Re: [PATCH v4 07/12] mm: enable MMU_GATHER_RCU_TABLE_FREE for m68k-coldfire

[Greg Ungerer]

Hi Lorenzo,

On 23/9/26 01:35, Lorenzo Stoakes (ARM) wrote:
> Similar to sun3, the coldfire variant of m68k uses 2-level page tables.
> 
> Update its __pte_free_tlb() function to use tlb_remove_ptdesc() in order
> that, with CONFIG_MMU_GATHER_RCU_TABLE_FREE, page tables are freed under
> RCU.
> 
> The page tables occupy a page each and have no odd semantics, so this
> change suffices to allow enabling of CONFIG_MMU_GATHER_RCU_TABLE_FREE for
> m68k-coldfire, so do so.
> 
> This forms part of an overall effort to switch every architecture to this
> mode.
> 
> Acked-by: Kiryl Shutsemau (Meta) <kas@xxxxxxxxxx>
> Signed-off-by: Lorenzo Stoakes (ARM) <ljs@xxxxxxxxxx>

Looks good to me for ColdFire, so:

Acked-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>

Tested and run with no issues I could see on a M5475 ColdFire system, so:

Tested-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>

Regards
Greg



> ---
>  arch/m68k/Kconfig                   | 2 +-
>  arch/m68k/include/asm/mcf_pgalloc.h | 5 +----
>  2 files changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
> index e29610fd1240..6b8ec67c86fd 100644
> --- a/arch/m68k/Kconfig
> +++ b/arch/m68k/Kconfig
> @@ -36,7 +36,7 @@ config M68K
>  	select HAVE_MOD_ARCH_SPECIFIC
>  	select HAVE_UID16
>  	select MMU_GATHER_NO_RANGE if MMU
> -	select MMU_GATHER_RCU_TABLE_FREE if MMU && SUN3
> +	select MMU_GATHER_RCU_TABLE_FREE if MMU && (SUN3 || COLDFIRE)
>  	select MODULES_USE_ELF_REL
>  	select MODULES_USE_ELF_RELA
>  	select NO_DMA if !MMU && !COLDFIRE
> diff --git a/arch/m68k/include/asm/mcf_pgalloc.h b/arch/m68k/include/asm/mcf_pgalloc.h
> index fc5454d37da3..b53ff0950db2 100644
> --- a/arch/m68k/include/asm/mcf_pgalloc.h
> +++ b/arch/m68k/include/asm/mcf_pgalloc.h
> @@ -39,10 +39,7 @@ extern inline pmd_t *pmd_alloc_kernel(pgd_t *pgd, unsigned long address)
>  static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pgtable,
>  				  unsigned long address)
>  {
> -	struct ptdesc *ptdesc = virt_to_ptdesc(pgtable);
> -
> -	pagetable_dtor(ptdesc);
> -	pagetable_free(ptdesc);
> +	tlb_remove_ptdesc(tlb, virt_to_ptdesc(pgtable));
>  }
>  
>  static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
>