Mercurial > jdk8-mips64-public > hotspot / file revision
src/share/vm/services/heapDumper.cpp@73d689add964
src/share/vm/services/heapDumper.cpp
Thu, 27 Dec 2018 11:43:33 +0800
- author
- aoqi
- date
- Thu, 27 Dec 2018 11:43:33 +0800
- changeset 9448
- 73d689add964
- parent 9344
- ad057f2e3211
- parent 8604
- 04d83ba48607
- child 9703
- 2fdf635bcf28
- permissions
- -rw-r--r--
Merge
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 */
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
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 */
315 // HPROF tags
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,
332 // 1.0.2 record types
333 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
334 HPROF_HEAP_DUMP_END = 0x2C,
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,
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;
364 // Default stack trace ID (used for dummy HPROF_TRACE record)
365 enum {
366 STACK_TRACE_ID = 1,
367 INITIAL_CLASS_COUNT = 200
368 };
370 // Supports I/O operations on a dump file
372 class DumpWriter : public StackObj {
373 private:
374 enum {
375 io_buffer_size = 8*M
376 };
378 int _fd; // file descriptor (-1 if dump file not open)
379 julong _bytes_written; // number of byte written to dump file
381 char* _buffer; // internal buffer
382 size_t _size;
383 size_t _pos;
385 char* _error; // error message when I/O fails
387 void set_file_descriptor(int fd) { _fd = fd; }
388 int file_descriptor() const { return _fd; }
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; }
395 void set_error(const char* error) { _error = (char*)os::strdup(error); }
397 // all I/O go through this function
398 void write_internal(void* s, size_t len);
400 public:
401 DumpWriter(const char* path);
402 ~DumpWriter();
404 void close();
405 bool is_open() const { return file_descriptor() >= 0; }
406 void flush();
408 // total number of bytes written to the disk
409 julong bytes_written() const { return _bytes_written; }
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; }
415 // number of (buffered) bytes as yet unwritten to the dump file
416 size_t bytes_unwritten() const { return position(); }
418 char* error() const { return _error; }
420 jlong current_offset();
421 void seek_to_offset(jlong pos);
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 };
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
451 // if the open failed we record the error
452 if (_fd < 0) {
453 _error = (char*)os::strdup(strerror(errno));
454 }
455 }
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 }
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 }
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);
485 if (n < 0) {
486 set_error(strerror(errno));
487 ::close(file_descriptor());
488 set_file_descriptor(-1);
489 return;
490 }
492 _bytes_written += n;
493 pos += n;
494 len -= n;
495 }
496 }
497 }
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 }
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 }
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 }
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 }
537 void DumpWriter::seek_to_offset(jlong off) {
538 assert(off >= 0, "bad offset");
540 // need to flush before seeking
541 flush();
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 }
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 }
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 }
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 }
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 }
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 }
586 void DumpWriter::write_id(u4 x) {
587 #ifdef _LP64
588 write_u8((u8) x);
589 #else
590 write_u4(x);
591 #endif
592 }
594 // We use java mirror as the class ID
595 void DumpWriter::write_classID(Klass* k) {
596 write_objectID(k->java_mirror());
597 }
601 // Support class with a collection of functions used when dumping the heap
603 class DumperSupport : AllStatic {
604 public:
606 // write a header of the given type
607 static void write_header(DumpWriter* writer, hprofTag tag, u4 len);
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);
614 // returns the size of the instance of the given class
615 static u4 instance_size(Klass* k);
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);
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 };
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 }
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 }
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 }
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 }
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 }
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 }
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 }
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);
780 u4 size = 0;
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;
789 case JVM_SIGNATURE_BYTE :
790 case JVM_SIGNATURE_BOOLEAN : size += 1; break;
792 case JVM_SIGNATURE_CHAR :
793 case JVM_SIGNATURE_SHORT : size += 2; break;
795 case JVM_SIGNATURE_INT :
796 case JVM_SIGNATURE_FLOAT : size += 4; break;
798 case JVM_SIGNATURE_LONG :
799 case JVM_SIGNATURE_DOUBLE : size += 8; break;
801 default : ShouldNotReachHere();
802 }
803 }
804 }
805 return size;
806 }
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);
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++;
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 }
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 }
841 writer->write_u2(field_count);
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();
848 writer->write_symbolID(fld.name()); // name
849 writer->write_u1(sig2tag(sig)); // type
851 // value
852 int offset = fld.offset();
853 address addr = (address)ikh->java_mirror() + offset;
855 dump_field_value(writer, sig->byte_at(0), addr);
856 }
857 }
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);
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 }
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 }
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());
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();
893 dump_field_value(writer, sig->byte_at(0), addr);
894 }
895 }
896 }
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);
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 }
909 writer->write_u2(field_count);
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();
916 writer->write_symbolID(fld.name()); // name
917 writer->write_u1(sig2tag(sig)); // type
918 }
919 }
920 }
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();
926 writer->write_u1(HPROF_GC_INSTANCE_DUMP);
927 writer->write_objectID(o);
928 writer->write_u4(STACK_TRACE_ID);
930 // class ID
931 writer->write_classID(k);
933 // number of bytes that follow
934 writer->write_u4(instance_size(k) );
936 // field values
937 dump_instance_fields(writer, o);
938 }
