Mercurial > hg > graal-compiler
annotate src/share/vm/runtime/virtualspace.cpp @ 6462:b3f5dc099f9d
removed XIR
author | Doug Simon <doug.simon@oracle.com> |
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date | Sun, 30 Sep 2012 13:21:20 +0200 |
parents | d2a62e0f25eb |
children | da91efe96a93 |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "oops/markOop.hpp" | |
27 #include "oops/oop.inline.hpp" | |
28 #include "runtime/virtualspace.hpp" | |
6197 | 29 #include "services/memTracker.hpp" |
1972 | 30 #ifdef TARGET_OS_FAMILY_linux |
31 # include "os_linux.inline.hpp" | |
32 #endif | |
33 #ifdef TARGET_OS_FAMILY_solaris | |
34 # include "os_solaris.inline.hpp" | |
35 #endif | |
36 #ifdef TARGET_OS_FAMILY_windows | |
37 # include "os_windows.inline.hpp" | |
38 #endif | |
3960 | 39 #ifdef TARGET_OS_FAMILY_bsd |
40 # include "os_bsd.inline.hpp" | |
41 #endif | |
0 | 42 |
43 | |
44 // ReservedSpace | |
45 ReservedSpace::ReservedSpace(size_t size) { | |
656 | 46 initialize(size, 0, false, NULL, 0, false); |
0 | 47 } |
48 | |
49 ReservedSpace::ReservedSpace(size_t size, size_t alignment, | |
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50 bool large, |
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51 char* requested_address, |
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52 const size_t noaccess_prefix) { |
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53 initialize(size+noaccess_prefix, alignment, large, requested_address, |
656 | 54 noaccess_prefix, false); |
55 } | |
56 | |
57 ReservedSpace::ReservedSpace(size_t size, size_t alignment, | |
58 bool large, | |
59 bool executable) { | |
60 initialize(size, alignment, large, NULL, 0, executable); | |
0 | 61 } |
62 | |
63 char * | |
64 ReservedSpace::align_reserved_region(char* addr, const size_t len, | |
65 const size_t prefix_size, | |
66 const size_t prefix_align, | |
67 const size_t suffix_size, | |
68 const size_t suffix_align) | |
69 { | |
70 assert(addr != NULL, "sanity"); | |
71 const size_t required_size = prefix_size + suffix_size; | |
72 assert(len >= required_size, "len too small"); | |
73 | |
74 const size_t s = size_t(addr); | |
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75 const size_t beg_ofs = (s + prefix_size) & (suffix_align - 1); |
0 | 76 const size_t beg_delta = beg_ofs == 0 ? 0 : suffix_align - beg_ofs; |
77 | |
78 if (len < beg_delta + required_size) { | |
79 return NULL; // Cannot do proper alignment. | |
80 } | |
81 const size_t end_delta = len - (beg_delta + required_size); | |
82 | |
83 if (beg_delta != 0) { | |
84 os::release_memory(addr, beg_delta); | |
85 } | |
86 | |
87 if (end_delta != 0) { | |
88 char* release_addr = (char*) (s + beg_delta + required_size); | |
89 os::release_memory(release_addr, end_delta); | |
90 } | |
91 | |
92 return (char*) (s + beg_delta); | |
93 } | |
94 | |
95 char* ReservedSpace::reserve_and_align(const size_t reserve_size, | |
96 const size_t prefix_size, | |
97 const size_t prefix_align, | |
98 const size_t suffix_size, | |
99 const size_t suffix_align) | |
100 { | |
101 assert(reserve_size > prefix_size + suffix_size, "should not be here"); | |
102 | |
103 char* raw_addr = os::reserve_memory(reserve_size, NULL, prefix_align); | |
104 if (raw_addr == NULL) return NULL; | |
105 | |
106 char* result = align_reserved_region(raw_addr, reserve_size, prefix_size, | |
107 prefix_align, suffix_size, | |
108 suffix_align); | |
109 if (result == NULL && !os::release_memory(raw_addr, reserve_size)) { | |
110 fatal("os::release_memory failed"); | |
111 } | |
112 | |
113 #ifdef ASSERT | |
114 if (result != NULL) { | |
115 const size_t raw = size_t(raw_addr); | |
116 const size_t res = size_t(result); | |
117 assert(res >= raw, "alignment decreased start addr"); | |
118 assert(res + prefix_size + suffix_size <= raw + reserve_size, | |
119 "alignment increased end addr"); | |
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120 assert((res & (prefix_align - 1)) == 0, "bad alignment of prefix"); |
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121 assert(((res + prefix_size) & (suffix_align - 1)) == 0, |
0 | 122 "bad alignment of suffix"); |
123 } | |
124 #endif | |
125 | |
126 return result; | |
127 } | |
128 | |
1618 | 129 // Helper method. |
130 static bool failed_to_reserve_as_requested(char* base, char* requested_address, | |
131 const size_t size, bool special) | |
132 { | |
133 if (base == requested_address || requested_address == NULL) | |
134 return false; // did not fail | |
135 | |
136 if (base != NULL) { | |
137 // Different reserve address may be acceptable in other cases | |
138 // but for compressed oops heap should be at requested address. | |
139 assert(UseCompressedOops, "currently requested address used only for compressed oops"); | |
140 if (PrintCompressedOopsMode) { | |
141 tty->cr(); | |
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142 tty->print_cr("Reserved memory not at requested address: " PTR_FORMAT " vs " PTR_FORMAT, base, requested_address); |
1618 | 143 } |
144 // OS ignored requested address. Try different address. | |
145 if (special) { | |
146 if (!os::release_memory_special(base, size)) { | |
147 fatal("os::release_memory_special failed"); | |
