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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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 #include "utilities/sizes.hpp"
36
37 class BarrierSetAssembler;
38 class BarrierSetC1;
39 class BarrierSetC2;
40 class JavaThread;
41 class nmethod;
42 class nmethodBarrier;
43
44 // This class provides the interface between a barrier implementation and
45 // the rest of the system.
46
47 class BarrierSet: public CHeapObj<mtGC> {
48 friend class VMStructs;
49
50 static BarrierSet* _barrier_set;
51
52 public:
53 enum Name {
54 #define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
55 FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
56 #undef BARRIER_SET_DECLARE_BS_ENUM
57 UnknownBS
58 };
59
60 protected:
61 // Fake RTTI support. For a derived class T to participate
62 // - T must have a corresponding Name entry.
63 // - GetName<T> must be specialized to return the corresponding Name
64 // entry.
65 // - If T is a base class, the constructor must have a FakeRtti
66 // parameter and pass it up to its base class, with the tag set
67 // augmented with the corresponding Name entry.
68 // - If T is a concrete class, the constructor must create a
69 // FakeRtti object whose tag set includes the corresponding Name
70 // entry, and pass it up to its base class.
71 typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
72
73 private:
74 FakeRtti _fake_rtti;
75 BarrierSetAssembler* _barrier_set_assembler;
76 BarrierSetC1* _barrier_set_c1;
77 BarrierSetC2* _barrier_set_c2;
78
79 public:
80 // Metafunction mapping a class derived from BarrierSet to the
81 // corresponding Name enum tag.
82 template<typename T> struct GetName;
83
84 // Metafunction mapping a Name enum type to the corresponding
85 // lass derived from BarrierSet.
86 template<BarrierSet::Name T> struct GetType;
87
88 // Note: This is not presently the Name corresponding to the
89 // concrete class of this object.
90 BarrierSet::Name kind() const { return _fake_rtti.concrete_tag(); }
91
92 // Test whether this object is of the type corresponding to bsn.
93 bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
94
95 // End of fake RTTI support.
96
97 protected:
98 BarrierSet(BarrierSetAssembler* barrier_set_assembler,
99 BarrierSetC1* barrier_set_c1,
100 BarrierSetC2* barrier_set_c2,
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 ~BarrierSet() { }
107
108 template <class BarrierSetAssemblerT>
109 static BarrierSetAssembler* make_barrier_set_assembler() {
110 return NOT_ZERO(new BarrierSetAssemblerT()) ZERO_ONLY(NULL);
111 }
112
113 template <class BarrierSetC1T>
114 static BarrierSetC1* make_barrier_set_c1() {
115 return COMPILER1_PRESENT(new BarrierSetC1T()) NOT_COMPILER1(NULL);
116 }
117
118 template <class BarrierSetC2T>
119 static BarrierSetC2* make_barrier_set_c2() {
120 return COMPILER2_PRESENT(new BarrierSetC2T()) NOT_COMPILER2(NULL);
121 }
122
123 public:
124 // Support for optimizing compilers to call the barrier set on slow path allocations
125 // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks.
126 // The allocation is safe to use iff it returns true. If not, the slow-path allocation
127 // is redone until it succeeds. This can e.g. prevent allocations from the slow path
128 // to be in old.
129 virtual void on_slowpath_allocation_exit(JavaThread* thread, oop new_obj) {}
130 virtual void on_thread_create(Thread* thread) {}
131 virtual void on_thread_destroy(Thread* thread) {}
132 virtual void on_thread_attach(JavaThread* thread) {}
133 virtual void on_thread_detach(JavaThread* thread) {}
134 virtual void make_parsable(JavaThread* thread) {}
135
136 // nmethod entry barrier support
137 virtual bool needs_nmethod_entry_barrier() const { return false; }
138 virtual ByteSize nmethod_entry_barrier_state_thread_offset() const { return in_ByteSize(0); }
139 virtual bool on_nmethod_entry_barrier(nmethod* nm, nmethodBarrier* nmbarrier);
140
141 public:
142 // Print a description of the memory for the barrier set
143 virtual void print_on(outputStream* st) const = 0;
144
145 static BarrierSet* barrier_set() { return _barrier_set; }
146 static void set_barrier_set(BarrierSet* barrier_set);
147
148 BarrierSetAssembler* barrier_set_assembler() {
149 assert(_barrier_set_assembler != NULL, "should be set");
150 return _barrier_set_assembler;
151 }
152
153 BarrierSetC1* barrier_set_c1() {
154 assert(_barrier_set_c1 != NULL, "should be set");
155 return _barrier_set_c1;
156 }
157
158 BarrierSetC2* barrier_set_c2() {
159 assert(_barrier_set_c2 != NULL, "should be set");
160 return _barrier_set_c2;
161 }
162
163 // The AccessBarrier of a BarrierSet subclass is called by the Access API
164 // (cf. oops/access.hpp) to perform decorated accesses. GC implementations
165 // may override these default access operations by declaring an
166 // AccessBarrier class in its BarrierSet. Its accessors will then be
167 // automatically resolved at runtime.
168 //
169 // In order to register a new FooBarrierSet::AccessBarrier with the Access API,
170 // the following steps should be taken:
171 // 1) Provide an enum "name" for the BarrierSet in barrierSetConfig.hpp
172 // 2) Make sure the barrier set headers are included from barrierSetConfig.inline.hpp
173 // 3) Provide specializations for BarrierSet::GetName and BarrierSet::GetType.
