1 /* 2 * Copyright (c) 2001, 2010, 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_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP 27 28 #include "gc_implementation/shared/concurrentGCThread.hpp" 29 30 // The Concurrent ZF Thread. Performs concurrent zero-filling. 31 32 class ConcurrentZFThread: public ConcurrentGCThread { 33 friend class VMStructs; 34 friend class ZeroFillRegionClosure; 35 36 private: 37 38 // Zero fill the heap region. 39 void processHeapRegion(HeapRegion* r); 40 41 // Stats 42 // Allocation (protected by heap lock). 43 static int _region_allocs; // Number of regions allocated 44 static int _sync_zfs; // Synchronous zero-fills + 45 static int _zf_waits; // Wait for conc zero-fill completion. 46 47 // Number of regions CFZ thread fills. 48 static int _regions_filled; 49 50 double _vtime_start; // Initial virtual time. 51 52 // These are static because the "print_summary_info" method is, and 53 // it currently assumes there is only one ZF thread. We'll change when 54 // we need to. 55 static double _vtime_accum; // Initial virtual time. 56 static double vtime_accum() { return _vtime_accum; } 57 58 // Offer yield for GC. Returns true if yield occurred. 59 bool offer_yield(); 60 61 public: 62 // Constructor 63 ConcurrentZFThread(); 64 65 // Main loop. 66 virtual void run(); 67 68 // Printing 69 void print_on(outputStream* st) const; 70 void print() const; 71 72 // Waits until "r" has been zero-filled. Requires caller to hold the 73 // ZF_mon. 74 static void wait_for_ZF_completed(HeapRegion* r); 75 76 // Get or clear the current unclean region. Should be done 77 // while holding the ZF_needed_mon lock. 78 79 // shutdown 80 void stop(); 81 82 // Stats 83 static void note_region_alloc() {_region_allocs++; } 84 static void note_sync_zfs() { _sync_zfs++; } 85 static void note_zf_wait() { _zf_waits++; } 86 static void note_region_filled() { _regions_filled++; } 87 88 static void print_summary_info(); 89 }; 90 91 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP