diff -r 2dd52dea6d28 -r 7b0e9cba0307 src/share/vm/gc_interface/collectedHeap.hpp --- a/src/share/vm/gc_interface/collectedHeap.hpp Tue Jan 12 14:56:46 2010 -0800 +++ b/src/share/vm/gc_interface/collectedHeap.hpp Wed Jan 13 15:26:39 2010 -0800 @@ -51,6 +51,9 @@ // Used for filler objects (static, but initialized in ctor). static size_t _filler_array_max_size; + // Used in support of ReduceInitialCardMarks; only consulted if COMPILER2 is being used + bool _defer_initial_card_mark; + protected: MemRegion _reserved; BarrierSet* _barrier_set; @@ -70,13 +73,16 @@ // Constructor CollectedHeap(); + // Do common initializations that must follow instance construction, + // for example, those needing virtual calls. + // This code could perhaps be moved into initialize() but would + // be slightly more awkward because we want the latter to be a + // pure virtual. + void pre_initialize(); + // Create a new tlab virtual HeapWord* allocate_new_tlab(size_t size); - // Fix up tlabs to make the heap well-formed again, - // optionally retiring the tlabs. - virtual void fill_all_tlabs(bool retire); - // Accumulate statistics on all tlabs. virtual void accumulate_statistics_all_tlabs(); @@ -431,14 +437,25 @@ // promises to call this function on such a slow-path-allocated // object before performing initializations that have elided // store barriers. Returns new_obj, or maybe a safer copy thereof. - virtual oop defer_store_barrier(JavaThread* thread, oop new_obj); + virtual oop new_store_pre_barrier(JavaThread* thread, oop new_obj); // Answers whether an initializing store to a new object currently - // allocated at the given address doesn't need a (deferred) store + // allocated at the given address doesn't need a store // barrier. Returns "true" if it doesn't need an initializing // store barrier; answers "false" if it does. virtual bool can_elide_initializing_store_barrier(oop new_obj) = 0; + // If a compiler is eliding store barriers for TLAB-allocated objects, + // we will be informed of a slow-path allocation by a call + // to new_store_pre_barrier() above. Such a call precedes the + // initialization of the object itself, and no post-store-barriers will + // be issued. Some heap types require that the barrier strictly follows + // the initializing stores. (This is currently implemented by deferring the + // barrier until the next slow-path allocation or gc-related safepoint.) + // This interface answers whether a particular heap type needs the card + // mark to be thus strictly sequenced after the stores. + virtual bool card_mark_must_follow_store() const = 0; + // If the CollectedHeap was asked to defer a store barrier above, // this informs it to flush such a deferred store barrier to the // remembered set.