Sun, 03 Feb 2013 22:28:08 +0400
8002048: Protocol to discovery of manageable Java processes on a network
Summary: Introduce a protocol to discover manageble Java instances across a network subnet, JDP
Reviewed-by: sla, dfuchs
1 /*
2 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/vmSymbols.hpp"
29 #include "gc_implementation/shared/vmGCOperations.hpp"
30 #include "memory/gcLocker.inline.hpp"
31 #include "memory/genCollectedHeap.hpp"
32 #include "memory/universe.hpp"
33 #include "oops/objArrayKlass.hpp"
34 #include "runtime/javaCalls.hpp"
35 #include "runtime/jniHandles.hpp"
36 #include "runtime/reflectionUtils.hpp"
37 #include "runtime/vframe.hpp"
38 #include "runtime/vmThread.hpp"
39 #include "runtime/vm_operations.hpp"
40 #include "services/heapDumper.hpp"
41 #include "services/threadService.hpp"
42 #include "utilities/ostream.hpp"
43 #ifndef SERIALGC
44 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
45 #endif
47 /*
48 * HPROF binary format - description copied from:
49 * src/share/demo/jvmti/hprof/hprof_io.c
50 *
51 *
52 * header "JAVA PROFILE 1.0.1" or "JAVA PROFILE 1.0.2"
53 * (0-terminated)
54 *
55 * u4 size of identifiers. Identifiers are used to represent
56 * UTF8 strings, objects, stack traces, etc. They usually
57 * have the same size as host pointers. For example, on
58 * Solaris and Win32, the size is 4.
59 * u4 high word
60 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70
61 * [record]* a sequence of records.
62 *
63 *
64 * Record format:
65 *
66 * u1 a TAG denoting the type of the record
67 * u4 number of *microseconds* since the time stamp in the
68 * header. (wraps around in a little more than an hour)
69 * u4 number of bytes *remaining* in the record. Note that
70 * this number excludes the tag and the length field itself.
71 * [u1]* BODY of the record (a sequence of bytes)
72 *
73 *
74 * The following TAGs are supported:
75 *
76 * TAG BODY notes
77 *----------------------------------------------------------
78 * HPROF_UTF8 a UTF8-encoded name
79 *
80 * id name ID
81 * [u1]* UTF8 characters (no trailing zero)
82 *
83 * HPROF_LOAD_CLASS a newly loaded class
84 *
85 * u4 class serial number (> 0)
86 * id class object ID
87 * u4 stack trace serial number
88 * id class name ID
89 *
90 * HPROF_UNLOAD_CLASS an unloading class
91 *
92 * u4 class serial_number
93 *
94 * HPROF_FRAME a Java stack frame
95 *
96 * id stack frame ID
97 * id method name ID
98 * id method signature ID
99 * id source file name ID
100 * u4 class serial number
101 * i4 line number. >0: normal
102 * -1: unknown
103 * -2: compiled method
104 * -3: native method
105 *
106 * HPROF_TRACE a Java stack trace
107 *
108 * u4 stack trace serial number
109 * u4 thread serial number
110 * u4 number of frames
111 * [id]* stack frame IDs
112 *
113 *
114 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC
115 *
116 * u2 flags 0x0001: incremental vs. complete
117 * 0x0002: sorted by allocation vs. live
118 * 0x0004: whether to force a GC
119 * u4 cutoff ratio
120 * u4 total live bytes
121 * u4 total live instances
122 * u8 total bytes allocated
123 * u8 total instances allocated
124 * u4 number of sites that follow
125 * [u1 is_array: 0: normal object
126 * 2: object array
127 * 4: boolean array
128 * 5: char array
129 * 6: float array
130 * 7: double array
131 * 8: byte array
132 * 9: short array
133 * 10: int array
134 * 11: long array
135 * u4 class serial number (may be zero during startup)
136 * u4 stack trace serial number
137 * u4 number of bytes alive
138 * u4 number of instances alive
139 * u4 number of bytes allocated
140 * u4]* number of instance allocated
141 *
142 * HPROF_START_THREAD a newly started thread.
143 *
144 * u4 thread serial number (> 0)
145 * id thread object ID
146 * u4 stack trace serial number
147 * id thread name ID
148 * id thread group name ID
149 * id thread group parent name ID
150 *
151 * HPROF_END_THREAD a terminating thread.
152 *
153 * u4 thread serial number
154 *
155 * HPROF_HEAP_SUMMARY heap summary
156 *
157 * u4 total live bytes
158 * u4 total live instances
159 * u8 total bytes allocated
160 * u8 total instances allocated
161 *
162 * HPROF_HEAP_DUMP denote a heap dump
163 *
164 * [heap dump sub-records]*
165 *
166 * There are four kinds of heap dump sub-records:
167 *
168 * u1 sub-record type
169 *
170 * HPROF_GC_ROOT_UNKNOWN unknown root
171 *
172 * id object ID
173 *
174 * HPROF_GC_ROOT_THREAD_OBJ thread object
175 *
176 * id thread object ID (may be 0 for a
177 * thread newly attached through JNI)
178 * u4 thread sequence number
179 * u4 stack trace sequence number
180 *
181 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root
182 *
183 * id object ID
184 * id JNI global ref ID
185 *
186 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref
187 *
188 * id object ID
189 * u4 thread serial number
190 * u4 frame # in stack trace (-1 for empty)
191 *
192 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame
193 *
194 * id object ID
195 * u4 thread serial number
196 * u4 frame # in stack trace (-1 for empty)
197 *
198 * HPROF_GC_ROOT_NATIVE_STACK Native stack
199 *
200 * id object ID
201 * u4 thread serial number
202 *
203 * HPROF_GC_ROOT_STICKY_CLASS System class
204 *
205 * id object ID
206 *
207 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block
208 *
209 * id object ID
210 * u4 thread serial number
211 *
212 * HPROF_GC_ROOT_MONITOR_USED Busy monitor
213 *
214 * id object ID
215 *
216 * HPROF_GC_CLASS_DUMP dump of a class object
217 *
218 * id class object ID
219 * u4 stack trace serial number
220 * id super class object ID
221 * id class loader object ID
222 * id signers object ID
223 * id protection domain object ID
224 * id reserved
225 * id reserved
226 *
227 * u4 instance size (in bytes)
228 *
229 * u2 size of constant pool
230 * [u2, constant pool index,
231 * ty, type
232 * 2: object
233 * 4: boolean
234 * 5: char
235 * 6: float
236 * 7: double
237 * 8: byte
238 * 9: short
239 * 10: int
240 * 11: long
241 * vl]* and value
242 *
243 * u2 number of static fields
244 * [id, static field name,
245 * ty, type,
246 * vl]* and value
247 *
248 * u2 number of inst. fields (not inc. super)
249 * [id, instance field name,
250 * ty]* type
251 *
252 * HPROF_GC_INSTANCE_DUMP dump of a normal object
253 *
254 * id object ID
255 * u4 stack trace serial number
256 * id class object ID
257 * u4 number of bytes that follow
258 * [vl]* instance field values (class, followed
259 * by super, super's super ...)
