1 /*
2 * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "gc/shared/gcLocker.inline.hpp"
30 #include "gc/shared/genCollectedHeap.hpp"
31 #include "gc/shared/vmGCOperations.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "memory/universe.hpp"
34 #include "oops/objArrayKlass.hpp"
35 #include "oops/objArrayOop.inline.hpp"
36 #include "oops/oop.inline.hpp"
37 #include "runtime/javaCalls.hpp"
38 #include "runtime/jniHandles.hpp"
39 #include "runtime/os.hpp"
40 #include "runtime/reflectionUtils.hpp"
41 #include "runtime/vframe.hpp"
42 #include "runtime/vmThread.hpp"
43 #include "runtime/vm_operations.hpp"
44 #include "services/heapDumper.hpp"
45 #include "services/threadService.hpp"
46 #include "utilities/macros.hpp"
47 #include "utilities/ostream.hpp"
48
49 /*
50 * HPROF binary format - description copied from:
51 * src/share/demo/jvmti/hprof/hprof_io.c
52 *
53 *
54 * header "JAVA PROFILE 1.0.2" (0-terminated)
55 *
56 * u4 size of identifiers. Identifiers are used to represent
57 * UTF8 strings, objects, stack traces, etc. They usually
58 * have the same size as host pointers. For example, on
59 * Solaris and Win32, the size is 4.
60 * u4 high word
61 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70
62 * [record]* a sequence of records.
63 *
64 *
65 * Record format:
66 *
67 * u1 a TAG denoting the type of the record
68 * u4 number of *microseconds* since the time stamp in the
69 * header. (wraps around in a little more than an hour)
70 * u4 number of bytes *remaining* in the record. Note that
71 * this number excludes the tag and the length field itself.
72 * [u1]* BODY of the record (a sequence of bytes)
73 *
74 *
75 * The following TAGs are supported:
76 *
77 * TAG BODY notes
78 *----------------------------------------------------------
79 * HPROF_UTF8 a UTF8-encoded name
80 *
81 * id name ID
82 * [u1]* UTF8 characters (no trailing zero)
83 *
84 * HPROF_LOAD_CLASS a newly loaded class
85 *
86 * u4 class serial number (> 0)
87 * id class object ID
88 * u4 stack trace serial number
89 * id class name ID
90 *
91 * HPROF_UNLOAD_CLASS an unloading class
92 *
93 * u4 class serial_number
94 *
95 * HPROF_FRAME a Java stack frame
96 *
97 * id stack frame ID
98 * id method name ID
99 * id method signature ID
100 * id source file name ID
101 * u4 class serial number
102 * i4 line number. >0: normal
103 * -1: unknown
104 * -2: compiled method
105 * -3: native method
106 *
107 * HPROF_TRACE a Java stack trace
108 *
109 * u4 stack trace serial number
110 * u4 thread serial number
111 * u4 number of frames
112 * [id]* stack frame IDs
113 *
114 *
115 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC
116 *
117 * u2 flags 0x0001: incremental vs. complete
118 * 0x0002: sorted by allocation vs. live
119 * 0x0004: whether to force a GC
120 * u4 cutoff ratio
121 * u4 total live bytes
122 * u4 total live instances
123 * u8 total bytes allocated
124 * u8 total instances allocated
125 * u4 number of sites that follow
126 * [u1 is_array: 0: normal object
127 * 2: object array
128 * 4: boolean array
129 * 5: char array
130 * 6: float array
131 * 7: double array
132 * 8: byte array
133 * 9: short array
134 * 10: int array
135 * 11: long array
136 * u4 class serial number (may be zero during startup)
137 * u4 stack trace serial number
138 * u4 number of bytes alive
139 * u4 number of instances alive
140 * u4 number of bytes allocated
141 * u4]* number of instance allocated
142 *
143 * HPROF_START_THREAD a newly started thread.
144 *
145 * u4 thread serial number (> 0)
146 * id thread object ID
147 * u4 stack trace serial number
148 * id thread name ID
149 * id thread group name ID
150 * id thread group parent name ID
151 *
152 * HPROF_END_THREAD a terminating thread.
153 *
154 * u4 thread serial number
155 *
156 * HPROF_HEAP_SUMMARY heap summary
157 *
158 * u4 total live bytes
159 * u4 total live instances
160 * u8 total bytes allocated
161 * u8 total instances allocated
162 *
163 * HPROF_HEAP_DUMP denote a heap dump
164 *
165 * [heap dump sub-records]*
166 *
167 * There are four kinds of heap dump sub-records:
168 *
169 * u1 sub-record type
170 *
171 * HPROF_GC_ROOT_UNKNOWN unknown root
172 *
173 * id object ID
174 *
175 * HPROF_GC_ROOT_THREAD_OBJ thread object
176 *
177 * id thread object ID (may be 0 for a
178 * thread newly attached through JNI)
179 * u4 thread sequence number
180 * u4 stack trace sequence number
181 *
182 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root
183 *
184 * id object ID
185 * id JNI global ref ID
186 *
187 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref
188 *
189 * id object ID
190 * u4 thread serial number
191 * u4 frame # in stack trace (-1 for empty)
192 *
193 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame
194 *
195 * id object ID
196 * u4 thread serial number
197 * u4 frame # in stack trace (-1 for empty)
198 *
199 * HPROF_GC_ROOT_NATIVE_STACK Native stack
200 *
201 * id object ID
202 * u4 thread serial number
203 *
204 * HPROF_GC_ROOT_STICKY_CLASS System class
205 *
206 * id object ID
207 *
208 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block
209 *
210 * id object ID
211 * u4 thread serial number
212 *
213 * HPROF_GC_ROOT_MONITOR_USED Busy monitor
214 *
215 * id object ID
216 *
217 * HPROF_GC_CLASS_DUMP dump of a class object
218 *
219 * id class object ID
220 * u4 stack trace serial number
221 * id super class object ID
222 * id class loader object ID
223 * id signers object ID
224 * id protection domain object ID
225 * id reserved
226 * id reserved
227 *
228 * u4 instance size (in bytes)
229 *
230 * u2 size of constant pool
231 * [u2, constant pool index,
232 * ty, type
233 * 2: object
234 * 4: boolean
235 * 5: char
236 * 6: float
237 * 7: double
238 * 8: byte
239 * 9: short
240 * 10: int
241 * 11: long
242 * vl]* and value
243 *
244 * u2 number of static fields
245 * [id, static field name,
246 * ty, type,
247 * vl]* and value
248 *
249 * u2 number of inst. fields (not inc. super)
250 * [id, instance field name,
251 * ty]* type
252 *
253 * HPROF_GC_INSTANCE_DUMP dump of a normal object
254 *
255 * id object ID
256 * u4 stack trace serial number
257 * id class object ID
258 * u4 number of bytes that follow
259 * [vl]* instance field values (class, followed
260 * by super, super's super ...)
