[PATCH 3/4] powerpc/mm/radix: Use different pte update sequence for different POWER9 revs
Michael Neuling
mikey at neuling.org
Tue Sep 6 11:12:42 AEST 2016
On Wed, 2016-08-24 at 15:03 +0530, Aneesh Kumar K.V wrote:
> POWER9 DD1 requires pte to be marked invalid (V=0) before updating
> it with the new value. This makes this distinction for the different
> revisions.
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey at neuling.org>
> ---
> arch/powerpc/include/asm/book3s/32/pgtable.h | 3 +-
> arch/powerpc/include/asm/book3s/64/pgtable.h | 5 +-
> arch/powerpc/include/asm/book3s/64/radix.h | 75 ++++++++++++++++++++++------
> arch/powerpc/include/asm/nohash/32/pgtable.h | 3 +-
> arch/powerpc/include/asm/nohash/64/pgtable.h | 3 +-
> arch/powerpc/mm/pgtable-book3s64.c | 2 +-
> arch/powerpc/mm/pgtable.c | 2 +-
> 7 files changed, 71 insertions(+), 22 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
> index 38b33dcfcc9d..6b8b2d57fdc8 100644
> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
> @@ -223,7 +223,8 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
> }
>
>
> -static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
> +static inline void __ptep_set_access_flags(struct mm_struct *mm,
> + pte_t *ptep, pte_t entry)
> {
> unsigned long set = pte_val(entry) &
> (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index 263bf39ced40..8ec8be9495ba 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -565,10 +565,11 @@ static inline bool check_pte_access(unsigned long access, unsigned long ptev)
> * Generic functions with hash/radix callbacks
> */
>
> -static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
> +static inline void __ptep_set_access_flags(struct mm_struct *mm,
> + pte_t *ptep, pte_t entry)
> {
> if (radix_enabled())
> - return radix__ptep_set_access_flags(ptep, entry);
> + return radix__ptep_set_access_flags(mm, ptep, entry);
> return hash__ptep_set_access_flags(ptep, entry);
> }
>
> diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
> index a2fe8fbfbd3d..2a46dea8e1b1 100644
> --- a/arch/powerpc/include/asm/book3s/64/radix.h
> +++ b/arch/powerpc/include/asm/book3s/64/radix.h
> @@ -11,6 +11,11 @@
> #include
> #endif
>
> +#ifndef __ASSEMBLY__
> +#include
> +#include
> +#endif
> +
> /* An empty PTE can still have a R or C writeback */
> #define RADIX_PTE_NONE_MASK (_PAGE_DIRTY | _PAGE_ACCESSED)
>
> @@ -105,11 +110,8 @@
> #define RADIX_PUD_TABLE_SIZE (sizeof(pud_t) << RADIX_PUD_INDEX_SIZE)
> #define RADIX_PGD_TABLE_SIZE (sizeof(pgd_t) << RADIX_PGD_INDEX_SIZE)
>
> -static inline unsigned long radix__pte_update(struct mm_struct *mm,
> - unsigned long addr,
> - pte_t *ptep, unsigned long clr,
> - unsigned long set,
> - int huge)
> +static inline unsigned long __radix_pte_update(pte_t *ptep, unsigned long clr,
> + unsigned long set)
> {
> pte_t pte;
> unsigned long old_pte, new_pte;
> @@ -121,9 +123,39 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm,
>
> } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
>
> - /* We already do a sync in cmpxchg, is ptesync needed ?*/
> + return old_pte;
> +}
> +
> +
> +static inline unsigned long radix__pte_update(struct mm_struct *mm,
> + unsigned long addr,
> + pte_t *ptep, unsigned long clr,
> + unsigned long set,
> + int huge)
> +{
> + unsigned long old_pte;
> +
> + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
> +
> + unsigned long new_pte;
> +
> + old_pte = __radix_pte_update(ptep, ~0, 0);
> + asm volatile("ptesync" : : : "memory");
> + /*
> + * new value of pte
> + */
> + new_pte = (old_pte | set) & ~clr;
> +
> + /*
> + * For now let's do heavy pid flush
> + * radix__flush_tlb_page_psize(mm, addr, mmu_virtual_psize);
> + */
> + radix__flush_tlb_mm(mm);
> +
> + __radix_pte_update(ptep, 0, new_pte);
> + } else
> + old_pte = __radix_pte_update(ptep, clr, set);
> asm volatile("ptesync" : : : "memory");
> - /* huge pages use the old page table lock */
> if (!huge)
> assert_pte_locked(mm, addr);
>
> @@ -134,20 +166,33 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm,
> * Set the dirty and/or accessed bits atomically in a linux PTE, this
> * function doesn't need to invalidate tlb.
