writer() const { return _writer; }
1200
1201 public:
1202 JNIGlobalsDumper(DumpWriter* writer) {
1203 _writer = writer;
1204 }
1205 void do_oop(oop* obj_p);
1206 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1207 };
1208
1209 void JNIGlobalsDumper::do_oop(oop* obj_p) {
1210 oop o = *obj_p;
1211
1212 // ignore these
1213 if (o == NULL || o == JNIHandles::deleted_handle()) return;
1214
1215 // we ignore global ref to symbols and other internal objects
1216 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) {
1217 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL);
1218 writer()->write_objectID(o);
1219 writer()->write_objectID((oopDesc*)obj_p); // global ref ID
1220 }
1221 };
1222
1223
1224 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records
1225
1226 class MonitorUsedDumper : public OopClosure {
1227 private:
1228 DumpWriter* _writer;
1229 DumpWriter* writer() const { return _writer; }
1230 public:
1231 MonitorUsedDumper(DumpWriter* writer) {
1232 _writer = writer;
1233 }
1234 void do_oop(oop* obj_p) {
1235 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED);
1236 writer()->write_objectID(*obj_p);
1237 }
1238 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1239 };
1240
1241
1242 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
1243
1244 class StickyClassDumper : public OopClosure {
1245 private:
1246 DumpWriter* _writer;
1247 DumpWriter* writer() const { return _writer; }
1248 public:
1249 StickyClassDumper(DumpWriter* writer) {
1250 _writer = writer;
1251 }
1252 void do_oop(oop* obj_p);
1253 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1254 };
1255
1256 void StickyClassDumper::do_oop(oop* obj_p) {
1257 if (*obj_p != NULL) {
1258 oop o = *obj_p;
1259 if (o->is_klass()) {
1260 klassOop k = klassOop(o);
1261 if (Klass::cast(k)->oop_is_instance()) {
1262 instanceKlass* ik = instanceKlass::cast(k);
1263 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS);
1264 writer()->write_classID(ik);
1265 }
1266 }
1267 }
1268 }
1269
1270
1271 class VM_HeapDumper;
1272
1273 // Support class using when iterating over the heap.
1274
1275 class HeapObjectDumper : public ObjectClosure {
1276 private:
1277 VM_HeapDumper* _dumper;
1278 DumpWriter* _writer;
1279
1280 VM_HeapDumper* dumper() { return _dumper; }
1281 DumpWriter* writer() { return _writer; }
1282
1283 // used to indicate that a record has been writen
1284 void mark_end_of_record();
1285
1286 public:
1287 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) {
1288 _dumper = dumper;
1289 _writer = writer;
1290 }
1291
1292 // called for each object in the heap
1293 void do_object(oop o);
1294 };
1295
1296 void HeapObjectDumper::do_object(oop o) {
1297 // hide the sentinel for deleted handles
1298 if (o == JNIHandles::deleted_handle()) return;
1299
1300 // ignore KlassKlass objects
1301 if (o->is_klass()) return;
1302
1303 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records
1304 if (o->klass() == SystemDictionary::Class_klass()) {
1305 if (!java_lang_Class::is_primitive(o)) {
1306 return;
1307 }
1308 }
1309
1310 // create a HPROF_GC_INSTANCE record for each object
1311 if (o->is_instance()) {
1312 DumperSupport::dump_instance(writer(), o);
1313 mark_end_of_record();
1314 } else {
1315 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
1316 if (o->is_objArray()) {
1317 DumperSupport::dump_object_array(writer(), objArrayOop(o));
1318 mark_end_of_record();
1319 } else {
1320 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
1321 if (o->is_typeArray()) {
1322 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
1323 mark_end_of_record();
1324 }
1325 }
1326 }
1327 }
1328
1329 // The VM operation that performs the heap dump
1330 class VM_HeapDumper : public VM_GC_Operation {
1331 private:
1332 static VM_HeapDumper* _global_dumper;
1333 static DumpWriter* _global_writer;
1334 DumpWriter* _local_writer;
1335 JavaThread* _oome_thread;
1336 methodOop _oome_constructor;
1337 bool _gc_before_heap_dump;
1338 bool _is_segmented_dump;
1339 jlong _dump_start;
1340 GrowableArray<Klass*>* _klass_map;
1341 ThreadStackTrace** _stack_traces;
1342 int _num_threads;
1343
1344 // accessors and setters
1345 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; }
1346 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; }
1347 void set_global_dumper() {
1348 assert(_global_dumper == NULL, "Error");
1349 _global_dumper = this;
1350 }
1351 void set_global_writer() {
1352 assert(_global_writer == NULL, "Error");
1353 _global_writer = _local_writer;
1354 }
