linux-kernel - Re: [RFC 6/8] In order putback lru core

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <BANLkTimPAU-uc=FCV9Z-LKmQm-GGusHfiw@mail.gmail.com>
Date:	Thu, 28 Apr 2011 08:59:17 +0900
From:	Minchan Kim <minchan.kim@...il.com>
To:	Rik van Riel <riel@...hat.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-mm <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Christoph Lameter <cl@...ux.com>,
	Johannes Weiner <jweiner@...hat.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Mel Gorman <mgorman@...e.de>,
	Andrea Arcangeli <aarcange@...hat.com>
Subject: Re: [RFC 6/8] In order putback lru core

Hi Rik,

On Thu, Apr 28, 2011 at 8:46 AM, Rik van Riel <riel@...hat.com> wrote:
> On 04/26/2011 12:25 PM, Minchan Kim wrote:
>
>> But this approach has a problem on contiguous pages.
>> In this case, my idea can not work since friend pages are isolated, too.
>> It means prev_page->next == next_page always is false and both pages are
>> not
>> LRU any more at that time. It's pointed out by Rik at LSF/MM summit.
>> So for solving the problem, I can change the idea.
>> I think we don't need both friend(prev, next) pages relation but
>> just consider either prev or next page that it is still same LRU.
>
>> Any comment?
>
> If the friend pages are isolated too, then your condition
> "either prev or next page that it is still same LRU" is
> likely to be false, no?

H - P1 - P2 - P3 - P4 - P5 - P6 - P7 - P8 - P9 - P10 - T

assume : we isolate pages P3~P7 and we consider only next pointer.

H - P1 - P2 - P8 - P9 - P10 - T

If we start to putback P7 as starting point, next P8 is valid so,

H - P1 - P2 - P7 - P8 - P9 - P10 - T
Then, if we consider P6, next P7 is valid, too. So,

H - P1 - P2 - P6 - P7 - P8 - P9 - P10 - T

continue until P3.


-- 
Kind regards,
Minchan Kim
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/