author | tonyp |
Wed, 30 Mar 2011 10:26:59 -0400 | |
changeset 8928 | e5c53268bef5 |
parent 7397 | 5b173b4ca846 |
child 9183 | 3d0e0687fe28 |
permissions | -rw-r--r-- |
1 | 1 |
/* |
6187 | 2 |
* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. |
1 | 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 |
* |
|
5547
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
4902
diff
changeset
|
19 |
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
4902
diff
changeset
|
20 |
* or visit www.oracle.com if you need additional information or have any |
f4b087cbb361
6941466: Oracle rebranding changes for Hotspot repositories
trims
parents:
4902
diff
changeset
|
21 |
* questions. |
1 | 22 |
* |
23 |
*/ |
|
24 |
||
7397 | 25 |
#ifndef SHARE_VM_MEMORY_CARDTABLEMODREFBS_HPP |
26 |
#define SHARE_VM_MEMORY_CARDTABLEMODREFBS_HPP |
|
27 |
||
28 |
#include "memory/modRefBarrierSet.hpp" |
|
29 |
#include "oops/oop.hpp" |
|
30 |
#include "oops/oop.inline2.hpp" |
|
31 |
||
1 | 32 |
// This kind of "BarrierSet" allows a "CollectedHeap" to detect and |
33 |
// enumerate ref fields that have been modified (since the last |
|
34 |
// enumeration.) |
|
35 |
||
36 |
// As it currently stands, this barrier is *imprecise*: when a ref field in |
|
37 |
// an object "o" is modified, the card table entry for the card containing |
|
38 |
// the head of "o" is dirtied, not necessarily the card containing the |
|
39 |
// modified field itself. For object arrays, however, the barrier *is* |
|
40 |
// precise; only the card containing the modified element is dirtied. |
|
41 |
// Any MemRegionClosures used to scan dirty cards should take these |
|
42 |
// considerations into account. |
|
43 |
||
44 |
class Generation; |
|
45 |
class OopsInGenClosure; |
|
46 |
class DirtyCardToOopClosure; |
|
47 |
||
48 |
class CardTableModRefBS: public ModRefBarrierSet { |
|
49 |
// Some classes get to look at some private stuff. |
|
50 |
friend class BytecodeInterpreter; |
|
51 |
friend class VMStructs; |
|
52 |
friend class CardTableRS; |
|
53 |
friend class CheckForUnmarkedOops; // Needs access to raw card bytes. |
|
6187 | 54 |
friend class SharkBuilder; |
1 | 55 |
#ifndef PRODUCT |
56 |
// For debugging. |
|
57 |
friend class GuaranteeNotModClosure; |
|
58 |
#endif |
|
59 |
protected: |
|
60 |
||
61 |
enum CardValues { |
|
62 |
clean_card = -1, |
|
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
63 |
// The mask contains zeros in places for all other values. |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
64 |
clean_card_mask = clean_card - 31, |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
65 |
|
1 | 66 |
dirty_card = 0, |
67 |
precleaned_card = 1, |
|
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
68 |
claimed_card = 2, |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
69 |
deferred_card = 4, |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
70 |
last_card = 8, |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
71 |
CT_MR_BS_last_reserved = 16 |
1 | 72 |
}; |
73 |
||
74 |
// dirty and precleaned are equivalent wrt younger_refs_iter. |
|
75 |
static bool card_is_dirty_wrt_gen_iter(jbyte cv) { |
|
76 |
return cv == dirty_card || cv == precleaned_card; |
|
77 |
} |
|
78 |
||
79 |
// Returns "true" iff the value "cv" will cause the card containing it |
|
80 |
// to be scanned in the current traversal. May be overridden by |
|
81 |
// subtypes. |
|
82 |
virtual bool card_will_be_scanned(jbyte cv) { |
|
83 |
return CardTableModRefBS::card_is_dirty_wrt_gen_iter(cv); |
|
84 |
} |
|
85 |
||
86 |
// Returns "true" iff the value "cv" may have represented a dirty card at |
|
87 |
// some point. |
|
88 |
virtual bool card_may_have_been_dirty(jbyte cv) { |
|
89 |
return card_is_dirty_wrt_gen_iter(cv); |
|
90 |
} |
|
91 |
||
92 |
// The declaration order of these const fields is important; see the |
|
93 |
// constructor before changing. |
|
94 |
const MemRegion _whole_heap; // the region covered by the card table |