1355 void clear_global_dumper() { _global_dumper = NULL; }
1356 void clear_global_writer() { _global_writer = NULL; }
1357
1358 bool is_segmented_dump() const { return _is_segmented_dump; }
1359 void set_segmented_dump() { _is_segmented_dump = true; }
1360 jlong dump_start() const { return _dump_start; }
1361 void set_dump_start(jlong pos);
1362
1363 bool skip_operation() const;
1364
1365 // writes a HPROF_LOAD_CLASS record
1366 static void do_load_class(klassOop k);
1367
1368 // writes a HPROF_GC_CLASS_DUMP record for the given class
1369 // (and each array class too)
1370 static void do_class_dump(klassOop k);
1371
1372 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1373 // array (and each multi-dimensional array too)
1374 static void do_basic_type_array_class_dump(klassOop k);
1375
1376 // HPROF_GC_ROOT_THREAD_OBJ records
1377 int do_thread(JavaThread* thread, u4 thread_serial_num);
1378 void do_threads();
1379
1380 void add_class_serial_number(Klass* k, int serial_num) {
1381 _klass_map->at_put_grow(serial_num, k);
1382 }
1383
1384 // HPROF_TRACE and HPROF_FRAME records
1385 void dump_stack_traces();
1386
1387 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record
1388 void write_dump_header();
1389
1390 // fixes up the length of the current dump record
1391 void write_current_dump_record_length();
1392
1393 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END
1394 // record in the case of a segmented heap dump)
1395 void end_of_dump();
1396
1397 public:
1398 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) :
1399 VM_GC_Operation(0 /* total collections, dummy, ignored */,
1400 GCCause::_heap_dump /* GC Cause */,
1401 0 /* total full collections, dummy, ignored */,
1402 gc_before_heap_dump) {
1403 _local_writer = writer;
1404 _gc_before_heap_dump = gc_before_heap_dump;
1405 _is_segmented_dump = false;
1406 _dump_start = (jlong)-1;
1407 _klass_map = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true);
1408 _stack_traces = NULL;
1409 _num_threads = 0;
1410 if (oome) {
1411 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread");
1412 // get OutOfMemoryError zero-parameter constructor
1413 instanceKlass* oome_ik = instanceKlass::cast(SystemDictionary::OutOfMemoryError_klass());
1414 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(),
1415 vmSymbols::void_method_signature());
1416 // get thread throwing OOME when generating the heap dump at OOME
1417 _oome_thread = JavaThread::current();
1418 } else {
1419 _oome_thread = NULL;
1420 _oome_constructor = NULL;
1421 }
1422 }
1423 ~VM_HeapDumper() {
1424 if (_stack_traces != NULL) {
1425 for (int i=0; i < _num_threads; i++) {
1426 delete _stack_traces[i];
1427 }
1428 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces);
1429 }
1430 delete _klass_map;
1431 }
1432
1433 VMOp_Type type() const { return VMOp_HeapDumper; }
1434 // used to mark sub-record boundary
1435 void check_segment_length();
1436 void doit();
1437 };
1438
1439 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL;
1440 DumpWriter* VM_HeapDumper::_global_writer = NULL;
1441
1442 bool VM_HeapDumper::skip_operation() const {
1443 return false;
1444 }
1445
1446 // sets the dump starting position
1447 void VM_HeapDumper::set_dump_start(jlong pos) {
1448 _dump_start = pos;
1449 }
1450
1451 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record
1452 void VM_HeapDumper::write_dump_header() {
1453 if (writer()->is_open()) {
1454 if (is_segmented_dump()) {
1455 writer()->write_u1(HPROF_HEAP_DUMP_SEGMENT);
1456 } else {
1457 writer()->write_u1(HPROF_HEAP_DUMP);
1458 }
1459 writer()->write_u4(0); // current ticks
1460
1461 // record the starting position for the dump (its length will be fixed up later)
1462 set_dump_start(writer()->current_offset());
1463 writer()->write_u4(0);
1464 }
1465 }
1466
1467 // fixes up the length of the current dump record
1468 void VM_HeapDumper::write_current_dump_record_length() {
1469 if (writer()->is_open()) {
1470 assert(dump_start() >= 0, "no dump start recorded");
1471
1472 // calculate the size of the dump record
1473 jlong dump_end = writer()->current_offset();
1474 jlong dump_len = (dump_end - dump_start() - 4);
1475
1476 // record length must fit in a u4
1477 if (dump_len > (jlong)(4L*(jlong)G)) {
1478 warning("record is too large");
1479 }
1480
1481 // seek to the dump start and fix-up the length
1482 writer()->seek_to_offset(dump_start());
1483 writer()->write_u4((u4)dump_len);
1484
1485 // adjust the total size written to keep the bytes written correct.