261 *
262 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array
263 *
264 * id array object ID
265 * u4 stack trace serial number
266 * u4 number of elements
267 * id array class ID
268 * [id]* elements
269 *
270 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array
271 *
272 * id array object ID
273 * u4 stack trace serial number
274 * u4 number of elements
275 * u1 element type
276 * 4: boolean array
277 * 5: char array
278 * 6: float array
279 * 7: double array
280 * 8: byte array
281 * 9: short array
282 * 10: int array
283 * 11: long array
284 * [u1]* elements
285 *
286 * HPROF_CPU_SAMPLES a set of sample traces of running threads
287 *
288 * u4 total number of samples
289 * u4 # of traces
290 * [u4 # of samples
291 * u4]* stack trace serial number
292 *
293 * HPROF_CONTROL_SETTINGS the settings of on/off switches
294 *
295 * u4 0x00000001: alloc traces on/off
296 * 0x00000002: cpu sampling on/off
297 * u2 stack trace depth
298 *
299 *
300 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
301 * be generated as a sequence of heap dump segments. This sequence is
302 * terminated by an end record. The additional tags allowed by format
303 * "JAVA PROFILE 1.0.2" are:
304 *
305 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
306 *
307 * [heap dump sub-records]*
308 * The same sub-record types allowed by HPROF_HEAP_DUMP
309 *
310 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
311 *
312 */
313
314
315 // HPROF tags
316
317 typedef enum {
318 // top-level records
319 HPROF_UTF8 = 0x01,
320 HPROF_LOAD_CLASS = 0x02,
321 HPROF_UNLOAD_CLASS = 0x03,
322 HPROF_FRAME = 0x04,
323 HPROF_TRACE = 0x05,
324 HPROF_ALLOC_SITES = 0x06,
325 HPROF_HEAP_SUMMARY = 0x07,
326 HPROF_START_THREAD = 0x0A,
327 HPROF_END_THREAD = 0x0B,
328 HPROF_HEAP_DUMP = 0x0C,
329 HPROF_CPU_SAMPLES = 0x0D,
330 HPROF_CONTROL_SETTINGS = 0x0E,
331
332 // 1.0.2 record types
333 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
334 HPROF_HEAP_DUMP_END = 0x2C,
335
336 // field types
337 HPROF_ARRAY_OBJECT = 0x01,
338 HPROF_NORMAL_OBJECT = 0x02,
339 HPROF_BOOLEAN = 0x04,
340 HPROF_CHAR = 0x05,
341 HPROF_FLOAT = 0x06,
342 HPROF_DOUBLE = 0x07,
343 HPROF_BYTE = 0x08,
344 HPROF_SHORT = 0x09,
345 HPROF_INT = 0x0A,
346 HPROF_LONG = 0x0B,
347
348 // data-dump sub-records
349 HPROF_GC_ROOT_UNKNOWN = 0xFF,
350 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
351 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
352 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
353 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
354 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
355 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
356 HPROF_GC_ROOT_MONITOR_USED = 0x07,
357 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
358 HPROF_GC_CLASS_DUMP = 0x20,
359 HPROF_GC_INSTANCE_DUMP = 0x21,
360 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
361 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
362 } hprofTag;
363
364 // Default stack trace ID (used for dummy HPROF_TRACE record)
365 enum {
366 STACK_TRACE_ID = 1,
367 INITIAL_CLASS_COUNT = 200
368 };
369
370 // Supports I/O operations on a dump file
371
372 class DumpWriter : public StackObj {
373 private:
374 enum {
375 io_buffer_size = 8*M
376 };
377
378 int _fd; // file descriptor (-1 if dump file not open)
379 julong _bytes_written; // number of byte written to dump file
380
381 char* _buffer; // internal buffer
382 size_t _size;
383 size_t _pos;
384
385 jlong _dump_start;
386
387 char* _error; // error message when I/O fails
388
389 void set_file_descriptor(int fd) { _fd = fd; }
390 int file_descriptor() const { return _fd; }
391
392 char* buffer() const { return _buffer; }
393 size_t buffer_size() const { return _size; }
394 size_t position() const { return _pos; }
395 void set_position(size_t pos) { _pos = pos; }
396
397 void set_error(const char* error) { _error = (char*)os::strdup(error); }
398
399 // all I/O go through this function
400 void write_internal(void* s, size_t len);
401
402 public:
403 DumpWriter(const char* path);
404 ~DumpWriter();
405
406 void close();
407 bool is_open() const { return file_descriptor() >= 0; }
408 void flush();
409
410 jlong dump_start() const { return _dump_start; }
411 void set_dump_start(jlong pos);
412 julong current_record_length();
413
414 // total number of bytes written to the disk
415 julong bytes_written() const { return _bytes_written; }
416
417 // adjust the number of bytes written to disk (used to keep the count
418 // of the number of bytes written in case of rewrites)
419 void adjust_bytes_written(jlong n) { _bytes_written += n; }
420
421 // number of (buffered) bytes as yet unwritten to the dump file
422 size_t bytes_unwritten() const { return position(); }
423
424 char* error() const { return _error; }
425
426 jlong current_offset();
427 void seek_to_offset(jlong pos);
428
429 // writer functions
430 void write_raw(void* s, size_t len);
431 void write_u1(u1 x) { write_raw((void*)&x, 1); }
432 void write_u2(u2 x);
433 void write_u4(u4 x);
434 void write_u8(u8 x);
435 void write_objectID(oop o);
436 void write_symbolID(Symbol* o);
437 void write_classID(Klass* k);
438 void write_id(u4 x);
439 };
440
441 DumpWriter::DumpWriter(const char* path) {
442 // try to allocate an I/O buffer of io_buffer_size. If there isn't
443 // sufficient memory then reduce size until we can allocate something.
444 _size = io_buffer_size;
445 do {
446 _buffer = (char*)os::malloc(_size, mtInternal);
447 if (_buffer == NULL) {
448 _size = _size >> 1;
449 }
450 } while (_buffer == NULL && _size > 0);
451 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check");
452 _pos = 0;
453 _error = NULL;
454 _bytes_written = 0L;
455 _dump_start = (jlong)-1;
456 _fd = os::create_binary_file(path, false); // don't replace existing file
457
458 // if the open failed we record the error
459 if (_fd < 0) {
460 _error = (char*)os::strdup(os::strerror(errno));
461 }
462 }
463
464 DumpWriter::~DumpWriter() {
465 // flush and close dump file
466 if (is_open()) {
467 close();
468 }
469 if (_buffer != NULL) os::free(_buffer);
470 if (_error != NULL) os::free(_error);
471 }
472
473 // closes dump file (if open)
474 void DumpWriter::close() {
475 // flush and close dump file
476 if (is_open()) {
477 flush();
478 os::close(file_descriptor());
479 set_file_descriptor(-1);
480 }
481 }
482
483 // sets the dump starting position
484 void DumpWriter::set_dump_start(jlong pos) {
485 _dump_start = pos;
486 }
487
488 julong DumpWriter::current_record_length() {
489 if (is_open()) {
490 // calculate the size of the dump record
491 julong dump_end = bytes_written() + bytes_unwritten();
492 assert(dump_end == (size_t)current_offset(), "checking");
493 julong dump_len = dump_end - dump_start() - 4;
494 return dump_len;
495 }
496 return 0;
497 }
498
499 // write directly to the file
500 void DumpWriter::write_internal(void* s, size_t len) {
501 if (is_open()) {
502 const char* pos = (char*)s;
503 ssize_t n = 0;
504 while (len > 0) {
505 uint tmp = (uint)MIN2(len, (size_t)UINT_MAX);
506 n = os::write(file_descriptor(), pos, tmp);
507
508 if (n < 0) {
509 // EINTR cannot happen here, os::write will take care of that
510 set_error(os::strerror(errno));
511 os::close(file_descriptor());
512 set_file_descriptor(-1);
513 return;
514 }
515
516 _bytes_written += n;
517 pos += n;
518 len -= n;
519 }
520 }
521 }
522
523 // write raw bytes
524 void DumpWriter::write_raw(void* s, size_t len) {
525 if (is_open()) {
526 // flush buffer to make room
527 if ((position() + len) >= buffer_size()) {
528 flush();
529 }
530
531 // buffer not available or too big to buffer it
532 if ((buffer() == NULL) || (len >= buffer_size())) {
533 write_internal(s, len);
534 } else {
535 // Should optimize this for u1/u2/u4/u8 sizes.
