1 /*
2 * Copyright (c) 2005, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/classLoaderData.inline.hpp"
27 #include "classfile/classLoaderDataGraph.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "classfile/symbolTable.hpp"
30 #include "classfile/vmClasses.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "gc/shared/gcLocker.hpp"
33 #include "gc/shared/gcVMOperations.hpp"
34 #include "gc/shared/workerThread.hpp"
35 #include "jfr/jfrEvents.hpp"
36 #include "jvm.h"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "memory/universe.hpp"
40 #include "oops/klass.inline.hpp"
41 #include "oops/objArrayKlass.hpp"
42 #include "oops/objArrayOop.inline.hpp"
43 #include "oops/flatArrayKlass.hpp"
44 #include "oops/flatArrayOop.inline.hpp"
45 #include "oops/oop.inline.hpp"
46 #include "oops/typeArrayOop.inline.hpp"
47 #include "runtime/fieldDescriptor.inline.hpp"
48 #include "runtime/frame.inline.hpp"
49 #include "runtime/handles.inline.hpp"
50 #include "runtime/javaCalls.hpp"
51 #include "runtime/javaThread.inline.hpp"
52 #include "runtime/jniHandles.hpp"
53 #include "runtime/os.hpp"
54 #include "runtime/reflectionUtils.hpp"
55 #include "runtime/threads.hpp"
56 #include "runtime/threadSMR.hpp"
57 #include "runtime/vframe.hpp"
58 #include "runtime/vmOperations.hpp"
59 #include "runtime/vmThread.hpp"
60 #include "services/heapDumper.hpp"
61 #include "services/heapDumperCompression.hpp"
62 #include "services/threadService.hpp"
63 #include "utilities/macros.hpp"
64 #include "utilities/ostream.hpp"
65
66 /*
67 * HPROF binary format - description copied from:
68 * src/share/demo/jvmti/hprof/hprof_io.c
69 *
70 *
71 * header "JAVA PROFILE 1.0.2" (0-terminated)
72 *
73 * u4 size of identifiers. Identifiers are used to represent
74 * UTF8 strings, objects, stack traces, etc. They usually
75 * have the same size as host pointers.
76 * u4 high word
77 * u4 low word number of milliseconds since 0:00 GMT, 1/1/70
78 * [record]* a sequence of records.
79 *
80 *
81 * Record format:
82 *
83 * u1 a TAG denoting the type of the record
84 * u4 number of *microseconds* since the time stamp in the
85 * header. (wraps around in a little more than an hour)
86 * u4 number of bytes *remaining* in the record. Note that
87 * this number excludes the tag and the length field itself.
88 * [u1]* BODY of the record (a sequence of bytes)
89 *
90 *
91 * The following TAGs are supported:
92 *
93 * TAG BODY notes
94 *----------------------------------------------------------
95 * HPROF_UTF8 a UTF8-encoded name
96 *
97 * id name ID
98 * [u1]* UTF8 characters (no trailing zero)
99 *
100 * HPROF_LOAD_CLASS a newly loaded class
101 *
102 * u4 class serial number (> 0)
103 * id class object ID
104 * u4 stack trace serial number
105 * id class name ID
106 *
107 * HPROF_UNLOAD_CLASS an unloading class
108 *
109 * u4 class serial_number
110 *
111 * HPROF_FRAME a Java stack frame
112 *
113 * id stack frame ID
114 * id method name ID
115 * id method signature ID
116 * id source file name ID
117 * u4 class serial number
118 * i4 line number. >0: normal
119 * -1: unknown
120 * -2: compiled method
121 * -3: native method
122 *
123 * HPROF_TRACE a Java stack trace
124 *
125 * u4 stack trace serial number
126 * u4 thread serial number
127 * u4 number of frames
128 * [id]* stack frame IDs
129 *
130 *
131 * HPROF_ALLOC_SITES a set of heap allocation sites, obtained after GC
132 *
133 * u2 flags 0x0001: incremental vs. complete
134 * 0x0002: sorted by allocation vs. live
135 * 0x0004: whether to force a GC
136 * u4 cutoff ratio
137 * u4 total live bytes
138 * u4 total live instances
139 * u8 total bytes allocated
140 * u8 total instances allocated
141 * u4 number of sites that follow
142 * [u1 is_array: 0: normal object
143 * 2: object array
144 * 4: boolean array
145 * 5: char array
146 * 6: float array
147 * 7: double array
148 * 8: byte array
149 * 9: short array
150 * 10: int array
151 * 11: long array
152 * u4 class serial number (may be zero during startup)
153 * u4 stack trace serial number
154 * u4 number of bytes alive
155 * u4 number of instances alive
156 * u4 number of bytes allocated
157 * u4]* number of instance allocated
158 *
159 * HPROF_START_THREAD a newly started thread.
160 *
161 * u4 thread serial number (> 0)
162 * id thread object ID
163 * u4 stack trace serial number
164 * id thread name ID
165 * id thread group name ID
166 * id thread group parent name ID
167 *
168 * HPROF_END_THREAD a terminating thread.
169 *
170 * u4 thread serial number
171 *
172 * HPROF_HEAP_SUMMARY heap summary
173 *
174 * u4 total live bytes
175 * u4 total live instances
176 * u8 total bytes allocated
177 * u8 total instances allocated
178 *
179 * HPROF_HEAP_DUMP denote a heap dump
180 *
181 * [heap dump sub-records]*
182 *
183 * There are four kinds of heap dump sub-records:
184 *
185 * u1 sub-record type
186 *
187 * HPROF_GC_ROOT_UNKNOWN unknown root
188 *
189 * id object ID
190 *
191 * HPROF_GC_ROOT_THREAD_OBJ thread object
192 *
193 * id thread object ID (may be 0 for a
194 * thread newly attached through JNI)
195 * u4 thread sequence number
196 * u4 stack trace sequence number
197 *
198 * HPROF_GC_ROOT_JNI_GLOBAL JNI global ref root
199 *
200 * id object ID
201 * id JNI global ref ID
202 *
203 * HPROF_GC_ROOT_JNI_LOCAL JNI local ref
204 *
205 * id object ID
206 * u4 thread serial number
207 * u4 frame # in stack trace (-1 for empty)
208 *
209 * HPROF_GC_ROOT_JAVA_FRAME Java stack frame
210 *
211 * id object ID
212 * u4 thread serial number
213 * u4 frame # in stack trace (-1 for empty)
214 *
215 * HPROF_GC_ROOT_NATIVE_STACK Native stack
216 *
217 * id object ID
218 * u4 thread serial number
219 *
220 * HPROF_GC_ROOT_STICKY_CLASS System class
221 *
222 * id object ID
223 *
224 * HPROF_GC_ROOT_THREAD_BLOCK Reference from thread block
225 *
226 * id object ID
227 * u4 thread serial number
228 *
229 * HPROF_GC_ROOT_MONITOR_USED Busy monitor
230 *
231 * id object ID
232 *
233 * HPROF_GC_CLASS_DUMP dump of a class object
234 *
235 * id class object ID
236 * u4 stack trace serial number
237 * id super class object ID
238 * id class loader object ID
239 * id signers object ID
240 * id protection domain object ID
241 * id reserved
242 * id reserved
243 *
244 * u4 instance size (in bytes)
245 *
246 * u2 size of constant pool
247 * [u2, constant pool index,
248 * ty, type
249 * 2: object
250 * 4: boolean
251 * 5: char
252 * 6: float
253 * 7: double
254 * 8: byte
255 * 9: short
256 * 10: int
257 * 11: long
258 * vl]* and value
259 *
260 * u2 number of static fields
261 * [id, static field name,
262 * ty, type,
263 * vl]* and value
264 *
265 * u2 number of inst. fields (not inc. super)
266 * [id, instance field name,
267 * ty]* type
268 *
269 * HPROF_GC_INSTANCE_DUMP dump of a normal object
270 *
271 * id object ID
272 * u4 stack trace serial number
273 * id class object ID
274 * u4 number of bytes that follow
275 * [vl]* instance field values (class, followed
276 * by super, super's super ...)
277 *
278 * HPROF_GC_OBJ_ARRAY_DUMP dump of an object array
279 *
280 * id array object ID
281 * u4 stack trace serial number
282 * u4 number of elements
283 * id array class ID
284 * [id]* elements
285 *
286 * HPROF_GC_PRIM_ARRAY_DUMP dump of a primitive array
287 *
288 * id array object ID
289 * u4 stack trace serial number
290 * u4 number of elements
291 * u1 element type
292 * 4: boolean array
293 * 5: char array
294 * 6: float array
295 * 7: double array
296 * 8: byte array
297 * 9: short array
298 * 10: int array
299 * 11: long array
300 * [u1]* elements
301 *
302 * HPROF_CPU_SAMPLES a set of sample traces of running threads
303 *
304 * u4 total number of samples
305 * u4 # of traces
306 * [u4 # of samples
307 * u4]* stack trace serial number
308 *
309 * HPROF_CONTROL_SETTINGS the settings of on/off switches
310 *
311 * u4 0x00000001: alloc traces on/off
312 * 0x00000002: cpu sampling on/off
313 * u2 stack trace depth
314 *
315 * HPROF_FLAT_ARRAYS list of flat arrays
316 *
317 * [flat array sub-records]*
318 *
319 * HPROF_FLAT_ARRAY flat array
320 *
321 * id array object ID (dumped as HPROF_GC_PRIM_ARRAY_DUMP)
322 * id element class ID (dumped by HPROF_GC_CLASS_DUMP)
323 *
324 * HPROF_INLINED_FIELDS decribes inlined fields
325 *
326 * [class with inlined fields sub-records]*
327 *
328 * HPROF_CLASS_WITH_INLINED_FIELDS
329 *
330 * id class ID (dumped as HPROF_GC_CLASS_DUMP)
331 *
332 * u2 number of instance inlined fields (not including super)
333 * [u2, inlined field index,
334 * u2, synthetic field count,
335 * id, original field name,
336 * id]* inlined field class ID (dumped by HPROF_GC_CLASS_DUMP)
337 *
338 * When the header is "JAVA PROFILE 1.0.2" a heap dump can optionally
339 * be generated as a sequence of heap dump segments. This sequence is
340 * terminated by an end record. The additional tags allowed by format
341 * "JAVA PROFILE 1.0.2" are:
342 *
343 * HPROF_HEAP_DUMP_SEGMENT denote a heap dump segment
344 *
345 * [heap dump sub-records]*
346 * The same sub-record types allowed by HPROF_HEAP_DUMP
347 *
348 * HPROF_HEAP_DUMP_END denotes the end of a heap dump
349 *
350 */
351
352
353 // HPROF tags
354
355 enum hprofTag : u1 {
356 // top-level records
357 HPROF_UTF8 = 0x01,
358 HPROF_LOAD_CLASS = 0x02,
359 HPROF_UNLOAD_CLASS = 0x03,
360 HPROF_FRAME = 0x04,
361 HPROF_TRACE = 0x05,
362 HPROF_ALLOC_SITES = 0x06,
363 HPROF_HEAP_SUMMARY = 0x07,
364 HPROF_START_THREAD = 0x0A,
365 HPROF_END_THREAD = 0x0B,
366 HPROF_HEAP_DUMP = 0x0C,
367 HPROF_CPU_SAMPLES = 0x0D,
368 HPROF_CONTROL_SETTINGS = 0x0E,
369
370 // 1.0.2 record types
371 HPROF_HEAP_DUMP_SEGMENT = 0x1C,
372 HPROF_HEAP_DUMP_END = 0x2C,
373
374 // inlined object support
375 HPROF_FLAT_ARRAYS = 0x12,
376 HPROF_INLINED_FIELDS = 0x13,
377 // inlined object subrecords
378 HPROF_FLAT_ARRAY = 0x01,
379 HPROF_CLASS_WITH_INLINED_FIELDS = 0x01,
380
381 // field types
382 HPROF_ARRAY_OBJECT = 0x01,
383 HPROF_NORMAL_OBJECT = 0x02,
384 HPROF_BOOLEAN = 0x04,
385 HPROF_CHAR = 0x05,
386 HPROF_FLOAT = 0x06,
387 HPROF_DOUBLE = 0x07,
388 HPROF_BYTE = 0x08,
389 HPROF_SHORT = 0x09,
390 HPROF_INT = 0x0A,
391 HPROF_LONG = 0x0B,
392
393 // data-dump sub-records
394 HPROF_GC_ROOT_UNKNOWN = 0xFF,
395 HPROF_GC_ROOT_JNI_GLOBAL = 0x01,
396 HPROF_GC_ROOT_JNI_LOCAL = 0x02,
397 HPROF_GC_ROOT_JAVA_FRAME = 0x03,
398 HPROF_GC_ROOT_NATIVE_STACK = 0x04,
399 HPROF_GC_ROOT_STICKY_CLASS = 0x05,
400 HPROF_GC_ROOT_THREAD_BLOCK = 0x06,
401 HPROF_GC_ROOT_MONITOR_USED = 0x07,
402 HPROF_GC_ROOT_THREAD_OBJ = 0x08,
403 HPROF_GC_CLASS_DUMP = 0x20,
404 HPROF_GC_INSTANCE_DUMP = 0x21,
405 HPROF_GC_OBJ_ARRAY_DUMP = 0x22,
406 HPROF_GC_PRIM_ARRAY_DUMP = 0x23
407 };
408
409 // Default stack trace ID (used for dummy HPROF_TRACE record)
410 enum {
411 STACK_TRACE_ID = 1,
412 INITIAL_CLASS_COUNT = 200
413 };
414
415
416 class AbstractDumpWriter;
417
418 class InlinedObjects {
419
420 struct ClassInlinedFields {
421 const Klass *klass;
422 uintx base_index; // base index of the inlined field names (1st field has index base_index+1).
423 ClassInlinedFields(const Klass *klass = nullptr, uintx base_index = 0) : klass(klass), base_index(base_index) {}
424
425 // For GrowableArray::find_sorted().
426 static int compare(const ClassInlinedFields& a, const ClassInlinedFields& b) {
427 return a.klass - b.klass;
428 }
429 // For GrowableArray::sort().
430 static int compare(ClassInlinedFields* a, ClassInlinedFields* b) {
431 return compare(*a, *b);
432 }
433 };
434
435 uintx _min_string_id;
436 uintx _max_string_id;
437
438 GrowableArray<ClassInlinedFields> *_inlined_field_map;
439
440 // counters for classes with inlined fields and for the fields
441 int _classes_count;
442 int _inlined_fields_count;
443
444 static InlinedObjects *_instance;
445
446 static void inlined_field_names_callback(InlinedObjects* _this, const Klass *klass, uintx base_index, int count);
447
448 GrowableArray<oop> *_flat_arrays;
449
450 public:
451 InlinedObjects()
452 : _min_string_id(0), _max_string_id(0),
453 _inlined_field_map(nullptr),
454 _classes_count(0), _inlined_fields_count(0),
455 _flat_arrays(nullptr) {
456 }
457
458 static InlinedObjects* get_instance() {
459 return _instance;
460 }
461
462 void init();
463 void release();
464
465 void dump_inlined_field_names(AbstractDumpWriter *writer);
466
467 uintx get_base_index_for(Klass* k);
468 uintx get_next_string_id(uintx id);
469
470 void dump_classed_with_inlined_fields(AbstractDumpWriter* writer);
471
472 void add_flat_array(oop array);
473 void dump_flat_arrays(AbstractDumpWriter* writer);
474
475 };
476
477 InlinedObjects *InlinedObjects::_instance = nullptr;
478
479
480 // Supports I/O operations for a dump
481 // Base class for dump and parallel dump
482 class AbstractDumpWriter : public StackObj {
483 protected:
484 enum {
485 io_buffer_max_size = 1*M,
486 io_buffer_max_waste = 10*K,
487 dump_segment_header_size = 9
488 };
489
490 char* _buffer; // internal buffer
491 size_t _size;
492 size_t _pos;
493
494 bool _in_dump_segment; // Are we currently in a dump segment?
