src/share/vm/gc_implementation/shared/markSweep.cpp

Mon, 07 Jul 2014 10:12:40 +0200

author
stefank
date
Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992
2c6ef90f030a
parent 6971
7426d8d76305
child 7535
7ae4e26cb1e0
permissions
-rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

duke@435 1 /*
drchase@6680 2 * Copyright (c) 1997, 2014, 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 "compiler/compileBroker.hpp"
sla@5237 27 #include "gc_implementation/shared/gcTimer.hpp"
sla@5237 28 #include "gc_implementation/shared/gcTrace.hpp"
stefank@2314 29 #include "gc_implementation/shared/markSweep.inline.hpp"
stefank@2314 30 #include "gc_interface/collectedHeap.inline.hpp"
coleenp@4037 31 #include "oops/methodData.hpp"
stefank@2314 32 #include "oops/objArrayKlass.inline.hpp"
stefank@2314 33 #include "oops/oop.inline.hpp"
duke@435 34
drchase@6680 35 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
drchase@6680 36
tschatzl@5119 37 uint MarkSweep::_total_invocations = 0;
coleenp@4037 38
zgu@3900 39 Stack<oop, mtGC> MarkSweep::_marking_stack;
zgu@3900 40 Stack<ObjArrayTask, mtGC> MarkSweep::_objarray_stack;
duke@435 41
zgu@3900 42 Stack<oop, mtGC> MarkSweep::_preserved_oop_stack;
zgu@3900 43 Stack<markOop, mtGC> MarkSweep::_preserved_mark_stack;
duke@435 44 size_t MarkSweep::_preserved_count = 0;
duke@435 45 size_t MarkSweep::_preserved_count_max = 0;
duke@435 46 PreservedMark* MarkSweep::_preserved_marks = NULL;
duke@435 47 ReferenceProcessor* MarkSweep::_ref_processor = NULL;
sla@5237 48 STWGCTimer* MarkSweep::_gc_timer = NULL;
sla@5237 49 SerialOldTracer* MarkSweep::_gc_tracer = NULL;
duke@435 50
coleenp@548 51 MarkSweep::FollowRootClosure MarkSweep::follow_root_closure;
duke@435 52
coleenp@548 53 void MarkSweep::FollowRootClosure::do_oop(oop* p) { follow_root(p); }
coleenp@548 54 void MarkSweep::FollowRootClosure::do_oop(narrowOop* p) { follow_root(p); }
duke@435 55
duke@435 56 MarkSweep::MarkAndPushClosure MarkSweep::mark_and_push_closure;
stefank@6992 57 CLDToOopClosure MarkSweep::follow_cld_closure(&mark_and_push_closure);
stefank@6992 58 CLDToOopClosure MarkSweep::adjust_cld_closure(&adjust_pointer_closure);
duke@435 59
coleenp@4037 60 void MarkSweep::MarkAndPushClosure::do_oop(oop* p) { mark_and_push(p); }
coleenp@548 61 void MarkSweep::MarkAndPushClosure::do_oop(narrowOop* p) { mark_and_push(p); }
duke@435 62
coleenp@4037 63 void MarkSweep::follow_class_loader(ClassLoaderData* cld) {
stefank@6992 64 MarkSweep::follow_cld_closure.do_cld(cld);
coleenp@4037 65 }
coleenp@4037 66
duke@435 67 void MarkSweep::follow_stack() {
jcoomes@1746 68 do {
jcoomes@2191 69 while (!_marking_stack.is_empty()) {
jcoomes@2191 70 oop obj = _marking_stack.pop();
jcoomes@1746 71 assert (obj->is_gc_marked(), "p must be marked");
jcoomes@1746 72 obj->follow_contents();
jcoomes@1746 73 }
jcoomes@1750 74 // Process ObjArrays one at a time to avoid marking stack bloat.
jcoomes@2191 75 if (!_objarray_stack.is_empty()) {
jcoomes@2191 76 ObjArrayTask task = _objarray_stack.pop();
minqi@5097 77 ObjArrayKlass* k = (ObjArrayKlass*)task.obj()->klass();
jcoomes@1746 78 k->oop_follow_contents(task.obj(), task.index());
jcoomes@1746 79 }
jcoomes@2191 80 } while (!_marking_stack.is_empty() || !_objarray_stack.is_empty());
duke@435 81 }
duke@435 82
duke@435 83 MarkSweep::FollowStackClosure MarkSweep::follow_stack_closure;
duke@435 84
coleenp@548 85 void MarkSweep::FollowStackClosure::do_void() { follow_stack(); }
duke@435 86
jcoomes@2191 87 // We preserve the mark which should be replaced at the end and the location
jcoomes@2191 88 // that it will go. Note that the object that this markOop belongs to isn't
