1 /*
2 * Copyright (c) 2015, 2020, 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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
27
28 #include "gc/shared/barrierSet.hpp"
29 #include "gc/shenandoah/shenandoahAsserts.hpp"
30 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
31 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp"
32 #include "gc/shenandoah/shenandoahForwarding.inline.hpp"
33 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
34 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
35 #include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
36 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
37 #include "memory/iterator.inline.hpp"
38 #include "oops/oop.inline.hpp"
39
40 inline oop ShenandoahBarrierSet::resolve_forwarded_not_null(oop p) {
41 return ShenandoahForwarding::get_forwardee(p);
42 }
43
44 inline oop ShenandoahBarrierSet::resolve_forwarded(oop p) {
45 if (p != NULL) {
46 return resolve_forwarded_not_null(p);
47 } else {
48 return p;
49 }
50 }
51
52 inline oop ShenandoahBarrierSet::resolve_forwarded_not_null_mutator(oop p) {
53 return ShenandoahForwarding::get_forwardee_mutator(p);
54 }
55
56 inline void ShenandoahBarrierSet::enqueue(oop obj) {
57 assert(_satb_mark_queue_set.is_active(), "only get here when SATB active");
58
59 // Filter marked objects before hitting the SATB queues. The same predicate would
60 // be used by SATBMQ::filter to eliminate already marked objects downstream, but
61 // filtering here helps to avoid wasteful SATB queueing work to begin with.
62 if (!_heap->requires_marking<false>(obj)) return;
63
64 ShenandoahThreadLocalData::satb_mark_queue(Thread::current()).enqueue_known_active(obj);
65 }
66
67 template <DecoratorSet decorators, typename T>
68 inline void ShenandoahBarrierSet::satb_barrier(T *field) {
69 if (HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value ||
70 HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
71 return;
72 }
73 if (ShenandoahSATBBarrier && _heap->is_concurrent_mark_in_progress()) {
74 T heap_oop = RawAccess<>::oop_load(field);
75 if (!CompressedOops::is_null(heap_oop)) {
76 enqueue(CompressedOops::decode(heap_oop));
77 }
78 }
79 }
80
81 inline void ShenandoahBarrierSet::satb_enqueue(oop value) {
82 assert(value != NULL, "checked before");
83 if (ShenandoahSATBBarrier && _heap->is_concurrent_mark_in_progress()) {
84 enqueue(value);
85 }
86 }
87
88 inline void ShenandoahBarrierSet::storeval_barrier(oop obj) {
89 if (obj != NULL && ShenandoahStoreValEnqueueBarrier) {
90 enqueue(obj);
91 }
92 }
93
94 inline void ShenandoahBarrierSet::keep_alive_if_weak(DecoratorSet decorators, oop value) {
95 assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
96 const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
97 const bool peek = (decorators & AS_NO_KEEPALIVE) != 0;
98 if (!peek && !on_strong_oop_ref) {
99 satb_enqueue(value);
100 }
101 }
102
103 template <DecoratorSet decorators>
104 inline void ShenandoahBarrierSet::keep_alive_if_weak(oop value) {
105 assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
106 if (!HasDecorator<decorators, ON_STRONG_OOP_REF>::value &&
107 !HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
108 satb_enqueue(value);
109 }
110 }
111
112 template <DecoratorSet decorators, typename BarrierSetT>
113 template <typename T>
114 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_not_in_heap(T* addr) {
115 oop value = Raw::oop_load_not_in_heap(addr);
116 if (value != NULL) {
117 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
118 value = bs->load_reference_barrier_native(value, addr);
119 if (value != NULL) {
120 bs->keep_alive_if_weak<decorators>(value);
121 }
122 }
123 return value;
124 }
125
126 template <DecoratorSet decorators, typename BarrierSetT>
127 template <typename T>
128 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap(T* addr) {
129 oop value = Raw::oop_load_in_heap(addr);
130 if (value != NULL) {
131 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