495 bool _is_huge_sub_record; // Are we writing a sub-record larger than the buffer size?
496 DEBUG_ONLY(size_t _sub_record_left;) // The bytes not written for the current sub-record.
497 DEBUG_ONLY(bool _sub_record_ended;) // True if we have called the end_sub_record().
498
499 virtual void flush(bool force = false) = 0;
500
501 char* buffer() const { return _buffer; }
502 size_t buffer_size() const { return _size; }
503 void set_position(size_t pos) { _pos = pos; }
504
505 // Can be called if we have enough room in the buffer.
506 void write_fast(const void* s, size_t len);
507
508 // Returns true if we have enough room in the buffer for 'len' bytes.
509 bool can_write_fast(size_t len);
510
511 void write_address(address a);
512
513 public:
514 AbstractDumpWriter() :
515 _buffer(nullptr),
516 _size(io_buffer_max_size),
517 _pos(0),
518 _in_dump_segment(false) { }
519
520 // total number of bytes written to the disk
521 virtual julong bytes_written() const = 0;
522 virtual char const* error() const = 0;
523
524 size_t position() const { return _pos; }
525 // writer functions
526 virtual void write_raw(const void* s, size_t len);
527 void write_u1(u1 x);
528 void write_u2(u2 x);
529 void write_u4(u4 x);
530 void write_u8(u8 x);
531 void write_objectID(oop o);
532 void write_rootID(oop* p);
533 void write_symbolID(Symbol* o);
534 void write_classID(Klass* k);
535 void write_id(u4 x);
536
537 // Start a new sub-record. Starts a new heap dump segment if needed.
538 void start_sub_record(u1 tag, u4 len);
539 // Ends the current sub-record.
540 void end_sub_record();
541 // Finishes the current dump segment if not already finished.
542 void finish_dump_segment(bool force_flush = false);
543 // Refresh to get new buffer
544 void refresh() {
545 assert (_in_dump_segment ==false, "Sanity check");
546 _buffer = nullptr;
547 _size = io_buffer_max_size;
548 _pos = 0;
549 // Force flush to guarantee data from parallel dumper are written.
550 flush(true);
551 }
552 // Called when finished to release the threads.
553 virtual void deactivate() = 0;
554 };
555
556 void AbstractDumpWriter::write_fast(const void* s, size_t len) {
557 assert(!_in_dump_segment || (_sub_record_left >= len), "sub-record too large");
558 assert(buffer_size() - position() >= len, "Must fit");
559 debug_only(_sub_record_left -= len);
560 memcpy(buffer() + position(), s, len);
561 set_position(position() + len);
562 }
563
564 bool AbstractDumpWriter::can_write_fast(size_t len) {
565 return buffer_size() - position() >= len;
566 }
567
568 // write raw bytes
569 void AbstractDumpWriter::write_raw(const void* s, size_t len) {
570 assert(!_in_dump_segment || (_sub_record_left >= len), "sub-record too large");
571 debug_only(_sub_record_left -= len);
572
573 // flush buffer to make room.
574 while (len > buffer_size() - position()) {
575 assert(!_in_dump_segment || _is_huge_sub_record,
576 "Cannot overflow in non-huge sub-record.");
577 size_t to_write = buffer_size() - position();
578 memcpy(buffer() + position(), s, to_write);
579 s = (void*) ((char*) s + to_write);
580 len -= to_write;
581 set_position(position() + to_write);
582 flush();
583 }
584
585 memcpy(buffer() + position(), s, len);
586 set_position(position() + len);
587 }
588
589 // Makes sure we inline the fast write into the write_u* functions. This is a big speedup.
590 #define WRITE_KNOWN_TYPE(p, len) do { if (can_write_fast((len))) write_fast((p), (len)); \
591 else write_raw((p), (len)); } while (0)
592
593 void AbstractDumpWriter::write_u1(u1 x) {
594 WRITE_KNOWN_TYPE(&x, 1);
595 }
596
597 void AbstractDumpWriter::write_u2(u2 x) {
598 u2 v;
599 Bytes::put_Java_u2((address)&v, x);
600 WRITE_KNOWN_TYPE(&v, 2);
601 }
602
603 void AbstractDumpWriter::write_u4(u4 x) {
604 u4 v;
605 Bytes::put_Java_u4((address)&v, x);
606 WRITE_KNOWN_TYPE(&v, 4);
607 }
608
609 void AbstractDumpWriter::write_u8(u8 x) {
610 u8 v;
611 Bytes::put_Java_u8((address)&v, x);
612 WRITE_KNOWN_TYPE(&v, 8);
613 }
614
615 void AbstractDumpWriter::write_address(address a) {
616 #ifdef _LP64
617 write_u8((u8)a);
618 #else
619 write_u4((u4)a);
620 #endif
621 }
622
623 void AbstractDumpWriter::write_objectID(oop o) {
624 write_address(cast_from_oop<address>(o));
625 }
626
627 void AbstractDumpWriter::write_rootID(oop* p) {
628 write_address((address)p);
629 }
630
631 void AbstractDumpWriter::write_symbolID(Symbol* s) {
632 write_address((address)((uintptr_t)s));
633 }
634
635 void AbstractDumpWriter::write_id(u4 x) {
636 #ifdef _LP64
637 write_u8((u8) x);
638 #else
639 write_u4(x);
640 #endif
641 }
642
643 // We use java mirror as the class ID
644 void AbstractDumpWriter::write_classID(Klass* k) {
645 write_objectID(k->java_mirror());
646 }
647
648 void AbstractDumpWriter::finish_dump_segment(bool force_flush) {
649 if (_in_dump_segment) {
650 assert(_sub_record_left == 0, "Last sub-record not written completely");
651 assert(_sub_record_ended, "sub-record must have ended");
652
653 // Fix up the dump segment length if we haven't written a huge sub-record last
654 // (in which case the segment length was already set to the correct value initially).
655 if (!_is_huge_sub_record) {
656 assert(position() > dump_segment_header_size, "Dump segment should have some content");
657 Bytes::put_Java_u4((address) (buffer() + 5),
658 (u4) (position() - dump_segment_header_size));
659 } else {
660 // Finish process huge sub record
661 // Set _is_huge_sub_record to false so the parallel dump writer can flush data to file.
662 _is_huge_sub_record = false;
663 }
664
665 _in_dump_segment = false;
666 flush(force_flush);
667 }
668 }
669
670 void AbstractDumpWriter::start_sub_record(u1 tag, u4 len) {
671 if (!_in_dump_segment) {
672 if (position() > 0) {
673 flush();
674 }
675
676 assert(position() == 0 && buffer_size() > dump_segment_header_size, "Must be at the start");
677
678 write_u1(HPROF_HEAP_DUMP_SEGMENT);
679 write_u4(0); // timestamp
680 // Will be fixed up later if we add more sub-records. If this is a huge sub-record,
681 // this is already the correct length, since we don't add more sub-records.
682 write_u4(len);
683 assert(Bytes::get_Java_u4((address)(buffer() + 5)) == len, "Inconsistent size!");
684 _in_dump_segment = true;
685 _is_huge_sub_record = len > buffer_size() - dump_segment_header_size;
686 } else if (_is_huge_sub_record || (len > buffer_size() - position())) {
687 // This object will not fit in completely or the last sub-record was huge.
688 // Finish the current segment and try again.
689 finish_dump_segment();
690 start_sub_record(tag, len);
691
692 return;
693 }
694
695 debug_only(_sub_record_left = len);
696 debug_only(_sub_record_ended = false);
697
698 write_u1(tag);
699 }
700
701 void AbstractDumpWriter::end_sub_record() {
702 assert(_in_dump_segment, "must be in dump segment");
703 assert(_sub_record_left == 0, "sub-record not written completely");
704 assert(!_sub_record_ended, "Must not have ended yet");
705 debug_only(_sub_record_ended = true);
706 }
707
708 // Supports I/O operations for a dump
709
710 class DumpWriter : public AbstractDumpWriter {
711 private:
712 CompressionBackend _backend; // Does the actual writing.
713 protected:
714 void flush(bool force = false) override;
715
716 public:
717 // Takes ownership of the writer and compressor.
718 DumpWriter(AbstractWriter* writer, AbstractCompressor* compressor);
719
720 // total number of bytes written to the disk
721 julong bytes_written() const override { return (julong) _backend.get_written(); }
722
723 char const* error() const override { return _backend.error(); }
724
725 // Called by threads used for parallel writing.
726 void writer_loop() { _backend.thread_loop(); }
727 // Called when finish to release the threads.
728 void deactivate() override { flush(); _backend.deactivate(); }
729 // Get the backend pointer, used by parallel dump writer.
730 CompressionBackend* backend_ptr() { return &_backend; }
731
732 };
733
734 // Check for error after constructing the object and destroy it in case of an error.
735 DumpWriter::DumpWriter(AbstractWriter* writer, AbstractCompressor* compressor) :
736 AbstractDumpWriter(),
737 _backend(writer, compressor, io_buffer_max_size, io_buffer_max_waste) {
738 flush();
739 }
740
741 // flush any buffered bytes to the file
742 void DumpWriter::flush(bool force) {
743 _backend.get_new_buffer(&_buffer, &_pos, &_size, force);
744 }
745
746 // Buffer queue used for parallel dump.
747 struct ParWriterBufferQueueElem {
748 char* _buffer;
749 size_t _used;
750 ParWriterBufferQueueElem* _next;
751 };
752
753 class ParWriterBufferQueue : public CHeapObj<mtInternal> {
754 private:
755 ParWriterBufferQueueElem* _head;
756 ParWriterBufferQueueElem* _tail;
757 uint _length;
758 public:
759 ParWriterBufferQueue() : _head(nullptr), _tail(nullptr), _length(0) { }
760
761 void enqueue(ParWriterBufferQueueElem* entry) {
762 if (_head == nullptr) {
763 assert(is_empty() && _tail == nullptr, "Sanity check");
764 _head = _tail = entry;
765 } else {
766 assert ((_tail->_next == nullptr && _tail->_buffer != nullptr), "Buffer queue is polluted");
767 _tail->_next = entry;
768 _tail = entry;
769 }
770 _length++;
771 assert(_tail->_next == nullptr, "Buffer queue is polluted");
772 }
773
774 ParWriterBufferQueueElem* dequeue() {
775 if (_head == nullptr) return nullptr;
776 ParWriterBufferQueueElem* entry = _head;
777 assert (entry->_buffer != nullptr, "polluted buffer in writer list");
778 _head = entry->_next;
779 if (_head == nullptr) {
780 _tail = nullptr;
781 }
782 entry->_next = nullptr;
783 _length--;
784 return entry;
785 }
786
787 bool is_empty() {
788 return _length == 0;
789 }
790
791 uint length() { return _length; }
792 };
793
794 // Support parallel heap dump.
795 class ParDumpWriter : public AbstractDumpWriter {
796 private:
797 // Lock used to guarantee the integrity of multiple buffers writing.
798 static Monitor* _lock;
799 // Pointer of backend from global DumpWriter.
800 CompressionBackend* _backend_ptr;
801 char const * _err;
802 ParWriterBufferQueue* _buffer_queue;
803 size_t _internal_buffer_used;
804 char* _buffer_base;
805 bool _split_data;
806 static const uint BackendFlushThreshold = 2;
807 protected:
808 void flush(bool force = false) override {
809 assert(_pos != 0, "must not be zero");
810 if (_pos != 0) {
811 refresh_buffer();
812 }
813
814 if (_split_data || _is_huge_sub_record) {
815 return;
816 }
817
818 if (should_flush_buf_list(force)) {
819 assert(!_in_dump_segment && !_split_data && !_is_huge_sub_record, "incomplete data send to backend!\n");
820 flush_to_backend(force);
821 }
822 }
823
824 public:
825 // Check for error after constructing the object and destroy it in case of an error.
826 ParDumpWriter(DumpWriter* dw) :
827 AbstractDumpWriter(),
828 _backend_ptr(dw->backend_ptr()),
829 _buffer_queue((new (std::nothrow) ParWriterBufferQueue())),
830 _buffer_base(nullptr),
831 _split_data(false) {
832 // prepare internal buffer
833 allocate_internal_buffer();
834 }
835
836 ~ParDumpWriter() {
837 assert(_buffer_queue != nullptr, "Sanity check");
838 assert((_internal_buffer_used == 0) && (_buffer_queue->is_empty()),
839 "All data must be send to backend");
840 if (_buffer_base != nullptr) {
841 os::free(_buffer_base);
842 _buffer_base = nullptr;
843 }
844 delete _buffer_queue;
845 _buffer_queue = nullptr;
846 }
847
848 // total number of bytes written to the disk
849 julong bytes_written() const override { return (julong) _backend_ptr->get_written(); }
850 char const* error() const override { return _err == nullptr ? _backend_ptr->error() : _err; }
851
852 static void before_work() {
853 assert(_lock == nullptr, "ParDumpWriter lock must be initialized only once");
854 _lock = new (std::nothrow) PaddedMonitor(Mutex::safepoint, "ParallelHProfWriter_lock");
855 }
856
857 static void after_work() {
858 assert(_lock != nullptr, "ParDumpWriter lock is not initialized");
859 delete _lock;
860 _lock = nullptr;
861 }
862
863 // write raw bytes
864 void write_raw(const void* s, size_t len) override {
865 assert(!_in_dump_segment || (_sub_record_left >= len), "sub-record too large");
866 debug_only(_sub_record_left -= len);
867 assert(!_split_data, "Invalid split data");
868 _split_data = true;
869 // flush buffer to make room.
