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0
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1 /*
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2 * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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4 *
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5 * This code is free software; you can redistribute it and/or modify it
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6 * under the terms of the GNU General Public License version 2 only, as
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7 * published by the Free Software Foundation.
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8 *
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9 * This code is distributed in the hope that it will be useful, but WITHOUT
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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12 * version 2 for more details (a copy is included in the LICENSE file that
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13 * accompanied this code).
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14 *
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15 * You should have received a copy of the GNU General Public License version
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16 * 2 along with this work; if not, write to the Free Software Foundation,
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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18 *
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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20 * CA 95054 USA or visit www.sun.com if you need additional information or
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21 * have any questions.
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22 *
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23 */
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24
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25 #include "incls/_precompiled.incl"
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26 #include "incls/_virtualspace.cpp.incl"
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27
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28
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29 // ReservedSpace
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30 ReservedSpace::ReservedSpace(size_t size) {
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31 initialize(size, 0, false, NULL);
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32 }
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33
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34 ReservedSpace::ReservedSpace(size_t size, size_t alignment,
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35 bool large, char* requested_address) {
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36 initialize(size, alignment, large, requested_address);
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37 }
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38
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39 char *
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40 ReservedSpace::align_reserved_region(char* addr, const size_t len,
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41 const size_t prefix_size,
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42 const size_t prefix_align,
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43 const size_t suffix_size,
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44 const size_t suffix_align)
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45 {
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46 assert(addr != NULL, "sanity");
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47 const size_t required_size = prefix_size + suffix_size;
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48 assert(len >= required_size, "len too small");
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49
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50 const size_t s = size_t(addr);
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51 const size_t beg_ofs = s + prefix_size & suffix_align - 1;
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52 const size_t beg_delta = beg_ofs == 0 ? 0 : suffix_align - beg_ofs;
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53
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54 if (len < beg_delta + required_size) {
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55 return NULL; // Cannot do proper alignment.
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56 }
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57 const size_t end_delta = len - (beg_delta + required_size);
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58
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59 if (beg_delta != 0) {
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60 os::release_memory(addr, beg_delta);
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61 }
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62
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63 if (end_delta != 0) {
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64 char* release_addr = (char*) (s + beg_delta + required_size);
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65 os::release_memory(release_addr, end_delta);
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66 }
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67
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68 return (char*) (s + beg_delta);
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69 }
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70
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71 char* ReservedSpace::reserve_and_align(const size_t reserve_size,
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72 const size_t prefix_size,
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73 const size_t prefix_align,
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74 const size_t suffix_size,
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75 const size_t suffix_align)
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76 {
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77 assert(reserve_size > prefix_size + suffix_size, "should not be here");
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78
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79 char* raw_addr = os::reserve_memory(reserve_size, NULL, prefix_align);
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80 if (raw_addr == NULL) return NULL;
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81
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82 char* result = align_reserved_region(raw_addr, reserve_size, prefix_size,
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83 prefix_align, suffix_size,
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84 suffix_align);
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85 if (result == NULL && !os::release_memory(raw_addr, reserve_size)) {
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86 fatal("os::release_memory failed");
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87 }
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88
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89 #ifdef ASSERT
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90 if (result != NULL) {
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91 const size_t raw = size_t(raw_addr);
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92 const size_t res = size_t(result);
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93 assert(res >= raw, "alignment decreased start addr");
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94 assert(res + prefix_size + suffix_size <= raw + reserve_size,
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95 "alignment increased end addr");
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96 assert((res & prefix_align - 1) == 0, "bad alignment of prefix");
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97 assert((res + prefix_size & suffix_align - 1) == 0,
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98 "bad alignment of suffix");
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99 }
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100 #endif
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101
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102 return result;
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103 }
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104
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105 ReservedSpace::ReservedSpace(const size_t prefix_size,
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106 const size_t prefix_align,
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107 const size_t suffix_size,
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108 const size_t suffix_align)
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109 {
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110 assert(prefix_size != 0, "sanity");
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111 assert(prefix_align != 0, "sanity");
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112 assert(suffix_size != 0, "sanity");
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113 assert(suffix_align != 0, "sanity");
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114 assert((prefix_size & prefix_align - 1) == 0,
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115 "prefix_size not divisible by prefix_align");
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116 assert((suffix_size & suffix_align - 1) == 0,
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117 "suffix_size not divisible by suffix_align");
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118 assert((suffix_align & prefix_align - 1) == 0,
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119 "suffix_align not divisible by prefix_align");
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120
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121 // On systems where the entire region has to be reserved and committed up
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122 // front, the compound alignment normally done by this method is unnecessary.
