1 /*
  2  * Copyright (c) 1997, 2024, 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_RUNTIME_ABSTRACT_VM_VERSION_HPP
 26 #define SHARE_RUNTIME_ABSTRACT_VM_VERSION_HPP
 27 
 28 #include "memory/allStatic.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 enum class vmIntrinsicID;
 46 
 47 // Abstract_VM_Version provides information about the VM.
 48 
 49 class Abstract_VM_Version: AllStatic {
 50   friend class VMStructs;
 51   friend class JVMCIVMStructs;
 52 
 53  protected:
 54   static const char*  _s_vm_release;
 55   static const char*  _s_internal_vm_info_string;
 56 
 57   // CPU feature flags.
 58   static uint64_t _features;
 59   static const char* _features_string;
 60 
 61   // These are set by machine-dependent initializations
 62   static bool         _supports_cx8;
 63   static bool         _supports_atomic_getset4;
 64   static bool         _supports_atomic_getset8;
 65   static bool         _supports_atomic_getadd4;
 66   static bool         _supports_atomic_getadd8;
 67   static unsigned int _logical_processors_per_package;
 68   static unsigned int _L1_data_cache_line_size;
 69   static int          _vm_major_version;
 70   static int          _vm_minor_version;
 71   static int          _vm_security_version;
 72   static int          _vm_patch_version;
 73   static int          _vm_build_number;
 74   static unsigned int _data_cache_line_flush_size;
 75 
 76  public:
 77 
 78   static VirtualizationType _detected_virtualization;
 79 
 80   // Called as part of the runtime services initialization which is
 81   // called from the management module initialization (via init_globals())
 82   // after argument parsing and attaching of the main thread has
 83   // occurred.  Examines a variety of the hardware capabilities of
 84   // the platform to determine which features can be used to execute the
 85   // program.
 86   static void initialize() { }
 87 
 88   // This allows for early initialization of VM_Version information
 89   // that may be needed later in the initialization sequence but before
 90   // full VM_Version initialization is possible. It can not depend on any
 91   // other part of the VM being initialized when called. Platforms that
 92   // need to specialize this define VM_Version::early_initialize().
 93   static void early_initialize() { }
 94 
 95   // Called to initialize VM variables needing initialization
 96   // after command line parsing. Platforms that need to specialize
 97   // this should define VM_Version::init_before_ergo().
 98   static void init_before_ergo() {}
 99 
100   // Name
101   static const char* vm_name();
102   // Vendor
103   static const char* vm_vendor();
104   // VM version information string printed by launcher (java -version)
105   static const char* vm_info_string();
106   static const char* vm_release();
107   static const char* vm_platform_string();
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* jdk_debug_level();
121   static const char* printable_jdk_debug_level();
122 
123   static uint64_t features()           { return _features; }
124   static const char* features_string() { return _features_string; }
125   static void insert_features_names(char* buf, size_t buflen, const char* features_names[]);
126 
127   static VirtualizationType get_detected_virtualization() {
128     return _detected_virtualization;
129   }
130 
131   // platforms that need to specialize this
132   // define VM_Version::print_platform_virtualization_info()
133   static void print_platform_virtualization_info(outputStream*) { }
134 
135   // does HW support an 8-byte compare-exchange operation?
136   static bool supports_cx8()  {
137 #ifdef SUPPORTS_NATIVE_CX8
138     return true;
139 #else
140     return _supports_cx8;
141 #endif
142   }
143   // does HW support atomic get-and-set or atomic get-and-add?  Used
144   // to guide intrinsification decisions for Unsafe atomic ops
145   static bool supports_atomic_getset4()  {return _supports_atomic_getset4;}
146   static bool supports_atomic_getset8()  {return _supports_atomic_getset8;}
147   static bool supports_atomic_getadd4()  {return _supports_atomic_getadd4;}
148   static bool supports_atomic_getadd8()  {return _supports_atomic_getadd8;}
149 
150   static unsigned int logical_processors_per_package() {
151     return _logical_processors_per_package;
152   }
153 
154   static unsigned int L1_data_cache_line_size() {
155     return _L1_data_cache_line_size;
156   }
157 
158   // the size in bytes of a data cache line flushed by a flush
159   // operation which should be a power of two or zero if cache line
160   // writeback is not supported by the current os_cpu combination
161   static unsigned int data_cache_line_flush_size() {
162     return _data_cache_line_flush_size;
163   }
164 
165   // returns true if and only if cache line writeback is supported
166   static bool supports_data_cache_line_flush() {
167     return _data_cache_line_flush_size != 0;
168   }
169 
170   // Denominator for computing default ParallelGCThreads for machines with
171   // a large number of cores.
172   static uint parallel_worker_threads_denominator() { return 8; }
173 
174   // Does this CPU support spin wait instruction?
175   static bool supports_on_spin_wait() { return false; }
176 
177   // Does platform support fast class initialization checks for static methods?
178   static bool supports_fast_class_init_checks() { return false; }
179 
180   // Does platform support stack watermark barriers for concurrent stack processing?
181   constexpr static bool supports_stack_watermark_barrier() { return false; }
182 
183   // Is recursive lightweight locking implemented for this platform?
184   constexpr static bool supports_recursive_lightweight_locking() { return false; }
185 
186   // Does platform support float16 instructions?
187   static bool supports_float16() { return false; }
188 
189   // Does this CPU support this intrinsic?
190   static bool is_intrinsic_supported(vmIntrinsicID id) { return true; }
191 
192   static bool print_matching_lines_from_file(const char* filename, outputStream* st, const char* keywords_to_match[]);
193 
194  protected:
195   // VM_Version statics
196   static const size_t      CPU_TYPE_DESC_BUF_SIZE = 256;
197   static const size_t      CPU_DETAILED_DESC_BUF_SIZE = 4096;
198 
199   static int   _no_of_threads;
200   static int   _no_of_cores;
201   static int   _no_of_sockets;
202   static bool  _initialized;
203   static char  _cpu_name[CPU_TYPE_DESC_BUF_SIZE];
204   static char  _cpu_desc[CPU_DETAILED_DESC_BUF_SIZE];
205 
206  public:
207   static int number_of_threads(void);
208   static int number_of_cores(void);
209   static int number_of_sockets(void);
210 
211   static const char* cpu_name(void);
212   static const char* cpu_description(void);
213 };
214 
215 #endif // SHARE_RUNTIME_ABSTRACT_VM_VERSION_HPP
--- EOF ---