|
95 |
const size_t _guard_index; // index of very last element in the card |
|
96 |
// table; it is set to a guard value |
|
97 |
// (last_card) and should never be modified |
|
98 |
const size_t _last_valid_index; // index of the last valid element |
|
99 |
const size_t _page_size; // page size used when mapping _byte_map |
|
100 |
const size_t _byte_map_size; // in bytes |
|
101 |
jbyte* _byte_map; // the card marking array |
|
102 |
||
103 |
int _cur_covered_regions; |
|
104 |
// The covered regions should be in address order. |
|
105 |
MemRegion* _covered; |
|
106 |
// The committed regions correspond one-to-one to the covered regions. |
|
107 |
// They represent the card-table memory that has been committed to service |
|
108 |
// the corresponding covered region. It may be that committed region for |
|
109 |
// one covered region corresponds to a larger region because of page-size |
|
110 |
// roundings. Thus, a committed region for one covered region may |
|
111 |
// actually extend onto the card-table space for the next covered region. |
|
112 |
MemRegion* _committed; |
|
113 |
||
114 |
// The last card is a guard card, and we commit the page for it so |
|
115 |
// we can use the card for verification purposes. We make sure we never |
|
116 |
// uncommit the MemRegion for that page. |
|
117 |
MemRegion _guard_region; |
|
118 |
||
119 |
protected: |
|
120 |
// Initialization utilities; covered_words is the size of the covered region |
|
121 |
// in, um, words. |
|
122 |
inline size_t cards_required(size_t covered_words); |
|
123 |
inline size_t compute_byte_map_size(); |
|
124 |
||
125 |
// Finds and return the index of the region, if any, to which the given |
|
126 |
// region would be contiguous. If none exists, assign a new region and |
|
127 |
// returns its index. Requires that no more than the maximum number of |
|
128 |
// covered regions defined in the constructor are ever in use. |
|
129 |
int find_covering_region_by_base(HeapWord* base); |
|
130 |
||
131 |
// Same as above, but finds the region containing the given address |
|
132 |
// instead of starting at a given base address. |
|
133 |
int find_covering_region_containing(HeapWord* addr); |
|
134 |
||
135 |
// Resize one of the regions covered by the remembered set. |
|
136 |
void resize_covered_region(MemRegion new_region); |
|
137 |
||
138 |
// Returns the leftmost end of a committed region corresponding to a |
|
139 |
// covered region before covered region "ind", or else "NULL" if "ind" is |
|
140 |
// the first covered region. |
|
141 |
HeapWord* largest_prev_committed_end(int ind) const; |
|
142 |
||
143 |
// Returns the part of the region mr that doesn't intersect with |
|
144 |
// any committed region other than self. Used to prevent uncommitting |
|
145 |
// regions that are also committed by other regions. Also protects |
|
146 |
// against uncommitting the guard region. |
|
147 |
MemRegion committed_unique_to_self(int self, MemRegion mr) const; |
|
148 |
||
149 |
// Mapping from address to card marking array entry |
|
150 |
jbyte* byte_for(const void* p) const { |
|
151 |
assert(_whole_heap.contains(p), |
|
152 |
"out of bounds access to card marking array"); |
|
153 |
jbyte* result = &byte_map_base[uintptr_t(p) >> card_shift]; |
|
154 |
assert(result >= _byte_map && result < _byte_map + _byte_map_size, |
|
155 |
"out of bounds accessor for card marking array"); |
|
156 |
return result; |
|
157 |
} |
|
158 |
||
159 |
// The card table byte one after the card marking array |
|
160 |
// entry for argument address. Typically used for higher bounds |
|
161 |
// for loops iterating through the card table. |
|
162 |
jbyte* byte_after(const void* p) const { |
|
163 |
return byte_for(p) + 1; |
|
164 |
} |
|
165 |
||
166 |
// Iterate over the portion of the card-table which covers the given |
|
167 |
// region mr in the given space and apply cl to any dirty sub-regions |
