1 /* 2 * Copyright (c) 2014, 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_G1REGIONTOSPACEMAPPER_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1REGIONTOSPACEMAPPER_HPP 27 28 #include "gc_implementation/g1/g1PageBasedVirtualSpace.hpp" 29 #include "utilities/debug.hpp" 30 31 class G1MappingChangedListener VALUE_OBJ_CLASS_SPEC { 32 public: 33 // Fired after commit of the memory, i.e. the memory this listener is registered 34 // for can be accessed. 35 virtual void on_commit(uint start_idx, size_t num_regions) = 0; 36 }; 37 38 // Maps region based commit/uncommit requests to the underlying page sized virtual 39 // space. 40 class G1RegionToSpaceMapper : public CHeapObj<mtGC>{ 41 private: 42 G1MappingChangedListener* _listener; 43 protected: 44 // Backing storage. 45 G1PageBasedVirtualSpace _storage; 46 size_t _commit_granularity; 47 size_t _region_granularity; 48 // Mapping management 49 BitMap _commit_map; 50 51 G1RegionToSpaceMapper(ReservedSpace rs, size_t commit_granularity, size_t region_granularity, MemoryType type); 52 53 void fire_on_commit(uint start_idx, size_t num_regions); 54 public: 55 MemRegion reserved() { return _storage.reserved(); } 56 57 void set_mapping_changed_listener(G1MappingChangedListener* listener) { _listener = listener; } 58 59 virtual ~G1RegionToSpaceMapper() { 60 _commit_map.resize(0, /* in_resource_area */ false); 61 } 62 63 bool is_committed(uintptr_t idx) const { 64 return _commit_map.at(idx); 65 } 66 67 virtual void commit_regions(uintptr_t start_idx, size_t num_regions = 1) = 0; 68 virtual void uncommit_regions(uintptr_t start_idx, size_t num_regions = 1) = 0; 69 70 // Creates an appropriate G1RegionToSpaceMapper for the given parameters. 71 // The byte_translation_factor defines how many bytes in a region correspond to 72 // a single byte in the data structure this mapper is for. 73 // Eg. in the card table, this value corresponds to the size a single card 74 // table entry corresponds to. 75 static G1RegionToSpaceMapper* create_mapper(ReservedSpace rs, 76 size_t os_commit_granularity, 77 size_t region_granularity, 78 size_t byte_translation_factor, 79 MemoryType type); 80 }; 81 82 #endif /* SHARE_VM_GC_IMPLEMENTATION_G1_G1REGIONTOSPACEMAPPER_HPP */