1 /* |
|
2 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved. |
|
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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
|
20 * or visit www.oracle.com if you need additional information or have any |
|
21 * questions. |
|
22 * |
|
23 */ |
|
24 |
|
25 #include "precompiled.hpp" |
|
26 #include "gc/g1/g1CollectedHeap.inline.hpp" |
|
27 #include "gc/g1/g1ConcurrentMark.inline.hpp" |
|
28 #include "gc/g1/g1CardLiveData.inline.hpp" |
|
29 #include "gc/shared/suspendibleThreadSet.hpp" |
|
30 #include "gc/shared/workgroup.hpp" |
|
31 #include "logging/log.hpp" |
|
32 #include "memory/universe.hpp" |
|
33 #include "runtime/atomic.hpp" |
|
34 #include "runtime/globals.hpp" |
|
35 #include "runtime/os.hpp" |
|
36 #include "utilities/align.hpp" |
|
37 #include "utilities/bitMap.inline.hpp" |
|
38 #include "utilities/debug.hpp" |
|
39 |
|
40 G1CardLiveData::G1CardLiveData() : |
|
41 _max_capacity(0), |
|
42 _cards_per_region(0), |
|
43 _gc_timestamp_at_create(0), |
|
44 _live_regions(NULL), |
|
45 _live_regions_size_in_bits(0), |
|
46 _live_cards(NULL), |
|
47 _live_cards_size_in_bits(0) { |
|
48 } |
|
49 |
|
50 G1CardLiveData::~G1CardLiveData() { |
|
51 free_large_bitmap(_live_cards, _live_cards_size_in_bits); |
|
52 free_large_bitmap(_live_regions, _live_regions_size_in_bits); |
|
53 } |
|
54 |
|
55 G1CardLiveData::bm_word_t* G1CardLiveData::allocate_large_bitmap(size_t size_in_bits) { |
|
56 size_t size_in_words = BitMap::calc_size_in_words(size_in_bits); |
|
57 |
|
58 bm_word_t* map = MmapArrayAllocator<bm_word_t>::allocate(size_in_words, mtGC); |
|
59 |
|
60 return map; |
|
61 } |
|
62 |
|
63 void G1CardLiveData::free_large_bitmap(bm_word_t* bitmap, size_t size_in_bits) { |
|
64 MmapArrayAllocator<bm_word_t>::free(bitmap, BitMap::calc_size_in_words(size_in_bits)); |
|
65 } |
|
66 |
|
67 void G1CardLiveData::initialize(size_t max_capacity, uint num_max_regions) { |
|
68 assert(max_capacity % num_max_regions == 0, |
|
69 "Given capacity must be evenly divisible by region size."); |
|
70 size_t region_size = max_capacity / num_max_regions; |
|
71 assert(region_size % (G1CardTable::card_size * BitsPerWord) == 0, |
|
72 "Region size must be evenly divisible by area covered by a single word."); |
|
73 _max_capacity = max_capacity; |
|
74 _cards_per_region = region_size / G1CardTable::card_size; |
|
75 |
|
76 _live_regions_size_in_bits = live_region_bitmap_size_in_bits(); |
|
77 _live_regions = allocate_large_bitmap(_live_regions_size_in_bits); |
|
78 _live_cards_size_in_bits = live_card_bitmap_size_in_bits(); |
|
79 _live_cards = allocate_large_bitmap(_live_cards_size_in_bits); |
|
80 } |
|
81 |
|
82 void G1CardLiveData::pretouch() { |
|
83 live_cards_bm().pretouch(); |
|
84 live_regions_bm().pretouch(); |
|
85 } |
|
86 |
|
87 size_t G1CardLiveData::live_region_bitmap_size_in_bits() const { |
|
88 return _max_capacity / (_cards_per_region << G1CardTable::card_shift); |
|
89 } |
|
90 |
|
91 size_t G1CardLiveData::live_card_bitmap_size_in_bits() const { |
|
92 return _max_capacity >> G1CardTable::card_shift; |
|
93 } |
|
94 |
|
