1 /*
2 * Copyright (c) 2001, 2012, 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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_DIRTYCARDQUEUE_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_DIRTYCARDQUEUE_HPP
27
28 #include "gc_implementation/g1/ptrQueue.hpp"
29 #include "memory/allocation.hpp"
30
31 class FreeIdSet;
32
33 // A closure class for processing card table entries. Note that we don't
34 // require these closure objects to be stack-allocated.
35 class CardTableEntryClosure: public CHeapObj<mtGC> {
36 public:
37 // Process the card whose card table entry is "card_ptr". If returns
38 // "false", terminate the iteration early.
39 virtual bool do_card_ptr(jbyte* card_ptr, uint worker_i = 0) = 0;
40 };
41
42 // A ptrQueue whose elements are "oops", pointers to object heads.
43 class DirtyCardQueue: public PtrQueue {
44 public:
45 DirtyCardQueue(PtrQueueSet* qset_, bool perm = false) :
46 // Dirty card queues are always active, so we create them with their
47 // active field set to true.
48 PtrQueue(qset_, perm, true /* active */) { }
49
50 // Apply the closure to all elements, and reset the index to make the
51 // buffer empty. If a closure application returns "false", return
52 // "false" immediately, halting the iteration. If "consume" is true,
53 // deletes processed entries from logs.
54 bool apply_closure(CardTableEntryClosure* cl,
55 bool consume = true,
56 uint worker_i = 0);
57
58 // Apply the closure to all elements of "buf", down to "index"
59 // (inclusive.) If returns "false", then a closure application returned
60 // "false", and we return immediately. If "consume" is true, entries are
61 // set to NULL as they are processed, so they will not be processed again
62 // later.
63 static bool apply_closure_to_buffer(CardTableEntryClosure* cl,
64 void** buf, size_t index, size_t sz,
65 bool consume = true,
66 uint worker_i = 0);
67 void **get_buf() { return _buf;}
68 void set_buf(void **buf) {_buf = buf;}
69 size_t get_index() { return _index;}
70 void reinitialize() { _buf = 0; _sz = 0; _index = 0;}
71 };
72
73
74
75 class DirtyCardQueueSet: public PtrQueueSet {
76 CardTableEntryClosure* _closure;
77
78 DirtyCardQueue _shared_dirty_card_queue;
79
80 // Override.
81 bool mut_process_buffer(void** buf);
82
83 // Protected by the _cbl_mon.
84 FreeIdSet* _free_ids;
85
86 // The number of completed buffers processed by mutator and rs thread,
87 // respectively.
88 jint _processed_buffers_mut;
89 jint _processed_buffers_rs_thread;
90
91 public:
92 DirtyCardQueueSet(bool notify_when_complete = true);
93
94 void initialize(Monitor* cbl_mon, Mutex* fl_lock,
95 int process_completed_threshold,
96 int max_completed_queue,
97 Mutex* lock, PtrQueueSet* fl_owner = NULL);
98
99 // The number of parallel ids that can be claimed to allow collector or
100 // mutator threads to do card-processing work.
101 static uint num_par_ids();
102
103 static void handle_zero_index_for_thread(JavaThread* t);
104
105 // Register "blk" as "the closure" for all queues. Only one such closure
106 // is allowed. The "apply_closure_to_completed_buffer" method will apply
107 // this closure to a completed buffer, and "iterate_closure_all_threads"
108 // applies it to partially-filled buffers (the latter should only be done
109 // with the world stopped).
110 void set_closure(CardTableEntryClosure* closure);
111
112 // If there is a registered closure for buffers, apply it to all entries
113 // in all currently-active buffers. This should only be applied at a
114 // safepoint. (Currently must not be called in parallel; this should
115 // change in the future.) If "consume" is true, processed entries are
116 // discarded.
117 void iterate_closure_all_threads(bool consume = true,
118 uint worker_i = 0);
119
120 // If there exists some completed buffer, pop it, then apply the
121 // registered closure to all its elements, nulling out those elements
122 // processed. If all elements are processed, returns "true". If no
123 // completed buffers exist, returns false. If a completed buffer exists,
124 // but is only partially completed before a "yield" happens, the
125 // partially completed buffer (with its processed elements set to NULL)
126 // is returned to the completed buffer set, and this call returns false.
127 bool apply_closure_to_completed_buffer(uint worker_i = 0,
128 int stop_at = 0,
129 bool during_pause = false);
130
131 // If there exists some completed buffer, pop it, then apply the
132 // specified closure to all its elements, nulling out those elements
133 // processed. If all elements are processed, returns "true". If no
134 // completed buffers exist, returns false. If a completed buffer exists,
135 // but is only partially completed before a "yield" happens, the
136 // partially completed buffer (with its processed elements set to NULL)
137 // is returned to the completed buffer set, and this call returns false.
138 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
139 uint worker_i = 0,
140 int stop_at = 0,
141 bool during_pause = false);
142
143 // Helper routine for the above.
144 bool apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
145 uint worker_i,
146 BufferNode* nd);
147
148 BufferNode* get_completed_buffer(int stop_at);
149
150 // Applies the current closure to all completed buffers,
151 // non-consumptively.
152 void apply_closure_to_all_completed_buffers();
153
154 DirtyCardQueue* shared_dirty_card_queue() {
155 return &_shared_dirty_card_queue;
156 }
157
158 // Deallocate any completed log buffers
159 void clear();
160
161 // If a full collection is happening, reset partial logs, and ignore
162 // completed ones: the full collection will make them all irrelevant.
163 void abandon_logs();
164
165 // If any threads have partial logs, add them to the global list of logs.
166 void concatenate_logs();
167 void clear_n_completed_buffers() { _n_completed_buffers = 0;}
168
169 jint processed_buffers_mut() {
170 return _processed_buffers_mut;
171 }
172 jint processed_buffers_rs_thread() {
173 return _processed_buffers_rs_thread;
174 }
175
176 };
177
178 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_DIRTYCARDQUEUE_HPP