Mercurial > hg > graal-compiler
annotate src/share/vm/gc_implementation/parallelScavenge/psVirtualspace.cpp @ 237:1fdb98a17101
6716785: implicit null checks not triggering with CompressedOops
Summary: allocate alignment-sized page(s) below java heap so that memory accesses at heap_base+1page give signal and cause an implicit null check
Reviewed-by: kvn, jmasa, phh, jcoomes
| author | coleenp |
|---|---|
| date | Sat, 19 Jul 2008 17:38:22 -0400 |
| parents | a61af66fc99e |
| children | 9ee9cf798b59 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 * Copyright 2003-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 #include "incls/_precompiled.incl" | |
| 26 #include "incls/_psVirtualspace.cpp.incl" | |
| 27 | |
| 28 // PSVirtualSpace | |
| 29 | |
| 30 PSVirtualSpace::PSVirtualSpace(ReservedSpace rs, size_t alignment) : | |
| 31 _alignment(alignment) | |
| 32 { | |
| 33 set_reserved(rs); | |
| 34 set_committed(reserved_low_addr(), reserved_low_addr()); | |
| 35 DEBUG_ONLY(verify()); | |
| 36 } | |
| 37 | |
| 38 PSVirtualSpace::PSVirtualSpace(ReservedSpace rs) : | |
| 39 _alignment(os::vm_page_size()) | |
| 40 { | |
| 41 set_reserved(rs); | |
| 42 set_committed(reserved_low_addr(), reserved_low_addr()); | |
| 43 DEBUG_ONLY(verify()); | |
| 44 } | |
| 45 | |
| 46 // Deprecated. | |
| 47 PSVirtualSpace::PSVirtualSpace(): _alignment(os::vm_page_size()) { | |
| 48 } | |
| 49 | |
| 50 // Deprecated. | |
| 51 bool PSVirtualSpace::initialize(ReservedSpace rs, | |
| 52 size_t commit_size) { | |
| 53 set_reserved(rs); | |
| 54 set_committed(reserved_low_addr(), reserved_low_addr()); | |
| 55 | |
| 56 // Commit to initial size. | |
| 57 assert(commit_size <= rs.size(), "commit_size too big"); | |
| 58 bool result = commit_size > 0 ? expand_by(commit_size) : true; | |
| 59 DEBUG_ONLY(verify()); | |
| 60 return result; | |
| 61 } | |
| 62 | |
| 63 PSVirtualSpace::~PSVirtualSpace() { | |
| 64 release(); | |
| 65 } | |
| 66 | |
| 67 bool PSVirtualSpace::contains(void* p) const { | |
| 68 char* const cp = (char*)p; | |
| 69 return cp >= committed_low_addr() && cp < committed_high_addr(); | |
| 70 } | |
| 71 | |
| 72 void PSVirtualSpace::release() { | |
| 73 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
|
237
1fdb98a17101
6716785: implicit null checks not triggering with CompressedOops
coleenp
parents:
0
diff
changeset
|
74 // This may not release memory it didn't reserve. |
|
1fdb98a17101
6716785: implicit null checks not triggering with CompressedOops
coleenp
parents:
0
diff
changeset
|
75 // Use rs.release() to release the underlying memory instead. |
| 0 | 76 _reserved_low_addr = _reserved_high_addr = NULL; |
| 77 _committed_low_addr = _committed_high_addr = NULL; | |
| 78 _special = false; | |
| 79 } | |
| 80 | |
| 81 bool PSVirtualSpace::expand_by(size_t bytes, bool pre_touch) { | |
| 82 assert(is_aligned(bytes), "arg not aligned"); | |
| 83 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 84 | |
| 85 if (uncommitted_size() < bytes) { | |
| 86 return false; | |
| 87 } | |
| 88 | |
| 89 char* const base_addr = committed_high_addr(); | |
| 90 bool result = special() || os::commit_memory(base_addr, bytes, alignment()); | |
| 91 if (result) { | |
| 92 _committed_high_addr += bytes; | |
| 93 } | |
| 94 | |
| 95 if (pre_touch || AlwaysPreTouch) { | |
| 96 for (char* curr = base_addr; | |
| 97 curr < _committed_high_addr; | |
| 98 curr += os::vm_page_size()) { | |
| 99 char tmp = *curr; | |
| 100 *curr = 0; | |
| 101 } | |
| 102 } | |
| 103 | |
| 104 return result; | |