95 // Helper class that provides functionality to generate the Live Data Count |
|
96 // information. |
|
97 class G1CardLiveDataHelper { |
|
98 private: |
|
99 BitMapView _region_bm; |
|
100 BitMapView _card_bm; |
|
101 |
|
102 // The card number of the bottom of the G1 heap. |
|
103 // Used in biasing indices into accounting card bitmaps. |
|
104 BitMap::idx_t _heap_card_bias; |
|
105 |
|
106 // Utility routine to set an exclusive range of bits on the given |
|
107 // bitmap, optimized for very small ranges. |
|
108 // There must be at least one bit to set. |
|
109 void set_card_bitmap_range(BitMap::idx_t start_idx, |
|
110 BitMap::idx_t end_idx) { |
|
111 |
|
112 // Set the exclusive bit range [start_idx, end_idx). |
|
113 assert((end_idx - start_idx) > 0, "at least one bit"); |
|
114 |
|
115 // For small ranges use a simple loop; otherwise use set_range. |
|
116 // The range is made up of the cards that are spanned by an object/mem |
|
117 // region so 8 cards will allow up to object sizes up to 4K to be handled |
|
118 // using the loop. |
|
119 if ((end_idx - start_idx) <= 8) { |
|
120 for (BitMap::idx_t i = start_idx; i < end_idx; i += 1) { |
|
121 _card_bm.set_bit(i); |
|
122 } |
|
123 } else { |
|
124 _card_bm.set_range(start_idx, end_idx); |
|
125 } |
|
126 } |
|
127 |
|
128 // We cache the last mark set. This avoids setting the same bit multiple times. |
|
129 // This is particularly interesting for dense bitmaps, as this avoids doing |
|
130 // lots of work most of the time. |
|
131 BitMap::idx_t _last_marked_bit_idx; |
|
132 |
|
133 void clear_card_bitmap_range(HeapWord* start, HeapWord* end) { |
|
134 BitMap::idx_t start_idx = card_live_bitmap_index_for(start); |
|
135 BitMap::idx_t end_idx = card_live_bitmap_index_for(align_up(end, CardTable::card_size)); |
|
136 |
|
137 _card_bm.clear_range(start_idx, end_idx); |
|
138 } |
|
139 |
|
140 // Mark the card liveness bitmap for the object spanning from start to end. |
|
141 void mark_card_bitmap_range(HeapWord* start, HeapWord* end) { |
|
142 BitMap::idx_t start_idx = card_live_bitmap_index_for(start); |
|
143 BitMap::idx_t end_idx = card_live_bitmap_index_for(align_up(end, CardTable::card_size)); |
|
144 |
|
145 assert((end_idx - start_idx) > 0, "Trying to mark zero sized range."); |
|
146 |
|
147 if (start_idx == _last_marked_bit_idx) { |
|
148 start_idx++; |
|
149 } |
|
150 if (start_idx == end_idx) { |
|
151 return; |
|
152 } |
|
153 |
|
154 // Set the bits in the card bitmap for the cards spanned by this object. |
|
155 set_card_bitmap_range(start_idx, end_idx); |
|
156 _last_marked_bit_idx = end_idx - 1; |
|
157 } |
|
158 |
|
159 void reset_mark_cache() { |
|
160 _last_marked_bit_idx = (BitMap::idx_t)-1; |
|
161 } |
|
162 |
|
163 public: |
|
164 // Returns the index in the per-card liveness count bitmap |
|
165 // for the given address |
|
166 inline BitMap::idx_t card_live_bitmap_index_for(HeapWord* addr) { |
|
167 // Below, the term "card num" means the result of shifting an address |
|
168 // by the card shift -- address 0 corresponds to card number 0. One |
|
169 // must subtract the card num of the bottom of the heap to obtain a |
