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_CONCURRENTMARKTHREAD_HPP 26 #define SHARE_VM_GC_G1_CONCURRENTMARKTHREAD_HPP 27 28 #include "gc/shared/concurrentGCThread.hpp" 29 30 // The Concurrent Mark GC Thread triggers the parallel G1CMConcurrentMarkingTasks 31 // as well as handling various marking cleanup. 32 33 class G1ConcurrentMark; 34 class G1CollectorPolicy; 35 36 class ConcurrentMarkThread: public ConcurrentGCThread { 37 friend class VMStructs; 38 39 double _vtime_start; // Initial virtual time. 40 double _vtime_accum; // Accumulated virtual time. 41 42 double _vtime_mark_accum; 43 44 public: 45 virtual void run(); 46 47 private: 48 G1ConcurrentMark* _cm; 49 50 enum State { 51 Idle, 52 Started, 53 InProgress 54 }; 55 56 volatile State _state; 57 58 void sleepBeforeNextCycle(); 59 void delay_to_keep_mmu(G1CollectorPolicy* g1_policy, bool remark); 60 61 void run_service(); 62 void stop_service(); 63 64 static SurrogateLockerThread* _slt; 65 66 public: 67 // Constructor 68 ConcurrentMarkThread(G1ConcurrentMark* cm); 69 70 static void makeSurrogateLockerThread(TRAPS); 71 static SurrogateLockerThread* slt() { return _slt; } 72 73 // Total virtual time so far for this thread and concurrent marking tasks. 74 double vtime_accum(); 75 // Marking virtual time so far this thread and concurrent marking tasks. 76 double vtime_mark_accum(); 77 78 G1ConcurrentMark* cm() { return _cm; } 79 80 void set_idle() { assert(_state != Started, "must not be starting a new cycle"); _state = Idle; } 81 bool idle() { return _state == Idle; } 82 void set_started() { assert(_state == Idle, "cycle in progress"); _state = Started; } 83 bool started() { return _state == Started; } 84 void set_in_progress() { assert(_state == Started, "must be starting a cycle"); _state = InProgress; } 85 bool in_progress() { return _state == InProgress; } 86 87 // Returns true from the moment a marking cycle is 88 // initiated (during the initial-mark pause when started() is set) 89 // to the moment when the cycle completes (just after the next 90 // marking bitmap has been cleared and in_progress() is 91 // cleared). While during_cycle() is true we will not start another cycle 92 // so that cycles do not overlap. We cannot use just in_progress() 93 // as the CM thread might take some time to wake up before noticing 94 // that started() is set and set in_progress(). 95 bool during_cycle() { return !idle(); } 96 97 // shutdown 98 void stop(); 99 }; 100 101 #endif // SHARE_VM_GC_G1_CONCURRENTMARKTHREAD_HPP