Mercurial > hg > truffle
annotate src/share/vm/memory/cardTableModRefBS.hpp @ 845:df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
Summary: Modifications to G1 so as to allow the use of compressed oops.
Reviewed-by: apetrusenko, coleenp, jmasa, kvn, never, phh, tonyp
author | ysr |
---|---|
date | Tue, 14 Jul 2009 15:40:39 -0700 |
parents | 7bb995fbd3c0 |
children | 8624da129f0b |
rev | line source |
---|---|
0 | 1 /* |
579 | 2 * Copyright 2000-2009 Sun Microsystems, Inc. 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 * | |
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
21 * have any questions. | |
22 * | |
23 */ | |
24 | |
25 // This kind of "BarrierSet" allows a "CollectedHeap" to detect and | |
26 // enumerate ref fields that have been modified (since the last | |
27 // enumeration.) | |
28 | |
29 // As it currently stands, this barrier is *imprecise*: when a ref field in | |
30 // an object "o" is modified, the card table entry for the card containing | |
31 // the head of "o" is dirtied, not necessarily the card containing the | |
32 // modified field itself. For object arrays, however, the barrier *is* | |
33 // precise; only the card containing the modified element is dirtied. | |
34 // Any MemRegionClosures used to scan dirty cards should take these | |
35 // considerations into account. | |
36 | |
37 class Generation; | |
38 class OopsInGenClosure; | |
39 class DirtyCardToOopClosure; | |
40 | |
41 class CardTableModRefBS: public ModRefBarrierSet { | |
42 // Some classes get to look at some private stuff. | |
43 friend class BytecodeInterpreter; | |
44 friend class VMStructs; | |
45 friend class CardTableRS; | |
46 friend class CheckForUnmarkedOops; // Needs access to raw card bytes. | |
47 #ifndef PRODUCT | |
48 // For debugging. | |
49 friend class GuaranteeNotModClosure; | |
50 #endif | |
51 protected: | |
52 | |
53 enum CardValues { | |
54 clean_card = -1, | |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
55 // The mask contains zeros in places for all other values. |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
56 clean_card_mask = clean_card - 31, |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
57 |
0 | 58 dirty_card = 0, |
59 precleaned_card = 1, | |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
60 claimed_card = 2, |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
61 deferred_card = 4, |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
62 last_card = 8, |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
63 CT_MR_BS_last_reserved = 16 |
0 | 64 }; |
65 | |
66 // dirty and precleaned are equivalent wrt younger_refs_iter. | |
67 static bool card_is_dirty_wrt_gen_iter(jbyte cv) { | |
68 return cv == dirty_card || cv == precleaned_card; | |
69 } | |
70 | |
71 // Returns "true" iff the value "cv" will cause the card containing it | |
72 // to be scanned in the current traversal. May be overridden by | |
73 // subtypes. | |
74 virtual bool card_will_be_scanned(jbyte cv) { | |
75 return CardTableModRefBS::card_is_dirty_wrt_gen_iter(cv); | |
76 } | |
77 | |
78 // Returns "true" iff the value "cv" may have represented a dirty card at | |
79 // some point. | |
80 virtual bool card_may_have_been_dirty(jbyte cv) { | |
81 return card_is_dirty_wrt_gen_iter(cv); | |
82 } | |
83 | |
84 // The declaration order of these const fields is important; see the | |
85 // constructor before changing. | |
86 const MemRegion _whole_heap; // the region covered by the card table | |
87 const size_t _guard_index; // index of very last element in the card | |
88 // table; it is set to a guard value | |
89 // (last_card) and should never be modified | |
90 const size_t _last_valid_index; // index of the last valid element | |
91 const size_t _page_size; // page size used when mapping _byte_map | |
92 const size_t _byte_map_size; // in bytes | |
93 jbyte* _byte_map; // the card marking array | |
94 | |
95 int _cur_covered_regions; | |
96 // The covered regions should be in address order. | |
97 MemRegion* _covered; | |
98 // The committed regions correspond one-to-one to the covered regions. | |
99 // They represent the card-table memory that has been committed to service | |
100 // the corresponding covered region. It may be that committed region for | |
101 // one covered region corresponds to a larger region because of page-size | |
102 // roundings. Thus, a committed region for one covered region may | |
103 // actually extend onto the card-table space for the next covered region. | |
104 MemRegion* _committed; | |
105 | |
106 // The last card is a guard card, and we commit the page for it so | |
107 // we can use the card for verification purposes. We make sure we never | |
108 // uncommit the MemRegion for that page. | |
109 MemRegion _guard_region; | |
110 | |
111 protected: | |
112 // Initialization utilities; covered_words is the size of the covered region | |
