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. 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 #ifndef SHARE_GC_G1_G1DIRTYCARDQUEUE_HPP 26 #define SHARE_GC_G1_G1DIRTYCARDQUEUE_HPP 27 28 #include "gc/g1/g1BufferNodeList.hpp" 29 #include "gc/g1/g1FreeIdSet.hpp" 30 #include "gc/shared/ptrQueue.hpp" 31 #include "memory/allocation.hpp" 32 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 // Refine the cards in "node" from it's index to buffer_size. 82 // Stops processing if SuspendibleThreadSet::should_yield() is true. 83 // Returns true if the entire buffer was processed, false if there 84 // is a pending yield request. The node's index is updated to exclude 85 // the processed elements, e.g. up to the element before processing 86 // stopped, or one past the last element if the entire buffer was 87 // processed. 88 bool refine_buffer(BufferNode* node, uint worker_id); 89 90 bool mut_process_buffer(BufferNode* node); 91 92 // If the queue contains more cards than configured here, the 93 // mutator must start doing some of the concurrent refinement work. 94 size_t _max_cards; 95 size_t _max_cards_padding; 96 static const size_t MaxCardsUnlimited = SIZE_MAX; 97 98 G1FreeIdSet _free_ids; 99 100 // The number of completed buffers processed by mutator and rs thread, 101 // respectively. 102 jint _processed_buffers_mut; 103 jint _processed_buffers_rs_thread; 104 105 public: 106 G1DirtyCardQueueSet(); 107 ~G1DirtyCardQueueSet(); 108 109 void initialize(Monitor* cbl_mon, BufferNode::Allocator* allocator); 110 111 // The number of parallel ids that can be claimed to allow collector or 112 // mutator threads to do card-processing work. 113 static uint num_par_ids(); 114 115 static void handle_zero_index_for_thread(Thread* t); 116 117 // Either process the entire buffer and return true, or enqueue the 118 // buffer and return false. If the buffer is completely processed, 119 // it can be reused in place. 120 bool process_or_enqueue_completed_buffer(BufferNode* node); 121 122 virtual void enqueue_completed_buffer(BufferNode* node); 123 124 // If the number of completed buffers is > stop_at, then remove and 125 // return a completed buffer from the list. Otherwise, return NULL. 126 BufferNode* get_completed_buffer(size_t stop_at = 0); 127 128 // The number of cards in completed buffers. Read without synchronization. 129 size_t num_cards() const { return _num_cards; } 130 131 // Verify that _num_cards is equal to the sum of actual cards 132 // in the completed buffers. 133 void verify_num_cards() const NOT_DEBUG_RETURN; 134 135 bool process_completed_buffers() { return _process_completed_buffers; } 136 void set_process_completed_buffers(bool x) { _process_completed_buffers = x; } 137 138 // Get/Set the number of cards that triggers log processing. 139 // Log processing should be done when the number of cards exceeds the 140 // threshold. 141 void set_process_cards_threshold(size_t sz) { 142 _process_cards_threshold = sz; 143 } 144 size_t process_cards_threshold() const { 145 return _process_cards_threshold; 146 } 147 static const size_t ProcessCardsThresholdNever = SIZE_MAX; 148 149 // Notify the consumer if the number of buffers crossed the threshold 150 void notify_if_necessary(); 151 152 void merge_bufferlists(G1RedirtyCardsQueueSet* src); 153 154 G1BufferNodeList take_all_completed_buffers(); 155 156 // If there are more than stop_at cards in the completed buffers, pop 157 // a buffer, refine its contents, and return true. Otherwise return 158 // false. 159 // 160 // Stops processing a buffer if SuspendibleThreadSet::should_yield(), 161 // returning the incompletely processed buffer to the completed buffer 162 // list, for later processing of the remainder. 163 bool refine_completed_buffer_concurrently(uint worker_i, size_t stop_at); 164 165 // If a full collection is happening, reset partial logs, and release 166 // completed ones: the full collection will make them all irrelevant. 167 void abandon_logs(); 168 169 // If any threads have partial logs, add them to the global list of logs. 170 void concatenate_logs(); 171 172 void set_max_cards(size_t m) { 173 _max_cards = m; 174 } 175 size_t max_cards() const { 176 return _max_cards; 177 } 178 179 void set_max_cards_padding(size_t padding) { 180 _max_cards_padding = padding; 181 } 182 size_t max_cards_padding() const { 183 return _max_cards_padding; 184 } 185 186 jint processed_buffers_mut() { 187 return _processed_buffers_mut; 188 } 189 jint processed_buffers_rs_thread() { 190 return _processed_buffers_rs_thread; 191 } 192 193 }; 194 195 inline G1DirtyCardQueueSet* G1DirtyCardQueue::dirty_card_qset() const { 196 return static_cast<G1DirtyCardQueueSet*>(qset()); 197 } 198 199 #endif // SHARE_GC_G1_G1DIRTYCARDQUEUE_HPP