Mercurial > hg > graal-compiler
annotate src/share/vm/memory/space.hpp @ 1941:79d04223b8a5
Added caching for resolved types and resolved fields.
This is crucial, because the local load elimination will lead to wrong results, if field equality (of two RiField objects with the same object and the same RiType) is not given. The caching makes sure that the default equals implementation is sufficient.
| author | Thomas Wuerthinger <wuerthinger@ssw.jku.at> |
|---|---|
| date | Tue, 28 Dec 2010 18:33:26 +0100 |
| parents | c18cbe5936b8 |
| children | f95d63e2154a |
| rev | line source |
|---|---|
| 0 | 1 /* |
|
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
845
diff
changeset
|
2 * Copyright (c) 1997, 2009, Oracle and/or its affiliates. All rights reserved. |
| 0 | 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 * | |
|
1552
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
845
diff
changeset
|
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
845
diff
changeset
|
20 * or visit www.oracle.com if you need additional information or have any |
|
c18cbe5936b8
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
845
diff
changeset
|
21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 25 // A space is an abstraction for the "storage units" backing | |
| 26 // up the generation abstraction. It includes specific | |
| 27 // implementations for keeping track of free and used space, | |
| 28 // for iterating over objects and free blocks, etc. | |
| 29 | |
| 30 // Here's the Space hierarchy: | |
| 31 // | |
| 32 // - Space -- an asbtract base class describing a heap area | |
| 33 // - CompactibleSpace -- a space supporting compaction | |
| 34 // - CompactibleFreeListSpace -- (used for CMS generation) | |
| 35 // - ContiguousSpace -- a compactible space in which all free space | |
| 36 // is contiguous | |
| 37 // - EdenSpace -- contiguous space used as nursery | |
| 38 // - ConcEdenSpace -- contiguous space with a 'soft end safe' allocation | |
| 39 // - OffsetTableContigSpace -- contiguous space with a block offset array | |
| 40 // that allows "fast" block_start calls | |
| 41 // - TenuredSpace -- (used for TenuredGeneration) | |
| 42 // - ContigPermSpace -- an offset table contiguous space for perm gen | |
| 43 | |
| 44 // Forward decls. | |
| 45 class Space; | |
| 46 class BlockOffsetArray; | |
| 47 class BlockOffsetArrayContigSpace; | |
| 48 class Generation; | |
| 49 class CompactibleSpace; | |
| 50 class BlockOffsetTable; | |
| 51 class GenRemSet; | |
| 52 class CardTableRS; | |
| 53 class DirtyCardToOopClosure; | |
| 54 | |
| 55 // An oop closure that is circumscribed by a filtering memory region. | |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
56 class SpaceMemRegionOopsIterClosure: public OopClosure { |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
57 private: |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
58 OopClosure* _cl; |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
59 MemRegion _mr; |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
60 protected: |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
61 template <class T> void do_oop_work(T* p) { |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
62 if (_mr.contains(p)) { |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
63 _cl->do_oop(p); |
| 0 | 64 } |
| 65 } | |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
66 public: |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
67 SpaceMemRegionOopsIterClosure(OopClosure* cl, MemRegion mr): |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
68 _cl(cl), _mr(mr) {} |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
69 virtual void do_oop(oop* p); |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
70 virtual void do_oop(narrowOop* p); |
| 0 | 71 }; |
| 72 | |
| 73 // A Space describes a heap area. Class Space is an abstract | |
| 74 // base class. | |
| 75 // | |
| 76 // Space supports allocation, size computation and GC support is provided. | |
| 77 // | |
| 78 // Invariant: bottom() and end() are on page_size boundaries and | |
| 79 // bottom() <= top() <= end() | |
| 80 // top() is inclusive and end() is exclusive. | |
| 81 | |
| 82 class Space: public CHeapObj { | |
| 83 friend class VMStructs; | |
| 84 protected: | |
| 85 HeapWord* _bottom; | |
| 86 HeapWord* _end; | |
| 87 | |
| 88 // Used in support of save_marks() | |
| 89 HeapWord* _saved_mark_word; | |
| 90 | |
| 91 MemRegionClosure* _preconsumptionDirtyCardClosure; | |
| 92 | |
| 93 // A sequential tasks done structure. This supports | |
| 94 // parallel GC, where we have threads dynamically | |
| 95 // claiming sub-tasks from a larger parallel task. | |
| 96 SequentialSubTasksDone _par_seq_tasks; | |
| 97 | |
| 98 Space(): | |
| 99 _bottom(NULL), _end(NULL), _preconsumptionDirtyCardClosure(NULL) { } | |
| 100 | |
| 101 public: | |
| 102 // Accessors | |
| 103 HeapWord* bottom() const { return _bottom; } | |
| 104 HeapWord* end() const { return _end; } | |
| 105 virtual void set_bottom(HeapWord* value) { _bottom = value; } | |
| 106 virtual void set_end(HeapWord* value) { _end = value; } | |
| 107 | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
108 virtual HeapWord* saved_mark_word() const { return _saved_mark_word; } |
|
845
df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
579
diff
changeset
|
109 |
| 0 | 110 void set_saved_mark_word(HeapWord* p) { _saved_mark_word = p; } |
| 111 | |
| 112 MemRegionClosure* preconsumptionDirtyCardClosure() const { | |
| 113 return _preconsumptionDirtyCardClosure; | |
| 114 } | |
| 115 void setPreconsumptionDirtyCardClosure(MemRegionClosure* cl) { | |
| 116 _preconsumptionDirtyCardClosure = cl; | |
| 117 } | |
| 118 | |
| 119 // Returns a subregion of the space containing all the objects in | |
| 120 // the space. | |
| 121 virtual MemRegion used_region() const { return MemRegion(bottom(), end()); } | |
| 122 | |
| 123 // Returns a region that is guaranteed to contain (at least) all objects | |
| 124 // allocated at the time of the last call to "save_marks". If the space | |
| 125 // initializes its DirtyCardToOopClosure's specifying the "contig" option | |
| 126 // (that is, if the space is contiguous), then this region must contain only | |
| 127 // such objects: the memregion will be from the bottom of the region to the | |
| 128 // saved mark. Otherwise, the "obj_allocated_since_save_marks" method of | |
| 129 // the space must distiguish between objects in the region allocated before | |
| 130 // and after the call to save marks. | |
| 131 virtual MemRegion used_region_at_save_marks() const { | |
| 132 return MemRegion(bottom(), saved_mark_word()); | |
| 133 } | |
| 134 | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
135 // Initialization. |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
136 // "initialize" should be called once on a space, before it is used for |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
137 // any purpose. The "mr" arguments gives the bounds of the space, and |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
138 // the "clear_space" argument should be true unless the memory in "mr" is |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