|
168 |
// of mr. cl and dcto_cl must either be the same closure or cl must |
|
169 |
// wrap dcto_cl. Both are required - neither may be NULL. Also, dcto_cl |
|
170 |
// may be modified. Note that this function will operate in a parallel |
|
171 |
// mode if worker threads are available. |
|
172 |
void non_clean_card_iterate(Space* sp, MemRegion mr, |
|
173 |
DirtyCardToOopClosure* dcto_cl, |
|
174 |
MemRegionClosure* cl, |
|
175 |
bool clear); |
|
176 |
||
177 |
// Utility function used to implement the other versions below. |
|
178 |
void non_clean_card_iterate_work(MemRegion mr, MemRegionClosure* cl, |
|
179 |
bool clear); |
|
180 |
||
181 |
void par_non_clean_card_iterate_work(Space* sp, MemRegion mr, |
|
182 |
DirtyCardToOopClosure* dcto_cl, |
|
183 |
MemRegionClosure* cl, |
|
184 |
bool clear, |
|
185 |
int n_threads); |
|
186 |
||
187 |
// Dirty the bytes corresponding to "mr" (not all of which must be |
|
188 |
// covered.) |
|
189 |
void dirty_MemRegion(MemRegion mr); |
|
190 |
||
191 |
// Clear (to clean_card) the bytes entirely contained within "mr" (not |
|
192 |
// all of which must be covered.) |
|
193 |
void clear_MemRegion(MemRegion mr); |
|
194 |
||
195 |
// *** Support for parallel card scanning. |
|
196 |
||
197 |
enum SomeConstantsForParallelism { |
|
198 |
StridesPerThread = 2, |
|
199 |
CardsPerStrideChunk = 256 |
|
200 |
}; |
|
201 |
||
202 |
// This is an array, one element per covered region of the card table. |
|
203 |
// Each entry is itself an array, with one element per chunk in the |
|
204 |
// covered region. Each entry of these arrays is the lowest non-clean |
|
205 |
// card of the corresponding chunk containing part of an object from the |
|
206 |
// previous chunk, or else NULL. |
|
207 |
typedef jbyte* CardPtr; |
|
208 |
typedef CardPtr* CardArr; |
|
209 |
CardArr* _lowest_non_clean; |
|
210 |
size_t* _lowest_non_clean_chunk_size; |
|
211 |
uintptr_t* _lowest_non_clean_base_chunk_index; |
|
212 |
int* _last_LNC_resizing_collection; |
|
213 |
||
214 |
// Initializes "lowest_non_clean" to point to the array for the region |
|
215 |
// covering "sp", and "lowest_non_clean_base_chunk_index" to the chunk |
|
216 |
// index of the corresponding to the first element of that array. |
|
217 |
// Ensures that these arrays are of sufficient size, allocating if necessary. |
|
218 |
// May be called by several threads concurrently. |
|
219 |
void get_LNC_array_for_space(Space* sp, |
|
220 |
jbyte**& lowest_non_clean, |
|
221 |
uintptr_t& lowest_non_clean_base_chunk_index, |
|
222 |
size_t& lowest_non_clean_chunk_size); |
|
223 |
||
224 |
// Returns the number of chunks necessary to cover "mr". |
|
225 |
size_t chunks_to_cover(MemRegion mr) { |
|
226 |
return (size_t)(addr_to_chunk_index(mr.last()) - |
|
227 |
addr_to_chunk_index(mr.start()) + 1); |
|
228 |
} |
|
229 |
||
230 |
// Returns the index of the chunk in a stride which |
|
231 |
// covers the given address. |
|
232 |
uintptr_t addr_to_chunk_index(const void* addr) { |
|
233 |
uintptr_t card = (uintptr_t) byte_for(addr); |
|
234 |
return card / CardsPerStrideChunk; |
|
235 |
} |
|
236 |
||
237 |
// Apply cl, which must either itself apply dcto_cl or be dcto_cl, |
|
238 |
// to the cards in the stride (of n_strides) within the given space. |
|
239 |
void process_stride(Space* sp, |
|
240 |
MemRegion used, |
|
241 |
jint stride, int n_strides, |
|
242 |
DirtyCardToOopClosure* dcto_cl, |
|
243 |
MemRegionClosure* cl, |
|
244 |
bool clear, |
|
245 |
jbyte** lowest_non_clean, |
|
246 |
uintptr_t lowest_non_clean_base_chunk_index, |
|
247 |
size_t lowest_non_clean_chunk_size); |
|
248 |
||
249 |
// Makes sure that chunk boundaries are handled appropriately, by |
|
250 |
// adjusting the min_done of dcto_cl, and by using a special card-table |
|
251 |
// value to indicate how min_done should be set. |
|
252 |
void process_chunk_boundaries(Space* sp, |
|
253 |
DirtyCardToOopClosure* dcto_cl, |
