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
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