139 // known to be zeroed. |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
140 virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space); |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
141 |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
142 // The "clear" method must be called on a region that may have |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
143 // had allocation performed in it, but is now to be considered empty. |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
144 virtual void clear(bool mangle_space); |
| 0 | 145 |
| 146 // For detecting GC bugs. Should only be called at GC boundaries, since | |
| 147 // some unused space may be used as scratch space during GC's. | |
| 148 // Default implementation does nothing. We also call this when expanding | |
| 149 // a space to satisfy an allocation request. See bug #4668531 | |
| 150 virtual void mangle_unused_area() {} | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
151 virtual void mangle_unused_area_complete() {} |
| 0 | 152 virtual void mangle_region(MemRegion mr) {} |
| 153 | |
| 154 // Testers | |
| 155 bool is_empty() const { return used() == 0; } | |
| 156 bool not_empty() const { return used() > 0; } | |
| 157 | |
| 158 // Returns true iff the given the space contains the | |
| 159 // given address as part of an allocated object. For | |
| 160 // ceratin kinds of spaces, this might be a potentially | |
| 161 // expensive operation. To prevent performance problems | |
| 162 // on account of its inadvertent use in product jvm's, | |
| 163 // we restrict its use to assertion checks only. | |
| 164 virtual bool is_in(const void* p) const; | |
| 165 | |
| 166 // Returns true iff the given reserved memory of the space contains the | |
| 167 // given address. | |
| 168 bool is_in_reserved(const void* p) const { return _bottom <= p && p < _end; } | |
| 169 | |
| 170 // Returns true iff the given block is not allocated. | |
| 171 virtual bool is_free_block(const HeapWord* p) const = 0; | |
| 172 | |
| 173 // Test whether p is double-aligned | |
| 174 static bool is_aligned(void* p) { | |
| 175 return ((intptr_t)p & (sizeof(double)-1)) == 0; | |
| 176 } | |
| 177 | |
| 178 // Size computations. Sizes are in bytes. | |
| 179 size_t capacity() const { return byte_size(bottom(), end()); } | |
| 180 virtual size_t used() const = 0; | |
| 181 virtual size_t free() const = 0; | |
| 182 | |
| 183 // Iterate over all the ref-containing fields of all objects in the | |
| 184 // space, calling "cl.do_oop" on each. Fields in objects allocated by | |
| 185 // applications of the closure are not included in the iteration. | |
| 186 virtual void oop_iterate(OopClosure* cl); | |
| 187 | |
| 188 // Same as above, restricted to the intersection of a memory region and | |
| 189 // the space. Fields in objects allocated by applications of the closure | |
| 190 // are not included in the iteration. | |
| 191 virtual void oop_iterate(MemRegion mr, OopClosure* cl) = 0; | |
| 192 | |
| 193 // Iterate over all objects in the space, calling "cl.do_object" on | |
| 194 // each. Objects allocated by applications of the closure are not | |
| 195 // included in the iteration. | |
| 196 virtual void object_iterate(ObjectClosure* blk) = 0; | |
|
517
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
197 // Similar to object_iterate() except only iterates over |
|
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
198 // objects whose internal references point to objects in the space. |
|
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
199 virtual void safe_object_iterate(ObjectClosure* blk) = 0; |
| 0 | 200 |
| 201 // Iterate over all objects that intersect with mr, calling "cl->do_object" | |
| 202 // on each. There is an exception to this: if this closure has already | |
| 203 // been invoked on an object, it may skip such objects in some cases. This is | |
| 204 // Most likely to happen in an "upwards" (ascending address) iteration of | |
| 205 // MemRegions. | |
| 206 virtual void object_iterate_mem(MemRegion mr, UpwardsObjectClosure* cl); | |
| 207 | |
| 208 // Iterate over as many initialized objects in the space as possible, | |
| 209 // calling "cl.do_object_careful" on each. Return NULL if all objects | |
| 210 // in the space (at the start of the iteration) were iterated over. | |
| 211 // Return an address indicating the extent of the iteration in the | |
| 212 // event that the iteration had to return because of finding an | |
| 213 // uninitialized object in the space, or if the closure "cl" | |
| 214 // signalled early termination. | |
| 215 virtual HeapWord* object_iterate_careful(ObjectClosureCareful* cl); | |
| 216 virtual HeapWord* object_iterate_careful_m(MemRegion mr, | |
| 217 ObjectClosureCareful* cl); | |
| 218 | |
| 219 // Create and return a new dirty card to oop closure. Can be | |
| 220 // overriden to return the appropriate type of closure | |
| 221 // depending on the type of space in which the closure will | |
| 222 // operate. ResourceArea allocated. | |
| 223 virtual DirtyCardToOopClosure* new_dcto_cl(OopClosure* cl, | |
| 224 CardTableModRefBS::PrecisionStyle precision, | |
| 225 HeapWord* boundary = NULL); | |
| 226 | |
| 227 // If "p" is in the space, returns the address of the start of the | |
| 228 // "block" that contains "p". We say "block" instead of "object" since | |
| 229 // some heaps may not pack objects densely; a chunk may either be an | |
| 230 // object or a non-object. If "p" is not in the space, return NULL. | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
231 virtual HeapWord* block_start_const(const void* p) const = 0; |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
232 |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
233 // The non-const version may have benevolent side effects on the data |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
234 // structure supporting these calls, possibly speeding up future calls. |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
235 // The default implementation, however, is simply to call the const |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
236 // version. |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
237 inline virtual HeapWord* block_start(const void* p); |
| 0 | 238 |
| 239 // Requires "addr" to be the start of a chunk, and returns its size. | |
| 240 // "addr + size" is required to be the start of a new chunk, or the end | |
| 241 // of the active area of the heap. | |
| 242 virtual size_t block_size(const HeapWord* addr) const = 0; | |
| 243 | |
| 244 // Requires "addr" to be the start of a block, and returns "TRUE" iff | |
| 245 // the block is an object. | |
| 246 virtual bool block_is_obj(const HeapWord* addr) const = 0; | |
| 247 | |
| 248 // Requires "addr" to be the start of a block, and returns "TRUE" iff | |
| 249 // the block is an object and the object is alive. | |
| 250 virtual bool obj_is_alive(const HeapWord* addr) const; | |
| 251 | |
| 252 // Allocation (return NULL if full). Assumes the caller has established | |
| 253 // mutually exclusive access to the space. | |
| 254 virtual HeapWord* allocate(size_t word_size) = 0; | |
| 255 | |
