Merge

6983311: G1: LoopTest hangs when run with -XX:+ExplicitInvokesConcurrent Summary: Clear the concurrent marking "in progress" flag while the FullGCCount_lock is held. This avoids a race that can cause back to back System.gc() calls, when ExplicitGCInvokesConcurrent is enabled, to fail to initiate a marking cycle causing the requesting thread to hang. Reviewed-by: tonyp, ysr

6794422: Perm gen expansion policy for concurrent collectors Summary: Concurrent collectors should expand the perm gen without a full STW GC, but possibly by triggering a concurrent collection. Temporary band-aid for G1 where no concurrent collection is kicked off since the perm gen is not collected concurrently. Reviewed-by: johnc

6988678: fatal error deadlock handling was unintentionally disabled Reviewed-by: ysr

6692906: CMS: parallel concurrent marking may be prone to hanging or stalling mutators for periods of time Summary: Inserted missing yield(check)s in closures used during the work-stealing phase of parallel concurrent marking, a missing synchronous yield-request in the cms perm gen allocation path, and a terminator-terminator for the offer_termination invocation that monitors the yield status of the concurrent marking task. Elaborated some documentation comments and made some task queue termination loop flags configurable at start-up to aid debugging in the field. Reviewed-by: jmasa, johnc, poonam

6423256: GC stacks should use a better data structure 6942771: SEGV in ParScanThreadState::take_from_overflow_stack Reviewed-by: apetrusenko, ysr, pbk

6941395: G1: Use only lock-free versions of region stack push() and pop() Summary: Re-enable use of the lock-free versions of region stack push() and pop() by recording aborted regions in a thread-local structure, which are then processed when scanning of the region stack restarts. The previous locking versions of these routines are retained for diagnostic purposes. Reviewed-by: tonyp, ysr

6983296: build sanity checks for jdk7 should require SS12u1 Reviewed-by: ohair

6984287: Regularize how GC parallel workers are specified. Summary: Associate number of GC workers with the workgang as opposed to the task. Reviewed-by: johnc, ysr

Merge