lkml.org 
[lkml]   [2014]   [Dec]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] mm:add VM_BUG_ON() for page_mapcount()
On Mon, Dec 08, 2014 at 03:47:47PM +0800, Wang, Yalin wrote:
> This patch add VM_BUG_ON() for slab page,
> because _mapcount is an union with slab struct in struct page,
> avoid access _mapcount if this page is a slab page.
> Also remove the unneeded bracket.
>
> Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
> ---
> include/linux/mm.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 11b65cf..34124c4 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -373,7 +373,8 @@ static inline void reset_page_mapcount(struct page *page)
>
> static inline int page_mapcount(struct page *page)
> {
> - return atomic_read(&(page)->_mapcount) + 1;
> + VM_BUG_ON(PageSlab(page));

VM_BUG_ON_PAGE(), please.

--
Kirill A. Shutemov


\
 
 \ /
  Last update: 2014-12-08 13:21    [W:0.168 / U:0.148 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site