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123 const bool try_reserve_special = UseLargePages &&
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124 prefix_align == os::large_page_size();
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125 if (!os::can_commit_large_page_memory() && try_reserve_special) {
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126 initialize(prefix_size + suffix_size, prefix_align, true);
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127 return;
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128 }
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129
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130 _base = NULL;
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131 _size = 0;
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132 _alignment = 0;
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133 _special = false;
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134
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135 // Optimistically try to reserve the exact size needed.
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136 const size_t size = prefix_size + suffix_size;
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137 char* addr = os::reserve_memory(size, NULL, prefix_align);
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138 if (addr == NULL) return;
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139
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140 // Check whether the result has the needed alignment (unlikely unless
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141 // prefix_align == suffix_align).
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142 const size_t ofs = size_t(addr) + prefix_size & suffix_align - 1;
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143 if (ofs != 0) {
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144 // Wrong alignment. Release, allocate more space and do manual alignment.
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145 //
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146 // On most operating systems, another allocation with a somewhat larger size
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147 // will return an address "close to" that of the previous allocation. The
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148 // result is often the same address (if the kernel hands out virtual
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149 // addresses from low to high), or an address that is offset by the increase
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150 // in size. Exploit that to minimize the amount of extra space requested.
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151 if (!os::release_memory(addr, size)) {
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152 fatal("os::release_memory failed");
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153 }
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154
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155 const size_t extra = MAX2(ofs, suffix_align - ofs);
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156 addr = reserve_and_align(size + extra, prefix_size, prefix_align,
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157 suffix_size, suffix_align);
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158 if (addr == NULL) {
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159 // Try an even larger region. If this fails, address space is exhausted.
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160 addr = reserve_and_align(size + suffix_align, prefix_size,
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161 prefix_align, suffix_size, suffix_align);
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162 }
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163 }
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164
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165 _base = addr;
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166 _size = size;
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167 _alignment = prefix_align;
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168 }
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169
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170 void ReservedSpace::initialize(size_t size, size_t alignment, bool large,
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171 char* requested_address) {
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172 const size_t granularity = os::vm_allocation_granularity();
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173 assert((size & granularity - 1) == 0,
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174 "size not aligned to os::vm_allocation_granularity()");
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175 assert((alignment & granularity - 1) == 0,
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176 "alignment not aligned to os::vm_allocation_granularity()");
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177 assert(alignment == 0 || is_power_of_2((intptr_t)alignment),
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178 "not a power of 2");
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179
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180 _base = NULL;
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181 _size = 0;
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182 _special = false;
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183 _alignment = 0;
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184 if (size == 0) {
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185 return;
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186 }
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187
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188 // If OS doesn't support demand paging for large page memory, we need
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189 // to use reserve_memory_special() to reserve and pin the entire region.
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190 bool special = large && !os::can_commit_large_page_memory();
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191 char* base = NULL;
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192
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193 if (special) {
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194 // It's not hard to implement reserve_memory_special() such that it can
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195 // allocate at fixed address, but there seems no use of this feature
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196 // for now, so it's not implemented.
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197 assert(requested_address == NULL, "not implemented");
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198
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199 base = os::reserve_memory_special(size);
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200
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201 if (base != NULL) {
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202 // Check alignment constraints
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203 if (alignment > 0) {
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204 assert((uintptr_t) base % alignment == 0,
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205 "Large pages returned a non-aligned address");
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206 }
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207 _special = true;
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208 } else {
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209 // failed; try to reserve regular memory below
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210 }
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211 }
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212
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213 if (base == NULL) {
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214 // Optimistically assume that the OSes returns an aligned base pointer.
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215 // When reserving a large address range, most OSes seem to align to at
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216 // least 64K.
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217
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218 // If the memory was requested at a particular address, use
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219 // os::attempt_reserve_memory_at() to avoid over mapping something
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220 // important. If available space is not detected, return NULL.