| 256 // Allocation (return NULL if full). Enforces mutual exclusion internally. | |
| 257 virtual HeapWord* par_allocate(size_t word_size) = 0; | |
| 258 | |
| 259 // Returns true if this object has been allocated since a | |
| 260 // generation's "save_marks" call. | |
| 261 virtual bool obj_allocated_since_save_marks(const oop obj) const = 0; | |
| 262 | |
| 263 // Mark-sweep-compact support: all spaces can update pointers to objects | |
| 264 // moving as a part of compaction. | |
| 265 virtual void adjust_pointers(); | |
| 266 | |
| 267 // PrintHeapAtGC support | |
| 268 virtual void print() const; | |
| 269 virtual void print_on(outputStream* st) const; | |
| 270 virtual void print_short() const; | |
| 271 virtual void print_short_on(outputStream* st) const; | |
| 272 | |
| 273 | |
| 274 // Accessor for parallel sequential tasks. | |
| 275 SequentialSubTasksDone* par_seq_tasks() { return &_par_seq_tasks; } | |
| 276 | |
| 277 // IF "this" is a ContiguousSpace, return it, else return NULL. | |
| 278 virtual ContiguousSpace* toContiguousSpace() { | |
| 279 return NULL; | |
| 280 } | |
| 281 | |
| 282 // Debugging | |
| 283 virtual void verify(bool allow_dirty) const = 0; | |
| 284 }; | |
| 285 | |
| 286 // A MemRegionClosure (ResourceObj) whose "do_MemRegion" function applies an | |
| 287 // OopClosure to (the addresses of) all the ref-containing fields that could | |
| 288 // be modified by virtue of the given MemRegion being dirty. (Note that | |
| 289 // because of the imprecise nature of the write barrier, this may iterate | |
| 290 // over oops beyond the region.) | |
| 291 // This base type for dirty card to oop closures handles memory regions | |
| 292 // in non-contiguous spaces with no boundaries, and should be sub-classed | |
| 293 // to support other space types. See ContiguousDCTOC for a sub-class | |
| 294 // that works with ContiguousSpaces. | |
| 295 | |
| 296 class DirtyCardToOopClosure: public MemRegionClosureRO { | |
| 297 protected: | |
| 298 OopClosure* _cl; | |
| 299 Space* _sp; | |
| 300 CardTableModRefBS::PrecisionStyle _precision; | |
| 301 HeapWord* _boundary; // If non-NULL, process only non-NULL oops | |
| 302 // pointing below boundary. | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
303 HeapWord* _min_done; // ObjHeadPreciseArray precision requires |
| 0 | 304 // a downwards traversal; this is the |
| 305 // lowest location already done (or, | |
| 306 // alternatively, the lowest address that | |
| 307 // shouldn't be done again. NULL means infinity.) | |
| 308 NOT_PRODUCT(HeapWord* _last_bottom;) | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
309 NOT_PRODUCT(HeapWord* _last_explicit_min_done;) |
| 0 | 310 |
| 311 // Get the actual top of the area on which the closure will | |
| 312 // operate, given where the top is assumed to be (the end of the | |
| 313 // memory region passed to do_MemRegion) and where the object | |
| 314 // at the top is assumed to start. For example, an object may | |
| 315 // start at the top but actually extend past the assumed top, | |
| 316 // in which case the top becomes the end of the object. | |
| 317 virtual HeapWord* get_actual_top(HeapWord* top, HeapWord* top_obj); | |
| 318 | |
| 319 // Walk the given memory region from bottom to (actual) top | |
| 320 // looking for objects and applying the oop closure (_cl) to | |
| 321 // them. The base implementation of this treats the area as | |
| 322 // blocks, where a block may or may not be an object. Sub- | |
| 323 // classes should override this to provide more accurate | |
| 324 // or possibly more efficient walking. | |
| 325 virtual void walk_mem_region(MemRegion mr, HeapWord* bottom, HeapWord* top); | |
| 326 | |
| 327 public: | |
| 328 DirtyCardToOopClosure(Space* sp, OopClosure* cl, | |
| 329 CardTableModRefBS::PrecisionStyle precision, | |
| 330 HeapWord* boundary) : | |
| 331 _sp(sp), _cl(cl), _precision(precision), _boundary(boundary), | |
| 332 _min_done(NULL) { | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
333 NOT_PRODUCT(_last_bottom = NULL); |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
334 NOT_PRODUCT(_last_explicit_min_done = NULL); |
| 0 | 335 } |
| 336 | |
| 337 void do_MemRegion(MemRegion mr); | |
| 338 | |
| 339 void set_min_done(HeapWord* min_done) { | |
| 340 _min_done = min_done; | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
341 NOT_PRODUCT(_last_explicit_min_done = _min_done); |
| 0 | 342 } |
| 343 #ifndef PRODUCT | |
| 344 void set_last_bottom(HeapWord* last_bottom) { | |
| 345 _last_bottom = last_bottom; | |
| 346 } | |
| 347 #endif | |
| 348 }; | |
| 349 | |
| 350 // A structure to represent a point at which objects are being copied | |
| 351 // during compaction. | |
| 352 class CompactPoint : public StackObj { | |
| 353 public: | |
| 354 Generation* gen; | |
| 355 CompactibleSpace* space; | |
| 356 HeapWord* threshold; | |
| 357 CompactPoint(Generation* _gen, CompactibleSpace* _space, | |
| 358 HeapWord* _threshold) : | |
| 359 gen(_gen), space(_space), threshold(_threshold) {} | |
| 360 }; | |
| 361 | |
| 362 | |
| 363 // A space that supports compaction operations. This is usually, but not | |
| 364 // necessarily, a space that is normally contiguous. But, for example, a | |
| 365 // free-list-based space whose normal collection is a mark-sweep without | |
| 366 // compaction could still support compaction in full GC's. | |
| 367 | |
| 368 class CompactibleSpace: public Space { | |
| 369 friend class VMStructs; | |
| 370 friend class CompactibleFreeListSpace; | |
| 371 friend class CompactingPermGenGen; | |
| 372 friend class CMSPermGenGen; | |
| 373 private: | |
| 374 HeapWord* _compaction_top; | |
| 375 CompactibleSpace* _next_compaction_space; | |
| 376 | |
| 377 public: | |
|
347
60fb9c4db4e6
6718086: CMS assert: _concurrent_iteration_safe_limit update missed
ysr
parents:
342
diff
changeset
|
378 CompactibleSpace() : |
|
60fb9c4db4e6
6718086: CMS assert: _concurrent_iteration_safe_limit update missed
ysr
parents:
342
diff
changeset
|
379 _compaction_top(NULL), _next_compaction_space(NULL) {} |
|
60fb9c4db4e6
6718086: CMS assert: _concurrent_iteration_safe_limit update missed
ysr
parents:
342
diff
changeset
|
380 |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
381 virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space); |
| 356 | 382 virtual void clear(bool mangle_space); |
| 0 | 383 |
| 384 // Used temporarily during a compaction phase to hold the value | |
| 385 // top should have when compaction is complete. | |
| 386 HeapWord* compaction_top() const { return _compaction_top; } | |
| 387 | |
| 388 void set_compaction_top(HeapWord* value) { | |
| 389 assert(value == NULL || (value >= bottom() && value <= end()), | |
| 390 "should point inside space"); | |
| 391 _compaction_top = value; | |
| 392 } | |
| 393 | |
| 394 // Perform operations on the space needed after a compaction | |
| 395 // has been performed. | |
| 396 virtual void reset_after_compaction() {} | |
| 397 | |
| 398 // Returns the next space (in the current generation) to be compacted in | |
| 399 // the global compaction order. Also is used to select the next | |
| 400 // space into which to compact. | |
| 401 | |
| 402 virtual CompactibleSpace* next_compaction_space() const { | |