113 // in, um, words. | |
114 inline size_t cards_required(size_t covered_words); | |
115 inline size_t compute_byte_map_size(); | |
116 | |
117 // Finds and return the index of the region, if any, to which the given | |
118 // region would be contiguous. If none exists, assign a new region and | |
119 // returns its index. Requires that no more than the maximum number of | |
120 // covered regions defined in the constructor are ever in use. | |
121 int find_covering_region_by_base(HeapWord* base); | |
122 | |
123 // Same as above, but finds the region containing the given address | |
124 // instead of starting at a given base address. | |
125 int find_covering_region_containing(HeapWord* addr); | |
126 | |
127 // Resize one of the regions covered by the remembered set. | |
128 void resize_covered_region(MemRegion new_region); | |
129 | |
130 // Returns the leftmost end of a committed region corresponding to a | |
131 // covered region before covered region "ind", or else "NULL" if "ind" is | |
132 // the first covered region. | |
133 HeapWord* largest_prev_committed_end(int ind) const; | |
134 | |
135 // Returns the part of the region mr that doesn't intersect with | |
136 // any committed region other than self. Used to prevent uncommitting | |
137 // regions that are also committed by other regions. Also protects | |
138 // against uncommitting the guard region. | |
139 MemRegion committed_unique_to_self(int self, MemRegion mr) const; | |
140 | |
141 // Mapping from address to card marking array entry | |
142 jbyte* byte_for(const void* p) const { | |
143 assert(_whole_heap.contains(p), | |
144 "out of bounds access to card marking array"); | |
145 jbyte* result = &byte_map_base[uintptr_t(p) >> card_shift]; | |
146 assert(result >= _byte_map && result < _byte_map + _byte_map_size, | |
147 "out of bounds accessor for card marking array"); | |
148 return result; | |
149 } | |
150 | |
151 // The card table byte one after the card marking array | |
152 // entry for argument address. Typically used for higher bounds | |
153 // for loops iterating through the card table. | |
154 jbyte* byte_after(const void* p) const { | |
155 return byte_for(p) + 1; | |
156 } | |
157 | |
158 // Iterate over the portion of the card-table which covers the given | |
159 // region mr in the given space and apply cl to any dirty sub-regions | |
160 // of mr. cl and dcto_cl must either be the same closure or cl must | |
161 // wrap dcto_cl. Both are required - neither may be NULL. Also, dcto_cl | |
162 // may be modified. Note that this function will operate in a parallel | |
163 // mode if worker threads are available. | |
164 void non_clean_card_iterate(Space* sp, MemRegion mr, | |
165 DirtyCardToOopClosure* dcto_cl, | |
166 MemRegionClosure* cl, | |
167 bool clear); | |
168 | |
169 // Utility function used to implement the other versions below. | |
170 void non_clean_card_iterate_work(MemRegion mr, MemRegionClosure* cl, | |
171 bool clear); | |
172 | |
173 void par_non_clean_card_iterate_work(Space* sp, MemRegion mr, | |
174 DirtyCardToOopClosure* dcto_cl, | |
175 MemRegionClosure* cl, | |
176 bool clear, | |
177 int n_threads); | |
178 | |
179 // Dirty the bytes corresponding to "mr" (not all of which must be | |
180 // covered.) | |
181 void dirty_MemRegion(MemRegion mr); | |
182 | |
183 // Clear (to clean_card) the bytes entirely contained within "mr" (not | |
184 // all of which must be covered.) | |
185 void clear_MemRegion(MemRegion mr); | |
186 | |
187 // *** Support for parallel card scanning. | |
188 | |
189 enum SomeConstantsForParallelism { | |
190 StridesPerThread = 2, | |
191 CardsPerStrideChunk = 256 | |
192 }; | |
193 | |
194 // This is an array, one element per covered region of the card table. | |
195 // Each entry is itself an array, with one element per chunk in the | |
196 // covered region. Each entry of these arrays is the lowest non-clean | |
197 // card of the corresponding chunk containing part of an object from the | |
198 // previous chunk, or else NULL. | |
199 typedef jbyte* CardPtr; | |
200 typedef CardPtr* CardArr; | |
201 CardArr* _lowest_non_clean; | |
202 size_t* _lowest_non_clean_chunk_size; | |
203 uintptr_t* _lowest_non_clean_base_chunk_index; | |
204 int* _last_LNC_resizing_collection; | |
205 | |
206 // Initializes "lowest_non_clean" to point to the array for the region | |
207 // covering "sp", and "lowest_non_clean_base_chunk_index" to the chunk | |
208 // index of the corresponding to the first element of that array. | |
209 // Ensures that these arrays are of sufficient size, allocating if necessary. | |
210 // May be called by several threads concurrently. | |
211 void get_LNC_array_for_space(Space* sp, | |
212 jbyte**& lowest_non_clean, | |
213 uintptr_t& lowest_non_clean_base_chunk_index, | |
214 size_t& lowest_non_clean_chunk_size); | |