870 while (len > buffer_size() - position()) {
871 assert(!_in_dump_segment || _is_huge_sub_record,
872 "Cannot overflow in non-huge sub-record.");
873 size_t to_write = buffer_size() - position();
874 memcpy(buffer() + position(), s, to_write);
875 s = (void*) ((char*) s + to_write);
876 len -= to_write;
877 set_position(position() + to_write);
878 flush();
879 }
880 _split_data = false;
881 memcpy(buffer() + position(), s, len);
882 set_position(position() + len);
883 }
884
885 void deactivate() override { flush(true); _backend_ptr->deactivate(); }
886
887 private:
888 void allocate_internal_buffer() {
889 assert(_buffer_queue != nullptr, "Internal buffer queue is not ready when allocate internal buffer");
890 assert(_buffer == nullptr && _buffer_base == nullptr, "current buffer must be null before allocate");
891 _buffer_base = _buffer = (char*)os::malloc(io_buffer_max_size, mtInternal);
892 if (_buffer == nullptr) {
893 set_error("Could not allocate buffer for writer");
894 return;
895 }
896 _pos = 0;
897 _internal_buffer_used = 0;
898 _size = io_buffer_max_size;
899 }
900
901 void set_error(char const* new_error) {
902 if ((new_error != nullptr) && (_err == nullptr)) {
903 _err = new_error;
904 }
905 }
906
907 // Add buffer to internal list
908 void refresh_buffer() {
909 size_t expected_total = _internal_buffer_used + _pos;
910 if (expected_total < io_buffer_max_size - io_buffer_max_waste) {
911 // reuse current buffer.
912 _internal_buffer_used = expected_total;
913 assert(_size - _pos == io_buffer_max_size - expected_total, "illegal resize of buffer");
914 _size -= _pos;
915 _buffer += _pos;
916 _pos = 0;
917
918 return;
919 }
920 // It is not possible here that expected_total is larger than io_buffer_max_size because
921 // of limitation in write_xxx().
922 assert(expected_total <= io_buffer_max_size, "buffer overflow");
923 assert(_buffer - _buffer_base <= io_buffer_max_size, "internal buffer overflow");
924 ParWriterBufferQueueElem* entry =
925 (ParWriterBufferQueueElem*)os::malloc(sizeof(ParWriterBufferQueueElem), mtInternal);
926 if (entry == nullptr) {
927 set_error("Heap dumper can allocate memory");
928 return;
929 }
930 entry->_buffer = _buffer_base;
931 entry->_used = expected_total;
932 entry->_next = nullptr;
933 // add to internal buffer queue
934 _buffer_queue->enqueue(entry);
935 _buffer_base =_buffer = nullptr;
936 allocate_internal_buffer();
937 }
938
939 void reclaim_entry(ParWriterBufferQueueElem* entry) {
940 assert(entry != nullptr && entry->_buffer != nullptr, "Invalid entry to reclaim");
941 os::free(entry->_buffer);
942 entry->_buffer = nullptr;
943 os::free(entry);
944 }
945
946 void flush_buffer(char* buffer, size_t used) {
947 assert(_lock->owner() == Thread::current(), "flush buffer must hold lock");
948 size_t max = io_buffer_max_size;
949 // get_new_buffer
950 _backend_ptr->flush_external_buffer(buffer, used, max);
951 }
952
953 bool should_flush_buf_list(bool force) {
954 return force || _buffer_queue->length() > BackendFlushThreshold;
955 }
956
957 void flush_to_backend(bool force) {
958 // Guarantee there is only one writer updating the backend buffers.
959 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
960 while (!_buffer_queue->is_empty()) {
961 ParWriterBufferQueueElem* entry = _buffer_queue->dequeue();
962 flush_buffer(entry->_buffer, entry->_used);
963 // Delete buffer and entry.
964 reclaim_entry(entry);
965 entry = nullptr;
966 }
967 assert(_pos == 0, "available buffer must be empty before flush");
968 // Flush internal buffer.
969 if (_internal_buffer_used > 0) {
970 flush_buffer(_buffer_base, _internal_buffer_used);
971 os::free(_buffer_base);
972 _pos = 0;
973 _internal_buffer_used = 0;
974 _buffer_base = _buffer = nullptr;
975 // Allocate internal buffer for future use.
976 allocate_internal_buffer();
977 }
978 }
979 };
980
981 Monitor* ParDumpWriter::_lock = nullptr;
982
983 // Support class with a collection of functions used when dumping the heap
984
985 class DumperSupport : AllStatic {
986 public:
987
988 // write a header of the given type
989 static void write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len);
990
991 // returns hprof tag for the given type signature
992 static hprofTag sig2tag(Symbol* sig);
993 // returns hprof tag for the given basic type
994 static hprofTag type2tag(BasicType type);
995 // Returns the size of the data to write.
996 static u4 sig2size(Symbol* sig);
997
998 // calculates the total size of the all fields of the given class.
999 static u4 instance_size(InstanceKlass* ik);
1000
1001 // dump a jfloat
1002 static void dump_float(AbstractDumpWriter* writer, jfloat f);
1003 // dump a jdouble
1004 static void dump_double(AbstractDumpWriter* writer, jdouble d);
1005 // dumps the raw value of the given field
1006 static void dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset);
1007 // returns the size of the static fields; also counts the static fields
1008 static u4 get_static_fields_size(InstanceKlass* ik, u2& field_count);
1009 // dumps static fields of the given class
1010 static void dump_static_fields(AbstractDumpWriter* writer, Klass* k);
1011 // dump the raw values of the instance fields of the given identity or inlined object;
1012 // for identity objects offset is 0 and 'klass' is o->klass(),
1013 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class
1014 static void dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, InstanceKlass* klass);
1015 // dump the raw values of the instance fields of the given inlined object;
1016 // dump_instance_fields wrapper for inlined objects
1017 static void dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, InlineKlass* klass);
1018
1019 // get the count of the instance fields for a given class
1020 static u2 get_instance_fields_count(InstanceKlass* ik);
1021 // dumps the definition of the instance fields for a given class
1022 static void dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* k, uintx *inlined_fields_index = nullptr);
1023 // creates HPROF_GC_INSTANCE_DUMP record for the given object
1024 static void dump_instance(AbstractDumpWriter* writer, oop o);
1025 // creates HPROF_GC_CLASS_DUMP record for the given instance class
1026 static void dump_instance_class(AbstractDumpWriter* writer, Klass* k);
1027 // creates HPROF_GC_CLASS_DUMP record for a given array class
1028 static void dump_array_class(AbstractDumpWriter* writer, Klass* k);
1029
1030 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1031 static void dump_object_array(AbstractDumpWriter* writer, objArrayOop array);
1032 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
1033 static void dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array);
1034 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1035 static void dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array);
1036 // create HPROF_FRAME record for the given method and bci
1037 static void dump_stack_frame(AbstractDumpWriter* writer, int frame_serial_num, int class_serial_num, Method* m, int bci);
1038
1039 // check if we need to truncate an array
1040 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size);
1041 // extended version to dump flat arrays as primitive arrays;
1042 // type_size specifies size of the inlined objects.
1043 static int calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size);
1044
1045 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
1046 static void end_of_dump(AbstractDumpWriter* writer);
1047
1048 static oop mask_dormant_archived_object(oop o) {
1049 if (o != nullptr && o->klass()->java_mirror() == nullptr) {
1050 // Ignore this object since the corresponding java mirror is not loaded.
1051 // Might be a dormant archive object.
1052 return nullptr;
1053 } else {
1054 return o;
1055 }
1056 }
1057
1058 // helper methods for inlined fields.
1059 static bool is_inlined_field(const FieldStream& fld) {
1060 return fld.field_descriptor().is_flat();
1061 }
1062 static InlineKlass* get_inlined_field_klass(const FieldStream &fld) {
1063 assert(is_inlined_field(fld), "must be inlined field");
1064 InstanceKlass* holder_klass = fld.field_descriptor().field_holder();
1065 return InlineKlass::cast(holder_klass->get_inline_type_field_klass(fld.index()));
1066 }
1067 };
1068
1069 // write a header of the given type
1070 void DumperSupport:: write_header(AbstractDumpWriter* writer, hprofTag tag, u4 len) {
1071 writer->write_u1(tag);
1072 writer->write_u4(0); // current ticks
1073 writer->write_u4(len);
1074 }
1075
1076 // returns hprof tag for the given type signature
1077 hprofTag DumperSupport::sig2tag(Symbol* sig) {
1078 switch (sig->char_at(0)) {
1079 case JVM_SIGNATURE_CLASS : return HPROF_NORMAL_OBJECT;
1080 case JVM_SIGNATURE_PRIMITIVE_OBJECT: return HPROF_NORMAL_OBJECT; // not inlined Q-object, i.e. identity object.
1081 case JVM_SIGNATURE_ARRAY : return HPROF_NORMAL_OBJECT;
1082 case JVM_SIGNATURE_BYTE : return HPROF_BYTE;
1083 case JVM_SIGNATURE_CHAR : return HPROF_CHAR;
1084 case JVM_SIGNATURE_FLOAT : return HPROF_FLOAT;
1085 case JVM_SIGNATURE_DOUBLE : return HPROF_DOUBLE;
1086 case JVM_SIGNATURE_INT : return HPROF_INT;
1087 case JVM_SIGNATURE_LONG : return HPROF_LONG;
1088 case JVM_SIGNATURE_SHORT : return HPROF_SHORT;
1089 case JVM_SIGNATURE_BOOLEAN : return HPROF_BOOLEAN;
1090 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
1091 }
1092 }
1093
1094 hprofTag DumperSupport::type2tag(BasicType type) {
1095 switch (type) {
1096 case T_BYTE : return HPROF_BYTE;
1097 case T_CHAR : return HPROF_CHAR;
1098 case T_FLOAT : return HPROF_FLOAT;
1099 case T_DOUBLE : return HPROF_DOUBLE;
1100 case T_INT : return HPROF_INT;
1101 case T_LONG : return HPROF_LONG;
1102 case T_SHORT : return HPROF_SHORT;
1103 case T_BOOLEAN : return HPROF_BOOLEAN;
1104 default : ShouldNotReachHere(); /* to shut up compiler */ return HPROF_BYTE;
1105 }
1106 }
1107
1108 u4 DumperSupport::sig2size(Symbol* sig) {
1109 switch (sig->char_at(0)) {
1110 case JVM_SIGNATURE_CLASS:
1111 case JVM_SIGNATURE_PRIMITIVE_OBJECT:
1112 case JVM_SIGNATURE_ARRAY: return sizeof(address);
1113 case JVM_SIGNATURE_BOOLEAN:
1114 case JVM_SIGNATURE_BYTE: return 1;
1115 case JVM_SIGNATURE_SHORT:
1116 case JVM_SIGNATURE_CHAR: return 2;
1117 case JVM_SIGNATURE_INT:
1118 case JVM_SIGNATURE_FLOAT: return 4;
1119 case JVM_SIGNATURE_LONG:
1120 case JVM_SIGNATURE_DOUBLE: return 8;
1121 default: ShouldNotReachHere(); /* to shut up compiler */ return 0;
1122 }
1123 }
1124
1125 template<typename T, typename F> T bit_cast(F from) { // replace with the real thing when we can use c++20
1126 T to;
1127 static_assert(sizeof(to) == sizeof(from), "must be of the same size");
1128 memcpy(&to, &from, sizeof(to));
1129 return to;
1130 }
1131
1132 // dump a jfloat
1133 void DumperSupport::dump_float(AbstractDumpWriter* writer, jfloat f) {
1134 if (g_isnan(f)) {
1135 writer->write_u4(0x7fc00000); // collapsing NaNs
1136 } else {
1137 writer->write_u4(bit_cast<u4>(f));
1138 }
1139 }
1140
1141 // dump a jdouble
1142 void DumperSupport::dump_double(AbstractDumpWriter* writer, jdouble d) {
1143 if (g_isnan(d)) {
1144 writer->write_u8(0x7ff80000ull << 32); // collapsing NaNs
1145 } else {
1146 writer->write_u8(bit_cast<u8>(d));
1147 }
1148 }
1149
1150
1151 // dumps the raw value of the given field
1152 void DumperSupport::dump_field_value(AbstractDumpWriter* writer, char type, oop obj, int offset) {
1153 switch (type) {
1154 case JVM_SIGNATURE_CLASS :
1155 case JVM_SIGNATURE_PRIMITIVE_OBJECT: // not inlined Q-object, i.e. identity object.
1156 case JVM_SIGNATURE_ARRAY : {
1157 oop o = obj->obj_field_access<ON_UNKNOWN_OOP_REF | AS_NO_KEEPALIVE>(offset);
1158 if (o != nullptr && log_is_enabled(Debug, cds, heap) && mask_dormant_archived_object(o) == nullptr) {
1159 ResourceMark rm;
1160 log_debug(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)",
1161 p2i(o), o->klass()->external_name(),
1162 p2i(obj), obj->klass()->external_name());
1163 }
1164 o = mask_dormant_archived_object(o);
1165 assert(oopDesc::is_oop_or_null(o), "Expected an oop or nullptr at " PTR_FORMAT, p2i(o));
1166 writer->write_objectID(o);
1167 break;
1168 }
1169 case JVM_SIGNATURE_BYTE : {
1170 jbyte b = obj->byte_field(offset);
1171 writer->write_u1(b);
1172 break;
1173 }
1174 case JVM_SIGNATURE_CHAR : {
1175 jchar c = obj->char_field(offset);
1176 writer->write_u2(c);
1177 break;
1178 }
1179 case JVM_SIGNATURE_SHORT : {
1180 jshort s = obj->short_field(offset);
1181 writer->write_u2(s);
1182 break;
1183 }
1184 case JVM_SIGNATURE_FLOAT : {
1185 jfloat f = obj->float_field(offset);
1186 dump_float(writer, f);
1187 break;
1188 }
1189 case JVM_SIGNATURE_DOUBLE : {
1190 jdouble d = obj->double_field(offset);
1191 dump_double(writer, d);
1192 break;
1193 }
1194 case JVM_SIGNATURE_INT : {
1195 jint i = obj->int_field(offset);
1196 writer->write_u4(i);
1197 break;
1198 }
1199 case JVM_SIGNATURE_LONG : {
1200 jlong l = obj->long_field(offset);
1201 writer->write_u8(l);
1202 break;
1203 }
1204 case JVM_SIGNATURE_BOOLEAN : {
1205 jboolean b = obj->bool_field(offset);
1206 writer->write_u1(b);
1207 break;
1208 }
1209 default : {
1210 ShouldNotReachHere();
1211 break;
1212 }
1213 }
1214 }
1215
1216 // calculates the total size of the all fields of the given class.
1217 u4 DumperSupport::instance_size(InstanceKlass *ik) {
1218 u4 size = 0;
1219
1220 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
1221 if (!fld.access_flags().is_static()) {
1222 if (is_inlined_field(fld)) {
1223 size += instance_size(get_inlined_field_klass(fld));
1224 } else {
1225 size += sig2size(fld.signature());
1226 }
1227 }
1228 }
1229 return size;
1230 }
1231
1232 u4 DumperSupport::get_static_fields_size(InstanceKlass* ik, u2& field_count) {
1233 field_count = 0;
1234 u4 size = 0;
1235
1236 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) {
1237 if (fldc.access_flags().is_static()) {
1238 assert(!is_inlined_field(fldc), "static fields cannot be inlined");
1239
1240 field_count++;
1241 size += sig2size(fldc.signature());
1242 }
1243 }
1244
1245 // Add in resolved_references which is referenced by the cpCache
1246 // The resolved_references is an array per InstanceKlass holding the
1247 // strings and other oops resolved from the constant pool.
