Re: [PATCH 4/7] mm: Remove ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO

From: Mike Rapoport <rppt@kernel.org>
To: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org
Subject: Re: [PATCH 4/7] mm: Remove ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO
Date: Sun, 12 Feb 2023 17:51:18 +0200	[thread overview]
Message-ID: <Y+kK9qXSKXv+PrqA@kernel.org> (raw)
In-Reply-To: <20230211033948.891959-5-willy@infradead.org>

On Sat, Feb 11, 2023 at 03:39:45AM +0000, Matthew Wilcox (Oracle) wrote:
> Current best practice is to reuse the name of the function as a define
> to indicate that the function is implemented by the architecture.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
>  include/linux/cacheflush.h | 4 ++--
>  mm/util.c                  | 2 +-

I'd expect a change in arch/ that removes
ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO and adds #define flush_dcache_folio

What am I missing?

>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/cacheflush.h b/include/linux/cacheflush.h
> index a6189d21f2ba..82136f3fcf54 100644
> --- a/include/linux/cacheflush.h
> +++ b/include/linux/cacheflush.h
> @@ -7,14 +7,14 @@
>  struct folio;
>  
>  #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
> -#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO
> +#ifndef flush_dcache_folio
>  void flush_dcache_folio(struct folio *folio);
>  #endif
>  #else
>  static inline void flush_dcache_folio(struct folio *folio)
>  {
>  }
> -#define ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO 0
> +#define flush_dcache_folio flush_dcache_folio
>  #endif /* ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE */
>  
>  #endif /* _LINUX_CACHEFLUSH_H */
> diff --git a/mm/util.c b/mm/util.c
> index cec9327b27b4..39ea7af8171c 100644
> --- a/mm/util.c
> +++ b/mm/util.c
> @@ -1124,7 +1124,7 @@ void page_offline_end(void)
>  }
>  EXPORT_SYMBOL(page_offline_end);
>  
> -#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO
> +#ifndef flush_dcache_folio
>  void flush_dcache_folio(struct folio *folio)
>  {
>  	long i, nr = folio_nr_pages(folio);
> -- 
> 2.39.1
> 
> 

-- 
Sincerely yours,
Mike.