1 /* 2 * Copyright (c) 2014, 2015, 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 #include "precompiled.hpp" 26 #include "gc_implementation/g1/g1PageBasedVirtualSpace.hpp" 27 #include "oops/markOop.hpp" 28 #include "oops/oop.inline.hpp" 29 #include "services/memTracker.hpp" 30 #ifdef TARGET_OS_FAMILY_linux 31 # include "os_linux.inline.hpp" 32 #endif 33 #ifdef TARGET_OS_FAMILY_solaris 34 # include "os_solaris.inline.hpp" 35 #endif 36 #ifdef TARGET_OS_FAMILY_windows 37 # include "os_windows.inline.hpp" 38 #endif 39 #ifdef TARGET_OS_FAMILY_aix 40 # include "os_aix.inline.hpp" 41 #endif 42 #ifdef TARGET_OS_FAMILY_bsd 43 # include "os_bsd.inline.hpp" 44 #endif 45 #include "utilities/bitMap.inline.hpp" 46 47 G1PageBasedVirtualSpace::G1PageBasedVirtualSpace(ReservedSpace rs, size_t used_size, size_t page_size) : 48 _low_boundary(NULL), _high_boundary(NULL), _committed(), _page_size(0), _special(false), 49 _dirty(), _executable(false) { 50 initialize_with_page_size(rs, used_size, page_size); 51 } 52 53 void G1PageBasedVirtualSpace::initialize_with_page_size(ReservedSpace rs, size_t used_size, size_t page_size) { 54 guarantee(rs.is_reserved(), "Given reserved space must have been reserved already."); 55 56 vmassert(_low_boundary == NULL, "VirtualSpace already initialized"); 57 vmassert(page_size > 0, "Page size must be non-zero."); 58 59 guarantee(is_ptr_aligned(rs.base(), page_size), 60 err_msg("Reserved space base " PTR_FORMAT " is not aligned to requested page size " SIZE_FORMAT, p2i(rs.base()), page_size)); 61 guarantee(is_size_aligned(used_size, os::vm_page_size()), 62 err_msg("Given used reserved space size needs to be OS page size aligned (%d bytes) but is " SIZE_FORMAT, os::vm_page_size(), used_size)); 63 guarantee(used_size <= rs.size(), 64 err_msg("Used size of reserved space " SIZE_FORMAT " bytes is smaller than reservation at " SIZE_FORMAT " bytes", used_size, rs.size())); 65 guarantee(is_size_aligned(rs.size(), page_size), 66 err_msg("Expected that the virtual space is size aligned, but " SIZE_FORMAT " is not aligned to page size " SIZE_FORMAT, rs.size(), page_size)); 67 68 _low_boundary = rs.base(); 69 _high_boundary = _low_boundary + used_size; 70 71 _special = rs.special(); 72 _executable = rs.executable(); 73 74 _page_size = page_size; 75 76 vmassert(_committed.size() == 0, "virtual space initialized more than once"); 77 BitMap::idx_t size_in_pages = rs.size() / page_size; 78 _committed.resize(size_in_pages, /* in_resource_area */ false); 79 if (_special) { 80 _dirty.resize(size_in_pages, /* in_resource_area */ false); 81 } 82 } 83 84 G1PageBasedVirtualSpace::~G1PageBasedVirtualSpace() { 85 release(); 86 } 87 88 void G1PageBasedVirtualSpace::release() { 89 // This does not release memory it never reserved. 90 // Caller must release via rs.release(); 91 _low_boundary = NULL; 92 _high_boundary = NULL; 93 _special = false; 94 _executable = false; 95 _page_size = 0; 96 _committed.resize(0, false); 97 _dirty.resize(0, false); 98 } 99 100 size_t G1PageBasedVirtualSpace::committed_size() const { 101 size_t result = _committed.count_one_bits() * _page_size; 102 // The last page might not be in full. 103 if (_committed.at(_committed.size() - 1)) { 104 char* aligned_high_boundary = (char*)align_ptr_up(_high_boundary, _page_size); 105 result -= pointer_delta(aligned_high_boundary, _high_boundary, sizeof(char)); 106 } 107 return result; 108 } 109 110 size_t G1PageBasedVirtualSpace::reserved_size() const { 111 return pointer_delta(_high_boundary, _low_boundary, sizeof(char)); 112 } 113 114 size_t G1PageBasedVirtualSpace::uncommitted_size() const { 115 return reserved_size() - committed_size(); 116 } 117 118 size_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const { 119 return (addr - _low_boundary) / _page_size; 120 } 121 122 bool G1PageBasedVirtualSpace::is_area_committed(size_t start, size_t size_in_pages) const { 123 size_t end = start + size_in_pages; 124 return _committed.get_next_zero_offset(start, end) >= end; 125 } 126 127 bool G1PageBasedVirtualSpace::is_area_uncommitted(size_t start, size_t size_in_pages) const { 128 size_t end = start + size_in_pages; 129 return _committed.get_next_one_offset(start, end) >= end; 130 } 131 132 char* G1PageBasedVirtualSpace::page_start(size_t index) { 133 return _low_boundary + index * _page_size; 134 } 135 136 bool G1PageBasedVirtualSpace::is_after_last_page(size_t index) { 137 guarantee(index <= _committed.size(), 138 err_msg("Given boundary page " SIZE_FORMAT " is beyond managed page count " SIZE_FORMAT, index, _committed.size())); 139 return index == _committed.size(); 140 } 141 142 void G1PageBasedVirtualSpace::commit_full_pages(size_t start, size_t num_pages) { 143 