The patch titled
Subject: arm64/mm: ptep_get_and_clear(): new layer to manage contig bit
has been added to the -mm mm-unstable branch. Its filename is
arm64-mm-ptep_get_and_clear-new-layer-to-manage-contig-bit.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arm64-mm-ptep_get_and_clear-new-layer-to-manage-contig-bit.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Ryan Roberts <ryan.roberts@xxxxxxx>
Subject: arm64/mm: ptep_get_and_clear(): new layer to manage contig bit
Date: Mon, 18 Dec 2023 10:50:51 +0000
Create a new layer for the in-table PTE manipulation APIs. For now, The
existing API is prefixed with double underscore to become the arch-private
API and the public API is just a simple wrapper that calls the private
API.
The public API implementation will subsequently be used to transparently
manipulate the contiguous bit where appropriate. But since there are
already some contig-aware users (e.g. hugetlb, kernel mapper), we must
first ensure those users use the private API directly so that the future
contig-bit manipulations in the public API do not interfere with those
existing uses.
Link: https://lkml.kernel.org/r/20231218105100.172635-8-ryan.roberts@xxxxxxx
Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Tested-by: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Barry Song <21cnbao@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Oliver Upton <oliver.upton@xxxxxxxxx>
Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Zenghui Yu <yuzenghui@xxxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/arm64/include/asm/pgtable.h | 5 +++--
arch/arm64/mm/hugetlbpage.c | 6 +++---
2 files changed, 6 insertions(+), 5 deletions(-)
--- a/arch/arm64/include/asm/pgtable.h~arm64-mm-ptep_get_and_clear-new-layer-to-manage-contig-bit
+++ a/arch/arm64/include/asm/pgtable.h
@@ -941,8 +941,7 @@ static inline int pmdp_test_and_clear_yo
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
-static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
+static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
unsigned long address, pte_t *ptep)
{
pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
@@ -1122,6 +1121,8 @@ extern void ptep_modify_prot_commit(stru
#define set_pte __set_pte
#define set_ptes __set_ptes
#define pte_clear __pte_clear
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
+#define ptep_get_and_clear __ptep_get_and_clear
#endif /* !__ASSEMBLY__ */
--- a/arch/arm64/mm/hugetlbpage.c~arm64-mm-ptep_get_and_clear-new-layer-to-manage-contig-bit
+++ a/arch/arm64/mm/hugetlbpage.c
@@ -188,7 +188,7 @@ static pte_t get_clear_contig(struct mm_
unsigned long i;
for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
- pte_t pte = ptep_get_and_clear(mm, addr, ptep);
+ pte_t pte = __ptep_get_and_clear(mm, addr, ptep);
/*
* If HW_AFDBM is enabled, then the HW could turn on
@@ -236,7 +236,7 @@ static void clear_flush(struct mm_struct
unsigned long i, saddr = addr;
for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- ptep_clear(mm, addr, ptep);
+ __ptep_get_and_clear(mm, addr, ptep);
flush_tlb_range(&vma, saddr, addr);
}
@@ -411,7 +411,7 @@ pte_t huge_ptep_get_and_clear(struct mm_
pte_t orig_pte = ptep_get(ptep);
if (!pte_cont(orig_pte))
- return ptep_get_and_clear(mm, addr, ptep);
+ return __ptep_get_and_clear(mm, addr, ptep);
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
_
Patches currently in -mm which might be from ryan.roberts@xxxxxxx are
mm-allow-deferred-splitting-of-arbitrary-anon-large-folios.patch
mm-non-pmd-mappable-large-folios-for-folio_add_new_anon_rmap.patch
mm-thp-introduce-multi-size-thp-sysfs-interface.patch
mm-thp-introduce-multi-size-thp-sysfs-interface-fix.patch
mm-thp-support-allocation-of-anonymous-multi-size-thp.patch
mm-thp-support-allocation-of-anonymous-multi-size-thp-fix.patch
selftests-mm-kugepaged-restore-thp-settings-at-exit.patch
selftests-mm-factor-out-thp-settings-management.patch
selftests-mm-support-multi-size-thp-interface-in-thp_settings.patch
selftests-mm-khugepaged-enlighten-for-multi-size-thp.patch
selftests-mm-cow-generalize-do_run_with_thp-helper.patch
selftests-mm-cow-add-tests-for-anonymous-multi-size-thp.patch
mm-thp-batch-collapse-pmd-with-set_ptes.patch
mm-batch-copy-pte-ranges-during-fork.patch
mm-batch-clear-pte-ranges-during-zap_pte_range.patch
arm64-mm-set_pte-new-layer-to-manage-contig-bit.patch
arm64-mm-set_ptes-set_pte_at-new-layer-to-manage-contig-bit.patch
arm64-mm-pte_clear-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_get_and_clear-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_test_and_clear_young-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_clear_flush_young-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_set_wrprotect-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_set_access_flags-new-layer-to-manage-contig-bit.patch
arm64-mm-ptep_get-new-layer-to-manage-contig-bit.patch
arm64-mm-split-__flush_tlb_range-to-elide-trailing-dsb.patch
arm64-mm-wire-up-pte_cont-for-user-mappings.patch
arm64-mm-implement-new-helpers-to-optimize-fork.patch
arm64-mm-implement-clear_ptes-to-optimize-exit-munmap-dontneed.patch
selftests-mm-log-run_vmtestssh-results-in-tap-format.patch