148 } | |
149 } else { | |
150 if (!os::release_memory(base, size)) { | |
151 fatal("os::release_memory failed"); | |
152 } | |
153 } | |
154 } | |
155 return true; | |
156 } | |
157 | |
0 | 158 ReservedSpace::ReservedSpace(const size_t prefix_size, |
159 const size_t prefix_align, | |
160 const size_t suffix_size, | |
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161 const size_t suffix_align, |
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162 char* requested_address, |
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163 const size_t noaccess_prefix) |
0 | 164 { |
165 assert(prefix_size != 0, "sanity"); | |
166 assert(prefix_align != 0, "sanity"); | |
167 assert(suffix_size != 0, "sanity"); | |
168 assert(suffix_align != 0, "sanity"); | |
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169 assert((prefix_size & (prefix_align - 1)) == 0, |
0 | 170 "prefix_size not divisible by prefix_align"); |
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171 assert((suffix_size & (suffix_align - 1)) == 0, |
0 | 172 "suffix_size not divisible by suffix_align"); |
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173 assert((suffix_align & (prefix_align - 1)) == 0, |
0 | 174 "suffix_align not divisible by prefix_align"); |
175 | |
1618 | 176 // Assert that if noaccess_prefix is used, it is the same as prefix_align. |
177 assert(noaccess_prefix == 0 || | |
178 noaccess_prefix == prefix_align, "noaccess prefix wrong"); | |
179 | |
237
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180 // Add in noaccess_prefix to prefix_size; |
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181 const size_t adjusted_prefix_size = prefix_size + noaccess_prefix; |
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182 const size_t size = adjusted_prefix_size + suffix_size; |
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183 |
0 | 184 // On systems where the entire region has to be reserved and committed up |
185 // front, the compound alignment normally done by this method is unnecessary. | |
186 const bool try_reserve_special = UseLargePages && | |
187 prefix_align == os::large_page_size(); | |
188 if (!os::can_commit_large_page_memory() && try_reserve_special) { | |
656 | 189 initialize(size, prefix_align, true, requested_address, noaccess_prefix, |
190 false); | |
0 | 191 return; |
192 } | |
193 | |
194 _base = NULL; | |
195 _size = 0; | |
196 _alignment = 0; | |
197 _special = false; | |
237
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198 _noaccess_prefix = 0; |
656 | 199 _executable = false; |
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200 |
0 | 201 // Optimistically try to reserve the exact size needed. |
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202 char* addr; |
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203 if (requested_address != 0) { |
1618 | 204 requested_address -= noaccess_prefix; // adjust address |
205 assert(requested_address != NULL, "huge noaccess prefix?"); | |
206 addr = os::attempt_reserve_memory_at(size, requested_address); | |
207 if (failed_to_reserve_as_requested(addr, requested_address, size, false)) { | |
208 // OS ignored requested address. Try different address. | |
209 addr = NULL; | |
210 } | |
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211 } else { |
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212 addr = os::reserve_memory(size, NULL, prefix_align); |
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213 } |
0 | 214 if (addr == NULL) return; |
215 | |
216 // Check whether the result has the needed alignment (unlikely unless | |
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217 // prefix_align < suffix_align). |
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218 const size_t ofs = (size_t(addr) + adjusted_prefix_size) & (suffix_align - 1); |
0 | 219 if (ofs != 0) { |
220 // Wrong alignment. Release, allocate more space and do manual alignment. | |
221 // | |
222 // On most operating systems, another allocation with a somewhat larger size | |
223 // will return an address "close to" that of the previous allocation. The | |
224 // result is often the same address (if the kernel hands out virtual | |
225 // addresses from low to high), or an address that is offset by the increase | |
226 // in size. Exploit that to minimize the amount of extra space requested. | |
227 if (!os::release_memory(addr, size)) { | |
228 fatal("os::release_memory failed"); | |
229 } | |
230 | |
231 const size_t extra = MAX2(ofs, suffix_align - ofs); | |
237
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232 addr = reserve_and_align(size + extra, adjusted_prefix_size, prefix_align, |
0 | 233 suffix_size, suffix_align); |
234 if (addr == NULL) { | |
235 // Try an even larger region. If this fails, address space is exhausted. | |
237
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236 addr = reserve_and_align(size + suffix_align, adjusted_prefix_size, |
0 | 237 prefix_align, suffix_size, suffix_align); |
238 } | |
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239 |
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240 if (requested_address != 0 && |