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221
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222 if (requested_address != 0) {
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223 base = os::attempt_reserve_memory_at(size, requested_address);
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224 } else {
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225 base = os::reserve_memory(size, NULL, alignment);
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226 }
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227
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228 if (base == NULL) return;
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229
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230 // Check alignment constraints
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231 if (alignment > 0 && ((size_t)base & alignment - 1) != 0) {
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232 // Base not aligned, retry
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233 if (!os::release_memory(base, size)) fatal("os::release_memory failed");
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234 // Reserve size large enough to do manual alignment and
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235 // increase size to a multiple of the desired alignment
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236 size = align_size_up(size, alignment);
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237 size_t extra_size = size + alignment;
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238 char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
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239 if (extra_base == NULL) return;
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240 // Do manual alignement
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241 base = (char*) align_size_up((uintptr_t) extra_base, alignment);
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242 assert(base >= extra_base, "just checking");
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243 // Release unused areas
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244 size_t unused_bottom_size = base - extra_base;
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245 size_t unused_top_size = extra_size - size - unused_bottom_size;
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246 assert(unused_bottom_size % os::vm_allocation_granularity() == 0,
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247 "size not allocation aligned");
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248 assert(unused_top_size % os::vm_allocation_granularity() == 0,
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249 "size not allocation aligned");
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250 if (unused_bottom_size > 0) {
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251 os::release_memory(extra_base, unused_bottom_size);
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252 }
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253 if (unused_top_size > 0) {
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254 os::release_memory(base + size, unused_top_size);
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255 }
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256 }
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257 }
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258 // Done
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259 _base = base;
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260 _size = size;
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261 _alignment = MAX2(alignment, (size_t) os::vm_page_size());
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262
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263 assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base,
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264 "area must be distinguisable from marks for mark-sweep");
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265 assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size],
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266 "area must be distinguisable from marks for mark-sweep");
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267 }
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268
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269
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270 ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment,
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271 bool special) {
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272 assert((size % os::vm_allocation_granularity()) == 0,
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273 "size not allocation aligned");
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274 _base = base;
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275 _size = size;
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276 _alignment = alignment;
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277 _special = special;
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278 }
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279
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280
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281 ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment,
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282 bool split, bool realloc) {
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283 assert(partition_size <= size(), "partition failed");
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284 if (split) {
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285 os::split_reserved_memory(_base, _size, partition_size, realloc);
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286 }
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287 ReservedSpace result(base(), partition_size, alignment, special());
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288 return result;
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289 }
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290
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291
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292 ReservedSpace
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293 ReservedSpace::last_part(size_t partition_size, size_t alignment) {
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294 assert(partition_size <= size(), "partition failed");
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295 ReservedSpace result(base() + partition_size, size() - partition_size,
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296 alignment, special());
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297 return result;
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298 }
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299
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300
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301 size_t ReservedSpace::page_align_size_up(size_t size) {
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302 return align_size_up(size, os::vm_page_size());
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303 }
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304
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305
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306 size_t ReservedSpace::page_align_size_down(size_t size) {
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307 return align_size_down(size, os::vm_page_size());
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308 }
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309
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310
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311 size_t ReservedSpace::allocation_align_size_up(size_t size) {
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312 return align_size_up(size, os::vm_allocation_granularity());
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313 }
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314
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315
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316 size_t ReservedSpace::allocation_align_size_down(size_t size) {
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317 return align_size_down(size, os::vm_allocation_granularity());
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318 }
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319
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320
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321 void ReservedSpace::release() {
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322 if (is_reserved()) {
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323 if (special()) {
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324 os::release_memory_special(_base, _size);
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325 } else{
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326 os::release_memory(_base, _size);
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327 }
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328 _base = NULL;
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329 _size = 0;
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330 _special = false;
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331 }
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332 }
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333
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334
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335 // VirtualSpace
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336
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337 VirtualSpace::VirtualSpace() {
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338 _low_boundary = NULL;
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339 _high_boundary = NULL;
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340 _low = NULL;
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341 _high = NULL;
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342 _lower_high = NULL;
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343 _middle_high = NULL;
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344 _upper_high = NULL;
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345 _lower_high_boundary = NULL;
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346 _middle_high_boundary = NULL;
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347 _upper_high_boundary = NULL;
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348 _lower_alignment = 0;
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349 _middle_alignment = 0;
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350 _upper_alignment = 0;
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351 }
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352
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353
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354 bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) {
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355 if(!rs.is_reserved()) return false; // allocation failed.
