1 /* 2 * A page queue whose users take turns to access pages. 3 * 4 * Copyright (C) 2021 Paul Boddie <paul@boddie.org.uk> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA 20 */ 21 22 #pragma once 23 24 #include <condition_variable> 25 #include <mutex> 26 27 #include <fsserver/page_queue.h> 28 29 30 31 /* A queue of issued pages. */ 32 33 class PageQueueShared : public PageQueue 34 { 35 protected: 36 Queue _queue; 37 Positions _positions; 38 39 std::mutex _lock; 40 std::condition_variable _counter; 41 42 virtual bool _pop(QueueEntry *entry); 43 44 public: 45 virtual void close(Memory *memory); 46 47 virtual void pop(PageOwner **owner, Flexpage **flexpage); 48 49 virtual void push(PageOwner *owner, Flexpage *flexpage); 50 51 virtual void push_front(PageOwner *owner, Flexpage *flexpage); 52 53 virtual bool remove(PageOwner *owner, Flexpage *flexpage); 54 }; 55 56 // vim: tabstop=4 expandtab shiftwidth=4