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241 failed_to_reserve_as_requested(addr, requested_address, size, false)) { |
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242 // As a result of the alignment constraints, the allocated addr differs |
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243 // from the requested address. Return back to the caller who can |
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244 // take remedial action (like try again without a requested address). |
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245 assert(_base == NULL, "should be"); |
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246 return; |
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247 } |
0 | 248 } |
249 | |
250 _base = addr; | |
251 _size = size; | |
252 _alignment = prefix_align; | |
237
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253 _noaccess_prefix = noaccess_prefix; |
0 | 254 } |
255 | |
256 void ReservedSpace::initialize(size_t size, size_t alignment, bool large, | |
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257 char* requested_address, |
656 | 258 const size_t noaccess_prefix, |
259 bool executable) { | |
0 | 260 const size_t granularity = os::vm_allocation_granularity(); |
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261 assert((size & (granularity - 1)) == 0, |
0 | 262 "size not aligned to os::vm_allocation_granularity()"); |
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263 assert((alignment & (granularity - 1)) == 0, |
0 | 264 "alignment not aligned to os::vm_allocation_granularity()"); |
265 assert(alignment == 0 || is_power_of_2((intptr_t)alignment), | |
266 "not a power of 2"); | |
267 | |
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268 alignment = MAX2(alignment, (size_t)os::vm_page_size()); |
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269 |
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270 // Assert that if noaccess_prefix is used, it is the same as alignment. |
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271 assert(noaccess_prefix == 0 || |
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272 noaccess_prefix == alignment, "noaccess prefix wrong"); |
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273 |
0 | 274 _base = NULL; |
275 _size = 0; | |
276 _special = false; | |
656 | 277 _executable = executable; |
0 | 278 _alignment = 0; |
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279 _noaccess_prefix = 0; |
0 | 280 if (size == 0) { |
281 return; | |
282 } | |
283 | |
284 // If OS doesn't support demand paging for large page memory, we need | |
285 // to use reserve_memory_special() to reserve and pin the entire region. | |
286 bool special = large && !os::can_commit_large_page_memory(); | |
287 char* base = NULL; | |
288 | |
1618 | 289 if (requested_address != 0) { |
290 requested_address -= noaccess_prefix; // adjust requested address | |
291 assert(requested_address != NULL, "huge noaccess prefix?"); | |
292 } | |
293 | |
0 | 294 if (special) { |
295 | |
656 | 296 base = os::reserve_memory_special(size, requested_address, executable); |
0 | 297 |
298 if (base != NULL) { | |
1618 | 299 if (failed_to_reserve_as_requested(base, requested_address, size, true)) { |
300 // OS ignored requested address. Try different address. | |
301 return; | |
302 } | |
0 | 303 // Check alignment constraints |
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304 assert((uintptr_t) base % alignment == 0, |
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305 "Large pages returned a non-aligned address"); |
0 | 306 _special = true; |
307 } else { | |
308 // failed; try to reserve regular memory below | |
1618 | 309 if (UseLargePages && (!FLAG_IS_DEFAULT(UseLargePages) || |
310 !FLAG_IS_DEFAULT(LargePageSizeInBytes))) { | |
311 if (PrintCompressedOopsMode) { | |
312 tty->cr(); | |
313 tty->print_cr("Reserve regular memory without large pages."); | |
314 } | |
315 } | |
0 | 316 } |
317 } | |
318 | |
319 if (base == NULL) { | |
320 // Optimistically assume that the OSes returns an aligned base pointer. | |
321 // When reserving a large address range, most OSes seem to align to at | |
322 // least 64K. | |
323 | |
324 // If the memory was requested at a particular address, use | |
325 // os::attempt_reserve_memory_at() to avoid over mapping something | |
326 // important. If available space is not detected, return NULL. | |
327 | |
328 if (requested_address != 0) { | |
1618 | 329 base = os::attempt_reserve_memory_at(size, requested_address); |
330 if (failed_to_reserve_as_requested(base, requested_address, size, false)) { | |
331 // OS ignored requested address. Try different address. | |
332 base = NULL; | |
333 } | |
0 | 334 } else { |
335 base = os::reserve_memory(size, NULL, alignment); | |
336 } | |
337 | |
338 if (base == NULL) return; | |
339 | |
340 // Check alignment constraints | |
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341 if ((((size_t)base + noaccess_prefix) & (alignment - 1)) != 0) { |
0 | 342 // Base not aligned, retry |
343 if (!os::release_memory(base, size)) fatal("os::release_memory failed"); | |
344 // Reserve size large enough to do manual alignment and | |
345 // increase size to a multiple of the desired alignment | |