1248 oop resolved_references = ik->constants()->resolved_references_or_null();
1249 if (resolved_references != nullptr) {
1250 field_count++;
1251 size += sizeof(address);
1252
1253 // Add in the resolved_references of the used previous versions of the class
1254 // in the case of RedefineClasses
1255 InstanceKlass* prev = ik->previous_versions();
1256 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1257 field_count++;
1258 size += sizeof(address);
1259 prev = prev->previous_versions();
1260 }
1261 }
1262
1263 // We write the value itself plus a name and a one byte type tag per field.
1264 return size + field_count * (sizeof(address) + 1);
1265 }
1266
1267 // dumps static fields of the given class
1268 void DumperSupport::dump_static_fields(AbstractDumpWriter* writer, Klass* k) {
1269 InstanceKlass* ik = InstanceKlass::cast(k);
1270
1271 // dump the field descriptors and raw values
1272 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) {
1273 if (fld.access_flags().is_static()) {
1274 assert(!is_inlined_field(fld), "static fields cannot be inlined");
1275
1276 Symbol* sig = fld.signature();
1277
1278 writer->write_symbolID(fld.name()); // name
1279 writer->write_u1(sig2tag(sig)); // type
1280
1281 // value
1282 dump_field_value(writer, sig->char_at(0), ik->java_mirror(), fld.offset());
1283 }
1284 }
1285
1286 // Add resolved_references for each class that has them
1287 oop resolved_references = ik->constants()->resolved_references_or_null();
1288 if (resolved_references != nullptr) {
1289 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1290 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1291 writer->write_objectID(resolved_references);
1292
1293 // Also write any previous versions
1294 InstanceKlass* prev = ik->previous_versions();
1295 while (prev != nullptr && prev->constants()->resolved_references_or_null() != nullptr) {
1296 writer->write_symbolID(vmSymbols::resolved_references_name()); // name
1297 writer->write_u1(sig2tag(vmSymbols::object_array_signature())); // type
1298 writer->write_objectID(prev->constants()->resolved_references());
1299 prev = prev->previous_versions();
1300 }
1301 }
1302 }
1303
1304 // dump the raw values of the instance fields of the given identity or inlined object;
1305 // for identity objects offset is 0 and 'klass' is o->klass(),
1306 // for inlined objects offset is the offset in the holder object, 'klass' is inlined object class.
1307 void DumperSupport::dump_instance_fields(AbstractDumpWriter* writer, oop o, int offset, InstanceKlass *klass) {
1308 for (FieldStream fld(klass, false, false); !fld.eos(); fld.next()) {
1309 if (!fld.access_flags().is_static()) {
1310 if (is_inlined_field(fld)) {
1311 InlineKlass* field_klass = get_inlined_field_klass(fld);
1312 // the field is inlined, so all its fields are stored without headers.
1313 int fields_offset = offset + fld.offset() - field_klass->first_field_offset();
1314 dump_inlined_object_fields(writer, o, offset + fld.offset(), field_klass);
1315 } else {
1316 Symbol* sig = fld.signature();
1317 dump_field_value(writer, sig->char_at(0), o, offset + fld.offset());
1318 }
1319 }
1320 }
1321 }
1322
1323 void DumperSupport::dump_inlined_object_fields(AbstractDumpWriter* writer, oop o, int offset, InlineKlass* klass) {
1324 // the object is inlined, so all its fields are stored without headers.
1325 dump_instance_fields(writer, o, offset - klass->first_field_offset(), klass);
1326 }
1327
1328 // gets the count of the instance fields for a given class
1329 u2 DumperSupport::get_instance_fields_count(InstanceKlass* ik) {
1330 u2 field_count = 0;
1331
1332 for (FieldStream fldc(ik, true, true); !fldc.eos(); fldc.next()) {
1333 if (!fldc.access_flags().is_static()) {
1334 if (is_inlined_field(fldc)) {
1335 // add "synthetic" fields for inlined fields.
1336 field_count += get_instance_fields_count(get_inlined_field_klass(fldc));
1337 } else {
1338 field_count++;
1339 }
1340 }
1341 }
1342
1343 return field_count;
1344 }
1345
1346 // dumps the definition of the instance fields for a given class
1347 // inlined_fields_id is not-nullptr for inlined fields (to get synthetic field name IDs
1348 // by using InlinedObjects::get_next_string_id()).
1349 void DumperSupport::dump_instance_field_descriptors(AbstractDumpWriter* writer, InstanceKlass* ik, uintx* inlined_fields_id) {
1350 // inlined_fields_id != nullptr means ik is a class of inlined field.
1351 // Inlined field id pointer for this class; lazyly initialized
1352 // if the class has inlined field(s) and the caller didn't provide inlined_fields_id.
1353 uintx *this_klass_inlined_fields_id = inlined_fields_id;
1354 uintx inlined_id = 0;
1355
1356 // dump the field descriptors
1357 for (FieldStream fld(ik, true, true); !fld.eos(); fld.next()) {
1358 if (!fld.access_flags().is_static()) {
1359 if (is_inlined_field(fld)) {
1360 // dump "synthetic" fields for inlined fields.
1361 if (this_klass_inlined_fields_id == nullptr) {
1362 inlined_id = InlinedObjects::get_instance()->get_base_index_for(ik);
1363 this_klass_inlined_fields_id = &inlined_id;
1364 }
1365 dump_instance_field_descriptors(writer, get_inlined_field_klass(fld), this_klass_inlined_fields_id);
1366 } else {
1367 Symbol* sig = fld.signature();
1368 Symbol* name = nullptr;
1369 // Use inlined_fields_id provided by caller.
1370 if (inlined_fields_id != nullptr) {
1371 uintx name_id = InlinedObjects::get_instance()->get_next_string_id(*inlined_fields_id);
1372
1373 // name_id == 0 is returned on error. use original field signature.
1374 if (name_id != 0) {
1375 *inlined_fields_id = name_id;
1376 name = reinterpret_cast<Symbol*>(name_id);
1377 }
1378 }
1379 if (name == nullptr) {
1380 name = fld.name();
1381 }
1382
1383 writer->write_symbolID(name); // name
1384 writer->write_u1(sig2tag(sig)); // type
1385 }
1386 }
1387 }
1388 }
1389
1390 // creates HPROF_GC_INSTANCE_DUMP record for the given object
1391 void DumperSupport::dump_instance(AbstractDumpWriter* writer, oop o) {
1392 InstanceKlass* ik = InstanceKlass::cast(o->klass());
1393 u4 is = instance_size(ik);
1394 u4 size = 1 + sizeof(address) + 4 + sizeof(address) + 4 + is;
1395
1396 writer->start_sub_record(HPROF_GC_INSTANCE_DUMP, size);
1397 writer->write_objectID(o);
1398 writer->write_u4(STACK_TRACE_ID);
1399
1400 // class ID
1401 writer->write_classID(ik);
1402
1403 // number of bytes that follow
1404 writer->write_u4(is);
1405
1406 // field values
1407 dump_instance_fields(writer, o, 0, ik);
1408
1409 writer->end_sub_record();
1410 }
1411
1412 // creates HPROF_GC_CLASS_DUMP record for the given instance class
1413 void DumperSupport::dump_instance_class(AbstractDumpWriter* writer, Klass* k) {
1414 InstanceKlass* ik = InstanceKlass::cast(k);
1415
1416 // We can safepoint and do a heap dump at a point where we have a Klass,
1417 // but no java mirror class has been setup for it. So we need to check
1418 // that the class is at least loaded, to avoid crash from a null mirror.
1419 if (!ik->is_loaded()) {
1420 return;
1421 }
1422
1423 u2 static_fields_count = 0;
1424 u4 static_size = get_static_fields_size(ik, static_fields_count);
1425 u2 instance_fields_count = get_instance_fields_count(ik);
1426 u4 instance_fields_size = instance_fields_count * (sizeof(address) + 1);
1427 u4 size = 1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + static_size + 2 + instance_fields_size;
1428
1429 writer->start_sub_record(HPROF_GC_CLASS_DUMP, size);
1430
1431 // class ID
1432 writer->write_classID(ik);
1433 writer->write_u4(STACK_TRACE_ID);
1434
1435 // super class ID
1436 InstanceKlass* java_super = ik->java_super();
1437 if (java_super == nullptr) {
1438 writer->write_objectID(oop(nullptr));
1439 } else {
1440 writer->write_classID(java_super);
1441 }
1442
1443 writer->write_objectID(ik->class_loader());
1444 writer->write_objectID(ik->signers());
1445 writer->write_objectID(ik->protection_domain());
1446
1447 // reserved
1448 writer->write_objectID(oop(nullptr));
1449 writer->write_objectID(oop(nullptr));
1450
1451 // instance size
1452 writer->write_u4(HeapWordSize * ik->size_helper());
1453
1454 // size of constant pool - ignored by HAT 1.1
1455 writer->write_u2(0);
1456
1457 // static fields
1458 writer->write_u2(static_fields_count);
1459 dump_static_fields(writer, ik);
1460
1461 // description of instance fields
1462 writer->write_u2(instance_fields_count);
1463 dump_instance_field_descriptors(writer, ik);
1464
1465 writer->end_sub_record();
1466 }
1467
1468 // creates HPROF_GC_CLASS_DUMP record for the given array class
1469 void DumperSupport::dump_array_class(AbstractDumpWriter* writer, Klass* k) {
1470 InstanceKlass* ik = nullptr; // bottom class for object arrays, null for primitive type arrays
1471 if (k->is_objArray_klass()) {
1472 Klass *bk = ObjArrayKlass::cast(k)->bottom_klass();
1473 assert(bk != nullptr, "checking");
1474 if (bk->is_instance_klass()) {
1475 ik = InstanceKlass::cast(bk);
1476 }
1477 }
1478
1479 u4 size = 1 + sizeof(address) + 4 + 6 * sizeof(address) + 4 + 2 + 2 + 2;
1480 writer->start_sub_record(HPROF_GC_CLASS_DUMP, size);
1481 writer->write_classID(k);
1482 writer->write_u4(STACK_TRACE_ID);
1483
1484 // super class of array classes is java.lang.Object
1485 InstanceKlass* java_super = k->java_super();
1486 assert(java_super != nullptr, "checking");
1487 writer->write_classID(java_super);
1488
1489 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->class_loader());
1490 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->signers());
1491 writer->write_objectID(ik == nullptr ? oop(nullptr) : ik->protection_domain());
1492
1493 writer->write_objectID(oop(nullptr)); // reserved
1494 writer->write_objectID(oop(nullptr));
1495 writer->write_u4(0); // instance size
1496 writer->write_u2(0); // constant pool
1497 writer->write_u2(0); // static fields
1498 writer->write_u2(0); // instance fields
1499
1500 writer->end_sub_record();
1501
1502 }
1503
1504 // Hprof uses an u4 as record length field,
1505 // which means we need to truncate arrays that are too long.
1506 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, int type_size, short header_size) {
1507 int length = array->length();
1508
1509 size_t length_in_bytes = (size_t)length * type_size;
1510 uint max_bytes = max_juint - header_size;
1511
1512 if (length_in_bytes > max_bytes) {
1513 length = max_bytes / type_size;
1514 length_in_bytes = (size_t)length * type_size;
1515
1516 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1517 warning("cannot dump array of type %s[] with length %d; truncating to length %d",
1518 type2name_tab[type], array->length(), length);
1519 }
1520 return length;
1521 }
1522
1523 int DumperSupport::calculate_array_max_length(AbstractDumpWriter* writer, arrayOop array, short header_size) {
1524 BasicType type = ArrayKlass::cast(array->klass())->element_type();
1525 assert((type >= T_BOOLEAN && type <= T_OBJECT) || type == T_PRIMITIVE_OBJECT, "invalid array element type");
1526 int type_size;
1527 if (type == T_OBJECT || type == T_PRIMITIVE_OBJECT) { // TODO: FIXME
1528 type_size = sizeof(address);
1529 } else {
1530 type_size = type2aelembytes(type);
1531 }
1532
1533 return calculate_array_max_length(writer, array, type_size, header_size);
1534 }
1535
1536 // creates HPROF_GC_OBJ_ARRAY_DUMP record for the given object array
1537 void DumperSupport::dump_object_array(AbstractDumpWriter* writer, objArrayOop array) {
1538 // sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID) + sizeof(classID)
1539 short header_size = 1 + 2 * 4 + 2 * sizeof(address);
1540 int length = calculate_array_max_length(writer, array, header_size);
1541 u4 size = header_size + length * sizeof(address);
1542
1543 writer->start_sub_record(HPROF_GC_OBJ_ARRAY_DUMP, size);
1544 writer->write_objectID(array);
1545 writer->write_u4(STACK_TRACE_ID);
1546 writer->write_u4(length);
1547
1548 // array class ID
1549 writer->write_classID(array->klass());
1550
1551 // [id]* elements
1552 for (int index = 0; index < length; index++) {
1553 oop o = array->obj_at(index);
1554 if (o != nullptr && log_is_enabled(Debug, cds, heap) && mask_dormant_archived_object(o) == nullptr) {
1555 ResourceMark rm;
1556 log_debug(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s) referenced by " INTPTR_FORMAT " (%s)",
1557 p2i(o), o->klass()->external_name(),
1558 p2i(array), array->klass()->external_name());
1559 }
1560 o = mask_dormant_archived_object(o);
1561 writer->write_objectID(o);
1562 }
1563
1564 writer->end_sub_record();
1565 }
1566
1567 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given flat array
1568 void DumperSupport::dump_flat_array(AbstractDumpWriter* writer, flatArrayOop array) {
1569 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
1570 InlineKlass* element_klass = array_klass->element_klass();
1571 int element_size = instance_size(element_klass);
1572 /* id array object ID
1573 * u4 stack trace serial number
1574 * u4 number of elements
1575 * u1 element type
1576 */
1577 short header_size = 1 + sizeof(address) + 2 * 4 + 1;
1578
1579 // TODO: use T_SHORT/T_INT/T_LONG if needed to avoid truncation
1580 BasicType type = T_BYTE;
1581 int type_size = type2aelembytes(type);
1582 int length = calculate_array_max_length(writer, array, element_size, header_size);
1583 u4 length_in_bytes = (u4)(length * element_size);
1584 u4 size = header_size + length_in_bytes;
1585
1586 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
1587 writer->write_objectID(array);
1588 writer->write_u4(STACK_TRACE_ID);
1589 // TODO: round up array length for T_SHORT/T_INT/T_LONG
1590 writer->write_u4(length * element_size);
1591 writer->write_u1(type2tag(type));
1592
1593 for (int index = 0; index < length; index++) {
1594 // need offset in the holder to read inlined object. calculate it from flatArrayOop::value_at_addr()
1595 int offset = (int)((address)array->value_at_addr(index, array_klass->layout_helper())
1596 - cast_from_oop<address>(array));
1597 dump_inlined_object_fields(writer, array, offset, element_klass);
1598 }
1599
1600 // TODO: write padding bytes for T_SHORT/T_INT/T_LONG
1601
1602 InlinedObjects::get_instance()->add_flat_array(array);
1603
1604 writer->end_sub_record();
1605 }
1606
1607 #define WRITE_ARRAY(Array, Type, Size, Length) \
1608 for (int i = 0; i < Length; i++) { writer->write_##Size((Size)Array->Type##_at(i)); }
1609
1610 // creates HPROF_GC_PRIM_ARRAY_DUMP record for the given type array
1611 void DumperSupport::dump_prim_array(AbstractDumpWriter* writer, typeArrayOop array) {
1612 BasicType type = TypeArrayKlass::cast(array->klass())->element_type();
1613 // 2 * sizeof(u1) + 2 * sizeof(u4) + sizeof(objectID)
1614 short header_size = 2 * 1 + 2 * 4 + sizeof(address);
1615
1616 int length = calculate_array_max_length(writer, array, header_size);
1617 int type_size = type2aelembytes(type);
1618 u4 length_in_bytes = (u4)length * type_size;
1619 u4 size = header_size + length_in_bytes;
1620
1621 writer->start_sub_record(HPROF_GC_PRIM_ARRAY_DUMP, size);
1622 writer->write_objectID(array);
1623 writer->write_u4(STACK_TRACE_ID);
1624 writer->write_u4(length);
1625 writer->write_u1(type2tag(type));
1626
1627 // nothing to copy
1628 if (length == 0) {
1629 writer->end_sub_record();
1630 return;
1631 }
1632
1633 // If the byte ordering is big endian then we can copy most types directly
1634
1635 switch (type) {
1636 case T_INT : {
1637 if (Endian::is_Java_byte_ordering_different()) {
1638 WRITE_ARRAY(array, int, u4, length);
1639 } else {
1640 writer->write_raw(array->int_at_addr(0), length_in_bytes);
1641 }
1642 break;
1643 }
1644 case T_BYTE : {
1645 writer->write_raw(array->byte_at_addr(0), length_in_bytes);
1646 break;
1647 }
1648 case T_CHAR : {
1649 if (Endian::is_Java_byte_ordering_different()) {
1650 WRITE_ARRAY(array, char, u2, length);
1651 } else {
1652 writer->write_raw(array->char_at_addr(0), length_in_bytes);
1653 }
1654 break;
1655 }
1656 case T_SHORT : {
1657 if (Endian::is_Java_byte_ordering_different()) {
1658 WRITE_ARRAY(array, short, u2, length);
1659 } else {
1660 writer->write_raw(array->short_at_addr(0), length_in_bytes);
1661 }
1662 break;
1663 }
1664 case T_BOOLEAN : {
1665 if (Endian::is_Java_byte_ordering_different()) {
1666 WRITE_ARRAY(array, bool, u1, length);
1667 } else {
1668 writer->write_raw(array->bool_at_addr(0), length_in_bytes);
1669 }
1670 break;
1671 }
1672 case T_LONG : {
1673 if (Endian::is_Java_byte_ordering_different()) {
1674 WRITE_ARRAY(array, long, u8, length);
1675 } else {
1676 writer->write_raw(array->long_at_addr(0), length_in_bytes);
1677 }
1678 break;
1679 }
1680
1681 // handle float/doubles in a special value to ensure than NaNs are
1682 // written correctly. TO DO: Check if we can avoid this on processors that
1683 // use IEEE 754.
