Introduce two more sub-options for PGTABLE_HAS_HUGE_LEAVES: - PGTABLE_HAS_PMD_LEAVES: set when there can be PMD mappings - PGTABLE_HAS_PUD_LEAVES: set when there can be PUD mappings It will help to identify whether the current build may only want PMD helpers but not PUD ones, as these sub-options will also check against the arch support over HAVE_ARCH_TRANSPARENT_HUGEPAGE[_PUD]. Note that having them depend on HAVE_ARCH_TRANSPARENT_HUGEPAGE[_PUD] is still some intermediate step. The best way is to have an option say "whether arch XXX supports PMD/PUD mappings" and so on. However let's leave that for later as that's the easy part. So far, we use these options to stably detect per-arch huge mapping support. Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> --- include/linux/huge_mm.h | 10 +++++++--- mm/Kconfig | 6 ++++++ 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 711632df7edf..37482c8445d1 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -96,14 +96,18 @@ extern struct kobj_attribute thpsize_shmem_enabled_attr; #define thp_vma_allowable_order(vma, vm_flags, tva_flags, order) \ (!!thp_vma_allowable_orders(vma, vm_flags, tva_flags, BIT(order))) -#ifdef CONFIG_PGTABLE_HAS_HUGE_LEAVES -#define HPAGE_PMD_SHIFT PMD_SHIFT +#ifdef CONFIG_PGTABLE_HAS_PUD_LEAVES #define HPAGE_PUD_SHIFT PUD_SHIFT #else -#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) #define HPAGE_PUD_SHIFT ({ BUILD_BUG(); 0; }) #endif +#ifdef CONFIG_PGTABLE_HAS_PMD_LEAVES +#define HPAGE_PMD_SHIFT PMD_SHIFT +#else +#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) +#endif + #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) #define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) diff --git a/mm/Kconfig b/mm/Kconfig index 60796402850e..2dbdc088dee8 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -860,6 +860,12 @@ endif # TRANSPARENT_HUGEPAGE config PGTABLE_HAS_HUGE_LEAVES def_bool TRANSPARENT_HUGEPAGE || HUGETLB_PAGE +config PGTABLE_HAS_PMD_LEAVES + def_bool HAVE_ARCH_TRANSPARENT_HUGEPAGE && PGTABLE_HAS_HUGE_LEAVES + +config PGTABLE_HAS_PUD_LEAVES + def_bool HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD && PGTABLE_HAS_HUGE_LEAVES + # # UP and nommu archs use km based percpu allocator # -- 2.45.0