duke@435: /* coleenp@4037: * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. duke@435: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. duke@435: * duke@435: * This code is free software; you can redistribute it and/or modify it duke@435: * under the terms of the GNU General Public License version 2 only, as duke@435: * published by the Free Software Foundation. duke@435: * duke@435: * This code is distributed in the hope that it will be useful, but WITHOUT duke@435: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or duke@435: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License duke@435: * version 2 for more details (a copy is included in the LICENSE file that duke@435: * accompanied this code). duke@435: * duke@435: * You should have received a copy of the GNU General Public License version duke@435: * 2 along with this work; if not, write to the Free Software Foundation, duke@435: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. duke@435: * trims@1907: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA trims@1907: * or visit www.oracle.com if you need additional information or have any trims@1907: * questions. duke@435: * duke@435: */ duke@435: stefank@2314: #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP stefank@2314: #define SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP stefank@2314: stefank@2314: #include "gc_interface/collectedHeap.hpp" stefank@2314: #include "memory/universe.hpp" stefank@2314: #include "oops/markOop.hpp" stefank@2314: #include "oops/oop.hpp" stefank@2314: #include "runtime/timer.hpp" stefank@2314: #include "utilities/growableArray.hpp" stefank@2314: #include "utilities/stack.hpp" stefank@2314: #include "utilities/taskqueue.hpp" stefank@2314: duke@435: class ReferenceProcessor; ysr@1376: class DataLayout; duke@435: duke@435: // MarkSweep takes care of global mark-compact garbage collection for a duke@435: // GenCollectedHeap using a four-phase pointer forwarding algorithm. All duke@435: // generations are assumed to support marking; those that can also support duke@435: // compaction. duke@435: // duke@435: // Class unloading will only occur when a full gc is invoked. duke@435: duke@435: // If VALIDATE_MARK_SWEEP is defined, the -XX:+ValidateMarkSweep flag will duke@435: // be operational, and will provide slow but comprehensive self-checks within duke@435: // the GC. This is not enabled by default in product or release builds, duke@435: // since the extra call to track_adjusted_pointer() in _adjust_pointer() duke@435: // would be too much overhead, and would disturb performance measurement. duke@435: // However, debug builds are sometimes way too slow to run GC tests! duke@435: #ifdef ASSERT duke@435: #define VALIDATE_MARK_SWEEP 1 duke@435: #endif duke@435: #ifdef VALIDATE_MARK_SWEEP duke@435: #define VALIDATE_MARK_SWEEP_ONLY(code) code duke@435: #else duke@435: #define VALIDATE_MARK_SWEEP_ONLY(code) duke@435: #endif duke@435: duke@435: // declared at end duke@435: class PreservedMark; duke@435: duke@435: class MarkSweep : AllStatic { duke@435: // coleenp@548: // Inline closure decls duke@435: // coleenp@548: class FollowRootClosure: public OopsInGenClosure { duke@435: public: coleenp@548: virtual void do_oop(oop* p); coleenp@548: virtual void do_oop(narrowOop* p); duke@435: }; duke@435: duke@435: class MarkAndPushClosure: public OopClosure { duke@435: public: coleenp@548: virtual void do_oop(oop* p); coleenp@548: virtual void do_oop(narrowOop* p); coleenp@4037: }; coleenp@4037: coleenp@4037: // The one and only place to start following the classes. coleenp@4037: // Should only be applied to the ClassLoaderData klasses list. coleenp@4037: class FollowKlassClosure : public KlassClosure { coleenp@4037: public: coleenp@4037: void