Arm disabled hugetlb vmemmap optimization [1] because hugetlb vmemmap optimization includes an update of both the permissions (writeable to read-only) and the output address (pfn) of the vmemmap ptes. That is not supported without unmapping of pte(marking it invalid) by some architectures.
With DAX vmemmap optimization we don't require such pte updates and architectures can enable DAX vmemmap optimization while having hugetlb vmemmap optimization disabled. Hence split DAX optimization support into a different config. s390, loongarch and riscv don't have devdax support. So the DAX config is not enabled for them. With this change, arm64 should be able to select DAX optimization [1] commit 060a2c92d1b6 ("arm64: mm: hugetlb: Disable HUGETLB_PAGE_OPTIMIZE_VMEMMAP") Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com> --- arch/loongarch/Kconfig | 2 +- arch/riscv/Kconfig | 2 +- arch/s390/Kconfig | 2 +- arch/x86/Kconfig | 3 ++- fs/Kconfig | 2 +- include/linux/mm.h | 2 +- mm/Kconfig | 5 ++++- 7 files changed, 11 insertions(+), 7 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index e55511af4c77..537ca2a4005a 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -59,7 +59,7 @@ config LOONGARCH select ARCH_USE_QUEUED_SPINLOCKS select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT select ARCH_WANT_LD_ORPHAN_WARN - select ARCH_WANT_OPTIMIZE_VMEMMAP + select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP select ARCH_WANTS_NO_INSTR select BUILDTIME_TABLE_SORT select COMMON_CLK diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4c07b9189c86..6943d34c1ec1 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -53,7 +53,7 @@ config RISCV select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT select ARCH_WANT_HUGE_PMD_SHARE if 64BIT select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL - select ARCH_WANT_OPTIMIZE_VMEMMAP + select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU select BUILDTIME_TABLE_SORT if MMU diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 290b6f93b816..8ff6d1c21e38 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -127,7 +127,7 @@ config S390 select ARCH_WANTS_NO_INSTR select ARCH_WANT_DEFAULT_BPF_JIT select ARCH_WANT_IPC_PARSE_VERSION - select ARCH_WANT_OPTIMIZE_VMEMMAP + select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP select BUILDTIME_TABLE_SORT select CLONE_BACKWARDS2 select DMA_OPS if PCI diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7422db409770..78224aa76409 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -128,7 +128,8 @@ config X86 select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE select ARCH_WANT_LD_ORPHAN_WARN - select ARCH_WANT_OPTIMIZE_VMEMMAP if X86_64 + select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP if X86_64 + select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP if X86_64 select ARCH_WANTS_THP_SWAP if X86_64 select ARCH_HAS_PARANOID_L1D_FLUSH select BUILDTIME_TABLE_SORT diff --git a/fs/Kconfig b/fs/Kconfig index 19975b104bc3..f3be721bab6d 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -254,7 +254,7 @@ config HUGETLB_PAGE config HUGETLB_PAGE_OPTIMIZE_VMEMMAP def_bool HUGETLB_PAGE - depends on ARCH_WANT_OPTIMIZE_VMEMMAP + depends on ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP depends on SPARSEMEM_VMEMMAP config HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON diff --git a/include/linux/mm.h b/include/linux/mm.h index fe6741539740..f8899bda941a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3650,7 +3650,7 @@ void vmemmap_free(unsigned long start, unsigned long end, #endif #define VMEMMAP_RESERVE_NR 2 -#ifdef CONFIG_ARCH_WANT_OPTIMIZE_VMEMMAP +#ifdef CONFIG_ARCH_WANT_OPTIMIZE_DAX_VMEMMAP static inline bool __vmemmap_can_optimize(struct vmem_altmap *altmap, struct dev_pagemap *pgmap) { diff --git a/mm/Kconfig b/mm/Kconfig index da681dda8af1..5fe49c030961 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -486,7 +486,10 @@ config SPARSEMEM_VMEMMAP # Select this config option from the architecture Kconfig, if it is preferred # to enable the feature of HugeTLB/dev_dax vmemmap optimization. # -config ARCH_WANT_OPTIMIZE_VMEMMAP +config ARCH_WANT_OPTIMIZE_DAX_VMEMMAP + bool + +config ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP bool config HAVE_MEMBLOCK_PHYS_MAP -- 2.41.0