The patch titled
Subject: mm: remove unused savedwrite infrastructure
has been added to the -mm mm-unstable branch. Its filename is
mm-remove-unused-savedwrite-infrastructure.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-unused-savedwrite-infrastructure.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: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm: remove unused savedwrite infrastructure
Date: Tue, 8 Nov 2022 18:46:51 +0100
NUMA hinting no longer uses savedwrite, let's rip it out.
... and while at it, drop __pte_write() and __pmd_write() on ppc64.
Link: https://lkml.kernel.org/r/20221108174652.198904-7-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Nadav Amit <namit@xxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 80 -----------------
arch/powerpc/kvm/book3s_hv_rm_mmu.c | 2
include/linux/pgtable.h | 24 -----
mm/debug_vm_pgtable.c | 32 ------
4 files changed, 5 insertions(+), 133 deletions(-)
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h~mm-remove-unused-savedwrite-infrastructure
+++ a/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -401,35 +401,9 @@ static inline int __ptep_test_and_clear_
#define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
#define pmdp_clear_flush_young pmdp_test_and_clear_young
-static inline int __pte_write(pte_t pte)
-{
- return !!(pte_raw(pte) & cpu_to_be64(_PAGE_WRITE));
-}
-
-#ifdef CONFIG_NUMA_BALANCING
-#define pte_savedwrite pte_savedwrite
-static inline bool pte_savedwrite(pte_t pte)
-{
- /*
- * Saved write ptes are prot none ptes that doesn't have
- * privileged bit sit. We mark prot none as one which has
- * present and pviliged bit set and RWX cleared. To mark
- * protnone which used to have _PAGE_WRITE set we clear
- * the privileged bit.
- */
- return !(pte_raw(pte) & cpu_to_be64(_PAGE_RWX | _PAGE_PRIVILEGED));
-}
-#else
-#define pte_savedwrite pte_savedwrite
-static inline bool pte_savedwrite(pte_t pte)
-{
- return false;
-}
-#endif
-
static inline int pte_write(pte_t pte)
{
- return __pte_write(pte) || pte_savedwrite(pte);
+ return !!(pte_raw(pte) & cpu_to_be64(_PAGE_WRITE));
}
static inline int pte_read(pte_t pte)
@@ -441,24 +415,16 @@ static inline int pte_read(pte_t pte)
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
- if (__pte_write(*ptep))
+ if (pte_write(*ptep))
pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 0);
- else if (unlikely(pte_savedwrite(*ptep)))
- pte_update(mm, addr, ptep, 0, _PAGE_PRIVILEGED, 0);
}
#define __HAVE_ARCH_HUGE_PTEP_SET_WRPROTECT
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- /*
- * We should not find protnone for hugetlb, but this complete the
- * interface.
- */
- if (__pte_write(*ptep))
+ if (pte_write(*ptep))
pte_update(mm, addr, ptep, _PAGE_WRITE, 0, 1);
- else if (unlikely(pte_savedwrite(*ptep)))
- pte_update(mm, addr, ptep, 0, _PAGE_PRIVILEGED, 1);
}
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
@@ -535,36 +501,6 @@ static inline int pte_protnone(pte_t pte
return (pte_raw(pte) & cpu_to_be64(_PAGE_PRESENT | _PAGE_PTE | _PAGE_RWX)) ==
cpu_to_be64(_PAGE_PRESENT | _PAGE_PTE);
}
-
-#define pte_mk_savedwrite pte_mk_savedwrite
-static inline pte_t pte_mk_savedwrite(pte_t pte)
-{
- /*
- * Used by Autonuma subsystem to preserve the write bit
- * while marking the pte PROT_NONE. Only allow this
- * on PROT_NONE pte
- */
- VM_BUG_ON((pte_raw(pte) & cpu_to_be64(_PAGE_PRESENT | _PAGE_RWX | _PAGE_PRIVILEGED)) !=
- cpu_to_be64(_PAGE_PRESENT | _PAGE_PRIVILEGED));
- return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_PRIVILEGED));
-}
-
-#define pte_clear_savedwrite pte_clear_savedwrite
-static inline pte_t pte_clear_savedwrite(pte_t pte)
-{
- /*
- * Used by KSM subsystem to make a protnone pte readonly.
