Tue, 30 Oct 2012 10:23:55 -0700
8000988: VM deadlock when running btree006 on windows-i586
Reviewed-by: johnc, jcoomes, ysr
duke@435 | 1 | /* |
never@3499 | 2 | * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "classfile/javaClasses.hpp" |
stefank@2314 | 27 | #include "classfile/symbolTable.hpp" |
stefank@2314 | 28 | #include "classfile/systemDictionary.hpp" |
stefank@2314 | 29 | #include "classfile/vmSymbols.hpp" |
stefank@2314 | 30 | #include "code/codeCache.hpp" |
stefank@2314 | 31 | #include "code/icBuffer.hpp" |
stefank@2314 | 32 | #include "gc_interface/collectedHeap.inline.hpp" |
stefank@2314 | 33 | #include "memory/genCollectedHeap.hpp" |
stefank@2314 | 34 | #include "memory/genMarkSweep.hpp" |
stefank@2314 | 35 | #include "memory/genOopClosures.inline.hpp" |
stefank@2314 | 36 | #include "memory/generation.inline.hpp" |
stefank@2314 | 37 | #include "memory/modRefBarrierSet.hpp" |
stefank@2314 | 38 | #include "memory/referencePolicy.hpp" |
stefank@2314 | 39 | #include "memory/space.hpp" |
stefank@2314 | 40 | #include "oops/instanceRefKlass.hpp" |
stefank@2314 | 41 | #include "oops/oop.inline.hpp" |
stefank@2314 | 42 | #include "prims/jvmtiExport.hpp" |
stefank@2314 | 43 | #include "runtime/fprofiler.hpp" |
stefank@2314 | 44 | #include "runtime/handles.inline.hpp" |
stefank@2314 | 45 | #include "runtime/synchronizer.hpp" |
stefank@2314 | 46 | #include "runtime/vmThread.hpp" |
stefank@2314 | 47 | #include "utilities/copy.hpp" |
stefank@2314 | 48 | #include "utilities/events.hpp" |
stefank@2314 | 49 | #ifdef TARGET_OS_FAMILY_linux |
stefank@2314 | 50 | # include "thread_linux.inline.hpp" |
stefank@2314 | 51 | #endif |
stefank@2314 | 52 | #ifdef TARGET_OS_FAMILY_solaris |
stefank@2314 | 53 | # include "thread_solaris.inline.hpp" |
stefank@2314 | 54 | #endif |
stefank@2314 | 55 | #ifdef TARGET_OS_FAMILY_windows |
stefank@2314 | 56 | # include "thread_windows.inline.hpp" |
stefank@2314 | 57 | #endif |
never@3156 | 58 | #ifdef TARGET_OS_FAMILY_bsd |
never@3156 | 59 | # include "thread_bsd.inline.hpp" |
never@3156 | 60 | #endif |
duke@435 | 61 | |
duke@435 | 62 | void GenMarkSweep::invoke_at_safepoint(int level, ReferenceProcessor* rp, |
duke@435 | 63 | bool clear_all_softrefs) { |
duke@435 | 64 | assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint"); |
duke@435 | 65 | |
jmasa@1822 | 66 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
jmasa@1822 | 67 | #ifdef ASSERT |
jmasa@1822 | 68 | if (gch->collector_policy()->should_clear_all_soft_refs()) { |
jmasa@1822 | 69 | assert(clear_all_softrefs, "Policy should have been checked earlier"); |
jmasa@1822 | 70 | } |
jmasa@1822 | 71 | #endif |
jmasa@1822 | 72 | |
duke@435 | 73 | // hook up weak ref data so it can be used during Mark-Sweep |
duke@435 | 74 | assert(ref_processor() == NULL, "no stomping"); |
ysr@888 | 75 | assert(rp != NULL, "should be non-NULL"); |
duke@435 | 76 | _ref_processor = rp; |
ysr@892 | 77 | rp->setup_policy(clear_all_softrefs); |
duke@435 | 78 | |
brutisso@3767 | 79 | TraceTime t1(GCCauseString("Full GC", gch->gc_cause()), PrintGC && !PrintGCDetails, true, gclog_or_tty); |
duke@435 | 80 | |
coleenp@4037 | 81 | // When collecting the permanent generation Method*s may be moving, |
duke@435 | 82 | // so we either have to flush all bcp data or convert it into bci. |
duke@435 | 83 | CodeCache::gc_prologue(); |
duke@435 | 84 | Threads::gc_prologue(); |