1684
1685 case T_FLOAT : {
1686 for (int i = 0; i < length; i++) {
1687 dump_float(writer, array->float_at(i));
1688 }
1689 break;
1690 }
1691 case T_DOUBLE : {
1692 for (int i = 0; i < length; i++) {
1693 dump_double(writer, array->double_at(i));
1694 }
1695 break;
1696 }
1697 default : ShouldNotReachHere();
1698 }
1699
1700 writer->end_sub_record();
1701 }
1702
1703 // create a HPROF_FRAME record of the given Method* and bci
1704 void DumperSupport::dump_stack_frame(AbstractDumpWriter* writer,
1705 int frame_serial_num,
1706 int class_serial_num,
1707 Method* m,
1708 int bci) {
1709 int line_number;
1710 if (m->is_native()) {
1711 line_number = -3; // native frame
1712 } else {
1713 line_number = m->line_number_from_bci(bci);
1714 }
1715
1716 write_header(writer, HPROF_FRAME, 4*oopSize + 2*sizeof(u4));
1717 writer->write_id(frame_serial_num); // frame serial number
1718 writer->write_symbolID(m->name()); // method's name
1719 writer->write_symbolID(m->signature()); // method's signature
1720
1721 assert(m->method_holder()->is_instance_klass(), "not InstanceKlass");
1722 writer->write_symbolID(m->method_holder()->source_file_name()); // source file name
1723 writer->write_u4(class_serial_num); // class serial number
1724 writer->write_u4((u4) line_number); // line number
1725 }
1726
1727
1728 class InlinedFieldNameDumper : public LockedClassesDo {
1729 public:
1730 typedef void (*Callback)(InlinedObjects *owner, const Klass *klass, uintx base_index, int count);
1731
1732 private:
1733 AbstractDumpWriter* _writer;
1734 InlinedObjects *_owner;
1735 Callback _callback;
1736 uintx _index;
1737
1738 void dump_inlined_field_names(GrowableArray<Symbol*>* super_names, Symbol* field_name, InlineKlass* klass) {
1739 super_names->push(field_name);
1740 for (FieldStream fld(klass, false, false); !fld.eos(); fld.next()) {
1741 if (!fld.access_flags().is_static()) {
1742 if (DumperSupport::is_inlined_field(fld)) {
1743 dump_inlined_field_names(super_names, fld.name(), DumperSupport::get_inlined_field_klass(fld));
1744 } else {
1745 // get next string ID.
1746 uintx next_index = _owner->get_next_string_id(_index);
1747 if (next_index == 0) {
1748 // something went wrong (overflow?)
1749 // stop generation; the rest of inlined objects will have original field names.
1750 return;
1751 }
1752 _index = next_index;
1753
1754 // Calculate length.
1755 int len = fld.name()->utf8_length();
1756 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
1757 len += (*it)->utf8_length() + 1; // +1 for ".".
1758 }
1759
1760 DumperSupport::write_header(_writer, HPROF_UTF8, oopSize + len);
1761 _writer->write_symbolID(reinterpret_cast<Symbol*>(_index));
1762 // Write the string value.
1763 // 1) super_names.
1764 for (GrowableArrayIterator<Symbol*> it = super_names->begin(); it != super_names->end(); ++it) {
1765 _writer->write_raw((*it)->bytes(), (*it)->utf8_length());
1766 _writer->write_u1('.');
1767 }
1768 // 2) field name.
1769 _writer->write_raw(fld.name()->bytes(), fld.name()->utf8_length());
1770 }
1771 }
1772 }
1773 super_names->pop();
1774 }
1775
1776 void dump_inlined_field_names(Symbol* field_name, InlineKlass* field_klass) {
1777 GrowableArray<Symbol*> super_names(4, mtServiceability);
1778 dump_inlined_field_names(&super_names, field_name, field_klass);
1779 }
1780
1781 public:
1782 InlinedFieldNameDumper(AbstractDumpWriter* writer, InlinedObjects* owner, Callback callback)
1783 : _writer(writer), _owner(owner), _callback(callback), _index(0) {
1784 }
1785
1786 void do_klass(Klass* k) {
1787 if (!k->is_instance_klass()) {
1788 return;
1789 }
1790 InstanceKlass* ik = InstanceKlass::cast(k);
1791 // if (ik->has_inline_type_fields()) {
1792 // return;
1793 // }
1794
1795 uintx base_index = _index;
1796 int count = 0;
1797
1798 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
1799 if (!fld.access_flags().is_static()) {
1800 if (DumperSupport::is_inlined_field(fld)) {
1801 dump_inlined_field_names(fld.name(), DumperSupport::get_inlined_field_klass(fld));
1802 count++;
1803 }
1804 }
1805 }
1806
1807 if (count != 0) {
1808 _callback(_owner, k, base_index, count);
1809 }
1810 }
1811 };
1812
1813 class InlinedFieldsDumper : public LockedClassesDo {
1814 private:
1815 AbstractDumpWriter* _writer;
1816
1817 public:
1818 InlinedFieldsDumper(AbstractDumpWriter* writer) : _writer(writer) {}
1819
1820 void do_klass(Klass* k) {
1821 if (!k->is_instance_klass()) {
1822 return;
1823 }
1824 InstanceKlass* ik = InstanceKlass::cast(k);
1825 // if (ik->has_inline_type_fields()) {
1826 // return;
1827 // }
1828
1829 // We can be at a point where java mirror does not exist yet.
1830 // So we need to check that the class is at least loaded, to avoid crash from a null mirror.
1831 if (!ik->is_loaded()) {
1832 return;
1833 }
1834
1835 u2 inlined_count = 0;
1836 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
1837 if (!fld.access_flags().is_static()) {
1838 if (DumperSupport::is_inlined_field(fld)) {
1839 inlined_count++;
1840 }
1841 }
1842 }
1843 if (inlined_count != 0) {
1844 _writer->write_u1(HPROF_CLASS_WITH_INLINED_FIELDS);
1845
1846 // class ID
1847 _writer->write_classID(ik);
1848 // number of inlined fields
1849 _writer->write_u2(inlined_count);
1850 u2 index = 0;
1851 for (FieldStream fld(ik, false, false); !fld.eos(); fld.next()) {
1852 if (!fld.access_flags().is_static()) {
1853 if (DumperSupport::is_inlined_field(fld)) {
1854 // inlined field index
1855 _writer->write_u2(index);
1856 // synthetic field count
1857 u2 field_count = DumperSupport::get_instance_fields_count(DumperSupport::get_inlined_field_klass(fld));
1858 _writer->write_u2(field_count);
1859 // original field name
1860 _writer->write_symbolID(fld.name());
1861 // inlined field class ID
1862 _writer->write_classID(DumperSupport::get_inlined_field_klass(fld));
1863
1864 index += field_count;
1865 } else {
1866 index++;
1867 }
1868 }
1869 }
1870 }
1871 }
1872 };
1873
1874
1875 void InlinedObjects::init() {
1876 _instance = this;
1877
1878 struct Closure : public SymbolClosure {
1879 uintx _min_id = max_uintx;
1880 uintx _max_id = 0;
1881 Closure() : _min_id(max_uintx), _max_id(0) {}
1882
1883 void do_symbol(Symbol** p) {
1884 uintx val = reinterpret_cast<uintx>(*p);
1885 if (val < _min_id) {
1886 _min_id = val;
1887 }
1888 if (val > _max_id) {
1889 _max_id = val;
1890 }
1891 }
1892 } closure;
1893
1894 SymbolTable::symbols_do(&closure);
1895
1896 _min_string_id = closure._min_id;
1897 _max_string_id = closure._max_id;
1898 }
1899
1900 void InlinedObjects::release() {
1901 _instance = nullptr;
1902
1903 if (_inlined_field_map != nullptr) {
1904 delete _inlined_field_map;
1905 _inlined_field_map = nullptr;
1906 }
1907 if (_flat_arrays != nullptr) {
1908 delete _flat_arrays;
1909 _flat_arrays = nullptr;
1910 }
1911 }
1912
1913 void InlinedObjects::inlined_field_names_callback(InlinedObjects* _this, const Klass* klass, uintx base_index, int count) {
1914 if (_this->_inlined_field_map == nullptr) {
1915 _this->_inlined_field_map = new (mtServiceability) GrowableArray<ClassInlinedFields>(100, mtServiceability);
1916 }
1917 _this->_inlined_field_map->append(ClassInlinedFields(klass, base_index));
1918
1919 // counters for dumping classes with inlined fields
1920 _this->_classes_count++;
1921 _this->_inlined_fields_count += count;
1922 }
1923
1924 void InlinedObjects::dump_inlined_field_names(AbstractDumpWriter* writer) {
1925 InlinedFieldNameDumper nameDumper(writer, this, inlined_field_names_callback);
1926 ClassLoaderDataGraph::classes_do(&nameDumper);
1927
1928 if (_inlined_field_map != nullptr) {
1929 // prepare the map for get_base_index_for().
1930 _inlined_field_map->sort(ClassInlinedFields::compare);
1931 }
1932 }
1933
1934 uintx InlinedObjects::get_base_index_for(Klass* k) {
1935 if (_inlined_field_map != nullptr) {
1936 bool found = false;
1937 int idx = _inlined_field_map->find_sorted<ClassInlinedFields, ClassInlinedFields::compare>(ClassInlinedFields(k, 0), found);
1938 if (found) {
1939 return _inlined_field_map->at(idx).base_index;
1940 }
1941 }
1942
1943 // return max_uintx, so get_next_string_id returns 0.
1944 return max_uintx;
1945 }
1946
1947 uintx InlinedObjects::get_next_string_id(uintx id) {
1948 if (++id == _min_string_id) {
1949 return _max_string_id + 1;
1950 }
1951 return id;
1952 }
1953
1954 void InlinedObjects::dump_classed_with_inlined_fields(AbstractDumpWriter* writer) {
1955 if (_classes_count != 0) {
1956 // Record for each class contains tag(u1), class ID and count(u2)
1957 // for each inlined field index(u2), synthetic fields count(u2), original field name and class ID
1958 int size = _classes_count * (1 + sizeof(address) + 2)
1959 + _inlined_fields_count * (2 + 2 + sizeof(address) + sizeof(address));
1960 DumperSupport::write_header(writer, HPROF_INLINED_FIELDS, (u4)size);
1961
1962 InlinedFieldsDumper dumper(writer);
1963 ClassLoaderDataGraph::classes_do(&dumper);
1964 }
1965 }
1966
1967 void InlinedObjects::add_flat_array(oop array) {
1968 if (_flat_arrays == nullptr) {
1969 _flat_arrays = new (mtServiceability) GrowableArray<oop>(100, mtServiceability);
1970 }
1971 _flat_arrays->append(array);
1972 }
1973
1974 void InlinedObjects::dump_flat_arrays(AbstractDumpWriter* writer) {
1975 if (_flat_arrays != nullptr) {
1976 // For each flat array the record contains tag (u1), object ID and class ID.
1977 int size = _flat_arrays->length() * (1 + sizeof(address) + sizeof(address));
1978
1979 DumperSupport::write_header(writer, HPROF_FLAT_ARRAYS, (u4)size);
1980 for (GrowableArrayIterator<oop> it = _flat_arrays->begin(); it != _flat_arrays->end(); ++it) {
1981 flatArrayOop array = flatArrayOop(*it);
1982 FlatArrayKlass* array_klass = FlatArrayKlass::cast(array->klass());
1983 InlineKlass* element_klass = array_klass->element_klass();
1984 writer->write_u1(HPROF_FLAT_ARRAY);
1985 writer->write_objectID(array);
1986 writer->write_classID(element_klass);
1987 }
1988 }
1989 }
1990
1991
1992 // Support class used to generate HPROF_UTF8 records from the entries in the
1993 // SymbolTable.
