Re: [PATCH V3 0/5] arm64/mm: Enable HugeTLB migration

From: Anshuman Khandual
Date: Fri Nov 23 2018 - 10:08:33 EST




On 10/23/2018 06:31 PM, Anshuman Khandual wrote:
> 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.
>
> 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

Hello Andrew,

This patch series has been reviewed and acked both for it's core MM and
arm64 changes. Could you please consider this series. Thank you.

- Anshuman