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
21 * questions.
22 *
23 */
24
25 class FreeIdSet;
26
27 // A closure class for processing card table entries. Note that we don't
28 // require these closure objects to be stack-allocated.
29 class CardTableEntryClosure: public CHeapObj {
30 public:
31 // Process the card whose card table entry is "card_ptr". If returns
32 // "false", terminate the iteration early.
33 virtual bool do_card_ptr(jbyte* card_ptr, int worker_i = 0) = 0;
34 };
35
36 // A ptrQueue whose elements are "oops", pointers to object heads.
37 class DirtyCardQueue: public PtrQueue {
38 public:
39 DirtyCardQueue(PtrQueueSet* qset_, bool perm = false) :
40 // Dirty card queues are always active, so we create them with their
41 // active field set to true.
42 PtrQueue(qset_, perm, true /* active */) { }
43
44 // Apply the closure to all elements, and reset the index to make the
45 // buffer empty. If a closure application returns "false", return
46 // "false" immediately, halting the iteration. If "consume" is true,
47 // deletes processed entries from logs.
48 bool apply_closure(CardTableEntryClosure* cl,
49 bool consume = true,
50 size_t worker_i = 0);
51
52 // Apply the closure to all elements of "buf", down to "index"
53 // (inclusive.) If returns "false", then a closure application returned
54 // "false", and we return immediately. If "consume" is true, entries are
55 // set to NULL as they are processed, so they will not be processed again
56 // later.
57 static bool apply_closure_to_buffer(CardTableEntryClosure* cl,
58 void** buf, size_t index, size_t sz,
59 bool consume = true,
60 int worker_i = 0);
61 void **get_buf() { return _buf;}
62 void set_buf(void **buf) {_buf = buf;}
63 size_t get_index() { return _index;}
64 void reinitialize() { _buf = 0; _sz = 0; _index = 0;}
65 };
66
67
68
69 class DirtyCardQueueSet: public PtrQueueSet {
70 CardTableEntryClosure* _closure;
71
72 DirtyCardQueue _shared_dirty_card_queue;
73
74 // Override.
75 bool mut_process_buffer(void** buf);
76
77 // Protected by the _cbl_mon.
78 FreeIdSet* _free_ids;
79
80 // The number of completed buffers processed by mutator and rs thread,
81 // respectively.
82 jint _processed_buffers_mut;
83 jint _processed_buffers_rs_thread;
84
85 public:
86 DirtyCardQueueSet(bool notify_when_complete = true);
87
88 void initialize(Monitor* cbl_mon, Mutex* fl_lock,
89 int process_completed_threshold,
90 int max_completed_queue,
91 Mutex* lock, PtrQueueSet* fl_owner = NULL);
92
93 // The number of parallel ids that can be claimed to allow collector or
94 // mutator threads to do card-processing work.
95 static size_t num_par_ids();
96
97 static void handle_zero_index_for_thread(JavaThread* t);
98
99 // Register "blk" as "the closure" for all queues. Only one such closure
100 // is allowed. The "apply_closure_to_completed_buffer" method will apply
101 // this closure to a completed buffer, and "iterate_closure_all_threads"
102 // applies it to partially-filled buffers (the latter should only be done
103 // with the world stopped).
104 void set_closure(CardTableEntryClosure* closure);
105
106 // If there is a registered closure for buffers, apply it to all entries
107 // in all currently-active buffers. This should only be applied at a
108 // safepoint. (Currently must not be called in parallel; this should
109 // change in the future.) If "consume" is true, processed entries are
110 // discarded.
111 void iterate_closure_all_threads(bool consume = true,
112 size_t worker_i = 0);
113
114 // If there exists some completed buffer, pop it, then apply the
115 // registered closure to all its elements, nulling out those elements
116 // processed. If all elements are processed, returns "true". If no
117 // completed buffers exist, returns false. If a completed buffer exists,
118 // but is only partially completed before a "yield" happens, the
119 // partially completed buffer (with its processed elements set to NULL)
120 // is returned to the completed buffer set, and this call returns false.
121 bool apply_closure_to_completed_buffer(int worker_i = 0,
122 int stop_at = 0,
123 bool during_pause = false);
124
125 // If there exists some completed buffer, pop it, then apply the
126 // specified closure to all its elements, nulling out those elements
127 // processed. If all elements are processed, returns "true". If no
128 // completed buffers exist, returns false. If a completed buffer exists,
129 // but is only partially completed before a "yield" happens, the
130 // partially completed buffer (with its processed elements set to NULL)
131 // is returned to the completed buffer set, and this call returns false.
132 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
133 int worker_i = 0,
134 int stop_at = 0,
135 bool during_pause = false);
136
137 // Helper routine for the above.
138 bool apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
139 int worker_i,
140 BufferNode* nd);
141
142 BufferNode* get_completed_buffer(int stop_at);
143
144 // Applies the current closure to all completed buffers,
145 // non-consumptively.
146 void apply_closure_to_all_completed_buffers();
147
148 DirtyCardQueue* shared_dirty_card_queue() {
149 return &_shared_dirty_card_queue;
150 }
151
152 // Deallocate any completed log buffers
153 void clear();
154
155 // If a full collection is happening, reset partial logs, and ignore
156 // completed ones: the full collection will make them all irrelevant.
157 void abandon_logs();
158
159 // If any threads have partial logs, add them to the global list of logs.
160 void concatenate_logs();
161 void clear_n_completed_buffers() { _n_completed_buffers = 0;}
162
163 jint processed_buffers_mut() {
164 return _processed_buffers_mut;
165 }
166 jint processed_buffers_rs_thread() {
167 return _processed_buffers_rs_thread;
168 }
169
170 };