132 value = bs->load_reference_barrier_not_null(value);
133 bs->keep_alive_if_weak<decorators>(value);
134 }
135 return value;
136 }
137
138 template <DecoratorSet decorators, typename BarrierSetT>
139 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap_at(oop base, ptrdiff_t offset) {
140 oop value = Raw::oop_load_in_heap_at(base, offset);
141 if (value != NULL) {
142 ShenandoahBarrierSet *const bs = ShenandoahBarrierSet::barrier_set();
143 value = bs->load_reference_barrier_not_null(value);
144 bs->keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset),
145 value);
146 }
147 return value;
148 }
149
150 template <DecoratorSet decorators, typename BarrierSetT>
151 template <typename T>
152 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_not_in_heap(T* addr, oop value) {
153 shenandoah_assert_marked_if(NULL, value, !CompressedOops::is_null(value) && ShenandoahHeap::heap()->is_evacuation_in_progress());
154 ShenandoahBarrierSet* const bs = ShenandoahBarrierSet::barrier_set();
155 bs->storeval_barrier(value);
156 bs->satb_barrier<decorators>(addr);
157 Raw::oop_store(addr, value);
158 }
159
160 template <DecoratorSet decorators, typename BarrierSetT>
161 template <typename T>
162 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap(T* addr, oop value) {
163 shenandoah_assert_not_in_cset_loc_except(addr, ShenandoahHeap::heap()->cancelled_gc());
164 shenandoah_assert_not_forwarded_except (addr, value, value == NULL || ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahHeap::heap()->is_concurrent_mark_in_progress());
165 shenandoah_assert_not_in_cset_except (addr, value, value == NULL || ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahHeap::heap()->is_concurrent_mark_in_progress());
166
167 oop_store_not_in_heap(addr, value);
168 }
169
170 template <DecoratorSet decorators, typename BarrierSetT>
171 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
172 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);
173 }
174
175 template <DecoratorSet decorators, typename BarrierSetT>
176 template <typename T>
177 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_not_in_heap(T* addr, oop compare_value, oop new_value) {
178 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
179 bs->storeval_barrier(new_value);
180
181 oop res;
182 oop expected = compare_value;
183 do {
184 compare_value = expected;
185 res = Raw::oop_atomic_cmpxchg(addr, compare_value, new_value);
186 expected = res;
187 } while ((compare_value != expected) && (resolve_forwarded(compare_value) == resolve_forwarded(expected)));
188
189 // Note: We don't need a keep-alive-barrier here. We already enqueue any loaded reference for SATB anyway,
190 // because it must be the previous value.
191 if (res != NULL) {
192 res = ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(res);
193 bs->satb_enqueue(res);
194 }
195 return res;
196 }
197
198 template <DecoratorSet decorators, typename BarrierSetT>
199 template <typename T>
200 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap(T* addr, oop compare_value, oop new_value) {
201 return oop_atomic_cmpxchg_not_in_heap(addr, compare_value, new_value);
202 }
203
204 template <DecoratorSet decorators, typename BarrierSetT>
205 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap_at(oop base, ptrdiff_t offset, oop compare_value, oop new_value) {
206 return oop_atomic_cmpxchg_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), compare_value, new_value);
207 }
208
209 template <DecoratorSet decorators, typename BarrierSetT>
210 template <typename T>
211 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_not_in_heap(T* addr, oop new_value) {
212 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
213 bs->storeval_barrier(new_value);
214
215 oop previous = Raw::oop_atomic_xchg(addr, new_value);
216
217 // Note: We don't need a keep-alive-barrier here. We already enqueue any loaded reference for SATB anyway,
218 // because it must be the previous value.