1486 writer()->adjust_bytes_written(-((long) sizeof(u4)));
1487
1488 // seek to dump end so we can continue
1489 writer()->seek_to_offset(dump_end);
1490
1491 // no current dump record
1492 set_dump_start((jlong)-1);
1493 }
1494 }
1495
1496 // used on a sub-record boundary to check if we need to start a
1497 // new segment.
1498 void VM_HeapDumper::check_segment_length() {
1499 if (writer()->is_open()) {
1500 if (is_segmented_dump()) {
1501 // don't use current_offset that would be too expensive on a per record basis
1502 jlong dump_end = writer()->bytes_written() + writer()->bytes_unwritten();
1503 assert(dump_end == writer()->current_offset(), "checking");
1504 jlong dump_len = (dump_end - dump_start() - 4);
1505 assert(dump_len >= 0 && dump_len <= max_juint, "bad dump length");
1506
1507 if (dump_len > (jlong)HeapDumpSegmentSize) {
1508 write_current_dump_record_length();
1509 write_dump_header();
1510 }
1511 }
1512 }
1513 }
1514
1515 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END
1516 // record in the case of a segmented heap dump)
1517 void VM_HeapDumper::end_of_dump() {
1518 if (writer()->is_open()) {
1519 write_current_dump_record_length();
1520
1521 // for segmented dump we write the end record
1522 if (is_segmented_dump()) {
1523 writer()->write_u1(HPROF_HEAP_DUMP_END);
1524 writer()->write_u4(0);
1525 writer()->write_u4(0);
1526 }
1527 }
1528 }
1529
1530 // marks sub-record boundary
1531 void HeapObjectDumper::mark_end_of_record() {
1532 dumper()->check_segment_length();
1533 }
1534
1535 // writes a HPROF_LOAD_CLASS record for the class (and each of its
1536 // array classes)
1537 void VM_HeapDumper::do_load_class(klassOop k) {
1538 static u4 class_serial_num = 0;
1539
1540 // len of HPROF_LOAD_CLASS record
1541 u4 remaining = 2*oopSize + 2*sizeof(u4);
1542
1543 // write a HPROF_LOAD_CLASS for the class and each array class
1544 do {
1545 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
1546
1547 // class serial number is just a number
1548 writer()->write_u4(++class_serial_num);
1549
1550 // class ID
1551 Klass* klass = Klass::cast(k);
1552 writer()->write_classID(klass);
1553
1554 // add the klassOop and class serial number pair
1555 dumper()->add_class_serial_number(klass, class_serial_num);
1556
1557 writer()->write_u4(STACK_TRACE_ID);
1558
1559 // class name ID
1560 Symbol* name = klass->name();
1561 writer()->write_symbolID(name);
1562
1563 // write a LOAD_CLASS record for the array type (if it exists)
1564 k = klass->array_klass_or_null();
1565 } while (k != NULL);
1566 }
1567
1568 // writes a HPROF_GC_CLASS_DUMP record for the given class
1569 void VM_HeapDumper::do_class_dump(klassOop k) {
1570 DumperSupport::dump_class_and_array_classes(writer(), k);
1571 }
1572
1573 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1574 // array (and each multi-dimensional array too)
1575 void VM_HeapDumper::do_basic_type_array_class_dump(klassOop k) {
1576 DumperSupport::dump_basic_type_array_class(writer(), k);
1577 }
1578
1579 // Walk the stack of the given thread.
