Suppose a hugepage-aligned mmap(MAP_ANONYMOUS) mapping has been madvise()d HUGEPAGE. If a subeqeuent call to mremap() grows the mapping and has to move the mapping, the hugepage-alignment is not preserved in the choice of new address (in 3.7.2).
I can workaround this by doing a 1-hugepage-oversized remap to find a new aligned address and then size it back down MREMAP_FIXED, but that's probably a lot of frags to 4k pages and back that aren't necessary. Should it not be the case that mremap(MAYMOVE) on something advised hugepage ALWAYS chooses a hugepage-aligned address? This would be handy when doing the initial allocation too: mmap, madvise, mremap (to the same size) to get alignment. Cheers, -mcq -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
