1 /*
2 * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #include "precompiled.hpp"
25
26 #include "gc_implementation/shenandoah/shenandoahAsserts.hpp"
27 #include "gc_implementation/shenandoah/shenandoahBrooksPointer.hpp"
28 #include "gc_implementation/shenandoah/shenandoahHeap.inline.hpp"
29 #include "gc_implementation/shenandoah/shenandoahMarkingContext.inline.hpp"
30 #include "gc_implementation/shenandoah/shenandoahUtils.hpp"
31 #include "memory/resourceArea.hpp"
32
33 void print_raw_memory(ShenandoahMessageBuffer &msg, void* loc) {
34 // Be extra safe. Only access data that is guaranteed to be safe:
35 // should be in heap, in known committed region, within that region.
36
37 ShenandoahHeap* heap = ShenandoahHeap::heap();
38 if (!heap->is_in(loc)) return;
39
40 ShenandoahHeapRegion* r = heap->heap_region_containing(loc);
41 if (r != NULL && r->is_committed()) {
42 address start = MAX2((address) r->bottom(), (address) loc - 32);
43 address end = MIN2((address) r->end(), (address) loc + 128);
44 if (start >= end) return;
45
46 stringStream ss;
47 os::print_hex_dump(&ss, start, end, 4);
48 msg.append("\n");
49 msg.append("Raw heap memory:\n%s", ss.as_string());
50 }
51 }
52
53 void ShenandoahAsserts::print_obj(ShenandoahMessageBuffer& msg, oop obj) {
54 ShenandoahHeap* heap = ShenandoahHeap::heap();
55 ShenandoahHeapRegion *r = heap->heap_region_containing(obj);
56
57 ResourceMark rm;
58 stringStream ss;
59 r->print_on(&ss);
60
61 ShenandoahMarkingContext* const ctx = heap->marking_context();
62
63 msg.append(" " PTR_FORMAT " - klass " PTR_FORMAT " %s\n", p2i(obj), p2i(obj->klass()), obj->klass()->external_name());
64 msg.append(" %3s allocated after mark start\n", ctx->allocated_after_mark_start((HeapWord *) obj) ? "" : "not");
65 msg.append(" %3s marked \n", ctx->is_marked(obj) ? "" : "not");
66 msg.append(" %3s in collection set\n", heap->in_collection_set(obj) ? "" : "not");
67 msg.append(" region: %s", ss.as_string());
68 }
69
70 void ShenandoahAsserts::print_non_obj(ShenandoahMessageBuffer& msg, void* loc) {
71 ShenandoahHeap* heap = ShenandoahHeap::heap();
72 if (heap->is_in(loc)) {
73 msg.append(" inside Java heap\n");
74 ShenandoahHeapRegion *r = heap->heap_region_containing(loc);
75 stringStream ss;
76 r->print_on(&ss);
77
78 msg.append(" %3s in collection set\n", heap->in_collection_set(loc) ? "" : "not");
79 msg.append(" region: %s", ss.as_string());
80 } else {
81 msg.append(" outside of Java heap\n");
82 stringStream ss;
83 os::print_location(&ss, (intptr_t) loc, false);
84 msg.append(" %s", ss.as_string());
85 }
86 }
87
88 void ShenandoahAsserts::print_obj_safe(ShenandoahMessageBuffer& msg, void* loc) {
89 ShenandoahHeap* heap = ShenandoahHeap::heap();
90 msg.append(" " PTR_FORMAT " - safe print, no details\n", p2i(loc));
91 if (heap->is_in(loc)) {
92 ShenandoahHeapRegion* r = heap->heap_region_containing(loc);
93 if (r != NULL) {
94 stringStream ss;
95 r->print_on(&ss);
96 msg.append(" region: %s", ss.as_string());
97 print_raw_memory(msg, loc);
98 }
99 }
100 }
101
102 void ShenandoahAsserts::print_failure(SafeLevel level, oop obj, void* interior_loc, oop loc,
103 const char* phase, const char* label,
104 const char* file, int line) {
105 ShenandoahHeap* heap = ShenandoahHeap::heap();
106 ResourceMark rm;
107
108 bool loc_in_heap = (loc != NULL && heap->is_in(loc));
109
110 ShenandoahMessageBuffer msg("%s; %s\n\n", phase, label);
111
112 msg.append("Referenced from:\n");
113 if (interior_loc != NULL) {
114 msg.append(" interior location: " PTR_FORMAT "\n", p2i(interior_loc));
115 if (loc_in_heap) {
116 print_obj(msg, loc);
117 } else {
118 print_non_obj(msg, interior_loc);
119 }
120 } else {
121 msg.append(" no interior location recorded (probably a plain heap scan, or detached oop)\n");
122 }
123 msg.append("\n");
124
125 msg.append("Object:\n");
126 if (level >= _safe_oop) {
127 print_obj(msg, obj);
128 } else {
129 print_obj_safe(msg, obj);
130 }
131 msg.append("\n");
132
133 if (level >= _safe_oop) {
134 oop fwd = (oop) ShenandoahBrooksPointer::get_raw_unchecked(obj);
135 msg.append("Forwardee:\n");
136 if (!oopDesc::unsafe_equals(obj, fwd)) {
137 if (level >= _safe_oop_fwd) {
138 print_obj(msg, fwd);
139 } else {
140 print_obj_safe(msg, fwd);
141 }
142 } else {
143 msg.append(" (the object itself)");
144 }
145 msg.append("\n");
146 }
147
148 if (level >= _safe_oop_fwd) {
149 oop fwd = (oop) ShenandoahBrooksPointer::get_raw_unchecked(obj);
150 oop fwd2 = (oop) ShenandoahBrooksPointer::get_raw_unchecked(fwd);
151 if (!oopDesc::unsafe_equals(fwd, fwd2)) {
152 msg.append("Second forwardee:\n");
153 print_obj_safe(msg, fwd2);
154 msg.append("\n");
155 }
156 }
157
158 report_vm_error(file, line, msg.buffer());
159 }
160
161 void ShenandoahAsserts::assert_in_heap(void* interior_loc, oop obj, const char *file, int line) {
162 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
163
164 if (!heap->is_in(obj)) {
165 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_heap failed",
166 "oop must point to a heap address",
167 file, line);
168 }
169 }
170
171 void ShenandoahAsserts::assert_correct(void* interior_loc, oop obj, const char* file, int line) {
172 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
173
174 // Step 1. Check that obj is correct.
175 // After this step, it is safe to call heap_region_containing().
176 if (!heap->is_in(obj)) {
177 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
178 "oop must point to a heap address",
179 file, line);
180 }
181
182 Klass* obj_klass = obj->klass_or_null();
183 if (obj_klass == NULL) {
184 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
185 "Object klass pointer should not be NULL",
186 file,line);
187 }
188
189 if (!Metaspace::contains(obj_klass)) {
190 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
191 "Object klass pointer must go to metaspace",
192 file,line);
193 }
194
195 oop fwd = oop(ShenandoahBrooksPointer::get_raw_unchecked(obj));
196
197 if (!oopDesc::unsafe_equals(obj, fwd)) {
198 // When Full GC moves the objects, we cannot trust fwdptrs. If we got here, it means something
199 // tries fwdptr manipulation when Full GC is running. The only exception is using the fwdptr
200 // that still points to the object itself.
201 if (heap->is_full_gc_move_in_progress()) {
202 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
203 "Non-trivial forwarding pointer during Full GC moves, probable bug.",
204 file, line);
205 }
206
207 // Step 2. Check that forwardee is correct
208 if (!heap->is_in(fwd)) {
209 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
210 "Forwardee must point to a heap address",
211 file, line);
212 }
213
214 if (obj_klass != fwd->klass()) {
215 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
216 "Forwardee klass disagrees with object class",
217 file, line);
218 }
219
220 // Step 3. Check that forwardee points to correct region
221 if (heap->heap_region_index_containing(fwd) == heap->heap_region_index_containing(obj)) {
222 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
223 "Non-trivial forwardee should in another region",
224 file, line);
225 }
226
227 // Step 4. Check for multiple forwardings
228 oop fwd2 = oop(ShenandoahBrooksPointer::get_raw_unchecked(fwd));
229 if (!oopDesc::unsafe_equals(fwd, fwd2)) {
230 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
231 "Multiple forwardings",
232 file, line);
233 }
234 }
235 }
236
237 void ShenandoahAsserts::assert_in_correct_region(void* interior_loc, oop obj, const char* file, int line) {
238 assert_correct(interior_loc, obj, file, line);
239
240 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
241 ShenandoahHeapRegion* r = heap->heap_region_containing(obj);
242 if (!r->is_active()) {
243 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
244 "Object must reside in active region",
245 file, line);
246 }
247
248 size_t alloc_size = obj->size() + ShenandoahBrooksPointer::word_size();
249 if (alloc_size > ShenandoahHeapRegion::humongous_threshold_words()) {
250 size_t idx = r->region_number();
251 size_t num_regions = ShenandoahHeapRegion::required_regions(alloc_size * HeapWordSize);