duke@435 | 85 | |
coleenp@4037 | 86 | // Increment the invocation count |
coleenp@4037 | 87 | _total_invocations++; |
duke@435 | 88 | |
duke@435 | 89 | // Capture heap size before collection for printing. |
duke@435 | 90 | size_t gch_prev_used = gch->used(); |
duke@435 | 91 | |
duke@435 | 92 | // Some of the card table updates below assume that the perm gen is |
duke@435 | 93 | // also being collected. |
duke@435 | 94 | assert(level == gch->n_gens() - 1, |
duke@435 | 95 | "All generations are being collected, ergo perm gen too."); |
duke@435 | 96 | |
duke@435 | 97 | // Capture used regions for each generation that will be |
duke@435 | 98 | // subject to collection, so that card table adjustments can |
duke@435 | 99 | // be made intelligently (see clear / invalidate further below). |
coleenp@4037 | 100 | gch->save_used_regions(level); |
duke@435 | 101 | |
duke@435 | 102 | allocate_stacks(); |
duke@435 | 103 | |
duke@435 | 104 | mark_sweep_phase1(level, clear_all_softrefs); |
duke@435 | 105 | |
duke@435 | 106 | mark_sweep_phase2(); |
duke@435 | 107 | |
duke@435 | 108 | // Don't add any more derived pointers during phase3 |
duke@435 | 109 | COMPILER2_PRESENT(assert(DerivedPointerTable::is_active(), "Sanity")); |
duke@435 | 110 | COMPILER2_PRESENT(DerivedPointerTable::set_active(false)); |
duke@435 | 111 | |
duke@435 | 112 | mark_sweep_phase3(level); |
duke@435 | 113 | |
duke@435 | 114 | VALIDATE_MARK_SWEEP_ONLY( |
duke@435 | 115 | if (ValidateMarkSweep) { |
coleenp@548 | 116 | guarantee(_root_refs_stack->length() == 0, "should be empty by now"); |
duke@435 | 117 | } |
duke@435 | 118 | ) |
duke@435 | 119 | |
duke@435 | 120 | mark_sweep_phase4(); |
duke@435 | 121 | |
duke@435 | 122 | VALIDATE_MARK_SWEEP_ONLY( |
duke@435 | 123 | if (ValidateMarkSweep) { |
duke@435 | 124 | guarantee(_live_oops->length() == _live_oops_moved_to->length(), |
duke@435 | 125 | "should be the same size"); |
duke@435 | 126 | } |
duke@435 | 127 | ) |
duke@435 | 128 | |
duke@435 | 129 | restore_marks(); |
duke@435 | 130 | |
duke@435 | 131 | // Set saved marks for allocation profiler (and other things? -- dld) |
duke@435 | 132 | // (Should this be in general part?) |
duke@435 | 133 | gch->save_marks(); |
duke@435 | 134 | |
duke@435 | 135 | deallocate_stacks(); |
duke@435 | 136 | |
duke@435 | 137 | // If compaction completely evacuated all generations younger than this |
duke@435 | 138 | // one, then we can clear the card table. Otherwise, we must invalidate |
duke@435 | 139 | // it (consider all cards dirty). In the future, we might consider doing |
duke@435 | 140 | // compaction within generations only, and doing card-table sliding. |
duke@435 | 141 | bool all_empty = true; |
duke@435 | 142 | for (int i = 0; all_empty && i < level; i++) { |
duke@435 | 143 | Generation* g = gch->get_gen(i); |
duke@435 | 144 | all_empty = all_empty && gch->get_gen(i)->used() == 0; |
duke@435 | 145 | } |
duke@435 | 146 | GenRemSet* rs = gch->rem_set(); |
duke@435 | 147 | // Clear/invalidate below make use of the "prev_used_regions" saved earlier. |
duke@435 | 148 | if (all_empty) { |
duke@435 | 149 | // We've evacuated all generations below us. |
duke@435 | 150 | Generation* g = gch->get_gen(level); |
coleenp@4037 | 151 | rs->clear_into_younger(g); |
duke@435 | 152 | } else { |
duke@435 | 153 | // Invalidate the cards corresponding to the currently used |