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356 assert(_low_boundary == NULL, "VirtualSpace already initialized");
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357 _low_boundary = rs.base();
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358 _high_boundary = low_boundary() + rs.size();
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359
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360 _low = low_boundary();
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361 _high = low();
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362
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363 _special = rs.special();
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364
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365 // When a VirtualSpace begins life at a large size, make all future expansion
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366 // and shrinking occur aligned to a granularity of large pages. This avoids
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367 // fragmentation of physical addresses that inhibits the use of large pages
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368 // by the OS virtual memory system. Empirically, we see that with a 4MB
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369 // page size, the only spaces that get handled this way are codecache and
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370 // the heap itself, both of which provide a substantial performance
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371 // boost in many benchmarks when covered by large pages.
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372 //
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373 // No attempt is made to force large page alignment at the very top and
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374 // bottom of the space if they are not aligned so already.
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375 _lower_alignment = os::vm_page_size();
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376 _middle_alignment = os::page_size_for_region(rs.size(), rs.size(), 1);
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377 _upper_alignment = os::vm_page_size();
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378
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379 // End of each region
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380 _lower_high_boundary = (char*) round_to((intptr_t) low_boundary(), middle_alignment());
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381 _middle_high_boundary = (char*) round_down((intptr_t) high_boundary(), middle_alignment());
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382 _upper_high_boundary = high_boundary();
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383
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384 // High address of each region
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385 _lower_high = low_boundary();
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386 _middle_high = lower_high_boundary();
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387 _upper_high = middle_high_boundary();
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388
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389 // commit to initial size
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390 if (committed_size > 0) {
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391 if (!expand_by(committed_size)) {
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392 return false;
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393 }
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394 }
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395 return true;
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396 }
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397
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398
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399 VirtualSpace::~VirtualSpace() {
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400 release();
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401 }
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402
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403
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404 void VirtualSpace::release() {
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405 (void)os::release_memory(low_boundary(), reserved_size());
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406 _low_boundary = NULL;
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407 _high_boundary = NULL;
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408 _low = NULL;
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409 _high = NULL;
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410 _lower_high = NULL;
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411 _middle_high = NULL;
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412 _upper_high = NULL;
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413 _lower_high_boundary = NULL;
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414 _middle_high_boundary = NULL;
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415 _upper_high_boundary = NULL;
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416 _lower_alignment = 0;
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417 _middle_alignment = 0;
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418 _upper_alignment = 0;
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419 _special = false;
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420 }
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421
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422
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423 size_t VirtualSpace::committed_size() const {
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424 return pointer_delta(high(), low(), sizeof(char));
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425 }
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426
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427
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428 size_t VirtualSpace::reserved_size() const {
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429 return pointer_delta(high_boundary(), low_boundary(), sizeof(char));
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430 }
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431
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432
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433 size_t VirtualSpace::uncommitted_size() const {
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434 return reserved_size() - committed_size();
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435 }
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436
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437
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438 bool VirtualSpace::contains(const void* p) const {
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439 return low() <= (const char*) p && (const char*) p < high();
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440 }
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441
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442 /*
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443 First we need to determine if a particular virtual space is using large
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444 pages. This is done at the initialize function and only virtual spaces
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445 that are larger than LargePageSizeInBytes use large pages. Once we
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446 have determined this, all expand_by and shrink_by calls must grow and
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447 shrink by large page size chunks. If a particular request
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448 is within the current large page, the call to commit and uncommit memory
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|
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449 can be ignored. In the case that the low and high boundaries of this
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450 space is not large page aligned, the pages leading to the first large
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|
|
451 page address and the pages after the last large page address must be
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|
|
452 allocated with default pages.