| 105 } | |
| 106 | |
| 107 bool PSVirtualSpace::shrink_by(size_t bytes) { | |
| 108 assert(is_aligned(bytes), "arg not aligned"); | |
| 109 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 110 | |
| 111 if (committed_size() < bytes) { | |
| 112 return false; | |
| 113 } | |
| 114 | |
| 115 char* const base_addr = committed_high_addr() - bytes; | |
| 116 bool result = special() || os::uncommit_memory(base_addr, bytes); | |
| 117 if (result) { | |
| 118 _committed_high_addr -= bytes; | |
| 119 } | |
| 120 | |
| 121 return result; | |
| 122 } | |
| 123 | |
| 124 size_t | |
| 125 PSVirtualSpace::expand_into(PSVirtualSpace* other_space, size_t bytes) { | |
| 126 assert(is_aligned(bytes), "arg not aligned"); | |
| 127 assert(grows_up(), "this space must grow up"); | |
| 128 assert(other_space->grows_down(), "other space must grow down"); | |
| 129 assert(reserved_high_addr() == other_space->reserved_low_addr(), | |
| 130 "spaces not contiguous"); | |
| 131 assert(special() == other_space->special(), "one space is special, the other is not"); | |
| 132 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 133 DEBUG_ONLY(PSVirtualSpaceVerifier other_verifier(other_space)); | |
| 134 | |
| 135 size_t bytes_needed = bytes; | |
| 136 | |
| 137 // First use the uncommitted region in this space. | |
| 138 size_t tmp_bytes = MIN2(uncommitted_size(), bytes_needed); | |
| 139 if (tmp_bytes > 0) { | |
| 140 if (expand_by(tmp_bytes)) { | |
| 141 bytes_needed -= tmp_bytes; | |
| 142 } else { | |
| 143 return 0; | |
| 144 } | |
| 145 } | |
| 146 | |
| 147 // Next take from the uncommitted region in the other space, and commit it. | |
| 148 tmp_bytes = MIN2(other_space->uncommitted_size(), bytes_needed); | |
| 149 if (tmp_bytes > 0) { | |
| 150 char* const commit_base = committed_high_addr(); | |
| 151 if (other_space->special() || | |
| 152 os::commit_memory(commit_base, tmp_bytes, alignment())) { | |
| 153 // Reduce the reserved region in the other space. | |
| 154 other_space->set_reserved(other_space->reserved_low_addr() + tmp_bytes, | |
| 155 other_space->reserved_high_addr(), | |
| 156 other_space->special()); | |
| 157 | |
| 158 // Grow both reserved and committed in this space. | |
| 159 _reserved_high_addr += tmp_bytes; | |
| 160 _committed_high_addr += tmp_bytes; | |
| 161 bytes_needed -= tmp_bytes; | |
| 162 } else { | |
| 163 return bytes - bytes_needed; | |
| 164 } | |
| 165 } | |
| 166 | |
| 167 // Finally take from the already committed region in the other space. | |
| 168 tmp_bytes = bytes_needed; | |
| 169 if (tmp_bytes > 0) { | |
| 170 // Reduce both committed and reserved in the other space. | |
| 171 other_space->set_committed(other_space->committed_low_addr() + tmp_bytes, | |
| 172 other_space->committed_high_addr()); | |
| 173 other_space->set_reserved(other_space->reserved_low_addr() + tmp_bytes, | |
| 174 other_space->reserved_high_addr(), | |
| 175 other_space->special()); | |
| 176 | |
| 177 // Grow both reserved and committed in this space. | |
| 178 _reserved_high_addr += tmp_bytes; | |
| 179 _committed_high_addr += tmp_bytes; | |
| 180 } | |
| 181 | |
| 182 return bytes; | |
| 183 } | |
| 184 | |
| 185 #ifndef PRODUCT | |
| 186 bool PSVirtualSpace::is_aligned(size_t value, size_t align) { | |
| 187 const size_t tmp_value = value + align - 1; | |
| 188 const size_t mask = ~(align - 1); | |
| 189 return (tmp_value & mask) == value; | |
| 190 } | |
| 191 | |
| 192 bool PSVirtualSpace::is_aligned(size_t value) const { | |
| 193 return is_aligned(value, alignment()); | |