|
170 // card table index. |
|
171 BitMap::idx_t card_num = uintptr_t(addr) >> G1CardTable::card_shift; |
|
172 return card_num - _heap_card_bias; |
|
173 } |
|
174 |
|
175 // Takes a region that's not empty (i.e., it has at least one |
|
176 // live object in it and sets its corresponding bit on the region |
|
177 // bitmap to 1. |
|
178 void set_bit_for_region(HeapRegion* hr) { |
|
179 _region_bm.par_set_bit(hr->hrm_index()); |
|
180 } |
|
181 |
|
182 void reset_live_data(HeapRegion* hr) { |
|
183 clear_card_bitmap_range(hr->next_top_at_mark_start(), hr->end()); |
|
184 } |
|
185 |
|
186 // Mark the range of bits covered by allocations done since the last marking |
|
187 // in the given heap region, i.e. from NTAMS to top of the given region. |
|
188 // Returns if there has been some allocation in this region since the last marking. |
|
189 bool mark_allocated_since_marking(HeapRegion* hr) { |
|
190 reset_mark_cache(); |
|
191 |
|
192 HeapWord* ntams = hr->next_top_at_mark_start(); |
|
193 HeapWord* top = hr->top(); |
|
194 |
|
195 assert(hr->bottom() <= ntams && ntams <= hr->end(), "Preconditions."); |
|
196 |
|
197 // Mark the allocated-since-marking portion... |
|
198 if (ntams < top) { |
|
199 mark_card_bitmap_range(ntams, top); |
|
200 return true; |
|
201 } else { |
|
202 return false; |
|
203 } |
|
204 } |
|
205 |
|
206 // Mark the range of bits covered by live objects on the mark bitmap between |
|
207 // bottom and NTAMS of the given region. |
|
208 // Returns the number of live bytes marked within that area for the given |
|
209 // heap region. |
|
210 size_t mark_marked_during_marking(G1CMBitMap* mark_bitmap, HeapRegion* hr) { |
|
211 reset_mark_cache(); |
|
212 |
|
213 size_t marked_bytes = 0; |
|
214 |
|
215 HeapWord* ntams = hr->next_top_at_mark_start(); |
|
216 HeapWord* start = hr->bottom(); |
|
217 |
|
218 if (ntams <= start) { |
|
219 // Skip empty regions. |
|
220 return 0; |
|
221 } |
|
222 if (hr->is_humongous()) { |
|
223 HeapRegion* start_region = hr->humongous_start_region(); |
|
224 if (mark_bitmap->is_marked(start_region->bottom())) { |
|
225 mark_card_bitmap_range(start, hr->top()); |
|
226 return pointer_delta(hr->top(), start, 1); |
|
227 } else { |
|
228 // Humongous start object was actually dead. |
|
229 return 0; |
|
230 } |
|
231 } |
|
232 |
|
233 assert(start <= hr->end() && start <= ntams && ntams <= hr->end(), |
|
234 "Preconditions not met - " |
|
235 "start: " PTR_FORMAT ", ntams: " PTR_FORMAT ", end: " PTR_FORMAT, |
|
236 p2i(start), p2i(ntams), p2i(hr->end())); |
|
237 |
|
238 // Find the first marked object at or after "start". |
|
239 start = mark_bitmap->get_next_marked_addr(start, ntams); |
|
240 while (start < ntams) { |
|
241 oop obj = oop(start); |
|
242 size_t obj_size = obj->size(); |
|
243 HeapWord* obj_end = start + obj_size; |
|
244 |
|
245 assert(obj_end <= hr->end(), "Humongous objects must have been handled elsewhere."); |
|
246 |
|
247 mark_card_bitmap_range(start, obj_end); |
|
248 |
|
249 // Add the size of this object to the number of marked bytes. |
|
250 marked_bytes += obj_size * HeapWordSize; |
