linux-kernel - Re: [PATCH] memcg: make memcg's file mapped consistent with global VM

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: <20091028073212.GO16378@balbir.in.ibm.com>
Date:	Wed, 28 Oct 2009 13:02:12 +0530
From:	Balbir Singh <balbir@...ux.vnet.ibm.com>
To:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"nishimura@....nes.nec.co.jp" <nishimura@....nes.nec.co.jp>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>
Subject: Re: [PATCH] memcg: make memcg's file mapped consistent with global
 VM

* KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com> [2009-10-28 16:24:58]:

> On Wed, 28 Oct 2009 12:48:54 +0530
> Balbir Singh <balbir@...ux.vnet.ibm.com> wrote:
> 
> > * KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com> [2009-10-28 12:16:19]:
> > 
> > > Based on mmotm-Oct13 + some patches in -mm queue.
> > > 
> > > ==
> > > From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
> > > 
> > > memcg-cleanup-file-mapped-consistent-with-globarl-vm-stat.patch
> > > 
> > > In global VM, FILE_MAPPED is used but memcg uses MAPPED_FILE.
> > > This makes grep difficult. Replace memcg's MAPPED_FILE with FILE_MAPPED
> > > 
> > > And in global VM, mapped shared memory is accounted into FILE_MAPPED.
> > > But memcg doesn't. fix it.
> > 
> > I wanted to explicitly avoid this since I wanted to do an iterative
> > correct accounting of shared memory. The renaming is fine with me
> > since we don't break ABI in user space.
> > 
> To do that, FILE_MAPPED is not correct.
> Because MAPPED includes shmem in global VM, no valid reason to do different
> style of counting.

OK, fair enough! Lets count shmem in FILE_MAPPED

> 
> For shmem, we have a charge type as MEM_CGROUP_CHARGE_TYPE_SHMEM and 
> we can set "PCG_SHMEM" flag onto page_cgroup or some.
> Then, we can count it in explicit way. 
>

Apart from shmem, I want to count all memory that is shared (mapcount > 1),
I'll send out an RFC once I have the implementation. For now, I
want to focus on testing memcg a bit more and start looking at some
aspects of dirty accounting.

-- 
	Balbir
--
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/