1 /*
2 * Copyright (c) 2001, 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.
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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_G1_DIRTYCARDQUEUE_HPP
26 #define SHARE_VM_GC_G1_DIRTYCARDQUEUE_HPP
27
28 #include "gc/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 // Flush before destroying; queue may be used to capture pending work while
51 // doing something else, with auto-flush on completion.
52 ~DirtyCardQueue() { if (!is_permanent()) flush(); }
53
54 // Process queue entries and release resources.
55 void flush() { flush_impl(); }
56
57 // Apply the closure to all elements, and reset the index to make the
58 // buffer empty. If a closure application returns "false", return
59 // "false" immediately, halting the iteration. If "consume" is true,
60 // deletes processed entries from logs.
61 bool apply_closure(CardTableEntryClosure* cl,
62 bool consume = true,
63 uint worker_i = 0);
64
65 // Apply the closure to all elements of "buf", down to "index"
66 // (inclusive.) If returns "false", then a closure application returned
67 // "false", and we return immediately. If "consume" is true, entries are
68 // set to NULL as they are processed, so they will not be processed again
69 // later.
70 static bool apply_closure_to_buffer(CardTableEntryClosure* cl,
71 void** buf, size_t index, size_t sz,
72 bool consume = true,
73 uint worker_i = 0);
74 void **get_buf() { return _buf;}
75 void set_buf(void **buf) {_buf = buf;}
76 size_t get_index() { return _index;}
77 void reinitialize() { _buf = 0; _sz = 0; _index = 0;}
78 };
79
80
81
82 class DirtyCardQueueSet: public PtrQueueSet {
83 DirtyCardQueue _shared_dirty_card_queue;
84
85 // Override.
86 bool mut_process_buffer(void** buf);
87
88 // Protected by the _cbl_mon.
89 FreeIdSet* _free_ids;
90
91 // The number of completed buffers processed by mutator and rs thread,
92 // respectively.
93 jint _processed_buffers_mut;
94 jint _processed_buffers_rs_thread;
95
96 // Current buffer node used for parallel iteration.
97 BufferNode* volatile _cur_par_buffer_node;
98
99 bool _should_do_processing;
100 public:
101 DirtyCardQueueSet(bool notify_when_complete = true);
102
103 void initialize(bool should_do_processing, Monitor* cbl_mon, Mutex* fl_lock,
104 int process_completed_threshold,
105 int max_completed_queue,
106 Mutex* lock, PtrQueueSet* fl_owner = NULL);
107
108 // The number of parallel ids that can be claimed to allow collector or
109 // mutator threads to do card-processing work.
110 static uint num_par_ids();
111
112 static void handle_zero_index_for_thread(JavaThread* t);
113
114 // Apply the given closure to all entries in all currently-active buffers.
115 // This should only be applied at a safepoint. (Currently must not be called
116 // in parallel; this should change in the future.) If "consume" is true,
117 // processed entries are discarded.
118 void iterate_closure_all_threads(CardTableEntryClosure* cl,
119 bool consume = true,
120 uint worker_i = 0);
121
122 // If there exists some completed buffer, pop it, then apply the
123 // specified closure to all its elements, nulling out those elements
124 // processed. If all elements are processed, returns "true". If no
125 // completed buffers exist, returns false. If a completed buffer exists,
126 // but is only partially completed before a "yield" happens, the
127 // partially completed buffer (with its processed elements set to NULL)
128 // is returned to the completed buffer set, and this call returns false.
129 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
130 uint worker_i = 0,
131 int stop_at = 0,
132 bool during_pause = false);
133
134 // Helper routine for the above.
135 bool apply_closure_to_completed_buffer_helper(CardTableEntryClosure* cl,
136 uint worker_i,
137 BufferNode* nd);
138
139 BufferNode* get_completed_buffer(int stop_at);
140
141 // Applies the current closure to all completed buffers,
142 // non-consumptively.
143 void apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl);
144
145 void reset_for_par_iteration() { _cur_par_buffer_node = _completed_buffers_head; }
146 // Applies the current closure to all completed buffers, non-consumptively.
147 // Parallel version.
148 void par_apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl);
149
150 DirtyCardQueue* shared_dirty_card_queue() {
151 return &_shared_dirty_card_queue;
152 }
153
154 // Deallocate any completed log buffers
155 void clear();
156
157 // If a full collection is happening, reset partial logs, and ignore
158 // completed ones: the full collection will make them all irrelevant.
159 void abandon_logs();
160
161 // If any threads have partial logs, add them to the global list of logs.
162 void concatenate_logs();
163 void clear_n_completed_buffers() { _n_completed_buffers = 0;}
164
165 jint processed_buffers_mut() {
166 return _processed_buffers_mut;
167 }
168 jint processed_buffers_rs_thread() {
169 return _processed_buffers_rs_thread;
170 }
171
172 };
173
174 #endif // SHARE_VM_GC_G1_DIRTYCARDQUEUE_HPP