346 size = align_size_up(size, alignment); | |
347 size_t extra_size = size + alignment; | |
342 | 348 do { |
349 char* extra_base = os::reserve_memory(extra_size, NULL, alignment); | |
350 if (extra_base == NULL) return; | |
351 // Do manual alignement | |
352 base = (char*) align_size_up((uintptr_t) extra_base, alignment); | |
353 assert(base >= extra_base, "just checking"); | |
354 // Re-reserve the region at the aligned base address. | |
355 os::release_memory(extra_base, extra_size); | |
356 base = os::reserve_memory(size, base); | |
357 } while (base == NULL); | |
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358 |
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359 if (requested_address != 0 && |
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360 failed_to_reserve_as_requested(base, requested_address, size, false)) { |
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361 // As a result of the alignment constraints, the allocated base differs |
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362 // from the requested address. Return back to the caller who can |
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363 // take remedial action (like try again without a requested address). |
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364 assert(_base == NULL, "should be"); |
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365 return; |
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366 } |
0 | 367 } |
368 } | |
369 // Done | |
370 _base = base; | |
371 _size = size; | |
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372 _alignment = alignment; |
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373 _noaccess_prefix = noaccess_prefix; |
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374 |
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375 // Assert that if noaccess_prefix is used, it is the same as alignment. |
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376 assert(noaccess_prefix == 0 || |
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377 noaccess_prefix == _alignment, "noaccess prefix wrong"); |
0 | 378 |
379 assert(markOopDesc::encode_pointer_as_mark(_base)->decode_pointer() == _base, | |
380 "area must be distinguisable from marks for mark-sweep"); | |
381 assert(markOopDesc::encode_pointer_as_mark(&_base[size])->decode_pointer() == &_base[size], | |
382 "area must be distinguisable from marks for mark-sweep"); | |
383 } | |
384 | |
385 | |
386 ReservedSpace::ReservedSpace(char* base, size_t size, size_t alignment, | |
656 | 387 bool special, bool executable) { |
0 | 388 assert((size % os::vm_allocation_granularity()) == 0, |
389 "size not allocation aligned"); | |
390 _base = base; | |
391 _size = size; | |
392 _alignment = alignment; | |
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393 _noaccess_prefix = 0; |
0 | 394 _special = special; |
656 | 395 _executable = executable; |
0 | 396 } |
397 | |
398 | |
399 ReservedSpace ReservedSpace::first_part(size_t partition_size, size_t alignment, | |
400 bool split, bool realloc) { | |
401 assert(partition_size <= size(), "partition failed"); | |
402 if (split) { | |
656 | 403 os::split_reserved_memory(base(), size(), partition_size, realloc); |
0 | 404 } |
656 | 405 ReservedSpace result(base(), partition_size, alignment, special(), |
406 executable()); | |
0 | 407 return result; |
408 } | |
409 | |
410 | |
411 ReservedSpace | |
412 ReservedSpace::last_part(size_t partition_size, size_t alignment) { | |
413 assert(partition_size <= size(), "partition failed"); | |
414 ReservedSpace result(base() + partition_size, size() - partition_size, | |
656 | 415 alignment, special(), executable()); |
0 | 416 return result; |
417 } | |
418 | |
419 | |
420 size_t ReservedSpace::page_align_size_up(size_t size) { | |
421 return align_size_up(size, os::vm_page_size()); | |
422 } | |
423 | |
424 | |
425 size_t ReservedSpace::page_align_size_down(size_t size) { | |
426 return align_size_down(size, os::vm_page_size()); | |
427 } | |
428 | |
429 | |
430 size_t ReservedSpace::allocation_align_size_up(size_t size) { | |
431 return align_size_up(size, os::vm_allocation_granularity()); | |
432 } | |
433 | |
434 | |
435 size_t ReservedSpace::allocation_align_size_down(size_t size) { | |
436 return align_size_down(size, os::vm_allocation_granularity()); | |
437 } | |
438 | |
439 | |
440 void ReservedSpace::release() { | |
441 if (is_reserved()) { | |
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442 char *real_base = _base - _noaccess_prefix; |
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443 const size_t real_size = _size + _noaccess_prefix; |
0 | 444 if (special()) { |
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445 os::release_memory_special(real_base, real_size); |
0 | 446 } else{ |
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447 os::release_memory(real_base, real_size); |
0 | 448 } |
449 _base = NULL; | |
450 _size = 0; | |
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451 _noaccess_prefix = 0; |
0 | 452 _special = false; |
656 | 453 _executable = false; |
0 | 454 } |
455 } | |
456 | |
