From: Zi Yan <zi.yan@xxxxxxxxxxxxxx> Hi all, THP migration is only enabled on x86_64 with a special ARCH_ENABLE_THP_MIGRATION macro. This patchset enables THP migration for all architectures that uses transparent hugepage, so that special macro can be dropped. Instead, THP migration is enabled/disabled via /sys/kernel/mm/transparent_hugepage/enable_thp_migration. I grepped for TRANSPARENT_HUGEPAGE in arch folder and got 9 architectures that are supporting transparent hugepage. I mechanically add __pmd_to_swp_entry() and __swp_entry_to_pmd() based on existing __pte_to_swp_entry() and __swp_entry_to_pte() for all these architectures, except tile which is going to be dropped. I have successfully compiled all these architectures, but have NOT tested them due to lack of real hardware. I appreciate your help, if the maintainers of these architectures can do a quick test with the code from https://github.com/x-y-z/thp-migration-bench . Please apply patch 9 as well to enable THP migration. By enabling THP migration, migrating a 2MB THP on x86_64 machines takes only 1/3 time of migrating equivalent 512 4KB pages. Hi Naoya, I also add soft dirty support for powerpc and s390. It would be great if you can take a look at patch 6 & 7. Feel free to give comments. Thanks. Cc: linux-mm@xxxxxxxxx Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx> Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Christoffer Dall <christoffer.dall@xxxxxxxxxx> Cc: Marc Zyngier <marc.zyngier@xxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Steve Capper <steve.capper@xxxxxxx> Cc: Kristina Martsenko <kristina.martsenko@xxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: x86@xxxxxxxxxx Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: James Hogan <jhogan@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxx Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx> Cc: Ram Pai <linuxram@xxxxxxxxxx> Cc: Balbir Singh <bsingharora@xxxxxxxxx> Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx> Cc: linux-s390@xxxxxxxxxxxxxxx Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: sparclinux@xxxxxxxxxxxxxxx Cc: "Huang, Ying" <ying.huang@xxxxxxxxx> Zi Yan (9): arc: mm: migrate: add pmd swap entry to support thp migration. arm: mm: migrate: add pmd swap entry to support thp migration. arm64: mm: migrate: add pmd swap entry to support thp migration. i386: mm: migrate: add pmd swap entry to support thp migration. mips: mm: migrate: add pmd swap entry to support thp migration. powerpc: mm: migrate: add pmd swap entry to support thp migration. s390: mm: migrate: add pmd swap entry to support thp migration. sparc: mm: migrate: add pmd swap entry to support thp migration. mm: migrate: enable thp migration for all possible architectures. arch/arc/include/asm/pgtable.h | 2 ++ arch/arm/include/asm/pgtable.h | 2 ++ arch/arm64/include/asm/pgtable.h | 2 ++ arch/mips/include/asm/pgtable-64.h | 2 ++ arch/powerpc/include/asm/book3s/32/pgtable.h | 2 ++ arch/powerpc/include/asm/book3s/64/pgtable.h | 17 ++++++++++++ arch/powerpc/include/asm/nohash/32/pgtable.h | 2 ++ arch/powerpc/include/asm/nohash/64/pgtable.h | 2 ++ arch/s390/include/asm/pgtable.h | 5 ++++ arch/sparc/include/asm/pgtable_32.h | 2 ++ arch/sparc/include/asm/pgtable_64.h | 2 ++ arch/x86/Kconfig | 4 --- arch/x86/include/asm/pgtable-2level.h | 2 ++ arch/x86/include/asm/pgtable-3level.h | 2 ++ arch/x86/include/asm/pgtable.h | 2 -- fs/proc/task_mmu.c | 2 -- include/asm-generic/pgtable.h | 21 ++------------- include/linux/huge_mm.h | 9 +++---- include/linux/swapops.h | 4 +-- mm/Kconfig | 3 --- mm/huge_memory.c | 27 +++++++++++++------- mm/migrate.c | 6 ++--- mm/rmap.c | 5 ++-- 23 files changed, 73 insertions(+), 54 deletions(-) -- 2.17.0