|
251 |
|
252 // Find the next marked object after this one. |
|
253 start = mark_bitmap->get_next_marked_addr(obj_end, ntams); |
|
254 } |
|
255 |
|
256 return marked_bytes; |
|
257 } |
|
258 |
|
259 G1CardLiveDataHelper(G1CardLiveData* live_data, HeapWord* base_address) : |
|
260 _region_bm(live_data->live_regions_bm()), |
|
261 _card_bm(live_data->live_cards_bm()) { |
|
262 // Calculate the card number for the bottom of the heap. Used |
|
263 // in biasing indexes into the accounting card bitmaps. |
|
264 _heap_card_bias = |
|
265 uintptr_t(base_address) >> G1CardTable::card_shift; |
|
266 } |
|
267 }; |
|
268 |
|
269 class G1CreateCardLiveDataTask: public AbstractGangTask { |
|
270 // Aggregate the counting data that was constructed concurrently |
|
271 // with marking. |
|
272 class G1CreateLiveDataClosure : public HeapRegionClosure { |
|
273 G1CardLiveDataHelper _helper; |
|
274 |
|
275 G1CMBitMap* _mark_bitmap; |
|
276 |
|
277 G1ConcurrentMark* _cm; |
|
278 public: |
|
279 G1CreateLiveDataClosure(G1CollectedHeap* g1h, |
|
280 G1ConcurrentMark* cm, |
|
281 G1CMBitMap* mark_bitmap, |
|
282 G1CardLiveData* live_data) : |
|
283 HeapRegionClosure(), |
|
284 _helper(live_data, g1h->reserved_region().start()), |
|
285 _mark_bitmap(mark_bitmap), |
|
286 _cm(cm) { } |
|
287 |
|
288 bool do_heap_region(HeapRegion* hr) { |
|
289 size_t marked_bytes = _helper.mark_marked_during_marking(_mark_bitmap, hr); |
|
290 if (marked_bytes > 0) { |
|
291 hr->add_to_marked_bytes(marked_bytes); |
|
292 } |
|
293 |
|
294 return (_cm->do_yield_check() && _cm->has_aborted()); |
|
295 } |
|
296 }; |
|
297 |
|
298 G1ConcurrentMark* _cm; |
|
299 G1CardLiveData* _live_data; |
|
300 HeapRegionClaimer _hr_claimer; |
|
301 |
|
302 public: |
|
303 G1CreateCardLiveDataTask(G1CMBitMap* bitmap, |
|
304 G1CardLiveData* live_data, |
|
305 uint n_workers) : |
|
306 AbstractGangTask("G1 Create Live Data"), |
|
307 _live_data(live_data), |
|
308 _hr_claimer(n_workers) { |
|
309 } |
|
310 |
|
311 void work(uint worker_id) { |
|
312 SuspendibleThreadSetJoiner sts_join; |
|
313 |
|
314 G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
|
315 G1ConcurrentMark* cm = g1h->concurrent_mark(); |
|
316 G1CreateLiveDataClosure cl(g1h, cm, cm->next_mark_bitmap(), _live_data); |
|
317 g1h->heap_region_par_iterate_from_worker_offset(&cl, &_hr_claimer, worker_id); |
|
318 } |
|
319 }; |
|
320 |
|
321 void G1CardLiveData::create(WorkGang* workers, G1CMBitMap* mark_bitmap) { |
|
322 _gc_timestamp_at_create = G1CollectedHeap::heap()->get_gc_time_stamp(); |
|
323 |
|
324 uint n_workers = workers->active_workers(); |
|
325 |
|
326 G1CreateCardLiveDataTask cl(mark_bitmap, |
|
327 this, |
|
328 n_workers); |
|
329 workers->run_task(&cl); |
|
330 } |
|
331 |
|
332 class G1FinalizeCardLiveDataTask: public AbstractGangTask { |
|
333 // Finalizes the liveness counting data. |
|
334 // Sets the bits corresponding to the interval [NTAMS, top] |
|
335 // (which contains the implicitly live objects) in the |
|
336 // card liveness bitmap. Also sets the bit for each region |
|
337 // containing live data, in the region liveness bitmap. |
