Re: [PATCH v7 06/12] powerpc: inline huge vmap supported functions

From: Michael Ellerman
Date: Wed Aug 26 2020 - 08:00:00 EST


Nicholas Piggin <npiggin@xxxxxxxxx> writes:
> This allows unsupported levels to be constant folded away, and so
> p4d_free_pud_page can be removed because it's no longer linked to.
>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
> ---
>
> Ack or objection if this goes via the -mm tree?

Fine by me if it builds.

Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>

cheers

> diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
> index 105abb73f075..3f0c153befb0 100644
> --- a/arch/powerpc/include/asm/vmalloc.h
> +++ b/arch/powerpc/include/asm/vmalloc.h
> @@ -1,12 +1,25 @@
> #ifndef _ASM_POWERPC_VMALLOC_H
> #define _ASM_POWERPC_VMALLOC_H
>
> +#include <asm/mmu.h>
> #include <asm/page.h>
>
> #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> -bool arch_vmap_p4d_supported(pgprot_t prot);
> -bool arch_vmap_pud_supported(pgprot_t prot);
> -bool arch_vmap_pmd_supported(pgprot_t prot);
> +static inline bool arch_vmap_p4d_supported(pgprot_t prot)
> +{
> + return false;
> +}
> +
> +static inline bool arch_vmap_pud_supported(pgprot_t prot)
> +{
> + /* HPT does not cope with large pages in the vmalloc area */
> + return radix_enabled();
> +}
> +
> +static inline bool arch_vmap_pmd_supported(pgprot_t prot)
> +{
> + return radix_enabled();
> +}
> #endif
>
> #endif /* _ASM_POWERPC_VMALLOC_H */
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index eca83a50bf2e..27f5837cf145 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -1134,22 +1134,6 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
> set_pte_at(mm, addr, ptep, pte);
> }
>
> -bool arch_vmap_pud_supported(pgprot_t prot)
> -{
> - /* HPT does not cope with large pages in the vmalloc area */
> - return radix_enabled();
> -}
> -
> -bool arch_vmap_pmd_supported(pgprot_t prot)
> -{
> - return radix_enabled();
> -}
> -
> -int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
> -{
> - return 0;
> -}
> -
> int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
> {
> pte_t *ptep = (pte_t *)pud;
> @@ -1233,8 +1217,3 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
>
> return 1;
> }
> -
> -bool arch_vmap_p4d_supported(pgprot_t prot)
> -{
> - return false;
> -}
> --
> 2.23.0