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457 void ReservedSpace::protect_noaccess_prefix(const size_t size) { |
1618 | 458 assert( (_noaccess_prefix != 0) == (UseCompressedOops && _base != NULL && |
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459 (Universe::narrow_oop_base() != NULL) && |
1618 | 460 Universe::narrow_oop_use_implicit_null_checks()), |
461 "noaccess_prefix should be used only with non zero based compressed oops"); | |
462 | |
463 // If there is no noaccess prefix, return. | |
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464 if (_noaccess_prefix == 0) return; |
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465 |
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466 assert(_noaccess_prefix >= (size_t)os::vm_page_size(), |
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467 "must be at least page size big"); |
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468 |
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469 // Protect memory at the base of the allocated region. |
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470 // If special, the page was committed (only matters on windows) |
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471 if (!os::protect_memory(_base, _noaccess_prefix, os::MEM_PROT_NONE, |
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472 _special)) { |
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473 fatal("cannot protect protection page"); |
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474 } |
1618 | 475 if (PrintCompressedOopsMode) { |
476 tty->cr(); | |
477 tty->print_cr("Protected page at the reserved heap base: " PTR_FORMAT " / " INTX_FORMAT " bytes", _base, _noaccess_prefix); | |
478 } | |
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479 |
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480 _base += _noaccess_prefix; |
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481 _size -= _noaccess_prefix; |
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482 assert((size == _size) && ((uintptr_t)_base % _alignment == 0), |
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483 "must be exactly of required size and alignment"); |
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484 } |
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485 |
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486 ReservedHeapSpace::ReservedHeapSpace(size_t size, size_t alignment, |
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487 bool large, char* requested_address) : |
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488 ReservedSpace(size, alignment, large, |
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489 requested_address, |
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490 (UseCompressedOops && (Universe::narrow_oop_base() != NULL) && |
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491 Universe::narrow_oop_use_implicit_null_checks()) ? |
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492 lcm(os::vm_page_size(), alignment) : 0) { |
6197 | 493 if (base() > 0) { |
494 MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap); | |
495 } | |
496 | |
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497 // Only reserved space for the java heap should have a noaccess_prefix |
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498 // if using compressed oops. |
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499 protect_noaccess_prefix(size); |
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500 } |
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501 |
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502 ReservedHeapSpace::ReservedHeapSpace(const size_t prefix_size, |
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503 const size_t prefix_align, |
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504 const size_t suffix_size, |
642
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505 const size_t suffix_align, |
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506 char* requested_address) : |
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507 ReservedSpace(prefix_size, prefix_align, suffix_size, suffix_align, |
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508 requested_address, |
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509 (UseCompressedOops && (Universe::narrow_oop_base() != NULL) && |
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510 Universe::narrow_oop_use_implicit_null_checks()) ? |
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511 lcm(os::vm_page_size(), prefix_align) : 0) { |
6197 | 512 if (base() > 0) { |
513 MemTracker::record_virtual_memory_type((address)base(), mtJavaHeap); | |
514 } | |
515 | |
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516 protect_noaccess_prefix(prefix_size+suffix_size); |
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517 } |
0 | 518 |
656 | 519 // Reserve space for code segment. Same as Java heap only we mark this as |
520 // executable. | |
521 ReservedCodeSpace::ReservedCodeSpace(size_t r_size, | |
522 size_t rs_align, | |
523 bool large) : | |
524 ReservedSpace(r_size, rs_align, large, /*executable*/ true) { | |
6197 | 525 MemTracker::record_virtual_memory_type((address)base(), mtCode); |
