7143858: G1: Back to back young GCs with the second GC having a minimally sized eden Summary: Before the last thread to leave a JNI critical region was able to schedule a GCLocker Initiated GC, another thread was attempting an allocation and saw that the GCLocker region was no longer active and successfully scheduled a GC. Stall allocating threads until the GCLocker Initiated GC is performed and then retry the allocation. Reviewed-by: brutisso, huntch

os_family = solaris

arch = sparc

arch_model = sparc

os_arch = solaris_sparc

os_arch_model = solaris_sparc

lib_arch = sparcv9

compiler = sparcWorks

sysdefs = -DSOLARIS -DSPARC_WORKS -DSPARC