1580 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local
1581 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local
1582 //
1583 // It returns the number of Java frames in this thread stack
1584 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) {
1585 JNILocalsDumper blk(writer(), thread_serial_num);
1586
1587 oop threadObj = java_thread->threadObj();
1588 assert(threadObj != NULL, "sanity check");
1589
1590 int stack_depth = 0;
1591 if (java_thread->has_last_Java_frame()) {
1592
1593 // vframes are resource allocated
1594 Thread* current_thread = Thread::current();
1595 ResourceMark rm(current_thread);
1596 HandleMark hm(current_thread);
1597
1598 RegisterMap reg_map(java_thread);
1599 frame f = java_thread->last_frame();
1600 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread);
1601 frame* last_entry_frame = NULL;
1602 int extra_frames = 0;
1603
1604 if (java_thread == _oome_thread && _oome_constructor != NULL) {
1605 extra_frames++;
1606 }
1607 while (vf != NULL) {
1608 blk.set_frame_number(stack_depth);
1609 if (vf->is_java_frame()) {
1610
1611 // java frame (interpreted, compiled, ...)
1612 javaVFrame *jvf = javaVFrame::cast(vf);
1613 if (!(jvf->method()->is_native())) {
1614 StackValueCollection* locals = jvf->locals();
1615 for (int slot=0; slot<locals->size(); slot++) {
1616 if (locals->at(slot)->type() == T_OBJECT) {
1617 oop o = locals->obj_at(slot)();
1618
1619 if (o != NULL) {
1620 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1621 writer()->write_objectID(o);
1622 writer()->write_u4(thread_serial_num);
1623 writer()->write_u4((u4) (stack_depth + extra_frames));
1624 }
1625 }
1626 }
1627 } else {
1628 // native frame
1629 if (stack_depth == 0) {
1630 // JNI locals for the top frame.
1631 java_thread->active_handles()->oops_do(&blk);
1632 } else {
1633 if (last_entry_frame != NULL) {
1634 // JNI locals for the entry frame
1635 assert(last_entry_frame->is_entry_frame(), "checking");
1636 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk);
1637 }
1638 }
1639 }
1640 // increment only for Java frames
1641 stack_depth++;
1642 last_entry_frame = NULL;
1643
1644 } else {
1645 // externalVFrame - if it's an entry frame then report any JNI locals
1646 // as roots when we find the corresponding native javaVFrame
1647 frame* fr = vf->frame_pointer();
1648 assert(fr != NULL, "sanity check");
1649 if (fr->is_entry_frame()) {
1650 last_entry_frame = fr;
1651 }
1652 }
1653 vf = vf->sender();
1654 }
1655 } else {
1656 // no last java frame but there may be JNI locals
1657 java_thread->active_handles()->oops_do(&blk);
1658 }
1659 return stack_depth;
1660 }
1661
1662
1663 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk
1664 // the stack so that locals and JNI locals are dumped.
1665 void VM_HeapDumper::do_threads() {
1666 for (int i=0; i < _num_threads; i++) {
1667 JavaThread* thread = _stack_traces[i]->thread();
1668 oop threadObj = thread->threadObj();
1669 u4 thread_serial_num = i+1;
1670 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID;
1671 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ);
1672 writer()->write_objectID(threadObj);
1673 writer()->write_u4(thread_serial_num); // thread number
1674 writer()->write_u4(stack_serial_num); // stack trace serial number
1675 int num_frames = do_thread(thread, thread_serial_num);
1676 assert(num_frames == _stack_traces[i]->get_stack_depth(),
1677 "total number of Java frames not matched");
1678 }
1679 }
1680
1681
1682 // The VM operation that dumps the heap. The dump consists of the following
1683 // records:
1684 //
1685 // HPROF_HEADER
1686 // [HPROF_UTF8]*
1687 // [HPROF_LOAD_CLASS]*
1688 // [[HPROF_FRAME]*|HPROF_TRACE]*
1689 // [HPROF_GC_CLASS_DUMP]*
1690 // HPROF_HEAP_DUMP
1691 //
1692 // The HPROF_TRACE records represent the stack traces where the heap dump
1693 // is generated and a "dummy trace" record which does not include
1694 // any frames. The dummy trace record is used to be referenced as the
1695 // unknown object alloc site.
