1 /*
2 * Copyright (c) 2015, 2018, 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 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
26
27 #include "gc/shared/barrierSet.hpp"
28 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
29 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp"
30 #include "gc/shenandoah/shenandoahForwarding.inline.hpp"
31 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
32 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
33 #include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
34 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
35 #include "memory/iterator.inline.hpp"
36 #include "oops/oop.inline.hpp"
37
38 inline oop ShenandoahBarrierSet::resolve_forwarded_not_null(oop p) {
39 return ShenandoahForwarding::get_forwardee(p);
40 }
41
42 inline oop ShenandoahBarrierSet::resolve_forwarded(oop p) {
43 if (((HeapWord*) p) != NULL) {
44 return resolve_forwarded_not_null(p);
45 } else {
46 return p;
47 }
48 }
49
50 inline void ShenandoahBarrierSet::enqueue(oop obj) {
51 shenandoah_assert_not_forwarded_if(NULL, obj, _heap->is_concurrent_traversal_in_progress());
52 assert(_satb_mark_queue_set.is_active(), "only get here when SATB active");
53
54 // Filter marked objects before hitting the SATB queues. The same predicate would
55 // be used by SATBMQ::filter to eliminate already marked objects downstream, but
56 // filtering here helps to avoid wasteful SATB queueing work to begin with.
57 if (!_heap->requires_marking(obj)) return;
58
59 Thread* thr = Thread::current();
60 if (thr->is_Java_thread()) {
61 ShenandoahThreadLocalData::satb_mark_queue(thr).enqueue_known_active(obj);
62 } else {
63 MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag);
64 _satb_mark_queue_set.shared_satb_queue()->enqueue_known_active(obj);
65 }
66 }
67
68 template <DecoratorSet decorators, typename T>
69 inline void ShenandoahBarrierSet::satb_barrier(T *field) {
70 if (HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value ||
71 HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
72 return;
73 }
74 if (ShenandoahSATBBarrier && _heap->is_concurrent_mark_in_progress()) {
75 T heap_oop = RawAccess<>::oop_load(field);
76 if (!CompressedOops::is_null(heap_oop)) {
77 enqueue(CompressedOops::decode(heap_oop));
78 }
79 }
80 }
81
82 inline void ShenandoahBarrierSet::satb_enqueue(oop value) {
83 assert(value != NULL, "checked before");
84 if (ShenandoahSATBBarrier && _heap->is_concurrent_mark_in_progress()) {
85 enqueue(value);
86 }
87 }
88
89 inline void ShenandoahBarrierSet::storeval_barrier(oop obj) {
90 if (obj != NULL && ShenandoahStoreValEnqueueBarrier && _heap->is_concurrent_traversal_in_progress()) {
91 enqueue(obj);
92 }
93 }
94
95 inline void ShenandoahBarrierSet::keep_alive_barrier(oop value) {
96 assert(value != NULL, "checked before");
97 if (ShenandoahKeepAliveBarrier && _heap->is_concurrent_mark_in_progress()) {
98 enqueue(value);
99 }
100 }
101
102 inline void ShenandoahBarrierSet::keep_alive_if_weak(DecoratorSet decorators, oop value) {
103 assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
104 const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
105 const bool peek = (decorators & AS_NO_KEEPALIVE) != 0;
106 if (!peek && !on_strong_oop_ref) {
107 keep_alive_barrier(value);
108 }
109 }
110
111 template <DecoratorSet decorators>
112 inline void ShenandoahBarrierSet::keep_alive_if_weak(oop value) {
113 assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
114 if (!HasDecorator<decorators, ON_STRONG_OOP_REF>::value &&
115 !HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
116 keep_alive_barrier(value);
117 }
118 }
119
120 template <DecoratorSet decorators, typename BarrierSetT>
121 template <typename T>
122 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_not_in_heap(T* addr) {
123 oop value = Raw::oop_load_not_in_heap(addr);
124 if (value != NULL) {
125 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
126 value = bs->load_reference_barrier_not_null(value);
127 bs->keep_alive_if_weak<decorators>(value);
