/*

 * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 *

 */

#ifndef SHARE_VM_MEMORY_METASPACESHARED_HPP

#define SHARE_VM_MEMORY_METASPACESHARED_HPP

#include "classfile/compactHashtable.hpp"

#include "memory/allocation.hpp"

#include "memory/memRegion.hpp"

#include "memory/virtualspace.hpp"

#include "utilities/exceptions.hpp"

#include "utilities/macros.hpp"

#define DEFAULT_VTBL_LIST_SIZE          (17)  // number of entries in the shared space vtable list.

#define DEFAULT_VTBL_VIRTUALS_COUNT     (200) // maximum number of virtual functions

// If virtual functions are added to Metadata,

// this number needs to be increased.  Also,

// SharedMiscCodeSize will need to be increased.

// The following 2 sizes were based on

// MetaspaceShared::generate_vtable_methods()

#define DEFAULT_VTBL_METHOD_SIZE        (16)  // conservative size of the mov1 and jmp instructions

// for the x64 platform

#define DEFAULT_VTBL_COMMON_CODE_SIZE   (1*K) // conservative size of the "common_code" for the x64 platform

#define DEFAULT_SHARED_READ_WRITE_SIZE  (NOT_LP64(12*M) LP64_ONLY(16*M))

#define MIN_SHARED_READ_WRITE_SIZE      (NOT_LP64(7*M) LP64_ONLY(12*M))

#define DEFAULT_SHARED_READ_ONLY_SIZE   (NOT_LP64(12*M) LP64_ONLY(16*M))

#define MIN_SHARED_READ_ONLY_SIZE       (NOT_LP64(8*M) LP64_ONLY(9*M))

// the MIN_SHARED_MISC_DATA_SIZE and MIN_SHARED_MISC_CODE_SIZE estimates are based on

// MetaspaceShared::generate_vtable_methods().

// The minimum size only accounts for the vtable methods. Any size less than the

// minimum required size would cause vm crash when allocating the vtable methods.

#define SHARED_MISC_SIZE_FOR(size)      (DEFAULT_VTBL_VIRTUALS_COUNT*DEFAULT_VTBL_LIST_SIZE*size)

#define DEFAULT_SHARED_MISC_DATA_SIZE   (NOT_LP64(2*M) LP64_ONLY(4*M))

#define MIN_SHARED_MISC_DATA_SIZE       (SHARED_MISC_SIZE_FOR(sizeof(void*)))

#define DEFAULT_SHARED_MISC_CODE_SIZE   (120*K)

#define MIN_SHARED_MISC_CODE_SIZE       (SHARED_MISC_SIZE_FOR(sizeof(void*))+SHARED_MISC_SIZE_FOR(DEFAULT_VTBL_METHOD_SIZE)+DEFAULT_VTBL_COMMON_CODE_SIZE)

#define DEFAULT_COMBINED_SIZE           (DEFAULT_SHARED_READ_WRITE_SIZE+DEFAULT_SHARED_READ_ONLY_SIZE+DEFAULT_SHARED_MISC_DATA_SIZE+DEFAULT_SHARED_MISC_CODE_SIZE)

// the max size is the MAX size (ie. 0x7FFFFFFF) - the total size of

// the other 3 sections - page size (to avoid overflow in case the final

// size will get aligned up on page size)

#define SHARED_PAGE                     ((size_t)os::vm_page_size())

#define MAX_SHARED_DELTA                (0x7FFFFFFF)

#define MAX_SHARED_READ_WRITE_SIZE      (MAX_SHARED_DELTA-(MIN_SHARED_READ_ONLY_SIZE+MIN_SHARED_MISC_DATA_SIZE+MIN_SHARED_MISC_CODE_SIZE)-SHARED_PAGE)

#define MAX_SHARED_READ_ONLY_SIZE       (MAX_SHARED_DELTA-(MIN_SHARED_READ_WRITE_SIZE+MIN_SHARED_MISC_DATA_SIZE+MIN_SHARED_MISC_CODE_SIZE)-SHARED_PAGE)

#define MAX_SHARED_MISC_DATA_SIZE       (MAX_SHARED_DELTA-(MIN_SHARED_READ_WRITE_SIZE+MIN_SHARED_READ_ONLY_SIZE+MIN_SHARED_MISC_CODE_SIZE)-SHARED_PAGE)

#define MAX_SHARED_MISC_CODE_SIZE       (MAX_SHARED_DELTA-(MIN_SHARED_READ_WRITE_SIZE+MIN_SHARED_READ_ONLY_SIZE+MIN_SHARED_MISC_DATA_SIZE)-SHARED_PAGE)

#define LargeSharedArchiveSize          (300*M)

#define HugeSharedArchiveSize           (800*M)

#define ReadOnlyRegionPercentage        0.4

#define ReadWriteRegionPercentage       0.55

#define MiscDataRegionPercentage        0.03

#define MiscCodeRegionPercentage        0.02

#define LargeThresholdClassCount        5000

#define HugeThresholdClassCount         40000

#define SET_ESTIMATED_SIZE(type, region)                              \

  Shared ##region## Size  = FLAG_IS_DEFAULT(Shared ##region## Size) ? \

    (uintx)(type ## SharedArchiveSize *  region ## RegionPercentage) : Shared ## region ## Size

class FileMapInfo;

class MetaspaceSharedStats VALUE_OBJ_CLASS_SPEC {

public:

  MetaspaceSharedStats() {

    memset(this, 0, sizeof(*this));

  }

  CompactHashtableStats symbol;

  CompactHashtableStats string;

};

class SharedMiscRegion VALUE_OBJ_CLASS_SPEC {

private:

  VirtualSpace _vs;

  char* _alloc_top;

  SharedSpaceType _space_type;

public:

  void initialize(ReservedSpace rs, size_t committed_byte_size,  SharedSpaceType space_type);

  VirtualSpace* virtual_space() {

    return &_vs;

  }

  char* low() const {

    return _vs.low();

  }

  char* alloc_top() const {

    return _alloc_top;

  }

  char* alloc(size_t num_bytes) NOT_CDS_RETURN_(NULL);

};

// Class Data Sharing Support

class MetaspaceShared : AllStatic {

  // CDS support

  static ReservedSpace* _shared_rs;

  static int _max_alignment;

  static MetaspaceSharedStats _stats;

  static bool _link_classes_made_progress;

  static bool _check_classes_made_progress;

  static bool _has_error_classes;

  static bool _archive_loading_failed;

  // Used only during dumping.

  static SharedMiscRegion _md;

  static SharedMiscRegion _mc;

 public:

  enum {

    vtbl_list_size         = DEFAULT_VTBL_LIST_SIZE,

    num_virtuals           = DEFAULT_VTBL_VIRTUALS_COUNT,

    vtbl_method_size       = DEFAULT_VTBL_METHOD_SIZE,

    vtbl_common_code_size  = DEFAULT_VTBL_COMMON_CODE_SIZE

  };

  enum {

    ro = 0,  // read-only shared space in the heap

    rw = 1,  // read-write shared space in the heap

    md = 2,  // miscellaneous data for initializing tables, etc.

    mc = 3,  // miscellaneous code - vtable replacement.

    max_strings = 2, // max number of string regions in string space

    num_non_strings = 4, // number of non-string regions

    first_string = num_non_strings, // index of first string region

    n_regions = max_strings + num_non_strings // total number of regions

  };

  // Accessor functions to save shared space created for metadata, which has

  // extra space allocated at the end for miscellaneous data and code.

  static void set_max_alignment(int alignment) {

    CDS_ONLY(_max_alignment = alignment);

  }

  static int max_alignment() {

    CDS_ONLY(return _max_alignment);

    NOT_CDS(return 0);

  }

  static void prepare_for_dumping() NOT_CDS_RETURN;

  static void preload_and_dump(TRAPS) NOT_CDS_RETURN;

  static int preload_and_dump(const char * class_list_path,

                              GrowableArray<Klass*>* class_promote_order,

                              TRAPS) NOT_CDS_RETURN_(0);

  static ReservedSpace* shared_rs() {

    CDS_ONLY(return _shared_rs);

    NOT_CDS(return NULL);

  }

  static void initialize_shared_rs(ReservedSpace* rs) NOT_CDS_RETURN;

  static void set_archive_loading_failed() {

    _archive_loading_failed = true;

  }

  static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);

  static void initialize_shared_spaces() NOT_CDS_RETURN;

  static void fixup_shared_string_regions() NOT_CDS_RETURN;

  // Return true if given address is in the mapped shared space.

  static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);

  static bool is_string_region(int idx) NOT_CDS_RETURN_(false);

  static void generate_vtable_methods(void** vtbl_list,

                                      void** vtable,

                                      char** md_top, char* md_end,

                                      char** mc_top, char* mc_end);

  static void serialize(SerializeClosure* sc);

  static MetaspaceSharedStats* stats() {

    return &_stats;

  }

  // JVM/TI RedefineClasses() support:

  // Remap the shared readonly space to shared readwrite, private if

  // sharing is enabled. Simply returns true if sharing is not enabled

  // or if the remapping has already been done by a prior call.

  static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);

  static void print_shared_spaces();

  static bool try_link_class(InstanceKlass* ik, TRAPS);

  static void link_one_shared_class(Klass* obj, TRAPS);

  static void check_one_shared_class(Klass* obj);

  static void link_and_cleanup_shared_classes(TRAPS);

  static int count_class(const char* classlist_file);

  static void estimate_regions_size() NOT_CDS_RETURN;

  // Allocate a block of memory from the "mc" or "md" regions.

  static char* misc_code_space_alloc(size_t num_bytes) {  return _mc.alloc(num_bytes); }

  static char* misc_data_space_alloc(size_t num_bytes) {  return _md.alloc(num_bytes); }

  static SharedMiscRegion* misc_code_region() {

    assert(DumpSharedSpaces, "used during dumping only");

    return &_mc;

  }

  static SharedMiscRegion* misc_data_region() {

    assert(DumpSharedSpaces, "used during dumping only");

    return &_md;

  }

};

#endif // SHARE_VM_MEMORY_METASPACESHARED_HPP