260 *
261 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array
262 *
263 * id array object ID
264 * u4 stack trace serial number
265 * u4 number of elements
266 * id array class ID
267 * [id]* elements
268 *
269 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array
270 *
271 * id array object ID
272 * u4 stack trace serial number
273 * u4 number of elements
274 * u1 element type
275 * 4: boolean array
276 * 5: char array
277 * 6: float array
278 * 7: double array
279 * 8: byte array
280 * 9: short array
281 * 10: int array
282 * 11: long array
283 * [u1]* elements
284 *
285 * HPROF_CPU_SAMPLES a set of sample traces of running threads
286 *
287 * u4 total number of samples
288 * u4 # of traces
289 * [u4 # of samples
290 * u4]* stack trace serial number
291 *
292 * HPROF_CONTROL_SETTINGS the settings of on/off switches
293 *
294 * u4 0x00000001: alloc traces on/off
295 * 0x00000002: cpu sampling on/off
296 * u2 stack trace depth
297 *
298 *
299 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
300 * be generated as a sequence of heap dump segments. This sequence is
301 * terminated by an end record. The additional tags allowed by format
302 * "JAVA PROFILE 1.0.2" are:
303 *
304 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
305 *
306 * [heap dump sub-records]*
307 * The same sub-record types allowed by HPROF_HEAP_DUMP
308 *
309 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
310 *
311 */
314 // HPROF tags
316 typedef enum {
317 // top-level records
318 HPROF_UTF8 = 0x01,
319 HPROF_LOAD_CLASS = 0x02,
320 HPROF_UNLOAD_CLASS = 0x03,
321 HPROF_FRAME = 0x04,
322 HPROF_TRACE = 0x05,
323 HPROF_ALLOC_SITES = 0x06,
324 HPROF_HEAP_SUMMARY = 0x07,
325 HPROF_START_THREAD = 0x0A,
326 HPROF_END_THREAD = 0x0B,
327 HPROF_HEAP_DUMP = 0x0C,
328 HPROF_CPU_SAMPLES = 0x0D,
329 HPROF_CONTROL_SETTINGS = 0x0E,
331 // 1.0.2 record types
332 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
333 HPROF_HEAP_DUMP_END = 0x2C,
335 // field types
336 HPROF_ARRAY_OBJECT = 0x01,
337 HPROF_NORMAL_OBJECT = 0x02,
338 HPROF_BOOLEAN = 0x04,
339 HPROF_CHAR = 0x05,
340 HPROF_FLOAT = 0x06,
341 HPROF_DOUBLE = 0x07,
342 HPROF_BYTE = 0x08,
343 HPROF_SHORT = 0x09,
344 HPROF_INT = 0x0A,
345 HPROF_LONG = 0x0B,
347 // data-dump sub-records
348 HPROF_GC_ROOT_UNKNOWN = 0xFF,
349 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
350 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
351 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
352 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
353 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
354 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
355 HPROF_GC_ROOT_MONITOR_USED = 0x07,
356 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
357 HPROF_GC_CLASS_DUMP = 0x20,
358 HPROF_GC_INSTANCE_DUMP = 0x21,
359 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
360 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
361 } hprofTag;
363 // Default stack trace ID (used for dummy HPROF_TRACE record)
364 enum {
365 STACK_TRACE_ID = 1,
366 INITIAL_CLASS_COUNT = 200
367 };
369 // Supports I/O operations on a dump file
371 class DumpWriter : public StackObj {
372 private:
373 enum {
374 io_buffer_size = 8*M
375 };
377 int _fd; // file descriptor (-1 if dump file not open)
378 jlong _bytes_written; // number of byte written to dump file
380 char* _buffer; // internal buffer
381 int _size;
382 int _pos;
384 char* _error; // error message when I/O fails
386 void set_file_descriptor(int fd) { _fd = fd; }
387 int file_descriptor() const { return _fd; }
389 char* buffer() const { return _buffer; }
390 int buffer_size() const { return _size; }
391 int position() const { return _pos; }
392 void set_position(int pos) { _pos = pos; }
394 void set_error(const char* error) { _error = (char*)os::strdup(error); }
396 // all I/O go through this function
397 void write_internal(void* s, int len);
399 public:
400 DumpWriter(const char* path);
401 ~DumpWriter();
403 void close();
404 bool is_open() const { return file_descriptor() >= 0; }
405 void flush();
407 // total number of bytes written to the disk
408 jlong bytes_written() const { return _bytes_written; }
410 // adjust the number of bytes written to disk (used to keep the count
411 // of the number of bytes written in case of rewrites)
412 void adjust_bytes_written(jlong n) { _bytes_written += n; }
414 // number of (buffered) bytes as yet unwritten to the dump file
415 jlong bytes_unwritten() const { return (jlong)position(); }
417 char* error() const { return _error; }
419 jlong current_offset();
420 void seek_to_offset(jlong pos);
422 // writer functions
423 void write_raw(void* s, int len);
424 void write_u1(u1 x) { write_raw((void*)&x, 1); }
425 void write_u2(u2 x);
426 void write_u4(u4 x);
427 void write_u8(u8 x);
428 void write_objectID(oop o);
429 void write_symbolID(Symbol* o);
430 void write_classID(Klass* k);
431 void write_id(u4 x);
432 };
434 DumpWriter::DumpWriter(const char* path) {
435 // try to allocate an I/O buffer of io_buffer_size. If there isn't
436 // sufficient memory then reduce size until we can allocate something.
437 _size = io_buffer_size;
438 do {
439 _buffer = (char*)os::malloc(_size, mtInternal);
440 if (_buffer == NULL) {
441 _size = _size >> 1;
442 }
443 } while (_buffer == NULL && _size > 0);
444 assert((_size > 0 && _buffer != NULL) || (_size == 0 && _buffer == NULL), "sanity check");
445 _pos = 0;
446 _error = NULL;
447 _bytes_written = 0L;
448 _fd = os::create_binary_file(path, false); // don't replace existing file
450 // if the open failed we record the error
451 if (_fd < 0) {
452 _error = (char*)os::strdup(strerror(errno));
453 }
454 }
456 DumpWriter::~DumpWriter() {
457 // flush and close dump file
458 if (is_open()) {
459 close();
460 }
461 if (_buffer != NULL) os::free(_buffer);
462 if (_error != NULL) os::free(_error);
463 }
465 // closes dump file (if open)
466 void DumpWriter::close() {
467 // flush and close dump file
468 if (is_open()) {
469 flush();
470 ::close(file_descriptor());
471 set_file_descriptor(-1);
472 }
473 }
475 // write directly to the file
476 void DumpWriter::write_internal(void* s, int len) {
477 if (is_open()) {
478 int n = ::write(file_descriptor(), s, len);
479 if (n > 0) {
480 _bytes_written += n;
481 }
482 if (n != len) {
483 if (n < 0) {
484 set_error(strerror(errno));
485 } else {
486 set_error("file size limit");
487 }
488 ::close(file_descriptor());
489 set_file_descriptor(-1);
490 }
491 }
492 }
494 // write raw bytes
495 void DumpWriter::write_raw(void* s, int len) {
496 if (is_open()) {
497 // flush buffer to make toom
498 if ((position()+ len) >= buffer_size()) {
499 flush();
500 }
502 // buffer not available or too big to buffer it
503 if ((buffer() == NULL) || (len >= buffer_size())) {
504 write_internal(s, len);
505 } else {
506 // Should optimize this for u1/u2/u4/u8 sizes.
