Tue, 19 May 2015 15:49:27 +0200
8061715: gc/g1/TestShrinkAuxiliaryData15.java fails with java.lang.RuntimeException: heap decommit failed - after > before
Summary: added WhiteBox methods to count regions and exact aux data sizes
Reviewed-by: jwilhelm, brutisso
1 /*
2 * Copyright (c) 2014, 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.
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23 */
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCATOR_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCATOR_HPP
28 #include "gc_implementation/g1/g1AllocationContext.hpp"
29 #include "gc_implementation/g1/g1AllocRegion.hpp"
30 #include "gc_implementation/g1/g1InCSetState.hpp"
31 #include "gc_implementation/shared/parGCAllocBuffer.hpp"
33 // Base class for G1 allocators.
34 class G1Allocator : public CHeapObj<mtGC> {
35 friend class VMStructs;
36 protected:
37 G1CollectedHeap* _g1h;
39 // Outside of GC pauses, the number of bytes used in all regions other
40 // than the current allocation region.
41 size_t _summary_bytes_used;
43 public:
44 G1Allocator(G1CollectedHeap* heap) :
45 _g1h(heap), _summary_bytes_used(0) { }
47 static G1Allocator* create_allocator(G1CollectedHeap* g1h);
49 virtual void init_mutator_alloc_region() = 0;
50 virtual void release_mutator_alloc_region() = 0;
52 virtual void init_gc_alloc_regions(EvacuationInfo& evacuation_info) = 0;
53 virtual void release_gc_alloc_regions(uint no_of_gc_workers, EvacuationInfo& evacuation_info) = 0;
54 virtual void abandon_gc_alloc_regions() = 0;
56 virtual MutatorAllocRegion* mutator_alloc_region(AllocationContext_t context) = 0;
57 virtual SurvivorGCAllocRegion* survivor_gc_alloc_region(AllocationContext_t context) = 0;
58 virtual OldGCAllocRegion* old_gc_alloc_region(AllocationContext_t context) = 0;
59 virtual size_t used() = 0;
60 virtual bool is_retained_old_region(HeapRegion* hr) = 0;
62 void reuse_retained_old_region(EvacuationInfo& evacuation_info,
63 OldGCAllocRegion* old,
64 HeapRegion** retained);
66 size_t used_unlocked() const {
67 return _summary_bytes_used;
68 }
70 void increase_used(size_t bytes) {
71 _summary_bytes_used += bytes;
72 }
74 void decrease_used(size_t bytes) {
75 assert(_summary_bytes_used >= bytes,
76 err_msg("invariant: _summary_bytes_used: "SIZE_FORMAT" should be >= bytes: "SIZE_FORMAT,
77 _summary_bytes_used, bytes));
78 _summary_bytes_used -= bytes;
79 }
81 void set_used(size_t bytes) {
82 _summary_bytes_used = bytes;
83 }
85 virtual HeapRegion* new_heap_region(uint hrs_index,
86 G1BlockOffsetSharedArray* sharedOffsetArray,
87 MemRegion mr) {
88 return new HeapRegion(hrs_index, sharedOffsetArray, mr);
89 }
90 };
92 // The default allocator for G1.
93 class G1DefaultAllocator : public G1Allocator {
94 protected:
95 // Alloc region used to satisfy mutator allocation requests.
96 MutatorAllocRegion _mutator_alloc_region;
98 // Alloc region used to satisfy allocation requests by the GC for
99 // survivor objects.
100 SurvivorGCAllocRegion _survivor_gc_alloc_region;
102 // Alloc region used to satisfy allocation requests by the GC for
103 // old objects.
104 OldGCAllocRegion _old_gc_alloc_region;
106 HeapRegion* _retained_old_gc_alloc_region;
107 public:
108 G1DefaultAllocator(G1CollectedHeap* heap) : G1Allocator(heap), _retained_old_gc_alloc_region(NULL) { }
110 virtual void init_mutator_alloc_region();
111 virtual void release_mutator_alloc_region();
113 virtual void init_gc_alloc_regions(EvacuationInfo& evacuation_info);
114 virtual void release_gc_alloc_regions(uint no_of_gc_workers, EvacuationInfo& evacuation_info);
115 virtual void abandon_gc_alloc_regions();
117 virtual bool is_retained_old_region(HeapRegion* hr) {
118 return _retained_old_gc_alloc_region == hr;
119 }
121 virtual MutatorAllocRegion* mutator_alloc_region(AllocationContext_t context) {
122 return &_mutator_alloc_region;
123 }
125 virtual SurvivorGCAllocRegion* survivor_gc_alloc_region(AllocationContext_t context) {
126 return &_survivor_gc_alloc_region;
127 }
129 virtual OldGCAllocRegion* old_gc_alloc_region(AllocationContext_t context) {
130 return &_old_gc_alloc_region;
131 }
133 virtual size_t used() {
134 assert(Heap_lock->owner() != NULL,
135 "Should be owned on this thread's behalf.");
136 size_t result = _summary_bytes_used;
138 // Read only once in case it is set to NULL concurrently
139 HeapRegion* hr = mutator_alloc_region(AllocationContext::current())->get();
140 if (hr != NULL) {
141 result += hr->used();
142 }
143 return result;
144 }
145 };
147 class G1ParGCAllocBuffer: public ParGCAllocBuffer {
148 private:
149 bool _retired;
151 public:
152 G1ParGCAllocBuffer(size_t gclab_word_size);
153 virtual ~G1ParGCAllocBuffer() {
154 guarantee(_retired, "Allocation buffer has not been retired");
155 }
157 virtual void set_buf(HeapWord* buf) {
158 ParGCAllocBuffer::set_buf(buf);
159 _retired = false;
160 }
162 virtual void retire(bool end_of_gc, bool retain) {
163 if (_retired) {
164 return;
165 }
166 ParGCAllocBuffer::retire(end_of_gc, retain);
167 _retired = true;
168 }
169 };
171 class G1ParGCAllocator : public CHeapObj<mtGC> {
172 friend class G1ParScanThreadState;
173 protected:
174 G1CollectedHeap* _g1h;
176 // The survivor alignment in effect in bytes.
