Re: [PATCH V5 1/3] mm/thp: Split out pmd collpase flush into a separate functions

["Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>]

 diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
> index 39f1d6a2b04d..acdcaac77d93 100644
> --- a/include/asm-generic/pgtable.h
> +++ b/include/asm-generic/pgtable.h
> @@ -189,6 +189,28 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma,
>  				 unsigned long address, pmd_t *pmdp);
>  #endif
>
> +#ifndef pmdp_collapse_flush
> +#define pmdp_collapse_flush pmdp_collapse_flush
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> +static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
> +					unsigned long address,
> +					pmd_t *pmdp)


extra pmdp_collapse_flush #define here

> +{
> +	return pmdp_clear_flush(vma, address, pmdp);
> +}
> +#define pmdp_collapse_flush pmdp_collapse_flush
> +#else
> +static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
> +					unsigned long address,
> +					pmd_t *pmdp)
> +{
> +	BUILD_BUG();
> +	return *pmdp;
> +}
> +#define pmdp_collapse_flush pmdp_collapse_flush
> +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
> +#endif
> +
>  #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
>  extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
>  				       pgtable_t pgtable);

diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index acdcaac77d93..2c3ca89e9aee 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -190,7 +190,6 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma,
 #endif
 
 #ifndef pmdp_collapse_flush
-#define pmdp_collapse_flush pmdp_collapse_flush
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
 					unsigned long address,