1 /*
2 * Copyright (c) 2014, 2015, 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.
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23 */
24
25 #ifndef SHARE_VM_GC_G1_G1PARSCANTHREADSTATE_HPP
26 #define SHARE_VM_GC_G1_G1PARSCANTHREADSTATE_HPP
27
28 #include "gc/g1/dirtyCardQueue.hpp"
29 #include "gc/g1/g1CollectedHeap.hpp"
30 #include "gc/g1/g1CollectorPolicy.hpp"
31 #include "gc/g1/g1OopClosures.hpp"
32 #include "gc/g1/g1RemSet.hpp"
33 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
34 #include "gc/shared/ageTable.hpp"
35 #include "memory/allocation.hpp"
36 #include "oops/oop.hpp"
37
38 class G1PLABAllocator;
39 class G1EvacuationRootClosures;
40 class HeapRegion;
41 class outputStream;
42
43 class G1ParScanThreadState : public CHeapObj<mtGC> {
44 private:
45 G1CollectedHeap* _g1h;
46 RefToScanQueue* _refs;
47 DirtyCardQueue _dcq;
48 G1SATBCardTableModRefBS* _ct_bs;
49 G1EvacuationRootClosures* _closures;
50
51 G1PLABAllocator* _plab_allocator;
52
53 ageTable _age_table;
54 InCSetState _dest[InCSetState::Num];
55 // Local tenuring threshold.
56 uint _tenuring_threshold;
57 G1ParScanClosure _scanner;
58
59 int _hash_seed;
60 uint _worker_id;
61
62 // Map from young-age-index (0 == not young, 1 is youngest) to
63 // surviving words. base is what we get back from the malloc call
64 size_t* _surviving_young_words_base;
65 // this points into the array, as we use the first few entries for padding
66 size_t* _surviving_young_words;
67
68 // Indicates whether in the last generation (old) there is no more space
69 // available for allocation.
70 bool _old_gen_is_full;
71
72 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
73
74 DirtyCardQueue& dirty_card_queue() { return _dcq; }
75 G1SATBCardTableModRefBS* ctbs() { return _ct_bs; }
76
77 InCSetState dest(InCSetState original) const {
78 assert(original.is_valid(),
79 "Original state invalid: " CSETSTATE_FORMAT, original.value());
80 assert(_dest[original.value()].is_valid_gen(),
81 "Dest state is invalid: " CSETSTATE_FORMAT, _dest[original.value()].value());
82 return _dest[original.value()];
83 }
84
85 public:
86 G1ParScanThreadState(G1CollectedHeap* g1h, uint worker_id, size_t young_cset_length);
87 virtual ~G1ParScanThreadState();
88
89 void set_ref_processor(ReferenceProcessor* rp) { _scanner.set_ref_processor(rp); }
90
91 #ifdef ASSERT
92 bool queue_is_empty() const { return _refs->is_empty(); }
93
94 bool verify_ref(narrowOop* ref) const;
95 bool verify_ref(oop* ref) const;
96 bool verify_task(StarTask ref) const;
97 #endif // ASSERT
98
99 template <class T> void push_on_queue(T* ref);
100
101 template <class T> void update_rs(HeapRegion* from, T* p, oop o) {
102 // If the new value of the field points to the same region or
103 // is the to-space, we don't need to include it in the Rset updates.
104 if (!HeapRegion::is_in_same_region(p, o) && !from->is_young()) {
105 size_t card_index = ctbs()->index_for(p);
106 // If the card hasn't been added to the buffer, do it.
107 if (ctbs()->mark_card_deferred(card_index)) {
108 dirty_card_queue().enqueue((jbyte*)ctbs()->byte_for_index(card_index));
109 }
110 }
111 }
112
113 G1EvacuationRootClosures* closures() { return _closures; }
114 uint worker_id() { return _worker_id; }
115
116 // Returns the current amount of waste due to alignment or not being able to fit
117 // objects within LABs and the undo waste.
118 virtual void waste(size_t& wasted, size_t& undo_wasted);
119
120 size_t* surviving_young_words() {
121 // We add one to hide entry 0 which accumulates surviving words for
122 // age -1 regions (i.e. non-young ones)
123 return _surviving_young_words + 1;
124 }
125
126 void flush(size_t* surviving_young_words);
127
128 private:
129 #define G1_PARTIAL_ARRAY_MASK 0x2
130
131 inline bool has_partial_array_mask(oop* ref) const {
132 return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
133 }
134
135 // We never encode partial array oops as narrowOop*, so return false immediately.
