author | apetrusenko |
Wed, 25 Mar 2009 13:10:54 -0700 | |
changeset 2344 | f2e09ba7ceab |
parent 2252 | 703d28e44a42 |
child 2345 | 3098a48a7240 |
permissions | -rw-r--r-- |
1374 | 1 |
/* |
2105 | 2 |
* Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. |
1374 | 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 |
// A "G1CollectedHeap" is an implementation of a java heap for HotSpot. |
|
26 |
// It uses the "Garbage First" heap organization and algorithm, which |
|
27 |
// may combine concurrent marking with parallel, incremental compaction of |
|
28 |
// heap subsets that will yield large amounts of garbage. |
|
29 |
||
30 |
class HeapRegion; |
|
31 |
class HeapRegionSeq; |
|
32 |
class PermanentGenerationSpec; |
|
33 |
class GenerationSpec; |
|
34 |
class OopsInHeapRegionClosure; |
|
35 |
class G1ScanHeapEvacClosure; |
|
36 |
class ObjectClosure; |
|
37 |
class SpaceClosure; |
|
38 |
class CompactibleSpaceClosure; |
|
39 |
class Space; |
|
40 |
class G1CollectorPolicy; |
|
41 |
class GenRemSet; |
|
42 |
class G1RemSet; |
|
43 |
class HeapRegionRemSetIterator; |
|
44 |
class ConcurrentMark; |
|
45 |
class ConcurrentMarkThread; |
|
46 |
class ConcurrentG1Refine; |
|
47 |
class ConcurrentZFThread; |
|
48 |
||
49 |
// If want to accumulate detailed statistics on work queues |
|
50 |
// turn this on. |
|
51 |
#define G1_DETAILED_STATS 0 |
|
52 |
||
53 |
#if G1_DETAILED_STATS |
|
54 |
# define IF_G1_DETAILED_STATS(code) code |
|
55 |
#else |
|
56 |
# define IF_G1_DETAILED_STATS(code) |
|
57 |
#endif |
|
58 |
||
59 |
typedef GenericTaskQueue<oop*> RefToScanQueue; |
|
60 |
typedef GenericTaskQueueSet<oop*> RefToScanQueueSet; |
|
61 |
||
62 |
enum G1GCThreadGroups { |
|
63 |
G1CRGroup = 0, |
|
64 |
G1ZFGroup = 1, |
|
65 |
G1CMGroup = 2, |
|
66 |
G1CLGroup = 3 |
|
67 |
}; |
|
68 |
||
69 |
enum GCAllocPurpose { |
|
70 |
GCAllocForTenured, |
|
71 |
GCAllocForSurvived, |
|
72 |
GCAllocPurposeCount |
|
73 |
}; |
|
74 |
||
75 |
class YoungList : public CHeapObj { |
|
76 |
private: |
|
77 |
G1CollectedHeap* _g1h; |
|
78 |
||
79 |
HeapRegion* _head; |
|
80 |
||
81 |
HeapRegion* _scan_only_head; |
|
82 |
HeapRegion* _scan_only_tail; |
|
83 |
size_t _length; |
|
84 |
size_t _scan_only_length; |
|
85 |
||
86 |
size_t _last_sampled_rs_lengths; |
|
87 |
size_t _sampled_rs_lengths; |
|
88 |
HeapRegion* _curr; |
|
89 |
HeapRegion* _curr_scan_only; |
|
90 |
||
91 |
HeapRegion* _survivor_head; |
|
2009 | 92 |
HeapRegion* _survivor_tail; |
1374 | 93 |
size_t _survivor_length; |
94 |
||
95 |
void empty_list(HeapRegion* list); |
|
96 |
||
97 |
public: |
|
98 |
YoungList(G1CollectedHeap* g1h); |
|
99 |
||
100 |
void push_region(HeapRegion* hr); |
|
101 |
void add_survivor_region(HeapRegion* hr); |
|
102 |
HeapRegion* pop_region(); |
|
103 |
void empty_list(); |
|
104 |
bool is_empty() { return _length == 0; } |
|
105 |
size_t length() { return _length; } |
|
106 |
size_t scan_only_length() { return _scan_only_length; } |
|
2009 | 107 |
size_t survivor_length() { return _survivor_length; } |
1374 | 108 |
|
109 |
void rs_length_sampling_init(); |
|
110 |
bool rs_length_sampling_more(); |
|
111 |
void rs_length_sampling_next(); |
|
112 |
||
113 |
void reset_sampled_info() { |
|
114 |
_last_sampled_rs_lengths = 0; |
|
115 |
} |
|
116 |
size_t sampled_rs_lengths() { return _last_sampled_rs_lengths; } |
|
117 |
||
118 |
// for development purposes |
|
119 |
void reset_auxilary_lists(); |
|
120 |
HeapRegion* first_region() { return _head; } |
|
121 |
HeapRegion* first_scan_only_region() { return _scan_only_head; } |
|
122 |
HeapRegion* first_survivor_region() { return _survivor_head; } |
|
2009 | 123 |
HeapRegion* last_survivor_region() { return _survivor_tail; } |
1374 | 124 |
HeapRegion* par_get_next_scan_only_region() { |
125 |
MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag); |
|
126 |
HeapRegion* ret = _curr_scan_only; |
|
127 |
if (ret != NULL) |
|
128 |
_curr_scan_only = ret->get_next_young_region(); |
|
129 |
return ret; |
|
130 |
} |
|
131 |
||
132 |
// debugging |
|
133 |
bool check_list_well_formed(); |
|
134 |
bool check_list_empty(bool ignore_scan_only_list, |
|
135 |
bool check_sample = true); |
|
136 |
void print(); |
|
137 |
}; |
|
138 |
||
139 |
class RefineCardTableEntryClosure; |
|
140 |
class G1CollectedHeap : public SharedHeap { |
|
141 |
friend class VM_G1CollectForAllocation; |
|
142 |
friend class VM_GenCollectForPermanentAllocation; |
|
143 |
friend class VM_G1CollectFull; |
|
144 |
friend class VM_G1IncCollectionPause; |
|
145 |
friend class VMStructs; |
|
146 |
||
147 |
// Closures used in implementation. |
|
148 |
friend class G1ParCopyHelper; |
|
149 |
friend class G1IsAliveClosure; |
|
150 |
friend class G1EvacuateFollowersClosure; |
|
151 |
friend class G1ParScanThreadState; |
|
152 |
friend class G1ParScanClosureSuper; |
|
153 |
friend class G1ParEvacuateFollowersClosure; |
|
154 |
friend class G1ParTask; |
|
155 |
friend class G1FreeGarbageRegionClosure; |
|
156 |
friend class RefineCardTableEntryClosure; |
|
157 |
friend class G1PrepareCompactClosure; |
|
158 |
friend class RegionSorter; |
|
159 |
friend class CountRCClosure; |
|
160 |
friend class EvacPopObjClosure; |
|
161 |
||
162 |
// Other related classes. |
|
163 |
friend class G1MarkSweep; |
|
164 |
||
165 |
private: |
|
166 |
enum SomePrivateConstants { |
|
167 |
VeryLargeInBytes = HeapRegion::GrainBytes/2, |
|
168 |
VeryLargeInWords = VeryLargeInBytes/HeapWordSize, |
|
169 |
MinHeapDeltaBytes = 10 * HeapRegion::GrainBytes, // FIXME |
|
170 |
NumAPIs = HeapRegion::MaxAge |
|
171 |
}; |
|
172 |
||
173 |
// The one and only G1CollectedHeap, so static functions can find it. |
|
174 |
static G1CollectedHeap* _g1h; |
|
175 |
||
176 |
// Storage for the G1 heap (excludes the permanent generation). |
|
177 |
VirtualSpace _g1_storage; |
|
178 |
MemRegion _g1_reserved; |
|
179 |
||
180 |
// The part of _g1_storage that is currently committed. |
|
181 |
MemRegion _g1_committed; |
|
182 |
||
183 |
// The maximum part of _g1_storage that has ever been committed. |
|
184 |
MemRegion _g1_max_committed; |
|
185 |
||
186 |
// The number of regions that are completely free. |
|
187 |
size_t _free_regions; |
|
188 |
||
189 |
// The number of regions we could create by expansion. |
|
190 |
size_t _expansion_regions; |
|
191 |
||
192 |
// Return the number of free regions in the heap (by direct counting.) |
|
193 |
size_t count_free_regions(); |
|
194 |
// Return the number of free regions on the free and unclean lists. |
|
195 |
size_t count_free_regions_list(); |
|
196 |
||
197 |
// The block offset table for the G1 heap. |
|
198 |
G1BlockOffsetSharedArray* _bot_shared; |
|
199 |
||
200 |
// Move all of the regions off the free lists, then rebuild those free |
