Thu, 25 Sep 2008 12:50:51 -0700
6744783: HotSpot segfaults if given -XX options with an empty string argument
Reviewed-by: kamg, kvn
Contributed-by: volker.simonis@gmail.com
1 /*
2 * Copyright 1997-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 // ReservedSpace is a data structure for reserving a contiguous address range.
27 class ReservedSpace VALUE_OBJ_CLASS_SPEC {
28 friend class VMStructs;
29 private:
30 char* _base;
31 size_t _size;
32 size_t _noaccess_prefix;
33 size_t _alignment;
34 bool _special;
36 // ReservedSpace
37 ReservedSpace(char* base, size_t size, size_t alignment, bool special);
38 void initialize(size_t size, size_t alignment, bool large,
39 char* requested_address,
40 const size_t noaccess_prefix);
42 // Release parts of an already-reserved memory region [addr, addr + len) to
43 // get a new region that has "compound alignment." Return the start of the
44 // resulting region, or NULL on failure.
45 //
46 // The region is logically divided into a prefix and a suffix. The prefix
47 // starts at the result address, which is aligned to prefix_align. The suffix
48 // starts at result address + prefix_size, which is aligned to suffix_align.
49 // The total size of the result region is size prefix_size + suffix_size.
50 char* align_reserved_region(char* addr, const size_t len,
51 const size_t prefix_size,
52 const size_t prefix_align,
53 const size_t suffix_size,
54 const size_t suffix_align);
56 // Reserve memory, call align_reserved_region() to alignment it and return the
57 // result.
58 char* reserve_and_align(const size_t reserve_size,
59 const size_t prefix_size,
60 const size_t prefix_align,
61 const size_t suffix_size,
62 const size_t suffix_align);
64 protected:
65 // Create protection page at the beginning of the space.
66 void protect_noaccess_prefix(const size_t size);
68 public:
69 // Constructor
70 ReservedSpace(size_t size);
71 ReservedSpace(size_t size, size_t alignment, bool large,
72 char* requested_address = NULL,
73 const size_t noaccess_prefix = 0);
74 ReservedSpace(const size_t prefix_size, const size_t prefix_align,
75 const size_t suffix_size, const size_t suffix_align,
76 const size_t noaccess_prefix);
78 // Accessors
79 char* base() const { return _base; }
80 size_t size() const { return _size; }
81 size_t alignment() const { return _alignment; }
82 bool special() const { return _special; }
84 size_t noaccess_prefix() const { return _noaccess_prefix; }
86 bool is_reserved() const { return _base != NULL; }
87 void release();
89 // Splitting
90 ReservedSpace first_part(size_t partition_size, size_t alignment,
91 bool split = false, bool realloc = true);
92 ReservedSpace last_part (size_t partition_size, size_t alignment);
94 // These simply call the above using the default alignment.
95 inline ReservedSpace first_part(size_t partition_size,
96 bool split = false, bool realloc = true);
97 inline ReservedSpace last_part (size_t partition_size);
99 // Alignment
100 static size_t page_align_size_up(size_t size);
101 static size_t page_align_size_down(size_t size);
102 static size_t allocation_align_size_up(size_t size);
103 static size_t allocation_align_size_down(size_t size);
104 };
106 ReservedSpace
107 ReservedSpace::first_part(size_t partition_size, bool split, bool realloc)
108 {
109 return first_part(partition_size, alignment(), split, realloc);
110 }
112 ReservedSpace ReservedSpace::last_part(size_t partition_size)
113 {
114 return last_part(partition_size, alignment());
115 }
117 // Class encapsulating behavior specific of memory space reserved for Java heap
118 class ReservedHeapSpace : public ReservedSpace {
119 public:
120 // Constructor
121 ReservedHeapSpace(size_t size, size_t forced_base_alignment,
122 bool large, char* requested_address);
123 ReservedHeapSpace(const size_t prefix_size, const size_t prefix_align,
124 const size_t suffix_size, const size_t suffix_align);
125 };
127 // VirtualSpace is data structure for committing a previously reserved address range in smaller chunks.
129 class VirtualSpace VALUE_OBJ_CLASS_SPEC {
130 friend class VMStructs;
131 private:
132 // Reserved area
133 char* _low_boundary;
134 char* _high_boundary;
136 // Committed area
137 char* _low;
138 char* _high;
140 // The entire space has been committed and pinned in memory, no
141 // os::commit_memory() or os::uncommit_memory().
142 bool _special;
144 // MPSS Support
145 // Each virtualspace region has a lower, middle, and upper region.
146 // Each region has an end boundary and a high pointer which is the
147 // high water mark for the last allocated byte.
148 // The lower and upper unaligned to LargePageSizeInBytes uses default page.
149 // size. The middle region uses large page size.
150 char* _lower_high;
151 char* _middle_high;
152 char* _upper_high;
154 char* _lower_high_boundary;
155 char* _middle_high_boundary;
156 char* _upper_high_boundary;
158 size_t _lower_alignment;
159 size_t _middle_alignment;
160 size_t _upper_alignment;
162 // MPSS Accessors
163 char* lower_high() const { return _lower_high; }
164 char* middle_high() const { return _middle_high; }
165 char* upper_high() const { return _upper_high; }
167 char* lower_high_boundary() const { return _lower_high_boundary; }
168 char* middle_high_boundary() const { return _middle_high_boundary; }
169 char* upper_high_boundary() const { return _upper_high_boundary; }
171 size_t lower_alignment() const { return _lower_alignment; }
172 size_t middle_alignment() const { return _middle_alignment; }
173 size_t upper_alignment() const { return _upper_alignment; }
175 public:
176 // Committed area
177 char* low() const { return _low; }
178 char* high() const { return _high; }
180 // Reserved area
181 char* low_boundary() const { return _low_boundary; }
182 char* high_boundary() const { return _high_boundary; }
184 bool special() const { return _special; }
186 public:
187 // Initialization
188 VirtualSpace();
189 bool initialize(ReservedSpace rs, size_t committed_byte_size);
191 // Destruction
192 ~VirtualSpace();
194 // Testers (all sizes are byte sizes)
195 size_t committed_size() const;
196 size_t reserved_size() const;
197 size_t uncommitted_size() const;
198 bool contains(const void* p) const;
200 // Operations
201 // returns true on success, false otherwise
202 bool expand_by(size_t bytes, bool pre_touch = false);
203 void shrink_by(size_t bytes);
204 void release();
206 void check_for_contiguity() PRODUCT_RETURN;
208 // Debugging
209 void print() PRODUCT_RETURN;
210 };