1 /*
   2  * Copyright (c) 1997, 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 
  25 #ifndef SHARE_VM_RUNTIME_VM_VERSION_HPP
  26 #define SHARE_VM_RUNTIME_VM_VERSION_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "utilities/ostream.hpp"
  30 
  31 // VM_Version provides information about the VM.
  32 
  33 class Abstract_VM_Version: AllStatic {
  34   friend class VMStructs;
  35   friend class JVMCIVMStructs;
  36 
  37  protected:
  38   static const char*  _s_vm_release;
  39   static const char*  _s_internal_vm_info_string;
  40 
  41   // CPU feature flags.
  42   static uint64_t _features;
  43   static const char* _features_string;
  44 
  45   // These are set by machine-dependent initializations
  46   static bool         _supports_cx8;
  47   static bool         _supports_atomic_getset4;
  48   static bool         _supports_atomic_getset8;
  49   static bool         _supports_atomic_getadd4;
  50   static bool         _supports_atomic_getadd8;
  51   static unsigned int _logical_processors_per_package;
  52   static unsigned int _L1_data_cache_line_size;
  53   static int          _vm_major_version;
  54   static int          _vm_minor_version;
  55   static int          _vm_security_version;
  56   static int          _vm_patch_version;
  57   static int          _vm_build_number;
  58   static unsigned int _parallel_worker_threads;
  59   static bool         _parallel_worker_threads_initialized;
  60   static int          _reserve_for_allocation_prefetch;
  61 
  62   static unsigned int nof_parallel_worker_threads(unsigned int num,
  63                                                   unsigned int dem,
  64                                                   unsigned int switch_pt);
  65  public:
  66   // Called as part of the runtime services initialization which is
  67   // called from the management module initialization (via init_globals())
  68   // after argument parsing and attaching of the main thread has
  69   // occurred.  Examines a variety of the hardware capabilities of
  70   // the platform to determine which features can be used to execute the
  71   // program.
  72   static void initialize();
  73 
  74   // This allows for early initialization of VM_Version information
  75   // that may be needed later in the initialization sequence but before
  76   // full VM_Version initialization is possible. It can not depend on any
  77   // other part of the VM being initialized when called. Platforms that
  78   // need to specialize this define VM_Version::early_initialize().
  79   static void early_initialize() { }
  80 
  81   // Called to initialize VM variables needing initialization
  82   // after command line parsing. Platforms that need to specialize
  83   // this should define VM_Version::init_before_ergo().
  84   static void init_before_ergo() {}
  85 
  86   // Name
  87   static const char* vm_name();
  88   // Vendor
  89   static const char* vm_vendor();
  90   // VM version information string printed by launcher (java -version)
  91   static const char* vm_info_string();
  92   static const char* vm_release();
  93   static const char* vm_platform_string();
  94   static const char* vm_build_user();
  95 
  96   static int vm_major_version()               { return _vm_major_version; }
  97   static int vm_minor_version()               { return _vm_minor_version; }
  98   static int vm_security_version()            { return _vm_security_version; }
  99   static int vm_patch_version()               { return _vm_patch_version; }
 100   static int vm_build_number()                { return _vm_build_number; }
 101 
 102   // Gets the jvm_version_info.jvm_version defined in jvm.h
 103   static unsigned int jvm_version();
 104 
 105   // Internal version providing additional build information
 106   static const char* internal_vm_info_string();
 107   static const char* jre_release_version();
 108   static const char* jdk_debug_level();
 109   static const char* printable_jdk_debug_level();
 110 
 111   static uint64_t features() {
 112     return _features;
 113   }
 114 
 115   static const char* features_string() {
 116     return _features_string;
 117   }
 118 
 119   // does HW support an 8-byte compare-exchange operation?
 120   static bool supports_cx8()  {
 121 #ifdef SUPPORTS_NATIVE_CX8
 122     return true;
 123 #else
 124     return _supports_cx8;
 125 #endif
 126   }
 127   // does HW support atomic get-and-set or atomic get-and-add?  Used
 128   // to guide intrinsification decisions for Unsafe atomic ops
 129   static bool supports_atomic_getset4()  {return _supports_atomic_getset4;}
 130   static bool supports_atomic_getset8()  {return _supports_atomic_getset8;}
 131   static bool supports_atomic_getadd4()  {return _supports_atomic_getadd4;}
 132   static bool supports_atomic_getadd8()  {return _supports_atomic_getadd8;}
 133 
 134   static unsigned int logical_processors_per_package() {
 135     return _logical_processors_per_package;
 136   }
 137 
 138   static unsigned int L1_data_cache_line_size() {
 139     return _L1_data_cache_line_size;
 140   }
 141 
 142   // Need a space at the end of TLAB for prefetch instructions
 143   // which may fault when accessing memory outside of heap.
 144   static int reserve_for_allocation_prefetch() {
 145     return _reserve_for_allocation_prefetch;
 146   }
 147 
 148   // ARCH specific policy for the BiasedLocking
 149   static bool use_biased_locking()  { return true; }
 150 
 151   // Number of page sizes efficiently supported by the hardware.  Most chips now
 152   // support two sizes, thus this default implementation.  Processor-specific
 153   // subclasses should define new versions to hide this one as needed.  Note
 154   // that the O/S may support more sizes, but at most this many are used.
 155   static uint page_size_count() { return 2; }
 156 
 157   // Returns the number of parallel threads to be used for VM
 158   // work.  If that number has not been calculated, do so and
 159   // save it.  Returns ParallelGCThreads if it is set on the
 160   // command line.
 161   static unsigned int parallel_worker_threads();
 162   // Calculates and returns the number of parallel threads.  May
 163   // be VM version specific.
 164   static unsigned int calc_parallel_worker_threads();
 165  
 166   // Does this compiler support intrinsification 
 167   // of java.lang.Runtime.onSpinWait() 
 168   static bool supports_on_spin_wait() { return false; }
 169 };
 170 
 171 #ifdef TARGET_ARCH_x86
 172 # include "vm_version_x86.hpp"
 173 #endif
 174 #ifdef TARGET_ARCH_sparc
 175 # include "vm_version_sparc.hpp"
 176 #endif
 177 #ifdef TARGET_ARCH_zero
 178 # include "vm_version_zero.hpp"
 179 #endif
 180 #ifdef TARGET_ARCH_arm
 181 # include "vm_version_arm.hpp"
 182 #endif
 183 #ifdef TARGET_ARCH_ppc
 184 # include "vm_version_ppc.hpp"
 185 #endif
 186 
 187 #endif // SHARE_VM_RUNTIME_VM_VERSION_HPP