[PATCH v10 6/9] powerpc/mm: Remove flush_all_mm, local_flush_all_mm

[Christophe Leroy]

Le 09/11/2022 à 05:51, Benjamin Gray a écrit :
> These functions were introduced for "cxl: Enable global TLBIs for cxl
> contexts" [1], which ended up using them for Radix only. They were never
> implemented on Hash (and creating an implementation appears to be
> difficult), so nothing can actually rely on them.
> 
> They behave differently to the existing surrounding functions too, in
> that they actually need to do something on Hash. The other functions
> are primarily for use in generic code that expects their definitions,
> but Hash updates the TLB during PTE updates.
> 
> After replacing the only usage with the Radix specific version, there
> are no more users of these functions, and given they are not implemented
> anyway it is safe to delete them.
> 
> [1]: https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20170903181513.29635-1-fbarrat@linux.vnet.ibm.com/
> 
> Signed-off-by: Benjamin Gray <bgray at linux.ibm.com>

Good cleanup


Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>



> ---
> v10:	* New in v10 to remove the hash__ set of functions
> ---
>   .../include/asm/book3s/64/tlbflush-hash.h     | 22 -------------------
>   arch/powerpc/include/asm/book3s/64/tlbflush.h | 15 -------------
>   2 files changed, 37 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h b/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h
> index 38d31c2489d3..cdbb1a04bb52 100644
> --- a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h
> +++ b/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h
> @@ -59,28 +59,6 @@ void flush_hash_range(unsigned long number, int local);
>   void flush_hash_hugepage(unsigned long vsid, unsigned long addr, pmd_t *pmdp,
>   			 unsigned int psize, int ssize, unsigned long flags);
>   
> -static inline void hash__local_flush_all_mm(struct mm_struct *mm)
> -{
> -	/*
> -	 * There's no Page Walk Cache for hash, so what is needed is
> -	 * the same as flush_tlb_mm(), which doesn't really make sense
> -	 * with hash. So the only thing we could do is flush the
> -	 * entire LPID! Punt for now, as it's not being used.
> -	 */
> -	WARN_ON_ONCE(1);
> -}
> -
> -static inline void hash__flush_all_mm(struct mm_struct *mm)
> -{
> -	/*
> -	 * There's no Page Walk Cache for hash, so what is needed is
> -	 * the same as flush_tlb_mm(), which doesn't really make sense
> -	 * with hash. So the only thing we could do is flush the
> -	 * entire LPID! Punt for now, as it's not being used.
> -	 */
> -	WARN_ON_ONCE(1);
> -}
> -
>   struct mmu_gather;
>   void hash__tlb_flush(struct mmu_gather *tlb);
>   
> diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush.h b/arch/powerpc/include/asm/book3s/64/tlbflush.h
> index 2254a40f0564..c56a0aee8124 100644
> --- a/arch/powerpc/include/asm/book3s/64/tlbflush.h
> +++ b/arch/powerpc/include/asm/book3s/64/tlbflush.h
> @@ -86,13 +86,6 @@ static inline void local_flush_tlb_page(struct vm_area_struct *vma,
>   		radix__local_flush_tlb_page(vma, vmaddr);
>   }
>   
> -static inline void local_flush_all_mm(struct mm_struct *mm)
> -{
> -	if (radix_enabled())
> -		return radix__local_flush_all_mm(mm);
> -	return hash__local_flush_all_mm(mm);
> -}
> -
>   static inline void tlb_flush(struct mmu_gather *tlb)
>   {
>   	if (radix_enabled())
> @@ -112,17 +105,9 @@ static inline void flush_tlb_page(struct vm_area_struct *vma,
>   	if (radix_enabled())
>   		radix__flush_tlb_page(vma, vmaddr);
>   }
> -
> -static inline void flush_all_mm(struct mm_struct *mm)
> -{
> -	if (radix_enabled())
> -		return radix__flush_all_mm(mm);
> -	return hash__flush_all_mm(mm);
> -}
>   #else
>   #define flush_tlb_mm(mm)		local_flush_tlb_mm(mm)
>   #define flush_tlb_page(vma, addr)	local_flush_tlb_page(vma, addr)
> -#define flush_all_mm(mm)		local_flush_all_mm(mm)
>   #endif /* CONFIG_SMP */
>   
>   #define flush_tlb_fix_spurious_fault flush_tlb_fix_spurious_fault