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So we need to override mkold_clean_ptes() for arm64 to avoid it. Suggested-by: David Hildenbrand Suggested-by: Barry Song <21cnbao@gmail.com> Suggested-by: Ryan Roberts Signed-off-by: Lance Yang --- arch/arm64/include/asm/pgtable.h | 55 ++++++++++++++++++++++++++++++++ arch/arm64/mm/contpte.c | 15 +++++++++ 2 files changed, 70 insertions(+) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgta= ble.h index 9fd8613b2db2..395754638a9a 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -1223,6 +1223,34 @@ static inline void __wrprotect_ptes(struct mm_struct= *mm, unsigned long address, __ptep_set_wrprotect(mm, address, ptep); } =20 +static inline void ___ptep_mkold_clean(struct mm_struct *mm, unsigned long= addr, + pte_t *ptep, pte_t pte) +{ + pte_t old_pte; + + do { + old_pte =3D pte; + pte =3D pte_mkclean(pte_mkold(pte)); + pte_val(pte) =3D cmpxchg_relaxed(&pte_val(*ptep), + pte_val(old_pte), pte_val(pte)); + } while (pte_val(pte) !=3D pte_val(old_pte)); +} + +static inline void __ptep_mkold_clean(struct mm_struct *mm, unsigned long = addr, + pte_t *ptep) +{ + ___ptep_mkold_clean(mm, addr, ptep, __ptep_get(ptep)); +} + +static inline void __mkold_clean_ptes(struct mm_struct *mm, unsigned long = addr, + pte_t *ptep, unsigned int nr) +{ + unsigned int i; + + for (i =3D 0; i < nr; i++, addr +=3D PAGE_SIZE, ptep++) + __ptep_mkold_clean(mm, addr, ptep); +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE #define __HAVE_ARCH_PMDP_SET_WRPROTECT static inline void pmdp_set_wrprotect(struct mm_struct *mm, @@ -1379,6 +1407,8 @@ extern void contpte_wrprotect_ptes(struct mm_struct *= mm, unsigned long addr, extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t entry, int dirty); +extern void contpte_mkold_clean_ptes(struct mm_struct *mm, unsigned long a= ddr, + pte_t *ptep, unsigned int nr); =20 static __always_inline void contpte_try_fold(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte) @@ -1603,6 +1633,30 @@ static inline int ptep_set_access_flags(struct vm_ar= ea_struct *vma, return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty); } =20 +#define mkold_clean_ptes mkold_clean_ptes +static inline void mkold_clean_ptes(struct mm_struct *mm, unsigned long ad= dr, + pte_t *ptep, unsigned int nr) +{ + if (likely(nr =3D=3D 1)) { + /* + * Optimization: mkold_clean_ptes() can only be called for present + * ptes so we only need to check contig bit as condition for unfold, + * and we can remove the contig bit from the pte we read to avoid + * re-reading. This speeds up madvise(MADV_FREE) which is sensitive + * for order-0 folios. Equivalent to contpte_try_unfold(). + */ + pte_t orig_pte =3D __ptep_get(ptep); + + if (unlikely(pte_cont(orig_pte))) { + __contpte_try_unfold(mm, addr, ptep, orig_pte); + orig_pte =3D pte_mknoncont(orig_pte); + } + ___ptep_mkold_clean(mm, addr, ptep, orig_pte); + } else { + contpte_mkold_clean_ptes(mm, addr, ptep, nr); + } +} + #else /* CONFIG_ARM64_CONTPTE */ =20 #define ptep_get __ptep_get @@ -1622,6 +1676,7 @@ static inline int ptep_set_access_flags(struct vm_are= a_struct *vma, #define wrprotect_ptes __wrprotect_ptes #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS #define ptep_set_access_flags __ptep_set_access_flags +#define mkold_clean_ptes __mkold_clean_ptes =20 #endif /* CONFIG_ARM64_CONTPTE */ =20 diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index 1b64b4c3f8bf..dbff9c5e9eff 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -361,6 +361,21 @@ void contpte_wrprotect_ptes(struct mm_struct *mm, unsi= gned long addr, } EXPORT_SYMBOL_GPL(contpte_wrprotect_ptes); =20 +void contpte_mkold_clean_ptes(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned int nr) +{ + /* + * If clearing the young and dirty bits for an entire contig range, we can + * avoid unfolding. Just set old/clean and wait for the later mmu_gather + * flush to invalidate the tlb. If it's a partial range though, we need to + * unfold. + */ + + contpte_try_unfold_partial(mm, addr, ptep, nr); + __mkold_clean_ptes(mm, addr, ptep, nr); +} +EXPORT_SYMBOL_GPL(contpte_mkold_clean_ptes); + int contpte_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t entry, int dirty) --=20 2.33.1