1 /*
2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "classfile/symbolTable.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "gc/shared/gcLocker.inline.hpp"
31 #include "gc/shared/genCollectedHeap.hpp"
32 #include "gc/shared/vmGCOperations.hpp"
33 #include "memory/allocation.inline.hpp"
34 #include "memory/resourceArea.hpp"
35 #include "memory/universe.hpp"
36 #include "oops/objArrayKlass.hpp"
37 #include "oops/objArrayOop.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "oops/typeArrayOop.inline.hpp"
40 #include "runtime/handles.inline.hpp"
41 #include "runtime/javaCalls.hpp"
42 #include "runtime/jniHandles.hpp"
43 #include "runtime/os.hpp"
44 #include "runtime/reflectionUtils.hpp"
45 #include "runtime/thread.inline.hpp"
46 #include "runtime/threadSMR.hpp"
47 #include "runtime/vframe.hpp"
48 #include "runtime/vmThread.hpp"
49 #include "runtime/vm_operations.hpp"
50 #include "services/heapDumper.hpp"
51 #include "services/threadService.hpp"
52 #include "utilities/macros.hpp"
53 #include "utilities/ostream.hpp"
54 #if INCLUDE_ALL_GCS
55 #include "gc/parallel/parallelScavengeHeap.hpp"
56 #endif // INCLUDE_ALL_GCS
57
58 /*
59 * HPROF binary format - description copied from:
60 * src/share/demo/jvmti/hprof/hprof_io.c
61 *
62 *
63 * header "JAVA PROFILE 1.0.2" (0-terminated)
64 *
65 * u4 size of identifiers. Identifiers are used to represent
66 * UTF8 strings, objects, stack traces, etc. They usually
67 * have the same size as host pointers. For example, on
68 * Solaris and Win32, the size is 4.
69 * u4 high word
70 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70
71 * [record]* a sequence of records.
72 *
73 *
74 * Record format:
75 *
76 * u1 a TAG denoting the type of the record
77 * u4 number of *microseconds* since the time stamp in the
78 * header. (wraps around in a little more than an hour)
79 * u4 number of bytes *remaining* in the record. Note that
80 * this number excludes the tag and the length field itself.
81 * [u1]* BODY of the record (a sequence of bytes)
82 *
83 *
84 * The following TAGs are supported:
85 *
86 * TAG BODY notes
87 *----------------------------------------------------------
88 * HPROF_UTF8 a UTF8-encoded name
89 *
90 * id name ID
91 * [u1]* UTF8 characters (no trailing zero)
92 *
93 * HPROF_LOAD_CLASS a newly loaded class
94 *
95 * u4 class serial number (> 0)
96 * id class object ID
97 * u4 stack trace serial number
98 * id class name ID
99 *
100 * HPROF_UNLOAD_CLASS an unloading class
101 *
102 * u4 class serial_number
103 *
104 * HPROF_FRAME a Java stack frame
105 *
106 * id stack frame ID
107 * id method name ID
108 * id method signature ID
109 * id source file name ID
110 * u4 class serial number
111 * i4 line number. >0: normal
112 * -1: unknown
113 * -2: compiled method
114 * -3: native method
115 *
116 * HPROF_TRACE a Java stack trace
117 *
118 * u4 stack trace serial number
119 * u4 thread serial number
120 * u4 number of frames
121 * [id]* stack frame IDs
122 *
123 *
124 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC
125 *
126 * u2 flags 0x0001: incremental vs. complete
127 * 0x0002: sorted by allocation vs. live
128 * 0x0004: whether to force a GC
129 * u4 cutoff ratio
130 * u4 total live bytes
131 * u4 total live instances
132 * u8 total bytes allocated
133 * u8 total instances allocated
134 * u4 number of sites that follow
135 * [u1 is_array: 0: normal object
136 * 2: object array
137 * 4: boolean array
138 * 5: char array
139 * 6: float array
140 * 7: double array
141 * 8: byte array
142 * 9: short array
143 * 10: int array
144 * 11: long array
145 * u4 class serial number (may be zero during startup)
146 * u4 stack trace serial number
147 * u4 number of bytes alive
148 * u4 number of instances alive
149 * u4 number of bytes allocated
150 * u4]* number of instance allocated
151 *
152 * HPROF_START_THREAD a newly started thread.
153 *
154 * u4 thread serial number (> 0)
155 * id thread object ID
156 * u4 stack trace serial number
157 * id thread name ID
158 * id thread group name ID
159 * id thread group parent name ID
160 *
161 * HPROF_END_THREAD a terminating thread.
162 *
163 * u4 thread serial number
164 *
165 * HPROF_HEAP_SUMMARY heap summary
166 *
167 * u4 total live bytes
168 * u4 total live instances
169 * u8 total bytes allocated
170 * u8 total instances allocated
171 *
172 * HPROF_HEAP_DUMP denote a heap dump
173 *
174 * [heap dump sub-records]*
175 *
176 * There are four kinds of heap dump sub-records:
177 *
178 * u1 sub-record type
179 *
180 * HPROF_GC_ROOT_UNKNOWN unknown root
181 *
182 * id object ID
183 *
184 * HPROF_GC_ROOT_THREAD_OBJ thread object
185 *
186 * id thread object ID (may be 0 for a
187 * thread newly attached through JNI)
188 * u4 thread sequence number
189 * u4 stack trace sequence number
190 *
191 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root
192 *
193 * id object ID
194 * id JNI global ref ID
195 *
196 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref
197 *
198 * id object ID
199 * u4 thread serial number
200 * u4 frame # in stack trace (-1 for empty)
201 *
202 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame
203 *
204 * id object ID
205 * u4 thread serial number
206 * u4 frame # in stack trace (-1 for empty)
207 *
208 * HPROF_GC_ROOT_NATIVE_STACK Native stack
209 *
210 * id object ID
211 * u4 thread serial number
212 *
213 * HPROF_GC_ROOT_STICKY_CLASS System class
214 *
215 * id object ID
216 *
217 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block
218 *
219 * id object ID
220 * u4 thread serial number
221 *
222 * HPROF_GC_ROOT_MONITOR_USED Busy monitor
223 *
224 * id object ID
225 *
226 * HPROF_GC_CLASS_DUMP dump of a class object
227 *
228 * id class object ID
229 * u4 stack trace serial number
230 * id super class object ID
231 * id class loader object ID
232 * id signers object ID
233 * id protection domain object ID
234 * id reserved
235 * id reserved
236 *
237 * u4 instance size (in bytes)
238 *
239 * u2 size of constant pool
240 * [u2, constant pool index,
241 * ty, type
242 * 2: object
243 * 4: boolean
244 * 5: char
245 * 6: float
246 * 7: double
247 * 8: byte
248 * 9: short
249 * 10: int
250 * 11: long
251 * vl]* and value
252 *
253 * u2 number of static fields
254 * [id, static field name,
255 * ty, type,
256 * vl]* and value
257 *
258 * u2 number of inst. fields (not inc. super)
259 * [id, instance field name,
260 * ty]* type
261 *
262 * HPROF_GC_INSTANCE_DUMP dump of a normal object
263 *
264 * id object ID
265 * u4 stack trace serial number
266 * id class object ID
267 * u4 number of bytes that follow
268 * [vl]* instance field values (class, followed
269 * by super, super's super ...)