507 memcpy(buffer() + position(), s, len);
508 set_position(position() + len);
509 }
510 }
511 }
513 // flush any buffered bytes to the file
514 void DumpWriter::flush() {
515 if (is_open() && position() > 0) {
516 write_internal(buffer(), position());
517 set_position(0);
518 }
519 }
522 jlong DumpWriter::current_offset() {
523 if (is_open()) {
524 // the offset is the file offset plus whatever we have buffered
525 jlong offset = os::current_file_offset(file_descriptor());
526 assert(offset >= 0, "lseek failed");
527 return offset + (jlong)position();
528 } else {
529 return (jlong)-1;
530 }
531 }
533 void DumpWriter::seek_to_offset(jlong off) {
534 assert(off >= 0, "bad offset");
536 // need to flush before seeking
537 flush();
539 // may be closed due to I/O error
540 if (is_open()) {
541 jlong n = os::seek_to_file_offset(file_descriptor(), off);
542 assert(n >= 0, "lseek failed");
543 }
544 }
546 void DumpWriter::write_u2(u2 x) {
547 u2 v;
548 Bytes::put_Java_u2((address)&v, x);
549 write_raw((void*)&v, 2);
550 }
552 void DumpWriter::write_u4(u4 x) {
553 u4 v;
554 Bytes::put_Java_u4((address)&v, x);
555 write_raw((void*)&v, 4);
556 }
558 void DumpWriter::write_u8(u8 x) {
559 u8 v;
560 Bytes::put_Java_u8((address)&v, x);
561 write_raw((void*)&v, 8);
562 }
564 void DumpWriter::write_objectID(oop o) {
565 address a = (address)((uintptr_t)o);
566 #ifdef _LP64
567 write_u8((u8)a);
568 #else
569 write_u4((u4)a);
570 #endif
571 }
573 void DumpWriter::write_symbolID(Symbol* s) {
574 address a = (address)((uintptr_t)s);
575 #ifdef _LP64
576 write_u8((u8)a);
577 #else
578 write_u4((u4)a);
579 #endif
580 }
582 void DumpWriter::write_id(u4 x) {
583 #ifdef _LP64
584 write_u8((u8) x);
585 #else
586 write_u4(x);
587 #endif
588 }
590 // We use java mirror as the class ID
591 void DumpWriter::write_classID(Klass* k) {
592 write_objectID(k->java_mirror());
593 }
597 // Support class with a collection of functions used when dumping the heap
599 class DumperSupport : AllStatic {
600 public:
602 // write a header of the given type
603 static void write_header(DumpWriter* writer, hprofTag tag, u4 len);
605 // returns hprof tag for the given type signature
606 static hprofTag sig2tag(Symbol* sig);
607 // returns hprof tag for the given basic type
608 static hprofTag type2tag(BasicType type);
610 // returns the size of the instance of the given class
611 static u4 instance_size(Klass* k);
613 // dump a jfloat
614 static void dump_float(DumpWriter* writer, jfloat f);
615 // dump a jdouble
616 static void dump_double(DumpWriter* writer, jdouble d);
617 // dumps the raw value of the given field
618 static void dump_field_value(DumpWriter* writer, char type, address addr);
619 // dumps static fields of the given class
620 static void dump_static_fields(DumpWriter* writer, Klass* k);
621 // dump the raw values of the instance fields of the given object
622 static void dump_instance_fields(DumpWriter* writer, oop o);
623 // dumps the definition of the instance fields for a given class
624 static void dump_instance_field_descriptors(DumpWriter* writer, Klass* k);
625 // creates HPROF_GC_INSTANCE_DUMP record for the given object
626 static void dump_instance(DumpWriter* writer, oop o);
627 // creates HPROF_GC_CLASS_DUMP record for the given class and each of its
628 // array classes
629 static void dump_class_and_array_classes(DumpWriter* writer, Klass* k);
630 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
631 // class (and each multi-dimensional array class too)
632 static void dump_basic_type_array_class(DumpWriter* writer, Klass* k);
634 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
635 static void dump_object_array(DumpWriter* writer, objArrayOop array);
636 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
637 static void dump_prim_array(DumpWriter* writer, typeArrayOop array);
638 // create HPROF_FRAME record for the given method and bci
639 static void dump_stack_frame(DumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
640 };
642 // write a header of the given type
643 void DumperSupport:: write_header(DumpWriter* writer, hprofTag tag, u4 len) {
644 writer->write_u1((u1)tag);
645 writer->write_u4(0); // current ticks
646 writer->write_u4(len);
647 }
649 // returns hprof tag for the given type signature
650 hprofTag DumperSupport::sig2tag(Symbol* sig) {
651 switch (sig->byte_at(0)) {
652 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT;
653 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT;
654 case JVM_SIGNATURE_BYTE : return HPROF_BYTE;
655 case JVM_SIGNATURE_CHAR : return HPROF_CHAR;
656 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT;
657 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE;
658 case JVM_SIGNATURE_INT : return HPROF_INT;
659 case JVM_SIGNATURE_LONG : return HPROF_LONG;
660 case JVM_SIGNATURE_SHORT : return HPROF_SHORT;
661 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN;
662 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
663 }
664 }
666 hprofTag DumperSupport::type2tag(BasicType type) {
667 switch (type) {
668 case T_BYTE : return HPROF_BYTE;
669 case T_CHAR : return HPROF_CHAR;
670 case T_FLOAT : return HPROF_FLOAT;
671 case T_DOUBLE : return HPROF_DOUBLE;
672 case T_INT : return HPROF_INT;
673 case T_LONG : return HPROF_LONG;
674 case T_SHORT : return HPROF_SHORT;
675 case T_BOOLEAN : return HPROF_BOOLEAN;
676 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
677 }
678 }
680 // dump a jfloat
681 void DumperSupport::dump_float(DumpWriter* writer, jfloat f) {
682 if (g_isnan(f)) {
683 writer->write_u4(0x7fc00000); // collapsing NaNs
684 } else {
685 union {
686 int i;
687 float f;
688 } u;
689 u.f = (float)f;
690 writer->write_u4((u4)u.i);
691 }
692 }
694 // dump a jdouble
695 void DumperSupport::dump_double(DumpWriter* writer, jdouble d) {
696 union {
697 jlong l;
698 double d;
699 } u;
700 if (g_isnan(d)) { // collapsing NaNs
701 u.l = (jlong)(0x7ff80000);
702 u.l = (u.l << 32);
703 } else {
704 u.d = (double)d;
705 }
706 writer->write_u8((u8)u.l);
707 }
709 // dumps the raw value of the given field
710 void DumperSupport::dump_field_value(DumpWriter* writer, char type, address addr) {
711 switch (type) {
712 case JVM_SIGNATURE_CLASS :
713 case JVM_SIGNATURE_ARRAY : {
714 oop o;
715 if (UseCompressedOops) {
716 o = oopDesc::load_decode_heap_oop((narrowOop*)addr);
717 } else {
718 o = oopDesc::load_decode_heap_oop((oop*)addr);
719 }
721 // reflection and sun.misc.Unsafe classes may have a reference to a
722 // Klass* so filter it out.
723 assert(o->is_oop_or_null(), "should always be an oop");
724 writer->write_objectID(o);
725 break;
726 }
727 case JVM_SIGNATURE_BYTE : {
728 jbyte* b = (jbyte*)addr;
729 writer->write_u1((u1)*b);
730 break;
731 }
732 case JVM_SIGNATURE_CHAR : {
733 jchar* c = (jchar*)addr;
734 writer->write_u2((u2)*c);
735 break;
736 }
737 case JVM_SIGNATURE_SHORT : {
738 jshort* s = (jshort*)addr;
739 writer->write_u2((u2)*s);
740 break;
741 }
742 case JVM_SIGNATURE_FLOAT : {
743 jfloat* f = (jfloat*)addr;
744 dump_float(writer, *f);
745 break;
746 }
747 case JVM_SIGNATURE_DOUBLE : {
748 jdouble* f = (jdouble*)addr;
749 dump_double(writer, *f);
750 break;
751 }
752 case JVM_SIGNATURE_INT : {
753 jint* i = (jint*)addr;
754 writer->write_u4((u4)*i);
755 break;
756 }
757 case JVM_SIGNATURE_LONG : {
758 jlong* l = (jlong*)addr;
759 writer->write_u8((u8)*l);
760 break;
761 }
762 case JVM_SIGNATURE_BOOLEAN : {
763 jboolean* b = (jboolean*)addr;
764 writer->write_u1((u1)*b);
765 break;
766 }
767 default : ShouldNotReachHere();
768 }
769 }
771 // returns the size of the instance of the given class
772 u4 DumperSupport::instance_size(Klass* k) {
773 HandleMark hm;
774 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
776 int size = 0;
778 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
779 if (!fld.access_flags().is_static()) {
780 Symbol* sig = fld.signature();
781 switch (sig->byte_at(0)) {
782 case JVM_SIGNATURE_CLASS :
783 case JVM_SIGNATURE_ARRAY : size += oopSize; break;
785 case JVM_SIGNATURE_BYTE :
786 case JVM_SIGNATURE_BOOLEAN : size += 1; break;
788 case JVM_SIGNATURE_CHAR :
789 case JVM_SIGNATURE_SHORT : size += 2; break;
791 case JVM_SIGNATURE_INT :
792 case JVM_SIGNATURE_FLOAT : size += 4; break;
794 case JVM_SIGNATURE_LONG :
795 case JVM_SIGNATURE_DOUBLE : size += 8; break;
797 default : ShouldNotReachHere();
798 }
799 }
800 }
801 return (u4)size;
802 }
804 // dumps static fields of the given class
805 void DumperSupport::dump_static_fields(DumpWriter* writer, Klass* k) {