|
201 |
// lists, before and after full GC. |
|
202 |
void tear_down_region_lists(); |
|
203 |
void rebuild_region_lists(); |
|
204 |
// This sets all non-empty regions to need zero-fill (which they will if |
|
205 |
// they are empty after full collection.) |
|
206 |
void set_used_regions_to_need_zero_fill(); |
|
207 |
||
208 |
// The sequence of all heap regions in the heap. |
|
209 |
HeapRegionSeq* _hrs; |
|
210 |
||
211 |
// The region from which normal-sized objects are currently being |
|
212 |
// allocated. May be NULL. |
|
213 |
HeapRegion* _cur_alloc_region; |
|
214 |
||
215 |
// Postcondition: cur_alloc_region == NULL. |
|
216 |
void abandon_cur_alloc_region(); |
|
2248 | 217 |
void abandon_gc_alloc_regions(); |
1374 | 218 |
|
219 |
// The to-space memory regions into which objects are being copied during |
|
220 |
// a GC. |
|
221 |
HeapRegion* _gc_alloc_regions[GCAllocPurposeCount]; |
|
2009 | 222 |
size_t _gc_alloc_region_counts[GCAllocPurposeCount]; |
2248 | 223 |
// These are the regions, one per GCAllocPurpose, that are half-full |
224 |
// at the end of a collection and that we want to reuse during the |
|
225 |
// next collection. |
|
226 |
HeapRegion* _retained_gc_alloc_regions[GCAllocPurposeCount]; |
|
227 |
// This specifies whether we will keep the last half-full region at |
|
228 |
// the end of a collection so that it can be reused during the next |
|
229 |
// collection (this is specified per GCAllocPurpose) |
|
230 |
bool _retain_gc_alloc_region[GCAllocPurposeCount]; |
|
1374 | 231 |
|
232 |
// A list of the regions that have been set to be alloc regions in the |
|
233 |
// current collection. |
|
234 |
HeapRegion* _gc_alloc_region_list; |
|
235 |
||
236 |
// When called by par thread, require par_alloc_during_gc_lock() to be held. |
|
237 |
void push_gc_alloc_region(HeapRegion* hr); |
|
238 |
||
239 |
// This should only be called single-threaded. Undeclares all GC alloc |
|
240 |
// regions. |
|
241 |
void forget_alloc_region_list(); |
|
242 |
||
243 |
// Should be used to set an alloc region, because there's other |
|
244 |
// associated bookkeeping. |
|
245 |
void set_gc_alloc_region(int purpose, HeapRegion* r); |
|
246 |
||
247 |
// Check well-formedness of alloc region list. |
|
248 |
bool check_gc_alloc_regions(); |
|
249 |
||
250 |
// Outside of GC pauses, the number of bytes used in all regions other |
|
251 |
// than the current allocation region. |
|
252 |
size_t _summary_bytes_used; |
|
253 |
||
1902 | 254 |
// This is used for a quick test on whether a reference points into |
255 |
// the collection set or not. Basically, we have an array, with one |
|
256 |
// byte per region, and that byte denotes whether the corresponding |
|
257 |
// region is in the collection set or not. The entry corresponding |
|
258 |
// the bottom of the heap, i.e., region 0, is pointed to by |
|
259 |
// _in_cset_fast_test_base. The _in_cset_fast_test field has been |
|
260 |
// biased so that it actually points to address 0 of the address |
|
261 |
// space, to make the test as fast as possible (we can simply shift |
|
262 |
// the address to address into it, instead of having to subtract the |
|
263 |
// bottom of the heap from the address before shifting it; basically |
|
264 |
// it works in the same way the card table works). |
|
265 |
bool* _in_cset_fast_test; |
|
266 |
||
267 |
// The allocated array used for the fast test on whether a reference |
|
268 |
// points into the collection set or not. This field is also used to |
|
269 |
// free the array. |
|
270 |
bool* _in_cset_fast_test_base; |
|
271 |
||
272 |
// The length of the _in_cset_fast_test_base array. |
|
273 |
size_t _in_cset_fast_test_length; |
|
274 |
||
1385
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
275 |
volatile unsigned _gc_time_stamp; |
1374 | 276 |
|
277 |
size_t* _surviving_young_words; |
|
278 |
||
279 |
void setup_surviving_young_words(); |
|
280 |
void update_surviving_young_words(size_t* surv_young_words); |
|
281 |
void cleanup_surviving_young_words(); |
|
282 |
||
283 |
protected: |
|
284 |
||
285 |
// Returns "true" iff none of the gc alloc regions have any allocations |
|
286 |
// since the last call to "save_marks". |
|
287 |
bool all_alloc_regions_no_allocs_since_save_marks(); |
|
2009 | 288 |
// Perform finalization stuff on all allocation regions. |
289 |
void retire_all_alloc_regions(); |
|
1374 | 290 |
|
291 |
// The number of regions allocated to hold humongous objects. |
|
292 |
int _num_humongous_regions; |
|
293 |
YoungList* _young_list; |
|
294 |
||
295 |
// The current policy object for the collector. |
|
296 |
G1CollectorPolicy* _g1_policy; |
|
297 |
||
298 |
// Parallel allocation lock to protect the current allocation region. |
|
299 |
Mutex _par_alloc_during_gc_lock; |
|
300 |
Mutex* par_alloc_during_gc_lock() { return &_par_alloc_during_gc_lock; } |
|
301 |
||
302 |
// If possible/desirable, allocate a new HeapRegion for normal object |
|
303 |
// allocation sufficient for an allocation of the given "word_size". |
|
304 |
// If "do_expand" is true, will attempt to expand the heap if necessary |
|
305 |
// to to satisfy the request. If "zero_filled" is true, requires a |
|
306 |
// zero-filled region. |
|
307 |
// (Returning NULL will trigger a GC.) |
|
308 |
virtual HeapRegion* newAllocRegion_work(size_t word_size, |
|
309 |
bool do_expand, |
|
310 |
bool zero_filled); |
|
311 |
||
312 |
virtual HeapRegion* newAllocRegion(size_t word_size, |
|
313 |
bool zero_filled = true) { |
|
314 |
return newAllocRegion_work(word_size, false, zero_filled); |
|
315 |
} |
|
316 |
virtual HeapRegion* newAllocRegionWithExpansion(int purpose, |
|
317 |
size_t word_size, |
|
318 |
bool zero_filled = true); |
|
319 |
||
320 |
// Attempt to allocate an object of the given (very large) "word_size". |
|
321 |
// Returns "NULL" on failure. |
|
322 |
virtual HeapWord* humongousObjAllocate(size_t word_size); |
|
323 |
||
324 |
// If possible, allocate a block of the given word_size, else return "NULL". |
|
325 |
// Returning NULL will trigger GC or heap expansion. |
|
326 |
// These two methods have rather awkward pre- and |
|
327 |
// post-conditions. If they are called outside a safepoint, then |
|
328 |
// they assume that the caller is holding the heap lock. Upon return |
|
329 |
// they release the heap lock, if they are returning a non-NULL |
|
330 |
// value. attempt_allocation_slow() also dirties the cards of a |
|
331 |
// newly-allocated young region after it releases the heap |
|
332 |
// lock. This change in interface was the neatest way to achieve |
|
333 |
// this card dirtying without affecting mem_allocate(), which is a |
|
334 |
// more frequently called method. We tried two or three different |