jcoomes@2191 89 // currently at that address but it will be after phase4
duke@435 90 void MarkSweep::preserve_mark(oop obj, markOop mark) {
jcoomes@2191 91 // We try to store preserved marks in the to space of the new generation since
jcoomes@2191 92 // this is storage which should be available. Most of the time this should be
jcoomes@2191 93 // sufficient space for the marks we need to preserve but if it isn't we fall
jcoomes@2191 94 // back to using Stacks to keep track of the overflow.
duke@435 95 if (_preserved_count < _preserved_count_max) {
duke@435 96 _preserved_marks[_preserved_count++].init(obj, mark);
duke@435 97 } else {
jcoomes@2191 98 _preserved_mark_stack.push(mark);
jcoomes@2191 99 _preserved_oop_stack.push(obj);
duke@435 100 }
duke@435 101 }
duke@435 102
stefank@5011 103 MarkSweep::AdjustPointerClosure MarkSweep::adjust_pointer_closure;
duke@435 104
stefank@5011 105 void MarkSweep::AdjustPointerClosure::do_oop(oop* p) { adjust_pointer(p); }
stefank@5011 106 void MarkSweep::AdjustPointerClosure::do_oop(narrowOop* p) { adjust_pointer(p); }
coleenp@548 107
duke@435 108 void MarkSweep::adjust_marks() {
jcoomes@2191 109 assert( _preserved_oop_stack.size() == _preserved_mark_stack.size(),
duke@435 110 "inconsistent preserved oop stacks");
duke@435 111
duke@435 112 // adjust the oops we saved earlier
duke@435 113 for (size_t i = 0; i < _preserved_count; i++) {
duke@435 114 _preserved_marks[i].adjust_pointer();
duke@435 115 }
duke@435 116
duke@435 117 // deal with the overflow stack
zgu@3900 118 StackIterator<oop, mtGC> iter(_preserved_oop_stack);
jcoomes@2191 119 while (!iter.is_empty()) {
jcoomes@2191 120 oop* p = iter.next_addr();
jcoomes@2191 121 adjust_pointer(p);
duke@435 122 }
duke@435 123 }
duke@435 124
duke@435 125 void MarkSweep::restore_marks() {
jcoomes@2191 126 assert(_preserved_oop_stack.size() == _preserved_mark_stack.size(),
duke@435 127 "inconsistent preserved oop stacks");
duke@435 128 if (PrintGC && Verbose) {
jcoomes@2191 129 gclog_or_tty->print_cr("Restoring %d marks",
jcoomes@2191 130 _preserved_count + _preserved_oop_stack.size());
duke@435 131 }
duke@435 132
duke@435 133 // restore the marks we saved earlier
duke@435 134 for (size_t i = 0; i < _preserved_count; i++) {
duke@435 135 _preserved_marks[i].restore();
duke@435 136 }
duke@435 137
duke@435 138 // deal with the overflow
jcoomes@2191 139 while (!_preserved_oop_stack.is_empty()) {
jcoomes@2191 140 oop obj = _preserved_oop_stack.pop();
jcoomes@2191 141 markOop mark = _preserved_mark_stack.pop();
jcoomes@2191 142 obj->set_mark(mark);
duke@435 143 }
duke@435 144 }
duke@435 145
coleenp@548 146 MarkSweep::IsAliveClosure MarkSweep::is_alive;
duke@435 147
coleenp@548 148 bool MarkSweep::IsAliveClosure::do_object_b(oop p) { return p->is_gc_marked(); }
duke@435 149
duke@435 150 MarkSweep::KeepAliveClosure MarkSweep::keep_alive;
duke@435 151
coleenp@548 152 void MarkSweep::KeepAliveClosure::do_oop(oop* p) { MarkSweep::KeepAliveClosure::do_oop_work(p); }
coleenp@548 153 void MarkSweep::KeepAliveClosure::do_oop(narrowOop* p) { MarkSweep::KeepAliveClosure::do_oop_work(p); }
coleenp@548 154
sla@5237 155 void marksweep_init() {
sla@5237 156 MarkSweep::_gc_timer = new (ResourceObj::C_HEAP, mtGC) STWGCTimer();
sla@5237 157 MarkSweep::_gc_tracer = new (ResourceObj::C_HEAP, mtGC) SerialOldTracer();
sla@5237 158 }
duke@435 159
duke@435 160 #ifndef PRODUCT
duke@435 161
duke@435 162 void MarkSweep::trace(const char* msg) {
duke@435 163 if (TraceMarkSweep)
duke@435 164 gclog_or_tty->print("%s", msg);
duke@435 165 }
duke@435 166
duke@435 167 #endif

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