215 | |
216 // Returns the number of chunks necessary to cover "mr". | |
217 size_t chunks_to_cover(MemRegion mr) { | |
218 return (size_t)(addr_to_chunk_index(mr.last()) - | |
219 addr_to_chunk_index(mr.start()) + 1); | |
220 } | |
221 | |
222 // Returns the index of the chunk in a stride which | |
223 // covers the given address. | |
224 uintptr_t addr_to_chunk_index(const void* addr) { | |
225 uintptr_t card = (uintptr_t) byte_for(addr); | |
226 return card / CardsPerStrideChunk; | |
227 } | |
228 | |
229 // Apply cl, which must either itself apply dcto_cl or be dcto_cl, | |
230 // to the cards in the stride (of n_strides) within the given space. | |
231 void process_stride(Space* sp, | |
232 MemRegion used, | |
233 jint stride, int n_strides, | |
234 DirtyCardToOopClosure* dcto_cl, | |
235 MemRegionClosure* cl, | |
236 bool clear, | |
237 jbyte** lowest_non_clean, | |
238 uintptr_t lowest_non_clean_base_chunk_index, | |
239 size_t lowest_non_clean_chunk_size); | |
240 | |
241 // Makes sure that chunk boundaries are handled appropriately, by | |
242 // adjusting the min_done of dcto_cl, and by using a special card-table | |
243 // value to indicate how min_done should be set. | |
244 void process_chunk_boundaries(Space* sp, | |
245 DirtyCardToOopClosure* dcto_cl, | |
246 MemRegion chunk_mr, | |
247 MemRegion used, | |
248 jbyte** lowest_non_clean, | |
249 uintptr_t lowest_non_clean_base_chunk_index, | |
250 size_t lowest_non_clean_chunk_size); | |
251 | |
252 public: | |
253 // Constants | |
254 enum SomePublicConstants { | |
255 card_shift = 9, | |
256 card_size = 1 << card_shift, | |
257 card_size_in_words = card_size / sizeof(HeapWord) | |
258 }; | |
259 | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
260 static int clean_card_val() { return clean_card; } |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
261 static int clean_card_mask_val() { return clean_card_mask; } |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
262 static int dirty_card_val() { return dirty_card; } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
263 static int claimed_card_val() { return claimed_card; } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
264 static int precleaned_card_val() { return precleaned_card; } |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
265 static int deferred_card_val() { return deferred_card; } |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
266 |
0 | 267 // For RTTI simulation. |
268 bool is_a(BarrierSet::Name bsn) { | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
269 return bsn == BarrierSet::CardTableModRef || ModRefBarrierSet::is_a(bsn); |
0 | 270 } |
271 | |
272 CardTableModRefBS(MemRegion whole_heap, int max_covered_regions); | |
273 | |
274 // *** Barrier set functions. | |
275 | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
276 bool has_write_ref_pre_barrier() { return false; } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
277 |
113
ba764ed4b6f2
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
0
diff
changeset
|
278 inline bool write_ref_needs_barrier(void* field, oop new_val) { |
0 | 279 // Note that this assumes the perm gen is the highest generation |
280 // in the address space | |
281 return new_val != NULL && !new_val->is_perm(); | |
282 } | |
283 | |
284 // Record a reference update. Note that these versions are precise! | |
285 // The scanning code has to handle the fact that the write barrier may be | |
286 // either precise or imprecise. We make non-virtual inline variants of | |
287 // these functions here for performance. | |
288 protected: | |
289 void write_ref_field_work(oop obj, size_t offset, oop newVal); | |
845
df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
628
diff
changeset
|
290 virtual void write_ref_field_work(void* field, oop newVal); |
0 | 291 public: |
292 | |
293 bool has_write_ref_array_opt() { return true; } | |
294 bool has_write_region_opt() { return true; } | |
295 | |
296 inline void inline_write_region(MemRegion mr) { | |
297 dirty_MemRegion(mr); | |
298 } | |
299 protected: | |
300 void write_region_work(MemRegion mr) { | |
301 inline_write_region(mr); | |
302 } | |
303 public: | |
304 | |
305 inline void inline_write_ref_array(MemRegion mr) { | |
306 dirty_MemRegion(mr); | |
307 } | |
308 protected: | |
309 void write_ref_array_work(MemRegion mr) { | |
310 inline_write_ref_array(mr); | |
311 } | |
312 public: | |
313 | |
314 bool is_aligned(HeapWord* addr) { | |
315 return is_card_aligned(addr); | |
316 } | |
317 | |
318 // *** Card-table-barrier-specific things. | |
319 | |
845
df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
628
diff
changeset
|
320 template <class T> inline void inline_write_ref_field_pre(T* field, oop newVal) {} |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
321 |
845
df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