1696 //
1697 // The HPROF_HEAP_DUMP record has a length following by sub-records. To allow
1698 // the heap dump be generated in a single pass we remember the position of
1699 // the dump length and fix it up after all sub-records have been written.
1700 // To generate the sub-records we iterate over the heap, writing
1701 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP
1702 // records as we go. Once that is done we write records for some of the GC
1703 // roots.
1704
1705 void VM_HeapDumper::doit() {
1706
1707 HandleMark hm;
1708 CollectedHeap* ch = Universe::heap();
1709 if (_gc_before_heap_dump) {
1710 ch->collect_as_vm_thread(GCCause::_heap_dump);
1711 } else {
1712 // make the heap parsable (no need to retire TLABs)
1713 ch->ensure_parsability(false);
1714 }
1715
1716 // At this point we should be the only dumper active, so
1717 // the following should be safe.
1718 set_global_dumper();
1719 set_global_writer();
1720
1721 // Write the file header - use 1.0.2 for large heaps, otherwise 1.0.1
1722 size_t used = ch->used();
1723 const char* header;
1724 if (used > (size_t)SegmentedHeapDumpThreshold) {
1725 set_segmented_dump();
1726 header = "JAVA PROFILE 1.0.2";
1727 } else {
1728 header = "JAVA PROFILE 1.0.1";
1729 }
1730
1731 // header is few bytes long - no chance to overflow int
1732 writer()->write_raw((void*)header, (int)strlen(header));
1733 writer()->write_u1(0); // terminator
1734 writer()->write_u4(oopSize);
1735 writer()->write_u8(os::javaTimeMillis());
1736
1737 // HPROF_UTF8 records
1738 SymbolTableDumper sym_dumper(writer());
1739 SymbolTable::symbols_do(&sym_dumper);
1740
1741 // write HPROF_LOAD_CLASS records
1742 SystemDictionary::classes_do(&do_load_class);
1743 Universe::basic_type_classes_do(&do_load_class);
1744
1745 // write HPROF_FRAME and HPROF_TRACE records
1746 // this must be called after _klass_map is built when iterating the classes above.
1747 dump_stack_traces();
1748
1749 // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT
1750 write_dump_header();
1751
1752 // Writes HPROF_GC_CLASS_DUMP records
1753 SystemDictionary::classes_do(&do_class_dump);
1754 Universe::basic_type_classes_do(&do_basic_type_array_class_dump);
1755 check_segment_length();
1756
1757 // writes HPROF_GC_INSTANCE_DUMP records.
1758 // After each sub-record is written check_segment_length will be invoked. When
1759 // generated a segmented heap dump this allows us to check if the current
1760 // segment exceeds a threshold and if so, then a new segment is started.
1761 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk
1762 // of the heap dump.
1763 HeapObjectDumper obj_dumper(this, writer());
1764 Universe::heap()->safe_object_iterate(&obj_dumper);
1765
1766 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
1767 do_threads();
1768 check_segment_length();
1769
1770 // HPROF_GC_ROOT_MONITOR_USED
1771 MonitorUsedDumper mon_dumper(writer());
1772 ObjectSynchronizer::oops_do(&mon_dumper);
1773 check_segment_length();
1774
1775 // HPROF_GC_ROOT_JNI_GLOBAL
1776 JNIGlobalsDumper jni_dumper(writer());
1777 JNIHandles::oops_do(&jni_dumper);
1778 check_segment_length();
1779
1780 // HPROF_GC_ROOT_STICKY_CLASS
1781 StickyClassDumper class_dumper(writer());
1782 SystemDictionary::always_strong_oops_do(&class_dumper);
1783
1784 // fixes up the length of the dump record. In the case of a segmented
1785 // heap then the HPROF_HEAP_DUMP_END record is also written.
1786 end_of_dump();
1787
1788 // Now we clear the global variables, so that a future dumper might run.