|
338 class G1FinalizeCardLiveDataClosure: public HeapRegionClosure { |
|
339 private: |
|
340 G1CardLiveDataHelper _helper; |
|
341 |
|
342 uint _gc_timestamp_at_create; |
|
343 |
|
344 bool has_been_reclaimed(HeapRegion* hr) const { |
|
345 return hr->get_gc_time_stamp() > _gc_timestamp_at_create; |
|
346 } |
|
347 public: |
|
348 G1FinalizeCardLiveDataClosure(G1CollectedHeap* g1h, |
|
349 G1CMBitMap* bitmap, |
|
350 G1CardLiveData* live_data) : |
|
351 HeapRegionClosure(), |
|
352 _helper(live_data, g1h->reserved_region().start()), |
|
353 _gc_timestamp_at_create(live_data->gc_timestamp_at_create()) { } |
|
354 |
|
355 bool do_heap_region(HeapRegion* hr) { |
|
356 if (has_been_reclaimed(hr)) { |
|
357 _helper.reset_live_data(hr); |
|
358 } |
|
359 bool allocated_since_marking = _helper.mark_allocated_since_marking(hr); |
|
360 if (allocated_since_marking || hr->next_marked_bytes() > 0) { |
|
361 _helper.set_bit_for_region(hr); |
|
362 } |
|
363 return false; |
|
364 } |
|
365 }; |
|
366 |
|
367 G1CMBitMap* _bitmap; |
|
368 |
|
369 G1CardLiveData* _live_data; |
|
370 |
|
371 HeapRegionClaimer _hr_claimer; |
|
372 |
|
373 public: |
|
374 G1FinalizeCardLiveDataTask(G1CMBitMap* bitmap, G1CardLiveData* live_data, uint n_workers) : |
|
375 AbstractGangTask("G1 Finalize Card Live Data"), |
|
376 _bitmap(bitmap), |
|
377 _live_data(live_data), |
|
378 _hr_claimer(n_workers) { |
|
379 } |
|
380 |
|
381 void work(uint worker_id) { |
|
382 G1FinalizeCardLiveDataClosure cl(G1CollectedHeap::heap(), _bitmap, _live_data); |
|
383 |
|
384 G1CollectedHeap::heap()->heap_region_par_iterate_from_worker_offset(&cl, &_hr_claimer, worker_id); |
|
385 } |
|
386 }; |
|
387 |
|
388 void G1CardLiveData::finalize(WorkGang* workers, G1CMBitMap* mark_bitmap) { |
|
389 // Finalize the live data. |
|
390 G1FinalizeCardLiveDataTask cl(mark_bitmap, |
|
391 this, |
|
392 workers->active_workers()); |
|
393 workers->run_task(&cl); |
|
394 } |
|
395 |
|
396 class G1ClearCardLiveDataTask : public AbstractGangTask { |
|
397 BitMapView _bitmap; |
|
398 size_t _num_chunks; |
|
399 size_t _cur_chunk; |
|
400 public: |
|
401 G1ClearCardLiveDataTask(const BitMapView& bitmap, size_t num_tasks) : |
|
402 AbstractGangTask("G1 Clear Card Live Data"), |
|
403 _bitmap(bitmap), |
|
404 _num_chunks(num_tasks), |
|
405 _cur_chunk(0) { |
|
406 } |
|
407 |
|
408 static size_t chunk_size() { return M; } |
|
409 |
|
410 virtual void work(uint worker_id) { |
|
411 while (true) { |
|
412 size_t to_process = Atomic::add(1u, &_cur_chunk) - 1; |
|
413 if (to_process >= _num_chunks) { |
|
414 break; |
|
415 } |
|
416 |
|
417 BitMap::idx_t start = M * BitsPerByte * to_process; |
|
418 BitMap::idx_t end = MIN2(start + M * BitsPerByte, _bitmap.size()); |
|
419 _bitmap.clear_range(start, end); |
|
420 } |
|
421 } |
|
422 }; |
|
423 |
|
424 void G1CardLiveData::clear(WorkGang* workers) { |
|
425 guarantee(Universe::is_fully_initialized(), "Should not call this during initialization."); |
|
426 |
|
427 size_t const num_chunks = align_up(live_cards_bm().size_in_bytes(), G1ClearCardLiveDataTask::chunk_size()) / G1ClearCardLiveDataTask::chunk_size(); |
