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