1 /*
2 * Copyright (c) 1997, 2013, 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 int _vm_major_version;
46 static int _vm_minor_version;
47 static int _vm_build_number;
48 static bool _initialized;
49 static int _parallel_worker_threads;
50 static bool _parallel_worker_threads_initialized;
51 static int _reserve_for_allocation_prefetch;
52
53 static unsigned int nof_parallel_worker_threads(unsigned int num,
54 unsigned int dem,
55 unsigned int switch_pt);
56 public:
57 static void initialize();
58
59 // This allows for early initialization of VM_Version information
60 // that may be needed later in the initialization sequence but before
61 // full VM_Version initialization is possible. It can not depend on any
62 // other part of the VM being initialized when called. Platforms that
63 // need to specialize this define VM_Version::early_initialize().
64 static void early_initialize() { }
65
66 // Name
67 static const char* vm_name();
68 // Vendor
69 static const char* vm_vendor();
70 // VM version information string printed by launcher (java -version)
71 static const char* vm_info_string();
72 static const char* vm_release();
73 static const char* vm_platform_string();
74 static const char* vm_build_user();
75
76 static int vm_major_version() { assert(_initialized, "not initialized"); return _vm_major_version; }
77 static int vm_minor_version() { assert(_initialized, "not initialized"); return _vm_minor_version; }
78 static int vm_build_number() { assert(_initialized, "not initialized"); return _vm_build_number; }
79
80 // Gets the jvm_version_info.jvm_version defined in jvm.h
81 static unsigned int jvm_version();
82
83 // Internal version providing additional build information
84 static const char* internal_vm_info_string();
85 static const char* jre_release_version();
86
87 // does HW support an 8-byte compare-exchange operation?
88 static bool supports_cx8() {
89 #ifdef SUPPORTS_NATIVE_CX8
90 return true;
91 #else
92 return _supports_cx8;
93 #endif
94 }
95 // does HW support atomic get-and-set or atomic get-and-add? Used
96 // to guide intrinsification decisions for Unsafe atomic ops
97 static bool supports_atomic_getset4() {return _supports_atomic_getset4;}
98 static bool supports_atomic_getset8() {return _supports_atomic_getset8;}
99 static bool supports_atomic_getadd4() {return _supports_atomic_getadd4;}
100 static bool supports_atomic_getadd8() {return _supports_atomic_getadd8;}
101
102 static unsigned int logical_processors_per_package() {
103 return _logical_processors_per_package;
104 }
105
106 // Need a space at the end of TLAB for prefetch instructions
107 // which may fault when accessing memory outside of heap.
108 static int reserve_for_allocation_prefetch() {
109 return _reserve_for_allocation_prefetch;
110 }
111
112 // ARCH specific policy for the BiasedLocking
113 static bool use_biased_locking() { return true; }
114
115 // Number of page sizes efficiently supported by the hardware. Most chips now
116 // support two sizes, thus this default implementation. Processor-specific
117 // subclasses should define new versions to hide this one as needed. Note
118 // that the O/S may support more sizes, but at most this many are used.
119 static uint page_size_count() { return 2; }
120
121 // Returns the number of parallel threads to be used for VM
122 // work. If that number has not been calculated, do so and
123 // save it. Returns ParallelGCThreads if it is set on the
124 // command line.
125 static unsigned int parallel_worker_threads();
126 // Calculates and returns the number of parallel threads. May
127 // be VM version specific.
128 static unsigned int calc_parallel_worker_threads();
129 };
130
131 #endif // SHARE_VM_RUNTIME_VM_VERSION_HPP