219 if (previous != NULL) {
220 previous = ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(previous);
221 bs->satb_enqueue(previous);
222 }
223 return previous;
224 }
225
226 template <DecoratorSet decorators, typename BarrierSetT>
227 template <typename T>
228 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap(T* addr, oop new_value) {
229 return oop_atomic_xchg_not_in_heap(addr, new_value);
230 }
231
232 template <DecoratorSet decorators, typename BarrierSetT>
233 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap_at(oop base, ptrdiff_t offset, oop new_value) {
234 return oop_atomic_xchg_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), new_value);
235 }
236
237 // Clone barrier support
238 template <DecoratorSet decorators, typename BarrierSetT>
239 void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::clone_in_heap(oop src, oop dst, size_t size) {
240 if (ShenandoahCloneBarrier) {
241 ShenandoahBarrierSet::barrier_set()->clone_barrier_runtime(src);
242 }
243 Raw::clone(src, dst, size);
244 }
245
246 template <DecoratorSet decorators, typename BarrierSetT>
247 template <typename T>
248 bool ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
249 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
250 size_t length) {
251 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
252 bs->arraycopy_barrier(arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw),
253 arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw),
254 length);
255 return Raw::oop_arraycopy_in_heap(src_obj, src_offset_in_bytes, src_raw, dst_obj, dst_offset_in_bytes, dst_raw, length);
256 }
257
258 template <class T, bool HAS_FWD, bool EVAC, bool ENQUEUE>
259 void ShenandoahBarrierSet::arraycopy_work(T* src, size_t count) {
260 assert(HAS_FWD == _heap->has_forwarded_objects(), "Forwarded object status is sane");
261
262 Thread* thread = Thread::current();
263 SATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
264 ShenandoahMarkingContext* ctx = _heap->marking_context();
265 const ShenandoahCollectionSet* const cset = _heap->collection_set();
266 T* end = src + count;
267 for (T* elem_ptr = src; elem_ptr < end; elem_ptr++) {
268 T o = RawAccess<>::oop_load(elem_ptr);
269 if (!CompressedOops::is_null(o)) {
270 oop obj = CompressedOops::decode_not_null(o);
271 if (HAS_FWD && cset->is_in(obj)) {
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_barrier(T* src, T* dst, size_t count) {
289 if (count == 0) {
290 return;
291 }
292 int gc_state = _heap->gc_state();
293 if ((gc_state & ShenandoahHeap::MARKING) != 0) {
294 arraycopy_marking(dst, count);
295 } else if ((gc_state & ShenandoahHeap::EVACUATION) != 0) {
296 arraycopy_evacuation(src, count);
297 } else if ((gc_state & ShenandoahHeap::UPDATEREFS) != 0) {
298 arraycopy_update(src, count);
299 }
300 }
301
302 template <class T>
303 void ShenandoahBarrierSet::arraycopy_marking(T* array, size_t count) {
304 assert(_heap->is_concurrent_mark_in_progress(), "only during marking");
305 if (!_heap->marking_context()->allocated_after_mark_start(reinterpret_cast<HeapWord*>(array))) {
306 arraycopy_work<T, false, false, true>(array, count);
307 }
308 }
309
310 inline bool ShenandoahBarrierSet::need_bulk_update(HeapWord* ary) {
311 return ary < _heap->heap_region_containing(ary)->get_update_watermark();
312 }
313
314 template <class T>
315 void ShenandoahBarrierSet::arraycopy_evacuation(T* src, size_t count) {
316 assert(_heap->is_evacuation_in_progress(), "only during evacuation");
317 if (need_bulk_update(reinterpret_cast<HeapWord*>(src))) {
318 ShenandoahEvacOOMScope oom_evac;
319 arraycopy_work<T, true, true, false>(src, count);
320 }
321 }
322
323 template <class T>
324 void ShenandoahBarrierSet::arraycopy_update(T* src, size_t count) {
325 assert(_heap->is_update_refs_in_progress(), "only during update-refs");
326 if (need_bulk_update(reinterpret_cast<HeapWord*>(src))) {
327 arraycopy_work<T, true, false, false>(src, count);
328 }
329 }
330
331 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP