rev 47399 : [mq]: add_ptr
1 /*
2 * Copyright (c) 2014, 2017, 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 void G1PageBasedVirtualSpace::commit_preferred_pages(size_t start, size_t num_pages) {
128 vmassert(num_pages > 0, "No full pages to commit");
129 vmassert(start + num_pages <= _committed.size(),
130 "Tried to commit area from page " SIZE_FORMAT " to page " SIZE_FORMAT " "
131 "that is outside of managed space of " SIZE_FORMAT " pages",
132 start, start + num_pages, _committed.size());
133
134 char* start_addr = page_start(start);
135 size_t size = num_pages * _page_size;
136
137 os::commit_memory_or_exit(start_addr, size, _page_size, _executable,
138 err_msg("Failed to commit area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
139 p2i(start_addr), p2i(start_addr + size), size));
140 }
141
142 void G1PageBasedVirtualSpace::commit_tail() {
143 vmassert(_tail_size > 0, "The size of the tail area must be > 0 when reaching here");
144
145 char* const aligned_end_address = align_down(_high_boundary, _page_size);
146 os::commit_memory_or_exit(aligned_end_address, _tail_size, os::vm_page_size(), _executable,
147 err_msg("Failed to commit tail area from " PTR_FORMAT " to " PTR_FORMAT " of length " SIZE_FORMAT ".",
148 p2i(aligned_end_address), p2i(_high_boundary), _tail_size));
149 }
150
151 void G1PageBasedVirtualSpace::commit_internal(size_t start_page, size_t end_page) {
152 guarantee(start_page < end_page,
153 "Given start page " SIZE_FORMAT " is larger or equal to end page " SIZE_FORMAT, start_page, end_page);
154 guarantee(end_page <= _committed.size(),
155 "Given end page " SIZE_FORMAT " is beyond end of managed page amount of " SIZE_FORMAT, end_page, _committed.size());
156
157 size_t pages = end_page - start_page;
158 bool need_to_commit_tail = is_after_last_page(end_page) && is_last_page_partial();
159
160 // If we have to commit some (partial) tail area, decrease the amount of pages to avoid
161 // committing that in the full-page commit code.
162 if (need_to_commit_tail) {
163 pages--;
164 }
165
166 if (pages > 0) {
167 commit_preferred_pages(start_page, pages);
168 }
169
170 if (need_to_commit_tail) {
171 commit_tail();
172 }
173 }
174
175 char* G1PageBasedVirtualSpace::bounded_end_addr(size_t end_page) const {
176 return MIN2(_high_boundary, page_start(end_page));
177 }
178
179 void G1PageBasedVirtualSpace::pretouch_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
183 os::pretouch_memory(page_start(start_page), bounded_end_addr(end_page), _page_size);
184 }
185
186 bool G1PageBasedVirtualSpace::commit(size_t start_page, size_t size_in_pages) {
187 // We need to make sure to commit all pages covered by the given area.
188 guarantee(is_area_uncommitted(start_page, size_in_pages), "Specified area is not uncommitted");
189
190 bool zero_filled = true;
191 size_t end_page = start_page + size_in_pages;
192
193 if (_special) {
194 // Check for dirty pages and update zero_filled if any found.
195 if (_dirty.get_next_one_offset(start_page, end_page) < end_page) {
196 zero_filled = false;
197 _dirty.clear_range(start_page, end_page);
198 }
199 } else {
200 commit_internal(start_page, end_page);
201 }
202 _committed.set_range(start_page, end_page);
203
204 return zero_filled;
205 }
206
207 void G1PageBasedVirtualSpace::uncommit_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 char* start_addr = page_start(start_page);
212 os::uncommit_memory(start_addr, pointer_delta(bounded_end_addr(end_page), start_addr, sizeof(char)));
213 }
214
215 void G1PageBasedVirtualSpace::uncommit(size_t start_page, size_t size_in_pages) {
216 guarantee(is_area_committed(start_page, size_in_pages), "checking");
217
218 size_t end_page = start_page + size_in_pages;
219 if (_special) {
220 // Mark that memory is dirty. If committed again the memory might
221 // need to be cleared explicitly.