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;
947 writer->write_u1(HPROF_GC_CLASS_DUMP);
949 // class ID
950 writer->write_classID(ik);
951 writer->write_u4(STACK_TRACE_ID);
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 }
961 writer->write_objectID(ik->class_loader());
962 writer->write_objectID(ik->signers());
963 writer->write_objectID(ik->protection_domain());
965 // reserved
966 writer->write_objectID(oop(NULL));
967 writer->write_objectID(oop(NULL));
969 // instance size
970 writer->write_u4(DumperSupport::instance_size(k));
972 // size of constant pool - ignored by HAT 1.1
973 writer->write_u2(0);
975 // number of static fields
976 dump_static_fields(writer, k);
978 // description of instance fields
979 dump_instance_field_descriptors(writer, k);
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");
987 writer->write_u1(HPROF_GC_CLASS_DUMP);
988 writer->write_classID(klass);
989 writer->write_u4(STACK_TRACE_ID);
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);
996 writer->write_objectID(ik->class_loader());
997 writer->write_objectID(ik->signers());
998 writer->write_objectID(ik->protection_domain());
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
1007 // get the array class for the next rank
1008 k = klass->array_klass_or_null();
1009 }
1010 }
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;
1019 writer->write_u1(HPROF_GC_CLASS_DUMP);
1020 writer->write_classID(klass);
1021 writer->write_u4(STACK_TRACE_ID);
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);
1028 writer->write_objectID(oop(NULL)); // loader
1029 writer->write_objectID(oop(NULL)); // signers
1030 writer->write_objectID(oop(NULL)); // protection domain
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
1039 // get the array class for the next rank
1040 k = klass->array_klass_or_null();
1041 }
1042 }
1044 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1045 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) {
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());
1052 // array class ID
1053 writer->write_classID(array->klass());
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 }
1062 #define WRITE_ARRAY(Array, Type, Size) \
1063 for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); }
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();
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));
1076 // nothing to copy
1077 if (array->length() == 0) {
1078 return;
1079 }
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);
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 }
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.
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 }
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 }
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
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 }
1175 // Support class used to generate HPROF_UTF8 records from the entries in the
1176 // SymbolTable.
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 };
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 }
1199 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
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 };
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 }
1231 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
1233 class JNIGlobalsDumper : public OopClosure {
1234 private:
1235 DumpWriter* _writer;
1236 DumpWriter* writer() const { return _writer; }
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 };
1246 void JNIGlobalsDumper::do_oop(oop* obj_p) {
1247 oop o = *obj_p;
1249 // ignore these
1250 if (o == NULL || o == JNIHandles::deleted_handle()) return;
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 };
1261 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records
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 };
1279 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
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 };
1299 class VM_HeapDumper;
1301 // Support class using when iterating over the heap.
1303 class HeapObjectDumper : public ObjectClosure {
1304 private:
1305 VM_HeapDumper* _dumper;
1306 DumpWriter* _writer;
1308 VM_HeapDumper* dumper() { return _dumper; }
1309 DumpWriter* writer() { return _writer; }
1311 // used to indicate that a record has been writen
1312 void mark_end_of_record();
1314 public:
1315 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) {
1316 _dumper = dumper;
1317 _writer = writer;
1318 }
1320 // called for each object in the heap
1321 void do_object(oop o);
1322 };
1324 void HeapObjectDumper::do_object(oop o) {
1325 // hide the sentinel for deleted handles
1326 if (o == JNIHandles::deleted_handle()) return;
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 }
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 }
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;
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; }
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);
1384 bool skip_operation() const;
1386 // writes a HPROF_LOAD_CLASS record
1387 static void do_load_class(Klass* k);
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);
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);
1397 // HPROF_GC_ROOT_THREAD_OBJ records
1398 int do_thread(JavaThread* thread, u4 thread_serial_num);
1399 void do_threads();
1401 void add_class_serial_number(Klass* k, int serial_num) {
1402 _klass_map->at_put_grow(serial_num, k);
1403 }
1405 // HPROF_TRACE and HPROF_FRAME records
1406 void dump_stack_traces();
1408 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record
1409 void write_dump_header();
1411 // fixes up the length of the current dump record
1412 void write_current_dump_record_length();
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();
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 }
1454 VMOp_Type type() const { return VMOp_HeapDumper; }
1455 // used to mark sub-record boundary
1456 void check_segment_length();
1457 void doit();
1458 };
1460 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL;
1461 DumpWriter* VM_HeapDumper::_global_writer = NULL;
1463 bool VM_HeapDumper::skip_operation() const {
1464 return false;
1465 }
1467 // sets the dump starting position
1468 void VM_HeapDumper::set_dump_start(jlong pos) {
1469 _dump_start = pos;
1470 }
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
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 }
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");
1493 // calculate the size of the dump record
1494 julong dump_end = writer()->current_offset();
1495 julong dump_len = (dump_end - dump_start() - 4);
1497 // record length must fit in a u4
1498 if (dump_len > max_juint) {
1499 warning("record is too large");
1500 }
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);
1506 // adjust the total size written to keep the bytes written correct.
