1 /*
2 * Copyright (c) 2018, 2019, Red Hat, Inc. 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
27 #include "gc/shenandoah/shenandoahAsserts.hpp"
28 #include "gc/shenandoah/shenandoahForwarding.hpp"
29 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
30 #include "gc/shenandoah/shenandoahHeapRegionSet.inline.hpp"
31 #include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
32 #include "gc/shenandoah/shenandoahTraversalGC.hpp"
33 #include "gc/shenandoah/shenandoahUtils.hpp"
34 #include "memory/resourceArea.hpp"
35
36 void print_raw_memory(ShenandoahMessageBuffer &msg, void* loc) {
37 // Be extra safe. Only access data that is guaranteed to be safe:
38 // should be in heap, in known committed region, within that region.
39
40 ShenandoahHeap* heap = ShenandoahHeap::heap();
41 if (!heap->is_in(loc)) return;
42
43 ShenandoahHeapRegion* r = heap->heap_region_containing(loc);
44 if (r != NULL && r->is_committed()) {
45 address start = MAX2((address) r->bottom(), (address) loc - 32);
46 address end = MIN2((address) r->end(), (address) loc + 128);
47 if (start >= end) return;
48
49 stringStream ss;
50 os::print_hex_dump(&ss, start, end, 4);
51 msg.append("\n");
52 msg.append("Raw heap memory:\n%s", ss.as_string());
53 }
54 }
55
56 void ShenandoahAsserts::print_obj(ShenandoahMessageBuffer& msg, oop obj) {
57 ShenandoahHeap* heap = ShenandoahHeap::heap();
58 ShenandoahHeapRegion *r = heap->heap_region_containing(obj);
59
60 ResourceMark rm;
61 stringStream ss;
62 r->print_on(&ss);
63
64 stringStream mw_ss;
65 obj->mark().print_on(&mw_ss);
66
67 ShenandoahMarkingContext* const ctx = heap->marking_context();
68
69 msg.append(" " PTR_FORMAT " - klass " PTR_FORMAT " %s\n", p2i(obj), p2i(obj->klass()), obj->klass()->external_name());
70 msg.append(" %3s allocated after mark start\n", ctx->allocated_after_mark_start((HeapWord *) obj) ? "" : "not");
71 msg.append(" %3s marked \n", ctx->is_marked(obj) ? "" : "not");
72 msg.append(" %3s in collection set\n", heap->in_collection_set(obj) ? "" : "not");
73 if (heap->traversal_gc() != NULL) {
74 msg.append(" %3s in traversal set\n", heap->traversal_gc()->traversal_set()->is_in((HeapWord*) obj) ? "" : "not");
75 }
76 msg.append(" mark:%s\n", mw_ss.as_string());
77 msg.append(" region: %s", ss.as_string());
78 }
79
80 void ShenandoahAsserts::print_non_obj(ShenandoahMessageBuffer& msg, void* loc) {
81 ShenandoahHeap* heap = ShenandoahHeap::heap();
82 if (heap->is_in(loc)) {
83 msg.append(" inside Java heap\n");
84 ShenandoahHeapRegion *r = heap->heap_region_containing(loc);
85 stringStream ss;
86 r->print_on(&ss);
87
88 msg.append(" %3s in collection set\n", heap->in_collection_set(loc) ? "" : "not");
89 msg.append(" region: %s", ss.as_string());
90 } else {
91 msg.append(" outside of Java heap\n");
92 stringStream ss;
93 os::print_location(&ss, (intptr_t) loc, false);
94 msg.append(" %s", ss.as_string());
95 }
96 }
97
98 void ShenandoahAsserts::print_obj_safe(ShenandoahMessageBuffer& msg, void* loc) {
99 ShenandoahHeap* heap = ShenandoahHeap::heap();
100 msg.append(" " PTR_FORMAT " - safe print, no details\n", p2i(loc));
101 if (heap->is_in(loc)) {
102 ShenandoahHeapRegion* r = heap->heap_region_containing(loc);
103 if (r != NULL) {
104 stringStream ss;
105 r->print_on(&ss);
106 msg.append(" region: %s", ss.as_string());
107 print_raw_memory(msg, loc);
108 }
109 }
110 }
111
112 void ShenandoahAsserts::print_failure(SafeLevel level, oop obj, void* interior_loc, oop loc,
113 const char* phase, const char* label,
114 const char* file, int line) {
115 ShenandoahHeap* heap = ShenandoahHeap::heap();
116 ResourceMark rm;
117
118 bool loc_in_heap = (loc != NULL && heap->is_in(loc));
119
120 ShenandoahMessageBuffer msg("%s; %s\n\n", phase, label);
121
122 msg.append("Referenced from:\n");
123 if (interior_loc != NULL) {
124 msg.append(" interior location: " PTR_FORMAT "\n", p2i(interior_loc));
125 if (loc_in_heap) {
126 print_obj(msg, loc);
127 } else {
128 print_non_obj(msg, interior_loc);
129 }
130 } else {
131 msg.append(" no interior location recorded (probably a plain heap scan, or detached oop)\n");
132 }
133 msg.append("\n");
134
135 msg.append("Object:\n");
136 if (level >= _safe_oop) {
137 print_obj(msg, obj);
138 } else {
139 print_obj_safe(msg, obj);
