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