| 403 return _next_compaction_space; | |
| 404 } | |
| 405 | |
| 406 void set_next_compaction_space(CompactibleSpace* csp) { | |
| 407 _next_compaction_space = csp; | |
| 408 } | |
| 409 | |
| 410 // MarkSweep support phase2 | |
| 411 | |
| 412 // Start the process of compaction of the current space: compute | |
| 413 // post-compaction addresses, and insert forwarding pointers. The fields | |
| 414 // "cp->gen" and "cp->compaction_space" are the generation and space into | |
| 415 // which we are currently compacting. This call updates "cp" as necessary, | |
| 416 // and leaves the "compaction_top" of the final value of | |
| 417 // "cp->compaction_space" up-to-date. Offset tables may be updated in | |
| 418 // this phase as if the final copy had occurred; if so, "cp->threshold" | |
| 419 // indicates when the next such action should be taken. | |
| 420 virtual void prepare_for_compaction(CompactPoint* cp); | |
| 421 // MarkSweep support phase3 | |
| 422 virtual void adjust_pointers(); | |
| 423 // MarkSweep support phase4 | |
| 424 virtual void compact(); | |
| 425 | |
| 426 // The maximum percentage of objects that can be dead in the compacted | |
| 427 // live part of a compacted space ("deadwood" support.) | |
| 438 | 428 virtual size_t allowed_dead_ratio() const { return 0; }; |
| 0 | 429 |
| 430 // Some contiguous spaces may maintain some data structures that should | |
| 431 // be updated whenever an allocation crosses a boundary. This function | |
| 432 // returns the first such boundary. | |
| 433 // (The default implementation returns the end of the space, so the | |
| 434 // boundary is never crossed.) | |
| 435 virtual HeapWord* initialize_threshold() { return end(); } | |
| 436 | |
| 437 // "q" is an object of the given "size" that should be forwarded; | |
| 438 // "cp" names the generation ("gen") and containing "this" (which must | |
| 439 // also equal "cp->space"). "compact_top" is where in "this" the | |
| 440 // next object should be forwarded to. If there is room in "this" for | |
| 441 // the object, insert an appropriate forwarding pointer in "q". | |
| 442 // If not, go to the next compaction space (there must | |
| 443 // be one, since compaction must succeed -- we go to the first space of | |
| 444 // the previous generation if necessary, updating "cp"), reset compact_top | |
| 445 // and then forward. In either case, returns the new value of "compact_top". | |
| 446 // If the forwarding crosses "cp->threshold", invokes the "cross_threhold" | |
| 447 // function of the then-current compaction space, and updates "cp->threshold | |
| 448 // accordingly". | |
| 449 virtual HeapWord* forward(oop q, size_t size, CompactPoint* cp, | |
| 450 HeapWord* compact_top); | |
| 451 | |
| 452 // Return a size with adjusments as required of the space. | |
| 453 virtual size_t adjust_object_size_v(size_t size) const { return size; } | |
| 454 | |
| 455 protected: | |
| 456 // Used during compaction. | |
| 457 HeapWord* _first_dead; | |
| 458 HeapWord* _end_of_live; | |
| 459 | |
| 460 // Minimum size of a free block. | |
| 461 virtual size_t minimum_free_block_size() const = 0; | |
| 462 | |
| 463 // This the function is invoked when an allocation of an object covering | |
| 464 // "start" to "end occurs crosses the threshold; returns the next | |
| 465 // threshold. (The default implementation does nothing.) | |
| 466 virtual HeapWord* cross_threshold(HeapWord* start, HeapWord* the_end) { | |
| 467 return end(); | |
| 468 } | |
| 469 | |
| 470 // Requires "allowed_deadspace_words > 0", that "q" is the start of a | |
| 471 // free block of the given "word_len", and that "q", were it an object, | |
| 472 // would not move if forwared. If the size allows, fill the free | |
| 473 // block with an object, to prevent excessive compaction. Returns "true" | |
| 474 // iff the free region was made deadspace, and modifies | |
| 475 // "allowed_deadspace_words" to reflect the number of available deadspace | |
| 476 // words remaining after this operation. | |
| 477 bool insert_deadspace(size_t& allowed_deadspace_words, HeapWord* q, | |
| 478 size_t word_len); | |
| 479 }; | |
| 480 | |
| 481 #define SCAN_AND_FORWARD(cp,scan_limit,block_is_obj,block_size) { \ | |
| 482 /* Compute the new addresses for the live objects and store it in the mark \ | |
| 483 * Used by universe::mark_sweep_phase2() \ | |
| 484 */ \ | |
| 485 HeapWord* compact_top; /* This is where we are currently compacting to. */ \ | |
| 486 \ | |
| 487 /* We're sure to be here before any objects are compacted into this \ | |
| 488 * space, so this is a good time to initialize this: \ | |
| 489 */ \ | |
| 490 set_compaction_top(bottom()); \ | |
| 491 \ | |
| 492 if (cp->space == NULL) { \ | |
| 493 assert(cp->gen != NULL, "need a generation"); \ | |
| 494 assert(cp->threshold == NULL, "just checking"); \ | |
| 495 assert(cp->gen->first_compaction_space() == this, "just checking"); \ | |
| 496 cp->space = cp->gen->first_compaction_space(); \ | |
| 497 compact_top = cp->space->bottom(); \ | |
| 498 cp->space->set_compaction_top(compact_top); \ | |
| 499 cp->threshold = cp->space->initialize_threshold(); \ | |
| 500 } else { \ | |
| 501 compact_top = cp->space->compaction_top(); \ | |
| 502 } \ | |
| 503 \ | |
| 504 /* We allow some amount of garbage towards the bottom of the space, so \ | |
| 505 * we don't start compacting before there is a significant gain to be made.\ | |
| 506 * Occasionally, we want to ensure a full compaction, which is determined \ | |
| 507 * by the MarkSweepAlwaysCompactCount parameter. \ | |
| 508 */ \ | |
| 509 int invocations = SharedHeap::heap()->perm_gen()->stat_record()->invocations;\ | |
| 510 bool skip_dead = ((invocations % MarkSweepAlwaysCompactCount) != 0); \ | |
| 511 \ | |
| 512 size_t allowed_deadspace = 0; \ | |
| 513 if (skip_dead) { \ | |
| 438 | 514 const size_t ratio = allowed_dead_ratio(); \ |
| 0 | 515 allowed_deadspace = (capacity() * ratio / 100) / HeapWordSize; \ |
| 516 } \ | |
| 517 \ | |
| 518 HeapWord* q = bottom(); \ | |
| 519 HeapWord* t = scan_limit(); \ | |
| 520 \ | |
| 521 HeapWord* end_of_live= q; /* One byte beyond the last byte of the last \ | |
| 522 live object. */ \ | |
| 523 HeapWord* first_dead = end();/* The first dead object. */ \ | |
| 524 LiveRange* liveRange = NULL; /* The current live range, recorded in the \ | |
| 525 first header of preceding free area. */ \ | |
| 526 _first_dead = first_dead; \ | |
| 527 \ | |
| 528 const intx interval = PrefetchScanIntervalInBytes; \ | |
| 529 \ | |
| 530 while (q < t) { \ | |
| 531 assert(!block_is_obj(q) || \ | |
| 532 oop(q)->mark()->is_marked() || oop(q)->mark()->is_unlocked() || \ | |
| 533 oop(q)->mark()->has_bias_pattern(), \ | |
| 534 "these are the only valid states during a mark sweep"); \ | |
| 535 if (block_is_obj(q) && oop(q)->is_gc_marked()) { \ | |
| 536 /* prefetch beyond q */ \ | |
| 537 Prefetch::write(q, interval); \ | |
| 538 /* size_t size = oop(q)->size(); changing this for cms for perm gen */\ | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
539 size_t size = block_size(q); \ |
| 0 | 540 compact_top = cp->space->forward(oop(q), size, cp, compact_top); \ |
| 541 q += size; \ | |
| 542 end_of_live = q; \ | |
| 543 } else { \ | |
| 544 /* run over all the contiguous dead objects */ \ | |
| 545 HeapWord* end = q; \ | |
| 546 do { \ | |
| 547 /* prefetch beyond end */ \ | |
| 548 Prefetch::write(end, interval); \ | |
| 549 end += block_size(end); \ | |
| 550 } while (end < t && (!block_is_obj(end) || !oop(end)->is_gc_marked()));\ | |
| 551 \ | |
| 552 /* see if we might want to pretend this object is alive so that \ | |
| 553 * we don't have to compact quite as often. \ | |
| 554 */ \ | |
| 555 if (allowed_deadspace > 0 && q == compact_top) { \ | |
| 556 size_t sz = pointer_delta(end, q); \ | |
| 557 if (insert_deadspace(allowed_deadspace, q, sz)) { \ | |
| 558 compact_top = cp->space->forward(oop(q), sz, cp, compact_top); \ | |
| 559 q = end; \ | |
| 560 end_of_live = end; \ | |
| 561 continue; \ | |
| 562 } \ | |
| 563 } \ | |
| 564 \ | |
| 565 /* otherwise, it really is a free region. */ \ | |
| 566 \ | |
| 567 /* for the previous LiveRange, record the end of the live objects. */ \ | |
| 568 if (liveRange) { \ | |
| 569 liveRange->set_end(q); \ | |
| 570 } \ | |
| 571 \ | |
| 572 /* record the current LiveRange object. \ | |
| 573 * liveRange->start() is overlaid on the mark word. \ | |
| 574 */ \ | |
| 575 liveRange = (LiveRange*)q; \ | |
| 576 liveRange->set_start(end); \ | |
| 577 liveRange->set_end(end); \ | |
| 578 \ | |
| 579 /* see if this is the first dead region. */ \ | |
| 580 if (q < first_dead) { \ | |
| 581 first_dead = q; \ | |
| 582 } \ | |
| 583 \ | |
| 584 /* move on to the next object */ \ | |
| 585 q = end; \ | |
| 586 } \ | |
| 587 } \ | |
| 588 \ | |
| 589 assert(q == t, "just checking"); \ | |
| 590 if (liveRange != NULL) { \ | |
| 591 liveRange->set_end(q); \ | |
| 592 } \ | |
| 593 _end_of_live = end_of_live; \ | |
| 594 if (end_of_live < first_dead) { \ | |
| 595 first_dead = end_of_live; \ | |
| 596 } \ | |
| 597 _first_dead = first_dead; \ | |
| 598 \ | |
| 599 /* save the compaction_top of the compaction space. */ \ | |
| 600 cp->space->set_compaction_top(compact_top); \ | |
| 601 } | |
| 602 | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
603 #define SCAN_AND_ADJUST_POINTERS(adjust_obj_size) { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
604 /* adjust all the interior pointers to point at the new locations of objects \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
605 * Used by MarkSweep::mark_sweep_phase3() */ \ |
| 0 | 606 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
607 HeapWord* q = bottom(); \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
608 HeapWord* t = _end_of_live; /* Established by "prepare_for_compaction". */ \ |
| 0 | 609 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
610 assert(_first_dead <= _end_of_live, "Stands to reason, no?"); \ |
| 0 | 611 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
612 if (q < t && _first_dead > q && \ |
| 0 | 613 !oop(q)->is_gc_marked()) { \ |
| 614 /* we have a chunk of the space which hasn't moved and we've \ | |
| 615 * reinitialized the mark word during the previous pass, so we can't \ | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
616 * use is_gc_marked for the traversal. */ \ |
| 0 | 617 HeapWord* end = _first_dead; \ |
| 618 \ | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
619 while (q < end) { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
620 /* I originally tried to conjoin "block_start(q) == q" to the \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
621 * assertion below, but that doesn't work, because you can't \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
622 * accurately traverse previous objects to get to the current one \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
623 * after their pointers (including pointers into permGen) have been \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
624 * updated, until the actual compaction is done. dld, 4/00 */ \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
625 assert(block_is_obj(q), \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
626 "should be at block boundaries, and should be looking at objs"); \ |
| 0 | 627 \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
628 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::track_interior_pointers(oop(q))); \ |
| 0 | 629 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
630 /* point all the oops to the new location */ \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
631 size_t size = oop(q)->adjust_pointers(); \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
632 size = adjust_obj_size(size); \ |
| 0 | 633 \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
634 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::check_interior_pointers()); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
635 \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
636 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::validate_live_oop(oop(q), size)); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
637 \ |
| 0 | 638 q += size; \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
639 } \ |
| 0 | 640 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
641 if (_first_dead == t) { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
642 q = t; \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
643 } else { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
644 /* $$$ This is funky. Using this to read the previously written \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
645 * LiveRange. See also use below. */ \ |
| 0 | 646 q = (HeapWord*)oop(_first_dead)->mark()->decode_pointer(); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
647 } \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
648 } \ |
| 0 | 649 \ |
| 650 const intx interval = PrefetchScanIntervalInBytes; \ | |
| 651 \ | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
652 debug_only(HeapWord* prev_q = NULL); \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
653 while (q < t) { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
654 /* prefetch beyond q */ \ |
| 0 | 655 Prefetch::write(q, interval); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
656 if (oop(q)->is_gc_marked()) { \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
657 /* q is alive */ \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
658 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::track_interior_pointers(oop(q))); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
659 /* point all the oops to the new location */ \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
660 size_t size = oop(q)->adjust_pointers(); \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
661 size = adjust_obj_size(size); \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
662 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::check_interior_pointers()); \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
663 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::validate_live_oop(oop(q), size)); \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
664 debug_only(prev_q = q); \ |
| 0 | 665 q += size; \ |
| 356 | 666 } else { \ |
| 667 /* q is not a live object, so its mark should point at the next \ | |