536 memcpy(buffer() + position(), s, len);
537 set_position(position() + len);
538 }
539 }
540 }
541
542 // flush any buffered bytes to the file
543 void DumpWriter::flush() {
544 if (is_open() && position() > 0) {
545 write_internal(buffer(), position());
546 set_position(0);
547 }
548 }
549
550 jlong DumpWriter::current_offset() {
551 if (is_open()) {
552 // the offset is the file offset plus whatever we have buffered
553 jlong offset = os::current_file_offset(file_descriptor());
554 assert(offset >= 0, "lseek failed");
555 return offset + position();
556 } else {
557 return (jlong)-1;
558 }
559 }
560
561 void DumpWriter::seek_to_offset(jlong off) {
562 assert(off >= 0, "bad offset");
563
564 // need to flush before seeking
565 flush();
566
567 // may be closed due to I/O error
568 if (is_open()) {
569 jlong n = os::seek_to_file_offset(file_descriptor(), off);
570 assert(n >= 0, "lseek failed");
571 }
572 }
573
574 void DumpWriter::write_u2(u2 x) {
575 u2 v;
576 Bytes::put_Java_u2((address)&v, x);
577 write_raw((void*)&v, 2);
578 }
579
580 void DumpWriter::write_u4(u4 x) {
581 u4 v;
582 Bytes::put_Java_u4((address)&v, x);
583 write_raw((void*)&v, 4);
584 }
585
586 void DumpWriter::write_u8(u8 x) {
587 u8 v;
588 Bytes::put_Java_u8((address)&v, x);
589 write_raw((void*)&v, 8);
590 }
591
592 void DumpWriter::write_objectID(oop o) {
593 address a = (address)o;
594 #ifdef _LP64
595 write_u8((u8)a);
596 #else
597 write_u4((u4)a);
598 #endif
599 }
600
601 void DumpWriter::write_symbolID(Symbol* s) {
602 address a = (address)((uintptr_t)s);
603 #ifdef _LP64
604 write_u8((u8)a);
605 #else
606 write_u4((u4)a);
607 #endif
608 }
609
610 void DumpWriter::write_id(u4 x) {
611 #ifdef _LP64
612 write_u8((u8) x);
613 #else
614 write_u4(x);
615 #endif
616 }
617
618 // We use java mirror as the class ID
619 void DumpWriter::write_classID(Klass* k) {
620 write_objectID(k->java_mirror());
621 }
622
623
624
625 // Support class with a collection of functions used when dumping the heap
626
627 class DumperSupport : AllStatic {
628 public:
629
630 // write a header of the given type
631 static void write_header(DumpWriter* writer, hprofTag tag, u4 len);
632
633 // returns hprof tag for the given type signature
634 static hprofTag sig2tag(Symbol* sig);
635 // returns hprof tag for the given basic type
636 static hprofTag type2tag(BasicType type);
637
638 // returns the size of the instance of the given class
639 static u4 instance_size(Klass* k);
640
641 // dump a jfloat
642 static void dump_float(DumpWriter* writer, jfloat f);
643 // dump a jdouble
644 static void dump_double(DumpWriter* writer, jdouble d);
645 // dumps the raw value of the given field
646 static void dump_field_value(DumpWriter* writer, char type, address addr);
647 // dumps static fields of the given class
648 static void dump_static_fields(DumpWriter* writer, Klass* k);
649 // dump the raw values of the instance fields of the given object
650 static void dump_instance_fields(DumpWriter* writer, oop o);
651 // dumps the definition of the instance fields for a given class
652 static void dump_instance_field_descriptors(DumpWriter* writer, Klass* k);
653 // creates HPROF_GC_INSTANCE_DUMP record for the given object
654 static void dump_instance(DumpWriter* writer, oop o);
655 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its
656 // array classes
657 static void dump_class_and_array_classes(DumpWriter* writer, Klass* k);
658 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
659 // class (and each multi-dimensional array class too)
660 static void dump_basic_type_array_class(DumpWriter* writer, Klass* k);
661
662 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
663 static void dump_object_array(DumpWriter* writer, objArrayOop array);
664 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
665 static void dump_prim_array(DumpWriter* writer, typeArrayOop array);
666 // create HPROF_FRAME record for the given method and bci
667 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
668
669 // check if we need to truncate an array
670 static int calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size);
671
672 // writes a HPROF_HEAP_DUMP_SEGMENT record
673 static void write_dump_header(DumpWriter* writer);
674
675 // fixes up the length of the current dump record
676 static void write_current_dump_record_length(DumpWriter* writer);
677
678 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
679 static void end_of_dump(DumpWriter* writer);
680 };
681
682 // write a header of the given type
683 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) {
684 writer->write_u1((u1)tag);
685 writer->write_u4(0); // current ticks
686 writer->write_u4(len);
687 }
688
689 // returns hprof tag for the given type signature
690 hprofTag DumperSupport::sig2tag(Symbol* sig) {
691 switch (sig->byte_at(0)) {
692 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT;
693 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT;
694 case JVM_SIGNATURE_BYTE : return HPROF_BYTE;
695 case JVM_SIGNATURE_CHAR : return HPROF_CHAR;
696 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT;
697 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE;
698 case JVM_SIGNATURE_INT : return HPROF_INT;
699 case JVM_SIGNATURE_LONG : return HPROF_LONG;
700 case JVM_SIGNATURE_SHORT : return HPROF_SHORT;
701 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN;
702 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
703 }
704 }
705
706 hprofTag DumperSupport::type2tag(BasicType type) {
707 switch (type) {
708 case T_BYTE : return HPROF_BYTE;
709 case T_CHAR : return HPROF_CHAR;
710 case T_FLOAT : return HPROF_FLOAT;
711 case T_DOUBLE : return HPROF_DOUBLE;
712 case T_INT : return HPROF_INT;
713 case T_LONG : return HPROF_LONG;
714 case T_SHORT : return HPROF_SHORT;
715 case T_BOOLEAN : return HPROF_BOOLEAN;
716 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
717 }
718 }
719
720 // dump a jfloat
721 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) {
722 if (g_isnan(f)) {
723 writer->write_u4(0x7fc00000); // collapsing NaNs
724 } else {
725 union {
726 int i;
727 float f;
728 } u;
729 u.f = (float)f;
730 writer->write_u4((u4)u.i);
731 }
732 }
733
734 // dump a jdouble
735 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) {
736 union {
737 jlong l;
738 double d;
739 } u;
740 if (g_isnan(d)) { // collapsing NaNs
741 u.l = (jlong)(0x7ff80000);
742 u.l = (u.l << 32);
743 } else {
744 u.d = (double)d;
745 }
746 writer->write_u8((u8)u.l);
747 }
748
749 // dumps the raw value of the given field
750 void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) {
751 switch (type) {
752 case JVM_SIGNATURE_CLASS :
753 case JVM_SIGNATURE_ARRAY : {
754 oop o;
755 if (UseCompressedOops) {
756 o = oopDesc::load_decode_heap_oop((narrowOop*)addr);
757 } else {
758 o = oopDesc::load_decode_heap_oop((oop*)addr);
759 }
760
761 // reflection and Unsafe classes may have a reference to a
762 // Klass* so filter it out.