|
|
|
453 */
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|
|
454 bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) {
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|
455 if (uncommitted_size() < bytes) return false;
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|
|
456
|
|
|
457 if (special()) {
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|
|
458 // don't commit memory if the entire space is pinned in memory
|
|
|
459 _high += bytes;
|
|
|
460 return true;
|
|
|
461 }
|
|
|
462
|
|
|
463 char* previous_high = high();
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|
|
464 char* unaligned_new_high = high() + bytes;
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|
|
465 assert(unaligned_new_high <= high_boundary(),
|
|
|
466 "cannot expand by more than upper boundary");
|
|
|
467
|
|
|
468 // Calculate where the new high for each of the regions should be. If
|
|
|
469 // the low_boundary() and high_boundary() are LargePageSizeInBytes aligned
|
|
|
470 // then the unaligned lower and upper new highs would be the
|
|
|
471 // lower_high() and upper_high() respectively.
|
|
|
472 char* unaligned_lower_new_high =
|
|
|
473 MIN2(unaligned_new_high, lower_high_boundary());
|
|
|
474 char* unaligned_middle_new_high =
|
|
|
475 MIN2(unaligned_new_high, middle_high_boundary());
|
|
|
476 char* unaligned_upper_new_high =
|
|
|
477 MIN2(unaligned_new_high, upper_high_boundary());
|
|
|
478
|
|
|
479 // Align the new highs based on the regions alignment. lower and upper
|
|
|
480 // alignment will always be default page size. middle alignment will be
|
|
|
481 // LargePageSizeInBytes if the actual size of the virtual space is in
|
|
|
482 // fact larger than LargePageSizeInBytes.
|
|
|
483 char* aligned_lower_new_high =
|
|
|
484 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
|
|
|
485 char* aligned_middle_new_high =
|
|
|
486 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
|
|
|
487 char* aligned_upper_new_high =
|
|
|
488 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
|
|
|
489
|
|
|
490 // Determine which regions need to grow in this expand_by call.
|
|
|
491 // If you are growing in the lower region, high() must be in that
|
|
|
492 // region so calcuate the size based on high(). For the middle and
|
|
|
493 // upper regions, determine the starting point of growth based on the
|
|
|
494 // location of high(). By getting the MAX of the region's low address
|
|
|
495 // (or the prevoius region's high address) and high(), we can tell if it
|
|
|
496 // is an intra or inter region growth.
|
|
|
497 size_t lower_needs = 0;
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|
|
498 if (aligned_lower_new_high > lower_high()) {
|
|
|
499 lower_needs =
|
|
|
500 pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char));
|
|
|
501 }
|
|
|
502 size_t middle_needs = 0;
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|
|
503 if (aligned_middle_new_high > middle_high()) {
|
|
|
504 middle_needs =
|
|
|
505 pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char));
|
|
|
506 }
|
|
|
507 size_t upper_needs = 0;
|
|
|
508 if (aligned_upper_new_high > upper_high()) {
|
|
|
509 upper_needs =
|
|
|
510 pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char));
|
|
|
511 }
|
|
|
512
|
|
|
513 // Check contiguity.
|
|
|
514 assert(low_boundary() <= lower_high() &&
|
|
|
515 lower_high() <= lower_high_boundary(),
|
|
|
516 "high address must be contained within the region");
|
|
|
517 assert(lower_high_boundary() <= middle_high() &&
|
|
|
518 middle_high() <= middle_high_boundary(),
|
|
|
519 "high address must be contained within the region");
|
|
|
520 assert(middle_high_boundary() <= upper_high() &&
|
|
|
521 upper_high() <= upper_high_boundary(),
|
|
|
522 "high address must be contained within the region");
|
|
|
523
|
|
|
524 // Commit regions
|
|
|
525 if (lower_needs > 0) {
|
|
|
526 assert(low_boundary() <= lower_high() &&
|
|
|
527 lower_high() + lower_needs <= lower_high_boundary(),
|
|
|
528 "must not expand beyond region");
|
|
|