| 668 * live object */ \ | |
| 669 debug_only(prev_q = q); \ | |
| 670 q = (HeapWord*) oop(q)->mark()->decode_pointer(); \ | |
| 671 assert(q > prev_q, "we should be moving forward through memory"); \ | |
| 672 } \ | |
| 673 } \ | |
| 0 | 674 \ |
| 356 | 675 assert(q == t, "just checking"); \ |
| 0 | 676 } |
| 677 | |
| 356 | 678 #define SCAN_AND_COMPACT(obj_size) { \ |
| 0 | 679 /* Copy all live objects to their new location \ |
| 356 | 680 * Used by MarkSweep::mark_sweep_phase4() */ \ |
| 0 | 681 \ |
| 356 | 682 HeapWord* q = bottom(); \ |
| 683 HeapWord* const t = _end_of_live; \ | |
| 684 debug_only(HeapWord* prev_q = NULL); \ | |
| 0 | 685 \ |
| 356 | 686 if (q < t && _first_dead > q && \ |
| 0 | 687 !oop(q)->is_gc_marked()) { \ |
| 356 | 688 debug_only( \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
689 /* we have a chunk of the space which hasn't moved and we've reinitialized \ |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
690 * the mark word during the previous pass, so we can't use is_gc_marked for \ |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
691 * the traversal. */ \ |
| 356 | 692 HeapWord* const end = _first_dead; \ |
| 693 \ | |
| 694 while (q < end) { \ | |
| 0 | 695 size_t size = obj_size(q); \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
696 assert(!oop(q)->is_gc_marked(), \ |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
697 "should be unmarked (special dense prefix handling)"); \ |
| 356 | 698 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::live_oop_moved_to(q, size, q)); \ |
| 699 debug_only(prev_q = q); \ | |
| 0 | 700 q += size; \ |
| 356 | 701 } \ |
| 702 ) /* debug_only */ \ | |
| 703 \ | |
| 704 if (_first_dead == t) { \ | |
| 705 q = t; \ | |
| 706 } else { \ | |
| 707 /* $$$ Funky */ \ | |
| 708 q = (HeapWord*) oop(_first_dead)->mark()->decode_pointer(); \ | |
| 709 } \ | |
| 710 } \ | |
| 0 | 711 \ |
| 356 | 712 const intx scan_interval = PrefetchScanIntervalInBytes; \ |
| 713 const intx copy_interval = PrefetchCopyIntervalInBytes; \ | |
| 714 while (q < t) { \ | |
| 715 if (!oop(q)->is_gc_marked()) { \ | |
| 716 /* mark is pointer to next marked oop */ \ | |
| 717 debug_only(prev_q = q); \ | |
| 718 q = (HeapWord*) oop(q)->mark()->decode_pointer(); \ | |
| 719 assert(q > prev_q, "we should be moving forward through memory"); \ | |
| 720 } else { \ | |
| 721 /* prefetch beyond q */ \ | |
| 0 | 722 Prefetch::read(q, scan_interval); \ |
| 723 \ | |
| 724 /* size and destination */ \ | |
| 725 size_t size = obj_size(q); \ | |
| 726 HeapWord* compaction_top = (HeapWord*)oop(q)->forwardee(); \ | |
| 727 \ | |
| 356 | 728 /* prefetch beyond compaction_top */ \ |
| 0 | 729 Prefetch::write(compaction_top, copy_interval); \ |
| 730 \ | |
| 356 | 731 /* copy object and reinit its mark */ \ |
|
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
732 VALIDATE_MARK_SWEEP_ONLY(MarkSweep::live_oop_moved_to(q, size, \ |
|
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
733 compaction_top)); \ |
| 356 | 734 assert(q != compaction_top, "everything in this pass should be moving"); \ |
| 735 Copy::aligned_conjoint_words(q, compaction_top, size); \ | |
| 736 oop(compaction_top)->init_mark(); \ | |
| 737 assert(oop(compaction_top)->klass() != NULL, "should have a class"); \ | |
| 0 | 738 \ |
| 356 | 739 debug_only(prev_q = q); \ |
| 0 | 740 q += size; \ |
| 356 | 741 } \ |
| 742 } \ | |
| 0 | 743 \ |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
744 /* Let's remember if we were empty before we did the compaction. */ \ |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
745 bool was_empty = used_region().is_empty(); \ |
| 0 | 746 /* Reset space after compaction is complete */ \ |
| 356 | 747 reset_after_compaction(); \ |
| 0 | 748 /* We do this clear, below, since it has overloaded meanings for some */ \ |
| 749 /* space subtypes. For example, OffsetTableContigSpace's that were */ \ | |
| 750 /* compacted into will have had their offset table thresholds updated */ \ | |
| 751 /* continuously, but those that weren't need to have their thresholds */ \ | |
| 752 /* re-initialized. Also mangles unused area for debugging. */ \ | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
753 if (used_region().is_empty()) { \ |
| 356 | 754 if (!was_empty) clear(SpaceDecorator::Mangle); \ |
| 0 | 755 } else { \ |
| 756 if (ZapUnusedHeapArea) mangle_unused_area(); \ | |
| 757 } \ | |
| 758 } | |
| 759 | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
760 class GenSpaceMangler; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
761 |
| 0 | 762 // A space in which the free area is contiguous. It therefore supports |
| 763 // faster allocation, and compaction. | |
| 764 class ContiguousSpace: public CompactibleSpace { | |
| 765 friend class OneContigSpaceCardGeneration; | |
| 766 friend class VMStructs; | |
| 767 protected: | |
| 768 HeapWord* _top; | |
| 769 HeapWord* _concurrent_iteration_safe_limit; | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
770 // A helper for mangling the unused area of the space in debug builds. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
771 GenSpaceMangler* _mangler; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
772 |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
773 GenSpaceMangler* mangler() { return _mangler; } |
| 0 | 774 |
| 775 // Allocation helpers (return NULL if full). | |
| 776 inline HeapWord* allocate_impl(size_t word_size, HeapWord* end_value); | |
| 777 inline HeapWord* par_allocate_impl(size_t word_size, HeapWord* end_value); | |
| 778 | |
| 779 public: | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
780 ContiguousSpace(); |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
781 ~ContiguousSpace(); |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
782 |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
783 virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space); |
| 356 | 784 virtual void clear(bool mangle_space); |
| 0 | 785 |
| 786 // Accessors | |
| 787 HeapWord* top() const { return _top; } | |
| 788 void set_top(HeapWord* value) { _top = value; } | |
| 789 | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
790 virtual void set_saved_mark() { _saved_mark_word = top(); } |
|
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
791 void reset_saved_mark() { _saved_mark_word = bottom(); } |
| 0 | 792 |
| 793 WaterMark bottom_mark() { return WaterMark(this, bottom()); } | |
| 794 WaterMark top_mark() { return WaterMark(this, top()); } | |
| 795 WaterMark saved_mark() { return WaterMark(this, saved_mark_word()); } | |
| 796 bool saved_mark_at_top() const { return saved_mark_word() == top(); } | |
| 797 | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
798 // In debug mode mangle (write it with a particular bit |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
799 // pattern) the unused part of a space. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
800 |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
801 // Used to save the an address in a space for later use during mangling. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