duke@435 | 154 | // region and clear those corresponding to the evacuated region |
duke@435 | 155 | // of all generations just collected (i.e. level and younger). |
duke@435 | 156 | rs->invalidate_or_clear(gch->get_gen(level), |
coleenp@4037 | 157 | true /* younger */); |
duke@435 | 158 | } |
duke@435 | 159 | |
duke@435 | 160 | Threads::gc_epilogue(); |
duke@435 | 161 | CodeCache::gc_epilogue(); |
kamg@2467 | 162 | JvmtiExport::gc_epilogue(); |
duke@435 | 163 | |
duke@435 | 164 | if (PrintGC && !PrintGCDetails) { |
duke@435 | 165 | gch->print_heap_change(gch_prev_used); |
duke@435 | 166 | } |
duke@435 | 167 | |
duke@435 | 168 | // refs processing: clean slate |
duke@435 | 169 | _ref_processor = NULL; |
duke@435 | 170 | |
duke@435 | 171 | // Update heap occupancy information which is used as |
duke@435 | 172 | // input to soft ref clearing policy at the next gc. |
duke@435 | 173 | Universe::update_heap_info_at_gc(); |
duke@435 | 174 | |
duke@435 | 175 | // Update time of last gc for all generations we collected |
duke@435 | 176 | // (which curently is all the generations in the heap). |
johnc@3538 | 177 | // We need to use a monotonically non-deccreasing time in ms |
johnc@3538 | 178 | // or we will see time-warp warnings and os::javaTimeMillis() |
johnc@3538 | 179 | // does not guarantee monotonicity. |
johnc@3538 | 180 | jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC; |
johnc@3538 | 181 | gch->update_time_of_last_gc(now); |
duke@435 | 182 | } |
duke@435 | 183 | |
duke@435 | 184 | void GenMarkSweep::allocate_stacks() { |
duke@435 | 185 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 186 | // Scratch request on behalf of oldest generation; will do no |
duke@435 | 187 | // allocation. |
duke@435 | 188 | ScratchBlock* scratch = gch->gather_scratch(gch->_gens[gch->_n_gens-1], 0); |
duke@435 | 189 | |
duke@435 | 190 | // $$$ To cut a corner, we'll only use the first scratch block, and then |
duke@435 | 191 | // revert to malloc. |
duke@435 | 192 | if (scratch != NULL) { |
duke@435 | 193 | _preserved_count_max = |
duke@435 | 194 | scratch->num_words * HeapWordSize / sizeof(PreservedMark); |
duke@435 | 195 | } else { |
duke@435 | 196 | _preserved_count_max = 0; |
duke@435 | 197 | } |
duke@435 | 198 | |
duke@435 | 199 | _preserved_marks = (PreservedMark*)scratch; |
duke@435 | 200 | _preserved_count = 0; |
duke@435 | 201 | |
duke@435 | 202 | #ifdef VALIDATE_MARK_SWEEP |
duke@435 | 203 | if (ValidateMarkSweep) { |
zgu@3900 | 204 | _root_refs_stack = new (ResourceObj::C_HEAP, mtGC) GrowableArray<void*>(100, true); |
zgu@3900 | 205 | _other_refs_stack = new (ResourceObj::C_HEAP, mtGC) GrowableArray<void*>(100, true); |
zgu@3900 | 206 | _adjusted_pointers = new (ResourceObj::C_HEAP, mtGC) GrowableArray<void*>(100, true); |
zgu@3900 | 207 | _live_oops = new (ResourceObj::C_HEAP, mtGC) GrowableArray<oop>(100, true); |
zgu@3900 | 208 | _live_oops_moved_to = new (ResourceObj::C_HEAP, mtGC) GrowableArray<oop>(100, true); |
zgu@3900 | 209 | _live_oops_size = new (ResourceObj::C_HEAP, mtGC) GrowableArray<size_t>(100, true); |
duke@435 | 210 | } |
duke@435 | 211 | if (RecordMarkSweepCompaction) { |
duke@435 | 212 | if (_cur_gc_live_oops == NULL) { |
zgu@3900 | 213 | _cur_gc_live_oops = new(ResourceObj::C_HEAP, mtGC) GrowableArray<HeapWord*>(100, true); |
zgu@3900 | 214 | _cur_gc_live_oops_moved_to = new(ResourceObj::C_HEAP, mtGC) GrowableArray<HeapWord*>(100, true); |
