1 /*
2 * Copyright (c) 2001, 2017, 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_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 class DirtyCardQueueSet;
33
34 // A closure class for processing card table entries. Note that we don't
35 // require these closure objects to be stack-allocated.
36 class CardTableEntryClosure: public CHeapObj<mtGC> {
37 public:
38 // Process the card whose card table entry is "card_ptr". If returns
39 // "false", terminate the iteration early.
40 virtual bool do_card_ptr(jbyte* card_ptr, uint worker_i) = 0;
41 };
42
43 // A ptrQueue whose elements are "oops", pointers to object heads.
44 class DirtyCardQueue: public PtrQueue {
45 public:
46 DirtyCardQueue(DirtyCardQueueSet* qset, bool permanent = false);
47
48 // Flush before destroying; queue may be used to capture pending work while
49 // doing something else, with auto-flush on completion.
50 ~DirtyCardQueue();
51
52 // Process queue entries and release resources.
53 void flush() { flush_impl(); }
54
55 // Compiler support.
56 static ByteSize byte_offset_of_index() {
57 return PtrQueue::byte_offset_of_index<DirtyCardQueue>();
58 }
59 using PtrQueue::byte_width_of_index;
60
61 static ByteSize byte_offset_of_buf() {
62 return PtrQueue::byte_offset_of_buf<DirtyCardQueue>();
63 }
64 using PtrQueue::byte_width_of_buf;
65
66 };
67
68
69
70 class DirtyCardQueueSet: public PtrQueueSet {
71 DirtyCardQueue _shared_dirty_card_queue;
72
73 // Apply the closure to the elements of "node" from it's index to
74 // buffer_size. If all closure applications return true, then
75 // returns true. Stops processing after the first closure
76 // application that returns false, and returns false from this
77 // function. If "consume" is true, the node's index is updated to
78 // exclude the processed elements, e.g. up to the element for which
79 // the closure returned false.
80 bool apply_closure_to_buffer(CardTableEntryClosure* cl,
81 BufferNode* node,
82 bool consume,
83 uint worker_i = 0);
84
85 // If there are more than stop_at completed buffers, pop one, apply
86 // the specified closure to its active elements, and return true.
87 // Otherwise return false.
88 //
89 // A completely processed buffer is freed. However, if a closure
90 // invocation returns false, processing is stopped and the partially
91 // processed buffer (with its index updated to exclude the processed
92 // elements, e.g. up to the element for which the closure returned
93 // false) is returned to the completed buffer set.
94 //
95 // If during_pause is true, stop_at must be zero, and the closure
96 // must never return false.
97 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl,
98 uint worker_i,
99 size_t stop_at,
100 bool during_pause);
101
102 bool mut_process_buffer(BufferNode* node);
103
104 // Protected by the _cbl_mon.
105 FreeIdSet* _free_ids;
106
107 // The number of completed buffers processed by mutator and rs thread,
108 // respectively.
109 jint _processed_buffers_mut;
110 jint _processed_buffers_rs_thread;
111
112 // Current buffer node used for parallel iteration.
113 BufferNode* volatile _cur_par_buffer_node;
114
115 void concatenate_log(DirtyCardQueue& dcq);
116
117 public:
118 DirtyCardQueueSet(bool notify_when_complete = true);
119
120 void initialize(Monitor* cbl_mon,
121 Mutex* fl_lock,
122 int process_completed_threshold,
123 int max_completed_queue,
124 Mutex* lock,
125 DirtyCardQueueSet* fl_owner,
126 bool init_free_ids = false);
127
128 // The number of parallel ids that can be claimed to allow collector or
129 // mutator threads to do card-processing work.
130 static uint num_par_ids();
131
132 static void handle_zero_index_for_thread(JavaThread* t);
133
134 // Apply G1RefineCardConcurrentlyClosure to completed buffers until there are stop_at
135 // completed buffers remaining.
136 bool refine_completed_buffer_concurrently(uint worker_i, size_t stop_at);
137
138 // Apply the given closure to all completed buffers. The given closure's do_card_ptr
139 // must never return false. Must only be called during GC.
140 bool apply_closure_during_gc(CardTableEntryClosure* cl, uint worker_i);
141
142 BufferNode* get_completed_buffer(size_t stop_at);
143
144 void reset_for_par_iteration() { _cur_par_buffer_node = _completed_buffers_head; }
145 // Applies the current closure to all completed buffers, non-consumptively.
146 // Can be used in parallel, all callers using the iteration state initialized
147 // by reset_for_par_iteration.
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