763 assert(o->is_oop_or_null(), "Expected an oop or NULL at " PTR_FORMAT, p2i(o));
764 writer->write_objectID(o);
765 break;
766 }
767 case JVM_SIGNATURE_BYTE : {
768 jbyte* b = (jbyte*)addr;
769 writer->write_u1((u1)*b);
770 break;
771 }
772 case JVM_SIGNATURE_CHAR : {
773 jchar* c = (jchar*)addr;
774 writer->write_u2((u2)*c);
775 break;
776 }
777 case JVM_SIGNATURE_SHORT : {
778 jshort* s = (jshort*)addr;
779 writer->write_u2((u2)*s);
780 break;
781 }
782 case JVM_SIGNATURE_FLOAT : {
783 jfloat* f = (jfloat*)addr;
784 dump_float(writer, *f);
785 break;
786 }
787 case JVM_SIGNATURE_DOUBLE : {
788 jdouble* f = (jdouble*)addr;
789 dump_double(writer, *f);
790 break;
791 }
792 case JVM_SIGNATURE_INT : {
793 jint* i = (jint*)addr;
794 writer->write_u4((u4)*i);
795 break;
796 }
797 case JVM_SIGNATURE_LONG : {
798 jlong* l = (jlong*)addr;
799 writer->write_u8((u8)*l);
800 break;
801 }
802 case JVM_SIGNATURE_BOOLEAN : {
803 jboolean* b = (jboolean*)addr;
804 writer->write_u1((u1)*b);
805 break;
806 }
807 default : ShouldNotReachHere();
808 }
809 }
810
811 // returns the size of the instance of the given class
812 u4 DumperSupport::instance_size(Klass* k) {
813 HandleMark hm;
814 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
815
816 u4 size = 0;
817
818 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
819 if (!fld.access_flags().is_static()) {
820 Symbol* sig = fld.signature();
821 switch (sig->byte_at(0)) {
822 case JVM_SIGNATURE_CLASS :
823 case JVM_SIGNATURE_ARRAY : size += oopSize; break;
824
825 case JVM_SIGNATURE_BYTE :
826 case JVM_SIGNATURE_BOOLEAN : size += 1; break;
827
828 case JVM_SIGNATURE_CHAR :
829 case JVM_SIGNATURE_SHORT : size += 2; break;
830
831 case JVM_SIGNATURE_INT :
832 case JVM_SIGNATURE_FLOAT : size += 4; break;
833
834 case JVM_SIGNATURE_LONG :
835 case JVM_SIGNATURE_DOUBLE : size += 8; break;
836
837 default : ShouldNotReachHere();
838 }
839 }
840 }
841 return size;
842 }
843
844 // dumps static fields of the given class
845 void DumperSupport::dump_static_fields(DumpWriter* writer, Klass* k) {
846 HandleMark hm;
847 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
848
849 // pass 1 - count the static fields
850 u2 field_count = 0;
851 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
852 if (fldc.access_flags().is_static()) field_count++;
853 }
854
855 writer->write_u2(field_count);
856
857 // pass 2 - dump the field descriptors and raw values
858 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
859 if (fld.access_flags().is_static()) {
860 Symbol* sig = fld.signature();
861
862 writer->write_symbolID(fld.name()); // name
863 writer->write_u1(sig2tag(sig)); // type
864
865 // value
866 int offset = fld.offset();
867 address addr = (address)ikh->java_mirror() + offset;
868
869 dump_field_value(writer, sig->byte_at(0), addr);
870 }
871 }
872 }
873
874 // dump the raw values of the instance fields of the given object
875 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) {
876 HandleMark hm;
877 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass());
878
879 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
880 if (!fld.access_flags().is_static()) {
881 Symbol* sig = fld.signature();
882 address addr = (address)o + fld.offset();
883
884 dump_field_value(writer, sig->byte_at(0), addr);
885 }
886 }
887 }
888
889 // dumps the definition of the instance fields for a given class
890 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, Klass* k) {
891 HandleMark hm;
892 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
893
894 // pass 1 - count the instance fields
895 u2 field_count = 0;
896 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
897 if (!fldc.access_flags().is_static()) field_count++;
898 }
899
900 writer->write_u2(field_count);
901
902 // pass 2 - dump the field descriptors
903 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
904 if (!fld.access_flags().is_static()) {
905 Symbol* sig = fld.signature();
906
907 writer->write_symbolID(fld.name()); // name
908 writer->write_u1(sig2tag(sig)); // type
909 }
910 }
911 }
912
913 // creates HPROF_GC_INSTANCE_DUMP record for the given object
914 void DumperSupport::dump_instance(DumpWriter* writer, oop o) {
915 Klass* k = o->klass();
916
917 writer->write_u1(HPROF_GC_INSTANCE_DUMP);
918 writer->write_objectID(o);
919 writer->write_u4(STACK_TRACE_ID);
920
921 // class ID
922 writer->write_classID(k);
923
924 // number of bytes that follow
925 writer->write_u4(instance_size(k) );
926
927 // field values
928 dump_instance_fields(writer, o);
929 }
930
931 // creates HPROF_GC_CLASS_DUMP record for the given class and each of
932 // its array classes
933 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, Klass* k) {
934 InstanceKlass* ik = InstanceKlass::cast(k);
935
936 // We can safepoint and do a heap dump at a point where we have a Klass,
937 // but no java mirror class has been setup for it. So we need to check
938 // that the class is at least loaded, to avoid crash from a null mirror.
939 if (!ik->is_loaded()) {
940 return;
941 }
942
943 writer->write_u1(HPROF_GC_CLASS_DUMP);
944
945 // class ID
946 writer->write_classID(ik);
947 writer->write_u4(STACK_TRACE_ID);
948
949 // super class ID
950 Klass* java_super = ik->java_super();
951 if (java_super == NULL) {
952 writer->write_objectID(oop(NULL));
953 } else {
954 writer->write_classID(java_super);
955 }
956
957 writer->write_objectID(ik->class_loader());
958 writer->write_objectID(ik->signers());
959 writer->write_objectID(ik->protection_domain());
960
961 // reserved
962 writer->write_objectID(oop(NULL));
963 writer->write_objectID(oop(NULL));
964
965 // instance size
966 writer->write_u4(DumperSupport::instance_size(k));
967
968 // size of constant pool - ignored by HAT 1.1
969 writer->write_u2(0);
970
971 // number of static fields
972 dump_static_fields(writer, k);
973
974 // description of instance fields
975 dump_instance_field_descriptors(writer, k);
976
977 // array classes
978 k = k->array_klass_or_null();
979 while (k != NULL) {
980 Klass* klass = k;
981 assert(klass->is_objArray_klass(), "not an ObjArrayKlass");
982
983 writer->write_u1(HPROF_GC_CLASS_DUMP);
984 writer->write_classID(klass);
985 writer->write_u4(STACK_TRACE_ID);
986
987 // super class of array classes is java.lang.Object
988 java_super = klass->java_super();
989 assert(java_super != NULL, "checking");
990 writer->write_classID(java_super);
991
992 writer->write_objectID(ik->class_loader());
993 writer->write_objectID(ik->signers());
994 writer->write_objectID(ik->protection_domain());
995
996 writer->write_objectID(oop(NULL)); // reserved
997 writer->write_objectID(oop(NULL));
998 writer->write_u4(0); // instance size
999 writer->write_u2(0); // constant pool
1000 writer->write_u2(0); // static fields
1001 writer->write_u2(0); // instance fields
1002
1003 // get the array class for the next rank
1004 k = klass->array_klass_or_null();
1005 }
1006 }
1007
1008 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
1009 // class (and each multi-dimensional array class too)
1010 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, Klass* k) {
1011 // array classes
1012 while (k != NULL) {
1013 Klass* klass = k;
1014
1015 writer->write_u1(HPROF_GC_CLASS_DUMP);
1016 writer->write_classID(klass);
1017 writer->write_u4(STACK_TRACE_ID);
1018
1019 // super class of array classes is java.lang.Object
1020 Klass* java_super = klass->java_super();
1021 assert(java_super != NULL, "checking");
1022 writer->write_classID(java_super);
1023
1024 writer->write_objectID(oop(NULL)); // loader
1025 writer->write_objectID(oop(NULL)); // signers
1026 writer->write_objectID(oop(NULL)); // protection domain
1027
1028 writer->write_objectID(oop(NULL)); // reserved
1029 writer->write_objectID(oop(NULL));
1030 writer->write_u4(0); // instance size
1031 writer->write_u2(0); // constant pool
1032 writer->write_u2(0); // static fields
1033 writer->write_u2(0); // instance fields
1034
1035 // get the array class for the next rank
1036 k = klass->array_klass_or_null();
1037 }
1038 }
1039
1040 // Hprof uses an u4 as record length field,
1041 // which means we need to truncate arrays that are too long.
1042 int DumperSupport::calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size) {
1043 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1044 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
1045
1046 int length = array->length();
1047
1048 int type_size;
1049 if (type == T_OBJECT) {
1050 type_size = sizeof(address);
1051 } else {
1052 type_size = type2aelembytes(type);
1053 }
1054
1055 size_t length_in_bytes = (size_t)length * type_size;
1056
1057 // Create a new record if the current record is non-empty and the array can't fit.
1058 julong current_record_length = writer->current_record_length();
1059 if (current_record_length > 0 &&
1060 (current_record_length + header_size + length_in_bytes) > max_juint) {
1061 write_current_dump_record_length(writer);
1062 write_dump_header(writer);
1063
1064 // We now have an empty record.
1065 current_record_length = 0;
1066 }
1067
1068 // Calculate max bytes we can use.
1069 uint max_bytes = max_juint - (header_size + current_record_length);
1070
1071 // Array too long for the record?
1072 // Calculate max length and return it.
