1 /* 2 * Copyright (c) 2012, 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 #ifndef SHARE_VM_MEMORY_METASPACE_SHARED_HPP 25 #define SHARE_VM_MEMORY_METASPACE_SHARED_HPP 26 27 #include "memory/allocation.hpp" 28 #include "memory/memRegion.hpp" 29 #include "runtime/virtualspace.hpp" 30 #include "utilities/exceptions.hpp" 31 #include "utilities/macros.hpp" 32 33 class FileMapInfo; 34 35 // Class Data Sharing Support 36 class MetaspaceShared : AllStatic { 37 38 // CDS support 39 static ReservedSpace* _shared_rs; 40 static int _max_alignment; 41 42 public: 43 enum { 44 vtbl_list_size = 17, // number of entries in the shared space vtable list. 45 num_virtuals = 200 // maximum number of virtual functions 46 // If virtual functions are added to Metadata, 47 // this number needs to be increased. Also, 48 // SharedMiscCodeSize will need to be increased. 49 }; 50 51 enum { 52 ro = 0, // read-only shared space in the heap 53 rw = 1, // read-write shared space in the heap 54 md = 2, // miscellaneous data for initializing tables, etc. 55 mc = 3, // miscellaneous code - vtable replacement. 56 n_regions = 4 57 }; 58 59 static void set_max_alignment(int alignment) KERNEL_RETURN; 60 static int max_alignment() KERNEL_RETURN_(0); 61 62 static void preload_and_dump(TRAPS) KERNEL_RETURN; 63 static ReservedSpace* shared_rs(); 64 static void set_shared_rs(ReservedSpace* rs) KERNEL_RETURN; 65 66 static bool map_shared_spaces(FileMapInfo* mapinfo) KERNEL_RETURN_(false); 67 static void initialize_shared_spaces() KERNEL_RETURN; 68 69 // Return true if given address is in the mapped shared space. 70 static bool is_in_shared_space(const void* p) KERNEL_RETURN_(false); 71 72 static void generate_vtable_methods(void** vtbl_list, 73 void** vtable, 74 char** md_top, char* md_end, 75 char** mc_top, char* mc_end); 76 static void serialize(SerializeClosure* sc); 77 78 // JVM/TI RedefineClasses() support: 79 // Remap the shared readonly space to shared readwrite, private if 80 // sharing is enabled. Simply returns true if sharing is not enabled 81 // or if the remapping has already been done by a prior call. 82 static bool remap_shared_readonly_as_readwrite() KERNEL_RETURN_(true); 83 84 static void print_shared_spaces(); 85 }; 86 #endif // SHARE_VM_MEMORY_METASPACE_SHARED_HPP