@@ -1589,6 +1589,10 @@ config ARCH_ENABLE_HUGEPAGE_MIGRATION
def_bool y
depends on HUGETLB_PAGE && MIGRATION
+config ARCH_ENABLE_THP_MIGRATION
+ def_bool y
+ depends on TRANSPARENT_HUGEPAGE
+
menu "Power management options"
source "kernel/power/Kconfig"
@@ -851,6 +851,11 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
+#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
+#define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
+#define __swp_entry_to_pmd(swp) __pmd((swp).val)
+#endif
+
/*
* Ensure that there are not more swap files than can be encoded in the kernel
* PTEs.
In certain page migration situations a THP page can be migrated without being split into it's constituent normal pages. This not only saves time required to split the THP page later to be put back when required but also saves an wider address range translation from the existing huge TLB entry reducing future page fault costs. The previous patch changed the THP helper functions which now complies with the generic MM semantics clearing the path for THP migration support. Hence just enable it. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Suzuki Poulose <suzuki.poulose@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> --- arch/arm64/Kconfig | 4 ++++ arch/arm64/include/asm/pgtable.h | 5 +++++ 2 files changed, 9 insertions(+)