|
335 |
// approaches, but they were even more hacky. |
|
336 |
HeapWord* attempt_allocation(size_t word_size, |
|
337 |
bool permit_collection_pause = true); |
|
338 |
||
339 |
HeapWord* attempt_allocation_slow(size_t word_size, |
|
340 |
bool permit_collection_pause = true); |
|
341 |
||
342 |
// Allocate blocks during garbage collection. Will ensure an |
|
343 |
// allocation region, either by picking one or expanding the |
|
344 |
// heap, and then allocate a block of the given size. The block |
|
345 |
// may not be a humongous - it must fit into a single heap region. |
|
346 |
HeapWord* allocate_during_gc(GCAllocPurpose purpose, size_t word_size); |
|
347 |
HeapWord* par_allocate_during_gc(GCAllocPurpose purpose, size_t word_size); |
|
348 |
||
349 |
HeapWord* allocate_during_gc_slow(GCAllocPurpose purpose, |
|
350 |
HeapRegion* alloc_region, |
|
351 |
bool par, |
|
352 |
size_t word_size); |
|
353 |
||
354 |
// Ensure that no further allocations can happen in "r", bearing in mind |
|
355 |
// that parallel threads might be attempting allocations. |
|
356 |
void par_allocate_remaining_space(HeapRegion* r); |
|
357 |
||
2009 | 358 |
// Retires an allocation region when it is full or at the end of a |
359 |
// GC pause. |
|
360 |
void retire_alloc_region(HeapRegion* alloc_region, bool par); |
|
361 |
||
1374 | 362 |
// Helper function for two callbacks below. |
363 |
// "full", if true, indicates that the GC is for a System.gc() request, |
|
364 |
// and should collect the entire heap. If "clear_all_soft_refs" is true, |
|
365 |
// all soft references are cleared during the GC. If "full" is false, |
|
366 |
// "word_size" describes the allocation that the GC should |
|
367 |
// attempt (at least) to satisfy. |
|
368 |
void do_collection(bool full, bool clear_all_soft_refs, |
|
369 |
size_t word_size); |
|
370 |
||
371 |
// Callback from VM_G1CollectFull operation. |
|
372 |
// Perform a full collection. |
|
373 |
void do_full_collection(bool clear_all_soft_refs); |
|
374 |
||
375 |
// Resize the heap if necessary after a full collection. If this is |
|
376 |
// after a collect-for allocation, "word_size" is the allocation size, |
|
377 |
// and will be considered part of the used portion of the heap. |
|
378 |
void resize_if_necessary_after_full_collection(size_t word_size); |
|
379 |
||
380 |
// Callback from VM_G1CollectForAllocation operation. |
|
381 |
// This function does everything necessary/possible to satisfy a |
|
382 |
// failed allocation request (including collection, expansion, etc.) |
|
383 |
HeapWord* satisfy_failed_allocation(size_t word_size); |
|
384 |
||
385 |
// Attempting to expand the heap sufficiently |
|
386 |
// to support an allocation of the given "word_size". If |
|
387 |
// successful, perform the allocation and return the address of the |
|
388 |
// allocated block, or else "NULL". |
|
389 |
virtual HeapWord* expand_and_allocate(size_t word_size); |
|
390 |
||
391 |
public: |
|
392 |
// Expand the garbage-first heap by at least the given size (in bytes!). |
|
393 |
// (Rounds up to a HeapRegion boundary.) |
|
394 |
virtual void expand(size_t expand_bytes); |
|
395 |
||
396 |
// Do anything common to GC's. |
|
397 |
virtual void gc_prologue(bool full); |
|
398 |
virtual void gc_epilogue(bool full); |
|
399 |
||
1902 | 400 |
// We register a region with the fast "in collection set" test. We |
401 |
// simply set to true the array slot corresponding to this region. |
|
402 |
void register_region_with_in_cset_fast_test(HeapRegion* r) { |
|
403 |
assert(_in_cset_fast_test_base != NULL, "sanity"); |
|
404 |
assert(r->in_collection_set(), "invariant"); |
|
405 |
int index = r->hrs_index(); |
|
406 |
assert(0 <= (size_t) index && (size_t) index < _in_cset_fast_test_length, |
|
407 |
"invariant"); |
|
408 |
assert(!_in_cset_fast_test_base[index], "invariant"); |
|
409 |
_in_cset_fast_test_base[index] = true; |
|
410 |
} |
|
411 |
||
412 |
// This is a fast test on whether a reference points into the |
|
413 |
// collection set or not. It does not assume that the reference |
|
414 |
// points into the heap; if it doesn't, it will return false. |
|
415 |
bool in_cset_fast_test(oop obj) { |
|
416 |
assert(_in_cset_fast_test != NULL, "sanity"); |
|
417 |
if (_g1_committed.contains((HeapWord*) obj)) { |
|
418 |
// no need to subtract the bottom of the heap from obj, |
|
419 |
// _in_cset_fast_test is biased |
|
420 |
size_t index = ((size_t) obj) >> HeapRegion::LogOfHRGrainBytes; |
|
421 |
bool ret = _in_cset_fast_test[index]; |
|
422 |
// let's make sure the result is consistent with what the slower |
|
423 |
// test returns |
|
424 |
assert( ret || !obj_in_cs(obj), "sanity"); |
|
425 |
assert(!ret || obj_in_cs(obj), "sanity"); |
|
426 |
return ret; |
|
427 |
} else { |
|
428 |
return false; |
|
429 |
} |
|
430 |
} |
|
431 |
||
1374 | 432 |
protected: |
433 |
||
434 |
// Shrink the garbage-first heap by at most the given size (in bytes!). |
|
435 |
// (Rounds down to a HeapRegion boundary.) |
|
436 |
virtual void shrink(size_t expand_bytes); |
|
437 |
void shrink_helper(size_t expand_bytes); |
|
438 |
||
439 |
// Do an incremental collection: identify a collection set, and evacuate |
|
440 |
// its live objects elsewhere. |
|
441 |
virtual void do_collection_pause(); |
|
442 |
||
443 |
// The guts of the incremental collection pause, executed by the vm |
|
2344 | 444 |
// thread. |
445 |
virtual void do_collection_pause_at_safepoint(); |
|
1374 | 446 |
|
447 |
// Actually do the work of evacuating the collection set. |
|
448 |
virtual void evacuate_collection_set(); |
|
449 |
||
450 |
// If this is an appropriate right time, do a collection pause. |
|
451 |
// The "word_size" argument, if non-zero, indicates the size of an |
|
452 |
// allocation request that is prompting this query. |
|
453 |
void do_collection_pause_if_appropriate(size_t word_size); |
|
454 |
||
455 |
// The g1 remembered set of the heap. |
|
456 |
G1RemSet* _g1_rem_set; |
|
457 |
// And it's mod ref barrier set, used to track updates for the above. |
|
458 |
ModRefBarrierSet* _mr_bs; |
|
459 |
||
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
460 |
// A set of cards that cover the objects for which the Rsets should be updated |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
461 |
// concurrently after the collection. |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
462 |
DirtyCardQueueSet _dirty_card_queue_set; |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
463 |
|
1374 | 464 |
// The Heap Region Rem Set Iterator. |
465 |
HeapRegionRemSetIterator** _rem_set_iterator; |
|
466 |
||
467 |
// The closure used to refine a single card. |
|
468 |
RefineCardTableEntryClosure* _refine_cte_cl; |
|
469 |
||
470 |
// A function to check the consistency of dirty card logs. |
|
471 |
void check_ct_logs_at_safepoint(); |
|
472 |
||
473 |
// After a collection pause, make the regions in the CS into free |
|
474 |
// regions. |
|
475 |
void free_collection_set(HeapRegion* cs_head); |
|
476 |
||
477 |
// Applies "scan_non_heap_roots" to roots outside the heap, |
|
478 |
// "scan_rs" to roots inside the heap (having done "set_region" to |
|
479 |
// indicate the region in which the root resides), and does "scan_perm" |
|
480 |
// (setting the generation to the perm generation.) If "scan_rs" is |
|
481 |
// NULL, then this step is skipped. The "worker_i" |
|
482 |
// param is for use with parallel roots processing, and should be |
|
483 |
// the "i" of the calling parallel worker thread's work(i) function. |
|
484 |
// In the sequential case this param will be ignored. |
|
485 |
void g1_process_strong_roots(bool collecting_perm_gen, |
|
486 |
SharedHeap::ScanningOption so, |
|
487 |
OopClosure* scan_non_heap_roots, |
|
488 |
OopsInHeapRegionClosure* scan_rs, |
|
489 |
OopsInHeapRegionClosure* scan_so, |
|
490 |
OopsInGenClosure* scan_perm, |
|
491 |
int worker_i); |
|
492 |
||
493 |
void scan_scan_only_set(OopsInHeapRegionClosure* oc, |
|
494 |
int worker_i); |
|
495 |
void scan_scan_only_region(HeapRegion* hr, |
|
496 |
OopsInHeapRegionClosure* oc, |
|
497 |
int worker_i); |
|
498 |
||
499 |
// Apply "blk" to all the weak roots of the system. These include |
|
500 |
// JNI weak roots, the code cache, system dictionary, symbol table, |
|
501 |
// string table, and referents of reachable weak refs. |
|
502 |
void g1_process_weak_roots(OopClosure* root_closure, |
|
503 |
OopClosure* non_root_closure); |
|
504 |
||
505 |
// Invoke "save_marks" on all heap regions. |
|
506 |
void save_marks(); |
|
507 |
||
508 |
// Free a heap region. |
|
509 |
void free_region(HeapRegion* hr); |
|
510 |
// A component of "free_region", exposed for 'batching'. |
|
511 |
// All the params after "hr" are out params: the used bytes of the freed |
|
512 |
// region(s), the number of H regions cleared, the number of regions |
|
513 |
// freed, and pointers to the head and tail of a list of freed contig |
|
514 |
// regions, linked throught the "next_on_unclean_list" field. |
|
515 |
void free_region_work(HeapRegion* hr, |
|
516 |
size_t& pre_used, |
|
517 |
size_t& cleared_h, |
|
518 |
size_t& freed_regions, |
|
519 |
UncleanRegionList* list, |
|
520 |
bool par = false); |
|
521 |
||
522 |
||
523 |
// The concurrent marker (and the thread it runs in.) |
|
524 |
ConcurrentMark* _cm; |
|
525 |
ConcurrentMarkThread* _cmThread; |
|
526 |
bool _mark_in_progress; |
|
527 |
||
528 |
// The concurrent refiner. |
|
529 |
ConcurrentG1Refine* _cg1r; |
|
530 |
||
531 |
// The concurrent zero-fill thread. |
|
532 |
ConcurrentZFThread* _czft; |
|
533 |
||
534 |
// The parallel task queues |
|
535 |
RefToScanQueueSet *_task_queues; |
|
536 |
||
537 |
// True iff a evacuation has failed in the current collection. |
|
538 |
bool _evacuation_failed; |
|
539 |
||
540 |
// Set the attribute indicating whether evacuation has failed in the |
|
541 |
// current collection. |
|
542 |
void set_evacuation_failed(bool b) { _evacuation_failed = b; } |
|
543 |
||
544 |
// Failed evacuations cause some logical from-space objects to have |
|
545 |
// forwarding pointers to themselves. Reset them. |
|
546 |
void remove_self_forwarding_pointers(); |
|
547 |
||
548 |
// When one is non-null, so is the other. Together, they each pair is |
|
549 |
// an object with a preserved mark, and its mark value. |
|
550 |
GrowableArray<oop>* _objs_with_preserved_marks; |
|
551 |
GrowableArray<markOop>* _preserved_marks_of_objs; |
|
552 |
||
553 |
// Preserve the mark of "obj", if necessary, in preparation for its mark |
|
554 |
// word being overwritten with a self-forwarding-pointer. |
|
555 |
void preserve_mark_if_necessary(oop obj, markOop m); |
|
556 |
||
557 |
// The stack of evac-failure objects left to be scanned. |
|
558 |
GrowableArray<oop>* _evac_failure_scan_stack; |
|
559 |
// The closure to apply to evac-failure objects. |
|
560 |
||
561 |
OopsInHeapRegionClosure* _evac_failure_closure; |
|
562 |
// Set the field above. |
|
563 |
void |
|
564 |
set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_closure) { |
|
565 |
_evac_failure_closure = evac_failure_closure; |
|
566 |
} |
|
567 |
||
568 |
// Push "obj" on the scan stack. |
|
569 |
void push_on_evac_failure_scan_stack(oop obj); |
|
570 |
// Process scan stack entries until the stack is empty. |
|
571 |
void drain_evac_failure_scan_stack(); |
|
572 |
// True iff an invocation of "drain_scan_stack" is in progress; to |
|
573 |
// prevent unnecessary recursion. |
|
574 |
bool _drain_in_progress; |
|
575 |
||
576 |
// Do any necessary initialization for evacuation-failure handling. |
|
577 |
// "cl" is the closure that will be used to process evac-failure |
|
578 |
// objects. |
|
579 |
void init_for_evac_failure(OopsInHeapRegionClosure* cl); |
|
580 |
// Do any necessary cleanup for evacuation-failure handling data |
|
581 |
// structures. |
|
582 |
void finalize_for_evac_failure(); |
|
583 |
||
584 |
// An attempt to evacuate "obj" has failed; take necessary steps. |
|
585 |
void handle_evacuation_failure(oop obj); |
|
586 |
oop handle_evacuation_failure_par(OopsInHeapRegionClosure* cl, oop obj); |
|
587 |
void handle_evacuation_failure_common(oop obj, markOop m); |
|
588 |
||
589 |
||
590 |
// Ensure that the relevant gc_alloc regions are set. |
|
591 |
void get_gc_alloc_regions(); |
|
2248 | 592 |
// We're done with GC alloc regions. We are going to tear down the |
593 |
// gc alloc list and remove the gc alloc tag from all the regions on |
|
594 |
// that list. However, we will also retain the last (i.e., the one |
|
595 |
// that is half-full) GC alloc region, per GCAllocPurpose, for |
|
596 |
// possible reuse during the next collection, provided |
|
597 |
// _retain_gc_alloc_region[] indicates that it should be the |
|
598 |
// case. Said regions are kept in the _retained_gc_alloc_regions[] |
|
599 |
// array. If the parameter totally is set, we will not retain any |
|
600 |
// regions, irrespective of what _retain_gc_alloc_region[] |
|
601 |
// indicates. |
|
602 |
void release_gc_alloc_regions(bool totally); |
|
603 |
#ifndef PRODUCT |
|
604 |
// Useful for debugging. |
|
605 |
void print_gc_alloc_regions(); |
|
606 |
#endif // !PRODUCT |
|
1374 | 607 |
|
608 |
// ("Weak") Reference processing support |
|
609 |
ReferenceProcessor* _ref_processor; |
|
610 |
||
611 |
enum G1H_process_strong_roots_tasks { |
|
612 |
G1H_PS_mark_stack_oops_do, |
|
613 |
G1H_PS_refProcessor_oops_do, |
|
614 |
// Leave this one last. |
|
615 |