1994
1995 class SymbolTableDumper : public SymbolClosure {
1996 private:
1997 AbstractDumpWriter* _writer;
1998 AbstractDumpWriter* writer() const { return _writer; }
1999 public:
2000 SymbolTableDumper(AbstractDumpWriter* writer) { _writer = writer; }
2001 void do_symbol(Symbol** p);
2002 };
2003
2004 void SymbolTableDumper::do_symbol(Symbol** p) {
2005 ResourceMark rm;
2006 Symbol* sym = *p;
2007 int len = sym->utf8_length();
2008 if (len > 0) {
2009 char* s = sym->as_utf8();
2010 DumperSupport::write_header(writer(), HPROF_UTF8, oopSize + len);
2011 writer()->write_symbolID(sym);
2012 writer()->write_raw(s, len);
2013 }
2014 }
2015
2016 // Support class used to generate HPROF_GC_ROOT_JNI_LOCAL records
2017
2018 class JNILocalsDumper : public OopClosure {
2019 private:
2020 AbstractDumpWriter* _writer;
2021 u4 _thread_serial_num;
2022 int _frame_num;
2023 AbstractDumpWriter* writer() const { return _writer; }
2024 public:
2025 JNILocalsDumper(AbstractDumpWriter* writer, u4 thread_serial_num) {
2026 _writer = writer;
2027 _thread_serial_num = thread_serial_num;
2028 _frame_num = -1; // default - empty stack
2029 }
2030 void set_frame_number(int n) { _frame_num = n; }
2031 void do_oop(oop* obj_p);
2032 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
2033 };
2034
2035
2036 void JNILocalsDumper::do_oop(oop* obj_p) {
2037 // ignore null handles
2038 oop o = *obj_p;
2039 if (o != nullptr) {
2040 u4 size = 1 + sizeof(address) + 4 + 4;
2041 writer()->start_sub_record(HPROF_GC_ROOT_JNI_LOCAL, size);
2042 writer()->write_objectID(o);
2043 writer()->write_u4(_thread_serial_num);
2044 writer()->write_u4((u4)_frame_num);
2045 writer()->end_sub_record();
2046 }
2047 }
2048
2049
2050 // Support class used to generate HPROF_GC_ROOT_JNI_GLOBAL records
2051
2052 class JNIGlobalsDumper : public OopClosure {
2053 private:
2054 AbstractDumpWriter* _writer;
2055 AbstractDumpWriter* writer() const { return _writer; }
2056
2057 public:
2058 JNIGlobalsDumper(AbstractDumpWriter* writer) {
2059 _writer = writer;
2060 }
2061 void do_oop(oop* obj_p);
2062 void do_oop(narrowOop* obj_p) { ShouldNotReachHere(); }
2063 };
2064
2065 void JNIGlobalsDumper::do_oop(oop* obj_p) {
2066 oop o = NativeAccess<AS_NO_KEEPALIVE>::oop_load(obj_p);
2067
2068 // ignore these
2069 if (o == nullptr) return;
2070 // we ignore global ref to symbols and other internal objects
2071 if (o->is_instance() || o->is_objArray() || o->is_typeArray()) {
2072 u4 size = 1 + 2 * sizeof(address);
2073 writer()->start_sub_record(HPROF_GC_ROOT_JNI_GLOBAL, size);
2074 writer()->write_objectID(o);
2075 writer()->write_rootID(obj_p); // global ref ID
2076 writer()->end_sub_record();
2077 }
2078 };
2079
2080 // Support class used to generate HPROF_GC_ROOT_STICKY_CLASS records
2081
2082 class StickyClassDumper : public KlassClosure {
2083 private:
2084 AbstractDumpWriter* _writer;
2085 AbstractDumpWriter* writer() const { return _writer; }
2086 public:
2087 StickyClassDumper(AbstractDumpWriter* writer) {
2088 _writer = writer;
2089 }
2090 void do_klass(Klass* k) {
2091 if (k->is_instance_klass()) {
2092 InstanceKlass* ik = InstanceKlass::cast(k);
2093 u4 size = 1 + sizeof(address);
2094 writer()->start_sub_record(HPROF_GC_ROOT_STICKY_CLASS, size);
2095 writer()->write_classID(ik);
2096 writer()->end_sub_record();
2097 }
2098 }
2099 };
2100
2101 // Large object heap dump support.
2102 // To avoid memory consumption, when dumping large objects such as huge array and
2103 // large objects whose size are larger than LARGE_OBJECT_DUMP_THRESHOLD, the scanned
2104 // partial object/array data will be sent to the backend directly instead of caching
2105 // the whole object/array in the internal buffer.
2106 // The HeapDumpLargeObjectList is used to save the large object when dumper scans
2107 // the heap. The large objects could be added (push) parallelly by multiple dumpers,
2108 // But they will be removed (popped) serially only by the VM thread.
2109 class HeapDumpLargeObjectList : public CHeapObj<mtInternal> {
2110 private:
2111 class HeapDumpLargeObjectListElem : public CHeapObj<mtInternal> {
2112 public:
2113 HeapDumpLargeObjectListElem(oop obj) : _obj(obj), _next(nullptr) { }
2114 oop _obj;
2115 HeapDumpLargeObjectListElem* _next;
2116 };
2117
2118 volatile HeapDumpLargeObjectListElem* _head;
2119
2120 public:
2121 HeapDumpLargeObjectList() : _head(nullptr) { }
2122
2123 void atomic_push(oop obj) {
2124 assert (obj != nullptr, "sanity check");
2125 HeapDumpLargeObjectListElem* entry = new HeapDumpLargeObjectListElem(obj);
2126 if (entry == nullptr) {
2127 warning("failed to allocate element for large object list");
2128 return;
2129 }
2130 assert (entry->_obj != nullptr, "sanity check");
2131 while (true) {
2132 volatile HeapDumpLargeObjectListElem* old_head = Atomic::load_acquire(&_head);
2133 HeapDumpLargeObjectListElem* new_head = entry;
2134 if (Atomic::cmpxchg(&_head, old_head, new_head) == old_head) {
2135 // successfully push
2136 new_head->_next = (HeapDumpLargeObjectListElem*)old_head;
2137 return;
2138 }
2139 }
2140 }
2141
2142 oop pop() {
2143 if (_head == nullptr) {
2144 return nullptr;
2145 }
2146 HeapDumpLargeObjectListElem* entry = (HeapDumpLargeObjectListElem*)_head;
2147 _head = _head->_next;
2148 assert (entry != nullptr, "illegal larger object list entry");
2149 oop ret = entry->_obj;
2150 delete entry;
2151 assert (ret != nullptr, "illegal oop pointer");
2152 return ret;
2153 }
2154
2155 void drain(ObjectClosure* cl) {
2156 while (_head != nullptr) {
2157 cl->do_object(pop());
2158 }
2159 }
2160
2161 bool is_empty() {
2162 return _head == nullptr;
2163 }
2164
2165 static const size_t LargeObjectSizeThreshold = 1 << 20; // 1 MB
2166 };
2167
2168 class VM_HeapDumper;
2169
2170 // Support class using when iterating over the heap.
2171 class HeapObjectDumper : public ObjectClosure {
2172 private:
2173 AbstractDumpWriter* _writer;
2174 HeapDumpLargeObjectList* _list;
2175
2176 AbstractDumpWriter* writer() { return _writer; }
2177 bool is_large(oop o);
2178 public:
2179 HeapObjectDumper(AbstractDumpWriter* writer, HeapDumpLargeObjectList* list = nullptr) {
2180 _writer = writer;
2181 _list = list;
2182 }
2183
2184 // called for each object in the heap
2185 void do_object(oop o);
2186 };
2187
2188 void HeapObjectDumper::do_object(oop o) {
2189 // skip classes as these emitted as HPROF_GC_CLASS_DUMP records
2190 if (o->klass() == vmClasses::Class_klass()) {
2191 if (!java_lang_Class::is_primitive(o)) {
2192 return;
2193 }
2194 }
2195
2196 if (DumperSupport::mask_dormant_archived_object(o) == nullptr) {
2197 log_debug(cds, heap)("skipped dormant archived object " INTPTR_FORMAT " (%s)", p2i(o), o->klass()->external_name());
2198 return;
2199 }
2200
2201 // If large object list exists and it is large object/array,
2202 // add oop into the list and skip scan. VM thread will process it later.
2203 if (_list != nullptr && is_large(o)) {
2204 _list->atomic_push(o);
2205 return;
2206 }
2207
2208 if (o->is_instance()) {
2209 // create a HPROF_GC_INSTANCE record for each object
2210 DumperSupport::dump_instance(writer(), o);
2211 } else if (o->is_objArray()) {
2212 // create a HPROF_GC_OBJ_ARRAY_DUMP record for each object array
2213 DumperSupport::dump_object_array(writer(), objArrayOop(o));
2214 } else if (o->is_flatArray()) {
2215 DumperSupport::dump_flat_array(writer(), flatArrayOop(o));
2216 } else if (o->is_typeArray()) {
2217 // create a HPROF_GC_PRIM_ARRAY_DUMP record for each type array
2218 DumperSupport::dump_prim_array(writer(), typeArrayOop(o));
2219 }
2220 }
2221
2222 bool HeapObjectDumper::is_large(oop o) {
2223 size_t size = 0;
2224 if (o->is_instance()) {
2225 // Use o->size() * 8 as the upper limit of instance size to avoid iterating static fields
2226 size = o->size() * 8;
2227 } else if (o->is_objArray()) {
2228 objArrayOop array = objArrayOop(o);
2229 BasicType type = ArrayKlass::cast(array->klass())->element_type();
2230 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
2231 int length = array->length();
2232 int type_size = sizeof(address);
2233 size = (size_t)length * type_size;
2234 } else if (o->is_typeArray()) {
2235 flatArrayOop array = flatArrayOop(o);
2236 BasicType type = ArrayKlass::cast(array->klass())->element_type();
2237 assert(type == T_PRIMITIVE_OBJECT, "invalid array element type");
2238 int length = array->length();
2239 //TODO: FIXME
2240 //int type_size = type2aelembytes(type);
2241 //size = (size_t)length * type_size;
2242 } else if (o->is_typeArray()) {
2243 typeArrayOop array = typeArrayOop(o);
2244 BasicType type = ArrayKlass::cast(array->klass())->element_type();
2245 assert(type >= T_BOOLEAN && type <= T_OBJECT, "invalid array element type");
2246 int length = array->length();
2247 int type_size = type2aelembytes(type);
2248 size = (size_t)length * type_size;
2249 }
2250 return size > HeapDumpLargeObjectList::LargeObjectSizeThreshold;
2251 }
2252
2253 // The dumper controller for parallel heap dump
2254 class DumperController : public CHeapObj<mtInternal> {
2255 private:
2256 bool _started;
2257 Monitor* _lock;
2258 uint _dumper_number;
2259 uint _complete_number;
2260
2261 public:
2262 DumperController(uint number) :
2263 _started(false),
2264 _lock(new (std::nothrow) PaddedMonitor(Mutex::safepoint, "DumperController_lock")),
2265 _dumper_number(number),
2266 _complete_number(0) { }
2267
2268 ~DumperController() { delete _lock; }
2269
2270 void wait_for_start_signal() {
2271 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2272 while (_started == false) {
2273 ml.wait();
2274 }
2275 assert(_started == true, "dumper woke up with wrong state");
2276 }
2277
2278 void start_dump() {
2279 assert (_started == false, "start dump with wrong state");
2280 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2281 _started = true;
2282 ml.notify_all();
2283 }
2284
2285 void dumper_complete() {
2286 assert (_started == true, "dumper complete with wrong state");
2287 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2288 _complete_number++;
2289 ml.notify();
2290 }
2291
2292 void wait_all_dumpers_complete() {
2293 assert (_started == true, "wrong state when wait for dumper complete");
2294 MonitorLocker ml(_lock, Mutex::_no_safepoint_check_flag);
2295 while (_complete_number != _dumper_number) {
2296 ml.wait();
2297 }
2298 _started = false;
2299 }
2300 };
2301
2302 // The VM operation that performs the heap dump
2303 class VM_HeapDumper : public VM_GC_Operation, public WorkerTask {
2304 private:
2305 static VM_HeapDumper* _global_dumper;
2306 static DumpWriter* _global_writer;
2307 DumpWriter* _local_writer;
2308 JavaThread* _oome_thread;
2309 Method* _oome_constructor;
2310 bool _gc_before_heap_dump;
2311 GrowableArray<Klass*>* _klass_map;
2312 ThreadStackTrace** _stack_traces;
2313 int _num_threads;
2314
2315 // Inlined object support.
2316 InlinedObjects _inlined_objects;
2317 InlinedObjects* inlined_objects() { return &_inlined_objects; }
2318
2319 // parallel heap dump support
2320 uint _num_dumper_threads;
2321 uint _num_writer_threads;
2322 DumperController* _dumper_controller;
2323 ParallelObjectIterator* _poi;
2324 HeapDumpLargeObjectList* _large_object_list;
2325
2326 // VMDumperType is for thread that dumps both heap and non-heap data.
2327 static const size_t VMDumperType = 0;
2328 static const size_t WriterType = 1;
2329 static const size_t DumperType = 2;
2330 // worker id of VMDumper thread.
2331 static const size_t VMDumperWorkerId = 0;
2332
2333 size_t get_worker_type(uint worker_id) {
2334 assert(_num_writer_threads >= 1, "Must be at least one writer");
2335 // worker id of VMDumper that dump heap and non-heap data
2336 if (worker_id == VMDumperWorkerId) {
2337 return VMDumperType;
2338 }
2339
2340 // worker id of dumper starts from 1, which only dump heap datar
2341 if (worker_id < _num_dumper_threads) {
2342 return DumperType;
2343 }
2344
2345 // worker id of writer starts from _num_dumper_threads
2346 return WriterType;
2347 }
2348
2349 void prepare_parallel_dump(uint num_total) {
2350 assert (_dumper_controller == nullptr, "dumper controller must be null");
2351 assert (num_total > 0, "active workers number must >= 1");
2352 // Dumper threads number must not be larger than active workers number.
2353 if (num_total < _num_dumper_threads) {
2354 _num_dumper_threads = num_total - 1;
2355 }
2356 // Calculate dumper and writer threads number.
2357 _num_writer_threads = num_total - _num_dumper_threads;
2358 // If dumper threads number is 1, only the VMThread works as a dumper.
2359 // If dumper threads number is equal to active workers, need at lest one worker thread as writer.
2360 if (_num_dumper_threads > 0 && _num_writer_threads == 0) {
2361 _num_writer_threads = 1;
2362 _num_dumper_threads = num_total - _num_writer_threads;
2363 }
2364 // Prepare parallel writer.
2365 if (_num_dumper_threads > 1) {
2366 ParDumpWriter::before_work();
2367 // Number of dumper threads that only iterate heap.