do_klass(Klass* klass); coleenp@4037: }; coleenp@4037: class AdjustKlassClosure : public KlassClosure { coleenp@4037: public: coleenp@4037: void do_klass(Klass* klass); duke@435: }; duke@435: duke@435: class FollowStackClosure: public VoidClosure { duke@435: public: coleenp@548: virtual void do_void(); duke@435: }; duke@435: duke@435: class AdjustPointerClosure: public OopsInGenClosure { coleenp@548: private: duke@435: bool _is_root; duke@435: public: duke@435: AdjustPointerClosure(bool is_root) : _is_root(is_root) {} coleenp@548: virtual void do_oop(oop* p); coleenp@548: virtual void do_oop(narrowOop* p); duke@435: }; duke@435: duke@435: // Used for java/lang/ref handling duke@435: class IsAliveClosure: public BoolObjectClosure { duke@435: public: coleenp@548: virtual void do_object(oop p); coleenp@548: virtual bool do_object_b(oop p); duke@435: }; duke@435: duke@435: class KeepAliveClosure: public OopClosure { coleenp@548: protected: coleenp@548: template void do_oop_work(T* p); duke@435: public: coleenp@548: virtual void do_oop(oop* p); coleenp@548: virtual void do_oop(narrowOop* p); duke@435: }; duke@435: duke@435: // duke@435: // Friend decls duke@435: // duke@435: friend class AdjustPointerClosure; duke@435: friend class KeepAliveClosure; duke@435: friend class VM_MarkSweep; duke@435: friend void marksweep_init(); duke@435: duke@435: // duke@435: // Vars duke@435: // duke@435: protected: coleenp@4037: // Total invocations of a MarkSweep collection coleenp@4037: static unsigned int _total_invocations; coleenp@4037: jcoomes@1746: // Traversal stacks used during phase1 zgu@3900: static Stack _marking_stack; zgu@3900: static Stack _objarray_stack; duke@435: duke@435: // Space for storing/restoring mark word zgu@3900: static Stack _preserved_mark_stack; zgu@3900: static Stack _preserved_oop_stack; duke@435: static size_t _preserved_count; duke@435: static size_t _preserved_count_max; duke@435: static PreservedMark* _preserved_marks; duke@435: duke@435: // Reference processing (used in ...follow_contents) duke@435: static ReferenceProcessor* _ref_processor; duke@435: duke@435: #ifdef VALIDATE_MARK_SWEEP coleenp@548: static GrowableArray* _root_refs_stack; duke@435: static GrowableArray * _live_oops; duke@435: static GrowableArray * _live_oops_moved_to; duke@435: static GrowableArray* _live_oops_size; duke@435: static size_t _live_oops_index; duke@435: static size_t _live_oops_index_at_perm; coleenp@548: static GrowableArray* _other_refs_stack; coleenp@548: static GrowableArray* _adjusted_pointers; duke@435: static bool _pointer_tracking; duke@435: static bool _root_tracking; duke@435: duke@435: // The following arrays are saved since the time of the last GC and duke@435: // assist in tracking down problems where someone has done an errant duke@435: // store into the heap, usually to an oop that wasn't properly duke@435: // handleized across a GC. If we crash or otherwise fail before the duke@435: // next GC, we can query these arrays to find out the object we had duke@435: // intended to do the store to (assuming it is still alive) and the duke@435: // offset within that object. Covered under RecordMarkSweepCompaction. duke@435: static GrowableArray * _cur_gc_live_oops; duke@435: static GrowableArray * _cur_gc_live_oops_moved_to; duke@435: static GrowableArray* _cur_gc_live_oops_size; duke@435: static GrowableArray * _last_gc_live_oops; duke@435: static GrowableArray * _last_gc_live_oops_moved_to; duke@435: static GrowableArray* _last_gc_live_oops_size; duke@435: #endif duke@435: duke@435: // Non public closures duke@435: static KeepAliveClosure keep_alive; duke@435: duke@435: // Debugging duke@435: static void trace(const char* msg) PRODUCT_RETURN; duke@435: duke@435: public: duke@435: // Public closures coleenp@4037: static