529 if (!os::commit_memory(lower_high(), lower_needs)) {
|
|
|
530 debug_only(warning("os::commit_memory failed"));
|
|
|
531 return false;
|
|
|
532 } else {
|
|
|
533 _lower_high += lower_needs;
|
|
|
534 }
|
|
|
535 }
|
|
|
536 if (middle_needs > 0) {
|
|
|
537 assert(lower_high_boundary() <= middle_high() &&
|
|
|
538 middle_high() + middle_needs <= middle_high_boundary(),
|
|
|
539 "must not expand beyond region");
|
|
|
540 if (!os::commit_memory(middle_high(), middle_needs, middle_alignment())) {
|
|
|
541 debug_only(warning("os::commit_memory failed"));
|
|
|
542 return false;
|
|
|
543 }
|
|
|
544 _middle_high += middle_needs;
|
|
|
545 }
|
|
|
546 if (upper_needs > 0) {
|
|
|
547 assert(middle_high_boundary() <= upper_high() &&
|
|
|
548 upper_high() + upper_needs <= upper_high_boundary(),
|
|
|
549 "must not expand beyond region");
|
|
|
550 if (!os::commit_memory(upper_high(), upper_needs)) {
|
|
|
551 debug_only(warning("os::commit_memory failed"));
|
|
|
552 return false;
|
|
|
553 } else {
|
|
|
554 _upper_high += upper_needs;
|
|
|
555 }
|
|
|
556 }
|
|
|
557
|
|
|
558 if (pre_touch || AlwaysPreTouch) {
|
|
|
559 int vm_ps = os::vm_page_size();
|
|
|
560 for (char* curr = previous_high;
|
|
|
561 curr < unaligned_new_high;
|
|
|
562 curr += vm_ps) {
|
|
|
563 // Note the use of a write here; originally we tried just a read, but
|
|
|
564 // since the value read was unused, the optimizer removed the read.
|
|
|
565 // If we ever have a concurrent touchahead thread, we'll want to use
|
|
|
566 // a read, to avoid the potential of overwriting data (if a mutator
|
|
|
567 // thread beats the touchahead thread to a page). There are various
|
|
|
568 // ways of making sure this read is not optimized away: for example,
|
|
|
569 // generating the code for a read procedure at runtime.
|
|
|
570 *curr = 0;
|
|
|
571 }
|
|
|
572 }
|
|
|
573
|
|
|
574 _high += bytes;
|
|
|
575 return true;
|
|
|
576 }
|
|
|
577
|
|
|
578 // A page is uncommitted if the contents of the entire page is deemed unusable.
|
|
|
579 // Continue to decrement the high() pointer until it reaches a page boundary
|
|
|
580 // in which case that particular page can now be uncommitted.
|
|
|
581 void VirtualSpace::shrink_by(size_t size) {
|
|
|
582 if (committed_size() < size)
|
|
|
583 fatal("Cannot shrink virtual space to negative size");
|
|
|
584
|
|
|
585 if (special()) {
|
|
|
586 // don't uncommit if the entire space is pinned in memory
|
|
|
587 _high -= size;
|
|
|
588 return;
|
|
|
589 }
|
|
|
590
|
|
|
591 char* unaligned_new_high = high() - size;
|
|
|
592 assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary");
|
|
|
593
|
|
|
594 // Calculate new unaligned address
|
|
|
595 char* unaligned_upper_new_high =
|
|
|
596 MAX2(unaligned_new_high, middle_high_boundary());
|
|
|
597 char* unaligned_middle_new_high =
|
|
|
598 MAX2(unaligned_new_high, lower_high_boundary());
|
|
|
599 char* unaligned_lower_new_high =
|
|
|
600 MAX2(unaligned_new_high, low_boundary());
|
|
|
601
|
|
|
602 // Align address to region's alignment
|
|
|
603 char* aligned_upper_new_high =
|
|
|
604 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment());
|
|
|
605 char* aligned_middle_new_high =
|
|
|
606 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment());
|
|
|
607 char* aligned_lower_new_high =
|
|
|
608 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment());
|
|
|
609
|
|
|
610 // Determine which regions need to shrink
|
|
|
611 size_t upper_needs = 0;
|
|
|
612 if (aligned_upper_new_high < upper_high()) {
|
|
|
613 upper_needs =
|
|
|
614 pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char));
|
|
|
615 }
|
|
|
616 size_t middle_needs = 0;
|
|
|
617 if (aligned_middle_new_high < middle_high()) {
|
|
|
618 middle_needs =
|
|
|
619 pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char));
|
|
|
620 }
|
|
|
621 size_t lower_needs = 0;
|
|
|
622 if (aligned_lower_new_high < lower_high()) {
|
|
|
623 lower_needs =
|
|
|
624 pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char));
|
|
|
625 }
|
|
|
626
|
|
|
627 // Check contiguity.
