Mercurial > hg > graal-compiler
annotate src/share/vm/gc_implementation/concurrentMarkSweep/freeChunk.hpp @ 1972:f95d63e2154a
6989984: Use standard include model for Hospot
Summary: Replaced MakeDeps and the includeDB files with more standardized solutions.
Reviewed-by: coleenp, kvn, kamg
| author | stefank |
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| date | Tue, 23 Nov 2010 13:22:55 -0800 |
| parents | be3f9c242c9d |
| children | 1e3493ac2d11 |
| rev | line source |
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| 187 | 1 /* |
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2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved. |
| 187 | 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 * | |
|
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
| 187 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #ifndef SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_FREECHUNK_HPP |
| 26 #define SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_FREECHUNK_HPP | |
| 27 | |
| 28 #include "memory/allocation.hpp" | |
| 29 #include "memory/memRegion.hpp" | |
| 30 #include "oops/markOop.hpp" | |
| 31 #include "runtime/mutex.hpp" | |
| 32 #include "utilities/debug.hpp" | |
| 33 #include "utilities/globalDefinitions.hpp" | |
| 34 #include "utilities/ostream.hpp" | |
| 35 | |
| 187 | 36 // |
| 37 // Free block maintenance for Concurrent Mark Sweep Generation | |
| 38 // | |
| 39 // The main data structure for free blocks are | |
| 40 // . an indexed array of small free blocks, and | |
| 41 // . a dictionary of large free blocks | |
| 42 // | |
| 43 | |
| 44 // No virtuals in FreeChunk (don't want any vtables). | |
| 45 | |
| 46 // A FreeChunk is merely a chunk that can be in a doubly linked list | |
| 47 // and has a size field. NOTE: FreeChunks are distinguished from allocated | |
| 48 // objects in two ways (by the sweeper), depending on whether the VM is 32 or | |
| 49 // 64 bits. | |
| 50 // In 32 bits or 64 bits without CompressedOops, the second word (prev) has the | |
| 51 // LSB set to indicate a free chunk; allocated objects' klass() pointers | |
| 52 // don't have their LSB set. The corresponding bit in the CMSBitMap is | |
| 53 // set when the chunk is allocated. There are also blocks that "look free" | |
| 54 // but are not part of the free list and should not be coalesced into larger | |
| 55 // free blocks. These free blocks have their two LSB's set. | |
| 56 | |
| 57 class FreeChunk VALUE_OBJ_CLASS_SPEC { | |
| 58 friend class VMStructs; | |
| 59 // For 64 bit compressed oops, the markOop encodes both the size and the | |
| 60 // indication that this is a FreeChunk and not an object. | |
| 61 volatile size_t _size; | |
| 62 FreeChunk* _prev; | |
| 63 FreeChunk* _next; | |
| 64 | |
| 65 markOop mark() const volatile { return (markOop)_size; } | |
| 66 void set_mark(markOop m) { _size = (size_t)m; } | |
| 67 | |
| 68 public: | |
| 69 NOT_PRODUCT(static const size_t header_size();) | |
| 70 | |
| 71 // Returns "true" if the address indicates that the block represents | |
| 72 // a free chunk. | |
| 73 static bool indicatesFreeChunk(const HeapWord* addr) { | |
| 74 // Force volatile read from addr because value might change between | |
| 75 // calls. We really want the read of _mark and _prev from this pointer | |
| 76 // to be volatile but making the fields volatile causes all sorts of | |
| 77 // compilation errors. | |
| 78 return ((volatile FreeChunk*)addr)->isFree(); | |
| 79 } | |
| 80 | |
| 81 bool isFree() const volatile { | |
| 82 LP64_ONLY(if (UseCompressedOops) return mark()->is_cms_free_chunk(); else) | |
| 83 return (((intptr_t)_prev) & 0x1) == 0x1; | |
| 84 } | |
| 85 bool cantCoalesce() const { | |
| 86 assert(isFree(), "can't get coalesce bit on not free"); | |
| 87 return (((intptr_t)_prev) & 0x2) == 0x2; | |
| 88 } | |
| 89 void dontCoalesce() { | |
| 90 // the block should be free | |
| 91 assert(isFree(), "Should look like a free block"); | |
| 92 _prev = (FreeChunk*)(((intptr_t)_prev) | 0x2); | |
| 93 } | |
| 94 FreeChunk* prev() const { | |
| 95 return (FreeChunk*)(((intptr_t)_prev) & ~(0x3)); | |
| 96 } | |
| 97 | |
| 98 debug_only(void* prev_addr() const { return (void*)&_prev; }) | |
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99 debug_only(void* next_addr() const { return (void*)&_next; }) |
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100 debug_only(void* size_addr() const { return (void*)&_size; }) |
| 187 | 101 |
| 102 size_t size() const volatile { | |
| 103 LP64_ONLY(if (UseCompressedOops) return mark()->get_size(); else ) | |
| 104 return _size; | |
| 105 } | |
| 106 void setSize(size_t sz) { | |
| 107 LP64_ONLY(if (UseCompressedOops) set_mark(markOopDesc::set_size_and_free(sz)); else ) | |
| 108 _size = sz; | |
| 109 } | |
| 110 | |
| 111 FreeChunk* next() const { return _next; } | |
| 112 | |
| 113 void linkAfter(FreeChunk* ptr) { | |
| 114 linkNext(ptr); | |
| 115 if (ptr != NULL) ptr->linkPrev(this); | |
| 116 } | |
| 117 void linkAfterNonNull(FreeChunk* ptr) { | |
| 118 assert(ptr != NULL, "precondition violation"); | |
| 119 linkNext(ptr); | |
| 120 ptr->linkPrev(this); | |
| 121 } | |
| 122 void linkNext(FreeChunk* ptr) { _next = ptr; } | |
| 123 void linkPrev(FreeChunk* ptr) { | |
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124 LP64_ONLY(if (UseCompressedOops) _prev = ptr; else) |
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125 _prev = (FreeChunk*)((intptr_t)ptr | 0x1); |
| 187 | 126 } |
| 127 void clearPrev() { _prev = NULL; } | |
| 128 void clearNext() { _next = NULL; } | |
| 129 void markNotFree() { | |
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130 // Set _prev (klass) to null before (if) clearing the mark word below |
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131 _prev = NULL; |
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132 #ifdef _LP64 |
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133 if (UseCompressedOops) { |
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134 OrderAccess::storestore(); |
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135 set_mark(markOopDesc::prototype()); |
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136 } |
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137 #endif |
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138 assert(!isFree(), "Error"); |
| 187 | 139 } |
| 140 | |
| 141 // Return the address past the end of this chunk | |
| 142 HeapWord* end() const { return ((HeapWord*) this) + size(); } | |
| 143 | |
| 144 // debugging | |
| 145 void verify() const PRODUCT_RETURN; | |
| 146 void verifyList() const PRODUCT_RETURN; | |
| 147 void mangleAllocated(size_t size) PRODUCT_RETURN; | |
| 148 void mangleFreed(size_t size) PRODUCT_RETURN; | |
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149 |
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150 void print_on(outputStream* st); |
| 187 | 151 }; |
| 152 | |
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153 extern size_t MinChunkSize; |
| 187 | 154 |
| 1972 | 155 |
| 156 #endif // SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_FREECHUNK_HPP |