1 /*
2 * Copyright (c) 2001, 2010, 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
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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 {
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, int 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 PtrQueue(qset_, perm)
47 {
48 // Dirty card queues are always active.
49 _active = true;
50 }
51 // Apply the closure to all elements, and reset the index to make the
52 // buffer empty. If a closure application returns "false", return
53 // "false" immediately, halting the iteration. If "consume" is true,
54 // deletes processed entries from logs.
55 bool apply_closure(CardTableEntryClosure* cl,
56 bool consume = true,
57 size_t worker_i = 0);
58
59 // Apply the closure to all elements of "buf", down to "index"
60 // (inclusive.) If returns "false", then a closure application returned
61 // "false", and we return immediately. If "consume" is true, entries are
62 // set to NULL as they are processed, so they will not be processed again
63 // later.
64 static bool apply_closure_to_buffer(CardTableEntryClosure* cl,
65 void** buf, size_t index, size_t sz,
66 bool consume = true,
67 int worker_i = 0);
68 void **get_buf() { return _buf;}
69 void set_buf(void **buf) {_buf = buf;}
70 size_t get_index() { return _index;}
71 void reinitialize() { _buf = 0; _sz = 0; _index = 0;}
72 };
73
74
75
76 class DirtyCardQueueSet: public PtrQueueSet {
77 CardTableEntryClosure* _closure;
78
79 DirtyCardQueue _shared_dirty_card_queue;
80
81 // Override.
82 bool mut_process_buffer(void** buf);
83
84 // Protected by the _cbl_mon.
85 FreeIdSet* _free_ids;
86
87 // The number of completed buffers processed by mutator and rs thread,
88 // respectively.
89 jint _processed_buffers_mut;
90 jint _processed_buffers_rs_thread;
91
92 public:
93 DirtyCardQueueSet(bool notify_when_complete = true);
94
95 void initialize(Monitor* cbl_mon, Mutex* fl_lock,
96 int process_completed_threshold,
97 int max_completed_queue,
98 Mutex* lock, PtrQueueSet* fl_owner = NULL);
99
100 // The number of parallel ids that can be claimed to allow collector or
101 // mutator threads to do card-processing work.
102 static size_t num_par_ids();
103
104 static void handle_zero_index_for_thread(JavaThread* t);
105
106 // Register "blk" as "the closure" for all queues. Only one such closure
107 // is allowed. The "apply_closure_to_completed_buffer" method will apply
108 // this closure to a completed buffer, and "iterate_closure_all_threads"
109 // applies it to partially-filled buffers (the latter should only be done
110 // with the world stopped).
111 void set_closure(CardTableEntryClosure* closure);
112
113 // If there is a registered closure for buffers, apply it to all entries
114 // in all currently-active buffers. This should only be applied at a
115 // safepoint. (Currently must not be called in parallel; this should
116 // change in the future.) If "consume" is true, processed entries are
117 // discarded.
118 void iterate_closure_all_threads(bool consume = true,
119 size_t worker_i = 0);
120
121 // If there exists some completed buffer, pop it, then apply the
122 // registered closure to all its elements, nulling out those elements
123 // processed. If all elements are processed, returns "true". If no
124 // completed buffers exist, returns false. If a completed buffer exists,
125 // but is only partially completed before a "yield" happens, the
126 // partially completed buffer (with its processed elements set to NULL)
127 // is returned to the completed buffer set, and this call returns false.
128 bool apply_closure_to_completed_buffer(int worker_i = 0,
129 int stop_at = 0,
130 bool during_pause = false);
131
132 // If there exists some completed buffer, pop it, then apply the
133 // specified closure to all its elements, nulling out those elements
134 // processed. If all elements are processed, returns "true". If no
135 // completed buffers exist, returns false. If a completed buffer exists,
136 // but is only partially completed before a "yield" happens, the
137 // partially completed buffer (with its processed elements set to NULL)
138 // is returned to the completed buffer set, and this call returns false.
139 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
140 int worker_i = 0,
141 int stop_at = 0,
142 bool during_pause = false);
143
144 // Helper routine for the above.
145 bool apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
146 int worker_i,
147 BufferNode* nd);
148
149 BufferNode* get_completed_buffer(int stop_at);
150
151 // Applies the current closure to all completed buffers,
152 // non-consumptively.
153 void apply_closure_to_all_completed_buffers();
154
155 DirtyCardQueue* shared_dirty_card_queue() {
156 return &_shared_dirty_card_queue;
157 }
158
159 // Deallocate any completed log buffers
160 void clear();
161
162 // If a full collection is happening, reset partial logs, and ignore
163 // completed ones: the full collection will make them all irrelevant.
164 void abandon_logs();
165
166 // If any threads have partial logs, add them to the global list of logs.
167 void concatenate_logs();
168 void clear_n_completed_buffers() { _n_completed_buffers = 0;}
169
170 jint processed_buffers_mut() {
171 return _processed_buffers_mut;
172 }
173 jint processed_buffers_rs_thread() {
174 return _processed_buffers_rs_thread;
175 }
176
177 };
178
179 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_DIRTYCARDQUEUE_HPP