zgu@3900 | 215 | _cur_gc_live_oops_size = new(ResourceObj::C_HEAP, mtGC) GrowableArray<size_t>(100, true); |
zgu@3900 | 216 | _last_gc_live_oops = new(ResourceObj::C_HEAP, mtGC) GrowableArray<HeapWord*>(100, true); |
zgu@3900 | 217 | _last_gc_live_oops_moved_to = new(ResourceObj::C_HEAP, mtGC) GrowableArray<HeapWord*>(100, true); |
zgu@3900 | 218 | _last_gc_live_oops_size = new(ResourceObj::C_HEAP, mtGC) GrowableArray<size_t>(100, true); |
duke@435 | 219 | } else { |
duke@435 | 220 | _cur_gc_live_oops->clear(); |
duke@435 | 221 | _cur_gc_live_oops_moved_to->clear(); |
duke@435 | 222 | _cur_gc_live_oops_size->clear(); |
duke@435 | 223 | } |
duke@435 | 224 | } |
duke@435 | 225 | #endif |
duke@435 | 226 | } |
duke@435 | 227 | |
duke@435 | 228 | |
duke@435 | 229 | void GenMarkSweep::deallocate_stacks() { |
tonyp@791 | 230 | if (!UseG1GC) { |
tonyp@791 | 231 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
tonyp@791 | 232 | gch->release_scratch(); |
tonyp@791 | 233 | } |
jmasa@698 | 234 | |
jcoomes@2191 | 235 | _preserved_mark_stack.clear(true); |
jcoomes@2191 | 236 | _preserved_oop_stack.clear(true); |
jcoomes@2191 | 237 | _marking_stack.clear(); |
jcoomes@2191 | 238 | _objarray_stack.clear(true); |
duke@435 | 239 | |
duke@435 | 240 | #ifdef VALIDATE_MARK_SWEEP |
duke@435 | 241 | if (ValidateMarkSweep) { |
duke@435 | 242 | delete _root_refs_stack; |
duke@435 | 243 | delete _other_refs_stack; |
duke@435 | 244 | delete _adjusted_pointers; |
duke@435 | 245 | delete _live_oops; |
duke@435 | 246 | delete _live_oops_size; |
duke@435 | 247 | delete _live_oops_moved_to; |
duke@435 | 248 | _live_oops_index = 0; |
duke@435 | 249 | _live_oops_index_at_perm = 0; |
duke@435 | 250 | } |
duke@435 | 251 | #endif |
duke@435 | 252 | } |
duke@435 | 253 | |
duke@435 | 254 | void GenMarkSweep::mark_sweep_phase1(int level, |
duke@435 | 255 | bool clear_all_softrefs) { |
duke@435 | 256 | // Recursively traverse all live objects and mark them |
duke@435 | 257 | TraceTime tm("phase 1", PrintGC && Verbose, true, gclog_or_tty); |
duke@435 | 258 | trace(" 1"); |
duke@435 | 259 | |
coleenp@4037 | 260 | VALIDATE_MARK_SWEEP_ONLY(reset_live_oop_tracking()); |
duke@435 | 261 | |
duke@435 | 262 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 263 | |
duke@435 | 264 | // Because follow_root_closure is created statically, cannot |
duke@435 | 265 | // use OopsInGenClosure constructor which takes a generation, |
duke@435 | 266 | // as the Universe has not been created when the static constructors |
duke@435 | 267 | // are run. |
duke@435 | 268 | follow_root_closure.set_orig_generation(gch->get_gen(level)); |
duke@435 | 269 | |
coleenp@4037 | 270 | // Need new claim bits before marking starts. |
coleenp@4037 | 271 | ClassLoaderDataGraph::clear_claimed_marks(); |
coleenp@4037 | 272 | |
duke@435 | 273 | gch->gen_process_strong_roots(level, |
duke@435 | 274 | false, // Younger gens are not roots. |
jrose@1424 | 275 | true, // activate StrongRootsScope |
coleenp@4037 | 276 | false, // not scavenging |
duke@435 | 277 | SharedHeap::SO_SystemClasses, |
jrose@1424 | 278 | &follow_root_closure, |
jrose@1424 | 279 | true, // walk code active on stacks |
coleenp@4037 | 280 | &follow_root_closure, |
coleenp@4037 | 281 | &follow_klass_closure); |
duke@435 | 282 | |
duke@435 | 283 | // Process reference objects found during marking |
duke@435 | 284 | { |