656 | 526 } |
527 | |
0 | 528 // VirtualSpace |
529 | |
530 VirtualSpace::VirtualSpace() { | |
531 _low_boundary = NULL; | |
532 _high_boundary = NULL; | |
533 _low = NULL; | |
534 _high = NULL; | |
535 _lower_high = NULL; | |
536 _middle_high = NULL; | |
537 _upper_high = NULL; | |
538 _lower_high_boundary = NULL; | |
539 _middle_high_boundary = NULL; | |
540 _upper_high_boundary = NULL; | |
541 _lower_alignment = 0; | |
542 _middle_alignment = 0; | |
543 _upper_alignment = 0; | |
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544 _special = false; |
656 | 545 _executable = false; |
0 | 546 } |
547 | |
548 | |
549 bool VirtualSpace::initialize(ReservedSpace rs, size_t committed_size) { | |
550 if(!rs.is_reserved()) return false; // allocation failed. | |
551 assert(_low_boundary == NULL, "VirtualSpace already initialized"); | |
552 _low_boundary = rs.base(); | |
553 _high_boundary = low_boundary() + rs.size(); | |
554 | |
555 _low = low_boundary(); | |
556 _high = low(); | |
557 | |
558 _special = rs.special(); | |
656 | 559 _executable = rs.executable(); |
0 | 560 |
561 // When a VirtualSpace begins life at a large size, make all future expansion | |
562 // and shrinking occur aligned to a granularity of large pages. This avoids | |
563 // fragmentation of physical addresses that inhibits the use of large pages | |
564 // by the OS virtual memory system. Empirically, we see that with a 4MB | |
565 // page size, the only spaces that get handled this way are codecache and | |
566 // the heap itself, both of which provide a substantial performance | |
567 // boost in many benchmarks when covered by large pages. | |
568 // | |
569 // No attempt is made to force large page alignment at the very top and | |
570 // bottom of the space if they are not aligned so already. | |
571 _lower_alignment = os::vm_page_size(); | |
572 _middle_alignment = os::page_size_for_region(rs.size(), rs.size(), 1); | |
573 _upper_alignment = os::vm_page_size(); | |
574 | |
575 // End of each region | |
576 _lower_high_boundary = (char*) round_to((intptr_t) low_boundary(), middle_alignment()); | |
577 _middle_high_boundary = (char*) round_down((intptr_t) high_boundary(), middle_alignment()); | |
578 _upper_high_boundary = high_boundary(); | |
579 | |
580 // High address of each region | |
581 _lower_high = low_boundary(); | |
582 _middle_high = lower_high_boundary(); | |
583 _upper_high = middle_high_boundary(); | |
584 | |
585 // commit to initial size | |
586 if (committed_size > 0) { | |
587 if (!expand_by(committed_size)) { | |
588 return false; | |
589 } | |
590 } | |
591 return true; | |
592 } | |
593 | |
594 | |
595 VirtualSpace::~VirtualSpace() { | |
596 release(); | |
597 } | |
598 | |
599 | |
600 void VirtualSpace::release() { | |
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601 // This does not release memory it never reserved. |
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602 // Caller must release via rs.release(); |
0 | 603 _low_boundary = NULL; |
604 _high_boundary = NULL; | |
605 _low = NULL; | |
606 _high = NULL; | |
607 _lower_high = NULL; | |
608 _middle_high = NULL; | |
609 _upper_high = NULL; | |
610 _lower_high_boundary = NULL; | |
611 _middle_high_boundary = NULL; | |
612 _upper_high_boundary = NULL; | |
613 _lower_alignment = 0; | |
614 _middle_alignment = 0; | |
615 _upper_alignment = 0; | |
616 _special = false; | |
656 | 617 _executable = false; |
0 | 618 } |
619 | |
620 | |
621 size_t VirtualSpace::committed_size() const { | |
622 return pointer_delta(high(), low(), sizeof(char)); | |
623 } | |
624 | |
625 | |
626 size_t VirtualSpace::reserved_size() const { | |
627 return pointer_delta(high_boundary(), low_boundary(), sizeof(char)); | |
628 } | |
629 | |
630 | |
631 size_t VirtualSpace::uncommitted_size() const { | |
632 return reserved_size() - committed_size(); | |
633 } | |
634 | |
635 | |
636 bool VirtualSpace::contains(const void* p) const { | |
637 return low() <= (const char*) p && (const char*) p < high(); | |
638 } | |
639 | |
640 /* | |
641 First we need to determine if a particular virtual space is using large | |
642 pages. This is done at the initialize function and only virtual spaces | |
643 that are larger than LargePageSizeInBytes use large pages. Once we | |
644 have determined this, all expand_by and shrink_by calls must grow and | |
645 shrink by large page size chunks. If a particular request | |
646 is within the current large page, the call to commit and uncommit memory | |
647 can be ignored. In the case that the low and high boundaries of this | |
648 space is not large page aligned, the pages leading to the first large | |
649 page address and the pages after the last large page address must be | |
650 allocated with default pages. | |
651 */ | |
652 bool VirtualSpace::expand_by(size_t bytes, bool pre_touch) { | |
653 if (uncommitted_size() < bytes) return false; | |
654 | |
655 if (special()) { | |
656 // don't commit memory if the entire space is pinned in memory | |
657 _high += bytes; | |
658 return true; | |
659 } | |
660 | |
661 char* previous_high = high(); | |
662 char* unaligned_new_high = high() + bytes; | |
663 assert(unaligned_new_high <= high_boundary(), | |
