linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Qian Cai <cai@lca.pw>
To: Matthew Wilcox <willy@infradead.org>
Cc: Huang Ying <ying.huang@intel.com>, linux-mm@kvack.org
Subject: Re: page cache: Store only head pages in i_pages
Date: Sun, 24 Mar 2019 11:42:23 -0400	[thread overview]
Message-ID: <0d7ae84f-268a-aefc-ee01-5db9b7327c8e@lca.pw> (raw)
In-Reply-To: <20190324030422.GE10344@bombadil.infradead.org>



On 3/23/19 11:04 PM, Matthew Wilcox wrote:
> The patch for you should have looked like this:
> 
> @@ -335,11 +335,12 @@ static inline struct page *grab_cache_page_nowait(struct address_space *mapping,
>  
>  static inline struct page *find_subpage(struct page *page, pgoff_t offset)
>  {
> +       unsigned long index = page_index(page);
> +
>         VM_BUG_ON_PAGE(PageTail(page), page);
> -       VM_BUG_ON_PAGE(page->index > offset, page);
> -       VM_BUG_ON_PAGE(page->index + (1 << compound_order(page)) <= offset,
> -                       page);
> -       return page - page->index + offset;
> +       VM_BUG_ON_PAGE(index > offset, page);
> +       VM_BUG_ON_PAGE(index + (1 << compound_order(page)) <= offset, page);
> +       return page - index + offset;
>  }

It works great.


  reply	other threads:[~2019-03-24 15:42 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1553285568.26196.24.camel@lca.pw>
2019-03-23  3:38 ` page cache: Store only head pages in i_pages Matthew Wilcox
2019-03-23 23:50   ` Qian Cai
2019-03-24  2:06     ` Matthew Wilcox
2019-03-24  2:52       ` Qian Cai
2019-03-24  3:04         ` Matthew Wilcox
2019-03-24 15:42           ` Qian Cai [this message]
2019-03-27 10:48           ` William Kucharski
2019-03-27 11:50             ` Matthew Wilcox
2019-03-29  1:43           ` Qian Cai
2019-03-29 19:59             ` Matthew Wilcox
2019-03-29 21:25               ` Qian Cai
2019-03-30  3:04                 ` Matthew Wilcox
2019-03-30 14:10                   ` Matthew Wilcox
2019-03-31  3:23                     ` Matthew Wilcox
2019-04-01  9:18                       ` Kirill A. Shutemov
2019-04-01  9:27                         ` Kirill A. Shutemov
2019-04-04 13:10                           ` Qian Cai
2019-04-04 13:45                             ` Kirill A. Shutemov
2019-04-04 21:28                               ` Qian Cai
2019-04-05 13:37                                 ` Kirill A. Shutemov
2019-04-05 13:51                                   ` Matthew Wilcox

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=0d7ae84f-268a-aefc-ee01-5db9b7327c8e@lca.pw \
    --to=cai@lca.pw \
    --cc=linux-mm@kvack.org \
    --cc=willy@infradead.org \
    --cc=ying.huang@intel.com \
    /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).