1 /*
2 * Copyright (c) 2002, 2009, 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 "incls/_precompiled.incl"
26 # include "incls/_heapInspection.cpp.incl"
27
28 // HeapInspection
29
30 int KlassInfoEntry::compare(KlassInfoEntry* e1, KlassInfoEntry* e2) {
31 if(e1->_instance_words > e2->_instance_words) {
32 return -1;
33 } else if(e1->_instance_words < e2->_instance_words) {
34 return 1;
35 }
36 return 0;
37 }
38
39 void KlassInfoEntry::print_on(outputStream* st) const {
40 ResourceMark rm;
41 const char* name;;
42 if (_klass->klass_part()->name() != NULL) {
43 name = _klass->klass_part()->external_name();
44 } else {
45 if (_klass == Universe::klassKlassObj()) name = "<klassKlass>"; else
46 if (_klass == Universe::arrayKlassKlassObj()) name = "<arrayKlassKlass>"; else
47 if (_klass == Universe::objArrayKlassKlassObj()) name = "<objArrayKlassKlass>"; else
48 if (_klass == Universe::instanceKlassKlassObj()) name = "<instanceKlassKlass>"; else
49 if (_klass == Universe::typeArrayKlassKlassObj()) name = "<typeArrayKlassKlass>"; else
50 if (_klass == Universe::symbolKlassObj()) name = "<symbolKlass>"; else
51 if (_klass == Universe::boolArrayKlassObj()) name = "<boolArrayKlass>"; else
52 if (_klass == Universe::charArrayKlassObj()) name = "<charArrayKlass>"; else
53 if (_klass == Universe::singleArrayKlassObj()) name = "<singleArrayKlass>"; else
54 if (_klass == Universe::doubleArrayKlassObj()) name = "<doubleArrayKlass>"; else
55 if (_klass == Universe::byteArrayKlassObj()) name = "<byteArrayKlass>"; else
56 if (_klass == Universe::shortArrayKlassObj()) name = "<shortArrayKlass>"; else
57 if (_klass == Universe::intArrayKlassObj()) name = "<intArrayKlass>"; else
58 if (_klass == Universe::longArrayKlassObj()) name = "<longArrayKlass>"; else
59 if (_klass == Universe::methodKlassObj()) name = "<methodKlass>"; else
60 if (_klass == Universe::constMethodKlassObj()) name = "<constMethodKlass>"; else
61 if (_klass == Universe::methodDataKlassObj()) name = "<methodDataKlass>"; else
62 if (_klass == Universe::constantPoolKlassObj()) name = "<constantPoolKlass>"; else
63 if (_klass == Universe::constantPoolCacheKlassObj()) name = "<constantPoolCacheKlass>"; else
64 if (_klass == Universe::compiledICHolderKlassObj()) name = "<compiledICHolderKlass>"; else
65 name = "<no name>";
66 }
67 // simplify the formatting (ILP32 vs LP64) - always cast the numbers to 64-bit
68 st->print_cr(INT64_FORMAT_W(13) " " UINT64_FORMAT_W(13) " %s",
69 (jlong) _instance_count,
70 (julong) _instance_words * HeapWordSize,
71 name);
72 }
73
74 KlassInfoEntry* KlassInfoBucket::lookup(const klassOop k) {
75 KlassInfoEntry* elt = _list;
76 while (elt != NULL) {
77 if (elt->is_equal(k)) {
78 return elt;
79 }
80 elt = elt->next();
81 }
82 elt = new KlassInfoEntry(k, list());
83 // We may be out of space to allocate the new entry.
84 if (elt != NULL) {
85 set_list(elt);
86 }
87 return elt;
88 }
89
90 void KlassInfoBucket::iterate(KlassInfoClosure* cic) {
91 KlassInfoEntry* elt = _list;
92 while (elt != NULL) {
93 cic->do_cinfo(elt);
94 elt = elt->next();
95 }
96 }
97
98 void KlassInfoBucket::empty() {
99 KlassInfoEntry* elt = _list;
100 _list = NULL;
101 while (elt != NULL) {
102 KlassInfoEntry* next = elt->next();
103 delete elt;
104 elt = next;
105 }
106 }
107
108 KlassInfoTable::KlassInfoTable(int size, HeapWord* ref) {
109 _size = 0;
110 _ref = ref;
111 _buckets = NEW_C_HEAP_ARRAY(KlassInfoBucket, size);
112 if (_buckets != NULL) {
113 _size = size;
114 for (int index = 0; index < _size; index++) {
115 _buckets[index].initialize();
116 }
117 }
118 }
119
120 KlassInfoTable::~KlassInfoTable() {
121 if (_buckets != NULL) {
122 for (int index = 0; index < _size; index++) {
123 _buckets[index].empty();
124 }
125 FREE_C_HEAP_ARRAY(KlassInfoBucket, _buckets);
126 _size = 0;
127 }
128 }
129
130 uint KlassInfoTable::hash(klassOop p) {
131 assert(Universe::heap()->is_in_permanent((HeapWord*)p), "all klasses in permgen");
132 return (uint)(((uintptr_t)p - (uintptr_t)_ref) >> 2);
133 }
134
135 KlassInfoEntry* KlassInfoTable::lookup(const klassOop k) {
136 uint idx = hash(k) % _size;
137 assert(_buckets != NULL, "Allocation failure should have been caught");
138 KlassInfoEntry* e = _buckets[idx].lookup(k);
139 // Lookup may fail if this is a new klass for which we
140 // could not allocate space for an new entry.
141 assert(e == NULL || k == e->klass(), "must be equal");
142 return e;
143 }
144
145 // Return false if the entry could not be recorded on account
146 // of running out of space required to create a new entry.
147 bool KlassInfoTable::record_instance(const oop obj) {
148 klassOop k = obj->klass();
149 KlassInfoEntry* elt = lookup(k);
150 // elt may be NULL if it's a new klass for which we
151 // could not allocate space for a new entry in the hashtable.
152 if (elt != NULL) {
153 elt->set_count(elt->count() + 1);
154 elt->set_words(elt->words() + obj->size());
155 return true;
156 } else {
157 return false;
158 }
159 }
160
161 void KlassInfoTable::iterate(KlassInfoClosure* cic) {
162 assert(_size == 0 || _buckets != NULL, "Allocation failure should have been caught");
163 for (int index = 0; index < _size; index++) {
164 _buckets[index].iterate(cic);
165 }
166 }
167
168 int KlassInfoHisto::sort_helper(KlassInfoEntry** e1, KlassInfoEntry** e2) {
169 return (*e1)->compare(*e1,*e2);
170 }
171
172 KlassInfoHisto::KlassInfoHisto(const char* title, int estimatedCount) :
173 _title(title) {
174 _elements = new (ResourceObj::C_HEAP) GrowableArray<KlassInfoEntry*>(estimatedCount,true);
175 }
176
177 KlassInfoHisto::~KlassInfoHisto() {
178 delete _elements;
179 }
180
181 void KlassInfoHisto::add(KlassInfoEntry* cie) {
182 elements()->append(cie);
183 }
184
185 void KlassInfoHisto::sort() {
186 elements()->sort(KlassInfoHisto::sort_helper);
187 }
188
189 void KlassInfoHisto::print_elements(outputStream* st) const {
190 // simplify the formatting (ILP32 vs LP64) - store the sum in 64-bit
191 jlong total = 0;
192 julong totalw = 0;
193 for(int i=0; i < elements()->length(); i++) {
194 st->print("%4d: ", i+1);
195 elements()->at(i)->print_on(st);
196 total += elements()->at(i)->count();
197 totalw += elements()->at(i)->words();
198 }
199 st->print_cr("Total " INT64_FORMAT_W(13) " " UINT64_FORMAT_W(13),
200 total, totalw * HeapWordSize);
201 }
202
203 void KlassInfoHisto::print_on(outputStream* st) const {
204 st->print_cr("%s",title());
205 print_elements(st);
206 }
207
208 class HistoClosure : public KlassInfoClosure {
209 private:
210 KlassInfoHisto* _cih;
211 public:
212 HistoClosure(KlassInfoHisto* cih) : _cih(cih) {}
213
214 void do_cinfo(KlassInfoEntry* cie) {
215 _cih->add(cie);
216 }
217 };
218
219 class RecordInstanceClosure : public ObjectClosure {
220 private:
221 KlassInfoTable* _cit;
222 size_t _missed_count;
223 public:
224 RecordInstanceClosure(KlassInfoTable* cit) :
225 _cit(cit), _missed_count(0) {}
226
227 void do_object(oop obj) {
228 if (!_cit->record_instance(obj)) {
229 _missed_count++;
230 }
231 }
232
233 size_t missed_count() { return _missed_count; }
234 };
235
236 void HeapInspection::heap_inspection(outputStream* st, bool need_prologue) {
237 ResourceMark rm;
238 HeapWord* ref;
239
240 CollectedHeap* heap = Universe::heap();
241 bool is_shared_heap = false;
242 switch (heap->kind()) {
243 case CollectedHeap::G1CollectedHeap:
244 case CollectedHeap::GenCollectedHeap: {
245 is_shared_heap = true;
246 SharedHeap* sh = (SharedHeap*)heap;
247 if (need_prologue) {
248 sh->gc_prologue(false /* !full */); // get any necessary locks, etc.