177 // == 0 : don't align survivors
178 // != 0 : align survivors to that alignment
179 // These values were chosen to favor the non-alignment case since some
180 // architectures have a special compare against zero instructions.
181 const uint _survivor_alignment_bytes;
183 size_t _alloc_buffer_waste;
184 size_t _undo_waste;
186 void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; }
187 void add_to_undo_waste(size_t waste) { _undo_waste += waste; }
189 virtual void retire_alloc_buffers() = 0;
190 virtual G1ParGCAllocBuffer* alloc_buffer(InCSetState dest, AllocationContext_t context) = 0;
192 // Calculate the survivor space object alignment in bytes. Returns that or 0 if
193 // there are no restrictions on survivor alignment.
194 static uint calc_survivor_alignment_bytes() {
195 assert(SurvivorAlignmentInBytes >= ObjectAlignmentInBytes, "sanity");
196 if (SurvivorAlignmentInBytes == ObjectAlignmentInBytes) {
197 // No need to align objects in the survivors differently, return 0
198 // which means "survivor alignment is not used".
199 return 0;
200 } else {
201 assert(SurvivorAlignmentInBytes > 0, "sanity");
202 return SurvivorAlignmentInBytes;
203 }
204 }
206 public:
207 G1ParGCAllocator(G1CollectedHeap* g1h) :
208 _g1h(g1h), _survivor_alignment_bytes(calc_survivor_alignment_bytes()),
209 _alloc_buffer_waste(0), _undo_waste(0) {
210 }
212 static G1ParGCAllocator* create_allocator(G1CollectedHeap* g1h);
214 size_t alloc_buffer_waste() { return _alloc_buffer_waste; }
215 size_t undo_waste() {return _undo_waste; }
217 // Allocate word_sz words in dest, either directly into the regions or by
218 // allocating a new PLAB. Returns the address of the allocated memory, NULL if
219 // not successful.
220 HeapWord* allocate_direct_or_new_plab(InCSetState dest,
221 size_t word_sz,
222 AllocationContext_t context);
224 // Allocate word_sz words in the PLAB of dest. Returns the address of the
225 // allocated memory, NULL if not successful.
226 HeapWord* plab_allocate(InCSetState dest,
227 size_t word_sz,
228 AllocationContext_t context) {
229 G1ParGCAllocBuffer* buffer = alloc_buffer(dest, context);
230 if (_survivor_alignment_bytes == 0) {
231 return buffer->allocate(word_sz);
232 } else {
233 return buffer->allocate_aligned(word_sz, _survivor_alignment_bytes);
234 }
235 }
237 HeapWord* allocate(InCSetState dest, size_t word_sz,
238 AllocationContext_t context) {
239 HeapWord* const obj = plab_allocate(dest, word_sz, context);
240 if (obj != NULL) {
241 return obj;
242 }
243 return allocate_direct_or_new_plab(dest, word_sz, context);
244 }
246 void undo_allocation(InCSetState dest, HeapWord* obj, size_t word_sz, AllocationContext_t context) {
247 if (alloc_buffer(dest, context)->contains(obj)) {
248 assert(alloc_buffer(dest, context)->contains(obj + word_sz - 1),
249 "should contain whole object");
250 alloc_buffer(dest, context)->undo_allocation(obj, word_sz);
251 } else {
252 CollectedHeap::fill_with_object(obj, word_sz);
253 add_to_undo_waste(word_sz);
254 }
255 }
256 };
258 class G1DefaultParGCAllocator : public G1ParGCAllocator {
259 G1ParGCAllocBuffer _surviving_alloc_buffer;
260 G1ParGCAllocBuffer _tenured_alloc_buffer;
261 G1ParGCAllocBuffer* _alloc_buffers[InCSetState::Num];
263 public:
264 G1DefaultParGCAllocator(G1CollectedHeap* g1h);
266 virtual G1ParGCAllocBuffer* alloc_buffer(InCSetState dest, AllocationContext_t context) {
267 assert(dest.is_valid(),
268 err_msg("Allocation buffer index out-of-bounds: " CSETSTATE_FORMAT, dest.value()));
269 assert(_alloc_buffers[dest.value()] != NULL,
270 err_msg("Allocation buffer is NULL: " CSETSTATE_FORMAT, dest.value()));
271 return _alloc_buffers[dest.value()];
272 }
274 virtual void retire_alloc_buffers() ;
275 };
277 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1ALLOCATOR_HPP