628
diff
changeset
|
322 template <class T> inline void inline_write_ref_field(T* field, oop newVal) { |
df6caf649ff7
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
628
diff
changeset
|
323 jbyte* byte = byte_for((void*)field); |
0 | 324 *byte = dirty_card; |
325 } | |
326 | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
327 // These are used by G1, when it uses the card table as a temporary data |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
328 // structure for card claiming. |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
329 bool is_card_dirty(size_t card_index) { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
330 return _byte_map[card_index] == dirty_card_val(); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
331 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
332 |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
333 void mark_card_dirty(size_t card_index) { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
334 _byte_map[card_index] = dirty_card_val(); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
335 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
336 |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
337 bool is_card_claimed(size_t card_index) { |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
338 jbyte val = _byte_map[card_index]; |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
339 return (val & (clean_card_mask_val() | claimed_card_val())) == claimed_card_val(); |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
340 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
341 |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
342 bool claim_card(size_t card_index); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
343 |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
344 bool is_card_clean(size_t card_index) { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
345 return _byte_map[card_index] == clean_card_val(); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
346 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
347 |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
348 bool is_card_deferred(size_t card_index) { |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
349 jbyte val = _byte_map[card_index]; |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
350 return (val & (clean_card_mask_val() | deferred_card_val())) == deferred_card_val(); |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
351 } |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
352 |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
353 bool mark_card_deferred(size_t card_index); |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
354 |
0 | 355 // Card marking array base (adjusted for heap low boundary) |
356 // This would be the 0th element of _byte_map, if the heap started at 0x0. | |
357 // But since the heap starts at some higher address, this points to somewhere | |
358 // before the beginning of the actual _byte_map. | |
359 jbyte* byte_map_base; | |
360 | |
361 // Return true if "p" is at the start of a card. | |
362 bool is_card_aligned(HeapWord* p) { | |
363 jbyte* pcard = byte_for(p); | |
364 return (addr_for(pcard) == p); | |
365 } | |
366 | |
367 // The kinds of precision a CardTableModRefBS may offer. | |
368 enum PrecisionStyle { | |
369 Precise, | |
370 ObjHeadPreciseArray | |
371 }; | |
372 | |
373 // Tells what style of precision this card table offers. | |
374 PrecisionStyle precision() { | |
375 return ObjHeadPreciseArray; // Only one supported for now. | |
376 } | |
377 | |
378 // ModRefBS functions. | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
379 virtual void invalidate(MemRegion mr, bool whole_heap = false); |
0 | 380 void clear(MemRegion mr); |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
381 void dirty(MemRegion mr); |
0 | 382 void mod_oop_in_space_iterate(Space* sp, OopClosure* cl, |
383 bool clear = false, | |
384 bool before_save_marks = false); | |
385 | |
386 // *** Card-table-RemSet-specific things. | |
387 | |
388 // Invoke "cl.do_MemRegion" on a set of MemRegions that collectively | |
389 // includes all the modified cards (expressing each card as a | |
390 // MemRegion). Thus, several modified cards may be lumped into one | |
391 // region. The regions are non-overlapping, and are visited in | |
392 // *decreasing* address order. (This order aids with imprecise card | |
393 // marking, where a dirty card may cause scanning, and summarization | |
394 // marking, of objects that extend onto subsequent cards.) | |
395 // If "clear" is true, the card is (conceptually) marked unmodified before | |
396 // applying the closure. | |
397 void mod_card_iterate(MemRegionClosure* cl, bool clear = false) { | |
398 non_clean_card_iterate_work(_whole_heap, cl, clear); | |
399 } | |
400 | |
