1 /* 2 * Copyright (c) 2001, 2019, 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/g1/g1BiasedArray.hpp" 27 #include "gc/g1/g1NUMA.hpp" 28 #include "gc/g1/g1RegionToSpaceMapper.hpp" 29 #include "logging/log.hpp" 30 #include "memory/allocation.inline.hpp" 31 #include "memory/virtualspace.hpp" 32 #include "runtime/java.hpp" 33 #include "runtime/os.inline.hpp" 34 #include "services/memTracker.hpp" 35 #include "utilities/align.hpp" 36 #include "utilities/bitMap.inline.hpp" 37 #include "utilities/formatBuffer.hpp" 38 39 G1RegionToSpaceMapper::G1RegionToSpaceMapper(ReservedSpace rs, 40 size_t used_size, 41 size_t page_size, 42 size_t region_granularity, 43 size_t commit_factor, 44 MemoryType type) : 45 _listener(NULL), 46 _storage(rs, used_size, page_size), 47 _region_granularity(region_granularity), 48 _commit_map(rs.size() * commit_factor / region_granularity, mtGC), 49 _memory_type(type) { 50 guarantee(is_power_of_2(page_size), "must be"); 51 guarantee(is_power_of_2(region_granularity), "must be"); 52 53 MemTracker::record_virtual_memory_type((address)rs.base(), type); 54 } 55 56 // G1RegionToSpaceMapper implementation where the region granularity is larger than 57 // or the same as the commit granularity. 58 // Basically, the space corresponding to one region region spans several OS pages. 59 class G1RegionsLargerThanCommitSizeMapper : public G1RegionToSpaceMapper { 60 private: 61 size_t _pages_per_region; 62 63 public: 64 G1RegionsLargerThanCommitSizeMapper(ReservedSpace rs, 65 size_t actual_size, 66 size_t page_size, 67 size_t alloc_granularity, 68 size_t commit_factor, 69 MemoryType type) : 70 G1RegionToSpaceMapper(rs, actual_size, page_size, alloc_granularity, commit_factor, type), 71 _pages_per_region(alloc_granularity / (page_size * commit_factor)) { 72 73 guarantee(alloc_granularity >= page_size, "allocation granularity smaller than commit granularity"); 74 } 75 76 virtual void commit_regions(uint start_idx, size_t num_regions, WorkGang* pretouch_gang) { 77 const size_t start_page = (size_t)start_idx * _pages_per_region; 78 const size_t size_in_pages = num_regions * _pages_per_region; 79 bool zero_filled = _storage.commit(start_page, size_in_pages); 80 if (_memory_type == mtJavaHeap) { 81 for (uint region_index = start_idx; region_index < start_idx + num_regions; region_index++ ) { 82 void* address = _storage.page_start(region_index * _pages_per_region); 83 size_t size_in_bytes = _storage.page_size() * _pages_per_region; 84 G1NUMA::numa()->request_memory_on_node(address, size_in_bytes, region_index); 85 } 86 } 87 if (AlwaysPreTouch) { 88 _storage.pretouch(start_page, size_in_pages, pretouch_gang); 89 } 90 _commit_map.par_set_range(start_idx, start_idx + num_regions, BitMap::unknown_range); 91 fire_on_commit(start_idx, num_regions, zero_filled); 92 } 93 94 virtual void uncommit_regions(uint start_idx, size_t num_regions) { 95 _storage.uncommit((size_t)start_idx * _pages_per_region, num_regions * _pages_per_region); 96 _commit_map.par_clear_range(start_idx, start_idx + num_regions, BitMap::unknown_range); 97 } 98 99 virtual bool can_parallelly_commit_and_uncommit() const { 100 return !_storage.is_special(); 101 } 102 }; 103 104 // G1RegionToSpaceMapper implementation where the region granularity is smaller 105 // than the commit granularity. 106 // Basically, the contents of one OS page span several regions. 107 class G1RegionsSmallerThanCommitSizeMapper : public G1RegionToSpaceMapper { 108 private: 109 class CommitRefcountArray : public G1BiasedMappedArray<uint> { 110 protected: 111 virtual uint default_value() const { return 0; } 112 }; 113 114 size_t _regions_per_page; 115 116 CommitRefcountArray _refcounts; 117 118 uintptr_t region_idx_to_page_idx(uint region) const { 119 return region / _regions_per_page; 120 } 121 122 public: 123 G1RegionsSmallerThanCommitSizeMapper(ReservedSpace rs, 124 size_t actual_size, 125 size_t page_size, 126 size_t alloc_granularity, 127 size_t commit_factor, 128 MemoryType type) : 129 G1RegionToSpaceMapper(rs, actual_size, page_size, alloc_granularity, commit_factor, type), 130 _regions_per_page((page_size * commit_factor) / alloc_granularity), _refcounts() { 131 132 guarantee((page_size * commit_factor) >= alloc_granularity, "allocation granularity smaller than commit granularity"); 133 _refcounts.initialize((HeapWord*)rs.base(), (HeapWord*)(rs.base() + align_up(rs.size(), page_size)), page_size); 134 } 135 136 virtual void commit_regions(uint start_idx, size_t num_regions, WorkGang* pretouch_gang) { 137 size_t const NoPage = ~(size_t)0; 138 139 size_t first_committed = NoPage; 140 size_t num_committed = 0; 141 142 bool all_zero_filled = true; 143 G1NUMA* numa = G1NUMA::numa(); 144 145 for (uint region_idx = start_idx; region_idx < start_idx + num_regions; region_idx++) { 146 assert(!