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

Tue, 18 Mar 2014 19:07:22 +0100

author
pliden
date
Tue, 18 Mar 2014 19:07:22 +0100
changeset 6413
595c0f60d50d
parent 6148
55a0da3d420b
child 6876
710a3c8b516e
child 6971
7426d8d76305
permissions
-rw-r--r--

8029075: String deduplication in G1
Summary: Implementation of JEP 192, http://openjdk.java.net/jeps/192
Reviewed-by: brutisso, tschatzl, coleenp

duke@435 1 /*
sla@5237 2 * Copyright (c) 1997, 2013, 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 #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP
stefank@2314 26 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP
stefank@2314 27
stefank@2314 28 #include "gc_interface/collectedHeap.hpp"
stefank@2314 29 #include "memory/universe.hpp"
stefank@2314 30 #include "oops/markOop.hpp"
stefank@2314 31 #include "oops/oop.hpp"
stefank@2314 32 #include "runtime/timer.hpp"
stefank@2314 33 #include "utilities/growableArray.hpp"
stefank@2314 34 #include "utilities/stack.hpp"
stefank@2314 35 #include "utilities/taskqueue.hpp"
stefank@2314 36
duke@435 37 class ReferenceProcessor;
ysr@1376 38 class DataLayout;
sla@5237 39 class SerialOldTracer;
sla@5237 40 class STWGCTimer;
duke@435 41
duke@435 42 // MarkSweep takes care of global mark-compact garbage collection for a
duke@435 43 // GenCollectedHeap using a four-phase pointer forwarding algorithm. All
duke@435 44 // generations are assumed to support marking; those that can also support
duke@435 45 // compaction.
duke@435 46 //
duke@435 47 // Class unloading will only occur when a full gc is invoked.
duke@435 48
duke@435 49 // declared at end
duke@435 50 class PreservedMark;
duke@435 51
duke@435 52 class MarkSweep : AllStatic {
duke@435 53 //
coleenp@548 54 // Inline closure decls
duke@435 55 //
coleenp@548 56 class FollowRootClosure: public OopsInGenClosure {
duke@435 57 public:
coleenp@548 58 virtual void do_oop(oop* p);
coleenp@548 59 virtual void do_oop(narrowOop* p);
duke@435 60 };
duke@435 61
duke@435 62 class MarkAndPushClosure: public OopClosure {
duke@435 63 public:
coleenp@548 64 virtual void do_oop(oop* p);
coleenp@548 65 virtual void do_oop(narrowOop* p);
coleenp@4037 66 };
coleenp@4037 67
coleenp@4037 68 // The one and only place to start following the classes.
coleenp@4037 69 // Should only be applied to the ClassLoaderData klasses list.
coleenp@4037 70 class FollowKlassClosure : public KlassClosure {
coleenp@4037 71 public:
coleenp@4037 72 void do_klass(Klass* klass);
coleenp@4037 73 };
coleenp@4037 74 class AdjustKlassClosure : public KlassClosure {
coleenp@4037 75 public:
coleenp@4037 76 void do_klass(Klass* klass);
duke@435 77 };
duke@435 78
duke@435 79 class FollowStackClosure: public VoidClosure {
duke@435 80 public:
coleenp@548 81 virtual void do_void();
duke@435 82 };
duke@435 83
duke@435 84 class AdjustPointerClosure: public OopsInGenClosure {
duke@435 85 public:
coleenp@548 86 virtual void do_oop(oop* p);
coleenp@548 87 virtual void do_oop(narrowOop* p);
duke@435 88 };
duke@435 89
duke@435 90 // Used for java/lang/ref handling
duke@435 91 class IsAliveClosure: public BoolObjectClosure {
duke@435 92 public:
coleenp@548 93 virtual bool do_object_b(oop p);
duke@435 94 };
duke@435 95
duke@435 96 class KeepAliveClosure: public OopClosure {
coleenp@548 97 protected:
coleenp@548 98 template <class T> void do_oop_work(T* p);
duke@435 99 public:
coleenp@548 100 virtual void do_oop(oop* p);
coleenp@548 101 virtual void do_oop(narrowOop* p);
duke@435 102 };
duke@435 103
duke@435 104 //
duke@435 105 // Friend decls
duke@435 106 //
duke@435 107 friend class AdjustPointerClosure;
duke@435 108 friend class KeepAliveClosure;
duke@435 109 friend class VM_MarkSweep;
duke@435 110 friend void marksweep_init();
duke@435 111
duke@435 112 //
duke@435 113 // Vars
duke@435 114 //
duke@435 115 protected:
coleenp@4037 116 // Total invocations of a MarkSweep collection