664 "cannot expand by more than upper boundary"); | |
665 | |
666 // Calculate where the new high for each of the regions should be. If | |
667 // the low_boundary() and high_boundary() are LargePageSizeInBytes aligned | |
668 // then the unaligned lower and upper new highs would be the | |
669 // lower_high() and upper_high() respectively. | |
670 char* unaligned_lower_new_high = | |
671 MIN2(unaligned_new_high, lower_high_boundary()); | |
672 char* unaligned_middle_new_high = | |
673 MIN2(unaligned_new_high, middle_high_boundary()); | |
674 char* unaligned_upper_new_high = | |
675 MIN2(unaligned_new_high, upper_high_boundary()); | |
676 | |
677 // Align the new highs based on the regions alignment. lower and upper | |
678 // alignment will always be default page size. middle alignment will be | |
679 // LargePageSizeInBytes if the actual size of the virtual space is in | |
680 // fact larger than LargePageSizeInBytes. | |
681 char* aligned_lower_new_high = | |
682 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment()); | |
683 char* aligned_middle_new_high = | |
684 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment()); | |
685 char* aligned_upper_new_high = | |
686 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment()); | |
687 | |
688 // Determine which regions need to grow in this expand_by call. | |
689 // If you are growing in the lower region, high() must be in that | |
690 // region so calcuate the size based on high(). For the middle and | |
691 // upper regions, determine the starting point of growth based on the | |
692 // location of high(). By getting the MAX of the region's low address | |
693 // (or the prevoius region's high address) and high(), we can tell if it | |
694 // is an intra or inter region growth. | |
695 size_t lower_needs = 0; | |
696 if (aligned_lower_new_high > lower_high()) { | |
697 lower_needs = | |
698 pointer_delta(aligned_lower_new_high, lower_high(), sizeof(char)); | |
699 } | |
700 size_t middle_needs = 0; | |
701 if (aligned_middle_new_high > middle_high()) { | |
702 middle_needs = | |
703 pointer_delta(aligned_middle_new_high, middle_high(), sizeof(char)); | |
704 } | |
705 size_t upper_needs = 0; | |
706 if (aligned_upper_new_high > upper_high()) { | |
707 upper_needs = | |
708 pointer_delta(aligned_upper_new_high, upper_high(), sizeof(char)); | |
709 } | |
710 | |
711 // Check contiguity. | |
712 assert(low_boundary() <= lower_high() && | |
713 lower_high() <= lower_high_boundary(), | |
714 "high address must be contained within the region"); | |
715 assert(lower_high_boundary() <= middle_high() && | |
716 middle_high() <= middle_high_boundary(), | |
717 "high address must be contained within the region"); | |
718 assert(middle_high_boundary() <= upper_high() && | |
719 upper_high() <= upper_high_boundary(), | |
720 "high address must be contained within the region"); | |
721 | |
722 // Commit regions | |
723 if (lower_needs > 0) { | |
724 assert(low_boundary() <= lower_high() && | |
725 lower_high() + lower_needs <= lower_high_boundary(), | |
726 "must not expand beyond region"); | |
656 | 727 if (!os::commit_memory(lower_high(), lower_needs, _executable)) { |
0 | 728 debug_only(warning("os::commit_memory failed")); |
729 return false; | |
730 } else { | |
731 _lower_high += lower_needs; | |
732 } | |
733 } | |
734 if (middle_needs > 0) { | |
735 assert(lower_high_boundary() <= middle_high() && | |
736 middle_high() + middle_needs <= middle_high_boundary(), | |
737 "must not expand beyond region"); | |
656 | 738 if (!os::commit_memory(middle_high(), middle_needs, middle_alignment(), |
739 _executable)) { | |
0 | 740 debug_only(warning("os::commit_memory failed")); |
741 return false; | |
742 } | |
743 _middle_high += middle_needs; | |
744 } | |
745 if (upper_needs > 0) { | |
746 assert(middle_high_boundary() <= upper_high() && | |
747 upper_high() + upper_needs <= upper_high_boundary(), | |
748 "must not expand beyond region"); | |
656 | 749 if (!os::commit_memory(upper_high(), upper_needs, _executable)) { |
0 | 750 debug_only(warning("os::commit_memory failed")); |
751 return false; | |
752 } else { | |
753 _upper_high += upper_needs; | |
754 } | |
755 } | |
756 | |
757 if (pre_touch || AlwaysPreTouch) { | |
758 int vm_ps = os::vm_page_size(); | |
759 for (char* curr = previous_high; | |
760 curr < unaligned_new_high; | |
761 curr += vm_ps) { | |
762 // Note the use of a write here; originally we tried just a read, but | |
763 // since the value read was unused, the optimizer removed the read. | |
764 // If we ever have a concurrent touchahead thread, we'll want to use | |
765 // a read, to avoid the potential of overwriting data (if a mutator | |
766 // thread beats the touchahead thread to a page). There are various | |
767 // ways of making sure this read is not optimized away: for example, | |
768 // generating the code for a read procedure at runtime. | |
769 *curr = 0; | |
770 } | |
771 } | |
772 | |
773 _high += bytes; | |
774 return true; | |
775 } | |
776 | |
777 // A page is uncommitted if the contents of the entire page is deemed unusable. | |
778 // Continue to decrement the high() pointer until it reaches a page boundary | |