1073 if (length_in_bytes > max_bytes) {
1074 length = max_bytes / type_size;
1075 length_in_bytes = (size_t)length * type_size;
1076
1077 warning("cannot dump array of type %s[] with length %d; truncating to length %d",
1078 type2name_tab[type], array->length(), length);
1079 }
1080 return length;
1081 }
1082
1083 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1084 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) {
1085 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
1086 short header_size = 1 + 2 * 4 + 2 * sizeof(address);
1087
1088 int length = calculate_array_max_length(writer, array, header_size);
1089
1090 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP);
1091 writer->write_objectID(array);
1092 writer->write_u4(STACK_TRACE_ID);
1093 writer->write_u4(length);
1094
1095 // array class ID
1096 writer->write_classID(array->klass());
1097
1098 // [id]* elements
1099 for (int index = 0; index < length; index++) {
1100 oop o = array->obj_at(index);
1101 writer->write_objectID(o);
1102 }
1103 }
1104
1105 #define WRITE_ARRAY(Array, Type, Size, Length) \
1106 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
1107
1108 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1109 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) {
1110 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1111
1112 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID)
1113 short header_size = 2 * 1 + 2 * 4 + sizeof(address);
1114
1115 int length = calculate_array_max_length(writer, array, header_size);
1116 int type_size = type2aelembytes(type);
1117 u4 length_in_bytes = (u4)length * type_size;
1118
1119 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP);
1120 writer->write_objectID(array);
1121 writer->write_u4(STACK_TRACE_ID);
1122 writer->write_u4(length);
1123 writer->write_u1(type2tag(type));
1124
1125 // nothing to copy
1126 if (length == 0) {
1127 return;
1128 }
1129
1130 // If the byte ordering is big endian then we can copy most types directly
1131
1132 switch (type) {
1133 case T_INT : {
1134 if (Bytes::is_Java_byte_ordering_different()) {
1135 WRITE_ARRAY(array, int, u4, length);
1136 } else {
1137 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes);
1138 }
1139 break;
1140 }
1141 case T_BYTE : {
1142 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes);
1143 break;
1144 }
1145 case T_CHAR : {
1146 if (Bytes::is_Java_byte_ordering_different()) {
1147 WRITE_ARRAY(array, char, u2, length);
1148 } else {
1149 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes);
1150 }
1151 break;
1152 }
1153 case T_SHORT : {
1154 if (Bytes::is_Java_byte_ordering_different()) {
1155 WRITE_ARRAY(array, short, u2, length);
1156 } else {
1157 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes);
1158 }
1159 break;
1160 }
1161 case T_BOOLEAN : {
1162 if (Bytes::is_Java_byte_ordering_different()) {
1163 WRITE_ARRAY(array, bool, u1, length);
1164 } else {
1165 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes);
1166 }
1167 break;
1168 }
1169 case T_LONG : {
1170 if (Bytes::is_Java_byte_ordering_different()) {
1171 WRITE_ARRAY(array, long, u8, length);
1172 } else {
1173 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes);
1174 }
1175 break;
1176 }
1177
1178 // handle float/doubles in a special value to ensure than NaNs are
1179 // written correctly. TO DO: Check if we can avoid this on processors that
1180 // use IEEE 754.
1181
1182 case T_FLOAT : {
1183 for (int i = 0; i < length; i++) {
1184 dump_float(writer, array->float_at(i));
1185 }
1186 break;
1187 }
1188 case T_DOUBLE : {
1189 for (int i = 0; i < length; i++) {
1190 dump_double(writer, array->double_at(i));
1191 }
1192 break;
1193 }
1194 default : ShouldNotReachHere();
1195 }
1196 }
1197
1198 // create a HPROF_FRAME record of the given Method* and bci
1199 void DumperSupport::dump_stack_frame(DumpWriter* writer,
1200 int frame_serial_num,
1201 int class_serial_num,
1202 Method* m,
1203 int bci) {
1204 int line_number;
1205 if (m->is_native()) {
1206 line_number = -3; // native frame
1207 } else {
1208 line_number = m->line_number_from_bci(bci);
1209 }
1210
1211 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1212 writer->write_id(frame_serial_num); // frame serial number
1213 writer->write_symbolID(m->name()); // method's name
1214 writer->write_symbolID(m->signature()); // method's signature
1215
1216 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass");
1217 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1218 writer->write_u4(class_serial_num); // class serial number
1219 writer->write_u4((u4) line_number); // line number
1220 }
1221
1222
1223 // Support class used to generate HPROF_UTF8 records from the entries in the
1224 // SymbolTable.
1225
1226 class SymbolTableDumper : public SymbolClosure {
1227 private:
1228 DumpWriter* _writer;
1229 DumpWriter* writer() const { return _writer; }
1230 public:
1231 SymbolTableDumper(DumpWriter* writer) { _writer = writer; }
1232 void do_symbol(Symbol** p);
1233 };
1234
1235 void SymbolTableDumper::do_symbol(Symbol** p) {
1236 ResourceMark rm;
1237 Symbol* sym = load_symbol(p);
1238 int len = sym->utf8_length();
1239 if (len > 0) {
1240 char* s = sym->as_utf8();
1241 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1242 writer()->write_symbolID(sym);
1243 writer()->write_raw(s, len);
1244 }
1245 }
1246
1247 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
1248
1249 class JNILocalsDumper : public OopClosure {
1250 private:
1251 DumpWriter* _writer;
1252 u4 _thread_serial_num;
1253 int _frame_num;
1254 DumpWriter* writer() const { return _writer; }
1255 public:
1256 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) {
1257 _writer = writer;
1258 _thread_serial_num = thread_serial_num;
1259 _frame_num = -1; // default - empty stack
1260 }
1261 void set_frame_number(int n) { _frame_num = n; }
1262 void do_oop(oop* obj_p);
1263 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1264 };
1265
1266
1267 void JNILocalsDumper::do_oop(oop* obj_p) {
1268 // ignore null or deleted handles
1269 oop o = *obj_p;
1270 if (o != NULL && o != JNIHandles::deleted_handle()) {
1271 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL);
1272 writer()->write_objectID(o);
1273 writer()->write_u4(_thread_serial_num);
1274 writer()->write_u4((u4)_frame_num);
1275 }
1276 }
1277
1278
1279 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
1280
1281 class JNIGlobalsDumper : public OopClosure {
1282 private:
1283 DumpWriter* _writer;
1284 DumpWriter* writer() const { return _writer; }
1285
1286 public:
1287 JNIGlobalsDumper(DumpWriter* writer) {
1288 _writer = writer;
1289 }
1290 void do_oop(oop* obj_p);
1291 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1292 };
1293
1294 void JNIGlobalsDumper::do_oop(oop* obj_p) {
1295 oop o = *obj_p;
1296
1297 // ignore these
1298 if (o == NULL || o == JNIHandles::deleted_handle()) return;
1299
1300 // we ignore global ref to symbols and other internal objects
1301 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) {
1302 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL);
1303 writer()->write_objectID(o);
1304 writer()->write_objectID((oopDesc*)obj_p); // global ref ID
1305 }
1306 };
1307
1308
1309 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records
1310
1311 class MonitorUsedDumper : public OopClosure {
1312 private:
1313 DumpWriter* _writer;
1314 DumpWriter* writer() const { return _writer; }
1315 public:
1316 MonitorUsedDumper(DumpWriter* writer) {
1317 _writer = writer;
1318 }
1319 void do_oop(oop* obj_p) {
1320 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED);
1321 writer()->write_objectID(*obj_p);
1322 }
1323 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1324 };
1325
1326
1327 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
1328
1329 class StickyClassDumper : public KlassClosure {
1330 private:
1331 DumpWriter* _writer;
1332 DumpWriter* writer() const { return _writer; }
1333 public:
1334 StickyClassDumper(DumpWriter* writer) {
1335 _writer = writer;
1336 }
1337 void do_klass(Klass* k) {
1338 if (k->is_instance_klass()) {
1339 InstanceKlass* ik = InstanceKlass::cast(k);
1340 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS);
1341 writer()->write_classID(ik);
1342 }
1343 }
1344 };
1345
1346
1347 class VM_HeapDumper;
1348
1349 // Support class using when iterating over the heap.