1789 clear_global_dumper();
1790 clear_global_writer();
1791 }
1792
1793 void VM_HeapDumper::dump_stack_traces() {
1794 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites
1795 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4));
1796 writer()->write_u4((u4) STACK_TRACE_ID);
1797 writer()->write_u4(0); // thread number
1798 writer()->write_u4(0); // frame count
1799
1800 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads());
1801 int frame_serial_num = 0;
1802 for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) {
1803 oop threadObj = thread->threadObj();
1804 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) {
1805 // dump thread stack trace
1806 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false);
1807 stack_trace->dump_stack_at_safepoint(-1);
1808 _stack_traces[_num_threads++] = stack_trace;
1809
1810 // write HPROF_FRAME records for this thread's stack trace
1811 int depth = stack_trace->get_stack_depth();
1812 int thread_frame_start = frame_serial_num;
1813 int extra_frames = 0;
1814 // write fake frame that makes it look like the thread, which caused OOME,
1815 // is in the OutOfMemoryError zero-parameter constructor
1816 if (thread == _oome_thread && _oome_constructor != NULL) {
1817 int oome_serial_num = _klass_map->find(Klass::cast(_oome_constructor->method_holder()));
1818 // the class serial number starts from 1
1819 assert(oome_serial_num > 0, "OutOfMemoryError class not found");
1820 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num,
1821 _oome_constructor, 0);
1822 extra_frames++;
1823 }
1824 for (int j=0; j < depth; j++) {
1825 StackFrameInfo* frame = stack_trace->stack_frame_at(j);
1826 methodOop m = frame->method();
1827 int class_serial_num = _klass_map->find(Klass::cast(m->method_holder()));
1828 // the class serial number starts from 1
1829 assert(class_serial_num > 0, "class not found");
1830 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci());
1831 }
1832 depth += extra_frames;
1833
1834 // write HPROF_TRACE record for one thread
1835 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize);
1836 int stack_serial_num = _num_threads + STACK_TRACE_ID;
1837 writer()->write_u4(stack_serial_num); // stack trace serial number
1838 writer()->write_u4((u4) _num_threads); // thread serial number
1839 writer()->write_u4(depth); // frame count
1840 for (int j=1; j <= depth; j++) {
1841 writer()->write_id(thread_frame_start + j);
1842 }
1843 }
1844 }
1845 }
1846
1847 // dump the heap to given path.
1848 int HeapDumper::dump(const char* path) {
1849 assert(path != NULL && strlen(path) > 0, "path missing");
1850
1851 // print message in interactive case
1852 if (print_to_tty()) {
1853 tty->print_cr("Dumping heap to %s ...", path);
1854 timer()->start();
1855 }
1856
1857 // create the dump writer. If the file can be opened then bail
1858 DumpWriter writer(path);
1859 if (!writer.is_open()) {
1860 set_error(writer.error());
1861 if (print_to_tty()) {
1862 tty->print_cr("Unable to create %s: %s", path,
1863 (error() != NULL) ? error() : "reason unknown");
1864 }
1865 return -1;
1866 }
1867
1868 // generate the dump
1869 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome);
1870 if (Thread::current()->is_VM_thread()) {
1871 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint");
1872 dumper.doit();
1873 } else {
1874 VMThread::execute(&dumper);
1875 }
1876
1877 // close dump file and record any error that the writer may have encountered
1878 writer.close();
1879 set_error(writer.error());
1880
1881 // print message in interactive case
1882 if (print_to_tty()) {
1883 timer()->stop();
1884 if (error() == NULL) {
1885 char msg[256];
1886 sprintf(msg, "Heap dump file created [%s bytes in %3.3f secs]",
1887 os::jlong_format_specifier(), timer()->seconds());
1888 tty->print_cr(msg, writer.bytes_written());
1889 } else {
1890 tty->print_cr("Dump file is incomplete: %s", writer.error());
1891 }
1892 }
1893
1894 return (writer.error() == NULL) ? 0 : -1;
1895 }
1896
1897 // stop timer (if still active), and free any error string we might be holding
1898 HeapDumper::~HeapDumper() {
1899 if (timer()->is_active()) {
1900 timer()->stop();
1901 }
1902 set_error(NULL);
1903 }
1904
1905
1906 // returns the error string (resource allocated), or NULL
1907 char* HeapDumper::error_as_C_string() const {
1908 if (error() != NULL) {
1909 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1);
1910 strcpy(str, error());
1911 return str;
1912 } else {
1913 return NULL;
1914 }
1915 }
1916
1917 // set the error string
1918 void HeapDumper::set_error(char* error) {
1919 if (_error != NULL) {
1920 os::free(_error);
1921 }
1922 if (error == NULL) {
1923 _error = NULL;
1924 } else {
1925 _error = os::strdup(error);
1926 assert(_error != NULL, "allocation failure");
1927 }
1928 }
1929
1930 // Called by out-of-memory error reporting by a single Java thread
1931 // outside of a JVM safepoint
1932 void HeapDumper::dump_heap_from_oome() {
1933 HeapDumper::dump_heap(true);
1934 }
1935
1936 // Called by error reporting by a single Java thread outside of a JVM safepoint,
1937 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various
1938 // callers are strictly serialized and guaranteed not to interfere below. For more
1939 // general use, however, this method will need modification to prevent
1940 // inteference when updating the static variables base_path and dump_file_seq below.
