1.1 --- a/src/share/vm/gc_implementation/g1/heapRegion.hpp Tue Mar 29 22:36:16 2011 -0400
1.2 +++ b/src/share/vm/gc_implementation/g1/heapRegion.hpp Wed Mar 30 10:26:59 2011 -0400
1.3 @@ -149,6 +149,13 @@
1.4 G1BlockOffsetArrayContigSpace _offsets;
1.5 Mutex _par_alloc_lock;
1.6 volatile unsigned _gc_time_stamp;
1.7 + // When we need to retire an allocation region, while other threads
1.8 + // are also concurrently trying to allocate into it, we typically
1.9 + // allocate a dummy object at the end of the region to ensure that
1.10 + // no more allocations can take place in it. However, sometimes we
1.11 + // want to know where the end of the last "real" object we allocated
1.12 + // into the region was and this is what this keeps track.
1.13 + HeapWord* _pre_dummy_top;
1.14
1.15 public:
1.16 // Constructor. If "is_zeroed" is true, the MemRegion "mr" may be
1.17 @@ -163,6 +170,17 @@
1.18 virtual void set_saved_mark();
1.19 void reset_gc_time_stamp() { _gc_time_stamp = 0; }
1.20
1.21 + // See the comment above in the declaration of _pre_dummy_top for an
1.22 + // explanation of what it is.
1.23 + void set_pre_dummy_top(HeapWord* pre_dummy_top) {
1.24 + assert(is_in(pre_dummy_top) && pre_dummy_top <= top(), "pre-condition");
1.25 + _pre_dummy_top = pre_dummy_top;
1.26 + }
1.27 + HeapWord* pre_dummy_top() {
1.28 + return (_pre_dummy_top == NULL) ? top() : _pre_dummy_top;
1.29 + }
1.30 + void reset_pre_dummy_top() { _pre_dummy_top = NULL; }
1.31 +
1.32 virtual void initialize(MemRegion mr, bool clear_space, bool mangle_space);
1.33 virtual void clear(bool mangle_space);
1.34
