1 /* 2 * Copyright (c) 2001, 2015, 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_G1MARKSWEEP_HPP 26 #define SHARE_VM_GC_G1_G1MARKSWEEP_HPP 27 28 #include "gc/g1/g1CollectedHeap.hpp" 29 #include "gc/g1/heapRegion.hpp" 30 #include "gc/serial/genMarkSweep.hpp" 31 #include "gc/shared/generation.hpp" 32 #include "memory/universe.hpp" 33 #include "oops/markOop.hpp" 34 #include "oops/oop.hpp" 35 #include "runtime/timer.hpp" 36 #include "utilities/growableArray.hpp" 37 38 class ReferenceProcessor; 39 40 // G1MarkSweep takes care of global mark-compact garbage collection for a 41 // G1CollectedHeap using a four-phase pointer forwarding algorithm. All 42 // generations are assumed to support marking; those that can also support 43 // compaction. 44 // 45 // Class unloading will only occur when a full gc is invoked. 46 class G1PrepareCompactClosure; 47 class G1ArchiveRegionMap; 48 49 class G1MarkSweep : AllStatic { 50 public: 51 52 static void invoke_at_safepoint(ReferenceProcessor* rp, 53 bool clear_all_softrefs); 54 55 static STWGCTimer* gc_timer() { return GenMarkSweep::_gc_timer; } 56 static SerialOldTracer* gc_tracer() { return GenMarkSweep::_gc_tracer; } 57 58 // Create the _archive_region_map which is used to identify archive objects. 59 static void enable_archive_object_check(); 60 61 // Set the regions containing the specified address range as archive/non-archive. 62 static void set_range_archive(MemRegion range, bool is_archive); 63 64 // Check if an object is in an archive region using the _archive_region_map. 65 static bool in_archive_range(oop object); 66 67 // Check if archive object checking is enabled, to avoid calling in_archive_range 68 // unnecessarily. 69 static bool archive_check_enabled() { return G1MarkSweep::_archive_check_enabled; } 70 71 private: 72 static bool _archive_check_enabled; 73 static G1ArchiveRegionMap _archive_region_map; 74 75 // Mark live objects 76 static void mark_sweep_phase1(bool& marked_for_deopt, 77 bool clear_all_softrefs); 78 // Calculate new addresses 79 static void mark_sweep_phase2(); 80 // Update pointers 81 static void mark_sweep_phase3(); 82 // Move objects to new positions 83 static void mark_sweep_phase4(); 84 85 static void allocate_stacks(); 86 static void prepare_compaction(); 87 static void prepare_compaction_work(G1PrepareCompactClosure* blk); 88 }; 89 90 class G1PrepareCompactClosure : public HeapRegionClosure { 91 protected: 92 G1CollectedHeap* _g1h; 93 ModRefBarrierSet* _mrbs; 94 CompactPoint _cp; 95 uint _humongous_regions_removed; 96 97 virtual void prepare_for_compaction(HeapRegion* hr, HeapWord* end); 98 void prepare_for_compaction_work(CompactPoint* cp, HeapRegion* hr, HeapWord* end); 99 void free_humongous_region(HeapRegion* hr); 100 bool is_cp_initialized() const { return _cp.space != NULL; } 101 102 public: 103 G1PrepareCompactClosure() : 104 _g1h(G1CollectedHeap::heap()), 105 _mrbs(_g1h->g1_barrier_set()), 106 _humongous_regions_removed(0) { } 107 108 void update_sets(); 109 bool doHeapRegion(HeapRegion* hr); 110 }; 111 112 // G1ArchiveRegionMap is a boolean array used to mark G1 regions as 113 // archive regions. This allows a quick check for whether an object 114 // should not be marked because it is in an archive region. 115 class G1ArchiveRegionMap : public G1BiasedMappedArray<bool> { 116 protected: 117 bool default_value() const { return false; } 118 }; 119 120 #endif // SHARE_VM_GC_G1_G1MARKSWEEP_HPP