8186571: Implementation: JEP 307: Parallel Full GC for G1
Summary: Improve G1 worst-case latencies by making the full GC parallel.
Reviewed-by: tschatzl, sangheki, ehelin
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#ifndef SHARE_GC_G1_G1FULLGCMARKER_HPP
#define SHARE_GC_G1_G1FULLGCMARKER_HPP
#include "gc/g1/g1FullGCOopClosures.hpp"
#include "gc/shared/preservedMarks.hpp"
#include "gc/shared/taskqueue.hpp"
#include "memory/iterator.hpp"
#include "oops/markOop.hpp"
#include "oops/oop.hpp"
#include "runtime/timer.hpp"
#include "utilities/chunkedList.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/stack.hpp"
typedef OverflowTaskQueue<oop, mtGC> OopQueue;
typedef OverflowTaskQueue<ObjArrayTask, mtGC> ObjArrayTaskQueue;
typedef GenericTaskQueueSet<OopQueue, mtGC> OopQueueSet;
typedef GenericTaskQueueSet<ObjArrayTaskQueue, mtGC> ObjArrayTaskQueueSet;
class G1CMBitMap;
class G1FullGCMarker : public CHeapObj<mtGC> {
private:
uint _worker_id;
// Backing mark bitmap
G1CMBitMap* _bitmap;
// Mark stack
OopQueue _oop_stack;
ObjArrayTaskQueue _objarray_stack;
PreservedMarks* _preserved_stack;
// Marking closures
G1MarkAndPushClosure _mark_closure;
G1VerifyOopClosure _verify_closure;
G1FollowStackClosure _stack_closure;
CLDToOopClosure _cld_closure;
inline bool is_empty();
inline bool pop_object(oop& obj);
inline bool pop_objarray(ObjArrayTask& array);
inline void push_objarray(oop obj, size_t index);
inline bool mark_object(oop obj);
// Marking helpers
inline void follow_object(oop obj);
inline void follow_array(objArrayOop array);
inline void follow_array_chunk(objArrayOop array, int index);
public:
G1FullGCMarker(uint worker_id, PreservedMarks* preserved_stack, G1CMBitMap* bitmap);
~G1FullGCMarker();
// Stack getters
OopQueue* oop_stack() { return &_oop_stack; }
ObjArrayTaskQueue* objarray_stack() { return &_objarray_stack; }
PreservedMarks* preserved_stack() { return _preserved_stack; }
// Marking entry points
template <class T> inline void mark_and_push(T* p);
inline void follow_klass(Klass* k);
inline void follow_cld(ClassLoaderData* cld);
inline void drain_stack();
void complete_marking(OopQueueSet* oop_stacks,
ObjArrayTaskQueueSet* array_stacks,
ParallelTaskTerminator* terminator);
// Closure getters
CLDToOopClosure* cld_closure() { return &_cld_closure; }
G1MarkAndPushClosure* mark_closure() { return &_mark_closure; }
G1FollowStackClosure* stack_closure() { return &_stack_closure; }
};
#endif // SHARE_GC_G1_G1FULLGCMARKER_HPP