Removed the HeapRegion::_top_at_conc_mark_count field. It is no longer needed as a result of the changes for 6888336 and 7127706. Refactored the closures that finalize and verify the liveness counting data so that common functionality was placed into a base class.
Reviewed-by: brutisso, tonyp
Re-enable survivors during the initial-mark pause. Afterwards, the concurrent marking threads have to scan them and mark everything reachable from them. The next GC will have to wait for the survivors to be scanned.
Reviewed-by: brutisso, johnc
This change simplifies the interaction between GC and concurrent marking. By disabling survivor spaces during the initial-mark pause we don't need to propagate marks of objects we copy during each GC (since we never need to copy an explicitly marked object).
Reviewed-by: johnc, brutisso
7023151: G1: refactor the code that operates on _cur_alloc_region to be re-used for allocs by the GC threads
7018286: G1: humongous allocation attempts should take the GC locker into account
First, this change replaces the asymmetric locking scheme in the G1 slow alloc path by a summetric one. Second, it factors out the code that operates on _cur_alloc_region so that it can be re-used for allocations by the GC threads in the future.
Reviewed-by: stefank, brutisso, johnc
