1 /* 2 * Copyright (c) 2018, 2024, 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_CDS_ARCHIVEHEAPLOADER_HPP 26 #define SHARE_CDS_ARCHIVEHEAPLOADER_HPP 27 28 #include "cds/filemap.hpp" 29 #include "gc/shared/gc_globals.hpp" 30 #include "memory/allocation.hpp" 31 #include "memory/allStatic.hpp" 32 #include "memory/memRegion.hpp" 33 #include "oops/oopsHierarchy.hpp" 34 #include "runtime/globals.hpp" 35 #include "utilities/bitMap.hpp" 36 #include "utilities/macros.hpp" 37 38 class FileMapInfo; 39 struct LoadedArchiveHeapRegion; 40 41 class ArchiveHeapLoader : AllStatic { 42 public: 43 // At runtime, the heap region in the CDS archive can be used in two different ways, 44 // depending on the GC type: 45 // - Mapped: (G1 only) the region is directly mapped into the Java heap 46 // - Loaded: At VM start-up, the objects in the heap region are copied into the 47 // Java heap. This is easier to implement than mapping but 48 // slightly less efficient, as the embedded pointers need to be relocated. 49 static bool can_use() { return can_map() || can_load(); } 50 51 // Can this VM map archived heap region? Currently only G1+compressed{oops,cp} 52 static bool can_map() { 53 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedClassPointers);) 54 NOT_CDS_JAVA_HEAP(return false;) 55 } 56 57 // Can this VM load the objects from archived heap region into the heap at start-up? 58 static bool can_load() NOT_CDS_JAVA_HEAP_RETURN_(false); 59 static void finish_initialization() NOT_CDS_JAVA_HEAP_RETURN; 60 static bool is_loaded() { 61 CDS_JAVA_HEAP_ONLY(return _is_loaded;) 62 NOT_CDS_JAVA_HEAP(return false;) 63 } 64 65 static bool is_in_use() { 66 return is_loaded() || is_mapped(); 67 } 68 69 static ptrdiff_t mapped_heap_delta() { 70 CDS_JAVA_HEAP_ONLY(assert(!is_loaded(), "must be")); 71 CDS_JAVA_HEAP_ONLY(assert(_mapped_heap_relocation_initialized, "must be")); 72 CDS_JAVA_HEAP_ONLY(return _mapped_heap_delta;) 73 NOT_CDS_JAVA_HEAP_RETURN_(0L); 74 } 75 76 static void set_mapped() { 77 CDS_JAVA_HEAP_ONLY(_is_mapped = true;) 78 NOT_CDS_JAVA_HEAP_RETURN; 79 } 80 static bool is_mapped() { 81 CDS_JAVA_HEAP_ONLY(return _is_mapped;) 82 NOT_CDS_JAVA_HEAP_RETURN_(false); 83 } 84 85 // NarrowOops stored in the CDS archive may use a different encoding scheme 86 // than CompressedOops::{base,shift} -- see FileMapInfo::map_heap_region_impl. 87 // To decode them, do not use CompressedOops::decode_not_null. Use this 88 // function instead. 89 inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr); 90 91 // More efficient version, but works only when ArchiveHeap is mapped. 92 inline static oop decode_from_mapped_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr); 93 94 static void patch_compressed_embedded_pointers(BitMapView bm, 95 FileMapInfo* info, 96 MemRegion region) NOT_CDS_JAVA_HEAP_RETURN; 97 98 static void patch_embedded_pointers(FileMapInfo* info, 99 MemRegion region, address oopmap, 100 size_t oopmap_size_in_bits) NOT_CDS_JAVA_HEAP_RETURN; 101 102 static void fixup_region() NOT_CDS_JAVA_HEAP_RETURN; 103 104 #if INCLUDE_CDS_JAVA_HEAP 105 static void init_mapped_heap_info(address mapped_heap_bottom, ptrdiff_t delta, int dumptime_oop_shift); 106 private: 107 static bool _is_mapped; 108 static bool _is_loaded; 109 110 // Support for loaded archived heap. These are cached values from 111 // LoadedArchiveHeapRegion's. 112 static uintptr_t _dumptime_base; 113 static uintptr_t _dumptime_top; 114 static intx _runtime_offset; 115 116 static uintptr_t _loaded_heap_bottom; 117 static uintptr_t _loaded_heap_top; 118 static bool _loading_failed; 119 120 // UseCompressedOops only: Used by decode_from_archive 121 static bool _narrow_oop_base_initialized; 122 static address _narrow_oop_base; 123 static int _narrow_oop_shift; 124 125 // is_mapped() only: the mapped address of each region is offset by this amount from 126 // their requested address. 127 static uintptr_t _mapped_heap_bottom; 128 static ptrdiff_t _mapped_heap_delta; 129 static bool _mapped_heap_relocation_initialized; 130 131 static void init_narrow_oop_decoding(address base, int shift); 132 static bool init_loaded_region(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_region, 133 MemRegion& archive_space); 134 static bool load_heap_region_impl(FileMapInfo* mapinfo, LoadedArchiveHeapRegion* loaded_region, uintptr_t buffer); 135 static void init_loaded_heap_relocation(LoadedArchiveHeapRegion* reloc_info); 136 static void patch_native_pointers(); 137 static void finish_loaded_heap(); 138 static void verify_loaded_heap(); 139 static void fill_failed_loaded_heap(); 140 141 static bool is_in_loaded_heap(uintptr_t o) { 142 return (_loaded_heap_bottom <= o && o < _loaded_heap_top); 143 } 144 145 template<bool IS_MAPPED> 146 inline static oop decode_from_archive_impl(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(nullptr); 147 148 class PatchLoadedRegionPointers; 149 class PatchUncompressedLoadedRegionPointers; 150 151 public: 152 153 static bool load_heap_region(FileMapInfo* mapinfo); 154 static void assert_in_loaded_heap(uintptr_t o) { 155 assert(is_in_loaded_heap(o), "must be"); 156 } 157 #endif // INCLUDE_CDS_JAVA_HEAP 158 159 }; 160 161 #endif // SHARE_CDS_ARCHIVEHEAPLOADER_HPP