G1H_PS_NumElements |
|
616 |
}; |
|
617 |
||
618 |
SubTasksDone* _process_strong_tasks; |
|
619 |
||
620 |
// List of regions which require zero filling. |
|
621 |
UncleanRegionList _unclean_region_list; |
|
622 |
bool _unclean_regions_coming; |
|
623 |
||
624 |
public: |
|
625 |
void set_refine_cte_cl_concurrency(bool concurrent); |
|
626 |
||
627 |
RefToScanQueue *task_queue(int i); |
|
628 |
||
2142
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
629 |
// A set of cards where updates happened during the GC |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
630 |
DirtyCardQueueSet& dirty_card_queue_set() { return _dirty_card_queue_set; } |
032f4652700c
6720309: G1: don't synchronously update RSet during evacuation pauses
iveresov
parents:
2009
diff
changeset
|
631 |
|
1374 | 632 |
// Create a G1CollectedHeap with the specified policy. |
633 |
// Must call the initialize method afterwards. |
|
634 |
// May not return if something goes wrong. |
|
635 |
G1CollectedHeap(G1CollectorPolicy* policy); |
|
636 |
||
637 |
// Initialize the G1CollectedHeap to have the initial and |
|
638 |
// maximum sizes, permanent generation, and remembered and barrier sets |
|
639 |
// specified by the policy object. |
|
640 |
jint initialize(); |
|
641 |
||
642 |
void ref_processing_init(); |
|
643 |
||
644 |
void set_par_threads(int t) { |
|
645 |
SharedHeap::set_par_threads(t); |
|
646 |
_process_strong_tasks->set_par_threads(t); |
|
647 |
} |
|
648 |
||
649 |
virtual CollectedHeap::Name kind() const { |
|
650 |
return CollectedHeap::G1CollectedHeap; |
|
651 |
} |
|
652 |
||
653 |
// The current policy object for the collector. |
|
654 |
G1CollectorPolicy* g1_policy() const { return _g1_policy; } |
|
655 |
||
656 |
// Adaptive size policy. No such thing for g1. |
|
657 |
virtual AdaptiveSizePolicy* size_policy() { return NULL; } |
|
658 |
||
659 |
// The rem set and barrier set. |
|
660 |
G1RemSet* g1_rem_set() const { return _g1_rem_set; } |
|
661 |
ModRefBarrierSet* mr_bs() const { return _mr_bs; } |
|
662 |
||
663 |
// The rem set iterator. |
|
664 |
HeapRegionRemSetIterator* rem_set_iterator(int i) { |
|
665 |
return _rem_set_iterator[i]; |
|
666 |
} |
|
667 |
||
668 |
HeapRegionRemSetIterator* rem_set_iterator() { |
|
669 |
return _rem_set_iterator[0]; |
|
670 |
} |
|
671 |
||
672 |
unsigned get_gc_time_stamp() { |
|
673 |
return _gc_time_stamp; |
|
674 |
} |
|
675 |
||
676 |
void reset_gc_time_stamp() { |
|
677 |
_gc_time_stamp = 0; |
|
1385
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
678 |
OrderAccess::fence(); |
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
679 |
} |
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
680 |
|
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
681 |
void increment_gc_time_stamp() { |
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
682 |
++_gc_time_stamp; |
1751733b089b
6723570: G1: assertion failure: p == current_top or oop(p)->is_oop(),"p is not a block start" (revisited!)
iveresov
parents:
1374
diff
changeset
|
683 |
OrderAccess::fence(); |
1374 | 684 |
} |
685 |
||
686 |
void iterate_dirty_card_closure(bool concurrent, int worker_i); |
|
687 |
||
688 |
// The shared block offset table array. |
|
689 |
G1BlockOffsetSharedArray* bot_shared() const { return _bot_shared; } |
|
690 |
||
691 |
// Reference Processing accessor |
|
692 |
ReferenceProcessor* ref_processor() { return _ref_processor; } |
|
693 |
||
694 |
// Reserved (g1 only; super method includes perm), capacity and the used |
|
695 |
// portion in bytes. |
|
696 |
size_t g1_reserved_obj_bytes() { return _g1_reserved.byte_size(); } |
|
697 |
virtual size_t capacity() const; |
|
698 |
virtual size_t used() const; |
|
699 |
size_t recalculate_used() const; |
|
700 |
#ifndef PRODUCT |
|
701 |
size_t recalculate_used_regions() const; |
|
702 |
#endif // PRODUCT |
|
703 |
||
704 |
// These virtual functions do the actual allocation. |
|
705 |
virtual HeapWord* mem_allocate(size_t word_size, |
|
706 |
bool is_noref, |
|
707 |
bool is_tlab, |
|
708 |
bool* gc_overhead_limit_was_exceeded); |
|
709 |
||
710 |
// Some heaps may offer a contiguous region for shared non-blocking |
|
711 |
// allocation, via inlined code (by exporting the address of the top and |
|
712 |
// end fields defining the extent of the contiguous allocation region.) |
|
713 |
// But G1CollectedHeap doesn't yet support this. |
|
714 |
||
715 |
// Return an estimate of the maximum allocation that could be performed |
|
716 |
// without triggering any collection or expansion activity. In a |
|
717 |
// generational collector, for example, this is probably the largest |
|
718 |
// allocation that could be supported (without expansion) in the youngest |
|
719 |
// generation. It is "unsafe" because no locks are taken; the result |
|
720 |
// should be treated as an approximation, not a guarantee, for use in |
|
721 |
// heuristic resizing decisions. |
|
722 |
virtual size_t unsafe_max_alloc(); |
|
723 |
||
724 |
virtual bool is_maximal_no_gc() const { |
|
725 |
return _g1_storage.uncommitted_size() == 0; |
|
726 |
} |
|
727 |
||
728 |
// The total number of regions in the heap. |
|
729 |
size_t n_regions(); |
|
730 |
||
731 |
// The number of regions that are completely free. |
|
732 |
size_t max_regions(); |
|
733 |
||
734 |
// The number of regions that are completely free. |
|
735 |
size_t free_regions(); |
|
736 |
||
737 |
// The number of regions that are not completely free. |
|
738 |
size_t used_regions() { return n_regions() - free_regions(); } |
|
739 |
||
740 |
// True iff the ZF thread should run. |
|
741 |
bool should_zf(); |
|
742 |
||
743 |
// The number of regions available for "regular" expansion. |
|
744 |
size_t expansion_regions() { return _expansion_regions; } |
|
745 |
||
746 |
#ifndef PRODUCT |
|
747 |
bool regions_accounted_for(); |
|
748 |
bool print_region_accounting_info(); |
|
749 |
void print_region_counts(); |
|
750 |
#endif |
|
751 |
||
752 |
HeapRegion* alloc_region_from_unclean_list(bool zero_filled); |
|
753 |
HeapRegion* alloc_region_from_unclean_list_locked(bool zero_filled); |
|
754 |
||
755 |
void put_region_on_unclean_list(HeapRegion* r); |
|
756 |
void put_region_on_unclean_list_locked(HeapRegion* r); |
|
757 |
||
758 |
void prepend_region_list_on_unclean_list(UncleanRegionList* list); |
|
759 |
void prepend_region_list_on_unclean_list_locked(UncleanRegionList* list); |
|
760 |
||
761 |
void set_unclean_regions_coming(bool b); |
|
762 |
void set_unclean_regions_coming_locked(bool b); |
|
763 |
// Wait for cleanup to be complete. |
|
764 |
void wait_for_cleanup_complete(); |
|
765 |
// Like above, but assumes that the calling thread owns the Heap_lock. |
|
766 |
void wait_for_cleanup_complete_locked(); |
|
767 |
||
768 |
// Return the head of the unclean list. |
|
769 |
HeapRegion* peek_unclean_region_list_locked(); |
|
770 |
// Remove and return the head of the unclean list. |
|
771 |
HeapRegion* pop_unclean_region_list_locked(); |
|
772 |
||
773 |
// List of regions which are zero filled and ready for allocation. |
|
774 |
HeapRegion* _free_region_list; |
|
775 |
// Number of elements on the free list. |
|
776 |
size_t _free_region_list_size; |
|
777 |
||
778 |
// If the head of the unclean list is ZeroFilled, move it to the free |
|
779 |
// list. |
|
780 |
bool move_cleaned_region_to_free_list_locked(); |
|
781 |
bool move_cleaned_region_to_free_list(); |
|
782 |
||
783 |
void put_free_region_on_list_locked(HeapRegion* r); |
|
784 |
void put_free_region_on_list(HeapRegion* r); |
|
785 |
||
786 |
// Remove and return the head element of the free list. |
|
787 |
HeapRegion* pop_free_region_list_locked(); |
|
788 |
||
789 |
// If "zero_filled" is true, we first try the free list, then we try the |
|
790 |
// unclean list, zero-filling the result. If "zero_filled" is false, we |
|
791 |
// first try the unclean list, then the zero-filled list. |
|
792 |
HeapRegion* alloc_free_region_from_lists(bool zero_filled); |
|
793 |
||
794 |
// Verify the integrity of the region lists. |
|
795 |
void remove_allocated_regions_from_lists(); |
|
796 |
bool verify_region_lists(); |
|
797 |
bool verify_region_lists_locked(); |
|
798 |
size_t unclean_region_list_length(); |
|
799 |
size_t free_region_list_length(); |
|
800 |
||
801 |
// Perform a collection of the heap; intended for use in implementing |
|
802 |
// "System.gc". This probably implies as full a collection as the |
|
803 |
// "CollectedHeap" supports. |
|
804 |
virtual void collect(GCCause::Cause cause); |
|
805 |
||
806 |
// The same as above but assume that the caller holds the Heap_lock. |
|
807 |
void collect_locked(GCCause::Cause cause); |
|
808 |
||
809 |
// This interface assumes that it's being called by the |
|
810 |
// vm thread. It collects the heap assuming that the |
|
811 |
// heap lock is already held and that we are executing in |
|
812 |
// the context of the vm thread. |
|
813 |
virtual void collect_as_vm_thread(GCCause::Cause cause); |
|
814 |
||
815 |
// True iff a evacuation has failed in the most-recent collection. |
|
816 |
bool evacuation_failed() { return _evacuation_failed; } |
|
817 |
||
818 |
// Free a region if it is totally full of garbage. Returns the number of |
|
819 |
// bytes freed (0 ==> didn't free it). |
|
820 |
size_t free_region_if_totally_empty(HeapRegion *hr); |
|
821 |
void free_region_if_totally_empty_work(HeapRegion *hr, |
|
822 |
size_t& pre_used, |
|
823 |
size_t& cleared_h_regions, |
|
824 |
size_t& freed_regions, |
|
825 |
UncleanRegionList* list, |
|
826 |
bool par = false); |
|
827 |
||
828 |
// If we've done free region work that yields the given changes, update |
|
829 |
// the relevant global variables. |
|
830 |
void finish_free_region_work(size_t pre_used, |
|
831 |
size_t cleared_h_regions, |
|
832 |
size_t freed_regions, |
|
833 |
UncleanRegionList* list); |
|
834 |
||
835 |
||
836 |
// Returns "TRUE" iff "p" points into the allocated area of the heap. |
|
837 |
virtual bool is_in(const void* p) const; |
|
838 |
||
839 |
// Return "TRUE" iff the given object address is within the collection |
|
840 |
// set. |
|
841 |
inline bool obj_in_cs(oop obj); |
|
842 |
||
843 |
// Return "TRUE" iff the given object address is in the reserved |
|
844 |
// region of g1 (excluding the permanent generation). |
|
845 |
bool is_in_g1_reserved(const void* p) const { |
|
846 |
return _g1_reserved.contains(p); |
|
847 |
} |
|
848 |
||
849 |
// Returns a MemRegion that corresponds to the space that has been |
|
850 |
// committed in the heap |
|
851 |
MemRegion g1_committed() { |
|
852 |
return _g1_committed; |
|
853 |
} |
|
854 |
||
855 |
NOT_PRODUCT( bool is_in_closed_subset(const void* p) const; ) |
|
856 |
||
857 |
// Dirty card table entries covering a list of young regions. |
|
858 |
void dirtyCardsForYoungRegions(CardTableModRefBS* ct_bs, HeapRegion* list); |
|
859 |
||
860 |
// This resets the card table to all zeros. It is used after |
|
861 |
// a collection pause which used the card table to claim cards. |
|
862 |
void cleanUpCardTable(); |
|
863 |
||
864 |
// Iteration functions. |
|
865 |
||
866 |
// Iterate over all the ref-containing fields of all objects, calling |
|
867 |
// "cl.do_oop" on each. |
|
868 |
virtual void oop_iterate(OopClosure* cl); |
|
869 |
||
870 |
// Same as above, restricted to a memory region. |
|
871 |
virtual void oop_iterate(MemRegion mr, OopClosure* cl); |
|
872 |
||
873 |
// Iterate over all objects, calling "cl.do_object" on each. |
|
874 |
virtual void object_iterate(ObjectClosure* cl); |
|
1893
c82e388e17c5
6689653: JMapPerm fails with UseConcMarkSweepIncGC and compressed oops off
jmasa
parents:
1422
diff
changeset
|
875 |
virtual void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); } |
1374 | 876 |
|
877 |
// Iterate over all objects allocated since the last collection, calling |
|
878 |
// "cl.do_object" on each. The heap must have been initialized properly |
|
879 |
// to support this function, or else this call will fail. |
|
880 |
virtual void object_iterate_since_last_GC(ObjectClosure* cl); |
|
881 |
||
882 |
// Iterate over all spaces in use in the heap, in ascending address order. |
|
883 |
virtual void space_iterate(SpaceClosure* cl); |
|
884 |
||
885 |
// Iterate over heap regions, in address order, terminating the |
|
886 |
// iteration early if the "doHeapRegion" method returns "true". |
|
887 |
void heap_region_iterate(HeapRegionClosure* blk); |
|
888 |
||
889 |
// Iterate over heap regions starting with r (or the first region if "r" |
|
890 |
// is NULL), in address order, terminating early if the "doHeapRegion" |
|
891 |
// method returns "true". |
|
892 |
void heap_region_iterate_from(HeapRegion* r, HeapRegionClosure* blk); |
|
893 |
||
894 |
// As above but starting from the region at index idx. |
|
895 |
void heap_region_iterate_from(int idx, HeapRegionClosure* blk); |
|
896 |
||
897 |
HeapRegion* region_at(size_t idx); |
|
898 |
||
899 |
// Divide the heap region sequence into "chunks" of some size (the number |
|
900 |
// of regions divided by the number of parallel threads times some |
|
901 |
// overpartition factor, currently 4). Assumes that this will be called |
|
902 |
// in parallel by ParallelGCThreads worker threads with discinct worker |
|
903 |
// ids in the range [0..max(ParallelGCThreads-1, 1)], that all parallel |
|
904 |
// calls will use the same "claim_value", and that that claim value is |
|
905 |
// different from the claim_value of any heap region before the start of |