1941 void HeapDumper::dump_heap() {
1942 HeapDumper::dump_heap(false);
1943 }
1944
1945 void HeapDumper::dump_heap(bool oome) {
1946 static char base_path[JVM_MAXPATHLEN] = {'\0'};
1947 static uint dump_file_seq = 0;
1948 char* my_path;
1949 const int max_digit_chars = 20;
1950
1951 const char* dump_file_name = "java_pid";
1952 const char* dump_file_ext = ".hprof";
1953
1954 // The dump file defaults to java_pid<pid>.hprof in the current working
1955 // directory. HeapDumpPath=<file> can be used to specify an alternative
1956 // dump file name or a directory where dump file is created.
1957 if (dump_file_seq == 0) { // first time in, we initialize base_path
1958 // Calculate potentially longest base path and check if we have enough
1959 // allocated statically.
1960 const size_t total_length =
1961 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) +
1962 strlen(os::file_separator()) + max_digit_chars +
1963 strlen(dump_file_name) + strlen(dump_file_ext) + 1;
1964 if (total_length > sizeof(base_path)) {
1965 warning("Cannot create heap dump file. HeapDumpPath is too long.");
1966 return;
1967 }
1968
1969 bool use_default_filename = true;
1970 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') {
1971 // HeapDumpPath=<file> not specified
1972 } else {
1973 strncpy(base_path, HeapDumpPath, sizeof(base_path));
1974 // check if the path is a directory (must exist)
1975 DIR* dir = os::opendir(base_path);
1976 if (dir == NULL) {
1977 use_default_filename = false;
1978 } else {
1979 // HeapDumpPath specified a directory. We append a file separator
1980 // (if needed).
1981 os::closedir(dir);
1982 size_t fs_len = strlen(os::file_separator());
1983 if (strlen(base_path) >= fs_len) {
1984 char* end = base_path;
1985 end += (strlen(base_path) - fs_len);
1986 if (strcmp(end, os::file_separator()) != 0) {
1987 strcat(base_path, os::file_separator());
1988 }
1989 }
1990 }
1991 }
1992 // If HeapDumpPath wasn't a file name then we append the default name
1993 if (use_default_filename) {
1994 const size_t dlen = strlen(base_path); // if heap dump dir specified
1995 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s",
1996 dump_file_name, os::current_process_id(), dump_file_ext);
1997 }
1998 const size_t len = strlen(base_path) + 1;
1999 my_path = (char*)os::malloc(len);
2000 if (my_path == NULL) {
2001 warning("Cannot create heap dump file. Out of system memory.");
2002 return;
2003 }
2004 strncpy(my_path, base_path, len);
2005 } else {
2006 // Append a sequence number id for dumps following the first
2007 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0
2008 my_path = (char*)os::malloc(len);
2009 if (my_path == NULL) {
2010 warning("Cannot create heap dump file. Out of system memory.");
2011 return;
2012 }
2013 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq);
2014 }
2015 dump_file_seq++; // increment seq number for next time we dump
2016
2017 HeapDumper dumper(false /* no GC before heap dump */,
2018 true /* send to tty */,
2019 oome /* pass along out-of-memory-error flag */);
2020 dumper.dump(my_path);
2021 os::free(my_path);
2022 }