222 _dirty.set_range(start_page, end_page);
223 } else {
224 uncommit_internal(start_page, end_page);
225 }
226
227 _committed.clear_range(start_page, end_page);
228 }
229
230 class G1PretouchTask : public AbstractGangTask {
231 private:
232 char* volatile _cur_addr;
233 char* const _start_addr;
234 char* const _end_addr;
235 size_t const _page_size;
236 public:
237 G1PretouchTask(char* start_address, char* end_address, size_t page_size) :
238 AbstractGangTask("G1 PreTouch",
239 Universe::is_fully_initialized() &&
240 Thread::current()->is_Named_thread() ? GCId::current_raw() :
241 // During VM initialization there is
242 // no GC cycle that this task can be
243 // associated with.
244 GCId::undefined()),
245 _cur_addr(start_address),
246 _start_addr(start_address),
247 _end_addr(end_address),
248 _page_size(page_size) {
249 }
250
251 virtual void work(uint worker_id) {
252 size_t const actual_chunk_size = MAX2(chunk_size(), _page_size);
253 while (true) {
254 char* touch_addr = (char*)Atomic::add_ptr((intptr_t)actual_chunk_size, (volatile void*) &_cur_addr) - actual_chunk_size;
255 if (touch_addr < _start_addr || touch_addr >= _end_addr) {
256 break;
257 }
258 char* end_addr = touch_addr + MIN2(actual_chunk_size, pointer_delta(_end_addr, touch_addr, sizeof(char)));
259 os::pretouch_memory(touch_addr, end_addr, _page_size);
260 }
261 }
262
263 static size_t chunk_size() { return PreTouchParallelChunkSize; }
264 };
265
266 void G1PageBasedVirtualSpace::pretouch(size_t start_page, size_t size_in_pages, WorkGang* pretouch_gang) {
267 G1PretouchTask cl(page_start(start_page), bounded_end_addr(start_page + size_in_pages), _page_size);
268
269 if (pretouch_gang != NULL) {
270 size_t num_chunks = MAX2((size_t)1, size_in_pages * _page_size / MAX2(G1PretouchTask::chunk_size(), _page_size));
271
272 uint num_workers = MIN2((uint)num_chunks, pretouch_gang->active_workers());
273 log_debug(gc, heap)("Running %s with %u workers for " SIZE_FORMAT " work units pre-touching " SIZE_FORMAT "B.",
274 cl.name(), num_workers, num_chunks, size_in_pages * _page_size);
275 pretouch_gang->run_task(&cl, num_workers);
276 } else {
277 log_debug(gc, heap)("Running %s pre-touching " SIZE_FORMAT "B.",
278 cl.name(), size_in_pages * _page_size);
279 cl.work(0);
280 }
281 }
282
283 bool G1PageBasedVirtualSpace::contains(const void* p) const {
284 return _low_boundary <= (const char*) p && (const char*) p < _high_boundary;
285 }
286
287 #ifndef PRODUCT
288 void G1PageBasedVirtualSpace::print_on(outputStream* out) {
289 out->print ("Virtual space:");
290 if (_special) out->print(" (pinned in memory)");
291 out->cr();
292 out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
293 out->print_cr(" - reserved: " SIZE_FORMAT, reserved_size());
294 out->print_cr(" - preferred page size: " SIZE_FORMAT, _page_size);
295 out->print_cr(" - [low_b, high_b]: [" PTR_FORMAT ", " PTR_FORMAT "]", p2i(_low_boundary), p2i(_high_boundary));
296 }
297
298 void G1PageBasedVirtualSpace::print() {
299 print_on(tty);
300 }
301 #endif
--- EOF ---