1 /*
2 * Copyright (c) 2001, 2019, 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_GC_G1_G1DIRTYCARDQUEUE_HPP
26 #define SHARE_GC_G1_G1DIRTYCARDQUEUE_HPP
27
28 #include "gc/g1/g1FreeIdSet.hpp"
29 #include "gc/shared/ptrQueue.hpp"
30 #include "memory/allocation.hpp"
31
32 class G1CardTableEntryClosure;
33 class G1DirtyCardQueueSet;
34 class G1RedirtyCardsQueueSet;
35 class Thread;
36 class Monitor;
37
38 // A ptrQueue whose elements are "oops", pointers to object heads.
39 class G1DirtyCardQueue: public PtrQueue {
40 protected:
41 virtual void handle_completed_buffer();
42
43 public:
44 G1DirtyCardQueue(G1DirtyCardQueueSet* qset);
45
46 // Flush before destroying; queue may be used to capture pending work while
47 // doing something else, with auto-flush on completion.
48 ~G1DirtyCardQueue();
49
50 // Process queue entries and release resources.
51 void flush() { flush_impl(); }
52
53 inline G1DirtyCardQueueSet* dirty_card_qset() const;
54
55 // Compiler support.
56 static ByteSize byte_offset_of_index() {
57 return PtrQueue::byte_offset_of_index<G1DirtyCardQueue>();
58 }
59 using PtrQueue::byte_width_of_index;
60
61 static ByteSize byte_offset_of_buf() {
62 return PtrQueue::byte_offset_of_buf<G1DirtyCardQueue>();
63 }
64 using PtrQueue::byte_width_of_buf;
65
66 };
67
68 class G1DirtyCardQueueSet: public PtrQueueSet {
69 Monitor* _cbl_mon; // Protects the list and count members.
70 BufferNode* _completed_buffers_head;
71 BufferNode* _completed_buffers_tail;
72
73 // Number of actual cards in the list of completed buffers.
74 volatile size_t _num_cards;
75
76 size_t _process_cards_threshold;
77 volatile bool _process_completed_buffers;
78
79 void abandon_completed_buffers();
80
81 // Apply the closure to the elements of "node" from it's index to
82 // buffer_size. If all closure applications return true, then
83 // returns true. Stops processing after the first closure
84 // application that returns false, and returns false from this
85 // function. The node's index is updated to exclude the processed
86 // elements, e.g. up to the element for which the closure returned
87 // false, or one past the last element if the closure always
88 // returned true.
89 bool apply_closure_to_buffer(G1CardTableEntryClosure* cl,
90 BufferNode* node,
91 uint worker_i = 0);
92
93 // If there are more than stop_at completed buffers, pop one, apply
94 // the specified closure to its active elements, and return true.
95 // Otherwise return false.
96 //
97 // A completely processed buffer is freed. However, if a closure
98 // invocation returns false, processing is stopped and the partially
99 // processed buffer (with its index updated to exclude the processed
100 // elements, e.g. up to the element for which the closure returned
101 // false) is returned to the completed buffer set.
102 //
103 // If during_pause is true, stop_at must be zero, and the closure
104 // must never return false.
105 bool apply_closure_to_completed_buffer(G1CardTableEntryClosure* cl,
106 uint worker_i,
107 size_t stop_at,
108 bool during_pause);
109
110 bool mut_process_buffer(BufferNode* node);
111
112 // If the queue contains more cards than configured here, the
113 // mutator must start doing some of the concurrent refinement work.
114 size_t _max_cards;
115 size_t _max_cards_padding;
116 static const size_t MaxCardsUnlimited = SIZE_MAX;
117
118 G1FreeIdSet _free_ids;
119
120 // The number of completed buffers processed by mutator and rs thread,
121 // respectively.
122 jint _processed_buffers_mut;
123 jint _processed_buffers_rs_thread;
124
125 public:
126 G1DirtyCardQueueSet(Monitor* cbl_mon, BufferNode::Allocator* allocator);
127 ~G1DirtyCardQueueSet();
128
129 // The number of parallel ids that can be claimed to allow collector or
130 // mutator threads to do card-processing work.
131 static uint num_par_ids();
132
133 static void handle_zero_index_for_thread(Thread* t);
134
135 // Either process the entire buffer and return true, or enqueue the
136 // buffer and return false. If the buffer is completely processed,
137 // it can be reused in place.
138 bool process_or_enqueue_completed_buffer(BufferNode* node);
139
140 virtual void enqueue_completed_buffer(BufferNode* node);
141
142 // If the number of completed buffers is > stop_at, then remove and
143 // return a completed buffer from the list. Otherwise, return NULL.
144 BufferNode* get_completed_buffer(size_t stop_at = 0);
145
146 // The number of cards in completed buffers. Read without synchronization.
147 size_t num_cards() const { return _num_cards; }
148
149 // Verify that _num_cards is equal to the sum of actual cards
150 // in the completed buffers.
151 void verify_num_cards() const NOT_DEBUG_RETURN;
152
153 bool process_completed_buffers() { return _process_completed_buffers; }
154 void set_process_completed_buffers(bool x) { _process_completed_buffers = x; }
155
156 // Get/Set the number of cards that triggers log processing.
157 // Log processing should be done when the number of cards exceeds the
158 // threshold.
159 void set_process_cards_threshold(size_t sz) {
160 _process_cards_threshold = sz;
161 }
162 size_t process_cards_threshold() const {
163 return _process_cards_threshold;
164 }
165 static const size_t ProcessCardsThresholdNever = SIZE_MAX;
166
167 // Notify the consumer if the number of buffers crossed the threshold
168 void notify_if_necessary();
169
170 void merge_bufferlists(G1RedirtyCardsQueueSet* src);
171
172 // Apply G1RefineCardConcurrentlyClosure to completed buffers until there are stop_at
173 // completed buffers remaining.
174 bool refine_completed_buffer_concurrently(uint worker_i, size_t stop_at);
175
176 // Apply the given closure to all completed buffers. The given closure's do_card_ptr
177 // must never return false. Must only be called during GC.
178 bool apply_closure_during_gc(G1CardTableEntryClosure* cl, uint worker_i);
179
180 // If a full collection is happening, reset partial logs, and release
181 // completed ones: the full collection will make them all irrelevant.
182 void abandon_logs();
183
184 // If any threads have partial logs, add them to the global list of logs.
185 void concatenate_logs();
186
187 void set_max_cards(size_t m) {
188 _max_cards = m;
189 }
190 size_t max_cards() const {
191 return _max_cards;
192 }
193
194 void set_max_cards_padding(size_t padding) {
195 _max_cards_padding = padding;
196 }
197 size_t max_cards_padding() const {
198 return _max_cards_padding;
199 }
200
201 jint processed_buffers_mut() {
202 return _processed_buffers_mut;
203 }
204 jint processed_buffers_rs_thread() {
205 return _processed_buffers_rs_thread;
206 }
207
208 };
209
210 inline G1DirtyCardQueueSet* G1DirtyCardQueue::dirty_card_qset() const {
211 return static_cast<G1DirtyCardQueueSet*>(qset());
212 }
213
214 #endif // SHARE_GC_G1_G1DIRTYCARDQUEUE_HPP