401 // Like the "mod_cards_iterate" above, except only invokes the closure | |
402 // for cards within the MemRegion "mr" (which is required to be | |
403 // card-aligned and sized.) | |
404 void mod_card_iterate(MemRegion mr, MemRegionClosure* cl, | |
405 bool clear = false) { | |
406 non_clean_card_iterate_work(mr, cl, clear); | |
407 } | |
408 | |
409 static uintx ct_max_alignment_constraint(); | |
410 | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
411 // Apply closure "cl" to the dirty cards containing some part of |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
412 // MemRegion "mr". |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
413 void dirty_card_iterate(MemRegion mr, MemRegionClosure* cl); |
0 | 414 |
415 // Return the MemRegion corresponding to the first maximal run | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
416 // of dirty cards lying completely within MemRegion mr. |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
417 // If reset is "true", then sets those card table entries to the given |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
418 // value. |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
419 MemRegion dirty_card_range_after_reset(MemRegion mr, bool reset, |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
420 int reset_val); |
0 | 421 |
422 // Set all the dirty cards in the given region to precleaned state. | |
423 void preclean_dirty_cards(MemRegion mr); | |
424 | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
425 // Provide read-only access to the card table array. |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
426 const jbyte* byte_for_const(const void* p) const { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
427 return byte_for(p); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
428 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
429 const jbyte* byte_after_const(const void* p) const { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
430 return byte_after(p); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
431 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
432 |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
433 // Mapping from card marking array entry to address of first word |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
434 HeapWord* addr_for(const jbyte* p) const { |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
435 assert(p >= _byte_map && p < _byte_map + _byte_map_size, |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
436 "out of bounds access to card marking array"); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
437 size_t delta = pointer_delta(p, byte_map_base, sizeof(jbyte)); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
438 HeapWord* result = (HeapWord*) (delta << card_shift); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
439 assert(_whole_heap.contains(result), |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
440 "out of bounds accessor from card marking array"); |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
441 return result; |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
442 } |
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
443 |
0 | 444 // Mapping from address to card marking array index. |
489
2494ab195856
6653214: MemoryPoolMXBean.setUsageThreshold() does not support large heap sizes.
swamyv
parents:
356
diff
changeset
|
445 size_t index_for(void* p) { |
0 | 446 assert(_whole_heap.contains(p), |
447 "out of bounds access to card marking array"); | |
448 return byte_for(p) - _byte_map; | |
449 } | |
450 | |
616
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
451 const jbyte* byte_for_index(const size_t card_index) const { |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
452 return _byte_map + card_index; |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
453 } |
4f360ec815ba
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
489
diff
changeset
|
454 |
0 | 455 void verify(); |
456 void verify_guard(); | |
457 | |
458 void verify_clean_region(MemRegion mr) PRODUCT_RETURN; | |
459 | |
460 static size_t par_chunk_heapword_alignment() { | |
461 return CardsPerStrideChunk * card_size_in_words; | |
462 } | |
342
37f87013dfd8
6711316: Open source the Garbage-First garbage collector
ysr
parents:
113
diff
changeset
|
463 |
0 | 464 }; |
465 | |
466 class CardTableRS; | |
467 | |
468 // A specialization for the CardTableRS gen rem set. | |
469 class CardTableModRefBSForCTRS: public CardTableModRefBS { | |
470 CardTableRS* _rs; | |
471 protected: | |
472 bool card_will_be_scanned(jbyte cv); | |
473 bool card_may_have_been_dirty(jbyte cv); | |
474 public: | |
475 CardTableModRefBSForCTRS(MemRegion whole_heap, | |
476 int max_covered_regions) : | |
477 CardTableModRefBS(whole_heap, max_covered_regions) {} | |
478 | |
479 void set_CTRS(CardTableRS* rs) { _rs = rs; } | |
480 }; |