1 /* 2 * Copyright (c) 2001, 2016, 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_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) = 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 // Apply the closure to all elements, and reset the index to make the 56 // buffer empty. If a closure application returns "false", return 57 // "false" immediately, halting the iteration. If "consume" is true, 58 // deletes processed entries from logs. 59 bool apply_closure(CardTableEntryClosure* cl, 60 bool consume = true, 61 uint worker_i = 0); 62 63 // Apply the closure to all elements of "buf", down to "index" 64 // (inclusive.) If returns "false", then a closure application returned 65 // "false", and we return immediately. If "consume" is true, entries are 66 // set to NULL as they are processed, so they will not be processed again 67 // later. 68 static bool apply_closure_to_buffer(CardTableEntryClosure* cl, 69 void** buf, size_t index, size_t sz, 70 bool consume = true, 71 uint worker_i = 0); 72 void **get_buf() { return _buf;} 73 size_t get_index() { return _index;} 74 void reinitialize() { _buf = 0; _sz = 0; _index = 0;} 75 76 // Compiler support. 77 static ByteSize byte_offset_of_index() { 78 return PtrQueue::byte_offset_of_index<DirtyCardQueue>(); 79 } 80 using PtrQueue::byte_width_of_index; 81 82 static ByteSize byte_offset_of_buf() { 83 return PtrQueue::byte_offset_of_buf<DirtyCardQueue>(); 84 } 85 using PtrQueue::byte_width_of_buf; 86 87 }; 88 89 90 91 class DirtyCardQueueSet: public PtrQueueSet { 92 // The closure used in mut_process_buffer(). 93 CardTableEntryClosure* _mut_process_closure; 94 95 DirtyCardQueue _shared_dirty_card_queue; 96 97 // Override. 98 bool mut_process_buffer(void** buf); 99 100 // Protected by the _cbl_mon. 101 FreeIdSet* _free_ids; 102 103 // The number of completed buffers processed by mutator and rs thread, 104 // respectively. 105 jint _processed_buffers_mut; 106 jint _processed_buffers_rs_thread; 107 108 // Current buffer node used for parallel iteration. 109 BufferNode* volatile _cur_par_buffer_node; 110 public: 111 DirtyCardQueueSet(bool notify_when_complete = true); 112 113 void initialize(CardTableEntryClosure* cl, 114 Monitor* cbl_mon, 115 Mutex* fl_lock, 116 size_t process_completed_threshold, 117 size_t max_completed_queue, 118 Mutex* lock, 119 DirtyCardQueueSet* fl_owner, 120 bool init_free_ids = false); 121 122 // The number of parallel ids that can be claimed to allow collector or 123 // mutator threads to do card-processing work. 124 static uint num_par_ids(); 125 126 static void handle_zero_index_for_thread(JavaThread* t); 127 128 // If there exists some completed buffer, pop it, then apply the 129 // specified closure to all its elements, nulling out those elements 130 // processed. If all elements are processed, returns "true". If no 131 // completed buffers exist, returns false. If a completed buffer exists, 132 // but is only partially completed before a "yield" happens, the 133 // partially completed buffer (with its processed elements set to NULL) 134 // is returned to the completed buffer set, and this call returns false. 135 bool apply_closure_to_completed_buffer(CardTableEntryClosure* cl, 136 uint worker_i, 137 size_t stop_at, 138 bool during_pause); 139 140 BufferNode* get_completed_buffer(size_t stop_at); 141 142 // Applies the current closure to all completed buffers, 143 // non-consumptively. 144 void apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl); 145 146 void reset_for_par_iteration() { _cur_par_buffer_node = _completed_buffers_head; } 147 // Applies the current closure to all completed buffers, non-consumptively. 148 // Parallel version. 149 void par_apply_closure_to_all_completed_buffers(CardTableEntryClosure* cl); 150 151 DirtyCardQueue* shared_dirty_card_queue() { 152 return &_shared_dirty_card_queue; 153 } 154 155 // Deallocate any completed log buffers 156 void clear(); 157 158 // If a full collection is happening, reset partial logs, and ignore 159 // completed ones: the full collection will make them all irrelevant. 160 void abandon_logs(); 161 162 // If any threads have partial logs, add them to the global list of logs. 163 void concatenate_logs(); 164 void clear_n_completed_buffers() { _n_completed_buffers = 0;} 165 166 jint processed_buffers_mut() { 167 return _processed_buffers_mut; 168 } 169 jint processed_buffers_rs_thread() { 170 return _processed_buffers_rs_thread; 171 } 172 173 }; 174 175 #endif // SHARE_VM_GC_G1_DIRTYCARDQUEUE_HPP