|
254 |
MemRegion chunk_mr, |
|
255 |
MemRegion used, |
|
256 |
jbyte** lowest_non_clean, |
|
257 |
uintptr_t lowest_non_clean_base_chunk_index, |
|
258 |
size_t lowest_non_clean_chunk_size); |
|
259 |
||
260 |
public: |
|
261 |
// Constants |
|
262 |
enum SomePublicConstants { |
|
263 |
card_shift = 9, |
|
264 |
card_size = 1 << card_shift, |
|
265 |
card_size_in_words = card_size / sizeof(HeapWord) |
|
266 |
}; |
|
267 |
||
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
268 |
static int clean_card_val() { return clean_card; } |
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
269 |
static int clean_card_mask_val() { return clean_card_mask; } |
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
270 |
static int dirty_card_val() { return dirty_card; } |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
271 |
static int claimed_card_val() { return claimed_card; } |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
272 |
static int precleaned_card_val() { return precleaned_card; } |
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
273 |
static int deferred_card_val() { return deferred_card; } |
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
274 |
|
1 | 275 |
// For RTTI simulation. |
276 |
bool is_a(BarrierSet::Name bsn) { |
|
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
277 |
return bsn == BarrierSet::CardTableModRef || ModRefBarrierSet::is_a(bsn); |
1 | 278 |
} |
279 |
||
280 |
CardTableModRefBS(MemRegion whole_heap, int max_covered_regions); |
|
281 |
||
282 |
// *** Barrier set functions. |
|
283 |
||
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
284 |
bool has_write_ref_pre_barrier() { return false; } |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
285 |
|
360
21d113ecbf6a
6420645: Create a vm that uses compressed oops for up to 32gb heapsizes
coleenp
parents:
1
diff
changeset
|
286 |
inline bool write_ref_needs_barrier(void* field, oop new_val) { |
1 | 287 |
// Note that this assumes the perm gen is the highest generation |
288 |
// in the address space |
|
289 |
return new_val != NULL && !new_val->is_perm(); |
|
290 |
} |
|
291 |
||
292 |
// Record a reference update. Note that these versions are precise! |
|
293 |
// The scanning code has to handle the fact that the write barrier may be |
|
294 |
// either precise or imprecise. We make non-virtual inline variants of |
|
295 |
// these functions here for performance. |
|
296 |
protected: |
|
297 |
void write_ref_field_work(oop obj, size_t offset, oop newVal); |
|
3262
30d1c247fc25
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
2154
diff
changeset
|
298 |
virtual void write_ref_field_work(void* field, oop newVal); |
1 | 299 |
public: |
300 |
||
301 |
bool has_write_ref_array_opt() { return true; } |
|
302 |
bool has_write_region_opt() { return true; } |
|
303 |
||
304 |
inline void inline_write_region(MemRegion mr) { |
|
305 |
dirty_MemRegion(mr); |
|
306 |
} |
|
307 |
protected: |
|
308 |
void write_region_work(MemRegion mr) { |
|
309 |
inline_write_region(mr); |
|
310 |
} |
|
311 |
public: |
|
312 |
||
313 |
inline void inline_write_ref_array(MemRegion mr) { |
|
314 |
dirty_MemRegion(mr); |
|
315 |
} |
|
316 |
protected: |
|
317 |
void write_ref_array_work(MemRegion mr) { |
|
318 |
inline_write_ref_array(mr); |
|
319 |
} |
|
320 |
public: |
|
321 |
||
322 |
bool is_aligned(HeapWord* addr) { |
|
323 |
return is_card_aligned(addr); |
|
324 |
} |
|
325 |
||
326 |
// *** Card-table-barrier-specific things. |
|
327 |
||
3262
30d1c247fc25
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
2154
diff
changeset
|
328 |
template <class T> inline void inline_write_ref_field_pre(T* field, oop newVal) {} |
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
329 |
|
3262
30d1c247fc25
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
2154
diff
changeset
|
330 |
template <class T> inline void inline_write_ref_field(T* field, oop newVal) { |
30d1c247fc25
