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