This patch series enables HugeTLB migration support for all supported huge page sizes at all levels including contiguous bit implementation. Following HugeTLB migration support matrix has been enabled with this patch series. All permutations have been tested except for the 16GB. CONT PTE PMD CONT PMD PUD -------- --- -------- --- 4K: 64K 2M 32M 1G 16K: 2M 32M 1G 64K: 2M 512M 16G First the series adds migration support for PUD based huge pages. It then adds a platform specific hook to query an architecture if a given huge page size is supported for migration while also providing a default fallback option preserving the existing semantics which just checks for (PMD|PUD|PGDIR)_SHIFT macros. The last two patches enables HugeTLB migration on arm64 and subscribe to this new platform specific hook by defining an override. The second patch differentiates between movability and migratability aspects of huge pages and implements hugepage_movable_supported() which can then be used during allocation to decide whether to place the huge page in movable zone or not. This is just a resend for the previous version (V3) after the rebase on current mainline kernel. Also added all the tags previous version had received. Changes in V3: - Re-ordered patches 1 and 2 per Michal - s/Movability/Migratability/ in unmap_and_move_huge_page() per Naoya Changes in V2: (https://lkml.org/lkml/2018/10/12/190) - Added a new patch which differentiates migratability and movability of huge pages and implements hugepage_movable_supported() function as suggested by Michal Hocko. Anshuman Khandual (5): mm/hugetlb: Distinguish between migratability and movability mm/hugetlb: Enable PUD level huge page migration mm/hugetlb: Enable arch specific huge page size support for migration arm64/mm: Enable HugeTLB migration arm64/mm: Enable HugeTLB migration for contiguous bit HugeTLB pages arch/arm64/Kconfig | 4 ++++ arch/arm64/include/asm/hugetlb.h | 5 +++++ arch/arm64/mm/hugetlbpage.c | 20 +++++++++++++++++ include/linux/hugetlb.h | 48 +++++++++++++++++++++++++++++++++++++--- mm/hugetlb.c | 2 +- mm/migrate.c | 2 +- 6 files changed, 76 insertions(+), 5 deletions(-) -- 2.7.4