1507 writer()->adjust_bytes_written(-((jlong) sizeof(u4)));
1509 // seek to dump end so we can continue
1510 writer()->seek_to_offset(dump_end);
1512 // no current dump record
1513 set_dump_start((jlong)-1);
1514 }
1515 }
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");
1528 if (dump_len > HeapDumpSegmentSize) {
1529 write_current_dump_record_length();
1530 write_dump_header();
1531 }
1532 }
1533 }
1534 }
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();
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 }
1551 // marks sub-record boundary
1552 void HeapObjectDumper::mark_end_of_record() {
1553 dumper()->check_segment_length();
1554 }
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;
1561 // len of HPROF_LOAD_CLASS record
1562 u4 remaining = 2*oopSize + 2*sizeof(u4);
1564 // write a HPROF_LOAD_CLASS for the class and each array class
1565 do {
1566 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
1568 // class serial number is just a number
1569 writer()->write_u4(++class_serial_num);
1571 // class ID
1572 Klass* klass = k;
1573 writer()->write_classID(klass);
1575 // add the Klass* and class serial number pair
1576 dumper()->add_class_serial_number(klass, class_serial_num);
1578 writer()->write_u4(STACK_TRACE_ID);
1580 // class name ID
1581 Symbol* name = klass->name();
1582 writer()->write_symbolID(name);
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 }
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 }
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 }
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);
1610 oop threadObj = java_thread->threadObj();
1611 assert(threadObj != NULL, "sanity check");
1613 int stack_depth = 0;
1614 if (java_thread->has_last_Java_frame()) {
1616 // vframes are resource allocated
1617 Thread* current_thread = Thread::current();
1618 ResourceMark rm(current_thread);
1619 HandleMark hm(current_thread);
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;
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()) {
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)();
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;
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 }
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 }
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.
1728 void VM_HeapDumper::doit() {
1730 HandleMark hm;
1731 CollectedHeap* ch = Universe::heap();
1733 ch->ensure_parsability(false); // must happen, even if collection does
1734 // not happen (e.g. due to GC_locker)
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 }
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();
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 }
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());
1765 // HPROF_UTF8 records
1766 SymbolTableDumper sym_dumper(writer());
1767 SymbolTable::symbols_do(&sym_dumper);
1769 // write HPROF_LOAD_CLASS records
1770 ClassLoaderDataGraph::classes_do(&do_load_class);
1771 Universe::basic_type_classes_do(&do_load_class);
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();
1777 // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT
1778 write_dump_header();
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();
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);
1794 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
1795 do_threads();
1796 check_segment_length();
1798 // HPROF_GC_ROOT_MONITOR_USED
1799 MonitorUsedDumper mon_dumper(writer());
1800 ObjectSynchronizer::oops_do(&mon_dumper);
1801 check_segment_length();
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();
1810 // HPROF_GC_ROOT_STICKY_CLASS
1811 StickyClassDumper class_dumper(writer());
1812 SystemDictionary::always_strong_classes_do(&class_dumper);
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();
1818 // Now we clear the global variables, so that a future dumper might run.
1819 clear_global_dumper();
1820 clear_global_writer();
1821 }
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
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;
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;
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 }
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");
1882 // print message in interactive case
1883 if (print_to_tty()) {
1884 tty->print_cr("Dumping heap to %s ...", path);
1885 timer()->start();
1886 }
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 }
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 }
1908 // close dump file and record any error that the writer may have encountered
1909 writer.close();
1910 set_error(writer.error());
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 }
1923 return (writer.error() == NULL) ? 0 : -1;
1924 }
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 }
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 }
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 }
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 }
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 }
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;
1980 const char* dump_file_name = "java_pid";
1981 const char* dump_file_ext = ".hprof";
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 }
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
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 }
