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_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
25 #define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP
26
27 #include "gc/shared/barrierSet.hpp"
28 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
29 #include "gc/shenandoah/shenandoahBrooksPointer.inline.hpp"
30 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
32 #include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
33 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
34
35 inline oop ShenandoahBarrierSet::resolve_forwarded_not_null(oop p) {
36 return ShenandoahBrooksPointer::forwardee(p);
37 }
38
39 inline oop ShenandoahBarrierSet::resolve_forwarded(oop p) {
40 if (((HeapWord*) p) != NULL) {
41 return resolve_forwarded_not_null(p);
42 } else {
43 return p;
44 }
45 }
46
47 template <DecoratorSet decorators, typename BarrierSetT>
48 template <typename T>
49 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap(T* addr) {
50 oop value = Raw::oop_load_in_heap(addr);
51 value = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(value);
52 keep_alive_if_weak(decorators, value);
53 return value;
54 }
55
56 template <DecoratorSet decorators, typename BarrierSetT>
57 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_in_heap_at(oop base, ptrdiff_t offset) {
58 oop value = Raw::oop_load_in_heap_at(base, offset);
59 value = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(value);
60 keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);
61 return value;
62 }
63
64 template <DecoratorSet decorators, typename BarrierSetT>
65 template <typename T>
66 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_load_not_in_heap(T* addr) {
67 oop value = Raw::oop_load_not_in_heap(addr);
68 value = ShenandoahBarrierSet::barrier_set()->load_reference_barrier(value);
69 keep_alive_if_weak(decorators, value);
70 return value;
71 }
72
73 template <DecoratorSet decorators, typename BarrierSetT>
74 template <typename T>
75 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap(T* addr, oop value) {
76 ShenandoahBarrierSet::barrier_set()->storeval_barrier(value);
77 const bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
78 if (keep_alive) {
79 ShenandoahBarrierSet::barrier_set()->write_ref_field_pre_work(addr, value);
80 }
81 Raw::oop_store_in_heap(addr, value);
82 }
83
84 template <DecoratorSet decorators, typename BarrierSetT>
85 inline void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
86 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value);
87 }
88
89 template <DecoratorSet decorators, typename BarrierSetT>
90 template <typename T>
91 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
92 oop res;
93 oop expected = compare_value;
94 do {
95 compare_value = expected;
96 res = Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
97 expected = res;
98 } while ((! oopDesc::equals_raw(compare_value, expected)) && oopDesc::equals_raw(resolve_forwarded(compare_value), resolve_forwarded(expected)));
99 if (res != NULL) {
100 return ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(res);
101 } else {
102 return res;
103 }
104 }
105
106 template <DecoratorSet decorators, typename BarrierSetT>
107 template <typename T>
108 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap_impl(oop new_value, T* addr, oop compare_value) {
109 ShenandoahBarrierSet::barrier_set()->storeval_barrier(new_value);
110 oop result = oop_atomic_cmpxchg_not_in_heap(new_value, addr, compare_value);
111 const bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
112 if (keep_alive && ShenandoahSATBBarrier && !CompressedOops::is_null(result) &&
113 oopDesc::equals_raw(result, compare_value) &&
114 ShenandoahHeap::heap()->is_concurrent_mark_in_progress()) {
115 ShenandoahBarrierSet::barrier_set()->enqueue(result);
116 }
117 return result;
118 }
119
120 template <DecoratorSet decorators, typename BarrierSetT>
121 template <typename T>
122 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
123 oop result = oop_atomic_cmpxchg_in_heap_impl(new_value, addr, compare_value);
124 keep_alive_if_weak(decorators, result);
125 return result;
126 }
127
128 template <DecoratorSet decorators, typename BarrierSetT>
129 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
130 oop result = oop_atomic_cmpxchg_in_heap_impl(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value);
131 keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), result);
132 return result;
133 }
134
135 template <DecoratorSet decorators, typename BarrierSetT>
136 template <typename T>
137 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
138 oop previous = Raw::oop_atomic_xchg(new_value, addr);
139 if (previous != NULL) {
140 return ShenandoahBarrierSet::barrier_set()->load_reference_barrier_not_null(previous);
141 } else {
142 return previous;
143 }
144 }
145
146 template <DecoratorSet decorators, typename BarrierSetT>
147 template <typename T>
148 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap_impl(oop new_value, T* addr) {
149 ShenandoahBarrierSet::barrier_set()->storeval_barrier(new_value);