|
906 |
// the iteration. Applies "blk->doHeapRegion" to each of the regions, by |
|
907 |
// attempting to claim the first region in each chunk, and, if |
|
908 |
// successful, applying the closure to each region in the chunk (and |
|
909 |
// setting the claim value of the second and subsequent regions of the |
|
910 |
// chunk.) For now requires that "doHeapRegion" always returns "false", |
|
911 |
// i.e., that a closure never attempt to abort a traversal. |
|
912 |
void heap_region_par_iterate_chunked(HeapRegionClosure* blk, |
|
913 |
int worker, |
|
914 |
jint claim_value); |
|
915 |
||
1422 | 916 |
// It resets all the region claim values to the default. |
917 |
void reset_heap_region_claim_values(); |
|
918 |
||
1387 | 919 |
#ifdef ASSERT |
920 |
bool check_heap_region_claim_values(jint claim_value); |
|
921 |
#endif // ASSERT |
|
922 |
||
1374 | 923 |
// Iterate over the regions (if any) in the current collection set. |
924 |
void collection_set_iterate(HeapRegionClosure* blk); |
|
925 |
||
926 |
// As above but starting from region r |
|
927 |
void collection_set_iterate_from(HeapRegion* r, HeapRegionClosure *blk); |
|
928 |
||
929 |
// Returns the first (lowest address) compactible space in the heap. |
|
930 |
virtual CompactibleSpace* first_compactible_space(); |
|
931 |
||
932 |
// A CollectedHeap will contain some number of spaces. This finds the |
|
933 |
// space containing a given address, or else returns NULL. |
|
934 |
virtual Space* space_containing(const void* addr) const; |
|
935 |
||
936 |
// A G1CollectedHeap will contain some number of heap regions. This |
|
937 |
// finds the region containing a given address, or else returns NULL. |
|
938 |
HeapRegion* heap_region_containing(const void* addr) const; |
|
939 |
||
940 |
// Like the above, but requires "addr" to be in the heap (to avoid a |
|
941 |
// null-check), and unlike the above, may return an continuing humongous |
|
942 |
// region. |
|
943 |
HeapRegion* heap_region_containing_raw(const void* addr) const; |
|
944 |
||
945 |
// A CollectedHeap is divided into a dense sequence of "blocks"; that is, |
|
946 |
// each address in the (reserved) heap is a member of exactly |
|
947 |
// one block. The defining characteristic of a block is that it is |
|
948 |
// possible to find its size, and thus to progress forward to the next |
|
949 |
// block. (Blocks may be of different sizes.) Thus, blocks may |
|
950 |
// represent Java objects, or they might be free blocks in a |
|
951 |
// free-list-based heap (or subheap), as long as the two kinds are |
|
952 |
// distinguishable and the size of each is determinable. |
|
953 |
||
954 |
// Returns the address of the start of the "block" that contains the |
|
955 |
// address "addr". We say "blocks" instead of "object" since some heaps |
|
956 |
// may not pack objects densely; a chunk may either be an object or a |
|
957 |
// non-object. |
|
958 |
virtual HeapWord* block_start(const void* addr) const; |
|
959 |
||
960 |
// Requires "addr" to be the start of a chunk, and returns its size. |
|
961 |
// "addr + size" is required to be the start of a new chunk, or the end |
|
962 |
// of the active area of the heap. |
|
963 |
virtual size_t block_size(const HeapWord* addr) const; |
|
964 |
||
965 |
// Requires "addr" to be the start of a block, and returns "TRUE" iff |
|
966 |
// the block is an object. |
|
967 |
virtual bool block_is_obj(const HeapWord* addr) const; |
|
968 |
||
969 |
// Does this heap support heap inspection? (+PrintClassHistogram) |
|
970 |
virtual bool supports_heap_inspection() const { return true; } |
|
971 |
||
972 |
// Section on thread-local allocation buffers (TLABs) |
|
973 |
// See CollectedHeap for semantics. |
|
974 |
||
975 |
virtual bool supports_tlab_allocation() const; |
|
976 |
virtual size_t tlab_capacity(Thread* thr) const; |
|
977 |
virtual size_t unsafe_max_tlab_alloc(Thread* thr) const; |
|
978 |
virtual HeapWord* allocate_new_tlab(size_t size); |
|
979 |
||
980 |
// Can a compiler initialize a new object without store barriers? |
|
981 |
// This permission only extends from the creation of a new object |
|
982 |
// via a TLAB up to the first subsequent safepoint. |
|
983 |
virtual bool can_elide_tlab_store_barriers() const { |
|
984 |
// Since G1's TLAB's may, on occasion, come from non-young regions |
|
985 |
// as well. (Is there a flag controlling that? XXX) |
|
986 |
return false; |
|
987 |
} |
|
988 |
||
989 |
// Can a compiler elide a store barrier when it writes |
|
990 |
// a permanent oop into the heap? Applies when the compiler |
|
991 |
// is storing x to the heap, where x->is_perm() is true. |
|
992 |
virtual bool can_elide_permanent_oop_store_barriers() const { |
|
993 |
// At least until perm gen collection is also G1-ified, at |
|
994 |
// which point this should return false. |
|
995 |
return true; |
|
996 |
} |
|
997 |
||
998 |
virtual bool allocs_are_zero_filled(); |
|
999 |
||
1000 |
// The boundary between a "large" and "small" array of primitives, in |
|
1001 |
// words. |
|
1002 |
virtual size_t large_typearray_limit(); |
|
1003 |
||
1004 |
// Returns "true" iff the given word_size is "very large". |
|
1005 |
static bool isHumongous(size_t word_size) { |
|
1006 |
return word_size >= VeryLargeInWords; |
|
1007 |
} |
|
1008 |
||
1009 |
// Update mod union table with the set of dirty cards. |
|
1010 |
void updateModUnion(); |
|
1011 |
||
1012 |
// Set the mod union bits corresponding to the given memRegion. Note |
|
1013 |
// that this is always a safe operation, since it doesn't clear any |
|
1014 |
// bits. |
|
1015 |
void markModUnionRange(MemRegion mr); |
|
1016 |
||
1017 |
// Records the fact that a marking phase is no longer in progress. |
|
1018 |
void set_marking_complete() { |
|
1019 |
_mark_in_progress = false; |
|
1020 |
} |
|
1021 |
void set_marking_started() { |
|
1022 |
_mark_in_progress = true; |
|
1023 |
} |
|
1024 |
bool mark_in_progress() { |
|
1025 |
return _mark_in_progress; |
|
1026 |
} |
|
1027 |
||
1028 |
// Print the maximum heap capacity. |
|
1029 |
virtual size_t max_capacity() const; |
|
1030 |
||
1031 |
virtual jlong millis_since_last_gc(); |
|
1032 |
||
1033 |
// Perform any cleanup actions necessary before allowing a verification. |
|
1034 |
virtual void prepare_for_verify(); |
|
1035 |
||
1036 |
// Perform verification. |
|
1037 |
virtual void verify(bool allow_dirty, bool silent); |
|
1038 |
virtual void print() const; |
|
1039 |
virtual void print_on(outputStream* st) const; |
|
1040 |
||
1041 |
virtual void print_gc_threads_on(outputStream* st) const; |
|
1042 |
virtual void gc_threads_do(ThreadClosure* tc) const; |
|
1043 |
||
1044 |
// Override |
|
1045 |
void print_tracing_info() const; |
