1 /*
2 * Copyright (c) 2014, 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.
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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/g1CardTable.hpp"
30 #include "gc/g1/g1CollectedHeap.hpp"
31 #include "gc/g1/g1OopClosures.hpp"
32 #include "gc/g1/g1Policy.hpp"
33 #include "gc/g1/g1RemSet.hpp"
34 #include "gc/g1/heapRegionRemSet.hpp"
35 #include "gc/shared/ageTable.hpp"
36 #include "memory/allocation.hpp"
37 #include "oops/oop.hpp"
38
39 class G1PLABAllocator;
40 class G1EvacuationRootClosures;
41 class HeapRegion;
42 class outputStream;
43
44 class G1ParScanThreadState : public CHeapObj<mtGC> {
45 private:
46 G1CollectedHeap* _g1h;
47 RefToScanQueue* _refs;
48 DirtyCardQueue _dcq;
49 G1CardTable* _ct;
50 G1EvacuationRootClosures* _closures;
51
52 G1PLABAllocator* _plab_allocator;
53
54 AgeTable _age_table;
55 InCSetState _dest[InCSetState::Num];
56 // Local tenuring threshold.
57 uint _tenuring_threshold;
58 G1ScanEvacuatedObjClosure _scanner;
59
60 int _hash_seed;
61 uint _worker_id;
62
63 // Map from young-age-index (0 == not young, 1 is youngest) to
64 // surviving words. base is what we get back from the malloc call
65 size_t* _surviving_young_words_base;
66 // this points into the array, as we use the first few entries for padding
67 size_t* _surviving_young_words;
68
69 // Indicates whether in the last generation (old) there is no more space
70 // available for allocation.
71 bool _old_gen_is_full;
72
73 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
74
75 DirtyCardQueue& dirty_card_queue() { return _dcq; }
76 G1CardTable* ct() { return _ct; }
77
78 InCSetState dest(InCSetState original) const {
79 assert(original.is_valid(),
80 "Original state invalid: " CSETSTATE_FORMAT, original.value());
81 assert(_dest[original.value()].is_valid_gen(),
82 "Dest state is invalid: " CSETSTATE_FORMAT, _dest[original.value()].value());
83 return _dest[original.value()];
84 }
85
86 public:
87 G1ParScanThreadState(G1CollectedHeap* g1h, uint worker_id, size_t young_cset_length);
88 virtual ~G1ParScanThreadState();
89
90 void set_ref_discoverer(ReferenceDiscoverer* rd) { _scanner.set_ref_discoverer(rd); }
91
92 #ifdef ASSERT
93 bool queue_is_empty() const { return _refs->is_empty(); }
94
95 bool verify_ref(narrowOop* ref) const;
96 bool verify_ref(oop* ref) const;
97 bool verify_task(StarTask ref) const;
98 #endif // ASSERT
99
100 template <class T> void do_oop_ext(T* ref);
101 template <class T> void push_on_queue(T* ref);
102
103 template <class T> void update_rs(HeapRegion* from, T* p, oop o) {
104 assert(!HeapRegion::is_in_same_region(p, o), "Caller should have filtered out cross-region references already.");
105 // If the field originates from the to-space, we don't need to include it
106 // in the remembered set updates. Also, if we are not tracking the remembered
107 // set in the destination region, do not bother either.
108 if (!from->is_young() && _g1h->heap_region_containing((HeapWord*)o)->rem_set()->is_tracked()) {
109 size_t card_index = ct()->index_for(p);
110 // If the card hasn't been added to the buffer, do it.
111 if (ct()->mark_card_deferred(card_index)) {
112 dirty_card_queue().enqueue((jbyte*)ct()->byte_for_index(card_index));
113 }
114 }
115 }
116
117 G1EvacuationRootClosures* closures() { return _closures; }
118 uint worker_id() { return _worker_id; }
119
120 // Returns the current amount of waste due to alignment or not being able to fit
121 // objects within LABs and the undo waste.
122 virtual void waste(size_t& wasted, size_t& undo_wasted);
123
124 size_t* surviving_young_words() {
125 // We add one to hide entry 0 which accumulates surviving words for
126 // age -1 regions (i.e. non-young ones)
127 return _surviving_young_words + 1;
128 }
129
130 void flush(size_t* surviving_young_words);
131
132 private:
133 #define G1_PARTIAL_ARRAY_MASK 0x2
134
135 inline bool has_partial_array_mask(oop* ref) const {
136 return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
137 }
138
139 // We never encode partial array oops as narrowOop*, so return false immediately.
140 // This allows the compiler to create optimized code when popping references from
141 // the work queue.
142 inline bool has_partial_array_mask(narrowOop* ref) const {
143 assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
144 return false;
145 }
146
147 // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
148 // We always encode partial arrays as regular oop, to allow the
149 // specialization for has_partial_array_mask() for narrowOops above.
150 // This means that unintentional use of this method with narrowOops are caught
151 // by the compiler.
152 inline oop* set_partial_array_mask(oop obj) const {
153 assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
154 return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
155 }
156
157 inline oop clear_partial_array_mask(oop* ref) const {
158 return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
159 }
160
161 inline void do_oop_partial_array(oop* p);
162
163 // This method is applied to the fields of the objects that have just been copied.
164 template <class T> inline void do_oop_evac(T* p, HeapRegion* from);
165
166 template <class T> inline void deal_with_reference(T* ref_to_scan);
167
168 inline void dispatch_reference(StarTask ref);
169
170 // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
171 // allocate into dest. State is the original (source) cset state for the object
172 // that is allocated for. Previous_plab_refill_failed indicates whether previously
173 // a PLAB refill into "state" failed.
174 // Returns a non-NULL pointer if successful, and updates dest if required.
175 // Also determines whether we should continue to try to allocate into the various
176 // generations or just end trying to allocate.
177 HeapWord* allocate_in_next_plab(InCSetState const state,
178 InCSetState* dest,
179 size_t word_sz,
180 bool previous_plab_refill_failed);
181
182 inline InCSetState next_state(InCSetState const state, markOop const m, uint& age);
183
184 void report_promotion_event(InCSetState const dest_state,
185 oop const old, size_t word_sz, uint age,
186 HeapWord * const obj_ptr) const;
187 public:
188
189 oop copy_to_survivor_space(InCSetState const state, oop const obj, markOop const old_mark);
190
191 void trim_queue();
192
193 inline void steal_and_trim_queue(RefToScanQueueSet *task_queues);
194
195 // An attempt to evacuate "obj" has failed; take necessary steps.
196 oop handle_evacuation_failure_par(oop obj, markOop m);
197 };
198
199 class G1ParScanThreadStateSet : public StackObj {
200 G1CollectedHeap* _g1h;
201 G1ParScanThreadState** _states;
202 size_t* _surviving_young_words_total;
203 size_t _young_cset_length;
204 uint _n_workers;
205 bool _flushed;
206
207 public:
208 G1ParScanThreadStateSet(G1CollectedHeap* g1h, uint n_workers, size_t young_cset_length);
209 ~G1ParScanThreadStateSet();
210
211 void flush();
212
213 G1ParScanThreadState* state_for_worker(uint worker_id);
214
215 const size_t* surviving_young_words() const;
216
217 private:
218 G1ParScanThreadState* new_par_scan_state(uint worker_id, size_t young_cset_length);
219 };
220
221 #endif // SHARE_VM_GC_G1_G1PARSCANTHREADSTATE_HPP