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.
22 *
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 HeapRegion;
39 class outputStream;
40
41 class G1ParScanThreadState : public CHeapObj<mtGC> {
42 private:
43 G1CollectedHeap* _g1h;
44 RefToScanQueue* _refs;
45 DirtyCardQueue _dcq;
46 G1SATBCardTableModRefBS* _ct_bs;
47 G1RemSet* _g1_rem;
48
49 G1PLABAllocator* _plab_allocator;
50
51 ageTable _age_table;
52 InCSetState _dest[InCSetState::Num];
53 // Local tenuring threshold.
54 uint _tenuring_threshold;
55 G1ParScanClosure _scanner;
56
57 int _hash_seed;
58 uint _worker_id;
59
60 // Map from young-age-index (0 == not young, 1 is youngest) to
61 // surviving words. base is what we get back from the malloc call
62 size_t* _surviving_young_words_base;
63 // this points into the array, as we use the first few entries for padding
64 size_t* _surviving_young_words;
65
66 // Indicates whether in the last generation (old) there is no more space
67 // available for allocation.
68 bool _old_gen_is_full;
69
70 #define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t))
71
72 DirtyCardQueue& dirty_card_queue() { return _dcq; }
73 G1SATBCardTableModRefBS* ctbs() { return _ct_bs; }
74
75 InCSetState dest(InCSetState original) const {
76 assert(original.is_valid(),
77 err_msg("Original state invalid: " CSETSTATE_FORMAT, original.value()));
78 assert(_dest[original.value()].is_valid_gen(),
79 err_msg("Dest state is invalid: " CSETSTATE_FORMAT, _dest[original.value()].value()));
80 return _dest[original.value()];
81 }
82
83 public:
84 G1ParScanThreadState(G1CollectedHeap* g1h, uint worker_id);
85 ~G1ParScanThreadState();
86
87 void set_ref_processor(ReferenceProcessor* rp) { _scanner.set_ref_processor(rp); }
88
89 ageTable* age_table() { return &_age_table; }
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, uint tid) {
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 (!from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) && !from->is_survivor()) {
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 uint worker_id() { return _worker_id; }
114
115 // Returns the current amount of waste due to alignment or not being able to fit
116 // objects within LABs and the undo waste.
117 virtual void waste(size_t& wasted, size_t& undo_wasted);
118
119 size_t* surviving_young_words() {
120 // We add one to hide entry 0 which accumulates surviving words for
121 // age -1 regions (i.e. non-young ones)
122 return _surviving_young_words + 1;
123 }
124
125 private:
126 #define G1_PARTIAL_ARRAY_MASK 0x2
127
128 inline bool has_partial_array_mask(oop* ref) const {
129 return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
130 }
131
132 // We never encode partial array oops as narrowOop*, so return false immediately.
133 // This allows the compiler to create optimized code when popping references from
134 // the work queue.
135 inline bool has_partial_array_mask(narrowOop* ref) const {
136 assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
137 return false;
138 }
139
140 // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
141 // We always encode partial arrays as regular oop, to allow the
142 // specialization for has_partial_array_mask() for narrowOops above.
143 // This means that unintentional use of this method with narrowOops are caught
144 // by the compiler.
145 inline oop* set_partial_array_mask(oop obj) const {
146 assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
147 return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
148 }
149
150 inline oop clear_partial_array_mask(oop* ref) const {
151 return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
152 }
153
154 inline void do_oop_partial_array(oop* p);
155
156 // This method is applied to the fields of the objects that have just been copied.
157 template <class T> inline void do_oop_evac(T* p, HeapRegion* from);
158
159 template <class T> inline void deal_with_reference(T* ref_to_scan);
160
161 inline void dispatch_reference(StarTask ref);
162
163 // Tries to allocate word_sz in the PLAB of the next "generation" after trying to
164 // allocate into dest. State is the original (source) cset state for the object
165 // that is allocated for. Previous_plab_refill_failed indicates whether previously
166 // a PLAB refill into "state" failed.
167 // Returns a non-NULL pointer if successful, and updates dest if required.
168 // Also determines whether we should continue to try to allocate into the various
169 // generations or just end trying to allocate.
170 HeapWord* allocate_in_next_plab(InCSetState const state,
171 InCSetState* dest,
172 size_t word_sz,
173 AllocationContext_t const context,
174 bool previous_plab_refill_failed);
175
176 inline InCSetState next_state(InCSetState const state, markOop const m, uint& age);
177 public:
178
179 oop copy_to_survivor_space(InCSetState const state, oop const obj, markOop const old_mark);
180
181 void trim_queue();
182
183 inline void steal_and_trim_queue(RefToScanQueueSet *task_queues);
184
185 // An attempt to evacuate "obj" has failed; take necessary steps.
186 oop handle_evacuation_failure_par(oop obj, markOop m);
187 };
188
189 #endif // SHARE_VM_GC_G1_G1PARSCANTHREADSTATE_HPP