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We no longer need to > think about whether the inode is hugetlb or not before doing the lookup > and scaling the byte offset differently. I 'think' this was the primary motivation for this patch. Recent discussions about HGM always came back to hugetlb special case code in the core mm. HGM would add a little more, and most people thought there was too much already. Most everyone in those discussions agreed there should be some effort to unify hugetlb and core mm code as much as possible to reduce these special cases. This is one step in that direction. As a hugetlb maintainer, I don't like any decrease in performance even if it is not readily observable. However, as a member of the mm community I like the fact that there is less special case hugetlb code. Overall, I consider this a win. -- Mike Kravetz