> */
> -static inline void radix__ptep_set_access_flags(pte_t *ptep, pte_t entry)
> +static inline void radix__ptep_set_access_flags(struct mm_struct *mm,
> + pte_t *ptep, pte_t entry)
> {
> - pte_t pte;
> - unsigned long old_pte, new_pte;
> +
> unsigned long set = pte_val(entry) & (_PAGE_DIRTY | _PAGE_ACCESSED |
> _PAGE_RW | _PAGE_EXEC);
> - do {
> - pte = READ_ONCE(*ptep);
> - old_pte = pte_val(pte);
> +
> + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
> +
> + unsigned long old_pte, new_pte;
> +
> + old_pte = __radix_pte_update(ptep, ~0, 0);
> + asm volatile("ptesync" : : : "memory");
> + /*
> + * new value of pte
> + */
> new_pte = old_pte | set;
>
> - } while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
> + /*
> + * For now let's do heavy pid flush
> + * radix__flush_tlb_page_psize(mm, addr, mmu_virtual_psize);
> + */
> + radix__flush_tlb_mm(mm);
>
> - /* We already do a sync in cmpxchg, is ptesync needed ?*/
> + __radix_pte_update(ptep, 0, new_pte);
> + } else
> + __radix_pte_update(ptep, 0, set);
> asm volatile("ptesync" : : : "memory");
> }
>
> diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
> index 780847597514..c219ef7be53b 100644
> --- a/arch/powerpc/include/asm/nohash/32/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
> @@ -267,7 +267,8 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
> }
>
>
> -static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
> +static inline void __ptep_set_access_flags(struct mm_struct *mm,
> + pte_t *ptep, pte_t entry)
> {
> unsigned long set = pte_val(entry) &
> (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
> diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
> index d4d808cf905e..653a1838469d 100644
> --- a/arch/powerpc/include/asm/nohash/64/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
> @@ -300,7 +300,8 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
> /* Set the dirty and/or accessed bits atomically in a linux PTE, this
> * function doesn't need to flush the hash entry
> */
> -static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
> +static inline void __ptep_set_access_flags(struct mm_struct *mm,
> + pte_t *ptep, pte_t entry)
> {
> unsigned long bits = pte_val(entry) &
> (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
> diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c
> index 34079302cc17..7328886bca4c 100644
> --- a/arch/powerpc/mm/pgtable-book3s64.c
> +++ b/arch/powerpc/mm/pgtable-book3s64.c
> @@ -35,7 +35,7 @@ int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
> #endif
> changed = !pmd_same(*(pmdp), entry);
> if (changed) {
> - __ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry));
> + __ptep_set_access_flags(vma->vm_mm, pmdp_ptep(pmdp), pmd_pte(entry));
> flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
> }
> return changed;
> diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
> index 0b6fb244d0a1..911fdfb63ec1 100644
> --- a/arch/powerpc/mm/pgtable.c
> +++ b/arch/powerpc/mm/pgtable.c
> @@ -224,7 +224,7 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
> if (changed) {
> if (!is_vm_hugetlb_page(vma))
> assert_pte_locked(vma->vm_mm, address);
> - __ptep_set_access_flags(ptep, entry);
> + __ptep_set_access_flags(vma->vm_mm, ptep, entry);
> flush_tlb_page(vma, address);
> }
> return changed;
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