The patch titled
Subject: mm/vmemmap optimization: split hugetlb and devdax vmemmap optimization
has been added to the -mm mm-unstable branch. Its filename is
mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx>
Subject: mm/vmemmap optimization: split hugetlb and devdax vmemmap optimization
Date: Tue, 25 Jul 2023 00:37:53 +0530
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")
Link: https://lkml.kernel.org/r/20230724190759.483013-8-aneesh.kumar@xxxxxxxxxxxxx
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Joao Martins <joao.m.martins@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
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(-)
--- a/arch/loongarch/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
--- a/arch/riscv/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
--- a/arch/s390/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
--- a/arch/x86/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
--- a/fs/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
--- a/include/linux/mm.h~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/include/linux/mm.h
@@ -3666,7 +3666,7 @@ void vmemmap_free(unsigned long start, u
#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)
{
--- a/mm/Kconfig~mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization
+++ a/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
_
Patches currently in -mm which might be from aneesh.kumar@xxxxxxxxxxxxx are
mm-hugepage-pud-allow-arch-specific-helper-function-to-check-huge-page-pud-support.patch
mm-change-pudp_huge_get_and_clear_full-take-vm_area_struct-as-arg.patch
mm-vmemmap-improve-vmemmap_can_optimize-and-allow-architectures-to-override.patch
mm-vmemmap-allow-architectures-to-override-how-vmemmap-optimization-works.patch
mm-add-pud_same-similar-to-__have_arch_p4d_same.patch
mm-huge-pud-use-transparent-huge-pud-helpers-only-with-config_transparent_hugepage.patch
mm-vmemmap-optimization-split-hugetlb-and-devdax-vmemmap-optimization.patch
powerpc-mm-trace-convert-trace-event-to-trace-event-class.patch
powerpc-book3s64-mm-enable-transparent-pud-hugepage.patch
powerpc-book3s64-vmemmap-switch-radix-to-use-a-different-vmemmap-handling-function.patch
powerpc-book3s64-radix-add-support-for-vmemmap-optimization-for-radix.patch
powerpc-book3s64-radix-remove-mmu_vmemmap_psize.patch
powerpc-book3s64-radix-add-debug-message-to-give-more-details-of-vmemmap-allocation.patch
