RFR (XS): 8054808: Bitmap verification sometimes fails after Full GC aborts concurrent mark
thomas.schatzl at oracle.com
Wed Aug 27 13:24:08 UTC 2014
can I have reviews for the following fix that fixes next bitmap
verification after a full gc aborted concurrent mark?
The original code to verify whether a region's next bitmap contained a
mark or not was racy: in CheckBitmapClearHRClosure::doHeapRegion the
result whether the bitmap had marks was:
return _bitmap->getNextMarkedWordAddress(r->bottom(), r->end()) !=
The problem is that concurrent humongous object allocation changes
HeapRegion::_end, and if that occurs between the initial evaluation for
the method call and the comparison, the checking will fail.
Inspecting generated code, test case in the CR, jprt
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