1 /*
2 * Copyright (c) 2000, 2018, Oracle and/or its affiliates. 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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_VM_GC_SHARED_BARRIERSET_HPP
26 #define SHARE_VM_GC_SHARED_BARRIERSET_HPP
27
28 #include "gc/shared/barrierSetConfig.hpp"
29 #include "memory/memRegion.hpp"
30 #include "oops/access.hpp"
31 #include "oops/accessBackend.hpp"
32 #include "oops/oopsHierarchy.hpp"
33 #include "utilities/fakeRttiSupport.hpp"
34 #include "utilities/macros.hpp"
35
36 class BarrierSetAssembler;
37 class BarrierSetC1;
38 class BarrierSetC2;
39 class JavaThread;
40
41 // This class provides the interface between a barrier implementation and
42 // the rest of the system.
43
44 class BarrierSet: public CHeapObj<mtGC> {
45 friend class VMStructs;
46
47 static BarrierSet* _barrier_set;
48
49 public:
50 enum Name {
51 #define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
52 FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
53 #undef BARRIER_SET_DECLARE_BS_ENUM
54 UnknownBS
55 };
56
57 protected:
58 // Fake RTTI support. For a derived class T to participate
59 // - T must have a corresponding Name entry.
60 // - GetName<T> must be specialized to return the corresponding Name
61 // entry.
62 // - If T is a base class, the constructor must have a FakeRtti
63 // parameter and pass it up to its base class, with the tag set
64 // augmented with the corresponding Name entry.
65 // - If T is a concrete class, the constructor must create a
66 // FakeRtti object whose tag set includes the corresponding Name
67 // entry, and pass it up to its base class.
68 typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
69
70 private:
71 FakeRtti _fake_rtti;
72 BarrierSetAssembler* _barrier_set_assembler;
73 BarrierSetC1* _barrier_set_c1;
74 BarrierSetC2* _barrier_set_c2;
75
76 public:
77 // Metafunction mapping a class derived from BarrierSet to the
78 // corresponding Name enum tag.
79 template<typename T> struct GetName;
80
81 // Metafunction mapping a Name enum type to the corresponding
82 // lass derived from BarrierSet.
83 template<BarrierSet::Name T> struct GetType;
84
85 // Note: This is not presently the Name corresponding to the
86 // concrete class of this object.
87 BarrierSet::Name kind() const { return _fake_rtti.concrete_tag(); }
88
89 // Test whether this object is of the type corresponding to bsn.
90 bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
91
92 // End of fake RTTI support.
93
94 protected:
95 BarrierSet(BarrierSetAssembler* barrier_set_assembler,
96 BarrierSetC1* barrier_set_c1,
97 BarrierSetC2* barrier_set_c2,
98 const FakeRtti& fake_rtti) :
99 _fake_rtti(fake_rtti),
100 _barrier_set_assembler(barrier_set_assembler),
101 _barrier_set_c1(barrier_set_c1),
102 _barrier_set_c2(barrier_set_c2) {}
103 ~BarrierSet() { }
104
105 template <class BarrierSetAssemblerT>
106 static BarrierSetAssembler* make_barrier_set_assembler() {
107 return NOT_ZERO(new BarrierSetAssemblerT()) ZERO_ONLY(NULL);
108 }
109
110 template <class BarrierSetC1T>
111 static BarrierSetC1* make_barrier_set_c1() {
112 return COMPILER1_PRESENT(new BarrierSetC1T()) NOT_COMPILER1(NULL);
113 }
114
115 template <class BarrierSetC2T>
116 static BarrierSetC2* make_barrier_set_c2() {
117 return COMPILER2_PRESENT(new BarrierSetC2T()) NOT_COMPILER2(NULL);
118 }
119
120 public:
121 // Support for optimizing compilers to call the barrier set on slow path allocations
122 // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks.
123 // The allocation is safe to use iff it returns true. If not, the slow-path allocation
124 // is redone until it succeeds. This can e.g. prevent allocations from the slow path
125 // to be in old.
126 virtual void on_slowpath_allocation_exit(JavaThread* thread, oop new_obj) {}
127 virtual void on_thread_create(Thread* thread) {}
128 virtual void on_thread_destroy(Thread* thread) {}
129 virtual void on_thread_attach(JavaThread* thread) {}
130 virtual void on_thread_detach(JavaThread* thread) {}
131 virtual void make_parsable(JavaThread* thread) {}
132
133 public:
134 // Print a description of the memory for the barrier set
135 virtual void print_on(outputStream* st) const = 0;
136
137 static BarrierSet* barrier_set() { return _barrier_set; }
138 static void set_barrier_set(BarrierSet* barrier_set);
139
140 BarrierSetAssembler* barrier_set_assembler() {
141 assert(_barrier_set_assembler != NULL, "should be set");
142 return _barrier_set_assembler;
143 }
144
145 BarrierSetC1* barrier_set_c1() {
146 assert(_barrier_set_c1 != NULL, "should be set");
147 return _barrier_set_c1;
148 }
149
150 BarrierSetC2* barrier_set_c2() {
151 assert(_barrier_set_c2 != NULL, "should be set");
152 return _barrier_set_c2;
153 }
154
155 #ifdef ASSERT
156 virtual void verify_safe_oop(oop p);
157 #endif
158
159 // The AccessBarrier of a BarrierSet subclass is called by the Access API
160 // (cf. oops/access.hpp) to perform decorated accesses. GC implementations
161 // may override these default access operations by declaring an
162 // AccessBarrier class in its BarrierSet. Its accessors will then be
163 // automatically resolved at runtime.
