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/shenandoahForwarding.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 stringStream mw_ss;
62 obj->mark()->print_on(&mw_ss);
63
64 ShenandoahMarkingContext* const ctx = heap->marking_context();
65
66 msg.append(" " PTR_FORMAT " - klass " PTR_FORMAT " %s\n", p2i(obj), p2i(obj->klass()), obj->klass()->external_name());
67 msg.append(" %3s allocated after mark start\n", ctx->allocated_after_mark_start((HeapWord *) obj) ? "" : "not");
68 msg.append(" %3s marked \n", ctx->is_marked(obj) ? "" : "not");
69 msg.append(" %3s in collection set\n", heap->in_collection_set(obj) ? "" : "not");
70 msg.append(" mark:%s\n", mw_ss.as_string());
71 msg.append(" region: %s", ss.as_string());
72 }
73
74 void ShenandoahAsserts::print_non_obj(ShenandoahMessageBuffer& msg, void* loc) {
75 ShenandoahHeap* heap = ShenandoahHeap::heap();
76 if (heap->is_in(loc)) {
77 msg.append(" inside Java heap\n");
78 ShenandoahHeapRegion *r = heap->heap_region_containing(loc);
79 stringStream ss;
80 r->print_on(&ss);
81
82 msg.append(" %3s in collection set\n", heap->in_collection_set(loc) ? "" : "not");
83 msg.append(" region: %s", ss.as_string());
84 } else {
85 msg.append(" outside of Java heap\n");
86 stringStream ss;
87 os::print_location(&ss, (intptr_t) loc, false);
88 msg.append(" %s", ss.as_string());
89 }
90 }
91
92 void ShenandoahAsserts::print_obj_safe(ShenandoahMessageBuffer& msg, void* loc) {
93 ShenandoahHeap* heap = ShenandoahHeap::heap();
94 msg.append(" " PTR_FORMAT " - safe print, no details\n", p2i(loc));
95 if (heap->is_in(loc)) {
96 ShenandoahHeapRegion* r = heap->heap_region_containing(loc);
97 if (r != NULL) {
98 stringStream ss;
99 r->print_on(&ss);
100 msg.append(" region: %s", ss.as_string());
101 print_raw_memory(msg, loc);
102 }
103 }
104 }
105
106 void ShenandoahAsserts::print_failure(SafeLevel level, oop obj, void* interior_loc, oop loc,
107 const char* phase, const char* label,
108 const char* file, int line) {
109 ShenandoahHeap* heap = ShenandoahHeap::heap();
110 ResourceMark rm;
111
112 bool loc_in_heap = (loc != NULL && heap->is_in(loc));
113
114 ShenandoahMessageBuffer msg("%s; %s\n\n", phase, label);
115
116 msg.append("Referenced from:\n");
117 if (interior_loc != NULL) {
118 msg.append(" interior location: " PTR_FORMAT "\n", p2i(interior_loc));
119 if (loc_in_heap) {
120 print_obj(msg, loc);
121 } else {
122 print_non_obj(msg, interior_loc);
123 }
124 } else {
125 msg.append(" no interior location recorded (probably a plain heap scan, or detached oop)\n");
126 }
127 msg.append("\n");
128
129 msg.append("Object:\n");
130 if (level >= _safe_oop) {
131 print_obj(msg, obj);
132 } else {
133 print_obj_safe(msg, obj);
134 }
135 msg.append("\n");
136
137 if (level >= _safe_oop) {
138 oop fwd = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
139 msg.append("Forwardee:\n");
140 if (obj != fwd) {
141 if (level >= _safe_oop_fwd) {
142 print_obj(msg, fwd);
143 } else {
144 print_obj_safe(msg, fwd);
145 }
146 } else {
147 msg.append(" (the object itself)");
148 }
149 msg.append("\n");
150 }
151
152 if (level >= _safe_oop_fwd) {
153 oop fwd = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
154 oop fwd2 = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(fwd);
155 if (fwd != fwd2) {
156 msg.append("Second forwardee:\n");
157 print_obj_safe(msg, fwd2);
158 msg.append("\n");
159 }
160 }
161
162 report_vm_error(file, line, msg.buffer());
163 }
164
165 void ShenandoahAsserts::assert_in_heap(void* interior_loc, oop obj, const char *file, int line) {
166 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
167
168 if (!heap->is_in(obj)) {
169 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_heap failed",
170 "oop must point to a heap address",
171 file, line);
172 }
173 }
174
175 void ShenandoahAsserts::assert_correct(void* interior_loc, oop obj, const char* file, int line) {
176 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
177
178 // Step 1. Check that obj is correct.
179 // After this step, it is safe to call heap_region_containing().
180 if (!heap->is_in(obj)) {
181 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
182 "oop must point to a heap address",
183 file, line);
184 }
185
186 Klass* obj_klass = obj->klass_or_null();
187 if (obj_klass == NULL) {
188 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
189 "Object klass pointer should not be NULL",
190 file,line);
191 }
192
193 if (!Metaspace::contains(obj_klass)) {
194 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
195 "Object klass pointer must go to metaspace",
196 file,line);
197 }
198
199 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
200
201 if (obj != fwd) {
202 // When Full GC moves the objects, we cannot trust fwdptrs. If we got here, it means something
203 // tries fwdptr manipulation when Full GC is running. The only exception is using the fwdptr
204 // that still points to the object itself.