2368 uint _heap_only_dumper_threads = _num_dumper_threads - 1 /* VMDumper thread */;
2369 _dumper_controller = new (std::nothrow) DumperController(_heap_only_dumper_threads);
2370 }
2371 }
2372
2373 void finish_parallel_dump() {
2374 if (_num_dumper_threads > 1) {
2375 ParDumpWriter::after_work();
2376 }
2377 }
2378
2379 // accessors and setters
2380 static VM_HeapDumper* dumper() { assert(_global_dumper != nullptr, "Error"); return _global_dumper; }
2381 static DumpWriter* writer() { assert(_global_writer != nullptr, "Error"); return _global_writer; }
2382 void set_global_dumper() {
2383 assert(_global_dumper == nullptr, "Error");
2384 _global_dumper = this;
2385 }
2386 void set_global_writer() {
2387 assert(_global_writer == nullptr, "Error");
2388 _global_writer = _local_writer;
2389 }
2390 void clear_global_dumper() { _global_dumper = nullptr; }
2391 void clear_global_writer() { _global_writer = nullptr; }
2392
2393 bool skip_operation() const;
2394
2395 // writes a HPROF_LOAD_CLASS record
2396 static void do_load_class(Klass* k);
2397
2398 // writes a HPROF_GC_CLASS_DUMP record for the given class
2399 static void do_class_dump(Klass* k);
2400
2401 // HPROF_GC_ROOT_THREAD_OBJ records
2402 int do_thread(JavaThread* thread, u4 thread_serial_num);
2403 void do_threads();
2404
2405 void add_class_serial_number(Klass* k, int serial_num) {
2406 _klass_map->at_put_grow(serial_num, k);
2407 }
2408
2409 // HPROF_TRACE and HPROF_FRAME records
2410 void dump_stack_traces();
2411
2412 // large objects
2413 void dump_large_objects(ObjectClosure* writer);
2414
2415 public:
2416 VM_HeapDumper(DumpWriter* writer, bool gc_before_heap_dump, bool oome, uint num_dump_threads) :
2417 VM_GC_Operation(0 /* total collections, dummy, ignored */,
2418 GCCause::_heap_dump /* GC Cause */,
2419 0 /* total full collections, dummy, ignored */,
2420 gc_before_heap_dump),
2421 WorkerTask("dump heap") {
2422 _local_writer = writer;
2423 _gc_before_heap_dump = gc_before_heap_dump;
2424 _klass_map = new (mtServiceability) GrowableArray<Klass*>(INITIAL_CLASS_COUNT, mtServiceability);
2425 _stack_traces = nullptr;
2426 _num_threads = 0;
2427 _num_dumper_threads = num_dump_threads;
2428 _dumper_controller = nullptr;
2429 _poi = nullptr;
2430 _large_object_list = new (std::nothrow) HeapDumpLargeObjectList();
2431 if (oome) {
2432 assert(!Thread::current()->is_VM_thread(), "Dump from OutOfMemoryError cannot be called by the VMThread");
2433 // get OutOfMemoryError zero-parameter constructor
2434 InstanceKlass* oome_ik = vmClasses::OutOfMemoryError_klass();
2435 _oome_constructor = oome_ik->find_method(vmSymbols::object_initializer_name(),
2436 vmSymbols::void_method_signature());
2437 // get thread throwing OOME when generating the heap dump at OOME
2438 _oome_thread = JavaThread::current();
2439 } else {
2440 _oome_thread = nullptr;
2441 _oome_constructor = nullptr;
2442 }
2443 }
2444
2445 ~VM_HeapDumper() {
2446 if (_stack_traces != nullptr) {
2447 for (int i=0; i < _num_threads; i++) {
2448 delete _stack_traces[i];
2449 }
2450 FREE_C_HEAP_ARRAY(ThreadStackTrace*, _stack_traces);
2451 }
2452 if (_dumper_controller != nullptr) {
2453 delete _dumper_controller;
2454 _dumper_controller = nullptr;
2455 }
2456 delete _klass_map;
2457 delete _large_object_list;
2458 }
2459
2460 VMOp_Type type() const { return VMOp_HeapDumper; }
2461 virtual bool doit_prologue();
2462 void doit();
2463 void work(uint worker_id);
2464 };
2465
2466 VM_HeapDumper* VM_HeapDumper::_global_dumper = nullptr;
2467 DumpWriter* VM_HeapDumper::_global_writer = nullptr;
2468
2469 bool VM_HeapDumper::skip_operation() const {
2470 return false;
2471 }
2472
2473 // fixes up the current dump record and writes HPROF_HEAP_DUMP_END record
2474 void DumperSupport::end_of_dump(AbstractDumpWriter* writer) {
2475 writer->finish_dump_segment();
2476
2477 writer->write_u1(HPROF_HEAP_DUMP_END);
2478 writer->write_u4(0);
2479 writer->write_u4(0);
2480 }
2481
2482 // writes a HPROF_LOAD_CLASS record for the class
2483 void VM_HeapDumper::do_load_class(Klass* k) {
2484 static u4 class_serial_num = 0;
2485
2486 // len of HPROF_LOAD_CLASS record
2487 u4 remaining = 2*oopSize + 2*sizeof(u4);
2488
2489 DumperSupport::write_header(writer(), HPROF_LOAD_CLASS, remaining);
2490
2491 // class serial number is just a number
2492 writer()->write_u4(++class_serial_num);
2493
2494 // class ID
2495 writer()->write_classID(k);
2496
2497 // add the Klass* and class serial number pair
2498 dumper()->add_class_serial_number(k, class_serial_num);
2499
2500 writer()->write_u4(STACK_TRACE_ID);
2501
2502 // class name ID
2503 Symbol* name = k->name();
2504 writer()->write_symbolID(name);
2505 }
2506
2507 // writes a HPROF_GC_CLASS_DUMP record for the given class
2508 void VM_HeapDumper::do_class_dump(Klass* k) {
2509 if (k->is_instance_klass()) {
2510 DumperSupport::dump_instance_class(writer(), k);
2511 } else {
2512 DumperSupport::dump_array_class(writer(), k);
2513 }
2514 }
2515
2516 // Walk the stack of the given thread.
2517 // Dumps a HPROF_GC_ROOT_JAVA_FRAME record for each local
2518 // Dumps a HPROF_GC_ROOT_JNI_LOCAL record for each JNI local
2519 //
2520 // It returns the number of Java frames in this thread stack
2521 int VM_HeapDumper::do_thread(JavaThread* java_thread, u4 thread_serial_num) {
2522 JNILocalsDumper blk(writer(), thread_serial_num);
2523
2524 oop threadObj = java_thread->threadObj();
2525 assert(threadObj != nullptr, "sanity check");
2526
2527 int stack_depth = 0;
2528 if (java_thread->has_last_Java_frame()) {
2529
2530 // vframes are resource allocated
2531 Thread* current_thread = Thread::current();
2532 ResourceMark rm(current_thread);
2533 HandleMark hm(current_thread);
2534
2535 RegisterMap reg_map(java_thread,
2536 RegisterMap::UpdateMap::include,
2537 RegisterMap::ProcessFrames::include,
2538 RegisterMap::WalkContinuation::skip);
2539 frame f = java_thread->last_frame();
2540 vframe* vf = vframe::new_vframe(&f, ®_map, java_thread);
2541 frame* last_entry_frame = nullptr;
2542 int extra_frames = 0;
2543
2544 if (java_thread == _oome_thread && _oome_constructor != nullptr) {
2545 extra_frames++;
2546 }
2547 while (vf != nullptr) {
2548 blk.set_frame_number(stack_depth);
2549 if (vf->is_java_frame()) {
2550
2551 // java frame (interpreted, compiled, ...)
2552 javaVFrame *jvf = javaVFrame::cast(vf);
2553 if (!(jvf->method()->is_native())) {
2554 StackValueCollection* locals = jvf->locals();
2555 for (int slot=0; slot<locals->size(); slot++) {
2556 if (locals->at(slot)->type() == T_OBJECT) {
2557 oop o = locals->obj_at(slot)();
2558
2559 if (o != nullptr) {
2560 u4 size = 1 + sizeof(address) + 4 + 4;
2561 writer()->start_sub_record(HPROF_GC_ROOT_JAVA_FRAME, size);
2562 writer()->write_objectID(o);
2563 writer()->write_u4(thread_serial_num);
2564 writer()->write_u4((u4) (stack_depth + extra_frames));
2565 writer()->end_sub_record();
2566 }
2567 }
2568 }
2569 StackValueCollection *exprs = jvf->expressions();
2570 for(int index = 0; index < exprs->size(); index++) {
2571 if (exprs->at(index)->type() == T_OBJECT) {
2572 oop o = exprs->obj_at(index)();
2573 if (o != nullptr) {
2574 u4 size = 1 + sizeof(address) + 4 + 4;
2575 writer()->start_sub_record(HPROF_GC_ROOT_JAVA_FRAME, size);
2576 writer()->write_objectID(o);
2577 writer()->write_u4(thread_serial_num);
2578 writer()->write_u4((u4) (stack_depth + extra_frames));
2579 writer()->end_sub_record();
2580 }
2581 }
2582 }
2583 } else {
2584 // native frame
2585 if (stack_depth == 0) {
2586 // JNI locals for the top frame.
2587 java_thread->active_handles()->oops_do(&blk);
2588 } else {
2589 if (last_entry_frame != nullptr) {
2590 // JNI locals for the entry frame
2591 assert(last_entry_frame->is_entry_frame(), "checking");
2592 last_entry_frame->entry_frame_call_wrapper()->handles()->oops_do(&blk);
2593 }
2594 }
2595 }
2596 // increment only for Java frames
2597 stack_depth++;
2598 last_entry_frame = nullptr;
2599
2600 } else {
2601 // externalVFrame - if it's an entry frame then report any JNI locals
2602 // as roots when we find the corresponding native javaVFrame
2603 frame* fr = vf->frame_pointer();
2604 assert(fr != nullptr, "sanity check");
2605 if (fr->is_entry_frame()) {
2606 last_entry_frame = fr;
2607 }
2608 }
2609 vf = vf->sender();
2610 }
2611 } else {
2612 // no last java frame but there may be JNI locals
2613 java_thread->active_handles()->oops_do(&blk);
2614 }
2615 return stack_depth;
2616 }
2617
2618
2619 // write a HPROF_GC_ROOT_THREAD_OBJ record for each java thread. Then walk
2620 // the stack so that locals and JNI locals are dumped.
2621 void VM_HeapDumper::do_threads() {
2622 for (int i=0; i < _num_threads; i++) {
2623 JavaThread* thread = _stack_traces[i]->thread();
2624 oop threadObj = thread->threadObj();
2625 u4 thread_serial_num = i+1;
2626 u4 stack_serial_num = thread_serial_num + STACK_TRACE_ID;
2627 u4 size = 1 + sizeof(address) + 4 + 4;
2628 writer()->start_sub_record(HPROF_GC_ROOT_THREAD_OBJ, size);
2629 writer()->write_objectID(threadObj);
2630 writer()->write_u4(thread_serial_num); // thread number
2631 writer()->write_u4(stack_serial_num); // stack trace serial number
2632 writer()->end_sub_record();
2633 int num_frames = do_thread(thread, thread_serial_num);
2634 assert(num_frames == _stack_traces[i]->get_stack_depth(),
2635 "total number of Java frames not matched");
2636 }
2637 }
2638
2639 bool VM_HeapDumper::doit_prologue() {
2640 if (_gc_before_heap_dump && UseZGC) {
2641 // ZGC cannot perform a synchronous GC cycle from within the VM thread.
2642 // So ZCollectedHeap::collect_as_vm_thread() is a noop. To respect the
2643 // _gc_before_heap_dump flag a synchronous GC cycle is performed from
2644 // the caller thread in the prologue.
2645 Universe::heap()->collect(GCCause::_heap_dump);
2646 }
2647 return VM_GC_Operation::doit_prologue();
2648 }
2649
2650
2651 // The VM operation that dumps the heap. The dump consists of the following
2652 // records:
2653 //
2654 // HPROF_HEADER
2655 // [HPROF_UTF8]*
2656 // [HPROF_LOAD_CLASS]*
2657 // [[HPROF_FRAME]*|HPROF_TRACE]*
2658 // [HPROF_GC_CLASS_DUMP]*
2659 // [HPROF_HEAP_DUMP_SEGMENT]*
2660 // HPROF_HEAP_DUMP_END
2661 //
2662 // The HPROF_TRACE records represent the stack traces where the heap dump
2663 // is generated and a "dummy trace" record which does not include
2664 // any frames. The dummy trace record is used to be referenced as the
2665 // unknown object alloc site.
2666 //
2667 // Each HPROF_HEAP_DUMP_SEGMENT record has a length followed by sub-records.
2668 // To allow the heap dump be generated in a single pass we remember the position
2669 // of the dump length and fix it up after all sub-records have been written.
2670 // To generate the sub-records we iterate over the heap, writing
2671 // HPROF_GC_INSTANCE_DUMP, HPROF_GC_OBJ_ARRAY_DUMP, and HPROF_GC_PRIM_ARRAY_DUMP
2672 // records as we go. Once that is done we write records for some of the GC
2673 // roots.
2674
2675 void VM_HeapDumper::doit() {
2676
2677 CollectedHeap* ch = Universe::heap();
2678
2679 ch->ensure_parsability(false); // must happen, even if collection does
2680 // not happen (e.g. due to GCLocker)
2681
2682 if (_gc_before_heap_dump) {
2683 if (GCLocker::is_active()) {
2684 warning("GC locker is held; pre-heapdump GC was skipped");
2685 } else {
2686 ch->collect_as_vm_thread(GCCause::_heap_dump);
2687 }
2688 }
2689
2690 // At this point we should be the only dumper active, so
2691 // the following should be safe.
2692 set_global_dumper();
2693 set_global_writer();
2694
2695 WorkerThreads* workers = ch->safepoint_workers();
2696
2697 if (workers == nullptr) {
2698 // Use serial dump, set dumper threads and writer threads number to 1.
2699 _num_dumper_threads=1;
2700 _num_writer_threads=1;
2701 work(0);
2702 } else {
2703 prepare_parallel_dump(workers->active_workers());
2704 if (_num_dumper_threads > 1) {
2705 ParallelObjectIterator poi(_num_dumper_threads);
2706 _poi = &poi;
2707 workers->run_task(this);
2708 _poi = nullptr;
2709 } else {
2710 workers->run_task(this);
2711 }
2712 finish_parallel_dump();
2713 }
2714
2715 // Now we clear the global variables, so that a future dumper can run.
2716 clear_global_dumper();
2717 clear_global_writer();
2718 }
2719
2720 void VM_HeapDumper::work(uint worker_id) {
2721 if (worker_id != 0) {
2722 if (get_worker_type(worker_id) == WriterType) {
2723 writer()->writer_loop();
2724 return;
2725 }
2726 if (_num_dumper_threads > 1 && get_worker_type(worker_id) == DumperType) {
2727 _dumper_controller->wait_for_start_signal();
2728 }
2729 } else {
2730 // The worker 0 on all non-heap data dumping and part of heap iteration.
2731 // Write the file header - we always use 1.0.2
2732 const char* header = "JAVA PROFILE 1.0.2";
2733
2734 // header is few bytes long - no chance to overflow int
2735 writer()->write_raw(header, strlen(header) + 1); // NUL terminated
2736 writer()->write_u4(oopSize);
2737 // timestamp is current time in ms
2738 writer()->write_u8(os::javaTimeMillis());
2739 // HPROF_UTF8 records
2740 SymbolTableDumper sym_dumper(writer());
2741 SymbolTable::symbols_do(&sym_dumper);
2742
2743 // HPROF_UTF8 records for inlined field names.