150 oop result = oop_atomic_xchg_not_in_heap(new_value, addr);
151 const bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0;
152 if (keep_alive && ShenandoahSATBBarrier && !CompressedOops::is_null(result) &&
153 ShenandoahHeap::heap()->is_concurrent_mark_in_progress()) {
154 ShenandoahBarrierSet::barrier_set()->enqueue(result);
155 }
156 return result;
157 }
158
159 template <DecoratorSet decorators, typename BarrierSetT>
160 template <typename T>
161 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap(oop new_value, T* addr) {
162 oop result = oop_atomic_xchg_in_heap_impl(new_value, addr);
163 keep_alive_if_weak(addr, result);
164 return result;
165 }
166
167 template <DecoratorSet decorators, typename BarrierSetT>
168 inline oop ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
169 oop result = oop_atomic_xchg_in_heap_impl(new_value, AccessInternal::oop_field_addr<decorators>(base, offset));
170 keep_alive_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), result);
171 return result;
172 }
173
174 template <typename T>
175 bool ShenandoahBarrierSet::arraycopy_loop_1(T* src, T* dst, size_t length, Klass* bound,
176 bool checkcast, bool satb, bool disjoint,
177 ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode) {
178 if (checkcast) {
179 return arraycopy_loop_2<T, true>(src, dst, length, bound, satb, disjoint, storeval_mode);
180 } else {
181 return arraycopy_loop_2<T, false>(src, dst, length, bound, satb, disjoint, storeval_mode);
182 }
183 }
184
185 template <typename T, bool CHECKCAST>
186 bool ShenandoahBarrierSet::arraycopy_loop_2(T* src, T* dst, size_t length, Klass* bound,
187 bool satb, bool disjoint,
188 ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode) {
189 if (satb) {
190 return arraycopy_loop_3<T, CHECKCAST, true>(src, dst, length, bound, disjoint, storeval_mode);
191 } else {
192 return arraycopy_loop_3<T, CHECKCAST, false>(src, dst, length, bound, disjoint, storeval_mode);
193 }
194 }
195
196 template <typename T, bool CHECKCAST, bool SATB>
197 bool ShenandoahBarrierSet::arraycopy_loop_3(T* src, T* dst, size_t length, Klass* bound, bool disjoint,
198 ShenandoahBarrierSet::ArrayCopyStoreValMode storeval_mode) {
199 switch (storeval_mode) {
200 case NONE:
201 return arraycopy_loop<T, CHECKCAST, SATB, NONE>(src, dst, length, bound, disjoint);
202 case READ_BARRIER:
203 return arraycopy_loop<T, CHECKCAST, SATB, READ_BARRIER>(src, dst, length, bound, disjoint);
204 case WRITE_BARRIER:
205 return arraycopy_loop<T, CHECKCAST, SATB, WRITE_BARRIER>(src, dst, length, bound, disjoint);
206 default:
207 ShouldNotReachHere();
208 return true; // happy compiler
209 }
210 }
211
212 template <typename T, bool CHECKCAST, bool SATB, ShenandoahBarrierSet::ArrayCopyStoreValMode STOREVAL_MODE>
213 bool ShenandoahBarrierSet::arraycopy_loop(T* src, T* dst, size_t length, Klass* bound, bool disjoint) {
214 Thread* thread = Thread::current();
215 ShenandoahMarkingContext* ctx = _heap->marking_context();
216 ShenandoahEvacOOMScope oom_evac_scope;
217
218 // We need to handle four cases:
219 //
220 // a) src < dst, conjoint, can only copy backward only
221 // [...src...]
222 // [...dst...]
223 //
224 // b) src < dst, disjoint, can only copy forward, because types may mismatch
225 // [...src...]
226 // [...dst...]
227 //
228 // c) src > dst, conjoint, can copy forward only
229 // [...src...]
230 // [...dst...]
231 //
232 // d) src > dst, disjoint, can only copy forward, because types may mismatch
233 // [...src...]
234 // [...dst...]
235 //
236 if (src > dst || disjoint) {
237 // copy forward:
238 T* cur_src = src;
239 T* cur_dst = dst;
240 T* src_end = src + length;
241 for (; cur_src < src_end; cur_src++, cur_dst++) {
242 if (!arraycopy_element<T, CHECKCAST, SATB, STOREVAL_MODE>(cur_src, cur_dst, bound, thread, ctx)) {
243 return false;
244 }
245 }
246 } else {
247 // copy backward:
248 T* cur_src = src + length - 1;
249 T* cur_dst = dst + length - 1;
250 for (; cur_src >= src; cur_src--, cur_dst--) {
251 if (!arraycopy_element<T, CHECKCAST, SATB, STOREVAL_MODE>(cur_src, cur_dst, bound, thread, ctx)) {
252 return false;
253 }
254 }
255 }
256 return true;
257 }
258
259 template <typename T, bool CHECKCAST, bool SATB, ShenandoahBarrierSet::ArrayCopyStoreValMode STOREVAL_MODE>
260 bool ShenandoahBarrierSet::arraycopy_element(T* cur_src, T* cur_dst, Klass* bound, Thread* const thread, ShenandoahMarkingContext* const ctx) {
261 T o = RawAccess<>::oop_load(cur_src);
262
263 if (SATB) {
264 assert(ShenandoahThreadLocalData::satb_mark_queue(thread).is_active(), "Shouldn't be here otherwise");
265 T prev = RawAccess<>::oop_load(cur_dst);
266 if (!CompressedOops::is_null(prev)) {
267 oop prev_obj = CompressedOops::decode_not_null(prev);
268 switch (STOREVAL_MODE) {
269 case NONE:
270 break;
271 case READ_BARRIER:
272 case WRITE_BARRIER:
273 // The write-barrier case cannot really happen. It's traversal-only and traversal
274 // doesn't currently use SATB. And even if it did, it would not be fatal to just do the normal RB here.
