1 /*
2 * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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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,
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23 */
24
25 #ifndef SHARE_GC_SHARED_BARRIERSET_HPP
26 #define SHARE_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 BarrierSetNMethod;
40 class JavaThread;
41
42 // This class provides the interface between a barrier implementation and
43 // the rest of the system.
44
45 class BarrierSet: public CHeapObj<mtGC> {
46 friend class VMStructs;
47
48 static BarrierSet* _barrier_set;
49
50 public:
51 enum Name {
52 #define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
53 FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
54 #undef BARRIER_SET_DECLARE_BS_ENUM
55 UnknownBS
56 };
57
58 protected:
59 // Fake RTTI support. For a derived class T to participate
60 // - T must have a corresponding Name entry.
61 // - GetName<T> must be specialized to return the corresponding Name
62 // entry.
63 // - If T is a base class, the constructor must have a FakeRtti
64 // parameter and pass it up to its base class, with the tag set
65 // augmented with the corresponding Name entry.
66 // - If T is a concrete class, the constructor must create a
67 // FakeRtti object whose tag set includes the corresponding Name
68 // entry, and pass it up to its base class.
69 typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
70
71 private:
72 FakeRtti _fake_rtti;
73 BarrierSetAssembler* _barrier_set_assembler;
74 BarrierSetC1* _barrier_set_c1;
75 BarrierSetC2* _barrier_set_c2;
76 BarrierSetNMethod* _barrier_set_nmethod;
77
78 public:
79 // Metafunction mapping a class derived from BarrierSet to the
80 // corresponding Name enum tag.
81 template<typename T> struct GetName;
82
83 // Metafunction mapping a Name enum type to the corresponding
84 // lass derived from BarrierSet.
85 template<BarrierSet::Name T> struct GetType;
86
87 // Note: This is not presently the Name corresponding to the
88 // concrete class of this object.
89 BarrierSet::Name kind() const { return _fake_rtti.concrete_tag(); }
90
91 // Test whether this object is of the type corresponding to bsn.
92 bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
93
94 // End of fake RTTI support.
95
96 protected:
97 BarrierSet(BarrierSetAssembler* barrier_set_assembler,
98 BarrierSetC1* barrier_set_c1,
99 BarrierSetC2* barrier_set_c2,
100 BarrierSetNMethod* barrier_set_nmethod,
101 const FakeRtti& fake_rtti) :
102 _fake_rtti(fake_rtti),
103 _barrier_set_assembler(barrier_set_assembler),
104 _barrier_set_c1(barrier_set_c1),
105 _barrier_set_c2(barrier_set_c2),
106 _barrier_set_nmethod(barrier_set_nmethod) {}
107 ~BarrierSet() { }
108
109 template <class BarrierSetAssemblerT>
110 static BarrierSetAssembler* make_barrier_set_assembler() {
111 return NOT_ZERO(new BarrierSetAssemblerT()) ZERO_ONLY(NULL);
112 }
113
114 template <class BarrierSetC1T>
115 static BarrierSetC1* make_barrier_set_c1() {
116 return COMPILER1_PRESENT(new BarrierSetC1T()) NOT_COMPILER1(NULL);
117 }
118
119 template <class BarrierSetC2T>
120 static BarrierSetC2* make_barrier_set_c2() {
121 return COMPILER2_PRESENT(new BarrierSetC2T()) NOT_COMPILER2(NULL);
122 }
123
124 public:
125 // Support for optimizing compilers to call the barrier set on slow path allocations
126 // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks.
127 // The allocation is safe to use iff it returns true. If not, the slow-path allocation
128 // is redone until it succeeds. This can e.g. prevent allocations from the slow path
129 // to be in old.
130 virtual void on_slowpath_allocation_exit(JavaThread* thread, oop new_obj) {}
131 virtual void on_thread_create(Thread* thread) {}
132 virtual void on_thread_destroy(Thread* thread) {}
133 virtual void on_thread_attach(Thread* thread) {}
134 virtual void on_thread_detach(Thread* thread) {}
135 virtual bool needs_sts_sync_on_attach_detach() { return false; }
136 virtual void make_parsable(JavaThread* thread) {}
137
138 #ifdef CHECK_UNHANDLED_OOPS
139 virtual bool oop_equals_operator_allowed() { return true; }
140 #endif
141
142 public:
143 // Print a description of the memory for the barrier set
144 virtual void print_on(outputStream* st) const = 0;
145
146 static BarrierSet* barrier_set() { return _barrier_set; }
147 static void set_barrier_set(BarrierSet* barrier_set);
148
149 BarrierSetAssembler* barrier_set_assembler() {
150 assert(_barrier_set_assembler != NULL, "should be set");
151 return _barrier_set_assembler;
152 }
153
154 BarrierSetC1* barrier_set_c1() {
155 assert(_barrier_set_c1 != NULL, "should be set");
156 return _barrier_set_c1;
157 }
158
159 BarrierSetC2* barrier_set_c2() {
160 assert(_barrier_set_c2 != NULL, "should be set");
161 return _barrier_set_c2;
162 }
163
164 BarrierSetNMethod* barrier_set_nmethod() {
165 return _barrier_set_nmethod;
166 }
167
168 // The AccessBarrier of a BarrierSet subclass is called by the Access API
169 // (cf. oops/access.hpp) to perform decorated accesses. GC implementations
170 // may override these default access operations by declaring an
171 // AccessBarrier class in its BarrierSet. Its accessors will then be
172 // automatically resolved at runtime.
