1 /*
2 * Copyright (c) 2014, 2018, 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/g1PageBasedVirtualSpace.hpp"
27 #include "gc/shared/workgroup.hpp"
28 #include "oops/markOop.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "runtime/atomic.hpp"
31 #include "runtime/os.inline.hpp"
32 #include "services/memTracker.hpp"
33 #include "utilities/align.hpp"
34 #include "utilities/bitMap.inline.hpp"
35
36 G1PageBasedVirtualSpace::G1PageBasedVirtualSpace(ReservedSpace rs, size_t used_size, size_t page_size) :
37 _low_boundary(NULL), _high_boundary(NULL), _committed(mtGC), _page_size(0), _special(false),
38 _dirty(mtGC), _executable(false) {
39 initialize_with_page_size(rs, used_size, page_size);
40 }
41
42 void G1PageBasedVirtualSpace::initialize_with_page_size(ReservedSpace rs, size_t used_size, size_t page_size) {
43 guarantee(rs.is_reserved(), "Given reserved space must have been reserved already.");
44
45 vmassert(_low_boundary == NULL, "VirtualSpace already initialized");
46 vmassert(page_size > 0, "Page size must be non-zero.");
47
48 guarantee(is_aligned(rs.base(), page_size),
49 "Reserved space base " PTR_FORMAT " is not aligned to requested page size " SIZE_FORMAT, p2i(rs.base()), page_size);
50 guarantee(is_aligned(used_size, os::vm_page_size()),
51 "Given used reserved space size needs to be OS page size aligned (%d bytes) but is " SIZE_FORMAT, os::vm_page_size(), used_size);
52 guarantee(used_size <= rs.size(),
53 "Used size of reserved space " SIZE_FORMAT " bytes is smaller than reservation at " SIZE_FORMAT " bytes", used_size, rs.size());
54 guarantee(is_aligned(rs.size(), page_size),
55 "Expected that the virtual space is size aligned, but " SIZE_FORMAT " is not aligned to page size " SIZE_FORMAT, rs.size(), page_size);
56
57 _low_boundary = rs.base();
58 _high_boundary = _low_boundary + used_size;
59
60 _special = rs.special();
61 _executable = rs.executable();
62
63 _page_size = page_size;
64
65 vmassert(_committed.size() == 0, "virtual space initialized more than once");
66 BitMap::idx_t size_in_pages = rs.size() / page_size;
67 _committed.initialize(size_in_pages);
68 if (_special) {
69 _dirty.initialize(size_in_pages);
70 }
71
72 _tail_size = used_size % _page_size;
73 }
74
75 G1PageBasedVirtualSpace::~G1PageBasedVirtualSpace() {
76 // This does not release memory it never reserved.
77 // Caller must release via rs.release();
78 _low_boundary = NULL;
79 _high_boundary = NULL;
80 _special = false;
81 _executable = false;
82 _page_size = 0;
83 _tail_size = 0;
84 }
85
86 size_t G1PageBasedVirtualSpace::committed_size() const {
87 size_t result = _committed.count_one_bits() * _page_size;
88 // The last page might not be in full.
89 if (is_last_page_partial() && _committed.at(_committed.size() - 1)) {
90 result -= _page_size - _tail_size;
91 }
92 return result;
93 }
94
95 size_t G1PageBasedVirtualSpace::reserved_size() const {
96 return pointer_delta(_high_boundary, _low_boundary, sizeof(char));
97 }
98
99 size_t G1PageBasedVirtualSpace::uncommitted_size() const {
100 return reserved_size() - committed_size();
101 }
102
103 size_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const {
104 return (addr - _low_boundary) / _page_size;
105 }
106
107 bool G1PageBasedVirtualSpace::is_area_committed(size_t start_page, size_t size_in_pages) const {
108 size_t end_page = start_page + size_in_pages;
109 return _committed.get_next_zero_offset(start_page, end_page) >= end_page;
110 }
111
112 bool G1PageBasedVirtualSpace::is_area_uncommitted(size_t start_page, size_t size_in_pages) const {
113 size_t end_page = start_page + size_in_pages;
114 return _committed.get_next_one_offset(start_page, end_page) >= end_page;
115 }
116
117 char* G1PageBasedVirtualSpace::page_start(size_t index) const {
118 return _low_boundary + index * _page_size;
119 }
120
121 bool G1PageBasedVirtualSpace::is_after_last_page(size_t index) const {
122 guarantee(index <= _committed.size(),
123 "Given boundary page " SIZE_FORMAT " is beyond managed page count " SIZE_FORMAT, index, _committed.size());
124 return index == _committed.size();
125 }
126
127 // Setsup NVDIMM to Max oldgen Size allowed.
