Re: [PATCH 3/3] powerpc/mm/radix: Skip ptesync in pte update helpers

[Michael Neuling]

On Thu, 2017-02-09 at 08:28 +0530, Aneesh Kumar K.V wrote:
> We do them at the start of tlb flush, and we are sure a pte update will be
> followed by a tlbflush. Hence we can skip the ptesync in pte update helpers.
> 
> Signed-off-by: Aneesh Kumar K.V 

Tested-by: Michael Neuling 

> ---
>  arch/powerpc/include/asm/book3s/64/radix.h | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/radix.h
> b/arch/powerpc/include/asm/book3s/64/radix.h
> index fcf822d6c204..77e590c77299 100644
> --- a/arch/powerpc/include/asm/book3s/64/radix.h
> +++ b/arch/powerpc/include/asm/book3s/64/radix.h
> @@ -144,13 +144,11 @@ static inline unsigned long radix__pte_update(struct
> mm_struct *mm,
>    * new value of pte
>    */
>   new_pte = (old_pte | set) & ~clr;
> - asm volatile("ptesync" : : : "memory");
>   radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr);
>   if (new_pte)
>   __radix_pte_update(ptep, 0, new_pte);
>   } else
>   old_pte = __radix_pte_update(ptep, clr, set);
> - asm volatile("ptesync" : : : "memory");
>   if (!huge)
>   assert_pte_locked(mm, addr);
>  
> @@ -195,7 +193,6 @@ static inline void radix__ptep_set_access_flags(struct
> mm_struct *mm,
>   unsigned long old_pte, new_pte;
>  
>   old_pte = __radix_pte_update(ptep, ~0, 0);
> - asm volatile("ptesync" : : : "memory");
>   /*
>    * new value of pte
>    */

[PATCH 3/3] powerpc/mm/radix: Skip ptesync in pte update helpers

[Aneesh Kumar K.V]

We do them at the start of tlb flush, and we are sure a pte update will be
followed by a tlbflush. Hence we can skip the ptesync in pte update helpers.

Signed-off-by: Aneesh Kumar K.V 
---
 arch/powerpc/include/asm/book3s/64/radix.h | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/radix.h 
b/arch/powerpc/include/asm/book3s/64/radix.h
index fcf822d6c204..77e590c77299 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -144,13 +144,11 @@ static inline unsigned long radix__pte_update(struct 
mm_struct *mm,
 * new value of pte
 */
new_pte = (old_pte | set) & ~clr;
-   asm volatile("ptesync" : : : "memory");
radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr);
if (new_pte)
__radix_pte_update(ptep, 0, new_pte);
} else
old_pte = __radix_pte_update(ptep, clr, set);
-   asm volatile("ptesync" : : : "memory");
if (!huge)
assert_pte_locked(mm, addr);
 
@@ -195,7 +193,6 @@ static inline void radix__ptep_set_access_flags(struct 
mm_struct *mm,
unsigned long old_pte, new_pte;
 
old_pte = __radix_pte_update(ptep, ~0, 0);
-   asm volatile("ptesync" : : : "memory");
/*
 * new value of pte
 */
-- 
2.7.4