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