164 //
165 // In order to register a new FooBarrierSet::AccessBarrier with the Access API,
166 // the following steps should be taken:
167 // 1) Provide an enum "name" for the BarrierSet in barrierSetConfig.hpp
168 // 2) Make sure the barrier set headers are included from barrierSetConfig.inline.hpp
169 // 3) Provide specializations for BarrierSet::GetName and BarrierSet::GetType.
170 template <DecoratorSet decorators, typename BarrierSetT>
171 class AccessBarrier: protected RawAccessBarrier<decorators> {
172 private:
173 typedef RawAccessBarrier<decorators> Raw;
174
175 public:
176 // Primitive heap accesses. These accessors get resolved when
177 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
178 // not an oop_* overload, and the barrier strength is AS_NORMAL.
179 template <typename T>
180 static T load_in_heap(T* addr) {
181 return Raw::template load<T>(addr);
182 }
183
184 template <typename T>
185 static T load_in_heap_at(oop base, ptrdiff_t offset) {
186 return Raw::template load_at<T>(base, offset);
187 }
188
189 template <typename T>
190 static void store_in_heap(T* addr, T value) {
191 Raw::store(addr, value);
192 }
193
194 template <typename T>
195 static void store_in_heap_at(oop base, ptrdiff_t offset, T value) {
196 Raw::store_at(base, offset, value);
197 }
198
199 template <typename T>
200 static T atomic_cmpxchg_in_heap(T new_value, T* addr, T compare_value) {
201 return Raw::atomic_cmpxchg(new_value, addr, compare_value);
202 }
203
204 template <typename T>
205 static T atomic_cmpxchg_in_heap_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {
206 return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
207 }
208
209 template <typename T>
210 static T atomic_xchg_in_heap(T new_value, T* addr) {
211 return Raw::atomic_xchg(new_value, addr);
212 }
213
214 template <typename T>
215 static T atomic_xchg_in_heap_at(T new_value, oop base, ptrdiff_t offset) {
216 return Raw::atomic_xchg_at(new_value, base, offset);
217 }
218
219 template <typename T>
220 static void arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
221 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
222 size_t length) {
223 Raw::arraycopy(src_obj, src_offset_in_bytes, src_raw,
224 dst_obj, dst_offset_in_bytes, dst_raw,
225 length);
226 }
227
228 // Heap oop accesses. These accessors get resolved when
229 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
230 // an oop_* overload, and the barrier strength is AS_NORMAL.
231 template <typename T>
232 static oop oop_load_in_heap(T* addr) {
233 return Raw::template oop_load<oop>(addr);
234 }
235
236 static oop oop_load_in_heap_at(oop base, ptrdiff_t offset) {
237 return Raw::template oop_load_at<oop>(base, offset);
238 }
239
240 template <typename T>
241 static void oop_store_in_heap(T* addr, oop value) {
242 Raw::oop_store(addr, value);
243 }
244
245 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
246 Raw::oop_store_at(base, offset, value);
247 }
248
249 template <typename T>
250 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
251 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
252 }
253
254 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
255 return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
256 }
257
258 template <typename T>
259 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr) {
260 return Raw::oop_atomic_xchg(new_value, addr);
261 }
262
263 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
264 return Raw::oop_atomic_xchg_at(new_value, base, offset);
265 }
266
267 template <typename T>
268 static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
269 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
270 size_t length) {
271 return Raw::oop_arraycopy(src_obj, src_offset_in_bytes, src_raw,
272 dst_obj, dst_offset_in_bytes, dst_raw,
273 length);
274 }
275
276 // Off-heap oop accesses. These accessors get resolved when
277 // IN_HEAP is not set (e.g. when using the NativeAccess API), it is
278 // an oop* overload, and the barrier strength is AS_NORMAL.
279 template <typename T>
280 static oop oop_load_not_in_heap(T* addr) {
281 return Raw::template oop_load<oop>(addr);
282 }
283
284 template <typename T>
285 static void oop_store_not_in_heap(T* addr, oop value) {
286 Raw::oop_store(addr, value);
287 }
288
289 template <typename T>
290 static oop oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
291 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
292 }
293
294 template <typename T>
295 static oop oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
296 return Raw::oop_atomic_xchg(new_value, addr);
297 }
298
299 // Clone barrier support
300 static void clone_in_heap(oop src, oop dst, size_t size) {
301 Raw::clone(src, dst, size);
302 }
303
304 static oop resolve(oop obj) {
305 return Raw::resolve(obj);
306 }
307
308 static bool equals(oop o1, oop o2) {
309 return Raw::equals(o1, o2);
310 }
311 };
312 };
313
314 template<typename T>
315 inline T* barrier_set_cast(BarrierSet* bs) {
316 assert(bs->is_a(BarrierSet::GetName<T>::value), "wrong type of barrier set");
317 return static_cast<T*>(bs);
318 }
319
320 #endif // SHARE_VM_GC_SHARED_BARRIERSET_HPP