2744 inlined_objects()->init();
2745 inlined_objects()->dump_inlined_field_names(writer());
2746
2747 // HPROF_INLINED_FIELDS
2748 inlined_objects()->dump_classed_with_inlined_fields(writer());
2749
2750 // write HPROF_LOAD_CLASS records
2751 {
2752 LockedClassesDo locked_load_classes(&do_load_class);
2753 ClassLoaderDataGraph::classes_do(&locked_load_classes);
2754 }
2755
2756 // write HPROF_FRAME and HPROF_TRACE records
2757 // this must be called after _klass_map is built when iterating the classes above.
2758 dump_stack_traces();
2759
2760 // Writes HPROF_GC_CLASS_DUMP records
2761 {
2762 LockedClassesDo locked_dump_class(&do_class_dump);
2763 ClassLoaderDataGraph::classes_do(&locked_dump_class);
2764 }
2765
2766 // HPROF_GC_ROOT_THREAD_OBJ + frames + jni locals
2767 do_threads();
2768
2769 // HPROF_GC_ROOT_JNI_GLOBAL
2770 JNIGlobalsDumper jni_dumper(writer());
2771 JNIHandles::oops_do(&jni_dumper);
2772 // technically not jni roots, but global roots
2773 // for things like preallocated throwable backtraces
2774 Universe::vm_global()->oops_do(&jni_dumper);
2775 // HPROF_GC_ROOT_STICKY_CLASS
2776 // These should be classes in the null class loader data, and not all classes
2777 // if !ClassUnloading
2778 StickyClassDumper class_dumper(writer());
2779 ClassLoaderData::the_null_class_loader_data()->classes_do(&class_dumper);
2780 }
2781 // writes HPROF_GC_INSTANCE_DUMP records.
2782 // After each sub-record is written check_segment_length will be invoked
2783 // to check if the current segment exceeds a threshold. If so, a new
2784 // segment is started.
2785 // The HPROF_GC_CLASS_DUMP and HPROF_GC_INSTANCE_DUMP are the vast bulk
2786 // of the heap dump.
2787 if (_num_dumper_threads <= 1) {
2788 HeapObjectDumper obj_dumper(writer());
2789 Universe::heap()->object_iterate(&obj_dumper);
2790 } else {
2791 assert(get_worker_type(worker_id) == DumperType
2792 || get_worker_type(worker_id) == VMDumperType,
2793 "must be dumper thread to do heap iteration");
2794 if (get_worker_type(worker_id) == VMDumperType) {
2795 // Clear global writer's buffer.
2796 writer()->finish_dump_segment(true);
2797 // Notify dumpers to start heap iteration.
2798 _dumper_controller->start_dump();
2799 }
2800 // Heap iteration.
2801 {
2802 ParDumpWriter pw(writer());
2803 {
2804 HeapObjectDumper obj_dumper(&pw, _large_object_list);
2805 _poi->object_iterate(&obj_dumper, worker_id);
2806 }
2807
2808 if (get_worker_type(worker_id) == VMDumperType) {
2809 _dumper_controller->wait_all_dumpers_complete();
2810 // clear internal buffer;
2811 pw.finish_dump_segment(true);
2812 // refresh the global_writer's buffer and position;
2813 writer()->refresh();
2814 } else {
2815 pw.finish_dump_segment(true);
2816 _dumper_controller->dumper_complete();
2817 return;
2818 }
2819 }
2820 }
2821
2822 assert(get_worker_type(worker_id) == VMDumperType, "Heap dumper must be VMDumper");
2823 // Use writer() rather than ParDumpWriter to avoid memory consumption.
2824 HeapObjectDumper obj_dumper(writer());
2825 dump_large_objects(&obj_dumper);
2826 // Writes the HPROF_HEAP_DUMP_END record.
2827 DumperSupport::end_of_dump(writer());
2828
2829 inlined_objects()->dump_flat_arrays(writer());
2830
2831 // We are done with writing. Release the worker threads.
2832 writer()->deactivate();
2833
2834 inlined_objects()->release();
2835 }
2836
2837 void VM_HeapDumper::dump_stack_traces() {
2838 // write a HPROF_TRACE record without any frames to be referenced as object alloc sites
2839 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4));
2840 writer()->write_u4((u4) STACK_TRACE_ID);
2841 writer()->write_u4(0); // thread number
2842 writer()->write_u4(0); // frame count
2843
2844 _stack_traces = NEW_C_HEAP_ARRAY(ThreadStackTrace*, Threads::number_of_threads(), mtInternal);
2845 int frame_serial_num = 0;
2846 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
2847 oop threadObj = thread->threadObj();
2848 if (threadObj != nullptr && !thread->is_exiting() && !thread->is_hidden_from_external_view()) {
2849 // dump thread stack trace
2850 Thread* current_thread = Thread::current();
2851 ResourceMark rm(current_thread);
2852 HandleMark hm(current_thread);
2853
2854 ThreadStackTrace* stack_trace = new ThreadStackTrace(thread, false);
2855 stack_trace->dump_stack_at_safepoint(-1, /* ObjectMonitorsHashtable is not needed here */ nullptr, true);
2856 _stack_traces[_num_threads++] = stack_trace;
2857
2858 // write HPROF_FRAME records for this thread's stack trace
2859 int depth = stack_trace->get_stack_depth();
2860 int thread_frame_start = frame_serial_num;
2861 int extra_frames = 0;
2862 // write fake frame that makes it look like the thread, which caused OOME,
2863 // is in the OutOfMemoryError zero-parameter constructor
2864 if (thread == _oome_thread && _oome_constructor != nullptr) {
2865 int oome_serial_num = _klass_map->find(_oome_constructor->method_holder());
2866 // the class serial number starts from 1
2867 assert(oome_serial_num > 0, "OutOfMemoryError class not found");
2868 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, oome_serial_num,
2869 _oome_constructor, 0);
2870 extra_frames++;
2871 }
2872 for (int j=0; j < depth; j++) {
2873 StackFrameInfo* frame = stack_trace->stack_frame_at(j);
2874 Method* m = frame->method();
2875 int class_serial_num = _klass_map->find(m->method_holder());
2876 // the class serial number starts from 1
2877 assert(class_serial_num > 0, "class not found");
2878 DumperSupport::dump_stack_frame(writer(), ++frame_serial_num, class_serial_num, m, frame->bci());
2879 }
2880 depth += extra_frames;
2881
2882 // write HPROF_TRACE record for one thread
2883 DumperSupport::write_header(writer(), HPROF_TRACE, 3*sizeof(u4) + depth*oopSize);
2884 int stack_serial_num = _num_threads + STACK_TRACE_ID;
2885 writer()->write_u4(stack_serial_num); // stack trace serial number
2886 writer()->write_u4((u4) _num_threads); // thread serial number
2887 writer()->write_u4(depth); // frame count
2888 for (int j=1; j <= depth; j++) {
2889 writer()->write_id(thread_frame_start + j);
2890 }
2891 }
2892 }
2893 }
2894
2895 // dump the large objects.
2896 void VM_HeapDumper::dump_large_objects(ObjectClosure* cl) {
2897 _large_object_list->drain(cl);
2898 }
2899
2900 // dump the heap to given path.
2901 int HeapDumper::dump(const char* path, outputStream* out, int compression, bool overwrite, uint num_dump_threads) {
2902 assert(path != nullptr && strlen(path) > 0, "path missing");
2903
2904 // print message in interactive case
2905 if (out != nullptr) {
2906 out->print_cr("Dumping heap to %s ...", path);
2907 timer()->start();
2908 }
2909 // create JFR event
2910 EventHeapDump event;
2911
2912 AbstractCompressor* compressor = nullptr;
2913
2914 if (compression > 0) {
2915 compressor = new (std::nothrow) GZipCompressor(compression);
2916
2917 if (compressor == nullptr) {
2918 set_error("Could not allocate gzip compressor");
2919 return -1;
2920 }
2921 }
2922
2923 DumpWriter writer(new (std::nothrow) FileWriter(path, overwrite), compressor);
2924
2925 if (writer.error() != nullptr) {
2926 set_error(writer.error());
2927 if (out != nullptr) {
2928 out->print_cr("Unable to create %s: %s", path,
2929 (error() != nullptr) ? error() : "reason unknown");
2930 }
2931 return -1;
2932 }
2933
2934 // generate the dump
2935 VM_HeapDumper dumper(&writer, _gc_before_heap_dump, _oome, num_dump_threads);
2936 if (Thread::current()->is_VM_thread()) {
2937 assert(SafepointSynchronize::is_at_safepoint(), "Expected to be called at a safepoint");
2938 dumper.doit();
2939 } else {
2940 VMThread::execute(&dumper);
2941 }
2942
2943 // record any error that the writer may have encountered
2944 set_error(writer.error());
2945
2946 // emit JFR event
2947 if (error() == nullptr) {
2948 event.set_destination(path);
2949 event.set_gcBeforeDump(_gc_before_heap_dump);
2950 event.set_size(writer.bytes_written());
2951 event.set_onOutOfMemoryError(_oome);
2952 event.set_overwrite(overwrite);
2953 event.set_compression(compression);
2954 event.commit();
2955 } else {
2956 log_debug(cds, heap)("Error %s while dumping heap", error());
2957 }
2958
2959 // print message in interactive case
2960 if (out != nullptr) {
2961 timer()->stop();
2962 if (error() == nullptr) {
2963 out->print_cr("Heap dump file created [" JULONG_FORMAT " bytes in %3.3f secs]",
2964 writer.bytes_written(), timer()->seconds());
2965 } else {
2966 out->print_cr("Dump file is incomplete: %s", writer.error());
2967 }
2968 }
2969
2970 return (writer.error() == nullptr) ? 0 : -1;
2971 }
2972
2973 // stop timer (if still active), and free any error string we might be holding
2974 HeapDumper::~HeapDumper() {
2975 if (timer()->is_active()) {
2976 timer()->stop();
2977 }
2978 set_error(nullptr);
2979 }
2980
2981
2982 // returns the error string (resource allocated), or null
2983 char* HeapDumper::error_as_C_string() const {
2984 if (error() != nullptr) {
2985 char* str = NEW_RESOURCE_ARRAY(char, strlen(error())+1);
2986 strcpy(str, error());
2987 return str;
2988 } else {
2989 return nullptr;
2990 }
2991 }
2992
2993 // set the error string
2994 void HeapDumper::set_error(char const* error) {
2995 if (_error != nullptr) {
2996 os::free(_error);
2997 }
2998 if (error == nullptr) {
2999 _error = nullptr;
3000 } else {
3001 _error = os::strdup(error);
3002 assert(_error != nullptr, "allocation failure");
3003 }
3004 }
3005
3006 // Called by out-of-memory error reporting by a single Java thread
3007 // outside of a JVM safepoint
3008 void HeapDumper::dump_heap_from_oome() {
3009 HeapDumper::dump_heap(true);
3010 }
3011
3012 // Called by error reporting by a single Java thread outside of a JVM safepoint,
3013 // or by heap dumping by the VM thread during a (GC) safepoint. Thus, these various
3014 // callers are strictly serialized and guaranteed not to interfere below. For more
3015 // general use, however, this method will need modification to prevent
3016 // inteference when updating the static variables base_path and dump_file_seq below.
3017 void HeapDumper::dump_heap() {
3018 HeapDumper::dump_heap(false);
3019 }
3020
3021 void HeapDumper::dump_heap(bool oome) {
3022 static char base_path[JVM_MAXPATHLEN] = {'\0'};
3023 static uint dump_file_seq = 0;
3024 char* my_path;
3025 const int max_digit_chars = 20;
3026
3027 const char* dump_file_name = "java_pid";
3028 const char* dump_file_ext = HeapDumpGzipLevel > 0 ? ".hprof.gz" : ".hprof";
3029
3030 // The dump file defaults to java_pid<pid>.hprof in the current working
3031 // directory. HeapDumpPath=<file> can be used to specify an alternative
3032 // dump file name or a directory where dump file is created.
3033 if (dump_file_seq == 0) { // first time in, we initialize base_path
3034 // Calculate potentially longest base path and check if we have enough
3035 // allocated statically.
3036 const size_t total_length =
3037 (HeapDumpPath == nullptr ? 0 : strlen(HeapDumpPath)) +
3038 strlen(os::file_separator()) + max_digit_chars +
3039 strlen(dump_file_name) + strlen(dump_file_ext) + 1;
3040 if (total_length > sizeof(base_path)) {
3041 warning("Cannot create heap dump file. HeapDumpPath is too long.");
3042 return;
3043 }
3044
3045 bool use_default_filename = true;
3046 if (HeapDumpPath == nullptr || HeapDumpPath[0] == '\0') {
3047 // HeapDumpPath=<file> not specified
3048 } else {
3049 strcpy(base_path, HeapDumpPath);
3050 // check if the path is a directory (must exist)
3051 DIR* dir = os::opendir(base_path);
3052 if (dir == nullptr) {
3053 use_default_filename = false;
3054 } else {
3055 // HeapDumpPath specified a directory. We append a file separator
3056 // (if needed).
3057 os::closedir(dir);
3058 size_t fs_len = strlen(os::file_separator());
3059 if (strlen(base_path) >= fs_len) {
3060 char* end = base_path;
3061 end += (strlen(base_path) - fs_len);
3062 if (strcmp(end, os::file_separator()) != 0) {
3063 strcat(base_path, os::file_separator());
3064 }
3065 }
3066 }
3067 }
3068 // If HeapDumpPath wasn't a file name then we append the default name
3069 if (use_default_filename) {
3070 const size_t dlen = strlen(base_path); // if heap dump dir specified
3071 jio_snprintf(&base_path[dlen], sizeof(base_path)-dlen, "%s%d%s",
3072 dump_file_name, os::current_process_id(), dump_file_ext);
3073 }
3074 const size_t len = strlen(base_path) + 1;
3075 my_path = (char*)os::malloc(len, mtInternal);
3076 if (my_path == nullptr) {
3077 warning("Cannot create heap dump file. Out of system memory.");
3078 return;
3079 }
3080 strncpy(my_path, base_path, len);
3081 } else {
3082 // Append a sequence number id for dumps following the first
3083 const size_t len = strlen(base_path) + max_digit_chars + 2; // for '.' and \0
3084 my_path = (char*)os::malloc(len, mtInternal);
3085 if (my_path == nullptr) {
3086 warning("Cannot create heap dump file. Out of system memory.");
3087 return;
3088 }
3089 jio_snprintf(my_path, len, "%s.%d", base_path, dump_file_seq);
3090 }
3091 dump_file_seq++; // increment seq number for next time we dump
3092
3093 HeapDumper dumper(false /* no GC before heap dump */,
3094 oome /* pass along out-of-memory-error flag */);
3095 dumper.dump(my_path, tty, HeapDumpGzipLevel);
3096 os::free(my_path);
3097 }