128 size_t G1PageBasedVirtualSpace::get_nvdimm_size() {
129 size_t size = reserved_size();
130 uint nvdimm_max_percent = 100 - G1MaxNewSizePercent;
131 size_t nvdimm_size = (size_t)((size * nvdimm_max_percent)/100);
132 size_t page_sz = os::vm_page_size() -1 ;
133 nvdimm_size = (nvdimm_size + page_sz) & (~page_sz);
134 nvdimm_size = align_up(nvdimm_size, HeapRegion::GrainBytes);
135 return nvdimm_size;
136 }
137
138 void G1PageBasedVirtualSpace::commit_preferred_pages(size_t start, size_t num_pages) {
139 vmassert(num_pages > 0, "No full pages to commit");
140 vmassert(start + num_pages <= _committed.size(),
141 "Tried to commit area from page " SIZE_FORMAT " to page " SIZE_FORMAT " "
142 "that is outside of managed space of " SIZE_FORMAT " pages",
143 start, start + num_pages, _committed.size());
144
145 char* start_addr = page_start(start);
146 size_t size = num_pages * _page_size;
147 if (((address)start_addr == (address)os::nvdimm_heapbase())) {
148 bool is_committed = os::commit_memory(start_addr, size, false, os::nvdimm_fd());
149 if (!is_committed) {
150 vm_exit_during_initialization(
151 err_msg("Could not map memory at %p for NVDIMM %s Fd %d", start_addr, AllocateOldGenAt, os::nvdimm_fd()));
152 } else {
153 log_info(gc, heap)("NVDIMM Memory successfully mapped at %p, Size %lu", start_addr, size);
154 os::close(os::nvdimm_fd());
155 }
156 size_t nvdimm_size = get_nvdimm_size();
157 char* dram_base = (char*)start_addr + nvdimm_size;
158 size_t total_sz = reserved_size();
159 os::set_dram_heapbase((address)dram_base);
160 log_info(gc, heap)("Java DRAM Heap at [%p - %p] & NVDIMM Old Gen at [%p - %p] Total Heap Sz %ld \n",
161 start_addr+nvdimm_size, (char*)(start_addr + total_sz), start_addr, (char*)(start_addr + nvdimm_size), total_sz);
162
163 return;
164 }
165 os::commit_memory_or_exit(start_addr, size, _page_size, _executable,
166 err_msg("Failed to commit area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
167 p2i(start_addr), p2i(start_addr + size), size));
168 }
169
170 void G1PageBasedVirtualSpace::commit_tail() {
171 vmassert(_tail_size > 0, "The size of the tail area must be > 0 when reaching here");
172
173 char* const aligned_end_address = align_down(_high_boundary, _page_size);
174 os::commit_memory_or_exit(aligned_end_address, _tail_size, os::vm_page_size(), _executable,
175 err_msg("Failed to commit tail area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
176 p2i(aligned_end_address), p2i(_high_boundary), _tail_size));
177 }
178
179 void G1PageBasedVirtualSpace::commit_internal(size_t start_page, size_t end_page) {
180 guarantee(start_page < end_page,
181 "Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page);
182 guarantee(end_page <= _committed.size(),
183 "Given end page " SIZE_FORMAT " is beyond end of managed page amount of " SIZE_FORMAT, end_page, _committed.size());
184
185 size_t pages = end_page - start_page;
186 bool need_to_commit_tail = is_after_last_page(end_page) && is_last_page_partial();
187
188 // If we have to commit some (partial) tail area, decrease the amount of pages to avoid
189 // committing that in the full-page commit code.
190 if (need_to_commit_tail) {
191 pages--;
192 }
193
194 if (pages > 0) {
195 commit_preferred_pages(start_page, pages);
196 }
197
198 if (need_to_commit_tail) {
199 commit_tail();
200 }
201 }
202
203 char* G1PageBasedVirtualSpace::bounded_end_addr(size_t end_page) const {
204 return MIN2(_high_boundary, page_start(end_page));
205 }
206
207 void G1PageBasedVirtualSpace::pretouch_internal(size_t start_page, size_t end_page) {
208 guarantee(start_page < end_page,
209 "Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page);
210
211 os::pretouch_memory(page_start(start_page), bounded_end_addr(end_page), _page_size);
212 }
213
214 bool G1PageBasedVirtualSpace::commit(size_t start_page, size_t size_in_pages) {
215 // We need to make sure to commit all pages covered by the given area.