- */
- VM_BUG_ON(!pte_protnone(pte));
- return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PRIVILEGED));
-}
-#else
-#define pte_clear_savedwrite pte_clear_savedwrite
-static inline pte_t pte_clear_savedwrite(pte_t pte)
-{
- VM_WARN_ON(1);
- return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_WRITE));
-}
#endif /* CONFIG_NUMA_BALANCING */
static inline bool pte_hw_valid(pte_t pte)
@@ -641,8 +577,6 @@ static inline unsigned long pte_pfn(pte_
/* Generic modifiers for PTE bits */
static inline pte_t pte_wrprotect(pte_t pte)
{
- if (unlikely(pte_savedwrite(pte)))
- return pte_clear_savedwrite(pte);
return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_WRITE));
}
@@ -1139,8 +1073,6 @@ static inline pte_t *pmdp_ptep(pmd_t *pm
#define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd)))
#define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
#define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd)))
-#define pmd_mk_savedwrite(pmd) pte_pmd(pte_mk_savedwrite(pmd_pte(pmd)))
-#define pmd_clear_savedwrite(pmd) pte_pmd(pte_clear_savedwrite(pmd_pte(pmd)))
#ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
#define pmd_soft_dirty(pmd) pte_soft_dirty(pmd_pte(pmd))
@@ -1162,8 +1094,6 @@ static inline int pmd_protnone(pmd_t pmd
#endif /* CONFIG_NUMA_BALANCING */
#define pmd_write(pmd) pte_write(pmd_pte(pmd))
-#define __pmd_write(pmd) __pte_write(pmd_pte(pmd))
-#define pmd_savedwrite(pmd) pte_savedwrite(pmd_pte(pmd))
#define pmd_access_permitted pmd_access_permitted
static inline bool pmd_access_permitted(pmd_t pmd, bool write)
@@ -1241,10 +1171,8 @@ static inline int __pmdp_test_and_clear_
static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp)
{
- if (__pmd_write((*pmdp)))
+ if (pmd_write(*pmdp))
pmd_hugepage_update(mm, addr, pmdp, _PAGE_WRITE, 0);
- else if (unlikely(pmd_savedwrite(*pmdp)))
- pmd_hugepage_update(mm, addr, pmdp, 0, _PAGE_PRIVILEGED);
}
/*
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c~mm-remove-unused-savedwrite-infrastructure
+++ a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -265,7 +265,7 @@ long kvmppc_do_h_enter(struct kvm *kvm,
}
pte = kvmppc_read_update_linux_pte(ptep, writing);
if (pte_present(pte) && !pte_protnone(pte)) {
- if (writing && !__pte_write(pte))
+ if (writing && !pte_write(pte))
/* make the actual HPTE be read-only */
ptel = hpte_make_readonly(ptel);
is_ci = pte_ci(pte);
--- a/include/linux/pgtable.h~mm-remove-unused-savedwrite-infrastructure
+++ a/include/linux/pgtable.h
@@ -485,30 +485,6 @@ static inline pte_t pte_sw_mkyoung(pte_t
#define pte_sw_mkyoung pte_sw_mkyoung
#endif
-#ifndef pte_savedwrite
-#define pte_savedwrite pte_write
-#endif
-
-#ifndef pte_mk_savedwrite
-#define pte_mk_savedwrite pte_mkwrite
-#endif
-
-#ifndef pte_clear_savedwrite
-#define pte_clear_savedwrite pte_wrprotect
-#endif
-
-#ifndef pmd_savedwrite
-#define pmd_savedwrite pmd_write
-#endif
-
-#ifndef pmd_mk_savedwrite
-#define pmd_mk_savedwrite pmd_mkwrite
-#endif
-
-#ifndef pmd_clear_savedwrite
-#define pmd_clear_savedwrite pmd_wrprotect
-#endif
-
#ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline void pmdp_set_wrprotect(struct mm_struct *mm,
--- a/mm/debug_vm_pgtable.c~mm-remove-unused-savedwrite-infrastructure
+++ a/mm/debug_vm_pgtable.c
@@ -171,18 +171,6 @@ static void __init pte_advanced_tests(st
ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1);
}
-static void __init pte_savedwrite_tests(struct pgtable_debug_args *args)
-{
- pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot_none);
-
- if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
- return;
-
- pr_debug("Validating PTE saved write\n");
- WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte))));
- WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte))));
-}
-
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx)
{
@@ -302,22 +290,6 @@ static void __init pmd_leaf_tests(struct
WARN_ON(!pmd_leaf(pmd));
}
-static void __init pmd_savedwrite_tests(struct pgtable_debug_args *args)
-{
- pmd_t pmd;
-
- if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
- return;
-
- if (!has_transparent_hugepage())
- return;
-
- pr_debug("Validating PMD saved write\n");
- pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot_none);
- WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
- WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
-}
-
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx)
{
@@ -451,7 +423,6 @@ static void __init pmd_advanced_tests(st
static void __init pud_advanced_tests(struct pgtable_debug_args *args) { }
static void __init pmd_leaf_tests(struct pgtable_debug_args *args) { }
static void __init pud_leaf_tests(struct pgtable_debug_args *args) { }
-static void __init pmd_savedwrite_tests(struct pgtable_debug_args *args) { }
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
@@ -1288,9 +1259,6 @@ static int __init debug_vm_pgtable(void)
pmd_leaf_tests(&args);
pud_leaf_tests(&args);
- pte_savedwrite_tests(&args);
- pmd_savedwrite_tests(&args);
-
pte_special_tests(&args);
pte_protnone_tests(&args);
pmd_protnone_tests(&args);
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
selftests-vm-anon_cow-test-cow-handling-of-anonymous-memory.patch
selftests-vm-anon_cow-test-cow-handling-of-anonymous-memory-fix.patch
selftests-vm-factor-out-pagemap_is_populated-into-vm_util.patch
selftests-vm-anon_cow-thp-tests.patch
selftests-vm-anon_cow-hugetlb-tests.patch
selftests-vm-anon_cow-add-liburing-test-cases.patch
selftests-vm-anon_cow-add-liburing-test-cases-fix.patch
mm-gup_test-start-stop-read-functionality-for-pin-longterm-test.patch
mm-gup_test-start-stop-read-functionality-for-pin-longterm-test-fix.patch
selftests-vm-anon_cow-add-r-o-longterm-tests-via-gup_test.patch
selftests-vm-add-ksm-unmerge-tests.patch
mm-pagewalk-dont-trigger-test_walk-in-walk_page_vma.patch
selftests-vm-add-test-to-measure-madv_unmergeable-performance.patch
mm-ksm-simplify-break_ksm-to-not-rely-on-vm_fault_write.patch
mm-remove-vm_fault_write.patch
mm-ksm-fix-ksm-cow-breaking-with-userfaultfd-wp-via-fault_flag_unshare.patch
mm-pagewalk-add-walk_page_range_vma.patch
mm-ksm-convert-break_ksm-to-use-walk_page_range_vma.patch
mm-gup-remove-foll_migration.patch
mm-mprotect-minor-can_change_pte_writable-cleanups.patch
mm-huge_memory-try-avoiding-write-faults-when-changing-pmd-protection.patch
mm-mprotect-factor-out-check-whether-manual-pte-write-upgrades-are-required.patch
mm-autonuma-use-can_change_ptepmd_writable-to-replace-savedwrite.patch
mm-remove-unused-savedwrite-infrastructure.patch
selftests-vm-anon_cow-add-mprotect-optimization-tests.patch