|
1046 |
||
1047 |
// If "addr" is a pointer into the (reserved?) heap, returns a positive |
|
1048 |
// number indicating the "arena" within the heap in which "addr" falls. |
|
1049 |
// Or else returns 0. |
|
1050 |
virtual int addr_to_arena_id(void* addr) const; |
|
1051 |
||
1052 |
// Convenience function to be used in situations where the heap type can be |
|
1053 |
// asserted to be this type. |
|
1054 |
static G1CollectedHeap* heap(); |
|
1055 |
||
1056 |
void empty_young_list(); |
|
1057 |
bool should_set_young_locked(); |
|
1058 |
||
1059 |
void set_region_short_lived_locked(HeapRegion* hr); |
|
1060 |
// add appropriate methods for any other surv rate groups |
|
1061 |
||
1062 |
void young_list_rs_length_sampling_init() { |
|
1063 |
_young_list->rs_length_sampling_init(); |
|
1064 |
} |
|
1065 |
bool young_list_rs_length_sampling_more() { |
|
1066 |
return _young_list->rs_length_sampling_more(); |
|
1067 |
} |
|
1068 |
void young_list_rs_length_sampling_next() { |
|
1069 |
_young_list->rs_length_sampling_next(); |
|
1070 |
} |
|
1071 |
size_t young_list_sampled_rs_lengths() { |
|
1072 |
return _young_list->sampled_rs_lengths(); |
|
1073 |
} |
|
1074 |
||
1075 |
size_t young_list_length() { return _young_list->length(); } |
|
1076 |
size_t young_list_scan_only_length() { |
|
1077 |
return _young_list->scan_only_length(); } |
|
1078 |
||
1079 |
HeapRegion* pop_region_from_young_list() { |
|
1080 |
return _young_list->pop_region(); |
|
1081 |
} |
|
1082 |
||
1083 |
HeapRegion* young_list_first_region() { |
|
1084 |
return _young_list->first_region(); |
|
1085 |
} |
|
1086 |
||
1087 |
// debugging |
|
1088 |
bool check_young_list_well_formed() { |
|
1089 |
return _young_list->check_list_well_formed(); |
|
1090 |
} |
|
1091 |
bool check_young_list_empty(bool ignore_scan_only_list, |
|
1092 |
bool check_sample = true); |
|
1093 |
||
1094 |
// *** Stuff related to concurrent marking. It's not clear to me that so |
|
1095 |
// many of these need to be public. |
|
1096 |
||
1097 |
// The functions below are helper functions that a subclass of |
|
1098 |
// "CollectedHeap" can use in the implementation of its virtual |
|
1099 |
// functions. |
|
1100 |
// This performs a concurrent marking of the live objects in a |
|
1101 |
// bitmap off to the side. |
|
1102 |
void doConcurrentMark(); |
|
1103 |
||
1104 |
// This is called from the marksweep collector which then does |
|
1105 |
// a concurrent mark and verifies that the results agree with |
|
1106 |
// the stop the world marking. |
|
1107 |
void checkConcurrentMark(); |
|
1108 |
void do_sync_mark(); |
|
1109 |
||
1110 |
bool isMarkedPrev(oop obj) const; |
|
1111 |
bool isMarkedNext(oop obj) const; |
|
1112 |
||
1113 |
// Determine if an object is dead, given the object and also |
|
1114 |
// the region to which the object belongs. An object is dead |
|
1115 |
// iff a) it was not allocated since the last mark and b) it |
|
1116 |
// is not marked. |
|
1117 |
||
1118 |
bool is_obj_dead(const oop obj, const HeapRegion* hr) const { |
|
1119 |
return |
|
1120 |
!hr->obj_allocated_since_prev_marking(obj) && |
|
1121 |
!isMarkedPrev(obj); |
|
1122 |
} |
|
1123 |
||
1124 |
// This is used when copying an object to survivor space. |
|
1125 |
// If the object is marked live, then we mark the copy live. |
|
1126 |
// If the object is allocated since the start of this mark |
|
1127 |
// cycle, then we mark the copy live. |
|
1128 |
// If the object has been around since the previous mark |
|
1129 |
// phase, and hasn't been marked yet during this phase, |
|
1130 |
// then we don't mark it, we just wait for the |
|
1131 |
// current marking cycle to get to it. |
|
1132 |
||
1133 |
// This function returns true when an object has been |
|
1134 |
// around since the previous marking and hasn't yet |
|
1135 |
// been marked during this marking. |
|
1136 |
||
1137 |
bool is_obj_ill(const oop obj, const HeapRegion* hr) const { |
|
1138 |
return |
|
1139 |
!hr->obj_allocated_since_next_marking(obj) && |
|
1140 |
!isMarkedNext(obj); |
|
1141 |
} |
|
1142 |
||
1143 |
// Determine if an object is dead, given only the object itself. |
|
1144 |
// This will find the region to which the object belongs and |
|
1145 |
// then call the region version of the same function. |
|
1146 |
||
1147 |
// Added if it is in permanent gen it isn't dead. |
|
1148 |
// Added if it is NULL it isn't dead. |
|
1149 |
||
1150 |
bool is_obj_dead(oop obj) { |
|
1151 |
HeapRegion* hr = heap_region_containing(obj); |
|
1152 |
if (hr == NULL) { |
|
1153 |
if (Universe::heap()->is_in_permanent(obj)) |
|
1154 |
return false; |
|
1155 |
else if (obj == NULL) return false; |
|
1156 |
else return true; |
|
1157 |
} |
|
1158 |
else return is_obj_dead(obj, hr); |
|
1159 |
} |
|
1160 |
||
1161 |
bool is_obj_ill(oop obj) { |
|
1162 |
HeapRegion* hr = heap_region_containing(obj); |
|
1163 |
if (hr == NULL) { |
|
1164 |
if (Universe::heap()->is_in_permanent(obj)) |
|
1165 |
return false; |
|
1166 |
else if (obj == NULL) return false; |
|
1167 |
else return true; |
|
1168 |
} |
|
1169 |
else return is_obj_ill(obj, hr); |
|
1170 |
} |
|
1171 |
||
1172 |
// The following is just to alert the verification code |
|
1173 |
// that a full collection has occurred and that the |
|
1174 |
// remembered sets are no longer up to date. |
|
1175 |
bool _full_collection; |
|
1176 |
void set_full_collection() { _full_collection = true;} |
|
1177 |
void clear_full_collection() {_full_collection = false;} |
|
1178 |
bool full_collection() {return _full_collection;} |
|
1179 |
||
1180 |
ConcurrentMark* concurrent_mark() const { return _cm; } |
|
1181 |
ConcurrentG1Refine* concurrent_g1_refine() const { return _cg1r; } |
|
1182 |
||
1183 |
public: |
|
1184 |
void stop_conc_gc_threads(); |
|
1185 |
||
1186 |
// <NEW PREDICTION> |
|
1187 |
||
1188 |
double predict_region_elapsed_time_ms(HeapRegion* hr, bool young); |
|
1189 |
void check_if_region_is_too_expensive(double predicted_time_ms); |
|
1190 |
size_t pending_card_num(); |
|
1191 |
size_t max_pending_card_num(); |
|
1192 |
size_t cards_scanned(); |
|
1193 |
||
1194 |
// </NEW PREDICTION> |
|
1195 |
||
1196 |
protected: |
|
1197 |
size_t _max_heap_capacity; |
|
1198 |
||
1199 |
// debug_only(static void check_for_valid_allocation_state();) |
|
1200 |
||
1201 |
public: |
|
1202 |
// Temporary: call to mark things unimplemented for the G1 heap (e.g., |
|
1203 |
// MemoryService). In productization, we can make this assert false |
|
1204 |
// to catch such places (as well as searching for calls to this...) |
|
1205 |
static void g1_unimplemented(); |
|
1206 |
||
1207 |
}; |
|
1208 |
||
1209 |
// Local Variables: *** |
|
1210 |
// c-indentation-style: gnu *** |
|
1211 |
// End: *** |