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
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<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() { }
46 DirtyCardQueue(PtrQueueSet* qset_, bool perm = false) :
47 // Dirty card queues are always active, so we create them with their
48 // active field set to true.
49 PtrQueue(qset_, perm, true /* active */) { }
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 uint 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 uint 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 // The closure used in mut_process_buffer().
78 CardTableEntryClosure* _mut_process_closure;
79
80 DirtyCardQueue _shared_dirty_card_queue;
81
82 // Override.
83 bool mut_process_buffer(void** buf);
84
85 // Protected by the _cbl_mon.
86 FreeIdSet* _free_ids;
87
88 // The number of completed buffers processed by mutator and rs thread,
89 // respectively.
90 jint _processed_buffers_mut;
91 jint _processed_buffers_rs_thread;
92
93 // Current buffer node used for parallel iteration.
94 BufferNode* volatile _cur_par_buffer_node;
95 public:
96 DirtyCardQueueSet(bool notify_when_complete = true);
97
98 void initialize(CardTableEntryClosure* cl, Monitor* cbl_mon, Mutex* fl_lock,
99 int process_completed_threshold,
100 int max_completed_queue,
101 Mutex* lock, PtrQueueSet* fl_owner = NULL);
102
103 // The number of parallel ids that can be claimed to allow collector or
104 // mutator threads to do card-processing work.
105 static uint num_par_ids();
106
107 static void handle_zero_index_for_thread(JavaThread* t);
108
109 // Apply the given closure to all entries in all currently-active buffers.
110 // This should only be applied at a safepoint. (Currently must not be called
111 // in parallel; this should change in the future.) If "consume" is true,
112 // processed entries are discarded.
113 void iterate_closure_all_threads(CardTableEntryClosure* cl,
114 bool consume = true,
115 uint worker_i = 0);
116
117 // If there exists some completed buffer, pop it, then apply the
118 // specified closure to all its elements, nulling out those elements
119 // processed. If all elements are processed, returns "true". If no
120 // completed buffers exist, returns false. If a completed buffer exists,
121 // but is only partially completed before a "yield" happens, the
122 // partially completed buffer (with its processed elements set to NULL)
123 // is returned to the completed buffer set, and this call returns false.
124 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
125 uint worker_i = 0,
126 int stop_at = 0,
127 bool during_pause = false);
128
129 // Helper routine for the above.
130 bool apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
131 uint worker_i,
132 BufferNode* nd);
133
134 BufferNode* get_completed_buffer(int stop_at);
135
136 // Applies the current closure to all completed buffers,
137 // non-consumptively.
138 void apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl);
139
140 void reset_for_par_iteration() { _cur_par_buffer_node = _completed_buffers_head; }
141 // Applies the current closure to all completed buffers, non-consumptively.
142 // Parallel version.
143 void par_apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl);
144
145 DirtyCardQueue* shared_dirty_card_queue() {
146 return &_shared_dirty_card_queue;
147 }
148
149 // Deallocate any completed log buffers
150 void clear();
151
152 // If a full collection is happening, reset partial logs, and ignore
153 // completed ones: the full collection will make them all irrelevant.
154 void abandon_logs();
155
156 // If any threads have partial logs, add them to the global list of logs.
157 void concatenate_logs();
158 void clear_n_completed_buffers() { _n_completed_buffers = 0;}
159
160 jint processed_buffers_mut() {
161 return _processed_buffers_mut;
162 }
163 jint processed_buffers_rs_thread() {
164 return _processed_buffers_rs_thread;
165 }
166
167 };
168
169 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_DIRTYCARDQUEUE_HPP