1350
1351 class HeapObjectDumper : public ObjectClosure {
1352 private:
1353 VM_HeapDumper* _dumper;
1354 DumpWriter* _writer;
1355
1356 VM_HeapDumper* dumper() { return _dumper; }
1357 DumpWriter* writer() { return _writer; }
1358
1359 // used to indicate that a record has been writen
1360 void mark_end_of_record();
1361
1362 public:
1363 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) {
1364 _dumper = dumper;
1365 _writer = writer;
1366 }
1367
1368 // called for each object in the heap
1369 void do_object(oop o);
1370 };
1371
1372 void HeapObjectDumper::do_object(oop o) {
1373 // hide the sentinel for deleted handles
1374 if (o == JNIHandles::deleted_handle()) return;
1375
1376 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records
1377 if (o->klass() == SystemDictionary::Class_klass()) {
1378 if (!java_lang_Class::is_primitive(o)) {
1379 return;
1380 }
1381 }
1382
1383 if (o->is_instance()) {
1384 // create a HPROF_GC_INSTANCE record for each object
1385 DumperSupport::dump_instance(writer(), o);
1386 mark_end_of_record();
1387 } else if (o->is_objArray()) {
1388 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
1389 DumperSupport::dump_object_array(writer(), objArrayOop(o));
1390 mark_end_of_record();
1391 } else if (o->is_typeArray()) {
1392 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
1393 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
1394 mark_end_of_record();
1395 }
1396 }
1397
1398 // The VM operation that performs the heap dump
1399 class VM_HeapDumper : public VM_GC_Operation {
1400 private:
1401 static VM_HeapDumper* _global_dumper;
1402 static DumpWriter* _global_writer;
1403 DumpWriter* _local_writer;
1404 JavaThread* _oome_thread;
1405 Method* _oome_constructor;
1406 bool _gc_before_heap_dump;
1407 GrowableArray<Klass*>* _klass_map;
1408 ThreadStackTrace** _stack_traces;
1409 int _num_threads;
1410
1411 // accessors and setters
1412 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; }
1413 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; }
1414 void set_global_dumper() {
1415 assert(_global_dumper == NULL, "Error");
1416 _global_dumper = this;
1417 }
1418 void set_global_writer() {
1419 assert(_global_writer == NULL, "Error");
1420 _global_writer = _local_writer;
1421 }
1422 void clear_global_dumper() { _global_dumper = NULL; }
1423 void clear_global_writer() { _global_writer = NULL; }
1424
1425 bool skip_operation() const;
1426
1427 // writes a HPROF_LOAD_CLASS record
1428 static void do_load_class(Klass* k);
1429
1430 // writes a HPROF_GC_CLASS_DUMP record for the given class
1431 // (and each array class too)
1432 static void do_class_dump(Klass* k);
1433
1434 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1435 // array (and each multi-dimensional array too)
1436 static void do_basic_type_array_class_dump(Klass* k);
1437
1438 // HPROF_GC_ROOT_THREAD_OBJ records
1439 int do_thread(JavaThread* thread, u4 thread_serial_num);
1440 void do_threads();
1441
1442 void add_class_serial_number(Klass* k, int serial_num) {
1443 _klass_map->at_put_grow(serial_num, k);
1444 }
1445
1446 // HPROF_TRACE and HPROF_FRAME records
1447 void dump_stack_traces();
1448
1449 public:
1450 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) :
1451 VM_GC_Operation(0 /* total collections, dummy, ignored */,
1452 GCCause::_heap_dump /* GC Cause */,
1453 0 /* total full collections, dummy, ignored */,
1454 gc_before_heap_dump) {
1455 _local_writer = writer;
1456 _gc_before_heap_dump = gc_before_heap_dump;
1457 _klass_map = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true);
1458 _stack_traces = NULL;
1459 _num_threads = 0;
1460 if (oome) {
1461 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread");
1462 // get OutOfMemoryError zero-parameter constructor
1463 InstanceKlass* oome_ik = SystemDictionary::OutOfMemoryError_klass();
1464 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(),
1465 vmSymbols::void_method_signature());
1466 // get thread throwing OOME when generating the heap dump at OOME
1467 _oome_thread = JavaThread::current();
1468 } else {
1469 _oome_thread = NULL;
1470 _oome_constructor = NULL;
1471 }
1472 }
1473 ~VM_HeapDumper() {
1474 if (_stack_traces != NULL) {
1475 for (int i=0; i < _num_threads; i++) {
1476 delete _stack_traces[i];
1477 }
1478 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces);
1479 }
1480 delete _klass_map;
1481 }
1482
1483 VMOp_Type type() const { return VMOp_HeapDumper; }
1484 // used to mark sub-record boundary
1485 void check_segment_length();
1486 void doit();
1487 };
1488
1489 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL;
1490 DumpWriter* VM_HeapDumper::_global_writer = NULL;
1491
1492 bool VM_HeapDumper::skip_operation() const {
1493 return false;
1494 }
1495
1496 // writes a HPROF_HEAP_DUMP_SEGMENT record
1497 void DumperSupport::write_dump_header(DumpWriter* writer) {
1498 if (writer->is_open()) {
1499 writer->write_u1(HPROF_HEAP_DUMP_SEGMENT);
1500 writer->write_u4(0); // current ticks
1501
1502 // record the starting position for the dump (its length will be fixed up later)
1503 writer->set_dump_start(writer->current_offset());
1504 writer->write_u4(0);
1505 }
1506 }
1507
1508 // fixes up the length of the current dump record
1509 void DumperSupport::write_current_dump_record_length(DumpWriter* writer) {
1510 if (writer->is_open()) {
1511 julong dump_end = writer->bytes_written() + writer->bytes_unwritten();
1512 julong dump_len = writer->current_record_length();
1513
1514 // record length must fit in a u4
1515 if (dump_len > max_juint) {
1516 warning("record is too large");
1517 }
1518
1519 // seek to the dump start and fix-up the length
1520 assert(writer->dump_start() >= 0, "no dump start recorded");
1521 writer->seek_to_offset(writer->dump_start());
1522 writer->write_u4((u4)dump_len);
1523
1524 // adjust the total size written to keep the bytes written correct.
1525 writer->adjust_bytes_written(-((jlong) sizeof(u4)));
1526
1527 // seek to dump end so we can continue
1528 writer->seek_to_offset(dump_end);
1529
1530 // no current dump record
1531 writer->set_dump_start((jlong)-1);
1532 }
1533 }
1534
1535 // used on a sub-record boundary to check if we need to start a
1536 // new segment.
1537 void VM_HeapDumper::check_segment_length() {
1538 if (writer()->is_open()) {
1539 julong dump_len = writer()->current_record_length();
1540
1541 if (dump_len > 2UL*G) {
1542 DumperSupport::write_current_dump_record_length(writer());
1543 DumperSupport::write_dump_header(writer());
1544 }
1545 }
1546 }
1547
1548 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
1549 void DumperSupport::end_of_dump(DumpWriter* writer) {
1550 if (writer->is_open()) {
1551 write_current_dump_record_length(writer);
1552
1553 writer->write_u1(HPROF_HEAP_DUMP_END);
1554 writer->write_u4(0);
1555 writer->write_u4(0);
1556 }
1557 }
1558
1559 // marks sub-record boundary
1560 void HeapObjectDumper::mark_end_of_record() {
1561 dumper()->check_segment_length();
1562 }
1563
1564 // writes a HPROF_LOAD_CLASS record for the class (and each of its
1565 // array classes)
1566 void VM_HeapDumper::do_load_class(Klass* k) {
1567 static u4 class_serial_num = 0;
1568
1569 // len of HPROF_LOAD_CLASS record
1570 u4 remaining = 2*oopSize + 2*sizeof(u4);
1571
1572 // write a HPROF_LOAD_CLASS for the class and each array class
1573 do {
1574 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
1575
1576 // class serial number is just a number
1577 writer()->write_u4(++class_serial_num);
1578
1579 // class ID
1580 Klass* klass = k;
1581 writer()->write_classID(klass);
1582
1583 // add the Klass* and class serial number pair
1584 dumper()->add_class_serial_number(klass, class_serial_num);
1585
1586 writer()->write_u4(STACK_TRACE_ID);
1587
1588 // class name ID
1589 Symbol* name = klass->name();
1590 writer()->write_symbolID(name);
1591
1592 // write a LOAD_CLASS record for the array type (if it exists)
1593 k = klass->array_klass_or_null();
1594 } while (k != NULL);
1595 }
1596
1597 // writes a HPROF_GC_CLASS_DUMP record for the given class
1598 void VM_HeapDumper::do_class_dump(Klass* k) {
1599 if (k->is_instance_klass()) {
1600 DumperSupport::dump_class_and_array_classes(writer(), k);
1601 }
1602 }
1603
1604 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1605 // array (and each multi-dimensional array too)
1606 void VM_HeapDumper::do_basic_type_array_class_dump(Klass* k) {
1607 DumperSupport::dump_basic_type_array_class(writer(), k);
1608 }
1609
1610 // Walk the stack of the given thread.
