From: "Hillf Danton" <hillf.zj@alibaba-inc.com>
To: <Yalin.Wang@sonymobile.com>
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>,
<linux-mm@kvack.org>, <linux-arm-kernel@lists.infradead.org>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Hillf Danton" <hillf.zj@alibaba-inc.com>
Subject: Re: [PATCH] mm:add VM_BUG_ON() for page_mapcount()
Date: Mon, 08 Dec 2014 17:33:26 +0800 [thread overview]
Message-ID: <010b01d012ca$05244060$0f6cc120$@alibaba-inc.com> (raw)
>
> 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));
s/ VM_BUG_ON/ VM_BUG_ON_PAGE/ ?
> + return atomic_read(&page->_mapcount) + 1;
> }
>
next reply other threads:[~2014-12-08 9:34 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-08 9:33 Hillf Danton [this message]
2014-12-08 9:51 ` [PATCH] mm:add VM_BUG_ON() for page_mapcount() Wang, Yalin
2014-12-08 9:58 ` [PATCH V2] " Wang, Yalin
2014-12-08 9:59 ` [PATCH V3] mm:add VM_BUG_ON_PAGE() " Wang, Yalin
2014-12-08 11:54 ` Kirill A. Shutemov
2014-12-09 3:18 ` Hillf Danton
2015-06-09 16:14 ` Vlastimil Babka
-- strict thread matches above, loose matches on Subject: below --
2014-12-05 8:57 [RFC] mm:add KPF_ZERO_PAGE flag for /proc/kpageflags Wang, Yalin
2014-12-05 10:21 ` [RFC V2] " Wang, Yalin
2014-12-08 7:47 ` [PATCH] mm:add VM_BUG_ON() for page_mapcount() Wang, Yalin
2014-12-08 11:50 ` Kirill A. Shutemov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='010b01d012ca$05244060$0f6cc120$@alibaba-inc.com' \
--to=hillf.zj@alibaba-inc.com \
--cc=Yalin.Wang@sonymobile.com \
--cc=akpm@linux-foundation.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).