1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
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  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  *
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 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
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 20  * or visit www.oracle.com if you need additional information or have any
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 24 
 25 #ifndef SHARE_RUNTIME_ABSTRACT_VM_VERSION_HPP
 26 #define SHARE_RUNTIME_ABSTRACT_VM_VERSION_HPP
 27 
 28 #include "memory/allocation.hpp"  // For declaration of class AllStatic
 29 #include "utilities/globalDefinitions.hpp"
 30 
 31 typedef enum {
 32   NoDetectedVirtualization,
 33   XenHVM,
 34   XenPVHVM, // mix-mode on Linux aarch64
 35   KVM,
 36   VMWare,
 37   HyperV,
 38   HyperVRole,
 39   PowerVM, // on AIX or Linux ppc64(le)
 40   PowerFullPartitionMode, // on Linux ppc64(le)
 41   PowerKVM
 42 } VirtualizationType;
 43 
 44 class outputStream;
 45 
 46 // Abstract_VM_Version provides information about the VM.
 47 
 48 class Abstract_VM_Version: AllStatic {
 49   friend class VMStructs;
 50   friend class JVMCIVMStructs;
 51 
 52  protected:
 53   static const char*  _s_vm_release;
 54   static const char*  _s_internal_vm_info_string;
 55 
 56   // CPU feature flags.
 57   static uint64_t _features;
 58   static const char* _features_string;
 59 
 60   // These are set by machine-dependent initializations
 61   static bool         _supports_cx8;
 62   static bool         _supports_atomic_getset4;
 63   static bool         _supports_atomic_getset8;
 64   static bool         _supports_atomic_getadd4;
 65   static bool         _supports_atomic_getadd8;
 66   static unsigned int _logical_processors_per_package;
 67   static unsigned int _L1_data_cache_line_size;
 68   static int          _vm_major_version;
 69   static int          _vm_minor_version;
 70   static int          _vm_security_version;
 71   static int          _vm_patch_version;
 72   static int          _vm_build_number;
 73   static unsigned int _data_cache_line_flush_size;
 74 
 75  public:
 76 
 77   static VirtualizationType _detected_virtualization;
 78 
 79   // Called as part of the runtime services initialization which is
 80   // called from the management module initialization (via init_globals())
 81   // after argument parsing and attaching of the main thread has
 82   // occurred.  Examines a variety of the hardware capabilities of
 83   // the platform to determine which features can be used to execute the
 84   // program.
 85   static void initialize() { }
 86 
 87   // This allows for early initialization of VM_Version information
 88   // that may be needed later in the initialization sequence but before
 89   // full VM_Version initialization is possible. It can not depend on any
 90   // other part of the VM being initialized when called. Platforms that
 91   // need to specialize this define VM_Version::early_initialize().
 92   static void early_initialize() { }
 93 
 94   // Called to initialize VM variables needing initialization
 95   // after command line parsing. Platforms that need to specialize
 96   // this should define VM_Version::init_before_ergo().
 97   static void init_before_ergo() {}
 98 
 99   // Name
100   static const char* vm_name();
101   // Vendor
102   static const char* vm_vendor();
103   // VM version information string printed by launcher (java -version)
104   static const char* vm_info_string();
105   static const char* vm_release();
106   static const char* vm_platform_string();
107   static const char* vm_build_user();
108 
109   static int vm_major_version()               { return _vm_major_version; }
110   static int vm_minor_version()               { return _vm_minor_version; }
111   static int vm_security_version()            { return _vm_security_version; }
112   static int vm_patch_version()               { return _vm_patch_version; }
113   static int vm_build_number()                { return _vm_build_number; }
114 
115   // Gets the jvm_version_info.jvm_version
116   static unsigned int jvm_version();
117 
118   // Internal version providing additional build information
119   static const char* internal_vm_info_string();
120   static const char* jre_release_version();
121   static const char* jdk_debug_level();
122   static const char* printable_jdk_debug_level();
123 
124   static uint64_t features()           { return _features; }
125   static const char* features_string() { return _features_string; }
126   static void insert_features_names(char* buf, size_t buflen, const char* features_names[]);
127 
128   static VirtualizationType get_detected_virtualization() {
129     return _detected_virtualization;
130   }
131 
132   // platforms that need to specialize this
133   // define VM_Version::print_platform_virtualization_info()
134   static void print_platform_virtualization_info(outputStream*) { }
135 
136   // does HW support an 8-byte compare-exchange operation?
137   static bool supports_cx8()  {
138 #ifdef SUPPORTS_NATIVE_CX8
139     return true;
140 #else
141     return _supports_cx8;
142 #endif
143   }
144   // does HW support atomic get-and-set or atomic get-and-add?  Used
145   // to guide intrinsification decisions for Unsafe atomic ops
146   static bool supports_atomic_getset4()  {return _supports_atomic_getset4;}
147   static bool supports_atomic_getset8()  {return _supports_atomic_getset8;}
148   static bool supports_atomic_getadd4()  {return _supports_atomic_getadd4;}
149   static bool supports_atomic_getadd8()  {return _supports_atomic_getadd8;}
150 
151   static unsigned int logical_processors_per_package() {
152     return _logical_processors_per_package;
153   }
154 
155   static unsigned int L1_data_cache_line_size() {
156     return _L1_data_cache_line_size;
157   }
158 
159   // the size in bytes of a data cache line flushed by a flush
160   // operation which should be a power of two or zero if cache line
161   // writeback is not supported by the current os_cpu combination
162   static unsigned int data_cache_line_flush_size() {
163     return _data_cache_line_flush_size;
164   }
165 
166   // returns true if and only if cache line writeback is supported
167   static bool supports_data_cache_line_flush() {
168     return _data_cache_line_flush_size != 0;
169   }
170 
171   // ARCH specific policy for the BiasedLocking
172   static bool use_biased_locking()  { return true; }
173 
174   // Number of page sizes efficiently supported by the hardware.  Most chips now
175   // support two sizes, thus this default implementation.  Processor-specific
176   // subclasses should define new versions to hide this one as needed.  Note
177   // that the O/S may support more sizes, but at most this many are used.
178   static uint page_size_count() { return 2; }
179 
180   // Denominator for computing default ParallelGCThreads for machines with
181   // a large number of cores.
182   static uint parallel_worker_threads_denominator() { return 8; }
183 
184   // Does this CPU support spin wait instruction?
185   static bool supports_on_spin_wait() { return false; }
186 
187   // Does platform support fast class initialization checks for static methods?
188   static bool supports_fast_class_init_checks() { return false; }
189 
190   // Does platform support stack watermark barriers for concurrent stack processing?
191   constexpr static bool supports_stack_watermark_barrier() { return false; }
192 
193   // Is recursive lightweight locking implemented for this platform?
194   constexpr static bool supports_recursive_lightweight_locking() { return false; }
195 
196   static bool print_matching_lines_from_file(const char* filename, outputStream* st, const char* keywords_to_match[]);
197 };
198 
199 #endif // SHARE_RUNTIME_ABSTRACT_VM_VERSION_HPP