270 *
271 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array
272 *
273 * id array object ID
274 * u4 stack trace serial number
275 * u4 number of elements
276 * id array class ID
277 * [id]* elements
278 *
279 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array
280 *
281 * id array object ID
282 * u4 stack trace serial number
283 * u4 number of elements
284 * u1 element type
285 * 4: boolean array
286 * 5: char array
287 * 6: float array
288 * 7: double array
289 * 8: byte array
290 * 9: short array
291 * 10: int array
292 * 11: long array
293 * [u1]* elements
294 *
295 * HPROF_CPU_SAMPLES a set of sample traces of running threads
296 *
297 * u4 total number of samples
298 * u4 # of traces
299 * [u4 # of samples
300 * u4]* stack trace serial number
301 *
302 * HPROF_CONTROL_SETTINGS the settings of on/off switches
303 *
304 * u4 0x00000001: alloc traces on/off
305 * 0x00000002: cpu sampling on/off
306 * u2 stack trace depth
307 *
308 *
309 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
310 * be generated as a sequence of heap dump segments. This sequence is
311 * terminated by an end record. The additional tags allowed by format
312 * "JAVA PROFILE 1.0.2" are:
313 *
314 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
315 *
316 * [heap dump sub-records]*
317 * The same sub-record types allowed by HPROF_HEAP_DUMP
318 *
319 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
320 *
321 */
322
323
324 // HPROF tags
325
326 typedef enum {
327 // top-level records
328 HPROF_UTF8 = 0x01,
329 HPROF_LOAD_CLASS = 0x02,
330 HPROF_UNLOAD_CLASS = 0x03,
331 HPROF_FRAME = 0x04,
332 HPROF_TRACE = 0x05,
333 HPROF_ALLOC_SITES = 0x06,
334 HPROF_HEAP_SUMMARY = 0x07,
335 HPROF_START_THREAD = 0x0A,
336 HPROF_END_THREAD = 0x0B,
337 HPROF_HEAP_DUMP = 0x0C,
338 HPROF_CPU_SAMPLES = 0x0D,
339 HPROF_CONTROL_SETTINGS = 0x0E,
340
341 // 1.0.2 record types
342 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
343 HPROF_HEAP_DUMP_END = 0x2C,
344
345 // field types
346 HPROF_ARRAY_OBJECT = 0x01,
347 HPROF_NORMAL_OBJECT = 0x02,
348 HPROF_BOOLEAN = 0x04,
349 HPROF_CHAR = 0x05,
350 HPROF_FLOAT = 0x06,
351 HPROF_DOUBLE = 0x07,
352 HPROF_BYTE = 0x08,
353 HPROF_SHORT = 0x09,
354 HPROF_INT = 0x0A,
355 HPROF_LONG = 0x0B,
356
357 // data-dump sub-records
358 HPROF_GC_ROOT_UNKNOWN = 0xFF,
359 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
360 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
361 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
362 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
363 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
364 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
365 HPROF_GC_ROOT_MONITOR_USED = 0x07,
366 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
367 HPROF_GC_CLASS_DUMP = 0x20,
368 HPROF_GC_INSTANCE_DUMP = 0x21,
369 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
370 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
371 } hprofTag;
372
373 // Default stack trace ID (used for dummy HPROF_TRACE record)
374 enum {
375 STACK_TRACE_ID = 1,
376 INITIAL_CLASS_COUNT = 200
377 };
378
379 // Supports I/O operations on a dump file
380
381 class DumpWriter : public StackObj {
382 private:
383 enum {
384 io_buffer_size = 8*M
385 };
386
387 int _fd; // file descriptor (-1 if dump file not open)
388 julong _bytes_written; // number of byte written to dump file
389
390 char* _buffer; // internal buffer
391 size_t _size;
392 size_t _pos;
393
394 jlong _dump_start;
395
396 char* _error; // error message when I/O fails
397
398 void set_file_descriptor(int fd) { _fd = fd; }
399 int file_descriptor() const { return _fd; }
400
401 char* buffer() const { return _buffer; }
402 size_t buffer_size() const { return _size; }
403 size_t position() const { return _pos; }
404 void set_position(size_t pos) { _pos = pos; }
405
406 void set_error(const char* error) { _error = (char*)os::strdup(error); }
407
408 // all I/O go through this function
409 void write_internal(void* s, size_t len);
410
411 public:
412 DumpWriter(const char* path);
413 ~DumpWriter();
414
415 void close();
416 bool is_open() const { return file_descriptor() >= 0; }
417 void flush();
418
419 jlong dump_start() const { return _dump_start; }
420 void set_dump_start(jlong pos);
421 julong current_record_length();
422
423 // total number of bytes written to the disk
424 julong bytes_written() const { return _bytes_written; }
425
426 // adjust the number of bytes written to disk (used to keep the count
427 // of the number of bytes written in case of rewrites)
428 void adjust_bytes_written(jlong n) { _bytes_written += n; }
429
430 // number of (buffered) bytes as yet unwritten to the dump file
431 size_t bytes_unwritten() const { return position(); }
432
433 char* error() const { return _error; }
434
435 jlong current_offset();
436 void seek_to_offset(jlong pos);
437
438 // writer functions
439 void write_raw(void* s, size_t len);
440 void write_u1(u1 x) { write_raw((void*)&x, 1); }
441 void write_u2(u2 x);
442 void write_u4(u4 x);
443 void write_u8(u8 x);
444 void write_objectID(oop o);
445 void write_symbolID(Symbol* o);
446 void write_classID(Klass* k);
447 void write_id(u4 x);
448 };
449
450 DumpWriter::DumpWriter(const char* path) {
451 // try to allocate an I/O buffer of io_buffer_size. If there isn't
452 // sufficient memory then reduce size until we can allocate something.
453 _size = io_buffer_size;
454 do {
455 _buffer = (char*)os::malloc(_size, mtInternal);
456 if (_buffer == NULL) {
457 _size = _size >> 1;
458 }
459 } while (_buffer == NULL && _size > 0);
460 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check");
461 _pos = 0;
462 _error = NULL;
463 _bytes_written = 0L;
464 _dump_start = (jlong)-1;
465 _fd = os::create_binary_file(path, false); // don't replace existing file
466
467 // if the open failed we record the error
468 if (_fd < 0) {
469 _error = (char*)os::strdup(os::strerror(errno));
470 }
471 }
472
473 DumpWriter::~DumpWriter() {
474 // flush and close dump file
475 if (is_open()) {
476 close();
477 }
478 if (_buffer != NULL) os::free(_buffer);
479 if (_error != NULL) os::free(_error);
480 }
481
482 // closes dump file (if open)
483 void DumpWriter::close() {
484 // flush and close dump file
485 if (is_open()) {
486 flush();
487 os::close(file_descriptor());
488 set_file_descriptor(-1);
489 }
490 }
491
492 // sets the dump starting position
493 void DumpWriter::set_dump_start(jlong pos) {
494 _dump_start = pos;
495 }
496
497 julong DumpWriter::current_record_length() {
498 if (is_open()) {
499 // calculate the size of the dump record
500 julong dump_end = bytes_written() + bytes_unwritten();
501 assert(dump_end == (size_t)current_offset(), "checking");
502 julong dump_len = dump_end - dump_start() - 4;
503 return dump_len;
504 }
505 return 0;
506 }
507
508 // write directly to the file
509 void DumpWriter::write_internal(void* s, size_t len) {
510 if (is_open()) {
511 const char* pos = (char*)s;
512 ssize_t n = 0;
513 while (len > 0) {
514 uint tmp = (uint)MIN2(len, (size_t)UINT_MAX);
515 n = os::write(file_descriptor(), pos, tmp);
516
517 if (n < 0) {
518 // EINTR cannot happen here, os::write will take care of that
519 set_error(os::strerror(errno));
520 os::close(file_descriptor());
521 set_file_descriptor(-1);
522 return;
523 }
524
525 _bytes_written += n;
526 pos += n;
527 len -= n;
528 }
529 }
530 }
531
532 // write raw bytes
533 void DumpWriter::write_raw(void* s, size_t len) {
534 if (is_open()) {
535 // flush buffer to make room
536 if ((position() + len) >= buffer_size()) {
537 flush();
538 }
539
540 // buffer not available or too big to buffer it
541 if ((buffer() == NULL) || (len >= buffer_size())) {
542 write_internal(s, len);
543 } else {
544 // Should optimize this for u1/u2/u4/u8 sizes.