1611 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local
1612 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local
1613 //
1614 // It returns the number of Java frames in this thread stack
1615 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) {
1616 JNILocalsDumper blk(writer(), thread_serial_num);
1617
1618 oop threadObj = java_thread->threadObj();
1619 assert(threadObj != NULL, "sanity check");
1620
1621 int stack_depth = 0;
1622 if (java_thread->has_last_Java_frame()) {
1623
1624 // vframes are resource allocated
1625 Thread* current_thread = Thread::current();
1626 ResourceMark rm(current_thread);
1627 HandleMark hm(current_thread);
1628
1629 RegisterMap reg_map(java_thread);
1630 frame f = java_thread->last_frame();
1631 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread);
1632 frame* last_entry_frame = NULL;
1633 int extra_frames = 0;
1634
1635 if (java_thread == _oome_thread && _oome_constructor != NULL) {
1636 extra_frames++;
1637 }
1638 while (vf != NULL) {
1639 blk.set_frame_number(stack_depth);
1640 if (vf->is_java_frame()) {
1641
1642 // java frame (interpreted, compiled, ...)
1643 javaVFrame *jvf = javaVFrame::cast(vf);
1644 if (!(jvf->method()->is_native())) {
1645 StackValueCollection* locals = jvf->locals();
1646 for (int slot=0; slot<locals->size(); slot++) {
1647 if (locals->at(slot)->type() == T_OBJECT) {
1648 oop o = locals->obj_at(slot)();
1649
1650 if (o != NULL) {
1651 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1652 writer()->write_objectID(o);
1653 writer()->write_u4(thread_serial_num);
1654 writer()->write_u4((u4) (stack_depth + extra_frames));
1655 }
1656 }
1657 }
1658 StackValueCollection *exprs = jvf->expressions();
1659 for(int index = 0; index < exprs->size(); index++) {
1660 if (exprs->at(index)->type() == T_OBJECT) {
1661 oop o = exprs->obj_at(index)();
1662 if (o != NULL) {
1663 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1664 writer()->write_objectID(o);
1665 writer()->write_u4(thread_serial_num);
1666 writer()->write_u4((u4) (stack_depth + extra_frames));
1667 }
1668 }
1669 }
1670 } else {
1671 // native frame
1672 if (stack_depth == 0) {
1673 // JNI locals for the top frame.
1674 java_thread->active_handles()->oops_do(&blk);
1675 } else {
1676 if (last_entry_frame != NULL) {
1677 // JNI locals for the entry frame
1678 assert(last_entry_frame->is_entry_frame(), "checking");
1679 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk);
1680 }
1681 }
1682 }
1683 // increment only for Java frames
1684 stack_depth++;
1685 last_entry_frame = NULL;
1686
1687 } else {
1688 // externalVFrame - if it's an entry frame then report any JNI locals
1689 // as roots when we find the corresponding native javaVFrame
1690 frame* fr = vf->frame_pointer();
1691 assert(fr != NULL, "sanity check");
1692 if (fr->is_entry_frame()) {
1693 last_entry_frame = fr;
1694 }
1695 }
1696 vf = vf->sender();
1697 }
1698 } else {
1699 // no last java frame but there may be JNI locals
1700 java_thread->active_handles()->oops_do(&blk);
1701 }
1702 return stack_depth;
1703 }
1704
1705
1706 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk
1707 // the stack so that locals and JNI locals are dumped.
1708 void VM_HeapDumper::do_threads() {
1709 for (int i=0; i < _num_threads; i++) {
1710 JavaThread* thread = _stack_traces[i]->thread();
1711 oop threadObj = thread->threadObj();
1712 u4 thread_serial_num = i+1;
1713 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID;
1714 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ);
1715 writer()->write_objectID(threadObj);
1716 writer()->write_u4(thread_serial_num); // thread number
1717 writer()->write_u4(stack_serial_num); // stack trace serial number
1718 int num_frames = do_thread(thread, thread_serial_num);
1719 assert(num_frames == _stack_traces[i]->get_stack_depth(),
1720 "total number of Java frames not matched");
1721 }
1722 }
1723
1724
1725 // The VM operation that dumps the heap. The dump consists of the following
1726 // records:
1727 //
1728 // HPROF_HEADER
1729 // [HPROF_UTF8]*
1730 // [HPROF_LOAD_CLASS]*
1731 // [[HPROF_FRAME]*|HPROF_TRACE]*
1732 // [HPROF_GC_CLASS_DUMP]*
1733 // [HPROF_HEAP_DUMP_SEGMENT]*
1734 // HPROF_HEAP_DUMP_END
1735 //
1736 // The HPROF_TRACE records represent the stack traces where the heap dump
1737 // is generated and a "dummy trace" record which does not include
1738 // any frames. The dummy trace record is used to be referenced as the
1739 // unknown object alloc site.
1740 //
1741 // Each HPROF_HEAP_DUMP_SEGMENT record has a length followed by sub-records.
1742 // To allow the heap dump be generated in a single pass we remember the position
1743 // of the dump length and fix it up after all sub-records have been written.
1744 // To generate the sub-records we iterate over the heap, writing
1745 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP
1746 // records as we go. Once that is done we write records for some of the GC
1747 // roots.
1748
1749 void VM_HeapDumper::doit() {
1750
1751 HandleMark hm;
1752 CollectedHeap* ch = GC::gc()->heap();
1753
1754 ch->ensure_parsability(false); // must happen, even if collection does
1755 // not happen (e.g. due to GCLocker)
1756
1757 if (_gc_before_heap_dump) {
1758 if (GCLocker::is_active()) {
1759 warning("GC locker is held; pre-heapdump GC was skipped");
1760 } else {
1761 ch->collect_as_vm_thread(GCCause::_heap_dump);
1762 }
1763 }
1764
1765 // At this point we should be the only dumper active, so
1766 // the following should be safe.
1767 set_global_dumper();
1768 set_global_writer();
1769
1770 // Write the file header - we always use 1.0.2
1771 size_t used = ch->used();
1772 const char* header = "JAVA PROFILE 1.0.2";
1773
1774 // header is few bytes long - no chance to overflow int
1775 writer()->write_raw((void*)header, (int)strlen(header));
1776 writer()->write_u1(0); // terminator
1777 writer()->write_u4(oopSize);
1778 writer()->write_u8(os::javaTimeMillis());
1779
1780 // HPROF_UTF8 records
1781 SymbolTableDumper sym_dumper(writer());
1782 SymbolTable::symbols_do(&sym_dumper);
1783
1784 // write HPROF_LOAD_CLASS records
1785 ClassLoaderDataGraph::classes_do(&do_load_class);
1786 Universe::basic_type_classes_do(&do_load_class);
1787
1788 // write HPROF_FRAME and HPROF_TRACE records
1789 // this must be called after _klass_map is built when iterating the classes above.
1790 dump_stack_traces();
1791
1792 // write HPROF_HEAP_DUMP_SEGMENT
1793 DumperSupport::write_dump_header(writer());
1794
1795 // Writes HPROF_GC_CLASS_DUMP records
1796 ClassLoaderDataGraph::classes_do(&do_class_dump);
1797 Universe::basic_type_classes_do(&do_basic_type_array_class_dump);
1798 check_segment_length();
1799
1800 // writes HPROF_GC_INSTANCE_DUMP records.
1801 // After each sub-record is written check_segment_length will be invoked
1802 // to check if the current segment exceeds a threshold. If so, a new
1803 // segment is started.
1804 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk
1805 // of the heap dump.
1806 HeapObjectDumper obj_dumper(this, writer());
1807 GC::gc()->heap()->safe_object_iterate(&obj_dumper);
1808
1809 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
1810 do_threads();
1811 check_segment_length();
1812
1813 // HPROF_GC_ROOT_MONITOR_USED
1814 MonitorUsedDumper mon_dumper(writer());
1815 ObjectSynchronizer::oops_do(&mon_dumper);
1816 check_segment_length();
1817
1818 // HPROF_GC_ROOT_JNI_GLOBAL
1819 JNIGlobalsDumper jni_dumper(writer());
1820 JNIHandles::oops_do(&jni_dumper);
1821 check_segment_length();
1822
1823 // HPROF_GC_ROOT_STICKY_CLASS
1824 StickyClassDumper class_dumper(writer());
1825 SystemDictionary::always_strong_classes_do(&class_dumper);
1826
1827 // fixes up the length of the dump record and writes the HPROF_HEAP_DUMP_END record.
1828 DumperSupport::end_of_dump(writer());
1829
1830 // Now we clear the global variables, so that a future dumper might run.