ysr@892 | 285 | ref_processor()->setup_policy(clear_all_softrefs); |
duke@435 | 286 | ref_processor()->process_discovered_references( |
ysr@888 | 287 | &is_alive, &keep_alive, &follow_stack_closure, NULL); |
duke@435 | 288 | } |
duke@435 | 289 | |
duke@435 | 290 | // Follow system dictionary roots and unload classes |
duke@435 | 291 | bool purged_class = SystemDictionary::do_unloading(&is_alive); |
duke@435 | 292 | |
duke@435 | 293 | // Follow code cache roots |
brutisso@4098 | 294 | CodeCache::do_unloading(&is_alive, purged_class); |
duke@435 | 295 | follow_stack(); // Flush marking stack |
duke@435 | 296 | |
duke@435 | 297 | // Update subklass/sibling/implementor links of live klasses |
coleenp@4037 | 298 | Klass::clean_weak_klass_links(&is_alive); |
jcoomes@2191 | 299 | assert(_marking_stack.is_empty(), "just drained"); |
ysr@1376 | 300 | |
coleenp@2497 | 301 | // Visit interned string tables and delete unmarked oops |
duke@435 | 302 | StringTable::unlink(&is_alive); |
coleenp@2497 | 303 | // Clean up unreferenced symbols in symbol table. |
coleenp@2497 | 304 | SymbolTable::unlink(); |
duke@435 | 305 | |
jcoomes@2191 | 306 | assert(_marking_stack.is_empty(), "stack should be empty by now"); |
duke@435 | 307 | } |
duke@435 | 308 | |
duke@435 | 309 | |
duke@435 | 310 | void GenMarkSweep::mark_sweep_phase2() { |
duke@435 | 311 | // Now all live objects are marked, compute the new object addresses. |
duke@435 | 312 | |
duke@435 | 313 | // It is imperative that we traverse perm_gen LAST. If dead space is |
duke@435 | 314 | // allowed a range of dead object may get overwritten by a dead int |
coleenp@4037 | 315 | // array. If perm_gen is not traversed last a Klass* may get |
duke@435 | 316 | // overwritten. This is fine since it is dead, but if the class has dead |
duke@435 | 317 | // instances we have to skip them, and in order to find their size we |
coleenp@4037 | 318 | // need the Klass*! |
duke@435 | 319 | // |
duke@435 | 320 | // It is not required that we traverse spaces in the same order in |
duke@435 | 321 | // phase2, phase3 and phase4, but the ValidateMarkSweep live oops |
duke@435 | 322 | // tracking expects us to do so. See comment under phase4. |
duke@435 | 323 | |
duke@435 | 324 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 325 | |
duke@435 | 326 | TraceTime tm("phase 2", PrintGC && Verbose, true, gclog_or_tty); |
duke@435 | 327 | trace("2"); |
duke@435 | 328 | |
coleenp@4037 | 329 | VALIDATE_MARK_SWEEP_ONLY(reset_live_oop_tracking()); |
duke@435 | 330 | |
duke@435 | 331 | gch->prepare_for_compaction(); |
duke@435 | 332 | } |
duke@435 | 333 | |
duke@435 | 334 | class GenAdjustPointersClosure: public GenCollectedHeap::GenClosure { |
duke@435 | 335 | public: |
duke@435 | 336 | void do_generation(Generation* gen) { |
duke@435 | 337 | gen->adjust_pointers(); |
duke@435 | 338 | } |
duke@435 | 339 | }; |
duke@435 | 340 | |
duke@435 | 341 | void GenMarkSweep::mark_sweep_phase3(int level) { |
duke@435 | 342 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 343 | |
duke@435 | 344 | // Adjust the pointers to reflect the new locations |
duke@435 | 345 | TraceTime tm("phase 3", PrintGC && Verbose, true, gclog_or_tty); |
duke@435 | 346 | trace("3"); |
duke@435 | 347 | |
coleenp@4037 | 348 | // Need new claim bits for the pointer adjustment tracing. |
coleenp@4037 | 349 | ClassLoaderDataGraph::clear_claimed_marks(); |
duke@435 | 350 | |
