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