174 template <DecoratorSet decorators, typename BarrierSetT>
175 class AccessBarrier: protected RawAccessBarrier<decorators> {
176 private:
177 typedef RawAccessBarrier<decorators> Raw;
178
179 public:
180 // Primitive heap accesses. These accessors get resolved when
181 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
182 // not an oop_* overload, and the barrier strength is AS_NORMAL.
183 template <typename T>
184 static T load_in_heap(T* addr) {
185 return Raw::template load<T>(addr);
186 }
187
188 template <typename T>
189 static T load_in_heap_at(oop base, ptrdiff_t offset) {
190 return Raw::template load_at<T>(base, offset);
191 }
192
193 template <typename T>
194 static void store_in_heap(T* addr, T value) {
195 Raw::store(addr, value);
196 }
197
198 template <typename T>
199 static void store_in_heap_at(oop base, ptrdiff_t offset, T value) {
200 Raw::store_at(base, offset, value);
201 }
202
203 template <typename T>
204 static T atomic_cmpxchg_in_heap(T new_value, T* addr, T compare_value) {
205 return Raw::atomic_cmpxchg(new_value, addr, compare_value);
206 }
207
208 template <typename T>
209 static T atomic_cmpxchg_in_heap_at(T new_value, oop base, ptrdiff_t offset, T compare_value) {
210 return Raw::atomic_cmpxchg_at(new_value, base, offset, compare_value);
211 }
212
213 template <typename T>
214 static T atomic_xchg_in_heap(T new_value, T* addr) {
215 return Raw::atomic_xchg(new_value, addr);
216 }
217
218 template <typename T>
219 static T atomic_xchg_in_heap_at(T new_value, oop base, ptrdiff_t offset) {
220 return Raw::atomic_xchg_at(new_value, base, offset);
221 }
222
223 template <typename T>
224 static void arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
225 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
226 size_t length) {
227 Raw::arraycopy(src_obj, src_offset_in_bytes, src_raw,
228 dst_obj, dst_offset_in_bytes, dst_raw,
229 length);
230 }
231
232 // Heap oop accesses. These accessors get resolved when
233 // IN_HEAP is set (e.g. when using the HeapAccess API), it is
234 // an oop_* overload, and the barrier strength is AS_NORMAL.
235 template <typename T>
236 static oop oop_load_in_heap(T* addr) {
237 return Raw::template oop_load<oop>(addr);
238 }
239
240 static oop oop_load_in_heap_at(oop base, ptrdiff_t offset) {
241 return Raw::template oop_load_at<oop>(base, offset);
242 }
243
244 template <typename T>
245 static void oop_store_in_heap(T* addr, oop value) {
246 Raw::oop_store(addr, value);
247 }
248
249 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) {
250 Raw::oop_store_at(base, offset, value);
251 }
252
253 template <typename T>
254 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value) {
255 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
256 }
257
258 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) {
259 return Raw::oop_atomic_cmpxchg_at(new_value, base, offset, compare_value);
260 }
261
262 template <typename T>
263 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr) {
264 return Raw::oop_atomic_xchg(new_value, addr);
265 }
266
267 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) {
268 return Raw::oop_atomic_xchg_at(new_value, base, offset);
269 }
270
271 template <typename T>
272 static bool oop_arraycopy_in_heap(arrayOop src_obj, size_t src_offset_in_bytes, T* src_raw,
273 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
274 size_t length) {
275 return Raw::oop_arraycopy(src_obj, src_offset_in_bytes, src_raw,
276 dst_obj, dst_offset_in_bytes, dst_raw,
277 length);
278 }
279
280 // Off-heap oop accesses. These accessors get resolved when
281 // IN_HEAP is not set (e.g. when using the NativeAccess API), it is
282 // an oop* overload, and the barrier strength is AS_NORMAL.
283 template <typename T>
284 static oop oop_load_not_in_heap(T* addr) {
285 return Raw::template oop_load<oop>(addr);
286 }
287
288 template <typename T>
289 static void oop_store_not_in_heap(T* addr, oop value) {
290 Raw::oop_store(addr, value);
291 }
292
293 template <typename T>
294 static oop oop_atomic_cmpxchg_not_in_heap(oop new_value, T* addr, oop compare_value) {
295 return Raw::oop_atomic_cmpxchg(new_value, addr, compare_value);
296 }
297
298 template <typename T>
299 static oop oop_atomic_xchg_not_in_heap(oop new_value, T* addr) {
300 return Raw::oop_atomic_xchg(new_value, addr);
301 }
302
303 // Clone barrier support
304 static void clone_in_heap(oop src, oop dst, size_t size) {
305 Raw::clone(src, dst, size);
306 }
307
308 static oop resolve(oop obj) {
309 return Raw::resolve(obj);
310 }
311
312 static bool equals(oop o1, oop o2) {
313 return Raw::equals(o1, o2);
314 }
315 };
316 };
317
318 template<typename T>
319 inline T* barrier_set_cast(BarrierSet* bs) {
320 assert(bs->is_a(BarrierSet::GetName<T>::value), "wrong type of barrier set");
321 return static_cast<T*>(bs);
322 }
323
324 #endif // SHARE_VM_GC_SHARED_BARRIERSET_HPP