|
|
|
628 assert(middle_high_boundary() <= upper_high() &&
|
|
|
629 upper_high() <= upper_high_boundary(),
|
|
|
630 "high address must be contained within the region");
|
|
|
631 assert(lower_high_boundary() <= middle_high() &&
|
|
|
632 middle_high() <= middle_high_boundary(),
|
|
|
633 "high address must be contained within the region");
|
|
|
634 assert(low_boundary() <= lower_high() &&
|
|
|
635 lower_high() <= lower_high_boundary(),
|
|
|
636 "high address must be contained within the region");
|
|
|
637
|
|
|
638 // Uncommit
|
|
|
639 if (upper_needs > 0) {
|
|
|
640 assert(middle_high_boundary() <= aligned_upper_new_high &&
|
|
|
641 aligned_upper_new_high + upper_needs <= upper_high_boundary(),
|
|
|
642 "must not shrink beyond region");
|
|
|
643 if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) {
|
|
|
644 debug_only(warning("os::uncommit_memory failed"));
|
|
|
645 return;
|
|
|
646 } else {
|
|
|
647 _upper_high -= upper_needs;
|
|
|
648 }
|
|
|
649 }
|
|
|
650 if (middle_needs > 0) {
|
|
|
651 assert(lower_high_boundary() <= aligned_middle_new_high &&
|
|
|
652 aligned_middle_new_high + middle_needs <= middle_high_boundary(),
|
|
|
653 "must not shrink beyond region");
|
|
|
654 if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) {
|
|
|
655 debug_only(warning("os::uncommit_memory failed"));
|
|
|
656 return;
|
|
|
657 } else {
|
|
|
658 _middle_high -= middle_needs;
|
|
|
659 }
|
|
|
660 }
|
|
|
661 if (lower_needs > 0) {
|
|
|
662 assert(low_boundary() <= aligned_lower_new_high &&
|
|
|
663 aligned_lower_new_high + lower_needs <= lower_high_boundary(),
|
|
|
664 "must not shrink beyond region");
|
|
|
665 if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) {
|
|
|
666 debug_only(warning("os::uncommit_memory failed"));
|
|
|
667 return;
|
|
|
668 } else {
|
|
|
669 _lower_high -= lower_needs;
|
|
|
670 }
|
|
|
671 }
|
|
|
672
|
|
|
673 _high -= size;
|
|
|
674 }
|
|
|
675
|
|
|
676 #ifndef PRODUCT
|
|
|
677 void VirtualSpace::check_for_contiguity() {
|
|
|
678 // Check contiguity.
|
|
|
679 assert(low_boundary() <= lower_high() &&
|
|
|
680 lower_high() <= lower_high_boundary(),
|
|
|
681 "high address must be contained within the region");
|
|
|
682 assert(lower_high_boundary() <= middle_high() &&
|
|
|
683 middle_high() <= middle_high_boundary(),
|
|
|
684 "high address must be contained within the region");
|
|
|
685 assert(middle_high_boundary() <= upper_high() &&
|
|
|
686 upper_high() <= upper_high_boundary(),
|
|
|
687 "high address must be contained within the region");
|
|
|
688 assert(low() >= low_boundary(), "low");
|
|
|
689 assert(low_boundary() <= lower_high_boundary(), "lower high boundary");
|
|
|
690 assert(upper_high_boundary() <= high_boundary(), "upper high boundary");
|
|
|
691 assert(high() <= upper_high(), "upper high");
|
|
|
692 }
|
|
|
693
|
|
|
694 void VirtualSpace::print() {
|
|
|
695 tty->print ("Virtual space:");
|
|
|
696 if (special()) tty->print(" (pinned in memory)");
|
|
|
697 tty->cr();
|
|
|
698 tty->print_cr(" - committed: %ld", committed_size());
|
|
|
699 tty->print_cr(" - reserved: %ld", reserved_size());
|
|
|
700 tty->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low(), high());
|
|
|
701 tty->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low_boundary(), high_boundary());
|
|
|
702 }
|
|
|
703
|
|
|
704 #endif
|