779 // in which case that particular page can now be uncommitted. | |
780 void VirtualSpace::shrink_by(size_t size) { | |
781 if (committed_size() < size) | |
782 fatal("Cannot shrink virtual space to negative size"); | |
783 | |
784 if (special()) { | |
785 // don't uncommit if the entire space is pinned in memory | |
786 _high -= size; | |
787 return; | |
788 } | |
789 | |
790 char* unaligned_new_high = high() - size; | |
791 assert(unaligned_new_high >= low_boundary(), "cannot shrink past lower boundary"); | |
792 | |
793 // Calculate new unaligned address | |
794 char* unaligned_upper_new_high = | |
795 MAX2(unaligned_new_high, middle_high_boundary()); | |
796 char* unaligned_middle_new_high = | |
797 MAX2(unaligned_new_high, lower_high_boundary()); | |
798 char* unaligned_lower_new_high = | |
799 MAX2(unaligned_new_high, low_boundary()); | |
800 | |
801 // Align address to region's alignment | |
802 char* aligned_upper_new_high = | |
803 (char*) round_to((intptr_t) unaligned_upper_new_high, upper_alignment()); | |
804 char* aligned_middle_new_high = | |
805 (char*) round_to((intptr_t) unaligned_middle_new_high, middle_alignment()); | |
806 char* aligned_lower_new_high = | |
807 (char*) round_to((intptr_t) unaligned_lower_new_high, lower_alignment()); | |
808 | |
809 // Determine which regions need to shrink | |
810 size_t upper_needs = 0; | |
811 if (aligned_upper_new_high < upper_high()) { | |
812 upper_needs = | |
813 pointer_delta(upper_high(), aligned_upper_new_high, sizeof(char)); | |
814 } | |
815 size_t middle_needs = 0; | |
816 if (aligned_middle_new_high < middle_high()) { | |
817 middle_needs = | |
818 pointer_delta(middle_high(), aligned_middle_new_high, sizeof(char)); | |
819 } | |
820 size_t lower_needs = 0; | |
821 if (aligned_lower_new_high < lower_high()) { | |
822 lower_needs = | |
823 pointer_delta(lower_high(), aligned_lower_new_high, sizeof(char)); | |
824 } | |
825 | |
826 // Check contiguity. | |
827 assert(middle_high_boundary() <= upper_high() && | |
828 upper_high() <= upper_high_boundary(), | |
829 "high address must be contained within the region"); | |
830 assert(lower_high_boundary() <= middle_high() && | |
831 middle_high() <= middle_high_boundary(), | |
832 "high address must be contained within the region"); | |
833 assert(low_boundary() <= lower_high() && | |
834 lower_high() <= lower_high_boundary(), | |
835 "high address must be contained within the region"); | |
836 | |
837 // Uncommit | |
838 if (upper_needs > 0) { | |
839 assert(middle_high_boundary() <= aligned_upper_new_high && | |
840 aligned_upper_new_high + upper_needs <= upper_high_boundary(), | |
841 "must not shrink beyond region"); | |
842 if (!os::uncommit_memory(aligned_upper_new_high, upper_needs)) { | |
843 debug_only(warning("os::uncommit_memory failed")); | |
844 return; | |
845 } else { | |
846 _upper_high -= upper_needs; | |
847 } | |
848 } | |
849 if (middle_needs > 0) { | |
850 assert(lower_high_boundary() <= aligned_middle_new_high && | |
851 aligned_middle_new_high + middle_needs <= middle_high_boundary(), | |
852 "must not shrink beyond region"); | |
853 if (!os::uncommit_memory(aligned_middle_new_high, middle_needs)) { | |
854 debug_only(warning("os::uncommit_memory failed")); | |
855 return; | |
856 } else { | |
857 _middle_high -= middle_needs; | |
858 } | |
859 } | |
860 if (lower_needs > 0) { | |
861 assert(low_boundary() <= aligned_lower_new_high && | |
862 aligned_lower_new_high + lower_needs <= lower_high_boundary(), | |
863 "must not shrink beyond region"); | |
864 if (!os::uncommit_memory(aligned_lower_new_high, lower_needs)) { | |
865 debug_only(warning("os::uncommit_memory failed")); | |
866 return; | |
867 } else { | |
868 _lower_high -= lower_needs; | |
869 } | |
870 } | |
871 | |
872 _high -= size; | |
873 } | |
874 | |
875 #ifndef PRODUCT | |
876 void VirtualSpace::check_for_contiguity() { | |
877 // Check contiguity. | |
878 assert(low_boundary() <= lower_high() && | |
879 lower_high() <= lower_high_boundary(), | |
880 "high address must be contained within the region"); | |
881 assert(lower_high_boundary() <= middle_high() && | |
882 middle_high() <= middle_high_boundary(), | |
883 "high address must be contained within the region"); | |
884 assert(middle_high_boundary() <= upper_high() && | |
885 upper_high() <= upper_high_boundary(), | |
886 "high address must be contained within the region"); | |
887 assert(low() >= low_boundary(), "low"); | |
888 assert(low_boundary() <= lower_high_boundary(), "lower high boundary"); | |
889 assert(upper_high_boundary() <= high_boundary(), "upper high boundary"); | |
890 assert(high() <= upper_high(), "upper high"); | |
891 } | |
892 | |
893 void VirtualSpace::print() { | |
894 tty->print ("Virtual space:"); | |
895 if (special()) tty->print(" (pinned in memory)"); | |
896 tty->cr(); | |
897 tty->print_cr(" - committed: %ld", committed_size()); | |
898 tty->print_cr(" - reserved: %ld", reserved_size()); | |
899 tty->print_cr(" - [low, high]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low(), high()); | |
900 tty->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]", low_boundary(), high_boundary()); | |
901 } | |
902 | |
903 #endif |