| 194 } | |
| 195 | |
| 196 bool PSVirtualSpace::is_aligned(char* value) const { | |
| 197 return is_aligned((size_t)value); | |
| 198 } | |
| 199 | |
| 200 void PSVirtualSpace::verify() const { | |
| 201 assert(is_aligned(alignment(), os::vm_page_size()), "bad alignment"); | |
| 202 assert(is_aligned(reserved_low_addr()), "bad reserved_low_addr"); | |
| 203 assert(is_aligned(reserved_high_addr()), "bad reserved_high_addr"); | |
| 204 assert(is_aligned(committed_low_addr()), "bad committed_low_addr"); | |
| 205 assert(is_aligned(committed_high_addr()), "bad committed_high_addr"); | |
| 206 | |
| 207 // Reserved region must be non-empty or both addrs must be 0. | |
| 208 assert(reserved_low_addr() < reserved_high_addr() || | |
| 209 reserved_low_addr() == NULL && reserved_high_addr() == NULL, | |
| 210 "bad reserved addrs"); | |
| 211 assert(committed_low_addr() <= committed_high_addr(), "bad committed addrs"); | |
| 212 | |
| 213 if (grows_up()) { | |
| 214 assert(reserved_low_addr() == committed_low_addr(), "bad low addrs"); | |
| 215 assert(reserved_high_addr() >= committed_high_addr(), "bad high addrs"); | |
| 216 } else { | |
| 217 assert(reserved_high_addr() == committed_high_addr(), "bad high addrs"); | |
| 218 assert(reserved_low_addr() <= committed_low_addr(), "bad low addrs"); | |
| 219 } | |
| 220 } | |
| 221 | |
| 222 void PSVirtualSpace::print() const { | |
| 223 gclog_or_tty->print_cr("virtual space [" PTR_FORMAT "]: alignment=" | |
| 224 SIZE_FORMAT "K grows %s%s", | |
| 225 this, alignment() / K, grows_up() ? "up" : "down", | |
| 226 special() ? " (pinned in memory)" : ""); | |
| 227 gclog_or_tty->print_cr(" reserved=" SIZE_FORMAT "K" | |
| 228 " [" PTR_FORMAT "," PTR_FORMAT "]" | |
| 229 " committed=" SIZE_FORMAT "K" | |
| 230 " [" PTR_FORMAT "," PTR_FORMAT "]", | |
| 231 reserved_size() / K, | |
| 232 reserved_low_addr(), reserved_high_addr(), | |
| 233 committed_size() / K, | |
| 234 committed_low_addr(), committed_high_addr()); | |
| 235 } | |
| 236 #endif // #ifndef PRODUCT | |
| 237 | |
| 238 void PSVirtualSpace::print_space_boundaries_on(outputStream* st) const { | |
| 239 st->print_cr(" [" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT ")", | |
| 240 low_boundary(), high(), high_boundary()); | |
| 241 } | |
| 242 | |
| 243 PSVirtualSpaceHighToLow::PSVirtualSpaceHighToLow(ReservedSpace rs, | |
| 244 size_t alignment) : | |
| 245 PSVirtualSpace(alignment) | |
| 246 { | |
| 247 set_reserved(rs); | |
| 248 set_committed(reserved_high_addr(), reserved_high_addr()); | |
| 249 DEBUG_ONLY(verify()); | |
| 250 } | |
| 251 | |
| 252 PSVirtualSpaceHighToLow::PSVirtualSpaceHighToLow(ReservedSpace rs) { | |
| 253 set_reserved(rs); | |
| 254 set_committed(reserved_high_addr(), reserved_high_addr()); | |
| 255 DEBUG_ONLY(verify()); | |
| 256 } | |
| 257 | |
| 258 bool PSVirtualSpaceHighToLow::expand_by(size_t bytes, bool pre_touch) { | |
| 259 assert(is_aligned(bytes), "arg not aligned"); | |
| 260 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 261 | |
| 262 if (uncommitted_size() < bytes) { | |
| 263 return false; | |
| 264 } | |
| 265 | |
| 266 char* const base_addr = committed_low_addr() - bytes; | |
| 267 bool result = special() || os::commit_memory(base_addr, bytes, alignment()); | |
| 268 if (result) { | |
| 269 _committed_low_addr -= bytes; | |
| 270 } | |
| 271 | |
| 272 if (pre_touch || AlwaysPreTouch) { | |
| 273 for (char* curr = base_addr; | |
| 274 curr < _committed_high_addr; | |
| 275 curr += os::vm_page_size()) { | |