6700789: G1: Enable use of compressed oops with G1 heaps
ysr
parents:
2154
diff
changeset
|
331 |
jbyte* byte = byte_for((void*)field); |
1 | 332 |
*byte = dirty_card; |
333 |
} |
|
334 |
||
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
335 |
// These are used by G1, when it uses the card table as a temporary data |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
336 |
// structure for card claiming. |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
337 |
bool is_card_dirty(size_t card_index) { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
338 |
return _byte_map[card_index] == dirty_card_val(); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
339 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
340 |
|
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
341 |
void mark_card_dirty(size_t card_index) { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
342 |
_byte_map[card_index] = dirty_card_val(); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
343 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
344 |
|
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
345 |
bool is_card_claimed(size_t card_index) { |
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
346 |
jbyte val = _byte_map[card_index]; |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
347 |
return (val & (clean_card_mask_val() | claimed_card_val())) == claimed_card_val(); |
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
348 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
349 |
|
4902
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
350 |
void set_card_claimed(size_t card_index) { |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
351 |
jbyte val = _byte_map[card_index]; |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
352 |
if (val == clean_card_val()) { |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
353 |
val = (jbyte)claimed_card_val(); |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
354 |
} else { |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
355 |
val |= (jbyte)claimed_card_val(); |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
356 |
} |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
357 |
_byte_map[card_index] = val; |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
358 |
} |
991aaddb5165
6923991: G1: improve scalability of RSet scanning
iveresov
parents:
3695
diff
changeset
|
359 |
|
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
360 |
bool claim_card(size_t card_index); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
361 |
|
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
362 |
bool is_card_clean(size_t card_index) { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
363 |
return _byte_map[card_index] == clean_card_val(); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
364 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
365 |
|
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
366 |
bool is_card_deferred(size_t card_index) { |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
367 |
jbyte val = _byte_map[card_index]; |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
368 |
return (val & (clean_card_mask_val() | deferred_card_val())) == deferred_card_val(); |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
369 |
} |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
370 |
|
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
371 |
bool mark_card_deferred(size_t card_index); |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
372 |
|
1 | 373 |
// Card marking array base (adjusted for heap low boundary) |
374 |
// This would be the 0th element of _byte_map, if the heap started at 0x0. |
|
375 |
// But since the heap starts at some higher address, this points to somewhere |
|
376 |
// before the beginning of the actual _byte_map. |
|
377 |
jbyte* byte_map_base; |
|
378 |
||
379 |
// Return true if "p" is at the start of a card. |
|
380 |
bool is_card_aligned(HeapWord* p) { |
|
381 |
jbyte* pcard = byte_for(p); |
|
382 |
return (addr_for(pcard) == p); |
|
383 |
} |
|
384 |
||
8928
e5c53268bef5
7023069: G1: Introduce symmetric locking in the slow allocation path
tonyp
parents:
7397
diff
changeset
|
385 |
HeapWord* align_to_card_boundary(HeapWord* p) { |
e5c53268bef5
7023069: G1: Introduce symmetric locking in the slow allocation path
tonyp
parents:
7397
diff
changeset
|
386 |
jbyte* pcard = byte_for(p + card_size_in_words - 1); |
e5c53268bef5
7023069: G1: Introduce symmetric locking in the slow allocation path
tonyp
parents:
7397
diff
changeset
|
387 |
return addr_for(pcard); |
e5c53268bef5
7023069: G1: Introduce symmetric locking in the slow allocation path
tonyp
parents:
7397
diff
changeset
|
388 |
} |
e5c53268bef5
7023069: G1: Introduce symmetric locking in the slow allocation path
tonyp
parents:
7397
diff
changeset
|
389 |
|
1 | 390 |
// The kinds of precision a CardTableModRefBS may offer. |
391 |
enum PrecisionStyle { |
|
392 |
Precise, |
|
393 |
ObjHeadPreciseArray |
|
394 |
}; |
|
395 |
||
396 |
// Tells what style of precision this card table offers. |
|
397 |
PrecisionStyle precision() { |
|
398 |
return ObjHeadPreciseArray; // Only one supported for now. |
|
399 |
} |
|
400 |
||
401 |
// ModRefBS functions. |
|
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
402 |
virtual void invalidate(MemRegion mr, bool whole_heap = false); |
1 | 403 |
void clear(MemRegion mr); |
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
404 |
void dirty(MemRegion mr); |
1 | 405 |
void mod_oop_in_space_iterate(Space* sp, OopClosure* cl, |
406 |
bool clear = false, |
|
407 |
bool before_save_marks = false); |
|
408 |
||
409 |
// *** Card-table-RemSet-specific things. |
|
410 |
||
411 |
// Invoke "cl.do_MemRegion" on a set of MemRegions that collectively |
|
412 |
// includes all the modified cards (expressing each card as a |
|
413 |
// MemRegion). Thus, several modified cards may be lumped into one |
|
414 |
// region. The regions are non-overlapping, and are visited in |
|
415 |
// *decreasing* address order. (This order aids with imprecise card |
|
416 |
// marking, where a dirty card may cause scanning, and summarization |
|
417 |
// marking, of objects that extend onto subsequent cards.) |
|
418 |
// If "clear" is true, the card is (conceptually) marked unmodified before |
|
419 |
// applying the closure. |
|
420 |
void mod_card_iterate(MemRegionClosure* cl, bool clear = false) { |
|
421 |
non_clean_card_iterate_work(_whole_heap, cl, clear); |
|
422 |
} |
|
423 |
||
424 |
// Like the "mod_cards_iterate" above, except only invokes the closure |
|
425 |
// for cards within the MemRegion "mr" (which is required to be |
|
426 |
// card-aligned and sized.) |
|
427 |
void mod_card_iterate(MemRegion mr, MemRegionClosure* cl, |
|
428 |
bool clear = false) { |
|
429 |
non_clean_card_iterate_work(mr, cl, clear); |
|
430 |
} |
|
431 |
||
432 |
static uintx ct_max_alignment_constraint(); |
|
433 |
||
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
434 |
// Apply closure "cl" to the dirty cards containing some part of |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
435 |
// MemRegion "mr". |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
436 |
void dirty_card_iterate(MemRegion mr, MemRegionClosure* cl); |
1 | 437 |
|
438 |
// Return the MemRegion corresponding to the first maximal run |
|
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
439 |
// of dirty cards lying completely within MemRegion mr. |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
440 |
// If reset is "true", then sets those card table entries to the given |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
441 |
// value. |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
442 |
MemRegion dirty_card_range_after_reset(MemRegion mr, bool reset, |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
443 |