806 HandleMark hm;
807 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
809 // pass 1 - count the static fields
810 u2 field_count = 0;
811 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
812 if (fldc.access_flags().is_static()) field_count++;
813 }
815 writer->write_u2(field_count);
817 // pass 2 - dump the field descriptors and raw values
818 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
819 if (fld.access_flags().is_static()) {
820 Symbol* sig = fld.signature();
822 writer->write_symbolID(fld.name()); // name
823 writer->write_u1(sig2tag(sig)); // type
825 // value
826 int offset = fld.offset();
827 address addr = (address)ikh->java_mirror() + offset;
829 dump_field_value(writer, sig->byte_at(0), addr);
830 }
831 }
832 }
834 // dump the raw values of the instance fields of the given object
835 void DumperSupport::dump_instance_fields(DumpWriter* writer, oop o) {
836 HandleMark hm;
837 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), o->klass());
839 for (FieldStream fld(ikh, false, false); !fld.eos(); fld.next()) {
840 if (!fld.access_flags().is_static()) {
841 Symbol* sig = fld.signature();
842 address addr = (address)o + fld.offset();
844 dump_field_value(writer, sig->byte_at(0), addr);
845 }
846 }
847 }
849 // dumps the definition of the instance fields for a given class
850 void DumperSupport::dump_instance_field_descriptors(DumpWriter* writer, Klass* k) {
851 HandleMark hm;
852 instanceKlassHandle ikh = instanceKlassHandle(Thread::current(), k);
854 // pass 1 - count the instance fields
855 u2 field_count = 0;
856 for (FieldStream fldc(ikh, true, true); !fldc.eos(); fldc.next()) {
857 if (!fldc.access_flags().is_static()) field_count++;
858 }
860 writer->write_u2(field_count);
862 // pass 2 - dump the field descriptors
863 for (FieldStream fld(ikh, true, true); !fld.eos(); fld.next()) {
864 if (!fld.access_flags().is_static()) {
865 Symbol* sig = fld.signature();
867 writer->write_symbolID(fld.name()); // name
868 writer->write_u1(sig2tag(sig)); // type
869 }
870 }
871 }
873 // creates HPROF_GC_INSTANCE_DUMP record for the given object
874 void DumperSupport::dump_instance(DumpWriter* writer, oop o) {
875 Klass* k = o->klass();
877 writer->write_u1(HPROF_GC_INSTANCE_DUMP);
878 writer->write_objectID(o);
879 writer->write_u4(STACK_TRACE_ID);
881 // class ID
882 writer->write_classID(k);
884 // number of bytes that follow
885 writer->write_u4(instance_size(k) );
887 // field values
888 dump_instance_fields(writer, o);
889 }
891 // creates HPROF_GC_CLASS_DUMP record for the given class and each of
892 // its array classes
893 void DumperSupport::dump_class_and_array_classes(DumpWriter* writer, Klass* k) {
894 Klass* klass = k;
895 assert(klass->oop_is_instance(), "not an InstanceKlass");
896 InstanceKlass* ik = (InstanceKlass*)klass;
898 writer->write_u1(HPROF_GC_CLASS_DUMP);
900 // class ID
901 writer->write_classID(ik);
902 writer->write_u4(STACK_TRACE_ID);
904 // super class ID
905 Klass* java_super = ik->java_super();
906 if (java_super == NULL) {
907 writer->write_objectID(oop(NULL));
908 } else {
909 writer->write_classID(java_super);
910 }
912 writer->write_objectID(ik->class_loader());
913 writer->write_objectID(ik->signers());
914 writer->write_objectID(ik->protection_domain());
916 // reserved
917 writer->write_objectID(oop(NULL));
918 writer->write_objectID(oop(NULL));
920 // instance size
921 writer->write_u4(DumperSupport::instance_size(k));
923 // size of constant pool - ignored by HAT 1.1
924 writer->write_u2(0);
926 // number of static fields
927 dump_static_fields(writer, k);
929 // description of instance fields
930 dump_instance_field_descriptors(writer, k);
932 // array classes
933 k = klass->array_klass_or_null();
934 while (k != NULL) {
935 Klass* klass = k;
936 assert(klass->oop_is_objArray(), "not an ObjArrayKlass");
938 writer->write_u1(HPROF_GC_CLASS_DUMP);
939 writer->write_classID(klass);
940 writer->write_u4(STACK_TRACE_ID);
942 // super class of array classes is java.lang.Object
943 java_super = klass->java_super();
944 assert(java_super != NULL, "checking");
945 writer->write_classID(java_super);
947 writer->write_objectID(ik->class_loader());
948 writer->write_objectID(ik->signers());
949 writer->write_objectID(ik->protection_domain());
951 writer->write_objectID(oop(NULL)); // reserved
952 writer->write_objectID(oop(NULL));
953 writer->write_u4(0); // instance size
954 writer->write_u2(0); // constant pool
955 writer->write_u2(0); // static fields
956 writer->write_u2(0); // instance fields
958 // get the array class for the next rank
959 k = klass->array_klass_or_null();
960 }
961 }
963 // creates HPROF_GC_CLASS_DUMP record for a given primitive array
964 // class (and each multi-dimensional array class too)
965 void DumperSupport::dump_basic_type_array_class(DumpWriter* writer, Klass* k) {
966 // array classes
967 while (k != NULL) {
968 Klass* klass = k;
970 writer->write_u1(HPROF_GC_CLASS_DUMP);
971 writer->write_classID(klass);
972 writer->write_u4(STACK_TRACE_ID);
974 // super class of array classes is java.lang.Object
975 Klass* java_super = klass->java_super();
976 assert(java_super != NULL, "checking");
977 writer->write_classID(java_super);
979 writer->write_objectID(oop(NULL)); // loader
980 writer->write_objectID(oop(NULL)); // signers
981 writer->write_objectID(oop(NULL)); // protection domain
983 writer->write_objectID(oop(NULL)); // reserved
984 writer->write_objectID(oop(NULL));
985 writer->write_u4(0); // instance size
986 writer->write_u2(0); // constant pool
987 writer->write_u2(0); // static fields
988 writer->write_u2(0); // instance fields
990 // get the array class for the next rank
991 k = klass->array_klass_or_null();
992 }
993 }
995 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
996 void DumperSupport::dump_object_array(DumpWriter* writer, objArrayOop array) {
998 writer->write_u1(HPROF_GC_OBJ_ARRAY_DUMP);
999 writer->write_objectID(array);
1000 writer->write_u4(STACK_TRACE_ID);
1001 writer->write_u4((u4)array->length());
1003 // array class ID
1004 writer->write_classID(array->klass());
1006 // [id]* elements
1007 for (int index=0; index<array->length(); index++) {
1008 oop o = array->obj_at(index);
1009 writer->write_objectID(o);
1010 }
1011 }
1013 #define WRITE_ARRAY(Array, Type, Size) \
1014 for (int i=0; i<Array->length(); i++) { writer->write_##Size((Size)array->Type##_at(i)); }
1017 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1018 void DumperSupport::dump_prim_array(DumpWriter* writer, typeArrayOop array) {
1019 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1021 writer->write_u1(HPROF_GC_PRIM_ARRAY_DUMP);
1022 writer->write_objectID(array);
1023 writer->write_u4(STACK_TRACE_ID);
1024 writer->write_u4((u4)array->length());
1025 writer->write_u1(type2tag(type));
1027 // nothing to copy
1028 if (array->length() == 0) {
1029 return;
1030 }
1032 // If the byte ordering is big endian then we can copy most types directly
1033 int length_in_bytes = array->length() * type2aelembytes(type);
1034 assert(length_in_bytes > 0, "nothing to copy");
1036 switch (type) {
1037 case T_INT : {
1038 if (Bytes::is_Java_byte_ordering_different()) {
1039 WRITE_ARRAY(array, int, u4);
1040 } else {
1041 writer->write_raw((void*)(array->int_at_addr(0)), length_in_bytes);
1042 }
1043 break;
1044 }
1045 case T_BYTE : {
1046 writer->write_raw((void*)(array->byte_at_addr(0)), length_in_bytes);
1047 break;
1048 }
1049 case T_CHAR : {
1050 if (Bytes::is_Java_byte_ordering_different()) {
1051 WRITE_ARRAY(array, char, u2);
1052 } else {
1053 writer->write_raw((void*)(array->char_at_addr(0)), length_in_bytes);
1054 }
1055 break;
1056 }
1057 case T_SHORT : {
1058 if (Bytes::is_Java_byte_ordering_different()) {
1059 WRITE_ARRAY(array, short, u2);
1060 } else {
1061 writer->write_raw((void*)(array->short_at_addr(0)), length_in_bytes);
1062 }
1063 break;
1064 }
1065 case T_BOOLEAN : {
1066 if (Bytes::is_Java_byte_ordering_different()) {
1067 WRITE_ARRAY(array, bool, u1);
1068 } else {
1069 writer->write_raw((void*)(array->bool_at_addr(0)), length_in_bytes);
1070 }
1071 break;
1072 }
1073 case T_LONG : {
1074 if (Bytes::is_Java_byte_ordering_different()) {
1075 WRITE_ARRAY(array, long, u8);
1076 } else {
1077 writer->write_raw((void*)(array->long_at_addr(0)), length_in_bytes);
1078 }
1079 break;
1080 }
1082 // handle float/doubles in a special value to ensure than NaNs are
1083 // written correctly. TO DO: Check if we can avoid this on processors that
1084 // use IEEE 754.
1086 case T_FLOAT : {
1087 for (int i=0; i<array->length(); i++) {
1088 dump_float( writer, array->float_at(i) );
1089 }
1090 break;
1091 }
1092 case T_DOUBLE : {
1093 for (int i=0; i<array->length(); i++) {
1094 dump_double( writer, array->double_at(i) );
1095 }
1096 break;
1097 }
1098 default : ShouldNotReachHere();
1099 }
1100 }
1102 // create a HPROF_FRAME record of the given Method* and bci
1103 void DumperSupport::dump_stack_frame(DumpWriter* writer,
1104 int frame_serial_num,
1105 int class_serial_num,
1106 Method* m,
1107 int bci) {
1108 int line_number;
1109 if (m->is_native()) {
1110 line_number = -3; // native frame
1111 } else {
1112 line_number = m->line_number_from_bci(bci);
1113 }
1115 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1116 writer->write_id(frame_serial_num); // frame serial number
1117 writer->write_symbolID(m->name()); // method's name
1118 writer->write_symbolID(m->signature()); // method's signature
1120 assert(m->method_holder()->oop_is_instance(), "not InstanceKlass");
1121 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1122 writer->write_u4(class_serial_num); // class serial number
1123 writer->write_u4((u4) line_number); // line number
1124 }
1127 // Support class used to generate HPROF_UTF8 records from the entries in the
1128 // SymbolTable.
1130 class SymbolTableDumper : public SymbolClosure {
1131 private:
1132 DumpWriter* _writer;
1133 DumpWriter* writer() const { return _writer; }
1134 public:
1135 SymbolTableDumper(DumpWriter* writer) { _writer = writer; }
1136 void do_symbol(Symbol** p);
1137 };
1139 void SymbolTableDumper::do_symbol(Symbol** p) {
1140 ResourceMark rm;
1141 Symbol* sym = load_symbol(p);
1142 int len = sym->utf8_length();
1143 if (len > 0) {
1144 char* s = sym->as_utf8();
1145 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
1146 writer()->write_symbolID(sym);
1147 writer()->write_raw(s, len);
1148 }
1149 }
1151 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
1153 class JNILocalsDumper : public OopClosure {
1154 private:
1155 DumpWriter* _writer;
1156 u4 _thread_serial_num;
1157 int _frame_num;
1158 DumpWriter* writer() const { return _writer; }
1159 public:
1160 JNILocalsDumper(DumpWriter* writer, u4 thread_serial_num) {
1161 _writer = writer;
1162 _thread_serial_num = thread_serial_num;
1163 _frame_num = -1; // default - empty stack
1164 }
1165 void set_frame_number(int n) { _frame_num = n; }
1166 void do_oop(oop* obj_p);
1167 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1168 };
1171 void JNILocalsDumper::do_oop(oop* obj_p) {
1172 // ignore null or deleted handles
1173 oop o = *obj_p;
1174 if (o != NULL && o != JNIHandles::deleted_handle()) {
1175 writer()->write_u1(HPROF_GC_ROOT_JNI_LOCAL);
1176 writer()->write_objectID(o);
1177 writer()->write_u4(_thread_serial_num);
1178 writer()->write_u4((u4)_frame_num);
1179 }
1180 }
1183 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
1185 class JNIGlobalsDumper : public OopClosure {
1186 private:
1187 DumpWriter* _writer;
1188 DumpWriter* writer() const { return _writer; }
1190 public:
1191 JNIGlobalsDumper(DumpWriter* writer) {
1192 _writer = writer;
1193 }
1194 void do_oop(oop* obj_p);
1195 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1196 };
1198 void JNIGlobalsDumper::do_oop(oop* obj_p) {
1199 oop o = *obj_p;
1201 // ignore these
1202 if (o == NULL || o == JNIHandles::deleted_handle()) return;
1204 // we ignore global ref to symbols and other internal objects
1205 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) {
1206 writer()->write_u1(HPROF_GC_ROOT_JNI_GLOBAL);
1207 writer()->write_objectID(o);
1208 writer()->write_objectID((oopDesc*)obj_p); // global ref ID
1209 }
1210 };
1213 // Support class used to generate HPROF_GC_ROOT_MONITOR_USED records
1215 class MonitorUsedDumper : public OopClosure {
1216 private:
1217 DumpWriter* _writer;
1218 DumpWriter* writer() const { return _writer; }
1219 public:
1220 MonitorUsedDumper(DumpWriter* writer) {
1221 _writer = writer;
1222 }
1223 void do_oop(oop* obj_p) {
1224 writer()->write_u1(HPROF_GC_ROOT_MONITOR_USED);
1225 writer()->write_objectID(*obj_p);
1226 }
1227 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
1228 };
1231 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
1233 class StickyClassDumper : public KlassClosure {
1234 private:
1235 DumpWriter* _writer;
1236 DumpWriter* writer() const { return _writer; }
1237 public:
1238 StickyClassDumper(DumpWriter* writer) {
1239 _writer = writer;
1240 }
1241 void do_klass(Klass* k) {
1242 if (k->oop_is_instance()) {
1243 InstanceKlass* ik = InstanceKlass::cast(k);
1244 writer()->write_u1(HPROF_GC_ROOT_STICKY_CLASS);
1245 writer()->write_classID(ik);
1246 }
1247 }
1248 };
1251 class VM_HeapDumper;
1253 // Support class using when iterating over the heap.