vmassert(num_pages > 0, "No full pages to commit"); 144 vmassert(start + num_pages <= _committed.size(), 145 err_msg("Tried to commit area from page " SIZE_FORMAT " to page " SIZE_FORMAT " " 146 "that is outside of managed space of " SIZE_FORMAT " pages", 147 start, start + num_pages, _committed.size())); 148 149 char* start_addr = page_start(start); 150 size_t size = num_pages * _page_size; 151 152 os::commit_memory_or_exit(start_addr, size, _page_size, _executable, 153 err_msg("Failed to commit area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".", 154 p2i(start_addr), p2i(start_addr + size), size)); 155 } 156 157 void G1PageBasedVirtualSpace::commit_tail() { 158 char* const aligned_end_address = (char*)align_ptr_down(_high_boundary, _page_size); 159 size_t const tail_size = pointer_delta(_high_boundary, aligned_end_address, sizeof(char)); 160 161 os::commit_memory_or_exit(aligned_end_address, tail_size, os::vm_page_size(), _executable, 162 err_msg("Failed to commit tail area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".", 163 p2i(aligned_end_address), p2i(_high_boundary), tail_size)); 164 } 165 166 void G1PageBasedVirtualSpace::commit_internal(size_t start_page, size_t end_page) { 167 guarantee(start_page < end_page, 168 err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page)); 169 guarantee(end_page <= _committed.size(), 170 err_msg("Given end page " SIZE_FORMAT " is beyond end of managed page amount of " SIZE_FORMAT, end_page, _committed.size())); 171 172 size_t pages = end_page - start_page; 173 bool need_to_commit_tail = is_after_last_page(end_page) && is_last_page_partial(); 174 175 // If we have to commit some (partial) tail area, decrease the amount of pages to avoid 176 // committing that in the full-page commit code. 177 if (need_to_commit_tail) { 178 pages--; 179 } 180 181 if (pages > 0) { 182 commit_full_pages(start_page, pages); 183 } 184 185 if (need_to_commit_tail) { 186 commit_tail(); 187 } 188 } 189 190 char* G1PageBasedVirtualSpace::bounded_end_addr(size_t end_page) { 191 return MIN2(_high_boundary, page_start(end_page)); 192 } 193 194 void G1PageBasedVirtualSpace::pretouch_internal(size_t start_page, size_t end_page) { 195 guarantee(start_page < end_page, 196 err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page)); 197 198 os::pretouch_memory(page_start(start_page), bounded_end_addr(end_page)); 199 } 200 201 bool G1PageBasedVirtualSpace::commit(size_t start, size_t size_in_pages) { 202 // We need to make sure to commit all pages covered by the given area. 203 guarantee(is_area_uncommitted(start, size_in_pages), "Specified area is not uncommitted"); 204 205 bool zero_filled = true; 206 size_t end = start + size_in_pages; 207 208 if (_special) { 209 // Check for dirty pages and update zero_filled if any found. 210 if (_dirty.get_next_one_offset(start, end) < end) { 211 zero_filled = false; 212 _dirty.clear_range(start, end); 213 } 214 } else { 215 commit_internal(start, end); 216 } 217 _committed.set_range(start, end); 218 219 if (AlwaysPreTouch) { 220 pretouch_internal(start, end); 221 } 222 return zero_filled; 223 } 224 225 void G1PageBasedVirtualSpace::uncommit_internal(size_t start_page, size_t end_page) { 226 guarantee(start_page < end_page, 227 err_msg("Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page)); 228 229 char* start_addr = page_start(start_page); 230 os::uncommit_memory(start_addr, pointer_delta(bounded_end_addr(end_page), start_addr, sizeof(char))); 231 } 232 233 void G1PageBasedVirtualSpace::uncommit(size_t start, size_t size_in_pages) { 234 guarantee(is_area_committed(start, size_in_pages), "checking"); 235 236 size_t end = start + size_in_pages; 237 if (_special) { 238 // Mark that memory is dirty. If committed again the memory might 239 // need to be cleared explicitly. 240 _dirty.set_range(start, end); 241 } else { 242 uncommit_internal(start, end); 243 } 244 245 _committed.clear_range(start, end); 246 } 247 248 bool G1PageBasedVirtualSpace::contains(const void* p) const { 249 return _low_boundary <= (const char*) p && (const char*) p < _high_boundary; 250 } 251 252 #ifndef PRODUCT 253 void G1PageBasedVirtualSpace::print_on(outputStream* out) { 254 out->print ("Virtual space:"); 255 if (_special) out->print(" (pinned in memory)"); 256 out->cr(); 257 out->print_cr(" - committed: " SIZE_FORMAT, committed_size()); 258 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size()); 259 out->print_cr(" - preferred page size: " SIZE_FORMAT, _page_size); 260 out->print_cr(" - [low_b, high_b]: [" PTR_FORMAT ", " PTR_FORMAT "]", p2i(_low_boundary), p2i(_high_boundary)); 261 } 262 263 void G1PageBasedVirtualSpace::print() { 264 print_on(tty); 265 } 266 #endif