205 if (heap->is_full_gc_move_in_progress()) {
206 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
207 "Non-trivial forwarding pointer during Full GC moves, probable bug.",
208 file, line);
209 }
210
211 // Step 2. Check that forwardee is correct
212 if (!heap->is_in(fwd)) {
213 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
214 "Forwardee must point to a heap address",
215 file, line);
216 }
217
218 if (obj_klass != fwd->klass()) {
219 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
220 "Forwardee klass disagrees with object class",
221 file, line);
222 }
223
224 // Step 3. Check that forwardee points to correct region
225 if (heap->heap_region_index_containing(fwd) == heap->heap_region_index_containing(obj)) {
226 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
227 "Non-trivial forwardee should in another region",
228 file, line);
229 }
230
231 // Step 4. Check for multiple forwardings
232 oop fwd2 = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(fwd));
233 if (fwd != fwd2) {
234 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
235 "Multiple forwardings",
236 file, line);
237 }
238 }
239 }
240
241 void ShenandoahAsserts::assert_in_correct_region(void* interior_loc, oop obj, const char* file, int line) {
242 assert_correct(interior_loc, obj, file, line);
243
244 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
245 ShenandoahHeapRegion* r = heap->heap_region_containing(obj);
246 if (!r->is_active()) {
247 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
248 "Object must reside in active region",
249 file, line);
250 }
251
252 size_t alloc_size = obj->size();
253 if (alloc_size > ShenandoahHeapRegion::humongous_threshold_words()) {
254 size_t idx = r->region_number();
255 size_t num_regions = ShenandoahHeapRegion::required_regions(alloc_size * HeapWordSize);
256 for (size_t i = idx; i < idx + num_regions; i++) {
257 ShenandoahHeapRegion* chain_reg = heap->get_region(i);
258 if (i == idx && !chain_reg->is_humongous_start()) {
259 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
260 "Object must reside in humongous start",
261 file, line);
262 }
263 if (i != idx && !chain_reg->is_humongous_continuation()) {
264 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
265 "Humongous continuation should be of proper size",
266 file, line);
267 }
268 }
269 }
270 }
271
272 void ShenandoahAsserts::assert_forwarded(void* interior_loc, oop obj, const char* file, int line) {
273 assert_correct(interior_loc, obj, file, line);
274 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
275
276 if (obj == fwd) {
277 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_forwarded failed",
278 "Object should be forwarded",
279 file, line);
280 }
281 }
282
283 void ShenandoahAsserts::assert_not_forwarded(void* interior_loc, oop obj, const char* file, int line) {
284 assert_correct(interior_loc, obj, file, line);
285 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
286
287 if (obj != fwd) {
288 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_forwarded failed",
289 "Object should not be forwarded",
290 file, line);
291 }
292 }
293
294 void ShenandoahAsserts::assert_marked(void *interior_loc, oop obj, const char *file, int line) {
295 assert_correct(interior_loc, obj, file, line);
296
297 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
298 if (!heap->marking_context()->is_marked(obj)) {
299 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_marked failed",
300 "Object should be marked",
301 file, line);
302 }
303 }
304
305 void ShenandoahAsserts::assert_in_cset(void* interior_loc, oop obj, const char* file, int line) {
306 assert_correct(interior_loc, obj, file, line);
307
308 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
309 if (!heap->in_collection_set(obj)) {
310 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_in_cset failed",
311 "Object should be in collection set",
312 file, line);
313 }
314 }
315
316 void ShenandoahAsserts::assert_not_in_cset(void* interior_loc, oop obj, const char* file, int line) {
317 assert_correct(interior_loc, obj, file, line);
318
319 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
320 if (heap->in_collection_set(obj)) {
321 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_in_cset failed",
322 "Object should not be in collection set",
323 file, line);
324 }
325 }
326
327 void ShenandoahAsserts::assert_not_in_cset_loc(void* interior_loc, const char* file, int line) {
328 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
329 if (heap->in_collection_set(interior_loc)) {
330 print_failure(_safe_unknown, NULL, interior_loc, NULL, "Shenandoah assert_not_in_cset_loc failed",
331 "Interior location should not be in collection set",
332 file, line);
333 }
334 }
335
336 void ShenandoahAsserts::print_rp_failure(const char *label, BoolObjectClosure* actual,
337 const char *file, int line) {
338 ShenandoahMessageBuffer msg("%s\n", label);
339 msg.append(" Actual: " PTR_FORMAT "\n", p2i(actual));
340 report_vm_error(file, line, msg.buffer());
341 }
342
343 void ShenandoahAsserts::assert_rp_isalive_not_installed(const char *file, int line) {
344 ShenandoahHeap* heap = ShenandoahHeap::heap();
345 ReferenceProcessor* rp = heap->ref_processor();
346 if (rp->is_alive_non_header() != NULL) {
347 print_rp_failure("Shenandoah assert_rp_isalive_not_installed failed", rp->is_alive_non_header(),
348 file, line);
349 }
350 }
351
352 void ShenandoahAsserts::assert_rp_isalive_installed(const char *file, int line) {
353 ShenandoahHeap* heap = ShenandoahHeap::heap();
354 ReferenceProcessor* rp = heap->ref_processor();
355 if (rp->is_alive_non_header() == NULL) {
356 print_rp_failure("Shenandoah assert_rp_isalive_installed failed", rp->is_alive_non_header(),
357 file, line);
358 }
359 }