1831 clear_global_dumper();
1832 clear_global_writer();
1833 }
1834
1835 void VM_HeapDumper::dump_stack_traces() {
1836 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites
1837 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4));
1838 writer()->write_u4((u4) STACK_TRACE_ID);
1839 writer()->write_u4(0); // thread number
1840 writer()->write_u4(0); // frame count
1841
1842 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal);
1843 int frame_serial_num = 0;
1844 for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) {
1845 oop threadObj = thread->threadObj();
1846 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) {
1847 // dump thread stack trace
1848 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false);
1849 stack_trace->dump_stack_at_safepoint(-1);
1850 _stack_traces[_num_threads++] = stack_trace;
1851
1852 // write HPROF_FRAME records for this thread's stack trace
1853 int depth = stack_trace->get_stack_depth();
1854 int thread_frame_start = frame_serial_num;
1855 int extra_frames = 0;
1856 // write fake frame that makes it look like the thread, which caused OOME,
1857 // is in the OutOfMemoryError zero-parameter constructor
1858 if (thread == _oome_thread && _oome_constructor != NULL) {
1859 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder());
1860 // the class serial number starts from 1
1861 assert(oome_serial_num > 0, "OutOfMemoryError class not found");
1862 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num,
1863 _oome_constructor, 0);
1864 extra_frames++;
1865 }
1866 for (int j=0; j < depth; j++) {
1867 StackFrameInfo* frame = stack_trace->stack_frame_at(j);
1868 Method* m = frame->method();
1869 int class_serial_num = _klass_map->find(m->method_holder());
1870 // the class serial number starts from 1
1871 assert(class_serial_num > 0, "class not found");
1872 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci());
1873 }
1874 depth += extra_frames;
1875
1876 // write HPROF_TRACE record for one thread
1877 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize);
1878 int stack_serial_num = _num_threads + STACK_TRACE_ID;
1879 writer()->write_u4(stack_serial_num); // stack trace serial number
1880 writer()->write_u4((u4) _num_threads); // thread serial number
1881 writer()->write_u4(depth); // frame count
1882 for (int j=1; j <= depth; j++) {
1883 writer()->write_id(thread_frame_start + j);
1884 }
1885 }
1886 }
1887 }
1888
1889 // dump the heap to given path.
1890 int HeapDumper::dump(const char* path) {
1891 assert(path != NULL && strlen(path) > 0, "path missing");
1892
1893 // print message in interactive case
1894 if (print_to_tty()) {
1895 tty->print_cr("Dumping heap to %s ...", path);
1896 timer()->start();
1897 }
1898
1899 // create the dump writer. If the file can be opened then bail
1900 DumpWriter writer(path);
1901 if (!writer.is_open()) {
1902 set_error(writer.error());
1903 if (print_to_tty()) {
1904 tty->print_cr("Unable to create %s: %s", path,
1905 (error() != NULL) ? error() : "reason unknown");
1906 }
1907 return -1;
1908 }
1909
1910 // generate the dump
1911 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome);
1912 if (Thread::current()->is_VM_thread()) {
1913 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint");
1914 dumper.doit();
1915 } else {
1916 VMThread::execute(&dumper);
1917 }
1918
1919 // close dump file and record any error that the writer may have encountered
1920 writer.close();
1921 set_error(writer.error());
1922
1923 // print message in interactive case
1924 if (print_to_tty()) {
1925 timer()->stop();
1926 if (error() == NULL) {
1927 tty->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]",
1928 writer.bytes_written(), timer()->seconds());
1929 } else {
1930 tty->print_cr("Dump file is incomplete: %s", writer.error());
1931 }
1932 }
1933
1934 return (writer.error() == NULL) ? 0 : -1;
1935 }
1936
1937 // stop timer (if still active), and free any error string we might be holding
1938 HeapDumper::~HeapDumper() {
1939 if (timer()->is_active()) {
1940 timer()->stop();
1941 }
1942 set_error(NULL);
1943 }
1944
1945
1946 // returns the error string (resource allocated), or NULL
1947 char* HeapDumper::error_as_C_string() const {
1948 if (error() != NULL) {
1949 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1);
1950 strcpy(str, error());
1951 return str;
1952 } else {
1953 return NULL;
1954 }
1955 }
1956
1957 // set the error string
1958 void HeapDumper::set_error(char* error) {
1959 if (_error != NULL) {
1960 os::free(_error);
1961 }
1962 if (error == NULL) {
1963 _error = NULL;
1964 } else {
1965 _error = os::strdup(error);
1966 assert(_error != NULL, "allocation failure");
1967 }
1968 }
1969
1970 // Called by out-of-memory error reporting by a single Java thread
1971 // outside of a JVM safepoint
1972 void HeapDumper::dump_heap_from_oome() {
1973 HeapDumper::dump_heap(true);
1974 }
1975
1976 // Called by error reporting by a single Java thread outside of a JVM safepoint,
1977 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various
1978 // callers are strictly serialized and guaranteed not to interfere below. For more
1979 // general use, however, this method will need modification to prevent
1980 // inteference when updating the static variables base_path and dump_file_seq below.
1981 void HeapDumper::dump_heap() {
1982 HeapDumper::dump_heap(false);
1983 }
1984
1985 void HeapDumper::dump_heap(bool oome) {
1986 static char base_path[JVM_MAXPATHLEN] = {'\0'};
1987 static uint dump_file_seq = 0;
1988 char* my_path;
1989 const int max_digit_chars = 20;
1990
1991 const char* dump_file_name = "java_pid";
1992 const char* dump_file_ext = ".hprof";
1993
1994 // The dump file defaults to java_pid<pid>.hprof in the current working
1995 // directory. HeapDumpPath=<file> can be used to specify an alternative
1996 // dump file name or a directory where dump file is created.
1997 if (dump_file_seq == 0) { // first time in, we initialize base_path
1998 // Calculate potentially longest base path and check if we have enough
1999 // allocated statically.
2000 const size_t total_length =
2001 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) +
2002 strlen(os::file_separator()) + max_digit_chars +
2003 strlen(dump_file_name) + strlen(dump_file_ext) + 1;
2004 if (total_length > sizeof(base_path)) {
2005 warning("Cannot create heap dump file. HeapDumpPath is too long.");
2006 return;
2007 }
2008
2009 bool use_default_filename = true;
2010 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') {
2011 // HeapDumpPath=<file> not specified
2012 } else {
2013 strcpy(base_path, HeapDumpPath);
2014 // check if the path is a directory (must exist)
2015 DIR* dir = os::opendir(base_path);
2016 if (dir == NULL) {
2017 use_default_filename = false;
2018 } else {
2019 // HeapDumpPath specified a directory. We append a file separator
2020 // (if needed).
2021 os::closedir(dir);
2022 size_t fs_len = strlen(os::file_separator());
2023 if (strlen(base_path) >= fs_len) {
2024 char* end = base_path;
2025 end += (strlen(base_path) - fs_len);
2026 if (strcmp(end, os::file_separator()) != 0) {
2027 strcat(base_path, os::file_separator());
2028 }
2029 }
2030 }
2031 }
2032 // If HeapDumpPath wasn't a file name then we append the default name
2033 if (use_default_filename) {
2034 const size_t dlen = strlen(base_path); // if heap dump dir specified
2035 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s",
2036 dump_file_name, os::current_process_id(), dump_file_ext);
2037 }
2038 const size_t len = strlen(base_path) + 1;
2039 my_path = (char*)os::malloc(len, mtInternal);
2040 if (my_path == NULL) {
2041 warning("Cannot create heap dump file. Out of system memory.");
2042 return;
2043 }
2044 strncpy(my_path, base_path, len);
2045 } else {
2046 // Append a sequence number id for dumps following the first
2047 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0
2048 my_path = (char*)os::malloc(len, mtInternal);
2049 if (my_path == NULL) {
2050 warning("Cannot create heap dump file. Out of system memory.");
2051 return;
2052 }
2053 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq);
2054 }
2055 dump_file_seq++; // increment seq number for next time we dump
2056
2057 HeapDumper dumper(false /* no GC before heap dump */,
2058 true /* send to tty */,
2059 oome /* pass along out-of-memory-error flag */);
2060 dumper.dump(my_path);
2061 os::free(my_path);
2062 }