128 }
129 return value;
130 }
131
132 template <DecoratorSet decorators, typename BarrierSetT>
133 template <typename T>
134 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap(T* addr) {
135 oop value = Raw::oop_load_in_heap(addr);
136 if (value != NULL) {
137 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
138 value = bs->load_reference_barrier_not_null(value);
139 bs->keep_alive_if_weak<decorators>(value);
140 }
141 return value;
142 }
143
144 template <DecoratorSet decorators, typename BarrierSetT>
145 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap_at(oop base, ptrdiff_t offset) {
146 oop value = Raw::oop_load_in_heap_at(base, offset);
147 if (value != NULL) {
148 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
149 value = bs->load_reference_barrier_not_null(value);
150 bs->keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset),
151 value);
152 }
153 return value;
154 }
155
156 template <DecoratorSet decorators, typename BarrierSetT>
157 template <typename T>
158 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_not_in_heap(T* addr, oop value) {
159 shenandoah_assert_marked_if(NULL, value, !CompressedOops::is_null(value) && ShenandoahHeap::heap()->is_evacuation_in_progress());
160 ShenandoahBarrierSet* const bs = ShenandoahBarrierSet::barrier_set();
161 bs->storeval_barrier(value);
162 bs->satb_barrier<decorators>(addr);
163 Raw::oop_store(addr, value);
164 }
165
166 template <DecoratorSet decorators, typename BarrierSetT>
167 template <typename T>
168 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap(T* addr, oop value) {
169 shenandoah_assert_not_in_cset_loc_except(addr, ShenandoahHeap::heap()->cancelled_gc());
170 shenandoah_assert_not_forwarded_except (addr, value, value == NULL || ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahHeap::heap()->is_concurrent_mark_in_progress());
171 shenandoah_assert_not_in_cset_except (addr, value, value == NULL || ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahHeap::heap()->is_concurrent_mark_in_progress());
172
173 oop_store_not_in_heap(addr, value);
174 }
175
176 template <DecoratorSet decorators, typename BarrierSetT>
177 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
178 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);
179 }
180
181 template <DecoratorSet decorators, typename BarrierSetT>
182 template <typename T>
183 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
184 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
185 bs->storeval_barrier(new_value);
186
187 oop res;
188 oop expected = compare_value;
189 do {
190 compare_value = expected;
191 res = Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
192 expected = res;
193 } while (compare_value != expected && resolve_forwarded(compare_value) == resolve_forwarded(expected));
194
195 // Note: We don't need a keep-alive-barrier here. We already enqueue any loaded reference for SATB anyway,
196 // because it must be the previous value.
197 if (res != NULL) {
198 res = ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(res);
199 bs->satb_enqueue(res);
200 }
201 return res;
202 }
203
204 template <DecoratorSet decorators, typename BarrierSetT>
205 template <typename T>
206 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
207 return oop_atomic_cmpxchg_not_in_heap(new_value, addr, compare_value);
208 }
209
210 template <DecoratorSet decorators, typename BarrierSetT>
211 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
212 return oop_atomic_cmpxchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value);
213 }
214
215 template <DecoratorSet decorators, typename BarrierSetT>
216 template <typename T>
217 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
218 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
219 bs->storeval_barrier(new_value);
220
221 oop previous = Raw::oop_atomic_xchg(new_value, addr);
222
223 // Note: We don't need a keep-alive-barrier here. We already enqueue any loaded reference for SATB anyway,
224 // because it must be the previous value.
