lkml.org 
[lkml]   [2011]   [Jan]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/7] Change page reference handling semantic of page cache
On Thu, Dec 23, 2010 at 12:32:42AM +0900, Minchan Kim wrote:
> Now we increases page reference on add_to_page_cache but doesn't decrease it
> in remove_from_page_cache. Such asymmetric makes confusing about
> page reference so that caller should notice it and comment why they
> release page reference. It's not good API.
>
> Long time ago, Hugh tried it[1] but gave up of reason which
> reiser4's drop_page had to unlock the page between removing it from
> page cache and doing the page_cache_release. But now the situation is
> changed. I think at least things in current mainline doesn't have any
> obstacles. The problem is fs or somethings out of mainline.
> If it has done such thing like reiser4, this patch could be a problem but
> they found it when compile time since we remove remove_from_page_cache.
>
> [1] http://lkml.org/lkml/2004/10/24/140
>
> The series configuration is following as.
>
> [1/7] : This patch introduces new API delete_from_page_cache.
> [2,3,4,5/7] : Change remove_from_page_cache with delete_from_page_cache.
> Intentionally I divide patch per file since someone might have a concern
> about releasing page reference of delete_from_page_cache in
> somecase (ex, truncate.c)
> [6/7] : Remove old API so out of fs can meet compile error when build time
> and can notice it.
> [7/7] : Change __remove_from_page_cache with __delete_from_page_cache, too.
> In this time, I made all-in-one patch because it doesn't change old behavior
> so it has no concern. Just clean up patch.
>

Other than hugetlbfs being called tlbfs in patch 3/7;

Acked-by: Mel Gorman <mel@csn.ul.ie>

--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab


\
 
 \ /
  Last update: 2011-01-06 11:33    [W:0.132 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site