173 //
174 // In order to register a new FooBarrierSet::AccessBarrier with the Access API,
175 // the following steps should be taken:
176 // 1) Provide an enum "name" for the BarrierSet in barrierSetConfig.hpp
177 // 2) Make sure the barrier set headers are included from barrierSetConfig.inline.hpp
178 // 3) Provide specializations for BarrierSet::GetName and BarrierSet::GetType.
179 template <DecoratorSet decorators, typename BarrierSetT>
180 class AccessBarrier: protected RawAccessBarrier<decorators> {
181 private:
182 typedef RawAccessBarrier<decorators> Raw;
183
184 public:
185 // Primitive heap accesses. These accessors get resolved when
186 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
187 // not an oop_* overload, and the barrier strength is AS_NORMAL.
188 template <typename T>
189 static T load_in_heap(T* addr) {
190 return Raw::template load<T>(addr);
191 }
192
193 template <typename T>
194 static T load_in_heap_at(oop base, ptrdiff_t offset) {
195 return Raw::template load_at<T>(base, offset);
196 }
197
198 template <typename T>
199 static void store_in_heap(T* addr, T value) {
200 Raw::store(addr, value);
201 }
202
203 template <typename T>
204 static void store_in_heap_at(oop base, ptrdiff_t offset, T value) {
205 Raw::store_at(base, offset, value);
206 }
207
208 template <typename T>
209 static T atomic_cmpxchg_in_heap(T new_value, T* addr, T compare_value) {
210 return Raw::atomic_cmpxchg(new_value, addr, compare_value);
211 }
212
213 template <typename T>
214 static T atomic_cmpxchg_in_heap_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {
215 return Raw::atomic_cmpxchg_at(new_value, base, offset, compare_value);
216 }
217
218 template <typename T>
219 static T atomic_xchg_in_heap(T new_value, T* addr) {
220 return Raw::atomic_xchg(new_value, addr);
221 }
222
223 template <typename T>
224 static T atomic_xchg_in_heap_at(T new_value, oop base, ptrdiff_t offset) {
225 return Raw::atomic_xchg_at(new_value, base, offset);
226 }
227
228 template <typename T>
229 static void arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
230 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
231 size_t length) {
232 Raw::arraycopy(src_obj, src_offset_in_bytes, src_raw,
233 dst_obj, dst_offset_in_bytes, dst_raw,
234 length);
235 }
236
237 // Heap oop accesses. These accessors get resolved when
238 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
239 // an oop_* overload, and the barrier strength is AS_NORMAL.
240 template <typename T>
241 static oop oop_load_in_heap(T* addr) {
242 return Raw::template oop_load<oop>(addr);
243 }
244
245 static oop oop_load_in_heap_at(oop base, ptrdiff_t offset) {
246 return Raw::template oop_load_at<oop>(base, offset);
247 }
248
249 template <typename T>
250 static void oop_store_in_heap(T* addr, oop value) {
251 Raw::oop_store(addr, value);
252 }
253
254 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
255 Raw::oop_store_at(base, offset, value);
256 }
257
258 template <typename T>
259 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
260 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
261 }
262
263 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
264 return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
265 }
266
267 template <typename T>
268 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr) {
269 return Raw::oop_atomic_xchg(new_value, addr);
270 }
271
272 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
273 return Raw::oop_atomic_xchg_at(new_value, base, offset);
274 }
275
276 template <typename T>
277 static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
278 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
279 size_t length);
280
281 // Off-heap oop accesses. These accessors get resolved when
282 // IN_HEAP is not set (e.g. when using the NativeAccess API), it is
283 // an oop* overload, and the barrier strength is AS_NORMAL.
284 template <typename T>
285 static oop oop_load_not_in_heap(T* addr) {
286 return Raw::template oop_load<oop>(addr);
287 }
288
289 template <typename T>
290 static void oop_store_not_in_heap(T* addr, oop value) {
291 Raw::oop_store(addr, value);
292 }
293
294 template <typename T>
295 static oop oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
296 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
297 }
298
299 template <typename T>
300 static oop oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
301 return Raw::oop_atomic_xchg(new_value, addr);
302 }
303
304 // Clone barrier support
305 static void clone_in_heap(oop src, oop dst, size_t size) {
306 Raw::clone(src, dst, size);
307 }
308
309 static oop resolve(oop obj) {
310 return Raw::resolve(obj);
311 }
312
313 static bool equals(oop o1, oop o2) {
314 return Raw::equals(o1, o2);
315 }
316 };
317 };
318
319 template<typename T>
320 inline T* barrier_set_cast(BarrierSet* bs) {
321 assert(bs->is_a(BarrierSet::GetName<T>::value), "wrong type of barrier set");
322 return static_cast<T*>(bs);
323 }
324
325 #endif // SHARE_GC_SHARED_BARRIERSET_HPP