140 }
141 msg.append("\n");
142
143 if (level >= _safe_oop) {
144 oop fwd = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
145 msg.append("Forwardee:\n");
146 if (obj != fwd) {
147 if (level >= _safe_oop_fwd) {
148 print_obj(msg, fwd);
149 } else {
150 print_obj_safe(msg, fwd);
151 }
152 } else {
153 msg.append(" (the object itself)");
154 }
155 msg.append("\n");
156 }
157
158 if (level >= _safe_oop_fwd) {
159 oop fwd = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(obj);
160 oop fwd2 = (oop) ShenandoahForwarding::get_forwardee_raw_unchecked(fwd);
161 if (fwd != fwd2) {
162 msg.append("Second forwardee:\n");
163 print_obj_safe(msg, fwd2);
164 msg.append("\n");
165 }
166 }
167
168 report_vm_error(file, line, msg.buffer());
169 }
170
171 void ShenandoahAsserts::assert_in_heap(void* interior_loc, oop obj, const char *file, int line) {
172 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
173
174 if (!heap->is_in(obj)) {
175 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_heap failed",
176 "oop must point to a heap address",
177 file, line);
178 }
179 }
180
181 void ShenandoahAsserts::assert_correct(void* interior_loc, oop obj, const char* file, int line) {
182 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
183
184 // Step 1. Check that obj is correct.
185 // After this step, it is safe to call heap_region_containing().
186 if (!heap->is_in(obj)) {
187 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
188 "oop must point to a heap address",
189 file, line);
190 }
191
192 Klass* obj_klass = obj->klass_or_null();
193 if (obj_klass == NULL) {
194 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
195 "Object klass pointer should not be NULL",
196 file,line);
197 }
198
199 if (!Metaspace::contains(obj_klass)) {
200 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
201 "Object klass pointer must go to metaspace",
202 file,line);
203 }
204
205 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
206
207 if (obj != fwd) {
208 // When Full GC moves the objects, we cannot trust fwdptrs. If we got here, it means something
209 // tries fwdptr manipulation when Full GC is running. The only exception is using the fwdptr
210 // that still points to the object itself.
211 if (heap->is_full_gc_move_in_progress()) {
212 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
213 "Non-trivial forwarding pointer during Full GC moves, probable bug.",
214 file, line);
215 }
216
217 // Step 2. Check that forwardee is correct
218 if (!heap->is_in(fwd)) {
219 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
220 "Forwardee must point to a heap address",
221 file, line);
222 }
223
224 if (obj_klass != fwd->klass()) {
225 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
226 "Forwardee klass disagrees with object class",
227 file, line);
228 }
229
230 // Step 3. Check that forwardee points to correct region
231 if (heap->heap_region_index_containing(fwd) == heap->heap_region_index_containing(obj)) {
232 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
233 "Non-trivial forwardee should in another region",
234 file, line);
235 }
236
237 // Step 4. Check for multiple forwardings
238 oop fwd2 = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(fwd));
239 if (fwd != fwd2) {
240 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_correct failed",
241 "Multiple forwardings",
242 file, line);
243 }
244 }
245 }
246
247 void ShenandoahAsserts::assert_in_correct_region(void* interior_loc, oop obj, const char* file, int line) {
248 assert_correct(interior_loc, obj, file, line);
249
250 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
251 ShenandoahHeapRegion* r = heap->heap_region_containing(obj);
252 if (!r->is_active()) {
253 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
254 "Object must reside in active region",
255 file, line);
256 }
257
258 size_t alloc_size = obj->size();
259 if (alloc_size > ShenandoahHeapRegion::humongous_threshold_words()) {
260 size_t idx = r->region_number();
261 size_t num_regions = ShenandoahHeapRegion::required_regions(alloc_size * HeapWordSize);
262 for (size_t i = idx; i < idx + num_regions; i++) {
263 ShenandoahHeapRegion* chain_reg = heap->get_region(i);
264 if (i == idx && !chain_reg->is_humongous_start()) {