|
428 uint const num_workers = (uint)MIN2(num_chunks, (size_t)workers->active_workers()); |
|
429 |
|
430 G1ClearCardLiveDataTask cl(live_cards_bm(), num_chunks); |
|
431 |
|
432 log_debug(gc, ergo)("Running %s using %u workers for " SIZE_FORMAT " work units.", cl.name(), num_workers, num_chunks); |
|
433 workers->run_task(&cl, num_workers); |
|
434 |
|
435 // The region live bitmap is always very small, even for huge heaps. Clear |
|
436 // directly. |
|
437 live_regions_bm().clear(); |
|
438 } |
|
439 |
|
440 class G1VerifyCardLiveDataTask: public AbstractGangTask { |
|
441 // Heap region closure used for verifying the live count data |
|
442 // that was created concurrently and finalized during |
|
443 // the remark pause. This closure is applied to the heap |
|
444 // regions during the STW cleanup pause. |
|
445 class G1VerifyCardLiveDataClosure: public HeapRegionClosure { |
|
446 private: |
|
447 G1CollectedHeap* _g1h; |
|
448 G1CMBitMap* _mark_bitmap; |
|
449 G1CardLiveDataHelper _helper; |
|
450 |
|
451 G1CardLiveData* _act_live_data; |
|
452 |
|
453 G1CardLiveData* _exp_live_data; |
|
454 |
|
455 int _failures; |
|
456 |
|
457 // Completely recreates the live data count for the given heap region and |
|
458 // returns the number of bytes marked. |
|
459 size_t create_live_data_count(HeapRegion* hr) { |
|
460 size_t bytes_marked = _helper.mark_marked_during_marking(_mark_bitmap, hr); |
|
461 bool allocated_since_marking = _helper.mark_allocated_since_marking(hr); |
|
462 if (allocated_since_marking || bytes_marked > 0) { |
|
463 _helper.set_bit_for_region(hr); |
|
464 } |
|
465 return bytes_marked; |
|
466 } |
|
467 public: |
|
468 G1VerifyCardLiveDataClosure(G1CollectedHeap* g1h, |
|
469 G1CMBitMap* mark_bitmap, |
|
470 G1CardLiveData* act_live_data, |
|
471 G1CardLiveData* exp_live_data) : |
|
472 _g1h(g1h), |
|
473 _mark_bitmap(mark_bitmap), |
|
474 _helper(exp_live_data, g1h->reserved_region().start()), |
|
475 _act_live_data(act_live_data), |
|
476 _exp_live_data(exp_live_data), |
|
477 _failures(0) { } |
|
478 |
|
479 int failures() const { return _failures; } |
|
480 |
|
481 bool do_heap_region(HeapRegion* hr) { |
|
482 int failures = 0; |
|
483 |
|
484 // Walk the marking bitmap for this region and set the corresponding bits |
|
485 // in the expected region and card bitmaps. |
|
486 size_t exp_marked_bytes = create_live_data_count(hr); |
|
487 size_t act_marked_bytes = hr->next_marked_bytes(); |
|
488 // Verify the marked bytes for this region. |
|
489 |
|
490 if (exp_marked_bytes != act_marked_bytes) { |
|
491 log_error(gc)("Expected marked bytes " SIZE_FORMAT " != actual marked bytes " SIZE_FORMAT " in region %u", exp_marked_bytes, act_marked_bytes, hr->hrm_index()); |
|
492 failures += 1; |
|
493 } else if (exp_marked_bytes > HeapRegion::GrainBytes) { |
|
494 log_error(gc)("Expected marked bytes " SIZE_FORMAT " larger than possible " SIZE_FORMAT " in region %u", exp_marked_bytes, HeapRegion::GrainBytes, hr->hrm_index()); |
|
495 failures += 1; |
|
496 } |
|
497 |
|
498 // Verify the bit, for this region, in the actual and expected |
|
499 // (which was just calculated) region bit maps. |
|
500 uint index = hr->hrm_index(); |
|
501 |
|
502 bool expected = _exp_live_data->is_region_live(index); |
|
503 bool actual = _act_live_data->is_region_live(index); |
|
504 if (expected != actual) { |
|
505 log_error(gc)("Expected liveness %d not equal actual %d in region %u", expected, actual, hr->hrm_index()); |
|
506 failures += 1; |
|
507 } |
|
508 |
|
509 // Verify that the card bit maps for the cards spanned by the current |
|
510 // region match. |
|
511 BitMap::idx_t start_idx = _helper.card_live_bitmap_index_for(hr->bottom()); |
|
512 BitMap::idx_t end_idx = _helper.card_live_bitmap_index_for(hr->top()); |
|
513 |
|
514 for (BitMap::idx_t i = start_idx; i < end_idx; i+=1) { |
|
515 expected = _exp_live_data->is_card_live_at(i); |
|
516 actual = _act_live_data->is_card_live_at(i); |
|
517 |
|
518 if (expected != actual) { |
|
519 log_error(gc)("Expected card liveness %d not equal actual card liveness %d at card " SIZE_FORMAT " in region %u", expected, actual, i, hr->hrm_index()); |
|
520 failures += 1; |
|
521 } |
|
522 } |
|
523 |
|
524 _failures += failures; |
|
525 |
|
526 // We could stop iteration over the heap when we |
|
527 // find the first violating region by returning true. |
|
528 return false; |
|
529 } |
|
530 }; |
|
531 protected: |
|
532 G1CollectedHeap* _g1h; |
|
533 G1CMBitMap* _mark_bitmap; |
|
534 |
|
535 G1CardLiveData* _act_live_data; |
|
536 |
|
537 G1CardLiveData _exp_live_data; |
|
538 |
|
539 int _failures; |
|
540 |
|
541 HeapRegionClaimer _hr_claimer; |
|
542 |
|
543 public: |
|
544 G1VerifyCardLiveDataTask(G1CMBitMap* bitmap, |
|
545 G1CardLiveData* act_live_data, |
|
546 uint n_workers) |
|
547 : AbstractGangTask("G1 Verify Card Live Data"), |
|
548 _g1h(G1CollectedHeap::heap()), |
|
549 _mark_bitmap(bitmap), |
|
550 _act_live_data(act_live_data), |
|
551 _exp_live_data(), |
|
552 _failures(0), |
|
553 _hr_claimer(n_workers) { |
|
554 assert(VerifyDuringGC, "don't call this otherwise"); |
|
555 _exp_live_data.initialize(_g1h->max_capacity(), _g1h->max_regions()); |
|
556 } |
|
557 |
|
558 void work(uint worker_id) { |
|
559 G1VerifyCardLiveDataClosure cl(_g1h, |
|
560 _mark_bitmap, |
|
561 _act_live_data, |
|
562 &_exp_live_data); |
|
563 _g1h->heap_region_par_iterate_from_worker_offset(&cl, &_hr_claimer, worker_id); |
|
564 |
|
565 Atomic::add(cl.failures(), &_failures); |
|
566 } |
|
567 |
|
568 int failures() const { return _failures; } |
|
569 }; |
|
570 |
|
571 void G1CardLiveData::verify(WorkGang* workers, G1CMBitMap* actual_bitmap) { |
|
572 ResourceMark rm; |
|
573 |
|
574 G1VerifyCardLiveDataTask cl(actual_bitmap, |
|
575 this, |
|
576 workers->active_workers()); |
|
577 workers->run_task(&cl); |
|
578 |
|
579 guarantee(cl.failures() == 0, "Unexpected accounting failures"); |
|
580 } |
|
581 |
|
582 #ifndef PRODUCT |
|
583 void G1CardLiveData::verify_is_clear() { |
|
584 assert(live_cards_bm().count_one_bits() == 0, "Live cards bitmap must be clear."); |
|
585 assert(live_regions_bm().count_one_bits() == 0, "Live regions bitmap must be clear."); |
|
586 } |
|
587 #endif |
|