tschatzl@5119 117 static uint _total_invocations;
coleenp@4037 118
jcoomes@1746 119 // Traversal stacks used during phase1
zgu@3900 120 static Stack<oop, mtGC> _marking_stack;
zgu@3900 121 static Stack<ObjArrayTask, mtGC> _objarray_stack;
duke@435 122
duke@435 123 // Space for storing/restoring mark word
zgu@3900 124 static Stack<markOop, mtGC> _preserved_mark_stack;
zgu@3900 125 static Stack<oop, mtGC> _preserved_oop_stack;
duke@435 126 static size_t _preserved_count;
duke@435 127 static size_t _preserved_count_max;
duke@435 128 static PreservedMark* _preserved_marks;
duke@435 129
duke@435 130 // Reference processing (used in ...follow_contents)
duke@435 131 static ReferenceProcessor* _ref_processor;
duke@435 132
sla@5237 133 static STWGCTimer* _gc_timer;
sla@5237 134 static SerialOldTracer* _gc_tracer;
sla@5237 135
duke@435 136 // Non public closures
duke@435 137 static KeepAliveClosure keep_alive;
duke@435 138
duke@435 139 // Debugging
duke@435 140 static void trace(const char* msg) PRODUCT_RETURN;
duke@435 141
duke@435 142 public:
duke@435 143 // Public closures
coleenp@4037 144 static IsAliveClosure is_alive;
coleenp@548 145 static FollowRootClosure follow_root_closure;
jrose@1424 146 static CodeBlobToOopClosure follow_code_root_closure; // => follow_root_closure
coleenp@548 147 static MarkAndPushClosure mark_and_push_closure;
coleenp@4037 148 static FollowKlassClosure follow_klass_closure;
coleenp@548 149 static FollowStackClosure follow_stack_closure;
duke@435 150 static AdjustPointerClosure adjust_pointer_closure;
coleenp@4037 151 static AdjustKlassClosure adjust_klass_closure;
coleenp@4037 152
coleenp@4037 153 // Accessors
tschatzl@5119 154 static uint total_invocations() { return _total_invocations; }
duke@435 155
duke@435 156 // Reference Processing
duke@435 157 static ReferenceProcessor* const ref_processor() { return _ref_processor; }
duke@435 158
sla@5237 159 static STWGCTimer* gc_timer() { return _gc_timer; }
sla@5237 160 static SerialOldTracer* gc_tracer() { return _gc_tracer; }
sla@5237 161
duke@435 162 // Call backs for marking
duke@435 163 static void mark_object(oop obj);
coleenp@548 164 // Mark pointer and follow contents. Empty marking stack afterwards.
coleenp@548 165 template <class T> static inline void follow_root(T* p);
coleenp@4037 166
coleenp@548 167 // Check mark and maybe push on marking stack
coleenp@4037 168 template <class T> static void mark_and_push(T* p);
coleenp@4037 169
jcoomes@1746 170 static inline void push_objarray(oop obj, size_t index);
duke@435 171
coleenp@548 172 static void follow_stack(); // Empty marking stack.
duke@435 173
coleenp@4037 174 static void follow_klass(Klass* klass);
coleenp@4037 175
coleenp@4037 176 static void follow_class_loader(ClassLoaderData* cld);
coleenp@4037 177
coleenp@548 178 static void preserve_mark(oop p, markOop mark);
coleenp@548 179 // Save the mark word so it can be restored later
coleenp@548 180 static void adjust_marks(); // Adjust the pointers in the preserved marks table
coleenp@548 181 static void restore_marks(); // Restore the marks that we saved in preserve_mark
duke@435 182
stefank@5011 183 template <class T> static inline void adjust_pointer(T* p);
duke@435 184 };
duke@435 185
duke@435 186 class PreservedMark VALUE_OBJ_CLASS_SPEC {
duke@435 187 private:
duke@435 188 oop _obj;
duke@435 189 markOop _mark;
duke@435 190
duke@435 191 public:
duke@435 192 void init(oop obj, markOop mark) {
duke@435 193 _obj = obj;
duke@435 194 _mark = mark;
duke@435 195 }
duke@435 196
duke@435 197 void adjust_pointer() {
duke@435 198 MarkSweep::adjust_pointer(&_obj);
duke@435 199 }
duke@435 200
duke@435 201 void restore() {
duke@435 202 _obj->set_mark(_mark);
duke@435 203 }
duke@435 204 };
stefank@2314 205
stefank@2314 206 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP

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