1255 class HeapObjectDumper : public ObjectClosure {
1256 private:
1257 VM_HeapDumper* _dumper;
1258 DumpWriter* _writer;
1260 VM_HeapDumper* dumper() { return _dumper; }
1261 DumpWriter* writer() { return _writer; }
1263 // used to indicate that a record has been writen
1264 void mark_end_of_record();
1266 public:
1267 HeapObjectDumper(VM_HeapDumper* dumper, DumpWriter* writer) {
1268 _dumper = dumper;
1269 _writer = writer;
1270 }
1272 // called for each object in the heap
1273 void do_object(oop o);
1274 };
1276 void HeapObjectDumper::do_object(oop o) {
1277 // hide the sentinel for deleted handles
1278 if (o == JNIHandles::deleted_handle()) return;
1280 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records
1281 if (o->klass() == SystemDictionary::Class_klass()) {
1282 if (!java_lang_Class::is_primitive(o)) {
1283 return;
1284 }
1285 }
1287 // create a HPROF_GC_INSTANCE record for each object
1288 if (o->is_instance()) {
1289 DumperSupport::dump_instance(writer(), o);
1290 mark_end_of_record();
1291 } else {
1292 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
1293 if (o->is_objArray()) {
1294 DumperSupport::dump_object_array(writer(), objArrayOop(o));
1295 mark_end_of_record();
1296 } else {
1297 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
1298 if (o->is_typeArray()) {
1299 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
1300 mark_end_of_record();
1301 }
1302 }
1303 }
1304 }
1306 // The VM operation that performs the heap dump
1307 class VM_HeapDumper : public VM_GC_Operation {
1308 private:
1309 static VM_HeapDumper* _global_dumper;
1310 static DumpWriter* _global_writer;
1311 DumpWriter* _local_writer;
1312 JavaThread* _oome_thread;
1313 Method* _oome_constructor;
1314 bool _gc_before_heap_dump;
1315 bool _is_segmented_dump;
1316 jlong _dump_start;
1317 GrowableArray<Klass*>* _klass_map;
1318 ThreadStackTrace** _stack_traces;
1319 int _num_threads;
1321 // accessors and setters
1322 static VM_HeapDumper* dumper() { assert(_global_dumper != NULL, "Error"); return _global_dumper; }
1323 static DumpWriter* writer() { assert(_global_writer != NULL, "Error"); return _global_writer; }
1324 void set_global_dumper() {
1325 assert(_global_dumper == NULL, "Error");
1326 _global_dumper = this;
1327 }
1328 void set_global_writer() {
1329 assert(_global_writer == NULL, "Error");
1330 _global_writer = _local_writer;
1331 }
1332 void clear_global_dumper() { _global_dumper = NULL; }
1333 void clear_global_writer() { _global_writer = NULL; }
1335 bool is_segmented_dump() const { return _is_segmented_dump; }
1336 void set_segmented_dump() { _is_segmented_dump = true; }
1337 jlong dump_start() const { return _dump_start; }
1338 void set_dump_start(jlong pos);
1340 bool skip_operation() const;
1342 // writes a HPROF_LOAD_CLASS record
1343 static void do_load_class(Klass* k);
1345 // writes a HPROF_GC_CLASS_DUMP record for the given class
1346 // (and each array class too)
1347 static void do_class_dump(Klass* k);
1349 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1350 // array (and each multi-dimensional array too)
1351 static void do_basic_type_array_class_dump(Klass* k);
1353 // HPROF_GC_ROOT_THREAD_OBJ records
1354 int do_thread(JavaThread* thread, u4 thread_serial_num);
1355 void do_threads();
1357 void add_class_serial_number(Klass* k, int serial_num) {
1358 _klass_map->at_put_grow(serial_num, k);
1359 }
1361 // HPROF_TRACE and HPROF_FRAME records
1362 void dump_stack_traces();
1364 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record
1365 void write_dump_header();
1367 // fixes up the length of the current dump record
1368 void write_current_dump_record_length();
1370 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END
1371 // record in the case of a segmented heap dump)
1372 void end_of_dump();
1374 public:
1375 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome) :
1376 VM_GC_Operation(0 /* total collections, dummy, ignored */,
1377 GCCause::_heap_dump /* GC Cause */,
1378 0 /* total full collections, dummy, ignored */,
1379 gc_before_heap_dump) {
1380 _local_writer = writer;
1381 _gc_before_heap_dump = gc_before_heap_dump;
1382 _is_segmented_dump = false;
1383 _dump_start = (jlong)-1;
1384 _klass_map = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, true);
1385 _stack_traces = NULL;
1386 _num_threads = 0;
1387 if (oome) {
1388 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread");
1389 // get OutOfMemoryError zero-parameter constructor
1390 InstanceKlass* oome_ik = InstanceKlass::cast(SystemDictionary::OutOfMemoryError_klass());
1391 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(),
1392 vmSymbols::void_method_signature());
1393 // get thread throwing OOME when generating the heap dump at OOME
1394 _oome_thread = JavaThread::current();
1395 } else {
1396 _oome_thread = NULL;
1397 _oome_constructor = NULL;
1398 }
1399 }
1400 ~VM_HeapDumper() {
1401 if (_stack_traces != NULL) {
1402 for (int i=0; i < _num_threads; i++) {
1403 delete _stack_traces[i];
1404 }
1405 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces, mtInternal);
1406 }
1407 delete _klass_map;
1408 }
1410 VMOp_Type type() const { return VMOp_HeapDumper; }
1411 // used to mark sub-record boundary
1412 void check_segment_length();
1413 void doit();
1414 };
1416 VM_HeapDumper* VM_HeapDumper::_global_dumper = NULL;
1417 DumpWriter* VM_HeapDumper::_global_writer = NULL;
1419 bool VM_HeapDumper::skip_operation() const {
1420 return false;
1421 }
1423 // sets the dump starting position
1424 void VM_HeapDumper::set_dump_start(jlong pos) {
1425 _dump_start = pos;
1426 }
1428 // writes a HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT record
1429 void VM_HeapDumper::write_dump_header() {
1430 if (writer()->is_open()) {
1431 if (is_segmented_dump()) {
1432 writer()->write_u1(HPROF_HEAP_DUMP_SEGMENT);
1433 } else {
1434 writer()->write_u1(HPROF_HEAP_DUMP);
1435 }
1436 writer()->write_u4(0); // current ticks
1438 // record the starting position for the dump (its length will be fixed up later)
1439 set_dump_start(writer()->current_offset());
1440 writer()->write_u4(0);
1441 }
1442 }
1444 // fixes up the length of the current dump record
1445 void VM_HeapDumper::write_current_dump_record_length() {
1446 if (writer()->is_open()) {
1447 assert(dump_start() >= 0, "no dump start recorded");
1449 // calculate the size of the dump record
1450 jlong dump_end = writer()->current_offset();
1451 jlong dump_len = (dump_end - dump_start() - 4);
1453 // record length must fit in a u4
1454 if (dump_len > (jlong)(4L*(jlong)G)) {
1455 warning("record is too large");
1456 }
1458 // seek to the dump start and fix-up the length
1459 writer()->seek_to_offset(dump_start());
1460 writer()->write_u4((u4)dump_len);
1462 // adjust the total size written to keep the bytes written correct.
1463 writer()->adjust_bytes_written(-((long) sizeof(u4)));
1465 // seek to dump end so we can continue
1466 writer()->seek_to_offset(dump_end);
1468 // no current dump record
1469 set_dump_start((jlong)-1);
1470 }
1471 }
1473 // used on a sub-record boundary to check if we need to start a
1474 // new segment.
1475 void VM_HeapDumper::check_segment_length() {
1476 if (writer()->is_open()) {
1477 if (is_segmented_dump()) {
1478 // don't use current_offset that would be too expensive on a per record basis
1479 jlong dump_end = writer()->bytes_written() + writer()->bytes_unwritten();
1480 assert(dump_end == writer()->current_offset(), "checking");
1481 jlong dump_len = (dump_end - dump_start() - 4);
1482 assert(dump_len >= 0 && dump_len <= max_juint, "bad dump length");
1484 if (dump_len > (jlong)HeapDumpSegmentSize) {
1485 write_current_dump_record_length();
1486 write_dump_header();
1487 }
1488 }
1489 }
1490 }
1492 // fixes up the current dump record )and writes HPROF_HEAP_DUMP_END
1493 // record in the case of a segmented heap dump)
1494 void VM_HeapDumper::end_of_dump() {
1495 if (writer()->is_open()) {
1496 write_current_dump_record_length();
1498 // for segmented dump we write the end record
1499 if (is_segmented_dump()) {
1500 writer()->write_u1(HPROF_HEAP_DUMP_END);
1501 writer()->write_u4(0);
1502 writer()->write_u4(0);
1503 }
1504 }
1505 }
1507 // marks sub-record boundary
1508 void HeapObjectDumper::mark_end_of_record() {
1509 dumper()->check_segment_length();
1510 }
1512 // writes a HPROF_LOAD_CLASS record for the class (and each of its
1513 // array classes)
1514 void VM_HeapDumper::do_load_class(Klass* k) {
1515 static u4 class_serial_num = 0;
1517 // len of HPROF_LOAD_CLASS record
1518 u4 remaining = 2*oopSize + 2*sizeof(u4);
1520 // write a HPROF_LOAD_CLASS for the class and each array class
1521 do {
1522 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
1524 // class serial number is just a number
1525 writer()->write_u4(++class_serial_num);
1527 // class ID
1528 Klass* klass = k;
1529 writer()->write_classID(klass);
1531 // add the Klass* and class serial number pair
1532 dumper()->add_class_serial_number(klass, class_serial_num);
1534 writer()->write_u4(STACK_TRACE_ID);
1536 // class name ID
1537 Symbol* name = klass->name();
1538 writer()->write_symbolID(name);
1540 // write a LOAD_CLASS record for the array type (if it exists)
1541 k = klass->array_klass_or_null();
1542 } while (k != NULL);
1543 }
1545 // writes a HPROF_GC_CLASS_DUMP record for the given class
1546 void VM_HeapDumper::do_class_dump(Klass* k) {
1547 DumperSupport::dump_class_and_array_classes(writer(), k);
1548 }
1550 // writes a HPROF_GC_CLASS_DUMP records for a given basic type
1551 // array (and each multi-dimensional array too)
1552 void VM_HeapDumper::do_basic_type_array_class_dump(Klass* k) {
1553 DumperSupport::dump_basic_type_array_class(writer(), k);
1554 }
1556 // Walk the stack of the given thread.
1557 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local
1558 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local
1559 //
1560 // It returns the number of Java frames in this thread stack
1561 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) {
1562 JNILocalsDumper blk(writer(), thread_serial_num);
1564 oop threadObj = java_thread->threadObj();
1565 assert(threadObj != NULL, "sanity check");
1567 int stack_depth = 0;
1568 if (java_thread->has_last_Java_frame()) {
1570 // vframes are resource allocated
1571 Thread* current_thread = Thread::current();
1572 ResourceMark rm(current_thread);
1573 HandleMark hm(current_thread);
1575 RegisterMap reg_map(java_thread);
1576 frame f = java_thread->last_frame();
1577 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread);
1578 frame* last_entry_frame = NULL;
1579 int extra_frames = 0;
1581 if (java_thread == _oome_thread && _oome_constructor != NULL) {
1582 extra_frames++;
1583 }
1584 while (vf != NULL) {
1585 blk.set_frame_number(stack_depth);
1586 if (vf->is_java_frame()) {
1588 // java frame (interpreted, compiled, ...)
1589 javaVFrame *jvf = javaVFrame::cast(vf);
1590 if (!(jvf->method()->is_native())) {
1591 StackValueCollection* locals = jvf->locals();
1592 for (int slot=0; slot<locals->size(); slot++) {
1593 if (locals->at(slot)->type() == T_OBJECT) {
1594 oop o = locals->obj_at(slot)();
1596 if (o != NULL) {
1597 writer()->write_u1(HPROF_GC_ROOT_JAVA_FRAME);
1598 writer()->write_objectID(o);
1599 writer()->write_u4(thread_serial_num);
1600 writer()->write_u4((u4) (stack_depth + extra_frames));
1601 }
1602 }
1603 }
1604 } else {
1605 // native frame
1606 if (stack_depth == 0) {
1607 // JNI locals for the top frame.
1608 java_thread->active_handles()->oops_do(&blk);
1609 } else {
1610 if (last_entry_frame != NULL) {
1611 // JNI locals for the entry frame
1612 assert(last_entry_frame->is_entry_frame(), "checking");
1613 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk);
1614 }
1615 }
1616 }
1617 // increment only for Java frames
1618 stack_depth++;
1619 last_entry_frame = NULL;
1621 } else {
1622 // externalVFrame - if it's an entry frame then report any JNI locals
1623 // as roots when we find the corresponding native javaVFrame
1624 frame* fr = vf->frame_pointer();
1625 assert(fr != NULL, "sanity check");
1626 if (fr->is_entry_frame()) {
1627 last_entry_frame = fr;
1628 }
1629 }
1630 vf = vf->sender();
1631 }
1632 } else {
1633 // no last java frame but there may be JNI locals
1634 java_thread->active_handles()->oops_do(&blk);
1635 }
1636 return stack_depth;
1637 }
1640 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk
1641 // the stack so that locals and JNI locals are dumped.
1642 void VM_HeapDumper::do_threads() {
1643 for (int i=0; i < _num_threads; i++) {
1644 JavaThread* thread = _stack_traces[i]->thread();
1645 oop threadObj = thread->threadObj();
1646 u4 thread_serial_num = i+1;
1647 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID;
1648 writer()->write_u1(HPROF_GC_ROOT_THREAD_OBJ);
1649 writer()->write_objectID(threadObj);
1650 writer()->write_u4(thread_serial_num); // thread number
1651 writer()->write_u4(stack_serial_num); // stack trace serial number
1652 int num_frames = do_thread(thread, thread_serial_num);
1653 assert(num_frames == _stack_traces[i]->get_stack_depth(),
1654 "total number of Java frames not matched");
1655 }
1656 }
1659 // The VM operation that dumps the heap. The dump consists of the following
1660 // records:
1661 //
1662 // HPROF_HEADER
1663 // [HPROF_UTF8]*
1664 // [HPROF_LOAD_CLASS]*
1665 // [[HPROF_FRAME]*|HPROF_TRACE]*
1666 // [HPROF_GC_CLASS_DUMP]*
1667 // HPROF_HEAP_DUMP
1668 //
1669 // The HPROF_TRACE records represent the stack traces where the heap dump
1670 // is generated and a "dummy trace" record which does not include
1671 // any frames. The dummy trace record is used to be referenced as the
1672 // unknown object alloc site.
1673 //
1674 // The HPROF_HEAP_DUMP record has a length following by sub-records. To allow
1675 // the heap dump be generated in a single pass we remember the position of
1676 // the dump length and fix it up after all sub-records have been written.
1677 // To generate the sub-records we iterate over the heap, writing
1678 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP
1679 // records as we go. Once that is done we write records for some of the GC
1680 // roots.
1682 void VM_HeapDumper::doit() {
1684 HandleMark hm;
1685 CollectedHeap* ch = Universe::heap();
1687 ch->ensure_parsability(false); // must happen, even if collection does
1688 // not happen (e.g. due to GC_locker)
1690 if (_gc_before_heap_dump) {
1691 if (GC_locker::is_active()) {
1692 warning("GC locker is held; pre-heapdump GC was skipped");
1693 } else {
1694 ch->collect_as_vm_thread(GCCause::_heap_dump);
1695 }
1696 }
1698 // At this point we should be the only dumper active, so
1699 // the following should be safe.
1700 set_global_dumper();
1701 set_global_writer();
1703 // Write the file header - use 1.0.2 for large heaps, otherwise 1.0.1
1704 size_t used = ch->used();
1705 const char* header;
1706 if (used > (size_t)SegmentedHeapDumpThreshold) {
1707 set_segmented_dump();
1708 header = "JAVA PROFILE 1.0.2";
1709 } else {
1710 header = "JAVA PROFILE 1.0.1";
1711 }
1713 // header is few bytes long - no chance to overflow int
1714 writer()->write_raw((void*)header, (int)strlen(header));
1715 writer()->write_u1(0); // terminator
1716 writer()->write_u4(oopSize);
1717 writer()->write_u8(os::javaTimeMillis());
1719 // HPROF_UTF8 records
1720 SymbolTableDumper sym_dumper(writer());
1721 SymbolTable::symbols_do(&sym_dumper);
1723 // write HPROF_LOAD_CLASS records
1724 SystemDictionary::classes_do(&do_load_class);
1725 Universe::basic_type_classes_do(&do_load_class);
1727 // write HPROF_FRAME and HPROF_TRACE records
1728 // this must be called after _klass_map is built when iterating the classes above.
1729 dump_stack_traces();
1731 // write HPROF_HEAP_DUMP or HPROF_HEAP_DUMP_SEGMENT
1732 write_dump_header();
1734 // Writes HPROF_GC_CLASS_DUMP records
1735 SystemDictionary::classes_do(&do_class_dump);
1736 Universe::basic_type_classes_do(&do_basic_type_array_class_dump);
1737 check_segment_length();
1739 // writes HPROF_GC_INSTANCE_DUMP records.
1740 // After each sub-record is written check_segment_length will be invoked. When
1741 // generated a segmented heap dump this allows us to check if the current
1742 // segment exceeds a threshold and if so, then a new segment is started.
1743 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk
1744 // of the heap dump.
1745 HeapObjectDumper obj_dumper(this, writer());
1746 Universe::heap()->safe_object_iterate(&obj_dumper);
1748 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
1749 do_threads();
1750 check_segment_length();
1752 // HPROF_GC_ROOT_MONITOR_USED
1753 MonitorUsedDumper mon_dumper(writer());
1754 ObjectSynchronizer::oops_do(&mon_dumper);
1755 check_segment_length();
1757 // HPROF_GC_ROOT_JNI_GLOBAL
1758 JNIGlobalsDumper jni_dumper(writer());
1759 JNIHandles::oops_do(&jni_dumper);
1760 check_segment_length();
1762 // HPROF_GC_ROOT_STICKY_CLASS
1763 StickyClassDumper class_dumper(writer());
1764 SystemDictionary::always_strong_classes_do(&class_dumper);
1766 // fixes up the length of the dump record. In the case of a segmented
1767 // heap then the HPROF_HEAP_DUMP_END record is also written.
1768 end_of_dump();
1770 // Now we clear the global variables, so that a future dumper might run.
1771 clear_global_dumper();
1772 clear_global_writer();
1773 }
1775 void VM_HeapDumper::dump_stack_traces() {
1776 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites
1777 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4));
1778 writer()->write_u4((u4) STACK_TRACE_ID);
1779 writer()->write_u4(0); // thread number
1780 writer()->write_u4(0); // frame count
1782 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal);
1783 int frame_serial_num = 0;
1784 for (JavaThread* thread = Threads::first(); thread != NULL ; thread = thread->next()) {
1785 oop threadObj = thread->threadObj();
1786 if (threadObj != NULL && !thread->is_exiting() && !thread->is_hidden_from_external_view()) {
1787 // dump thread stack trace
1788 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false);
1789 stack_trace->dump_stack_at_safepoint(-1);
1790 _stack_traces[_num_threads++] = stack_trace;
1792 // write HPROF_FRAME records for this thread's stack trace
1793 int depth = stack_trace->get_stack_depth();
1794 int thread_frame_start = frame_serial_num;
1795 int extra_frames = 0;
1796 // write fake frame that makes it look like the thread, which caused OOME,
1797 // is in the OutOfMemoryError zero-parameter constructor
1798 if (thread == _oome_thread && _oome_constructor != NULL) {
1799 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder());
1800 // the class serial number starts from 1
1801 assert(oome_serial_num > 0, "OutOfMemoryError class not found");
1802 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num,
1803 _oome_constructor, 0);
1804 extra_frames++;
1805 }
1806 for (int j=0; j < depth; j++) {
1807 StackFrameInfo* frame = stack_trace->stack_frame_at(j);
1808 Method* m = frame->method();
1809 int class_serial_num = _klass_map->find(m->method_holder());
1810 // the class serial number starts from 1
1811 assert(class_serial_num > 0, "class not found");
1812 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci());
1813 }
1814 depth += extra_frames;
1816 // write HPROF_TRACE record for one thread
1817 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize);
1818 int stack_serial_num = _num_threads + STACK_TRACE_ID;
1819 writer()->write_u4(stack_serial_num); // stack trace serial number
1820 writer()->write_u4((u4) _num_threads); // thread serial number
1821 writer()->write_u4(depth); // frame count
1822 for (int j=1; j <= depth; j++) {
1823 writer()->write_id(thread_frame_start + j);
1824 }
1825 }
1826 }
1827 }
1829 // dump the heap to given path.
1830 int HeapDumper::dump(const char* path) {
1831 assert(path != NULL && strlen(path) > 0, "path missing");
1833 // print message in interactive case
1834 if (print_to_tty()) {
1835 tty->print_cr("Dumping heap to %s ...", path);
1836 timer()->start();
1837 }
1839 // create the dump writer. If the file can be opened then bail
1840 DumpWriter writer(path);
1841 if (!writer.is_open()) {
1842 set_error(writer.error());
1843 if (print_to_tty()) {
1844 tty->print_cr("Unable to create %s: %s", path,
1845 (error() != NULL) ? error() : "reason unknown");
1846 }
1847 return -1;
1848 }
1850 // generate the dump
1851 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome);
1852 if (Thread::current()->is_VM_thread()) {
1853 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint");
1854 dumper.doit();
1855 } else {
1856 VMThread::execute(&dumper);
1857 }
1859 // close dump file and record any error that the writer may have encountered
1860 writer.close();
1861 set_error(writer.error());
1863 // print message in interactive case
1864 if (print_to_tty()) {
1865 timer()->stop();
1866 if (error() == NULL) {
1867 char msg[256];
1868 sprintf(msg, "Heap dump file created [%s bytes in %3.3f secs]",
1869 JLONG_FORMAT, timer()->seconds());
1870 tty->print_cr(msg, writer.bytes_written());
1871 } else {
1872 tty->print_cr("Dump file is incomplete: %s", writer.error());
1873 }
1874 }
1876 return (writer.error() == NULL) ? 0 : -1;
1877 }
1879 // stop timer (if still active), and free any error string we might be holding
1880 HeapDumper::~HeapDumper() {
1881 if (timer()->is_active()) {
1882 timer()->stop();
1883 }
1884 set_error(NULL);
1885 }
1888 // returns the error string (resource allocated), or NULL
1889 char* HeapDumper::error_as_C_string() const {
1890 if (error() != NULL) {
1891 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1);
1892 strcpy(str, error());
1893 return str;
1894 } else {
1895 return NULL;
1896 }
1897 }
1899 // set the error string
1900 void HeapDumper::set_error(char* error) {
1901 if (_error != NULL) {
1902 os::free(_error);
1903 }
1904 if (error == NULL) {
1905 _error = NULL;
1906 } else {
1907 _error = os::strdup(error);
1908 assert(_error != NULL, "allocation failure");
1909 }
1910 }
1912 // Called by out-of-memory error reporting by a single Java thread
1913 // outside of a JVM safepoint
1914 void HeapDumper::dump_heap_from_oome() {
1915 HeapDumper::dump_heap(true);
1916 }
1918 // Called by error reporting by a single Java thread outside of a JVM safepoint,
1919 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various
1920 // callers are strictly serialized and guaranteed not to interfere below. For more
1921 // general use, however, this method will need modification to prevent
1922 // inteference when updating the static variables base_path and dump_file_seq below.
1923 void HeapDumper::dump_heap() {
1924 HeapDumper::dump_heap(false);
1925 }
1927 void HeapDumper::dump_heap(bool oome) {
1928 static char base_path[JVM_MAXPATHLEN] = {'\0'};
1929 static uint dump_file_seq = 0;
1930 char* my_path;
1931 const int max_digit_chars = 20;
1933 const char* dump_file_name = "java_pid";
1934 const char* dump_file_ext = ".hprof";
1936 // The dump file defaults to java_pid<pid>.hprof in the current working
1937 // directory. HeapDumpPath=<file> can be used to specify an alternative
1938 // dump file name or a directory where dump file is created.
1939 if (dump_file_seq == 0) { // first time in, we initialize base_path
1940 // Calculate potentially longest base path and check if we have enough
1941 // allocated statically.
1942 const size_t total_length =
1943 (HeapDumpPath == NULL ? 0 : strlen(HeapDumpPath)) +
1944 strlen(os::file_separator()) + max_digit_chars +
1945 strlen(dump_file_name) + strlen(dump_file_ext) + 1;
1946 if (total_length > sizeof(base_path)) {
1947 warning("Cannot create heap dump file. HeapDumpPath is too long.");
1948 return;
1949 }
1951 bool use_default_filename = true;
1952 if (HeapDumpPath == NULL || HeapDumpPath[0] == '\0') {
1953 // HeapDumpPath=<file> not specified
1954 } else {
1955 strncpy(base_path, HeapDumpPath, sizeof(base_path));
1956 // check if the path is a directory (must exist)
1957 DIR* dir = os::opendir(base_path);
1958 if (dir == NULL) {
1959 use_default_filename = false;
1960 } else {
1961 // HeapDumpPath specified a directory. We append a file separator
1962 // (if needed).
1963 os::closedir(dir);
1964 size_t fs_len = strlen(os::file_separator());
1965 if (strlen(base_path) >= fs_len) {
1966 char* end = base_path;
1967 end += (strlen(base_path) - fs_len);
1968 if (strcmp(end, os::file_separator()) != 0) {
1969 strcat(base_path, os::file_separator());
1970 }
1971 }
1972 }
1973 }
1974 // If HeapDumpPath wasn't a file name then we append the default name
1975 if (use_default_filename) {
1976 const size_t dlen = strlen(base_path); // if heap dump dir specified
1977 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s",
1978 dump_file_name, os::current_process_id(), dump_file_ext);
1979 }
1980 const size_t len = strlen(base_path) + 1;
1981 my_path = (char*)os::malloc(len, mtInternal);
1982 if (my_path == NULL) {
1983 warning("Cannot create heap dump file. Out of system memory.");
1984 return;
1985 }
1986 strncpy(my_path, base_path, len);
1987 } else {
1988 // Append a sequence number id for dumps following the first
1989 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0
1990 my_path = (char*)os::malloc(len, mtInternal);
1991 if (my_path == NULL) {
1992 warning("Cannot create heap dump file. Out of system memory.");
1993 return;
1994 }
1995 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq);
1996 }
1997 dump_file_seq++; // increment seq number for next time we dump
1999 HeapDumper dumper(false /* no GC before heap dump */,
2000 true /* send to tty */,
2001 oome /* pass along out-of-memory-error flag */);
2002 dumper.dump(my_path);
2003 os::free(my_path);
2004 }