216 guarantee(is_area_uncommitted(start_page, size_in_pages), "Specified area is not uncommitted");
217
218 bool zero_filled = true;
219 size_t end_page = start_page + size_in_pages;
220
221 if (_special) {
222 // Check for dirty pages and update zero_filled if any found.
223 if (_dirty.get_next_one_offset(start_page, end_page) < end_page) {
224 zero_filled = false;
225 _dirty.clear_range(start_page, end_page);
226 }
227 } else {
228 commit_internal(start_page, end_page);
229 }
230 _committed.set_range(start_page, end_page);
231
232 return zero_filled;
233 }
234
235 void G1PageBasedVirtualSpace::uncommit_internal(size_t start_page, size_t end_page) {
236 guarantee(start_page < end_page,
237 "Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page);
238
239 char* start_addr = page_start(start_page);
240 os::uncommit_memory(start_addr, pointer_delta(bounded_end_addr(end_page), start_addr, sizeof(char)));
241 }
242
243 void G1PageBasedVirtualSpace::uncommit(size_t start_page, size_t size_in_pages) {
244 guarantee(is_area_committed(start_page, size_in_pages), "checking");
245
246 size_t end_page = start_page + size_in_pages;
247 if (_special) {
248 // Mark that memory is dirty. If committed again the memory might
249 // need to be cleared explicitly.
250 _dirty.set_range(start_page, end_page);
251 } else {
252 uncommit_internal(start_page, end_page);
253 }
254
255 _committed.clear_range(start_page, end_page);
256 }
257
258 class G1PretouchTask : public AbstractGangTask {
259 private:
260 char* volatile _cur_addr;
261 char* const _start_addr;
262 char* const _end_addr;
263 size_t const _page_size;
264 public:
265 G1PretouchTask(char* start_address, char* end_address, size_t page_size) :
266 AbstractGangTask("G1 PreTouch"),
267 _cur_addr(start_address),
268 _start_addr(start_address),
269 _end_addr(end_address),
270 _page_size(page_size) {
271 }
272
273 virtual void work(uint worker_id) {
274 size_t const actual_chunk_size = MAX2(chunk_size(), _page_size);
275 while (true) {
276 char* touch_addr = Atomic::add(actual_chunk_size, &_cur_addr) - actual_chunk_size;
277 if (touch_addr < _start_addr || touch_addr >= _end_addr) {
278 break;
279 }
280 char* end_addr = touch_addr + MIN2(actual_chunk_size, pointer_delta(_end_addr, touch_addr, sizeof(char)));
281 os::pretouch_memory(touch_addr, end_addr, _page_size);
282 }
283 }
284
285 static size_t chunk_size() { return PreTouchParallelChunkSize; }
286 };
287
288 void G1PageBasedVirtualSpace::pretouch(size_t start_page, size_t size_in_pages, WorkGang* pretouch_gang) {
289 G1PretouchTask cl(page_start(start_page), bounded_end_addr(start_page + size_in_pages), _page_size);
290
291 if (pretouch_gang != NULL) {
292 size_t num_chunks = MAX2((size_t)1, size_in_pages * _page_size / MAX2(G1PretouchTask::chunk_size(), _page_size));
293
294 uint num_workers = MIN2((uint)num_chunks, pretouch_gang->active_workers());
295 log_debug(gc, heap)("Running %s with %u workers for " SIZE_FORMAT " work units pre-touching " SIZE_FORMAT "B.",
296 cl.name(), num_workers, num_chunks, size_in_pages * _page_size);
297 pretouch_gang->run_task(&cl, num_workers);
298 } else {
299 log_debug(gc, heap)("Running %s pre-touching " SIZE_FORMAT "B.",
300 cl.name(), size_in_pages * _page_size);
301 cl.work(0);
302 }
303 }
304
305 bool G1PageBasedVirtualSpace::contains(const void* p) const {
306 return _low_boundary <= (const char*) p && (const char*) p < _high_boundary;
307 }
308
309 #ifndef PRODUCT
310 void G1PageBasedVirtualSpace::print_on(outputStream* out) {
311 out->print ("Virtual space:");
312 if (_special) out->print(" (pinned in memory)");
313 out->cr();
314 out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
315 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
316 out->print_cr(" - preferred page size: " SIZE_FORMAT, _page_size);
317 out->print_cr(" - [low_b, high_b]: [" PTR_FORMAT ", " PTR_FORMAT "]", p2i(_low_boundary), p2i(_high_boundary));
318 }
319
320 void G1PageBasedVirtualSpace::print() {
321 print_on(tty);
322 }
323 #endif