7182260: G1: Fine grain RSet freeing bottleneck
Summary: Chain the fine grain PerRegionTables in an individual RSet together and free them in bulk using a single operation.
Reviewed-by: johnc, brutisso
Contributed-by: Thomas Schatzl <thomas.schatzl@jku.at>
7184772: G1: Incorrect assert in HeapRegionLinkedList::add_as_head()
Summary: Assertion incorrectly checks that _head is NULL and should be checking that _tail is NULL instead.
Reviewed-by: johnc
Contributed-by: Brandon Mitchell <brandon@twitter.com>