coleenp@4037 | 351 | VALIDATE_MARK_SWEEP_ONLY(reset_live_oop_tracking()); |
duke@435 | 352 | |
duke@435 | 353 | // Because the two closures below are created statically, cannot |
duke@435 | 354 | // use OopsInGenClosure constructor which takes a generation, |
duke@435 | 355 | // as the Universe has not been created when the static constructors |
duke@435 | 356 | // are run. |
duke@435 | 357 | adjust_root_pointer_closure.set_orig_generation(gch->get_gen(level)); |
duke@435 | 358 | adjust_pointer_closure.set_orig_generation(gch->get_gen(level)); |
duke@435 | 359 | |
duke@435 | 360 | gch->gen_process_strong_roots(level, |
duke@435 | 361 | false, // Younger gens are not roots. |
jrose@1424 | 362 | true, // activate StrongRootsScope |
coleenp@4037 | 363 | false, // not scavenging |
duke@435 | 364 | SharedHeap::SO_AllClasses, |
duke@435 | 365 | &adjust_root_pointer_closure, |
jrose@1424 | 366 | false, // do not walk code |
coleenp@4037 | 367 | &adjust_root_pointer_closure, |
coleenp@4037 | 368 | &adjust_klass_closure); |
duke@435 | 369 | |
duke@435 | 370 | // Now adjust pointers in remaining weak roots. (All of which should |
duke@435 | 371 | // have been cleared if they pointed to non-surviving objects.) |
jrose@1424 | 372 | CodeBlobToOopClosure adjust_code_pointer_closure(&adjust_pointer_closure, |
jrose@1424 | 373 | /*do_marking=*/ false); |
duke@435 | 374 | gch->gen_process_weak_roots(&adjust_root_pointer_closure, |
jrose@1424 | 375 | &adjust_code_pointer_closure, |
duke@435 | 376 | &adjust_pointer_closure); |
duke@435 | 377 | |
duke@435 | 378 | adjust_marks(); |
duke@435 | 379 | GenAdjustPointersClosure blk; |
duke@435 | 380 | gch->generation_iterate(&blk, true); |
duke@435 | 381 | } |
duke@435 | 382 | |
duke@435 | 383 | class GenCompactClosure: public GenCollectedHeap::GenClosure { |
duke@435 | 384 | public: |
duke@435 | 385 | void do_generation(Generation* gen) { |
duke@435 | 386 | gen->compact(); |
duke@435 | 387 | } |
duke@435 | 388 | }; |
duke@435 | 389 | |
duke@435 | 390 | void GenMarkSweep::mark_sweep_phase4() { |
duke@435 | 391 | // All pointers are now adjusted, move objects accordingly |
duke@435 | 392 | |
duke@435 | 393 | // It is imperative that we traverse perm_gen first in phase4. All |
duke@435 | 394 | // classes must be allocated earlier than their instances, and traversing |
coleenp@4037 | 395 | // perm_gen first makes sure that all Klass*s have moved to their new |
duke@435 | 396 | // location before any instance does a dispatch through it's klass! |
duke@435 | 397 | |
duke@435 | 398 | // The ValidateMarkSweep live oops tracking expects us to traverse spaces |
duke@435 | 399 | // in the same order in phase2, phase3 and phase4. We don't quite do that |
duke@435 | 400 | // here (perm_gen first rather than last), so we tell the validate code |
duke@435 | 401 | // to use a higher index (saved from phase2) when verifying perm_gen. |
duke@435 | 402 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 403 | |
duke@435 | 404 | TraceTime tm("phase 4", PrintGC && Verbose, true, gclog_or_tty); |
duke@435 | 405 | trace("4"); |
duke@435 | 406 | |
coleenp@4037 | 407 | VALIDATE_MARK_SWEEP_ONLY(reset_live_oop_tracking()); |
duke@435 | 408 | |
duke@435 | 409 | GenCompactClosure blk; |
duke@435 | 410 | gch->generation_iterate(&blk, true); |
duke@435 | 411 | |
duke@435 | 412 | VALIDATE_MARK_SWEEP_ONLY(compaction_complete()); |
duke@435 | 413 | } |