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.
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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
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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().
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().
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
88 static int vm_major_version() { assert(_initialized, "not initialized"); return _vm_major_version; }
89 static int vm_minor_version() { assert(_initialized, "not initialized"); return _vm_minor_version; }
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?
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
110 static bool supports_atomic_getset4() { assert(_initialized, "not initialized"); return _supports_atomic_getset4;}
111 static bool supports_atomic_getset8() { assert(_initialized, "not initialized"); return _supports_atomic_getset8;}
112 static bool supports_atomic_getadd4() { assert(_initialized, "not initialized"); return _supports_atomic_getadd4;}
113 static bool supports_atomic_getadd8() { assert(_initialized, "not initialized"); return _supports_atomic_getadd8;}
114
115 static unsigned int logical_processors_per_package() {
116 return _logical_processors_per_package;
117 }
118
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.
125 static int reserve_for_allocation_prefetch() {
126 return _reserve_for_allocation_prefetch;
127 }
128
129 // ARCH specific policy for the BiasedLocking
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.
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