From: Peter Zijlstra <peterz@infradead.org>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
David Howells <dhowells@redhat.com>,
torvalds@linux-foundation.org, Enrik.Berkhan@ge.com,
uclinux-dev@uclinux.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] NOMMU: Pages allocated to a ramfs inode's pagecache may get wrongly discarded
Date: Fri, 13 Mar 2009 08:57:16 +0100 [thread overview]
Message-ID: <1236931036.5188.80.camel@laptop> (raw)
In-Reply-To: <20090313105618.43DF.A69D9226@jp.fujitsu.com>
On Fri, 2009-03-13 at 11:03 +0900, KOSAKI Motohiro wrote:
> Hi
>
> > > Which as Peter points out:
> > >
> > > The ramfs stuff is rather icky in that it adds the pages to the aging
> > > list, marks them dirty, but does not provide a writeout method.
> > >
> > > This will make the paging code scan over them (continuously) trying to
> > > clean them, failing that (lack of writeout method) and putting them back
> > > on the list.
> > >
> > > Not requiring the pages to be added to the LRU would be a really good idea.
> > > They are not discardable, be it in MMU or NOMMU mode, except when the inode
> > > itself is discarded.
> >
> > Yep, these pages shouldn't be on the LRU at all. I guess that will
> > require some tweaks to core filemap.c code.
>
> IMHO, UNEVICTABLE_LRU already does lru isolation.
> only rest prblem is, getting rid of "depends on MMU" line in mm/Kconfig.
>
> Am I missing anything?
Yes, the need to take something off that shouldn't be there to begin
with.
next prev parent reply other threads:[~2009-03-13 7:58 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-11 15:30 David Howells
2009-03-11 17:26 ` Johannes Weiner
2009-03-11 22:03 ` Andrew Morton
2009-03-11 22:36 ` Johannes Weiner
2009-03-12 0:02 ` Andrew Morton
2009-03-12 0:35 ` Minchan Kim
2009-03-12 1:04 ` KOSAKI Motohiro
2009-03-12 1:52 ` Minchan Kim
2009-03-12 1:56 ` Minchan Kim
2009-03-12 2:00 ` KOSAKI Motohiro
2009-03-12 2:11 ` Minchan Kim
2009-03-12 12:19 ` Robin Getz
2009-03-12 17:55 ` [uClinux-dev] " Jamie Lokier
2009-03-13 17:33 ` [PATCH 0/2] Make the Unevictable LRU available on NOMMU David Howells
2009-03-13 17:33 ` [PATCH 1/2] NOMMU: There is no mlock() for NOMMU, so don't provide the bits David Howells
2009-03-14 11:17 ` KOSAKI Motohiro
2009-03-13 17:33 ` [PATCH 2/2] NOMMU: Make CONFIG_UNEVICTABLE_LRU available when CONFIG_MMU=n David Howells
2009-03-14 11:17 ` KOSAKI Motohiro
2009-03-14 0:27 ` [PATCH 0/2] Make the Unevictable LRU available on NOMMU Minchan Kim
2009-03-20 16:08 ` Lee Schermerhorn
2009-03-20 16:24 ` David Howells
2009-03-20 18:30 ` Lee Schermerhorn
2009-03-21 10:20 ` Johannes Weiner
2009-03-22 20:13 ` [patch 1/3] mm: decouple unevictable lru from mmu Johannes Weiner
2009-03-22 23:46 ` KOSAKI Motohiro
2009-03-23 0:14 ` Johannes Weiner
2009-03-23 10:48 ` David Howells
2009-03-22 20:13 ` [patch 2/3] ramfs-nommu: use generic lru cache Johannes Weiner
2009-03-23 2:22 ` KOSAKI Motohiro
2009-03-22 20:13 ` [patch 3/3] mm: keep pages from unevictable mappings off the LRU lists Johannes Weiner
2009-03-23 0:44 ` Minchan Kim
2009-03-23 2:21 ` KOSAKI Motohiro
2009-03-23 8:42 ` Johannes Weiner
2009-03-23 9:01 ` KOSAKI Motohiro
2009-03-23 9:23 ` KOSAKI Motohiro
2009-03-26 0:48 ` Johannes Weiner
2009-03-23 10:40 ` [patch 2/3] ramfs-nommu: use generic lru cache David Howells
2009-03-23 10:53 ` [patch 3/3] mm: keep pages from unevictable mappings off the LRU lists David Howells
2009-03-26 0:01 ` Johannes Weiner
2009-03-26 8:56 ` KOSAKI Motohiro
2009-03-26 10:36 ` Johannes Weiner
2009-03-23 20:07 ` [PATCH 0/2] Make the Unevictable LRU available on NOMMU Lee Schermerhorn
2009-03-13 11:53 ` [PATCH] NOMMU: Pages allocated to a ramfs inode's pagecache may get wrongly discarded David Howells
2009-03-13 22:49 ` Johannes Weiner
2009-03-12 0:08 ` Andrew Morton
2009-03-12 7:12 ` Berkhan, Enrik (GE Infra, Oil & Gas)
2009-03-12 11:29 ` [uClinux-dev] " Jamie Lokier
2009-03-12 11:50 ` Peter Zijlstra
2009-03-12 23:20 ` Minchan Kim
2009-03-13 7:56 ` Peter Zijlstra
2009-03-13 9:17 ` Minchan Kim
2009-03-12 12:25 ` David Howells
2009-03-12 19:43 ` Andrew Morton
2009-03-13 2:03 ` KOSAKI Motohiro
2009-03-13 7:57 ` Peter Zijlstra [this message]
2009-03-13 8:15 ` KOSAKI Motohiro
2009-03-13 9:19 ` Minchan Kim
2009-03-13 10:44 ` Johannes Weiner
2009-03-14 14:29 ` KOSAKI Motohiro
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=1236931036.5188.80.camel@laptop \
--to=peterz@infradead.org \
--cc=Enrik.Berkhan@ge.com \
--cc=akpm@linux-foundation.org \
--cc=dhowells@redhat.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=uclinux-dev@uclinux.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
Powered by JetHome