802 void set_top_for_allocations(HeapWord* v) PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
803 // Used to save the space's current top for later use during mangling. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
804 void set_top_for_allocations() PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
805 |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
806 // Mangle regions in the space from the current top up to the |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
807 // previously mangled part of the space. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
808 void mangle_unused_area() PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
809 // Mangle [top, end) |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
810 void mangle_unused_area_complete() PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
811 // Mangle the given MemRegion. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
812 void mangle_region(MemRegion mr) PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
813 |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
814 // Do some sparse checking on the area that should have been mangled. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
815 void check_mangled_unused_area(HeapWord* limit) PRODUCT_RETURN; |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
816 // Check the complete area that should have been mangled. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
817 // This code may be NULL depending on the macro DEBUG_MANGLING. |
|
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
818 void check_mangled_unused_area_complete() PRODUCT_RETURN; |
| 0 | 819 |
| 820 // Size computations: sizes in bytes. | |
| 821 size_t capacity() const { return byte_size(bottom(), end()); } | |
| 822 size_t used() const { return byte_size(bottom(), top()); } | |
| 823 size_t free() const { return byte_size(top(), end()); } | |
| 824 | |
| 825 // Override from space. | |
| 826 bool is_in(const void* p) const; | |
| 827 | |
| 828 virtual bool is_free_block(const HeapWord* p) const; | |
| 829 | |
| 830 // In a contiguous space we have a more obvious bound on what parts | |
| 831 // contain objects. | |
| 832 MemRegion used_region() const { return MemRegion(bottom(), top()); } | |
| 833 | |
| 834 MemRegion used_region_at_save_marks() const { | |
| 835 return MemRegion(bottom(), saved_mark_word()); | |
| 836 } | |
| 837 | |
| 838 // Allocation (return NULL if full) | |
| 839 virtual HeapWord* allocate(size_t word_size); | |
| 840 virtual HeapWord* par_allocate(size_t word_size); | |
| 841 | |
| 842 virtual bool obj_allocated_since_save_marks(const oop obj) const { | |
| 843 return (HeapWord*)obj >= saved_mark_word(); | |
| 844 } | |
| 845 | |
| 846 // Iteration | |
| 847 void oop_iterate(OopClosure* cl); | |
| 848 void oop_iterate(MemRegion mr, OopClosure* cl); | |
| 849 void object_iterate(ObjectClosure* blk); | |
|
517
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
850 // For contiguous spaces this method will iterate safely over objects |
|
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
851 // in the space (i.e., between bottom and top) when at a safepoint. |
|
e9be0e04635a
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
438
diff
changeset
|
852 void safe_object_iterate(ObjectClosure* blk); |
| 0 | 853 void object_iterate_mem(MemRegion mr, UpwardsObjectClosure* cl); |
| 854 // iterates on objects up to the safe limit | |
| 855 HeapWord* object_iterate_careful(ObjectClosureCareful* cl); | |
| 856 inline HeapWord* concurrent_iteration_safe_limit(); | |
| 857 // changes the safe limit, all objects from bottom() to the new | |
| 858 // limit should be properly initialized | |
| 859 inline void set_concurrent_iteration_safe_limit(HeapWord* new_limit); | |
| 860 | |
| 861 #ifndef SERIALGC | |
| 862 // In support of parallel oop_iterate. | |
| 863 #define ContigSpace_PAR_OOP_ITERATE_DECL(OopClosureType, nv_suffix) \ | |
| 864 void par_oop_iterate(MemRegion mr, OopClosureType* blk); | |
| 865 | |
| 866 ALL_PAR_OOP_ITERATE_CLOSURES(ContigSpace_PAR_OOP_ITERATE_DECL) | |
| 867 #undef ContigSpace_PAR_OOP_ITERATE_DECL | |
| 868 #endif // SERIALGC | |
| 869 | |
| 870 // Compaction support | |
| 871 virtual void reset_after_compaction() { | |
| 872 assert(compaction_top() >= bottom() && compaction_top() <= end(), "should point inside space"); | |
| 873 set_top(compaction_top()); | |
| 874 // set new iteration safe limit | |
| 875 set_concurrent_iteration_safe_limit(compaction_top()); | |
| 876 } | |
| 877 virtual size_t minimum_free_block_size() const { return 0; } | |
| 878 | |
| 879 // Override. | |
| 880 DirtyCardToOopClosure* new_dcto_cl(OopClosure* cl, | |
| 881 CardTableModRefBS::PrecisionStyle precision, | |
| 882 HeapWord* boundary = NULL); | |
| 883 | |
| 884 // Apply "blk->do_oop" to the addresses of all reference fields in objects | |
| 885 // starting with the _saved_mark_word, which was noted during a generation's | |
| 886 // save_marks and is required to denote the head of an object. | |
| 887 // Fields in objects allocated by applications of the closure | |
| 888 // *are* included in the iteration. | |
| 889 // Updates _saved_mark_word to point to just after the last object | |
| 890 // iterated over. | |
| 891 #define ContigSpace_OOP_SINCE_SAVE_MARKS_DECL(OopClosureType, nv_suffix) \ | |
| 892 void oop_since_save_marks_iterate##nv_suffix(OopClosureType* blk); | |
| 893 | |
| 894 ALL_SINCE_SAVE_MARKS_CLOSURES(ContigSpace_OOP_SINCE_SAVE_MARKS_DECL) | |
| 895 #undef ContigSpace_OOP_SINCE_SAVE_MARKS_DECL | |
| 896 | |
| 897 // Same as object_iterate, but starting from "mark", which is required | |
| 898 // to denote the start of an object. Objects allocated by | |
| 899 // applications of the closure *are* included in the iteration. | |
| 900 virtual void object_iterate_from(WaterMark mark, ObjectClosure* blk); | |
| 901 | |
| 902 // Very inefficient implementation. | |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
903 virtual HeapWord* block_start_const(const void* p) const; |
| 0 | 904 size_t block_size(const HeapWord* p) const; |
| 905 // If a block is in the allocated area, it is an object. | |
| 906 bool block_is_obj(const HeapWord* p) const { return p < top(); } | |
| 907 | |
| 908 // Addresses for inlined allocation | |
| 909 HeapWord** top_addr() { return &_top; } | |
| 910 HeapWord** end_addr() { return &_end; } | |
| 911 | |
| 912 // Overrides for more efficient compaction support. | |
| 913 void prepare_for_compaction(CompactPoint* cp); | |
| 914 | |
| 915 // PrintHeapAtGC support. | |
| 916 virtual void print_on(outputStream* st) const; | |
| 917 | |
| 918 // Checked dynamic downcasts. | |
| 919 virtual ContiguousSpace* toContiguousSpace() { | |
| 920 return this; | |
| 921 } | |
| 922 | |
| 923 // Debugging | |
| 924 virtual void verify(bool allow_dirty) const; | |
| 925 | |
| 926 // Used to increase collection frequency. "factor" of 0 means entire | |
| 927 // space. | |
| 928 void allocate_temporary_filler(int factor); | |
| 929 | |
| 930 }; | |
| 931 | |
| 932 | |
| 933 // A dirty card to oop closure that does filtering. | |
| 934 // It knows how to filter out objects that are outside of the _boundary. | |
| 935 class Filtering_DCTOC : public DirtyCardToOopClosure { | |