249 }
250 ref = sh->perm_gen()->used_region().start();
251 break;
252 }
253 #ifndef SERIALGC
254 case CollectedHeap::ParallelScavengeHeap: {
255 ParallelScavengeHeap* psh = (ParallelScavengeHeap*)heap;
256 ref = psh->perm_gen()->object_space()->used_region().start();
257 break;
258 }
259 #endif // SERIALGC
260 default:
261 ShouldNotReachHere(); // Unexpected heap kind for this op
262 }
263 // Collect klass instance info
264 KlassInfoTable cit(KlassInfoTable::cit_size, ref);
265 if (!cit.allocation_failed()) {
266 // Iterate over objects in the heap
267 RecordInstanceClosure ric(&cit);
268 // If this operation encounters a bad object when using CMS,
269 // consider using safe_object_iterate() which avoids perm gen
270 // objects that may contain bad references.
271 Universe::heap()->object_iterate(&ric);
272
273 // Report if certain classes are not counted because of
274 // running out of C-heap for the histogram.
275 size_t missed_count = ric.missed_count();
276 if (missed_count != 0) {
277 st->print_cr("WARNING: Ran out of C-heap; undercounted " SIZE_FORMAT
278 " total instances in data below",
279 missed_count);
280 }
281 // Sort and print klass instance info
282 KlassInfoHisto histo("\n"
283 " num #instances #bytes class name\n"
284 "----------------------------------------------",
285 KlassInfoHisto::histo_initial_size);
286 HistoClosure hc(&histo);
287 cit.iterate(&hc);
288 histo.sort();
289 histo.print_on(st);
290 } else {
291 st->print_cr("WARNING: Ran out of C-heap; histogram not generated");
292 }
293 st->flush();
294
295 if (need_prologue && is_shared_heap) {
296 SharedHeap* sh = (SharedHeap*)heap;
297 sh->gc_epilogue(false /* !full */); // release all acquired locks, etc.
298 }
299 }
300
301 class FindInstanceClosure : public ObjectClosure {
302 private:
303 klassOop _klass;
304 GrowableArray<oop>* _result;
305
306 public:
307 FindInstanceClosure(klassOop k, GrowableArray<oop>* result) : _klass(k), _result(result) {};
308
309 void do_object(oop obj) {
310 if (obj->is_a(_klass)) {
311 _result->append(obj);
312 }
313 }
314 };
315
316 void HeapInspection::find_instances_at_safepoint(klassOop k, GrowableArray<oop>* result) {
317 assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
318 assert(Heap_lock->is_locked(), "should have the Heap_lock");
319
320 // Ensure that the heap is parsable
321 Universe::heap()->ensure_parsability(false); // no need to retire TALBs
322
323 // Iterate over objects in the heap
324 FindInstanceClosure fic(k, result);
325 // If this operation encounters a bad object when using CMS,
326 // consider using safe_object_iterate() which avoids perm gen
327 // objects that may contain bad references.
328 Universe::heap()->object_iterate(&fic);
329 }