IsAliveClosure is_alive; coleenp@548: static FollowRootClosure follow_root_closure; jrose@1424: static CodeBlobToOopClosure follow_code_root_closure; // => follow_root_closure coleenp@548: static MarkAndPushClosure mark_and_push_closure; coleenp@4037: static FollowKlassClosure follow_klass_closure; coleenp@548: static FollowStackClosure follow_stack_closure; duke@435: static AdjustPointerClosure adjust_root_pointer_closure; duke@435: static AdjustPointerClosure adjust_pointer_closure; coleenp@4037: static AdjustKlassClosure adjust_klass_closure; coleenp@4037: coleenp@4037: // Accessors coleenp@4037: static unsigned int total_invocations() { return _total_invocations; } duke@435: duke@435: // Reference Processing duke@435: static ReferenceProcessor* const ref_processor() { return _ref_processor; } duke@435: duke@435: // Call backs for marking duke@435: static void mark_object(oop obj); coleenp@548: // Mark pointer and follow contents. Empty marking stack afterwards. coleenp@548: template static inline void follow_root(T* p); coleenp@4037: coleenp@548: // Check mark and maybe push on marking stack coleenp@4037: template static void mark_and_push(T* p); coleenp@4037: jcoomes@1746: static inline void push_objarray(oop obj, size_t index); duke@435: coleenp@548: static void follow_stack(); // Empty marking stack. duke@435: coleenp@4037: static void follow_klass(Klass* klass); coleenp@4037: static void adjust_klass(Klass* klass); coleenp@4037: coleenp@4037: static void follow_class_loader(ClassLoaderData* cld); coleenp@4037: static void adjust_class_loader(ClassLoaderData* cld); coleenp@4037: coleenp@548: static void preserve_mark(oop p, markOop mark); coleenp@548: // Save the mark word so it can be restored later coleenp@548: static void adjust_marks(); // Adjust the pointers in the preserved marks table coleenp@548: static void restore_marks(); // Restore the marks that we saved in preserve_mark duke@435: coleenp@548: template static inline void adjust_pointer(T* p, bool isroot); duke@435: coleenp@548: static void adjust_root_pointer(oop* p) { adjust_pointer(p, true); } coleenp@548: static void adjust_pointer(oop* p) { adjust_pointer(p, false); } coleenp@548: static void adjust_pointer(narrowOop* p) { adjust_pointer(p, false); } duke@435: duke@435: #ifdef VALIDATE_MARK_SWEEP coleenp@548: static void track_adjusted_pointer(void* p, bool isroot); coleenp@548: static void check_adjust_pointer(void* p); duke@435: static void track_interior_pointers(oop obj); duke@435: static void check_interior_pointers(); duke@435: coleenp@4037: static void reset_live_oop_tracking(); duke@435: static void register_live_oop(oop p, size_t size); duke@435: static void validate_live_oop(oop p, size_t size); duke@435: static void live_oop_moved_to(HeapWord* q, size_t size, HeapWord* compaction_top); duke@435: static void compaction_complete(); duke@435: duke@435: // Querying operation of RecordMarkSweepCompaction results. duke@435: // Finds and prints the current base oop and offset for a word duke@435: // within an oop that was live during the last GC. Helpful for duke@435: // tracking down heap stomps. duke@435: static void print_new_location_of_heap_address(HeapWord* q); duke@435: #endif duke@435: }; duke@435: duke@435: class PreservedMark VALUE_OBJ_CLASS_SPEC { duke@435: private: duke@435: oop _obj; duke@435: markOop _mark; duke@435: duke@435: public: duke@435: void init(oop obj, markOop mark) { duke@435: _obj = obj; duke@435: _mark = mark; duke@435: } duke@435: duke@435: void adjust_pointer() { duke@435: MarkSweep::adjust_pointer(&_obj); duke@435: } duke@435: duke@435: void restore() { duke@435: _obj->set_mark(_mark); duke@435: } duke@435: }; stefank@2314: stefank@2314: #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_MARKSWEEP_HPP