_commit_map.at(region_idx), "Trying to commit storage at region %u that is already committed", region_idx); 147 size_t page_idx = region_idx_to_page_idx(region_idx); 148 uint old_refcount = _refcounts.get_by_index(page_idx); 149 150 bool zero_filled = false; 151 if (old_refcount == 0) { 152 if (first_committed == NoPage) { 153 first_committed = page_idx; 154 num_committed = 1; 155 } else { 156 num_committed++; 157 } 158 zero_filled = _storage.commit(page_idx, 1); 159 if (_memory_type == mtJavaHeap) { 160 void* address = _storage.page_start(page_idx); 161 size_t size_in_bytes = _storage.page_size(); 162 numa->request_memory_on_node(address, size_in_bytes, region_idx); 163 } 164 } 165 all_zero_filled &= zero_filled; 166 167 _refcounts.set_by_index(page_idx, old_refcount + 1); 168 _commit_map.set_bit(region_idx); 169 } 170 if (AlwaysPreTouch && num_committed > 0) { 171 _storage.pretouch(first_committed, num_committed, pretouch_gang); 172 } 173 fire_on_commit(start_idx, num_regions, all_zero_filled); 174 } 175 176 virtual void uncommit_regions(uint start_idx, size_t num_regions) { 177 for (uint i = start_idx; i < start_idx + num_regions; i++) { 178 assert(_commit_map.at(i), "Trying to uncommit storage at region %u that is not committed", i); 179 size_t idx = region_idx_to_page_idx(i); 180 uint old_refcount = _refcounts.get_by_index(idx); 181 assert(old_refcount > 0, "must be"); 182 if (old_refcount == 1) { 183 _storage.uncommit(idx, 1); 184 } 185 _refcounts.set_by_index(idx, old_refcount - 1); 186 _commit_map.clear_bit(i); 187 } 188 } 189 190 virtual bool can_parallelly_commit_and_uncommit() const { 191 return false; 192 } 193 }; 194 195 void G1RegionToSpaceMapper::fire_on_commit(uint start_idx, size_t num_regions, bool zero_filled) { 196 if (_listener != NULL) { 197 _listener->on_commit(start_idx, num_regions, zero_filled); 198 } 199 } 200 201 static bool map_nvdimm_space(ReservedSpace rs) { 202 assert(AllocateOldGenAt != NULL, ""); 203 int _backing_fd = os::create_file_for_heap(AllocateOldGenAt); 204 if (_backing_fd == -1) { 205 log_error(gc, init)("Could not create file for Old generation at location %s", AllocateOldGenAt); 206 return false; 207 } 208 // commit this memory in nv-dimm 209 char* ret = os::attempt_reserve_memory_at(rs.size(), rs.base(), _backing_fd); 210 211 if (ret != rs.base()) { 212 if (ret != NULL) { 213 os::unmap_memory(rs.base(), rs.size()); 214 } 215 log_error(gc, init)("Error in mapping Old Gen to given AllocateOldGenAt = %s", AllocateOldGenAt); 216 os::close(_backing_fd); 217 return false; 218 } 219 220 os::close(_backing_fd); 221 return true; 222 } 223 224 G1RegionToHeteroSpaceMapper::G1RegionToHeteroSpaceMapper(ReservedSpace rs, 225 size_t actual_size, 226 size_t page_size, 227 size_t alloc_granularity, 228 size_t commit_factor, 229 MemoryType type) : 230 G1RegionToSpaceMapper(rs, actual_size, page_size, alloc_granularity, commit_factor, type), 231 _rs(rs), 232 _dram_mapper(NULL), 233 _num_committed_dram(0), 234 _num_committed_nvdimm(0), 235 _start_index_of_dram(0), 236 _page_size(page_size), 237 _commit_factor(commit_factor), 238 _type(type) { 239 assert(actual_size == 2 * MaxHeapSize, "For 2-way heterogenuous heap, reserved space is two times MaxHeapSize"); 240 } 241 242 bool G1RegionToHeteroSpaceMapper::initialize() { 243 // Since we need to re-map the reserved space - 'Xmx' to nv-dimm and 'Xmx' to dram, we need to release the reserved memory first. 244 // Because on some OSes (e.g. Windows) you cannot do a file mapping on memory reserved with regular mapping. 