| 936 protected: | |
| 937 // Override. | |
| 938 void walk_mem_region(MemRegion mr, | |
| 939 HeapWord* bottom, HeapWord* top); | |
| 940 | |
| 941 // Walk the given memory region, from bottom to top, applying | |
| 942 // the given oop closure to (possibly) all objects found. The | |
| 943 // given oop closure may or may not be the same as the oop | |
| 944 // closure with which this closure was created, as it may | |
| 945 // be a filtering closure which makes use of the _boundary. | |
| 946 // We offer two signatures, so the FilteringClosure static type is | |
| 947 // apparent. | |
| 948 virtual void walk_mem_region_with_cl(MemRegion mr, | |
| 949 HeapWord* bottom, HeapWord* top, | |
| 950 OopClosure* cl) = 0; | |
| 951 virtual void walk_mem_region_with_cl(MemRegion mr, | |
| 952 HeapWord* bottom, HeapWord* top, | |
| 953 FilteringClosure* cl) = 0; | |
| 954 | |
| 955 public: | |
| 956 Filtering_DCTOC(Space* sp, OopClosure* cl, | |
| 957 CardTableModRefBS::PrecisionStyle precision, | |
| 958 HeapWord* boundary) : | |
| 959 DirtyCardToOopClosure(sp, cl, precision, boundary) {} | |
| 960 }; | |
| 961 | |
| 962 // A dirty card to oop closure for contiguous spaces | |
| 963 // (ContiguousSpace and sub-classes). | |
| 964 // It is a FilteringClosure, as defined above, and it knows: | |
| 965 // | |
| 966 // 1. That the actual top of any area in a memory region | |
| 967 // contained by the space is bounded by the end of the contiguous | |
| 968 // region of the space. | |
| 969 // 2. That the space is really made up of objects and not just | |
| 970 // blocks. | |
| 971 | |
| 972 class ContiguousSpaceDCTOC : public Filtering_DCTOC { | |
| 973 protected: | |
| 974 // Overrides. | |
| 975 HeapWord* get_actual_top(HeapWord* top, HeapWord* top_obj); | |
| 976 | |
| 977 virtual void walk_mem_region_with_cl(MemRegion mr, | |
| 978 HeapWord* bottom, HeapWord* top, | |
| 979 OopClosure* cl); | |
| 980 virtual void walk_mem_region_with_cl(MemRegion mr, | |
| 981 HeapWord* bottom, HeapWord* top, | |
| 982 FilteringClosure* cl); | |
| 983 | |
| 984 public: | |
| 985 ContiguousSpaceDCTOC(ContiguousSpace* sp, OopClosure* cl, | |
| 986 CardTableModRefBS::PrecisionStyle precision, | |
| 987 HeapWord* boundary) : | |
| 988 Filtering_DCTOC(sp, cl, precision, boundary) | |
| 989 {} | |
| 990 }; | |
| 991 | |
| 992 | |
| 993 // Class EdenSpace describes eden-space in new generation. | |
| 994 | |
| 995 class DefNewGeneration; | |
| 996 | |
| 997 class EdenSpace : public ContiguousSpace { | |
| 998 friend class VMStructs; | |
| 999 private: | |
| 1000 DefNewGeneration* _gen; | |
| 1001 | |
| 1002 // _soft_end is used as a soft limit on allocation. As soft limits are | |
| 1003 // reached, the slow-path allocation code can invoke other actions and then | |
| 1004 // adjust _soft_end up to a new soft limit or to end(). | |
| 1005 HeapWord* _soft_end; | |
| 1006 | |
| 1007 public: | |
|
347
60fb9c4db4e6
6718086: CMS assert: _concurrent_iteration_safe_limit update missed
ysr
parents:
342
diff
changeset
|
1008 EdenSpace(DefNewGeneration* gen) : |
|
60fb9c4db4e6
6718086: CMS assert: _concurrent_iteration_safe_limit update missed
ysr
parents:
342
diff
changeset
|
1009 _gen(gen), _soft_end(NULL) {} |
| 0 | 1010 |
| 1011 // Get/set just the 'soft' limit. | |
| 1012 HeapWord* soft_end() { return _soft_end; } | |
| 1013 HeapWord** soft_end_addr() { return &_soft_end; } | |
| 1014 void set_soft_end(HeapWord* value) { _soft_end = value; } | |
| 1015 | |
| 1016 // Override. | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
1017 void clear(bool mangle_space); |
| 0 | 1018 |
| 1019 // Set both the 'hard' and 'soft' limits (_end and _soft_end). | |
| 1020 void set_end(HeapWord* value) { | |
| 1021 set_soft_end(value); | |
| 1022 ContiguousSpace::set_end(value); | |
| 1023 } | |
| 1024 | |
| 1025 // Allocation (return NULL if full) | |
| 1026 HeapWord* allocate(size_t word_size); | |
| 1027 HeapWord* par_allocate(size_t word_size); | |
| 1028 }; | |
| 1029 | |
| 1030 // Class ConcEdenSpace extends EdenSpace for the sake of safe | |
| 1031 // allocation while soft-end is being modified concurrently | |
| 1032 | |
| 1033 class ConcEdenSpace : public EdenSpace { | |
| 1034 public: | |
| 1035 ConcEdenSpace(DefNewGeneration* gen) : EdenSpace(gen) { } | |
| 1036 | |
| 1037 // Allocation (return NULL if full) | |
| 1038 HeapWord* par_allocate(size_t word_size); | |
| 1039 }; | |
| 1040 | |
| 1041 | |
| 1042 // A ContigSpace that Supports an efficient "block_start" operation via | |
| 1043 // a BlockOffsetArray (whose BlockOffsetSharedArray may be shared with | |
| 1044 // other spaces.) This is the abstract base class for old generation | |
| 1045 // (tenured, perm) spaces. | |
| 1046 | |
| 1047 class OffsetTableContigSpace: public ContiguousSpace { | |
| 1048 friend class VMStructs; | |
| 1049 protected: | |
| 1050 BlockOffsetArrayContigSpace _offsets; | |
| 1051 Mutex _par_alloc_lock; | |
| 1052 | |
| 1053 public: | |
| 1054 // Constructor | |
| 1055 OffsetTableContigSpace(BlockOffsetSharedArray* sharedOffsetArray, | |
| 1056 MemRegion mr); | |
| 1057 | |
| 1058 void set_bottom(HeapWord* value); | |
| 1059 void set_end(HeapWord* value); | |
| 1060 | |
|
263
12eea04c8b06
6672698: mangle_unused_area() should not remangle the entire heap at each collection.
jmasa
parents:
113
diff
changeset
|
1061 void clear(bool mangle_space); |
| 0 | 1062 |
|
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
1063 inline HeapWord* block_start_const(const void* p) const; |
| 0 | 1064 |
| 1065 // Add offset table update. | |
| 1066 virtual inline HeapWord* allocate(size_t word_size); | |
| 1067 inline HeapWord* par_allocate(size_t word_size); | |
| 1068 | |
| 1069 // MarkSweep support phase3 | |
| 1070 virtual HeapWord* initialize_threshold(); | |
| 1071 virtual HeapWord* cross_threshold(HeapWord* start, HeapWord* end); | |
| 1072 | |
| 1073 virtual void print_on(outputStream* st) const; | |
| 1074 | |
| 1075 // Debugging | |
| 1076 void verify(bool allow_dirty) const; | |
| 1077 | |
| 1078 // Shared space support | |
| 1079 void serialize_block_offset_array_offsets(SerializeOopClosure* soc); | |
| 1080 }; | |
| 1081 | |
| 1082 | |
| 1083 // Class TenuredSpace is used by TenuredGeneration | |
| 1084 | |
| 1085 class TenuredSpace: public OffsetTableContigSpace { | |
| 1086 friend class VMStructs; | |
| 1087 protected: | |
| 1088 // Mark sweep support | |
| 438 | 1089 size_t allowed_dead_ratio() const; |
| 0 | 1090 public: |
| 1091 // Constructor | |
| 1092 TenuredSpace(BlockOffsetSharedArray* sharedOffsetArray, | |
| 1093 MemRegion mr) : | |
| 1094 OffsetTableContigSpace(sharedOffsetArray, mr) {} | |
| 1095 }; | |
| 1096 | |
| 1097 | |
| 1098 // Class ContigPermSpace is used by CompactingPermGen | |
| 1099 | |
| 1100 class ContigPermSpace: public OffsetTableContigSpace { | |
| 1101 friend class VMStructs; | |
| 1102 protected: | |
| 1103 // Mark sweep support | |
| 438 | 1104 size_t allowed_dead_ratio() const; |
| 0 | 1105 public: |
| 1106 // Constructor | |
| 1107 ContigPermSpace(BlockOffsetSharedArray* sharedOffsetArray, MemRegion mr) : | |
| 1108 OffsetTableContigSpace(sharedOffsetArray, mr) {} | |
| 1109 }; |