1 /* 2 * Copyright (c) 2013, 2015, Red Hat, Inc. and/or its affiliates. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGION_HPP 25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGION_HPP 26 27 #include "gc/shared/space.hpp" 28 #include "memory/universe.hpp" 29 #include "utilities/sizes.hpp" 30 31 class ShenandoahHeapRegion : public ContiguousSpace { 32 private: 33 static Monitor _mem_protect_lock; 34 35 public: 36 static size_t RegionSizeBytes; 37 static size_t RegionSizeShift; 38 39 private: 40 ShenandoahHeap* _heap; 41 size_t _region_number; 42 volatile jint _live_data; 43 MemRegion reserved; 44 45 bool _humongous_start; 46 bool _humongous_continuation; 47 48 bool _recycled; 49 bool _root; 50 51 HeapWord* _new_top; 52 53 volatile jint _critical_pins; 54 55 #ifdef ASSERT 56 int _mem_protection_level; 57 #endif 58 59 public: 60 ShenandoahHeapRegion(ShenandoahHeap* heap, HeapWord* start, size_t regionSize, size_t index); 61 62 static void setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size); 63 64 size_t region_number() const; 65 66 // Allocation (return NULL if full) 67 inline HeapWord* allocate(size_t word_size); 68 69 // Roll back the previous allocation of an object with specified size. 70 // Returns TRUE when successful, FALSE if not successful or not supported. 71 bool rollback_allocation(uint size); 72 73 void clear_live_data(); 74 void set_live_data(size_t s); 75 inline void increase_live_data_words(jint s); 76 77 void set_recently_allocated(bool value); 78 bool is_recently_allocated() const; 79 80 bool has_live() const; 81 size_t get_live_data_bytes() const; 82 size_t get_live_data_words() const; 83 84 void print_on(outputStream* st) const; 85 86 size_t garbage() const; 87 88 void recycle(); 89 90 void object_iterate_interruptible(ObjectClosure* blk, bool allow_cancel); 91 92 HeapWord* object_iterate_careful(ObjectClosureCareful* cl); 93 void oop_iterate(ExtendedOopClosure* cl); 94 95 private: 96 void oop_iterate_objects(ExtendedOopClosure* cl); 97 void oop_iterate_humongous(ExtendedOopClosure* cl); 98 99 public: 100 HeapWord* block_start_const(const void* p) const; 101 102 // Just before GC we need to fill the current region. 103 void fill_region(); 104 105 bool in_collection_set() const; 106 107 void set_in_collection_set(bool b); 108 109 void set_humongous_start(bool start); 110 void set_humongous_continuation(bool continuation); 111 112 bool is_humongous() const; 113 bool is_humongous_start() const; 114 bool is_humongous_continuation() const; 115 116 #ifdef ASSERT 117 void memProtectionOn(); 118 void memProtectionOff(); 119 #endif 120 121 // The following are for humongous regions. We need to save the 122 markOop saved_mark_word; 123 void save_mark_word(oop obj) {saved_mark_word = obj->mark();} 124 markOop mark_word() {return saved_mark_word;} 125 126 virtual CompactibleSpace* next_compaction_space() const; 127 128 // Override for scan_and_forward support. 129 void prepare_for_compaction(CompactPoint* cp); 130 void adjust_pointers(); 131 void compact(); 132 133 void set_new_top(HeapWord* new_top) { _new_top = new_top; } 134 HeapWord* new_top() const { return _new_top; } 135 136 void pin(); 137 void unpin(); 138 139 bool is_pinned(); 140 141 void set_root(bool r) { 142 _root = r; 143 } 144 bool is_root() { 145 return _root; 146 } 147 }; 148 149 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEAPREGION_HPP