1 /*
2 * Copyright (c) 1997, 2018, 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
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23 */
24
25 #ifndef SHARE_VM_RUNTIME_VIRTUALSPACE_HPP
26 #define SHARE_VM_RUNTIME_VIRTUALSPACE_HPP
27
28 #include "utilities/globalDefinitions.hpp"
29
30 // ReservedSpace is a data structure for reserving a contiguous address range.
31
32 class ReservedSpace {
33 friend class VMStructs;
34 protected:
35 char* _base;
36 size_t _size;
37 size_t _noaccess_prefix;
38 size_t _alignment;
39 bool _special;
40 int _fd_for_heap;
41 private:
42 bool _executable;
43
44 // ReservedSpace
45 ReservedSpace(char* base, size_t size, size_t alignment, bool special,
46 bool executable);
47 protected:
48 void initialize(size_t size, size_t alignment, bool large,
49 char* requested_address,
50 bool executable);
51
52 public:
53 // Constructor
54 ReservedSpace();
55 // Initialize the reserved space with the given size. If preferred_page_size
56 // is set, use this as minimum page size/alignment. This may waste some space
57 // if the given size is not aligned to that value, as the reservation will be
58 // aligned up to the final alignment in this case.
59 ReservedSpace(size_t size, size_t preferred_page_size = 0);
60 ReservedSpace(size_t size, size_t alignment, bool large,
61 char* requested_address = NULL);
62 ReservedSpace(size_t size, size_t alignment, bool large, bool executable);
63
64 // Accessors
65 char* base() const { return _base; }
66 int nvdimm_fd() const { return _fd_for_heap; }
67 void setup_fd(int fd) {_fd_for_heap = fd; }
68 size_t size() const { return _size; }
69 char* end() const { return _base + _size; }
70 size_t alignment() const { return _alignment; }
71 bool special() const { return _special; }
72 bool executable() const { return _executable; }
73 size_t noaccess_prefix() const { return _noaccess_prefix; }
74 bool is_reserved() const { return _base != NULL; }
75 void release();
76
77 // Splitting
78 ReservedSpace first_part(size_t partition_size, size_t alignment,
79 bool split = false, bool realloc = true);
80 ReservedSpace last_part (size_t partition_size, size_t alignment);
81
82 // These simply call the above using the default alignment.
83 inline ReservedSpace first_part(size_t partition_size,
84 bool split = false, bool realloc = true);
85 inline ReservedSpace last_part (size_t partition_size);
86
87 // Alignment
88 static size_t page_align_size_up(size_t size);
89 static size_t page_align_size_down(size_t size);
90 static size_t allocation_align_size_up(size_t size);
91 static size_t allocation_align_size_down(size_t size);
92 bool contains(const void* p) const {
93 return (base() <= ((char*)p)) && (((char*)p) < (base() + size()));
94 }
95 };
96
97 ReservedSpace
98 ReservedSpace::first_part(size_t partition_size, bool split, bool realloc)
99 {
100 return first_part(partition_size, alignment(), split, realloc);
101 }
102
103 ReservedSpace ReservedSpace::last_part(size_t partition_size)
104 {
105 return last_part(partition_size, alignment());
106 }
107
108 // Class encapsulating behavior specific of memory space reserved for Java heap.
109 class ReservedHeapSpace : public ReservedSpace {
110 private:
111 void try_reserve_heap(size_t size, size_t alignment, bool large,
112 char *requested_address);
113 void try_reserve_range(char *highest_start, char *lowest_start,
114 size_t attach_point_alignment, char *aligned_HBMA,
115 char *upper_bound, size_t size, size_t alignment, bool large);
116 void initialize_compressed_heap(const size_t size, size_t alignment, bool large);
117 // Create protection page at the beginning of the space.
118 void establish_noaccess_prefix();
119 public:
120 // Constructor. Tries to find a heap that is good for compressed oops.
121 // heap_allocation_directory is the path to the backing memory for Java heap. When set, Java heap will be allocated
122 // on the device which is managed by the file system where the directory resides.
123 ReservedHeapSpace(size_t size, size_t forced_base_alignment, bool large, const char* heap_allocation_directory = NULL);
124 // Returns the base to be used for compression, i.e. so that null can be
125 // encoded safely and implicit null checks can work.
126 char *compressed_oop_base() { return _base - _noaccess_prefix; }
127 };
128
129 // Class encapsulating behavior specific memory space for Code
130 class ReservedCodeSpace : public ReservedSpace {
131 public:
132 // Constructor
133 ReservedCodeSpace(size_t r_size, size_t rs_align, bool large);
134 };
135
136 // VirtualSpace is data structure for committing a previously reserved address range in smaller chunks.
137
138 class VirtualSpace {
139 friend class VMStructs;
140 private:
141 // Reserved area
142 char* _low_boundary;
143 char* _high_boundary;
144
145 // Committed area
146 char* _low;
147 char* _high;
148
149 // The entire space has been committed and pinned in memory, no
150 // os::commit_memory() or os::uncommit_memory().
151 bool _special;
152
153 // Need to know if commit should be executable.
154 bool _executable;
155
156 // MPSS Support
157 // Each virtualspace region has a lower, middle, and upper region.
158 // Each region has an end boundary and a high pointer which is the
159 // high water mark for the last allocated byte.
160 // The lower and upper unaligned to LargePageSizeInBytes uses default page.
161 // size. The middle region uses large page size.
162 char* _lower_high;
163 char* _middle_high;
164 char* _upper_high;
165
166 char* _lower_high_boundary;
167 char* _middle_high_boundary;
168 char* _upper_high_boundary;
169
170 size_t _lower_alignment;
171 size_t _middle_alignment;
172 size_t _upper_alignment;
173
174 // MPSS Accessors
175 char* lower_high() const { return _lower_high; }
176 char* middle_high() const { return _middle_high; }
177 char* upper_high() const { return _upper_high; }
178
179 char* lower_high_boundary() const { return _lower_high_boundary; }
180 char* middle_high_boundary() const { return _middle_high_boundary; }
181 char* upper_high_boundary() const { return _upper_high_boundary; }
182
183 size_t lower_alignment() const { return _lower_alignment; }
184 size_t middle_alignment() const { return _middle_alignment; }
185 size_t upper_alignment() const { return _upper_alignment; }
186
187 public:
188 // Committed area
189 char* low() const { return _low; }
190 char* high() const { return _high; }
191
192 // Reserved area
193 char* low_boundary() const { return _low_boundary; }
194 char* high_boundary() const { return _high_boundary; }
195
196 #if INCLUDE_AOT
197 // Set boundaries for code section in AOT library.
198 void set_low_boundary(char *p) { _low_boundary = p; }
199 void set_high_boundary(char *p) { _high_boundary = p; }
200 void set_low(char *p) { _low = p; }
201 void set_high(char *p) { _high = p; }
202 #endif
203
204 bool special() const { return _special; }
205
206 public:
207 // Initialization
208 VirtualSpace();
209 bool initialize_with_granularity(ReservedSpace rs, size_t committed_byte_size, size_t max_commit_ganularity);
210 bool initialize(ReservedSpace rs, size_t committed_byte_size);
211
212 // Destruction
213 ~VirtualSpace();
214
215 // Reserved memory
216 size_t reserved_size() const;
217 // Actually committed OS memory
218 size_t actual_committed_size() const;
219 // Memory used/expanded in this virtual space
220 size_t committed_size() const;
221 // Memory left to use/expand in this virtual space
222 size_t uncommitted_size() const;
223
224 bool contains(const void* p) const;
225
226 // Operations
227 // returns true on success, false otherwise
228 bool expand_by(size_t bytes, bool pre_touch = false);
229 void shrink_by(size_t bytes);
230 void release();
231
232 void check_for_contiguity() PRODUCT_RETURN;
233
234 // Debugging
235 void print_on(outputStream* out) PRODUCT_RETURN;
236 void print();
237 };
238
239 #endif // SHARE_VM_RUNTIME_VIRTUALSPACE_HPP