1 /* 2 * Copyright (c) 1997, 2014, 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 protected: 35 friend class VMStructs; 36 static const char* _s_vm_release; 37 static const char* _s_internal_vm_info_string; 38 // These are set by machine-dependent initializations 39 static bool _supports_cx8; 40 static bool _supports_atomic_getset4; 41 static bool _supports_atomic_getset8; 42 static bool _supports_atomic_getadd4; 43 static bool _supports_atomic_getadd8; 44 static unsigned int _logical_processors_per_package; 45 static unsigned int _L1_data_cache_line_size; 46 static int _vm_major_version; 47 static int _vm_minor_version; 48 static int _vm_build_number; 49 static bool _initialized; 50 static int _parallel_worker_threads; 51 static bool _parallel_worker_threads_initialized; 52 static int _reserve_for_allocation_prefetch; 53 54 static unsigned int nof_parallel_worker_threads(unsigned int num, 55 unsigned int dem, 56 unsigned int switch_pt); 57 public: 58 // Called as part of the runtime services initialization which is 59 // called from the management module initialization (via init_globals()) 60 // after argument parsing and attaching of the main thread has 61 // occurred. Examines a variety of the hardware capabilities of 62 // the platform to determine which features can be used to execute the 63 // program. 64 static void initialize(); 65 66 // This allows for early initialization of VM_Version information 67 // that may be needed later in the initialization sequence but before 68 // full VM_Version initialization is possible. It can not depend on any 69 // other part of the VM being initialized when called. Platforms that 70 // need to specialize this define VM_Version::early_initialize(). early_initialize()71 static void early_initialize() { } 72 73 // Called to initialize VM variables needing initialization 74 // after command line parsing. Platforms that need to specialize 75 // this should define VM_Version::init_before_ergo(). init_before_ergo()76 static void init_before_ergo() {} 77 78 // Name 79 static const char* vm_name(); 80 // Vendor 81 static const char* vm_vendor(); 82 // VM version information string printed by launcher (java -version) 83 static const char* vm_info_string(); 84 static const char* vm_release(); 85 static const char* vm_platform_string(); 86 static const char* vm_build_user(); 87 vm_major_version()88 static int vm_major_version() { assert(_initialized, "not initialized"); return _vm_major_version; } vm_minor_version()89 static int vm_minor_version() { assert(_initialized, "not initialized"); return _vm_minor_version; } vm_build_number()90 static int vm_build_number() { assert(_initialized, "not initialized"); return _vm_build_number; } 91 92 // Gets the jvm_version_info.jvm_version defined in jvm.h 93 static unsigned int jvm_version(); 94 95 // Internal version providing additional build information 96 static const char* internal_vm_info_string(); 97 static const char* jre_release_version(); 98 99 // does HW support an 8-byte compare-exchange operation? supports_cx8()100 static bool supports_cx8() { 101 assert(_initialized, "not initialized"); 102 #ifdef SUPPORTS_NATIVE_CX8 103 return true; 104 #else 105 return _supports_cx8; 106 #endif 107 } 108 // does HW support atomic get-and-set or atomic get-and-add? Used 109 // to guide intrinsification decisions for Unsafe atomic ops supports_atomic_getset4()110 static bool supports_atomic_getset4() { assert(_initialized, "not initialized"); return _supports_atomic_getset4;} supports_atomic_getset8()111 static bool supports_atomic_getset8() { assert(_initialized, "not initialized"); return _supports_atomic_getset8;} supports_atomic_getadd4()112 static bool supports_atomic_getadd4() { assert(_initialized, "not initialized"); return _supports_atomic_getadd4;} supports_atomic_getadd8()113 static bool supports_atomic_getadd8() { assert(_initialized, "not initialized"); return _supports_atomic_getadd8;} 114 logical_processors_per_package()115 static unsigned int logical_processors_per_package() { 116 return _logical_processors_per_package; 117 } 118 L1_data_cache_line_size()119 static unsigned int L1_data_cache_line_size() { 120 return _L1_data_cache_line_size; 121 } 122 123 // Need a space at the end of TLAB for prefetch instructions 124 // which may fault when accessing memory outside of heap. reserve_for_allocation_prefetch()125 static int reserve_for_allocation_prefetch() { 126 return _reserve_for_allocation_prefetch; 127 } 128 129 // ARCH specific policy for the BiasedLocking use_biased_locking()130 static bool use_biased_locking() { return true; } 131 132 // Number of page sizes efficiently supported by the hardware. Most chips now 133 // support two sizes, thus this default implementation. Processor-specific 134 // subclasses should define new versions to hide this one as needed. Note 135 // that the O/S may support more sizes, but at most this many are used. page_size_count()136 static uint page_size_count() { return 2; } 137 138 // Returns the number of parallel threads to be used for VM 139 // work. If that number has not been calculated, do so and 140 // save it. Returns ParallelGCThreads if it is set on the 141 // command line. 142 static unsigned int parallel_worker_threads(); 143 // Calculates and returns the number of parallel threads. May 144 // be VM version specific. 145 static unsigned int calc_parallel_worker_threads(); 146 }; 147 148 #endif // SHARE_VM_RUNTIME_VM_VERSION_HPP 149