1 /*
2 * Copyright (c) 1997, 2011, 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 // Name
60 static const char* vm_name();
61 // Vendor
62 static const char* vm_vendor();
63 // VM version information string printed by launcher (java -version)
64 static const char* vm_info_string();
65 static const char* vm_release();
66 static const char* vm_platform_string();
67 static const char* vm_build_user();
68
69 static int vm_major_version() { assert(_initialized, "not initialized"); return _vm_major_version; }
70 static int vm_minor_version() { assert(_initialized, "not initialized"); return _vm_minor_version; }
71 static int vm_build_number() { assert(_initialized, "not initialized"); return _vm_build_number; }
72
73 // Gets the jvm_version_info.jvm_version defined in jvm.h
74 static unsigned int jvm_version();
75
76 // Internal version providing additional build information
77 static const char* internal_vm_info_string();
78 static const char* jre_release_version();
79
80 // does HW support an 8-byte compare-exchange operation?
81 static bool supports_cx8() {return _supports_cx8;}
82 // does HW support atomic get-and-set or atomic get-and-add? Used
83 // to guide intrinsification decisions for Unsafe atomic ops
84 static bool supports_atomic_getset4() {return _supports_atomic_getset4;}
85 static bool supports_atomic_getset8() {return _supports_atomic_getset8;}
86 static bool supports_atomic_getadd4() {return _supports_atomic_getadd4;}
87 static bool supports_atomic_getadd8() {return _supports_atomic_getadd8;}
88
89 static unsigned int logical_processors_per_package() {
90 return _logical_processors_per_package;
91 }
92
93 // Need a space at the end of TLAB for prefetch instructions
94 // which may fault when accessing memory outside of heap.
95 static int reserve_for_allocation_prefetch() {
96 return _reserve_for_allocation_prefetch;
97 }
98
99 // ARCH specific policy for the BiasedLocking
100 static bool use_biased_locking() { return true; }
101
102 // Number of page sizes efficiently supported by the hardware. Most chips now
103 // support two sizes, thus this default implementation. Processor-specific
104 // subclasses should define new versions to hide this one as needed. Note
105 // that the O/S may support more sizes, but at most this many are used.
106 static uint page_size_count() { return 2; }
107
108 // Returns the number of parallel threads to be used for VM
109 // work. If that number has not been calculated, do so and
110 // save it. Returns ParallelGCThreads if it is set on the
111 // command line.
112 static unsigned int parallel_worker_threads();
113 // Calculates and returns the number of parallel threads. May
114 // be VM version specific.
115 static unsigned int calc_parallel_worker_threads();
116 };
117
118 #endif // SHARE_VM_RUNTIME_VM_VERSION_HPP