252 for (size_t i = idx; i < idx + num_regions; i++) {
253 ShenandoahHeapRegion* chain_reg = heap->get_region(i);
254 if (i == idx && !chain_reg->is_humongous_start()) {
255 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
256 "Object must reside in humongous start",
257 file, line);
258 }
259 if (i != idx && !chain_reg->is_humongous_continuation()) {
260 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
261 "Humongous continuation should be of proper size",
262 file, line);
263 }
264 }
265 }
266 }
267
268 void ShenandoahAsserts::assert_forwarded(void* interior_loc, oop obj, const char* file, int line) {
269 assert_correct(interior_loc, obj, file, line);
270 oop fwd = oop(ShenandoahBrooksPointer::get_raw_unchecked(obj));
271
272 if (oopDesc::unsafe_equals(obj, fwd)) {
273 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_forwarded failed",
274 "Object should be forwarded",
275 file, line);
276 }
277 }
278
279 void ShenandoahAsserts::assert_not_forwarded(void* interior_loc, oop obj, const char* file, int line) {
280 assert_correct(interior_loc, obj, file, line);
281 oop fwd = oop(ShenandoahBrooksPointer::get_raw_unchecked(obj));
282
283 if (!oopDesc::unsafe_equals(obj, fwd)) {
284 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_forwarded failed",
285 "Object should not be forwarded",
286 file, line);
287 }
288 }
289
290 void ShenandoahAsserts::assert_marked(void *interior_loc, oop obj, const char *file, int line) {
291 assert_correct(interior_loc, obj, file, line);
292
293 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
294 if (!heap->marking_context()->is_marked(obj)) {
295 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_marked failed",
296 "Object should be marked",
297 file, line);
298 }
299 }
300
301 void ShenandoahAsserts::assert_in_cset(void* interior_loc, oop obj, const char* file, int line) {
302 assert_correct(interior_loc, obj, file, line);
303
304 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
305 if (!heap->in_collection_set(obj)) {
306 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_in_cset failed",
307 "Object should be in collection set",
308 file, line);
309 }
310 }
311
312 void ShenandoahAsserts::assert_not_in_cset(void* interior_loc, oop obj, const char* file, int line) {
313 assert_correct(interior_loc, obj, file, line);
314
315 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
316 if (heap->in_collection_set(obj)) {
317 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_in_cset failed",
318 "Object should not be in collection set",
319 file, line);
320 }
321 }
322
323 void ShenandoahAsserts::assert_not_in_cset_loc(void* interior_loc, const char* file, int line) {
324 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
325 if (heap->in_collection_set(interior_loc)) {
326 print_failure(_safe_unknown, NULL, interior_loc, NULL, "Shenandoah assert_not_in_cset_loc failed",
327 "Interior location should not be in collection set",
328 file, line);
329 }
330 }
331
332 void ShenandoahAsserts::print_rp_failure(const char *label, BoolObjectClosure* actual,
333 const char *file, int line) {
334 ShenandoahMessageBuffer msg("%s\n", label);
335 msg.append(" Actual: " PTR_FORMAT "\n", p2i(actual));
336 report_vm_error(file, line, msg.buffer());
337 }
338
339 void ShenandoahAsserts::assert_rp_isalive_not_installed(const char *file, int line) {
340 ShenandoahHeap* heap = ShenandoahHeap::heap();
341 ReferenceProcessor* rp = heap->ref_processor();
342 if (rp->is_alive_non_header() != NULL) {
343 print_rp_failure("Shenandoah assert_rp_isalive_not_installed failed", rp->is_alive_non_header(),
344 file, line);
345 }
346 }
347
348 void ShenandoahAsserts::assert_rp_isalive_installed(const char *file, int line) {
349 ShenandoahHeap* heap = ShenandoahHeap::heap();
350 ReferenceProcessor* rp = heap->ref_processor();
351 if (rp->is_alive_non_header() == NULL) {
352 print_rp_failure("Shenandoah assert_rp_isalive_installed failed", rp->is_alive_non_header(),
353 file, line);
354 }
355 }