245 os::release_memory(_rs.base(), _rs.size()); 246 // First half of size Xmx is for nv-dimm. 247 ReservedSpace rs_nvdimm = _rs.first_part(MaxHeapSize); 248 assert(rs_nvdimm.base() == _rs.base(), "We should get the same base address"); 249 250 // Second half of reserved memory is mapped to dram. 251 ReservedSpace rs_dram = _rs.last_part(MaxHeapSize); 252 253 assert(rs_dram.size() == rs_nvdimm.size() && rs_nvdimm.size() == MaxHeapSize, "They all should be same"); 254 255 // Reserve dram memory 256 char* base = os::attempt_reserve_memory_at(rs_dram.size(), rs_dram.base()); 257 if (base != rs_dram.base()) { 258 if (base != NULL) { 259 os::release_memory(base, rs_dram.size()); 260 } 261 log_error(gc, init)("Error in re-mapping memory on dram during G1 heterogenous memory initialization"); 262 return false; 263 } 264 265 // We reserve and commit this entire space to NV-DIMM. 266 if (!map_nvdimm_space(rs_nvdimm)) { 267 log_error(gc, init)("Error in re-mapping memory to nv-dimm during G1 heterogenous memory initialization"); 268 return false; 269 } 270 271 if (_region_granularity >= (_page_size * _commit_factor)) { 272 _dram_mapper = new G1RegionsLargerThanCommitSizeMapper(rs_dram, rs_dram.size(), _page_size, _region_granularity, _commit_factor, _type); 273 } else { 274 _dram_mapper = new G1RegionsSmallerThanCommitSizeMapper(rs_dram, rs_dram.size(), _page_size, _region_granularity, _commit_factor, _type); 275 } 276 277 _start_index_of_dram = (uint)(rs_nvdimm.size() / _region_granularity); 278 return true; 279 } 280 281 void G1RegionToHeteroSpaceMapper::commit_regions(uint start_idx, size_t num_regions, WorkGang* pretouch_gang) { 282 uint end_idx = (start_idx + (uint)num_regions - 1); 283 284 uint num_dram = end_idx >= _start_index_of_dram ? MIN2((end_idx - _start_index_of_dram + 1), (uint)num_regions) : 0; 285 uint num_nvdimm = (uint)num_regions - num_dram; 286 287 if (num_nvdimm > 0) { 288 // We do not need to commit nv-dimm regions, since they are committed in the beginning. 289 _num_committed_nvdimm += num_nvdimm; 290 } 291 if (num_dram > 0) { 292 _dram_mapper->commit_regions(start_idx > _start_index_of_dram ? (start_idx - _start_index_of_dram) : 0, num_dram, pretouch_gang); 293 _num_committed_dram += num_dram; 294 } 295 } 296 297 void G1RegionToHeteroSpaceMapper::uncommit_regions(uint start_idx, size_t num_regions) { 298 uint end_idx = (start_idx + (uint)num_regions - 1); 299 uint num_dram = end_idx >= _start_index_of_dram ? MIN2((end_idx - _start_index_of_dram + 1), (uint)num_regions) : 0; 300 uint num_nvdimm = (uint)num_regions - num_dram; 301 302 if (num_nvdimm > 0) { 303 // We do not uncommit memory for nv-dimm regions. 304 _num_committed_nvdimm -= num_nvdimm; 305 } 306 307 if (num_dram > 0) { 308 _dram_mapper->uncommit_regions(start_idx > _start_index_of_dram ? (start_idx - _start_index_of_dram) : 0, num_dram); 309 _num_committed_dram -= num_dram; 310 } 311 } 312 313 bool G1RegionToHeteroSpaceMapper::can_parallelly_commit_and_uncommit() const { 314 return false; 315 } 316 317 uint G1RegionToHeteroSpaceMapper::num_committed_dram() const { 318 return _num_committed_dram; 319 } 320 321 uint G1RegionToHeteroSpaceMapper::num_committed_nvdimm() const { 322 return _num_committed_nvdimm; 323 } 324 325 G1RegionToSpaceMapper* G1RegionToSpaceMapper::create_heap_mapper(ReservedSpace rs, 326 size_t actual_size, 327 size_t page_size, 328 size_t region_granularity, 329 size_t commit_factor, 330 MemoryType type) { 331 if (AllocateOldGenAt != NULL) { 332 G1RegionToHeteroSpaceMapper* mapper = new G1RegionToHeteroSpaceMapper(rs, actual_size, page_size, region_granularity, commit_factor, type); 333 if (!mapper->initialize()) { 334 delete mapper; 335 return NULL; 336 } 337 return (G1RegionToSpaceMapper*)mapper; 338 } else { 339 return create_mapper(rs, actual_size, page_size, region_granularity, commit_factor, type); 340 } 341 } 342 343 G1RegionToSpaceMapper* G1RegionToSpaceMapper::create_mapper(ReservedSpace rs, 344 size_t actual_size, 345 size_t page_size, 346 size_t region_granularity, 347 size_t commit_factor, 348 MemoryType type) { 349 if (region_granularity >= (page_size * commit_factor)) { 350 return new G1RegionsLargerThanCommitSizeMapper(rs, actual_size, page_size, region_granularity, commit_factor, type); 351 } else { 352 return new G1RegionsSmallerThanCommitSizeMapper(rs, actual_size, page_size, region_granularity, commit_factor, type); 353 } 354 } 355 356 void G1RegionToSpaceMapper::commit_and_set_special() { 357 _storage.commit_and_set_special(); 358 }