265 print_failure(_safe_unknown, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
266 "Object must reside in humongous start",
267 file, line);
268 }
269 if (i != idx && !chain_reg->is_humongous_continuation()) {
270 print_failure(_safe_oop, obj, interior_loc, NULL, "Shenandoah assert_in_correct_region failed",
271 "Humongous continuation should be of proper size",
272 file, line);
273 }
274 }
275 }
276 }
277
278 void ShenandoahAsserts::assert_forwarded(void* interior_loc, oop obj, const char* file, int line) {
279 assert_correct(interior_loc, obj, file, line);
280 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
281
282 if (obj == fwd) {
283 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_forwarded failed",
284 "Object should be forwarded",
285 file, line);
286 }
287 }
288
289 void ShenandoahAsserts::assert_not_forwarded(void* interior_loc, oop obj, const char* file, int line) {
290 assert_correct(interior_loc, obj, file, line);
291 oop fwd = oop(ShenandoahForwarding::get_forwardee_raw_unchecked(obj));
292
293 if (obj != fwd) {
294 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_forwarded failed",
295 "Object should not be forwarded",
296 file, line);
297 }
298 }
299
300 void ShenandoahAsserts::assert_marked(void *interior_loc, oop obj, const char *file, int line) {
301 assert_correct(interior_loc, obj, file, line);
302
303 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
304 if (!heap->marking_context()->is_marked(obj)) {
305 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_marked failed",
306 "Object should be marked",
307 file, line);
308 }
309 }
310
311 void ShenandoahAsserts::assert_in_cset(void* interior_loc, oop obj, const char* file, int line) {
312 assert_correct(interior_loc, obj, file, line);
313
314 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
315 if (!heap->in_collection_set(obj)) {
316 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_in_cset failed",
317 "Object should be in collection set",
318 file, line);
319 }
320 }
321
322 void ShenandoahAsserts::assert_not_in_cset(void* interior_loc, oop obj, const char* file, int line) {
323 assert_correct(interior_loc, obj, file, line);
324
325 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
326 if (heap->in_collection_set(obj)) {
327 print_failure(_safe_all, obj, interior_loc, NULL, "Shenandoah assert_not_in_cset failed",
328 "Object should not be in collection set",
329 file, line);
330 }
331 }
332
333 void ShenandoahAsserts::assert_not_in_cset_loc(void* interior_loc, const char* file, int line) {
334 ShenandoahHeap* heap = ShenandoahHeap::heap_no_check();
335 if (heap->in_collection_set(interior_loc)) {
336 print_failure(_safe_unknown, NULL, interior_loc, NULL, "Shenandoah assert_not_in_cset_loc failed",
337 "Interior location should not be in collection set",
338 file, line);
339 }
340 }
341
342 void ShenandoahAsserts::print_rp_failure(const char *label, BoolObjectClosure* actual,
343 const char *file, int line) {
344 ShenandoahMessageBuffer msg("%s\n", label);
345 msg.append(" Actual: " PTR_FORMAT "\n", p2i(actual));
346 report_vm_error(file, line, msg.buffer());
347 }
348
349 void ShenandoahAsserts::assert_rp_isalive_not_installed(const char *file, int line) {
350 ShenandoahHeap* heap = ShenandoahHeap::heap();
351 ReferenceProcessor* rp = heap->ref_processor();
352 if (rp->is_alive_non_header() != NULL) {
353 print_rp_failure("Shenandoah assert_rp_isalive_not_installed failed", rp->is_alive_non_header(),
354 file, line);
355 }
356 }
357
358 void ShenandoahAsserts::assert_rp_isalive_installed(const char *file, int line) {
359 ShenandoahHeap* heap = ShenandoahHeap::heap();
360 ReferenceProcessor* rp = heap->ref_processor();
361 if (rp->is_alive_non_header() == NULL) {
362 print_rp_failure("Shenandoah assert_rp_isalive_installed failed", rp->is_alive_non_header(),
363 file, line);
364 }
365 }
366
367 void ShenandoahAsserts::assert_locked_or_shenandoah_safepoint(Mutex* lock, const char* file, int line) {
368 if (ShenandoahSafepoint::is_at_shenandoah_safepoint()) {
369 return;
370 }
371
372 if (lock->owned_by_self()) {
373 return;
374 }
375
376 ShenandoahMessageBuffer msg("Must ba at a Shenandoah safepoint or held %s lock", lock->name());
377 report_vm_error(file, line, msg.buffer());
378 }