| 276 char tmp = *curr; | |
| 277 *curr = 0; | |
| 278 } | |
| 279 } | |
| 280 | |
| 281 return result; | |
| 282 } | |
| 283 | |
| 284 bool PSVirtualSpaceHighToLow::shrink_by(size_t bytes) { | |
| 285 assert(is_aligned(bytes), "arg not aligned"); | |
| 286 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 287 | |
| 288 if (committed_size() < bytes) { | |
| 289 return false; | |
| 290 } | |
| 291 | |
| 292 char* const base_addr = committed_low_addr(); | |
| 293 bool result = special() || os::uncommit_memory(base_addr, bytes); | |
| 294 if (result) { | |
| 295 _committed_low_addr += bytes; | |
| 296 } | |
| 297 | |
| 298 return result; | |
| 299 } | |
| 300 | |
| 301 size_t PSVirtualSpaceHighToLow::expand_into(PSVirtualSpace* other_space, | |
| 302 size_t bytes) { | |
| 303 assert(is_aligned(bytes), "arg not aligned"); | |
| 304 assert(grows_down(), "this space must grow down"); | |
| 305 assert(other_space->grows_up(), "other space must grow up"); | |
| 306 assert(reserved_low_addr() == other_space->reserved_high_addr(), | |
| 307 "spaces not contiguous"); | |
| 308 assert(special() == other_space->special(), "one space is special in memory, the other is not"); | |
| 309 DEBUG_ONLY(PSVirtualSpaceVerifier this_verifier(this)); | |
| 310 DEBUG_ONLY(PSVirtualSpaceVerifier other_verifier(other_space)); | |
| 311 | |
| 312 size_t bytes_needed = bytes; | |
| 313 | |
| 314 // First use the uncommitted region in this space. | |
| 315 size_t tmp_bytes = MIN2(uncommitted_size(), bytes_needed); | |
| 316 if (tmp_bytes > 0) { | |
| 317 if (expand_by(tmp_bytes)) { | |
| 318 bytes_needed -= tmp_bytes; | |
| 319 } else { | |
| 320 return 0; | |
| 321 } | |
| 322 } | |
| 323 | |
| 324 // Next take from the uncommitted region in the other space, and commit it. | |
| 325 tmp_bytes = MIN2(other_space->uncommitted_size(), bytes_needed); | |
| 326 if (tmp_bytes > 0) { | |
| 327 char* const commit_base = committed_low_addr() - tmp_bytes; | |
| 328 if (other_space->special() || | |
| 329 os::commit_memory(commit_base, tmp_bytes, alignment())) { | |
| 330 // Reduce the reserved region in the other space. | |
| 331 other_space->set_reserved(other_space->reserved_low_addr(), | |
| 332 other_space->reserved_high_addr() - tmp_bytes, | |
| 333 other_space->special()); | |
| 334 | |
| 335 // Grow both reserved and committed in this space. | |
| 336 _reserved_low_addr -= tmp_bytes; | |
| 337 _committed_low_addr -= tmp_bytes; | |
| 338 bytes_needed -= tmp_bytes; | |
| 339 } else { | |
| 340 return bytes - bytes_needed; | |
| 341 } | |
| 342 } | |
| 343 | |
| 344 // Finally take from the already committed region in the other space. | |
| 345 tmp_bytes = bytes_needed; | |
| 346 if (tmp_bytes > 0) { | |
| 347 // Reduce both committed and reserved in the other space. | |
| 348 other_space->set_committed(other_space->committed_low_addr(), | |
| 349 other_space->committed_high_addr() - tmp_bytes); | |
| 350 other_space->set_reserved(other_space->reserved_low_addr(), | |
| 351 other_space->reserved_high_addr() - tmp_bytes, | |
| 352 other_space->special()); | |
| 353 | |
| 354 // Grow both reserved and committed in this space. | |
| 355 _reserved_low_addr -= tmp_bytes; | |
| 356 _committed_low_addr -= tmp_bytes; | |
| 357 } | |
| 358 | |
| 359 return bytes; | |
| 360 } | |
| 361 | |
| 362 void | |
| 363 PSVirtualSpaceHighToLow::print_space_boundaries_on(outputStream* st) const { | |
| 364 st->print_cr(" (" PTR_FORMAT ", " PTR_FORMAT ", " PTR_FORMAT "]", | |
| 365 high_boundary(), low(), low_boundary()); | |
| 366 } |