int reset_val); |
1 | 444 |
|
445 |
// Set all the dirty cards in the given region to precleaned state. |
|
446 |
void preclean_dirty_cards(MemRegion mr); |
|
447 |
||
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
448 |
// Provide read-only access to the card table array. |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
449 |
const jbyte* byte_for_const(const void* p) const { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
450 |
return byte_for(p); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
451 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
452 |
const jbyte* byte_after_const(const void* p) const { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
453 |
return byte_after(p); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
454 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
455 |
|
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
456 |
// Mapping from card marking array entry to address of first word |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
457 |
HeapWord* addr_for(const jbyte* p) const { |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
458 |
assert(p >= _byte_map && p < _byte_map + _byte_map_size, |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
459 |
"out of bounds access to card marking array"); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
460 |
size_t delta = pointer_delta(p, byte_map_base, sizeof(jbyte)); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
461 |
HeapWord* result = (HeapWord*) (delta << card_shift); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
462 |
assert(_whole_heap.contains(result), |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
463 |
"out of bounds accessor from card marking array"); |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
464 |
return result; |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
465 |
} |
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
466 |
|
1 | 467 |
// Mapping from address to card marking array index. |
1676
d80e69372634
6653214: MemoryPoolMXBean.setUsageThreshold() does not support large heap sizes.
swamyv
parents:
1388
diff
changeset
|
468 |
size_t index_for(void* p) { |
1 | 469 |
assert(_whole_heap.contains(p), |
470 |
"out of bounds access to card marking array"); |
|
471 |
return byte_for(p) - _byte_map; |
|
472 |
} |
|
473 |
||
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
474 |
const jbyte* byte_for_index(const size_t card_index) const { |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
475 |
return _byte_map + card_index; |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
476 |
} |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
1676
diff
changeset
|
477 |
|
1 | 478 |
void verify(); |
479 |
void verify_guard(); |
|
480 |
||
481 |
void verify_clean_region(MemRegion mr) PRODUCT_RETURN; |
|
3695
421cfcc8843c
6841313: G1: dirty cards of survivor regions in parallel
apetrusenko
parents:
3262
diff
changeset
|
482 |
void verify_dirty_region(MemRegion mr) PRODUCT_RETURN; |
1 | 483 |
|
484 |
static size_t par_chunk_heapword_alignment() { |
|
485 |
return CardsPerStrideChunk * card_size_in_words; |
|
486 |
} |
|
1374
4c24294029a9
6711316: Open source the Garbage-First garbage collector
ysr
parents:
360
diff
changeset
|
487 |
|
1 | 488 |
}; |
489 |
||
490 |
class CardTableRS; |
|
491 |
||
492 |
// A specialization for the CardTableRS gen rem set. |
|
493 |
class CardTableModRefBSForCTRS: public CardTableModRefBS { |
|
494 |
CardTableRS* _rs; |
|
495 |
protected: |
|
496 |
bool card_will_be_scanned(jbyte cv); |
|
497 |
bool card_may_have_been_dirty(jbyte cv); |
|
498 |
public: |
|
499 |
CardTableModRefBSForCTRS(MemRegion whole_heap, |
|
500 |
int max_covered_regions) : |
|
501 |
CardTableModRefBS(whole_heap, max_covered_regions) {} |
|
502 |
||
503 |
void set_CTRS(CardTableRS* rs) { _rs = rs; } |
|
504 |
}; |
|
7397 | 505 |
|
506 |
#endif // SHARE_VM_MEMORY_CARDTABLEMODREFBS_HPP |