1 /*
   2  * Copyright (c) 2012, 2016, 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 #define LargeSharedArchiveSize    (300*M)
  34 #define HugeSharedArchiveSize     (800*M)
  35 #define ReadOnlyRegionPercentage  0.39
  36 #define ReadWriteRegionPercentage 0.50
  37 #define MiscDataRegionPercentage  0.09
  38 #define MiscCodeRegionPercentage  0.02
  39 #define LargeThresholdClassCount  5000
  40 #define HugeThresholdClassCount   40000
  41 
  42 #define SET_ESTIMATED_SIZE(type, region)                              \
  43   Shared ##region## Size  = FLAG_IS_DEFAULT(Shared ##region## Size) ? \
  44     (uintx)(type ## SharedArchiveSize *  region ## RegionPercentage) : Shared ## region ## Size
  45 
  46 class FileMapInfo;
  47 
  48 // Class Data Sharing Support
  49 class MetaspaceShared : AllStatic {
  50 
  51   // CDS support
  52   static ReservedSpace* _shared_rs;
  53   static int _max_alignment;
  54   static bool _link_classes_made_progress;
  55   static bool _check_classes_made_progress;
  56   static bool _has_error_classes;
  57   static bool _archive_loading_failed;
  58   static bool _remapped_readwrite;
  59  public:
  60   enum {
  61     vtbl_list_size         = 17,   // number of entries in the shared space vtable list.
  62     num_virtuals           = 200,  // maximum number of virtual functions
  63                                    // If virtual functions are added to Metadata,
  64                                    // this number needs to be increased.  Also,
  65                                    // SharedMiscCodeSize will need to be increased.
  66                                    // The following 2 sizes were based on
  67                                    // MetaspaceShared::generate_vtable_methods()
  68     vtbl_method_size       = 16,   // conservative size of the mov1 and jmp instructions
  69                                    // for the x64 platform
  70     vtbl_common_code_size  = (1*K) // conservative size of the "common_code" for the x64 platform
  71   };
  72 
  73   enum {
  74     ro = 0,  // read-only shared space in the heap
  75     rw = 1,  // read-write shared space in the heap
  76     md = 2,  // miscellaneous data for initializing tables, etc.
  77     mc = 3,  // miscellaneous code - vtable replacement.
  78     n_regions = 4
  79   };
  80 
  81   // Accessor functions to save shared space created for metadata, which has
  82   // extra space allocated at the end for miscellaneous data and code.
  83   static void set_max_alignment(int alignment) {
  84     CDS_ONLY(_max_alignment = alignment);
  85   }
  86 
  87   static int max_alignment() {
  88     CDS_ONLY(return _max_alignment);
  89     NOT_CDS(return 0);
  90   }
  91 
  92   static void prepare_for_dumping() NOT_CDS_RETURN;
  93   static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
  94   static int preload_and_dump(const char * class_list_path,
  95                               GrowableArray<Klass*>* class_promote_order,
  96                               TRAPS) NOT_CDS_RETURN;
  97 
  98   static ReservedSpace* shared_rs() {
  99     CDS_ONLY(return _shared_rs);
 100     NOT_CDS(return NULL);
 101   }
 102 
 103   static void set_shared_rs(ReservedSpace* rs) {
 104     CDS_ONLY(_shared_rs = rs;)
 105   }
 106 
 107   static void set_archive_loading_failed() {
 108     _archive_loading_failed = true;
 109   }
 110   static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
 111   static void initialize_shared_spaces() NOT_CDS_RETURN;
 112 
 113   // Return true if given address is in the mapped shared space.
 114   static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);
 115 
 116   static void generate_vtable_methods(void** vtbl_list,
 117                                       void** vtable,
 118                                       char** md_top, char* md_end,
 119                                       char** mc_top, char* mc_end);
 120   static void serialize(SerializeClosure* sc);
 121 
 122   // JVM/TI RedefineClasses() support:
 123   // Remap the shared readonly space to shared readwrite, private if
 124   // sharing is enabled. Simply returns true if sharing is not enabled
 125   // or if the remapping has already been done by a prior call.
 126   static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
 127   static bool remapped_readwrite() {
 128     CDS_ONLY(return _remapped_readwrite);
 129     NOT_CDS(return false);
 130   }
 131 
 132   static void print_shared_spaces();
 133 
 134   static bool try_link_class(InstanceKlass* ik, TRAPS);
 135   static void link_one_shared_class(Klass* obj, TRAPS);
 136   static void check_one_shared_class(Klass* obj);
 137   static void link_and_cleanup_shared_classes(TRAPS);
 138 
 139   static int count_class(const char* classlist_file);
 140   static void estimate_regions_size() NOT_CDS_RETURN;
 141 };
 142 #endif // SHARE_VM_MEMORY_METASPACE_SHARED_HPP