136 // This allows the compiler to create optimized code when popping references from
137 // the work queue.
138 inline bool has_partial_array_mask(narrowOop* ref) const {
139 assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
140 return false;
141 }
142
143 // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
144 // We always encode partial arrays as regular oop, to allow the
145 // specialization for has_partial_array_mask() for narrowOops above.
146 // This means that unintentional use of this method with narrowOops are caught
147 // by the compiler.
148 inline oop* set_partial_array_mask(oop obj) const {
149 assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
150 return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
151 }
152
153 inline oop clear_partial_array_mask(oop* ref) const {
154 return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
155 }
156
157 inline void do_oop_partial_array(oop* p);
158
159 // This method is applied to the fields of the objects that have just been copied.
160 template <class T> inline void do_oop_evac(T* p, HeapRegion* from);
161
162 template <class T> inline void deal_with_reference(T* ref_to_scan);
163
164 inline void dispatch_reference(StarTask ref);
165
166 // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
167 // allocate into dest. State is the original (source) cset state for the object
168 // that is allocated for. Previous_plab_refill_failed indicates whether previously
169 // a PLAB refill into "state" failed.
170 // Returns a non-NULL pointer if successful, and updates dest if required.
171 // Also determines whether we should continue to try to allocate into the various
172 // generations or just end trying to allocate.
173 HeapWord* allocate_in_next_plab(InCSetState const state,
174 InCSetState* dest,
175 size_t word_sz,
176 AllocationContext_t const context,
177 bool previous_plab_refill_failed);
178
179 inline InCSetState next_state(InCSetState const state, markOop const m, uint& age);
180
181 void report_promotion_event(InCSetState const dest_state,
182 oop const old, size_t word_sz, uint age,
183 HeapWord * const obj_ptr, const AllocationContext_t context) const;
184 public:
185
186 oop copy_to_survivor_space(InCSetState const state, oop const obj, markOop const old_mark);
187
188 void trim_queue();
189
190 inline void steal_and_trim_queue(RefToScanQueueSet *task_queues);
191
192 // An attempt to evacuate "obj" has failed; take necessary steps.
193 oop handle_evacuation_failure_par(oop obj, markOop m);
194 };
195
196 class G1ParScanThreadStateSet : public StackObj {
197 G1CollectedHeap* _g1h;
198 G1ParScanThreadState** _states;
199 size_t* _surviving_young_words_total;
200 size_t* _cards_scanned;
201 size_t _total_cards_scanned;
202 uint _n_workers;
203 bool _flushed;
204
205 public:
206 G1ParScanThreadStateSet(G1CollectedHeap* g1h, uint n_workers, size_t young_cset_length) :
207 _g1h(g1h),
208 _states(NEW_C_HEAP_ARRAY(G1ParScanThreadState*, n_workers, mtGC)),
209 _surviving_young_words_total(NEW_C_HEAP_ARRAY(size_t, young_cset_length, mtGC)),
210 _cards_scanned(NEW_C_HEAP_ARRAY(size_t, n_workers, mtGC)),
211 _total_cards_scanned(0),
212 _n_workers(n_workers),
213 _flushed(false) {
214 for (uint i = 0; i < n_workers; ++i) {
215 _states[i] = new_par_scan_state(i, young_cset_length);
216 }
217 memset(_surviving_young_words_total, 0, young_cset_length * sizeof(size_t));
218 memset(_cards_scanned, 0, n_workers * sizeof(size_t));
219 }
220
221 ~G1ParScanThreadStateSet() {
222 assert(_flushed, "thread local state from the per thread states should have been flushed");
223 FREE_C_HEAP_ARRAY(G1ParScanThreadState*, _states);
224 FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_total);
225 FREE_C_HEAP_ARRAY(size_t, _cards_scanned);
226 }
227
228 void flush();
229
230 G1ParScanThreadState* state_for_worker(uint worker_id);
231
232 void add_cards_scanned(uint worker_id, size_t cards_scanned);
233 size_t total_cards_scanned() const;
234 const size_t* surviving_young_words() const;
235
236 private:
237 G1ParScanThreadState* new_par_scan_state(uint worker_id, size_t young_cset_length);
238 };
239
240 #endif // SHARE_VM_GC_G1_G1PARSCANTHREADSTATE_HPP