275 prev_obj = ShenandoahBarrierSet::resolve_forwarded_not_null(prev_obj);
276 }
277 if (!ctx->is_marked(prev_obj)) {
278 ShenandoahThreadLocalData::satb_mark_queue(thread).enqueue_known_active(prev_obj);
279 }
280 }
281 }
282
283 if (!CompressedOops::is_null(o)) {
284 oop obj = CompressedOops::decode_not_null(o);
285
286 if (CHECKCAST) {
287 assert(bound != NULL, "need element klass for checkcast");
288 if (!oopDesc::is_instanceof_or_null(obj, bound)) {
289 return false;
290 }
291 }
292
293 switch (STOREVAL_MODE) {
294 case NONE:
295 break;
296 case READ_BARRIER:
297 obj = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
298 break;
299 case WRITE_BARRIER:
300 if (_heap->in_collection_set(obj)) {
301 oop forw = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
302 if (oopDesc::equals_raw(forw, obj)) {
303 forw = _heap->evacuate_object(forw, thread);
304 }
305 obj = forw;
306 }
307 enqueue(obj);
308 break;
309 default:
310 ShouldNotReachHere();
311 }
312
313 RawAccess<IS_NOT_NULL>::oop_store(cur_dst, obj);
314 } else {
315 // Store null.
316 RawAccess<>::oop_store(cur_dst, o);
317 }
318 return true;
319 }
320
321 // Clone barrier support
322 template <DecoratorSet decorators, typename BarrierSetT>
323 void ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::clone_in_heap(oop src, oop dst, size_t size) {
324 Raw::clone(src, dst, size);
325 ShenandoahBarrierSet::barrier_set()->write_region(MemRegion((HeapWord*) dst, size));
326 }
327
328 template <DecoratorSet decorators, typename BarrierSetT>
329 template <typename T>
330 bool ShenandoahBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
331 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
332 size_t length) {
333 ShenandoahHeap* heap = ShenandoahHeap::heap();
334 bool satb = ShenandoahSATBBarrier && heap->is_concurrent_mark_in_progress();
335 bool checkcast = HasDecorator<decorators, ARRAYCOPY_CHECKCAST>::value;
336 bool disjoint = HasDecorator<decorators, ARRAYCOPY_DISJOINT>::value;
337 ArrayCopyStoreValMode storeval_mode;
338 if (heap->has_forwarded_objects()) {
339 if (heap->is_concurrent_traversal_in_progress()) {
340 storeval_mode = WRITE_BARRIER;
341 } else if (heap->is_update_refs_in_progress()) {
342 storeval_mode = READ_BARRIER;
343 } else {
344 assert(heap->is_idle() || heap->is_evacuation_in_progress(), "must not have anything in progress");
345 storeval_mode = NONE; // E.g. during evac or outside cycle
346 }
347 } else {
348 assert(heap->is_stable() || heap->is_concurrent_mark_in_progress(), "must not have anything in progress");
349 storeval_mode = NONE;
350 }
351
352 if (!satb && !checkcast && storeval_mode == NONE) {
353 // Short-circuit to bulk copy.
354 return Raw::oop_arraycopy(src_obj, src_offset_in_bytes, src_raw, dst_obj, dst_offset_in_bytes, dst_raw, length);
355 }
356
357 src_raw = arrayOopDesc::obj_offset_to_raw(src_obj, src_offset_in_bytes, src_raw);
358 dst_raw = arrayOopDesc::obj_offset_to_raw(dst_obj, dst_offset_in_bytes, dst_raw);
359
360 Klass* bound = objArrayOop(dst_obj)->element_klass();
361 ShenandoahBarrierSet* bs = ShenandoahBarrierSet::barrier_set();
362 return bs->arraycopy_loop_1(src_raw, dst_raw, length, bound, checkcast, satb, disjoint, storeval_mode);
363 }
364
365 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSET_INLINE_HPP