545 memcpy(buffer() + position(), s, len);
546 set_position(position() + len);
547 }
548 }
549 }
550
551 // flush any buffered bytes to the file
552 void DumpWriter::flush() {
553 if (is_open() && position() > 0) {
554 write_internal(buffer(), position());
555 set_position(0);
556 }
557 }
558
559 jlong DumpWriter::current_offset() {
560 if (is_open()) {
561 // the offset is the file offset plus whatever we have buffered
562 jlong offset = os::current_file_offset(file_descriptor());
563 assert(offset >= 0, "lseek failed");
564 return offset + position();
565 } else {
566 return (jlong)-1;
567 }
568 }
569
570 void DumpWriter::seek_to_offset(jlong off) {
571 assert(off >= 0, "bad offset");
572
573 // need to flush before seeking
574 flush();
575
576 // may be closed due to I/O error
577 if (is_open()) {
578 jlong n = os::seek_to_file_offset(file_descriptor(), off);
579 assert(n >= 0, "lseek failed");
580 }
581 }
582
583 void DumpWriter::write_u2(u2 x) {
584 u2 v;
585 Bytes::put_Java_u2((address)&v, x);
586 write_raw((void*)&v, 2);
587 }
588
589 void DumpWriter::write_u4(u4 x) {
590 u4 v;
591 Bytes::put_Java_u4((address)&v, x);
592 write_raw((void*)&v, 4);
593 }
594
595 void DumpWriter::write_u8(u8 x) {
596 u8 v;
597 Bytes::put_Java_u8((address)&v, x);
598 write_raw((void*)&v, 8);
599 }
600
601 void DumpWriter::write_objectID(oop o) {
602 address a = (address)o;
603 #ifdef _LP64
604 write_u8((u8)a);
605 #else
606 write_u4((u4)a);
607 #endif
608 }
609
610 void DumpWriter::write_symbolID(Symbol* s) {
611 address a = (address)((uintptr_t)s);
612 #ifdef _LP64
613 write_u8((u8)a);
614 #else
615 write_u4((u4)a);
616 #endif
617 }
618
619 void DumpWriter::write_id(u4 x) {
620 #ifdef _LP64
621 write_u8((u8) x);
622 #else
623 write_u4(x);
624 #endif
625 }
626
627 // We use java mirror as the class ID
628 void DumpWriter::write_classID(Klass* k) {
629 write_objectID(k->java_mirror());
630 }
631
632
633
634 // Support class with a collection of functions used when dumping the heap
635
636 class DumperSupport : AllStatic {
637 public:
638
639 // write a header of the given type
640 static void write_header(DumpWriter* writer, hprofTag tag, u4 len);
641
642 // returns hprof tag for the given type signature
643 static hprofTag sig2tag(Symbol* sig);
644 // returns hprof tag for the given basic type
645 static hprofTag type2tag(BasicType type);
646
647 // returns the size of the instance of the given class
648 static u4 instance_size(Klass* k);
649
650 // dump a jfloat
651 static void dump_float(DumpWriter* writer, jfloat f);
652 // dump a jdouble
653 static void dump_double(DumpWriter* writer, jdouble d);
654 // dumps the raw value of the given field
655 static void dump_field_value(DumpWriter* writer, char type, oop obj, int offset);
656 // dumps static fields of the given class
657 static void dump_static_fields(DumpWriter* writer, Klass* k);
658 // dump the raw values of the instance fields of the given object
659 static void dump_instance_fields(DumpWriter* writer, oop o);
660 // dumps the definition of the instance fields for a given class
661 static void dump_instance_field_descriptors(DumpWriter* writer, Klass* k);
662 // creates HPROF_GC_INSTANCE_DUMP record for the given object
663 static void dump_instance(DumpWriter* writer, oop o);
664 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its
665 // array classes
666 static void dump_class_and_array_classes(DumpWriter* writer, Klass* k);
667 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
668 // class (and each multi-dimensional array class too)
669 static void dump_basic_type_array_class(DumpWriter* writer, Klass* k);
670
671 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
672 static void dump_object_array(DumpWriter* writer, objArrayOop array);
673 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
674 static void dump_prim_array(DumpWriter* writer, typeArrayOop array);
675 // create HPROF_FRAME record for the given method and bci
676 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
677
678 // check if we need to truncate an array
679 static int calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size);
680
681 // writes a HPROF_HEAP_DUMP_SEGMENT record
682 static void write_dump_header(DumpWriter* writer);
683
684 // fixes up the length of the current dump record
685 static void write_current_dump_record_length(DumpWriter* writer);
686
687 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
688 static void end_of_dump(DumpWriter* writer);
689 };
690
691 // write a header of the given type
692 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) {
693 writer->write_u1((u1)tag);
694 writer->write_u4(0); // current ticks
695 writer->write_u4(len);
696 }
697
698 // returns hprof tag for the given type signature
699 hprofTag DumperSupport::sig2tag(Symbol* sig) {
700 switch (sig->byte_at(0)) {
701 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT;
702 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT;
703 case JVM_SIGNATURE_BYTE : return HPROF_BYTE;
704 case JVM_SIGNATURE_CHAR : return HPROF_CHAR;
705 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT;
706 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE;
707 case JVM_SIGNATURE_INT : return HPROF_INT;
708 case JVM_SIGNATURE_LONG : return HPROF_LONG;
709 case JVM_SIGNATURE_SHORT : return HPROF_SHORT;
710 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN;
711 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
712 }
713 }
714
715 hprofTag DumperSupport::type2tag(BasicType type) {
716 switch (type) {
717 case T_BYTE : return HPROF_BYTE;
718 case T_CHAR : return HPROF_CHAR;
719 case T_FLOAT : return HPROF_FLOAT;
720 case T_DOUBLE : return HPROF_DOUBLE;
721 case T_INT : return HPROF_INT;
722 case T_LONG : return HPROF_LONG;
723 case T_SHORT : return HPROF_SHORT;
724 case T_BOOLEAN : return HPROF_BOOLEAN;
725 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
726 }
727 }
728
729 // dump a jfloat
730 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) {
731 if (g_isnan(f)) {
732 writer->write_u4(0x7fc00000); // collapsing NaNs
733 } else {
734 union {
735 int i;
736 float f;
737 } u;
738 u.f = (float)f;
739 writer->write_u4((u4)u.i);
740 }
741 }
742
743 // dump a jdouble
744 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) {
745 union {
746 jlong l;
747 double d;
748 } u;
749 if (g_isnan(d)) { // collapsing NaNs
750 u.l = (jlong)(0x7ff80000);
751 u.l = (u.l << 32);
752 } else {
753 u.d = (double)d;
754 }
755 writer->write_u8((u8)u.l);
756 }
757
758 // dumps the raw value of the given field
759 void DumperSupport::dump_field_value(DumpWriter* writer, char type, oop obj, int offset) {
760 switch (type) {
761 case JVM_SIGNATURE_CLASS :
762 case JVM_SIGNATURE_ARRAY : {
763 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF>(offset);
764 assert(oopDesc::is_oop_or_null(o), "Expected an oop or NULL at " PTR_FORMAT, p2i(o));
765 writer->write_objectID(o);
766 break;
767 }
768 case JVM_SIGNATURE_BYTE : {
769 jbyte b = obj->byte_field(offset);
770 writer->write_u1((u1)b);
771 break;
772 }
773 case JVM_SIGNATURE_CHAR : {
774 jchar c = obj->char_field(offset);
775 writer->write_u2((u2)c);
776 break;
777 }
778 case JVM_SIGNATURE_SHORT : {
779 jshort s = obj->short_field(offset);
780 writer->write_u2((u2)s);
781 break;
782 }
783 case JVM_SIGNATURE_FLOAT : {
784 jfloat f = obj->float_field(offset);
785 dump_float(writer, f);
786 break;
787 }
788 case JVM_SIGNATURE_DOUBLE : {
789 jdouble d = obj->double_field(offset);
790 dump_double(writer, d);
791 break;
792 }
793 case JVM_SIGNATURE_INT : {
794 jint i = obj->int_field(offset);
795 writer->write_u4((u4)i);
796 break;
797 }
798 case JVM_SIGNATURE_LONG : {
799 jlong l = obj->long_field(offset);
800 writer->write_u8((u8)l);
801 break;
802 }
803 case JVM_SIGNATURE_BOOLEAN : {
804 jboolean b = obj->bool_field(offset);
805 writer->write_u1((u1)b);
806 break;
807 }
808 default : {
809 ShouldNotReachHere();
810 break;
811 }
812 }
813 }
814
815 // returns the size of the instance of the given class
816 u4 DumperSupport::instance_size(Klass* k) {
817 HandleMark hm;
818 InstanceKlass* ik = InstanceKlass::cast(k);
819
820 u4 size = 0;
821
822 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
823 if (!fld.access_flags().is_static()) {
824 Symbol* sig = fld.signature();
825 switch (sig->byte_at(0)) {
826 case JVM_SIGNATURE_CLASS :
827 case JVM_SIGNATURE_ARRAY : size += oopSize; break;
828
829 case JVM_SIGNATURE_BYTE :
830 case JVM_SIGNATURE_BOOLEAN : size += 1; break;
831
832 case JVM_SIGNATURE_CHAR :
833 case JVM_SIGNATURE_SHORT : size += 2; break;
834
835 case JVM_SIGNATURE_INT :
836 case JVM_SIGNATURE_FLOAT : size += 4; break;
837
838 case JVM_SIGNATURE_LONG :
839 case JVM_SIGNATURE_DOUBLE : size += 8; break;
840
841 default : ShouldNotReachHere();
842 }
843 }
844 }
845 return size;
846 }
847
848 // dumps static fields of the given class
849 void DumperSupport::dump_static_fields(DumpWriter* writer, Klass* k) {
850 HandleMark hm;
851 InstanceKlass* ik = InstanceKlass::cast(k);
852
853 // pass 1 - count the static fields
854 u2 field_count = 0;
855 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) {
856 if (fldc.access_flags().is_static()) field_count++;
857 }
858
859 // Add in resolved_references which is referenced by the cpCache
860 // The resolved_references is an array per InstanceKlass holding the
861 // strings and other oops resolved from the constant pool.
862 oop resolved_references = ik->constants()->resolved_references_or_null();
863 if (resolved_references != NULL) {
864 field_count++;
865
866 // Add in the resolved_references of the used previous versions of the class
867 // in the case of RedefineClasses
868 InstanceKlass* prev = ik->previous_versions();
869 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) {
870 field_count++;
871 prev = prev->previous_versions();
872 }
873 }
874
875 // Also provide a pointer to the init_lock if present, so there aren't unreferenced int[0]
876 // arrays.
877 oop init_lock = ik->init_lock();
878 if (init_lock != NULL) {
879 field_count++;
880 }
881
882 writer->write_u2(field_count);
883
884 // pass 2 - dump the field descriptors and raw values
885 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) {
886 if (fld.access_flags().is_static()) {
887 Symbol* sig = fld.signature();
888
889 writer->write_symbolID(fld.name()); // name
890 writer->write_u1(sig2tag(sig)); // type
891
892 // value
893 dump_field_value(writer, sig->byte_at(0), ik->java_mirror(), fld.offset());
894 }
895 }
896
897 // Add resolved_references for each class that has them
898 if (resolved_references != NULL) {
899 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
900 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
901 writer->write_objectID(resolved_references);
902
903 // Also write any previous versions
904 InstanceKlass* prev = ik->previous_versions();
905 while (prev != NULL && prev->constants()->resolved_references_or_null() != NULL) {
906 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
907 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
908 writer->write_objectID(prev->constants()->resolved_references());
909 prev = prev->previous_versions();
910 }
911 }
912
913 // Add init lock to the end if the class is not yet initialized
914 if (init_lock != NULL) {
915 writer->write_symbolID(vmSymbols::init_lock_name()); // name
916 writer->write_u1(sig2tag(vmSymbols::int_array_signature())); // type
917 writer->write_objectID(init_lock);
918 }
919 }
920
921 // dump the raw values of the instance fields of the given object
922 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) {
923 HandleMark hm;
924 InstanceKlass* ik = InstanceKlass::cast(o->klass());
925
926 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
927 if (!fld.access_flags().is_static()) {
928 Symbol* sig = fld.signature();
929 dump_field_value(writer, sig->byte_at(0), o, fld.offset());
930 }
931 }
932 }
933
934 // dumps the definition of the instance fields for a given class
935 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, Klass* k) {
936 HandleMark hm;
937 InstanceKlass* ik = InstanceKlass::cast(k);
938
939 // pass 1 - count the instance fields
940 u2 field_count = 0;
941 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) {
942 if (!fldc.access_flags().is_static()) field_count++;
943 }
944
945 writer->write_u2(field_count);
946
947 // pass 2 - dump the field descriptors
948 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) {
949 if (!fld.access_flags().is_static()) {
950 Symbol* sig = fld.signature();
951
952 writer->write_symbolID(fld.name()); // name
953 writer->write_u1(sig2tag(sig)); // type
954 }
955 }
956 }
957
958 // creates HPROF_GC_INSTANCE_DUMP record for the given object
959 void DumperSupport::dump_instance(DumpWriter* writer, oop o) {
960 Klass* k = o->klass();
961
962 writer->write_u1(HPROF_GC_INSTANCE_DUMP);
963 writer->write_objectID(o);
964 writer->write_u4(STACK_TRACE_ID);
965
966 // class ID
967 writer->write_classID(k);
968
969 // number of bytes that follow
970 writer->write_u4(instance_size(k) );
971
972 // field values
973 dump_instance_fields(writer, o);
974 }
975
976 // creates HPROF_GC_CLASS_DUMP record for the given class and each of
977 // its array classes
978 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, Klass* k) {
979 InstanceKlass* ik = InstanceKlass::cast(k);
980
981 // We can safepoint and do a heap dump at a point where we have a Klass,
982 // but no java mirror class has been setup for it. So we need to check
983 // that the class is at least loaded, to avoid crash from a null mirror.
984 if (!ik->is_loaded()) {
985 return;
986 }
987
988 writer->write_u1(HPROF_GC_CLASS_DUMP);
989
990 // class ID
991 writer->write_classID(ik);
992 writer->write_u4(STACK_TRACE_ID);
993
994 // super class ID
995 Klass* java_super = ik->java_super();
996 if (java_super == NULL) {
997 writer->write_objectID(oop(NULL));
998 } else {
999 writer->write_classID(java_super);
1000 }
1001
1002 writer->write_objectID(ik->class_loader());
1003 writer->write_objectID(ik->signers());
1004 writer->write_objectID(ik->protection_domain());
1005
1006 // reserved
1007 writer->write_objectID(oop(NULL));
1008 writer->write_objectID(oop(NULL));
1009
1010 // instance size
1011 writer->write_u4(DumperSupport::instance_size(k));
1012
1013 // size of constant pool - ignored by HAT 1.1
1014 writer->write_u2(0);
1015
1016 // number of static fields
1017 dump_static_fields(writer, k);
1018
1019 // description of instance fields
1020 dump_instance_field_descriptors(writer, k);
1021
1022 // array classes
1023 k = k->array_klass_or_null();
1024 while (k != NULL) {
1025 Klass* klass = k;
1026 assert(klass->is_objArray_klass(), "not an ObjArrayKlass");
1027
1028 writer->write_u1(HPROF_GC_CLASS_DUMP);
1029 writer->write_classID(klass);
1030 writer->write_u4(STACK_TRACE_ID);
1031
1032 // super class of array classes is java.lang.Object
1033 java_super = klass->java_super();
1034 assert(java_super != NULL, "checking");
1035 writer->write_classID(java_super);
1036
1037 writer->write_objectID(ik->class_loader());
1038 writer->write_objectID(ik->signers());
1039 writer->write_objectID(ik->protection_domain());
1040
1041 writer->write_objectID(oop(NULL)); // reserved
1042 writer->write_objectID(oop(NULL));
1043 writer->write_u4(0); // instance size
1044 writer->write_u2(0); // constant pool
1045 writer->write_u2(0); // static fields
1046 writer->write_u2(0); // instance fields
1047
1048 // get the array class for the next rank
1049 k = klass->array_klass_or_null();
1050 }
1051 }
1052
1053 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
1054 // class (and each multi-dimensional array class too)
1055 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, Klass* k) {
1056 // array classes
1057 while (k != NULL) {
1058 Klass* klass = k;
1059
1060 writer->write_u1(HPROF_GC_CLASS_DUMP);
1061 writer->write_classID(klass);
1062 writer->write_u4(STACK_TRACE_ID);
1063
1064 // super class of array classes is java.lang.Object
1065 Klass* java_super = klass->java_super();
1066 assert(java_super != NULL, "checking");
1067 writer->write_classID(java_super);
1068
1069 writer->write_objectID(oop(NULL)); // loader
1070 writer->write_objectID(oop(NULL)); // signers
1071 writer->write_objectID(oop(NULL)); // protection domain
1072
1073 writer->write_objectID(oop(NULL)); // reserved
1074 writer->write_objectID(oop(NULL));
1075 writer->write_u4(0); // instance size
1076 writer->write_u2(0); // constant pool
1077 writer->write_u2(0); // static fields
1078 writer->write_u2(0); // instance fields
1079
1080 // get the array class for the next rank
1081 k = klass->array_klass_or_null();
1082 }
1083 }
1084
1085 // Hprof uses an u4 as record length field,
1086 // which means we need to truncate arrays that are too long.
1087 int DumperSupport::calculate_array_max_length(DumpWriter* writer, arrayOop array, short header_size) {
1088 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1089 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
1090
1091 int length = array->length();
1092
1093 int type_size;
1094 if (type == T_OBJECT) {
1095 type_size = sizeof(address);
1096 } else {
1097 type_size = type2aelembytes(type);
1098 }
1099
1100 size_t length_in_bytes = (size_t)length * type_size;
1101
1102 // Create a new record if the current record is non-empty and the array can't fit.
1103 julong current_record_length = writer->current_record_length();
1104 if (current_record_length > 0 &&
1105 (current_record_length + header_size + length_in_bytes) > max_juint) {
1106 write_current_dump_record_length(writer);
1107 write_dump_header(writer);
1108
1109 // We now have an empty record.
1110 current_record_length = 0;
1111 }
1112
1113 // Calculate max bytes we can use.
1114 uint max_bytes = max_juint - (header_size + current_record_length);
1115
1116 // Array too long for the record?
1117 // Calculate max length and return it.
1118 if (length_in_bytes > max_bytes) {
1119 length = max_bytes / type_size;
1120 length_in_bytes = (size_t)length * type_size;
1121
1122 warning("cannot dump array of type %s[] with length %d; truncating to length %d",
1123 type2name_tab[type], array->length(), length);
1124 }
1125 return length;
1126 }
1127
1128 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1129 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) {
1130 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
1131 short header_size = 1 + 2 * 4 + 2 * sizeof(address);
1132
1133 int length = calculate_array_max_length(writer, array, header_size);
1134
1135 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP);
1136 writer->write_objectID(array);
1137 writer->write_u4(STACK_TRACE_ID);
1138 writer->write_u4(length);
1139
1140 // array class ID
1141 writer->write_classID(array->klass());
1142
1143 // [id]* elements
1144 for (int index = 0; index < length; index++) {
1145 oop o = array->obj_at(index);
1146 writer->write_objectID(o);
1147 }
1148 }
1149
1150 #define WRITE_ARRAY(Array, Type, Size, Length) \
1151 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
1152
1153 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1154 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) {
1155 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1156
1157 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID)
1158 short header_size = 2 * 1 + 2 * 4 + sizeof(address);
1159
1160 int length = calculate_array_max_length(writer, array, header_size);
1161 int type_size = type2aelembytes(type);
1162 u4 length_in_bytes = (u4)length * type_size;
1163
1164 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP);
1165 writer->write_objectID(array);
1166 writer->write_u4(STACK_TRACE_ID);
1167 writer->write_u4(length);
1168 writer->write_u1(type2tag(type));
1169
1170 // nothing to copy
1171 if (length == 0) {
1172 return;
1173 }
1174
1175 // If the byte ordering is big endian then we can copy most types directly
1176
1177 switch (type) {
1178 case T_INT : {
1179 if (Endian::is_Java_byte_ordering_different()) {
1180 WRITE_ARRAY(array, int, u4, length);
1181 } else {
1182 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes);
1183 }
1184 break;
1185 }
1186 case T_BYTE : {
1187 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes);
1188 break;
1189 }
1190 case T_CHAR : {
1191 if (Endian::is_Java_byte_ordering_different()) {
1192 WRITE_ARRAY(array, char, u2, length);
1193 } else {
1194 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes);
1195 }
1196 break;
1197 }
1198 case T_SHORT : {
1199 if (Endian::is_Java_byte_ordering_different()) {
1200 WRITE_ARRAY(array, short, u2, length);
1201 } else {
1202 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes);
1203 }
1204 break;
1205 }
1206 case T_BOOLEAN : {
1207 if (Endian::is_Java_byte_ordering_different()) {
1208 WRITE_ARRAY(array, bool, u1, length);
1209 } else {
1210 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes);
1211 }
1212 break;
1213 }
1214 case T_LONG : {
1215 if (Endian::is_Java_byte_ordering_different()) {
1216 WRITE_ARRAY(array, long, u8, length);
1217 } else {
1218 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes);
1219 }
1220 break;
1221 }
1222
1223 // handle float/doubles in a special value to ensure than NaNs are
1224 // written correctly. TO DO: Check if we can avoid this on processors that
1225 // use IEEE 754.
1226
1227 case T_FLOAT : {
1228 for (int i = 0; i < length; i++) {
1229 dump_float(writer, array->float_at(i));
1230 }
1231 break;
1232 }
1233 case T_DOUBLE : {
1234 for (int i = 0; i < length; i++) {
1235 dump_double(writer, array->double_at(i));
1236 }
1237 break;
1238 }
1239 default : ShouldNotReachHere();
1240 }
1241 }
1242
1243 // create a HPROF_FRAME record of the given Method* and bci
1244 void DumperSupport::dump_stack_frame(DumpWriter* writer,
1245 int frame_serial_num,
1246 int class_serial_num,
1247 Method* m,
1248 int bci) {
1249 int line_number;
1250 if (m->is_native()) {
1251 line_number = -3; // native frame
1252 } else {
1253 line_number = m->line_number_from_bci(bci);
1254 }
1255
1256 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1257 writer->write_id(frame_serial_num); // frame serial number
1258 writer->write_symbolID(m->name()); // method's name
1259 writer->write_symbolID(m->signature()); // method's signature
1260
1261 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass");
1262 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1263 writer->write_u4(class_serial_num); // class serial number
1264 writer->write_u4((u4) line_number); // line number
1265 }
1266
1267
1268 // Support class used to generate HPROF_UTF8 records from the entries in the
1269 // SymbolTable.
1270
1271 class SymbolTableDumper : public SymbolClosure {
1272 private:
1273 DumpWriter* _writer;
1274 DumpWriter* writer() const { return _writer; }
1275 public:
1276 SymbolTableDumper(DumpWriter* writer) { _writer = writer; }
1277 void do_symbol(Symbol** p);
1278 };
1279
1280 void SymbolTableDumper::do_symbol(Symbol** p) {
1281 ResourceMark rm;
1282 Symbol* sym = load_symbol(p);
1283 int len = sym->utf8_length();
1284 if (len > 0) {
1285 char* s = sym->as_utf8();
1286 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1287 writer()->write_symbolID(sym);
1288 writer()->write_raw(s, len);
1289 }
1290 }
1291
1292 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
1293
1294 class JNILocalsDumper : public OopClosure {
1295 private:
1296 DumpWriter* _writer;
1297 u4 _thread_serial_num;
1298 int _frame_num;
1299 DumpWriter* writer() const { return _writer; }
1300 public:
1301 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) {
1302 _writer = writer;
1303 _thread_serial_num = thread_serial_num;
1304 _frame_num = -1; // default - empty stack
1305 }
1306 void set_frame_number(int n) { _frame_num = n; }
1307 void do_oop(oop* obj_p);
1308 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1309 };
1310
1311
1312 void JNILocalsDumper::do_oop(oop* obj_p) {
1313 // ignore null handles
1314 oop o = *obj_p;
1315 if (o != NULL) {
1316 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL);
1317 writer()->write_objectID(o);
1318 writer()->write_u4(_thread_serial_num);
1319 writer()->write_u4((u4)_frame_num);
1320 }
1321 }
1322
1323
1324 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
1325
1326 class JNIGlobalsDumper : public OopClosure {
1327 private:
1328 DumpWriter* _writer;
1329 DumpWriter* writer() const { return _writer; }
1330
1331 public:
1332 JNIGlobalsDumper(DumpWriter* writer) {
1333 _writer = writer;
1334 }
1335 void do_oop(oop* obj_p);
1336 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1337 };
1338
1339 void JNIGlobalsDumper::do_oop(oop* obj_p) {
1340 oop o = *obj_p;
1341
1342 // ignore these
1343 if (o == NULL) return;
1344
1345 // we ignore global ref to symbols and other internal objects
1346 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) {
1347 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL);
1348 writer()->write_objectID(o);
1349 writer()->write_objectID((oopDesc*)obj_p); // global ref ID
1350 }
1351 };
1352
1353
1354 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records
1355
1356 class MonitorUsedDumper : public OopClosure {
1357 private:
1358 DumpWriter* _writer;
1359 DumpWriter* writer() const { return _writer; }
1360 public:
1361 MonitorUsedDumper(DumpWriter* writer) {
1362 _writer = writer;
1363 }
1364 void do_oop(oop* obj_p) {
1365 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED);
1366 writer()->write_objectID(*obj_p);
1367 }
1368 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1369 };
1370
1371
1372 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
1373
1374 class StickyClassDumper : public KlassClosure {
1375 private:
1376 DumpWriter* _writer;
1377 DumpWriter* writer() const { return _writer; }
1378 public:
1379 StickyClassDumper(DumpWriter* writer) {
1380 _writer = writer;
1381 }
1382 void do_klass(Klass* k) {
1383 if (k->is_instance_klass()) {
1384 InstanceKlass* ik = InstanceKlass::cast(k);
1385 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS);
1386 writer()->write_classID(ik);
1387 }
1388 }
1389 };
1390
1391
1392 class VM_HeapDumper;
1393
1394 // Support class using when iterating over the heap.
1395
1396 class HeapObjectDumper : public ObjectClosure {
1397 private:
1398 VM_HeapDumper* _dumper;
1399 DumpWriter* _writer;
1400
1401 VM_HeapDumper* dumper() { return _dumper; }
1402 DumpWriter* writer() { return _writer; }
1403
1404 // used to indicate that a record has been writen
1405 void mark_end_of_record();
1406
1407 public:
1408 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) {
1409 _dumper = dumper;
1410 _writer = writer;
1411 }
1412
1413 // called for each object in the heap
1414 void do_object(oop o);
1415 };
1416
1417 void HeapObjectDumper::do_object(oop o) {
1418 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records
1419 if (o->klass() == SystemDictionary::Class_klass()) {
1420 if (!java_lang_Class::is_primitive(o)) {
1421 return;
1422 }
1423 }
1424
1425 if (o->is_instance()) {
1426 // create a HPROF_GC_INSTANCE record for each object
1427 DumperSupport::dump_instance(writer(), o);
1428 mark_end_of_record();
1429 } else if (o->is_objArray()) {
1430 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
1431 DumperSupport::dump_object_array(writer(), objArrayOop(o));
1432 mark_end_of_record();
1433 } else if (o->is_typeArray()) {
1434 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
1435 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
1436 mark_end_of_record();
1437 }
1438 }
1439
1440 // The VM operation that performs the heap dump
1441 class VM_HeapDumper : public VM_GC_Operation {
1442 private:
1443 static VM_HeapDumper* _global_dumper;
1444 static DumpWriter* _global_writer;
1445 DumpWriter* _local_writer;
1446 JavaThread* _oome_thread;
1447 Method* _oome_constructor;
1448 bool _gc_before_heap_dump;
1449 GrowableArray<Klass*>* _klass_map;
1450 ThreadStackTrace** _stack_traces;
1451 int _num_threads;
1452
1453 // accessors and setters
1454 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; }
1455 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; }
1456 void set_global_dumper() {
1457 assert(_global_dumper == NULL, "Error");
1458 _global_dumper = this;
1459 }
1460 void set_global_writer() {
1461 assert(_global_writer == NULL, "Error");
1462 _global_writer = _local_writer;
1463 }
1464 void clear_global_dumper() { _global_dumper = NULL; }
1465 void clear_global_writer() { _global_writer = NULL; }
1466
1467 bool skip_operation() const;
1468
1469 // writes a HPROF_LOAD_CLASS record
1470 static void do_load_class(Klass* k);
1471
1472 // writes a HPROF_GC_CLASS_DUMP record for the given class
1473 // (and each array class too)
1474 static void do_class_dump(Klass* k);
1475
1476 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1477 // array (and each multi-dimensional array too)
1478 static void do_basic_type_array_class_dump(Klass* k);
1479
1480 // HPROF_GC_ROOT_THREAD_OBJ records
1481 int do_thread(JavaThread* thread, u4 thread_serial_num);
1482 void do_threads();
1483
1484 void add_class_serial_number(Klass* k, int serial_num) {
1485 _klass_map->at_put_grow(serial_num, k);
1486 }
1487
1488 // HPROF_TRACE and HPROF_FRAME records
1489 void dump_stack_traces();
1490
1491 public:
1492 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) :
1493 VM_GC_Operation(0 /* total collections, dummy, ignored */,
1494 GCCause::_heap_dump /* GC Cause */,
1495 0 /* total full collections, dummy, ignored */,
1496 gc_before_heap_dump) {
1497 _local_writer = writer;
1498 _gc_before_heap_dump = gc_before_heap_dump;
1499 _klass_map = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true);
1500 _stack_traces = NULL;
1501 _num_threads = 0;
1502 if (oome) {
1503 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread");
1504 // get OutOfMemoryError zero-parameter constructor
1505 InstanceKlass* oome_ik = SystemDictionary::OutOfMemoryError_klass();
1506 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(),
1507 vmSymbols::void_method_signature());
1508 // get thread throwing OOME when generating the heap dump at OOME
1509 _oome_thread = JavaThread::current();
1510 } else {
1511 _oome_thread = NULL;
1512 _oome_constructor = NULL;
1513 }
1514 }
1515 ~VM_HeapDumper() {
1516 if (_stack_traces != NULL) {
1517 for (int i=0; i < _num_threads; i++) {
1518 delete _stack_traces[i];
1519 }
1520 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces);
1521 }
1522 delete _klass_map;
1523 }
1524
1525 VMOp_Type type() const { return VMOp_HeapDumper; }
1526 // used to mark sub-record boundary
1527 void check_segment_length();
1528 void doit();
1529 };
1530
1531 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL;
1532 DumpWriter* VM_HeapDumper::_global_writer = NULL;
1533
1534 bool VM_HeapDumper::skip_operation() const {
1535 return false;
1536 }
1537
1538 // writes a HPROF_HEAP_DUMP_SEGMENT record
1539 void DumperSupport::write_dump_header(DumpWriter* writer) {
1540 if (writer->is_open()) {
1541 writer->write_u1(HPROF_HEAP_DUMP_SEGMENT);
1542 writer->write_u4(0); // current ticks
1543
1544 // record the starting position for the dump (its length will be fixed up later)
1545 writer->set_dump_start(writer->current_offset());
1546 writer->write_u4(0);
1547 }
1548 }
1549
1550 // fixes up the length of the current dump record
1551 void DumperSupport::write_current_dump_record_length(DumpWriter* writer) {
1552 if (writer->is_open()) {
1553 julong dump_end = writer->bytes_written() + writer->bytes_unwritten();
1554 julong dump_len = writer->current_record_length();
1555
1556 // record length must fit in a u4
1557 if (dump_len > max_juint) {
1558 warning("record is too large");
1559 }
1560
1561 // seek to the dump start and fix-up the length
1562 assert(writer->dump_start() >= 0, "no dump start recorded");
1563 writer->seek_to_offset(writer->dump_start());
1564 writer->write_u4((u4)dump_len);
1565
1566 // adjust the total size written to keep the bytes written correct.
1567 writer->adjust_bytes_written(-((jlong) sizeof(u4)));
1568
1569 // seek to dump end so we can continue
1570 writer->seek_to_offset(dump_end);
1571
1572 // no current dump record
1573 writer->set_dump_start((jlong)-1);
1574 }
1575 }
1576
1577 // used on a sub-record boundary to check if we need to start a
1578 // new segment.
1579 void VM_HeapDumper::check_segment_length() {
1580 if (writer()->is_open()) {
1581 julong dump_len = writer()->current_record_length();
1582
1583 if (dump_len > 2UL*G) {
1584 DumperSupport::write_current_dump_record_length(writer());
1585 DumperSupport::write_dump_header(writer());
1586 }
1587 }
1588 }
1589
1590 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
1591 void DumperSupport::end_of_dump(DumpWriter* writer) {
1592 if (writer->is_open()) {
1593 write_current_dump_record_length(writer);
1594
1595 writer->write_u1(HPROF_HEAP_DUMP_END);
1596 writer->write_u4(0);
1597 writer->write_u4(0);
1598 }
1599 }
1600
1601 // marks sub-record boundary
1602 void HeapObjectDumper::mark_end_of_record() {
1603 dumper()->check_segment_length();
1604 }
1605
1606 // writes a HPROF_LOAD_CLASS record for the class (and each of its
1607 // array classes)
1608 void VM_HeapDumper::do_load_class(Klass* k) {
1609 static u4 class_serial_num = 0;
1610
1611 // len of HPROF_LOAD_CLASS record
1612 u4 remaining = 2*oopSize + 2*sizeof(u4);
1613
1614 // write a HPROF_LOAD_CLASS for the class and each array class
1615 do {
1616 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
1617
1618 // class serial number is just a number
1619 writer()->write_u4(++class_serial_num);
1620
1621 // class ID
1622 Klass* klass = k;
1623 writer()->write_classID(klass);
1624
1625 // add the Klass* and class serial number pair
1626 dumper()->add_class_serial_number(klass, class_serial_num);
1627
1628 writer()->write_u4(STACK_TRACE_ID);
1629
1630 // class name ID
1631 Symbol* name = klass->name();
1632 writer()->write_symbolID(name);
1633
1634 // write a LOAD_CLASS record for the array type (if it exists)
1635 k = klass->array_klass_or_null();
1636 } while (k != NULL);
1637 }
1638
1639 // writes a HPROF_GC_CLASS_DUMP record for the given class
1640 void VM_HeapDumper::do_class_dump(Klass* k) {
1641 if (k->is_instance_klass()) {
1642 DumperSupport::dump_class_and_array_classes(writer(), k);
1643 }
1644 }
1645
1646 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1647 // array (and each multi-dimensional array too)
1648 void VM_HeapDumper::do_basic_type_array_class_dump(Klass* k) {
1649 DumperSupport::dump_basic_type_array_class(writer(), k);
1650 }
1651
1652 // Walk the stack of the given thread.
1653 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local
1654 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local
1655 //
1656 // It returns the number of Java frames in this thread stack
1657 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) {
1658 JNILocalsDumper blk(writer(), thread_serial_num);
1659
1660 oop threadObj = java_thread->threadObj();
1661 assert(threadObj != NULL, "sanity check");
1662
1663 int stack_depth = 0;
1664 if (java_thread->has_last_Java_frame()) {
1665
1666 // vframes are resource allocated
1667 Thread* current_thread = Thread::current();
1668 ResourceMark rm(current_thread);
1669 HandleMark hm(current_thread);
1670
1671 RegisterMap reg_map(java_thread);
1672 frame f = java_thread->last_frame();
1673 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread);
1674 frame* last_entry_frame = NULL;
1675 int extra_frames = 0;
1676
1677 if (java_thread == _oome_thread && _oome_constructor != NULL) {
1678 extra_frames++;
1679 }
1680 while (vf != NULL) {
1681 blk.set_frame_number(stack_depth);
1682 if (vf->is_java_frame()) {
1683
1684 // java frame (interpreted, compiled, ...)
1685 javaVFrame *jvf = javaVFrame::cast(vf);
1686 if (!(jvf->method()->is_native())) {
1687 StackValueCollection* locals = jvf->locals();
1688 for (int slot=0; slot<locals->size(); slot++) {
1689 if (locals->at(slot)->type() == T_OBJECT) {
1690 oop o = locals->obj_at(slot)();
1691
1692 if (o != NULL) {
1693 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1694 writer()->write_objectID(o);
1695 writer()->write_u4(thread_serial_num);
1696 writer()->write_u4((u4) (stack_depth + extra_frames));
1697 }
1698 }
1699 }
1700 StackValueCollection *exprs = jvf->expressions();
1701 for(int index = 0; index < exprs->size(); index++) {
1702 if (exprs->at(index)->type() == T_OBJECT) {
1703 oop o = exprs->obj_at(index)();
1704 if (o != NULL) {
1705 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1706 writer()->write_objectID(o);
1707 writer()->write_u4(thread_serial_num);
1708 writer()->write_u4((u4) (stack_depth + extra_frames));
1709 }
1710 }
1711 }
1712 } else {
1713 // native frame
1714 if (stack_depth == 0) {
1715 // JNI locals for the top frame.
1716 java_thread->active_handles()->oops_do(&blk);
1717 } else {
1718 if (last_entry_frame != NULL) {
1719 // JNI locals for the entry frame
1720 assert(last_entry_frame->is_entry_frame(), "checking");
1721 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk);
1722 }
1723 }
1724 }
1725 // increment only for Java frames
1726 stack_depth++;
1727 last_entry_frame = NULL;
1728
1729 } else {
1730 // externalVFrame - if it's an entry frame then report any JNI locals
1731 // as roots when we find the corresponding native javaVFrame
1732 frame* fr = vf->frame_pointer();
1733 assert(fr != NULL, "sanity check");
1734 if (fr->is_entry_frame()) {
1735 last_entry_frame = fr;
1736 }
1737 }
1738 vf = vf->sender();
1739 }
1740 } else {
1741 // no last java frame but there may be JNI locals
1742 java_thread->active_handles()->oops_do(&blk);
1743 }
1744 return stack_depth;
1745 }
1746
1747
1748 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk
1749 // the stack so that locals and JNI locals are dumped.
1750 void VM_HeapDumper::do_threads() {
1751 for (int i=0; i < _num_threads; i++) {
1752 JavaThread* thread = _stack_traces[i]->thread();
1753 oop threadObj = thread->threadObj();
1754 u4 thread_serial_num = i+1;
1755 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID;
1756 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ);
1757 writer()->write_objectID(threadObj);
1758 writer()->write_u4(thread_serial_num); // thread number
1759 writer()->write_u4(stack_serial_num); // stack trace serial number
1760 int num_frames = do_thread(thread, thread_serial_num);
1761 assert(num_frames == _stack_traces[i]->get_stack_depth(),
1762 "total number of Java frames not matched");
1763 }
1764 }
1765
1766
1767 // The VM operation that dumps the heap. The dump consists of the following
1768 // records:
1769 //
1770 // HPROF_HEADER
1771 // [HPROF_UTF8]*
1772 // [HPROF_LOAD_CLASS]*
1773 // [[HPROF_FRAME]*|HPROF_TRACE]*
1774 // [HPROF_GC_CLASS_DUMP]*
1775 // [HPROF_HEAP_DUMP_SEGMENT]*
1776 // HPROF_HEAP_DUMP_END
1777 //
1778 // The HPROF_TRACE records represent the stack traces where the heap dump
1779 // is generated and a "dummy trace" record which does not include
1780 // any frames. The dummy trace record is used to be referenced as the
1781 // unknown object alloc site.
1782 //
1783 // Each HPROF_HEAP_DUMP_SEGMENT record has a length followed by sub-records.
1784 // To allow the heap dump be generated in a single pass we remember the position
1785 // of the dump length and fix it up after all sub-records have been written.
1786 // To generate the sub-records we iterate over the heap, writing
1787 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP
1788 // records as we go. Once that is done we write records for some of the GC
1789 // roots.
1790
1791 void VM_HeapDumper::doit() {
1792
1793 HandleMark hm;
1794 CollectedHeap* ch = Universe::heap();
1795
1796 ch->ensure_parsability(false); // must happen, even if collection does
1797 // not happen (e.g. due to GCLocker)
1798
1799 if (_gc_before_heap_dump) {
1800 if (GCLocker::is_active()) {
1801 warning("GC locker is held; pre-heapdump GC was skipped");
1802 } else {
1803 ch->collect_as_vm_thread(GCCause::_heap_dump);
1804 }
1805 }
1806
1807 // At this point we should be the only dumper active, so
1808 // the following should be safe.
1809 set_global_dumper();
1810 set_global_writer();
1811
1812 // Write the file header - we always use 1.0.2
1813 size_t used = ch->used();
1814 const char* header = "JAVA PROFILE 1.0.2";
1815
1816 // header is few bytes long - no chance to overflow int
1817 writer()->write_raw((void*)header, (int)strlen(header));
1818 writer()->write_u1(0); // terminator
1819 writer()->write_u4(oopSize);
1820 writer()->write_u8(os::javaTimeMillis());
1821
1822 // HPROF_UTF8 records
1823 SymbolTableDumper sym_dumper(writer());
1824 SymbolTable::symbols_do(&sym_dumper);
1825
1826 // write HPROF_LOAD_CLASS records
1827 ClassLoaderDataGraph::classes_do(&do_load_class);
1828 Universe::basic_type_classes_do(&do_load_class);
1829
1830 // write HPROF_FRAME and HPROF_TRACE records
1831 // this must be called after _klass_map is built when iterating the classes above.
1832 dump_stack_traces();
1833
1834 // write HPROF_HEAP_DUMP_SEGMENT
1835 DumperSupport::write_dump_header(writer());
1836
1837 // Writes HPROF_GC_CLASS_DUMP records
1838 ClassLoaderDataGraph::classes_do(&do_class_dump);
1839 Universe::basic_type_classes_do(&do_basic_type_array_class_dump);
1840 check_segment_length();
1841
1842 // writes HPROF_GC_INSTANCE_DUMP records.
1843 // After each sub-record is written check_segment_length will be invoked
1844 // to check if the current segment exceeds a threshold. If so, a new
1845 // segment is started.
1846 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk
1847 // of the heap dump.
1848 HeapObjectDumper obj_dumper(this, writer());
1849 Universe::heap()->safe_object_iterate(&obj_dumper);
1850
1851 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
1852 do_threads();
1853 check_segment_length();
1854
1855 // HPROF_GC_ROOT_MONITOR_USED
1856 MonitorUsedDumper mon_dumper(writer());
1857 ObjectSynchronizer::oops_do(&mon_dumper);
1858 check_segment_length();
1859
1860 // HPROF_GC_ROOT_JNI_GLOBAL
1861 JNIGlobalsDumper jni_dumper(writer());
1862 JNIHandles::oops_do(&jni_dumper);
1863 Universe::oops_do(&jni_dumper); // technically not jni roots, but global roots
1864 // for things like preallocated throwable backtraces
1865 check_segment_length();
1866
1867 // HPROF_GC_ROOT_STICKY_CLASS
1868 // These should be classes in the NULL class loader data, and not all classes
1869 // if !ClassUnloading
1870 StickyClassDumper class_dumper(writer());
1871 ClassLoaderData::the_null_class_loader_data()->classes_do(&class_dumper);
1872
1873 // fixes up the length of the dump record and writes the HPROF_HEAP_DUMP_END record.
1874 DumperSupport::end_of_dump(writer());
1875
1876 // Now we clear the global variables, so that a future dumper might run.
1877 clear_global_dumper();
1878 clear_global_writer();
1879 }
1880
1881 void VM_HeapDumper::dump_stack_traces() {
1882 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites
1883 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4));
1884 writer()->write_u4((u4) STACK_TRACE_ID);
1885 writer()->write_u4(0); // thread number
1886 writer()->write_u4(0); // frame count
1887
1888 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal);
1889 int frame_serial_num = 0;
1890 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
1891 oop threadObj = thread->threadObj();
1892 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) {
1893 // dump thread stack trace
1894 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false);
1895 stack_trace->dump_stack_at_safepoint(-1);
1896 _stack_traces[_num_threads++] = stack_trace;
1897
1898 // write HPROF_FRAME records for this thread's stack trace
1899 int depth = stack_trace->get_stack_depth();
1900 int thread_frame_start = frame_serial_num;
1901 int extra_frames = 0;
1902 // write fake frame that makes it look like the thread, which caused OOME,
1903 // is in the OutOfMemoryError zero-parameter constructor
1904 if (thread == _oome_thread && _oome_constructor != NULL) {
1905 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder());
1906 // the class serial number starts from 1
1907 assert(oome_serial_num > 0, "OutOfMemoryError class not found");
1908 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num,
1909 _oome_constructor, 0);
1910 extra_frames++;
1911 }
1912 for (int j=0; j < depth; j++) {
1913 StackFrameInfo* frame = stack_trace->stack_frame_at(j);
1914 Method* m = frame->method();
1915 int class_serial_num = _klass_map->find(m->method_holder());
1916 // the class serial number starts from 1
1917 assert(class_serial_num > 0, "class not found");
1918 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci());
1919 }
1920 depth += extra_frames;
1921
1922 // write HPROF_TRACE record for one thread
1923 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize);
1924 int stack_serial_num = _num_threads + STACK_TRACE_ID;
1925 writer()->write_u4(stack_serial_num); // stack trace serial number
1926 writer()->write_u4((u4) _num_threads); // thread serial number
1927 writer()->write_u4(depth); // frame count
1928 for (int j=1; j <= depth; j++) {
1929 writer()->write_id(thread_frame_start + j);
1930 }
1931 }
1932 }
1933 }
1934
1935 // dump the heap to given path.
1936 int HeapDumper::dump(const char* path) {
1937 assert(path != NULL && strlen(path) > 0, "path missing");
1938
1939 // print message in interactive case
1940 if (print_to_tty()) {
1941 tty->print_cr("Dumping heap to %s ...", path);
1942 timer()->start();
1943 }
1944
1945 // create the dump writer. If the file can be opened then bail
1946 DumpWriter writer(path);
1947 if (!writer.is_open()) {
1948 set_error(writer.error());
1949 if (print_to_tty()) {
1950 tty->print_cr("Unable to create %s: %s", path,
1951 (error() != NULL) ? error() : "reason unknown");
1952 }
1953 return -1;
1954 }
1955
1956 // generate the dump
1957 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome);
1958 if (Thread::current()->is_VM_thread()) {
1959 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint");
1960 dumper.doit();
1961 } else {
1962 VMThread::execute(&dumper);
1963 }
1964
1965 // close dump file and record any error that the writer may have encountered
1966 writer.close();
1967 set_error(writer.error());
1968
1969 // print message in interactive case
1970 if (print_to_tty()) {
1971 timer()->stop();
1972 if (error() == NULL) {
1973 tty->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]",
1974 writer.bytes_written(), timer()->seconds());
1975 } else {
1976 tty->print_cr("Dump file is incomplete: %s", writer.error());
1977 }
1978 }
1979
1980 return (writer.error() == NULL) ? 0 : -1;
1981 }
1982
1983 // stop timer (if still active), and free any error string we might be holding
1984 HeapDumper::~HeapDumper() {
1985 if (timer()->is_active()) {
1986 timer()->stop();
1987 }
1988 set_error(NULL);
1989 }
1990
1991
1992 // returns the error string (resource allocated), or NULL
1993 char* HeapDumper::error_as_C_string() const {
1994 if (error() != NULL) {
1995 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1);
1996 strcpy(str, error());
1997 return str;
1998 } else {
1999 return NULL;
2000 }
2001 }
2002
2003 // set the error string
2004 void HeapDumper::set_error(char* error) {
2005 if (_error != NULL) {
2006 os::free(_error);
2007 }
2008 if (error == NULL) {
2009 _error = NULL;
2010 } else {
2011 _error = os::strdup(error);
2012 assert(_error != NULL, "allocation failure");
2013 }
2014 }
2015
2016 // Called by out-of-memory error reporting by a single Java thread
2017 // outside of a JVM safepoint
2018 void HeapDumper::dump_heap_from_oome() {
2019 HeapDumper::dump_heap(true);
2020 }
2021
2022 // Called by error reporting by a single Java thread outside of a JVM safepoint,
2023 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various
2024 // callers are strictly serialized and guaranteed not to interfere below. For more
2025 // general use, however, this method will need modification to prevent
2026 // inteference when updating the static variables base_path and dump_file_seq below.
2027 void HeapDumper::dump_heap() {
2028 HeapDumper::dump_heap(false);
2029 }
2030
2031 void HeapDumper::dump_heap(bool oome) {
2032 static char base_path[JVM_MAXPATHLEN] = {'\0'};
2033 static uint dump_file_seq = 0;
2034 char* my_path;
2035 const int max_digit_chars = 20;
2036
2037 const char* dump_file_name = "java_pid";
2038 const char* dump_file_ext = ".hprof";
2039
2040 // The dump file defaults to java_pid<pid>.hprof in the current working
2041 // directory. HeapDumpPath=<file> can be used to specify an alternative
2042 // dump file name or a directory where dump file is created.
2043 if (dump_file_seq == 0) { // first time in, we initialize base_path
2044 // Calculate potentially longest base path and check if we have enough
2045 // allocated statically.
2046 const size_t total_length =
2047 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) +
2048 strlen(os::file_separator()) + max_digit_chars +
2049 strlen(dump_file_name) + strlen(dump_file_ext) + 1;
2050 if (total_length > sizeof(base_path)) {
2051 warning("Cannot create heap dump file. HeapDumpPath is too long.");
2052 return;
2053 }
2054
2055 bool use_default_filename = true;
2056 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') {
2057 // HeapDumpPath=<file> not specified
2058 } else {
2059 strcpy(base_path, HeapDumpPath);
2060 // check if the path is a directory (must exist)
2061 DIR* dir = os::opendir(base_path);
2062 if (dir == NULL) {
2063 use_default_filename = false;
2064 } else {
2065 // HeapDumpPath specified a directory. We append a file separator
2066 // (if needed).
2067 os::closedir(dir);
2068 size_t fs_len = strlen(os::file_separator());
2069 if (strlen(base_path) >= fs_len) {
2070 char* end = base_path;
2071 end += (strlen(base_path) - fs_len);
2072 if (strcmp(end, os::file_separator()) != 0) {
2073 strcat(base_path, os::file_separator());
2074 }
2075 }
2076 }
2077 }
2078 // If HeapDumpPath wasn't a file name then we append the default name
2079 if (use_default_filename) {
2080 const size_t dlen = strlen(base_path); // if heap dump dir specified
2081 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s",
2082 dump_file_name, os::current_process_id(), dump_file_ext);
2083 }
2084 const size_t len = strlen(base_path) + 1;
2085 my_path = (char*)os::malloc(len, mtInternal);
2086 if (my_path == NULL) {
2087 warning("Cannot create heap dump file. Out of system memory.");
2088 return;
2089 }
2090 strncpy(my_path, base_path, len);
2091 } else {
2092 // Append a sequence number id for dumps following the first
2093 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0
2094 my_path = (char*)os::malloc(len, mtInternal);
2095 if (my_path == NULL) {
2096 warning("Cannot create heap dump file. Out of system memory.");
2097 return;
2098 }
2099 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq);
2100 }
2101 dump_file_seq++; // increment seq number for next time we dump
2102
2103 HeapDumper dumper(false /* no GC before heap dump */,
2104 true /* send to tty */,
2105 oome /* pass along out-of-memory-error flag */);
2106 dumper.dump(my_path);
2107 os::free(my_path);
2108 }