225 if (previous != NULL) {
226 previous = ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(previous);
227 bs->satb_enqueue(previous);
228 }
229 return previous;
230 }
231
232 template <DecoratorSet decorators, typename BarrierSetT>
233 template <typename T>
234 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap(oop new_value, T* addr) {
235 return oop_atomic_xchg_in_heap_impl(new_value, addr);
236 }
237
238 template <DecoratorSet decorators, typename BarrierSetT>
239 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
240 return oop_atomic_xchg_in_heap_impl(new_value, AccessInternal::oop_field_addr<decorators>(base, offset));
241 }
242
243 // Clone barrier support
244 template <DecoratorSet decorators, typename BarrierSetT>
245 void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::clone_in_heap(oop src, oop dst, size_t size) {
246 if (ShenandoahCloneBarrier) {
247 ShenandoahBarrierSet::barrier_set()->clone_barrier_runtime(src);
248 }
249 Raw::clone(src, dst, size);
250 }
251
252 template <DecoratorSet decorators, typename BarrierSetT>
253 template <typename T>
254 bool ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
255 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
256 size_t length) {
257 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
258 bs->arraycopy_pre(arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw),
259 arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw),
260 length);
261 return Raw::oop_arraycopy_in_heap(src_obj, src_offset_in_bytes, src_raw, dst_obj, dst_offset_in_bytes, dst_raw, length);
262 }
263
264 template <class T, bool HAS_FWD, bool EVAC, bool ENQUEUE>
265 void ShenandoahBarrierSet::arraycopy_work(T* src, size_t count) {
266 Thread* thread = Thread::current();
267 ShenandoahSATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
268 ShenandoahMarkingContext* ctx = _heap->marking_context();
269 const ShenandoahCollectionSet* const cset = _heap->collection_set();
270 T* end = src + count;
271 for (T* elem_ptr = src; elem_ptr < end; elem_ptr++) {
272 T o = RawAccess<>::oop_load(elem_ptr);
273 if (!CompressedOops::is_null(o)) {
274 oop obj = CompressedOops::decode_not_null(o);
275 if (HAS_FWD && cset->is_in((HeapWord *) obj)) {
276 assert(_heap->has_forwarded_objects(), "only get here with forwarded objects");
277 oop fwd = resolve_forwarded_not_null(obj);
278 if (EVAC && obj == fwd) {
279 fwd = _heap->evacuate_object(obj, thread);
280 }
281 assert(obj != fwd || _heap->cancelled_gc(), "must be forwarded");
282 oop witness = ShenandoahHeap::cas_oop(fwd, elem_ptr, o);
283 obj = fwd;
284 }
285 if (ENQUEUE && !ctx->is_marked(obj)) {
286 queue.enqueue_known_active(obj);
287 }
288 }
289 }
290 }
291
292 template <class T>
293 void ShenandoahBarrierSet::arraycopy_pre_work(T* src, T* dst, size_t count) {
294 if (_heap->is_concurrent_mark_in_progress()) {
295 if (_heap->has_forwarded_objects()) {
296 arraycopy_work<T, true, false, true>(dst, count);
297 } else {
298 arraycopy_work<T, false, false, true>(dst, count);
299 }
300 }
301
302 arraycopy_update_impl(src, count);
303 }
304
305 void ShenandoahBarrierSet::arraycopy_pre(oop* src, oop* dst, size_t count) {
306 arraycopy_pre_work(src, dst, count);
307 }
308
309 void ShenandoahBarrierSet::arraycopy_pre(narrowOop* src, narrowOop* dst, size_t count) {
310 arraycopy_pre_work(src, dst, count);
311 }
312
313 template <class T>
314 void ShenandoahBarrierSet::arraycopy_update_impl(T* src, size_t count) {
315 if (_heap->is_evacuation_in_progress()) {
316 ShenandoahEvacOOMScope oom_evac;
317 arraycopy_work<T, true, true, false>(src, count);
318 } else if (_heap->is_concurrent_traversal_in_progress()){
319 ShenandoahEvacOOMScope oom_evac;
320 arraycopy_work<T, true, true, true>(src, count);
321 } else if (_heap->has_forwarded_objects()) {
322 arraycopy_work<T, true, false, false>(src, count);
323 }
324 }
325
326 void ShenandoahBarrierSet::arraycopy_update(oop* src, size_t count) {
327 arraycopy_update_impl(src, count);
328 }
329
330 void ShenandoahBarrierSet::arraycopy_update(narrowOop* src, size_t count) {
331 arraycopy_update_impl(src, count);
332 }
333
334 #endif //SHARE_VM_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP