netdev - Re: [PATCH v0 5/5] cgroup: Assign subsystem IDs during compile time

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: <502E0552.3080602@monom.org>
Date:	Fri, 17 Aug 2012 10:48:18 +0200
From:	Daniel Wagner <wagi@...om.org>
To:	Li Zefan <lizefan@...wei.com>
CC:	Tejun Heo <tj@...nel.org>, netdev@...r.kernel.org,
	cgroups@...r.kernel.org,
	Daniel Wagner <daniel.wagner@...-carit.de>,
	"David S. Miller" <davem@...emloft.net>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Gao feng <gaofeng@...fujitsu.com>,
	Glauber Costa <glommer@...allels.com>,
	Jamal Hadi Salim <jhs@...atatu.com>,
	John Fastabend <john.r.fastabend@...el.com>,
	Kamezawa Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Neil Horman <nhorman@...driver.com>
Subject: Re: [PATCH v0 5/5] cgroup: Assign subsystem IDs during compile time

On 17.08.2012 09:25, Li Zefan wrote:
> On 2012/8/17 7:20, Tejun Heo wrote:
>> On Thu, Aug 16, 2012 at 04:12:16PM +0200, Daniel Wagner wrote:
>>> From: Daniel Wagner <daniel.wagner@...-carit.de>
>>>
>>> We are able to safe some space when we assign the subsystem
>>> IDs at compile time. Instead of allocating per cgroup
>>> cgroup->subsys[CGROUP_SUBSYS_COUNT] where CGROUP_SUBSYS_COUNT is
>>> always 64, we allocate 12 + 1 at max (at this point there are 12
>>> subsystem).
>>
>> So, IIUC, this is effectively removing the capability to implement
>> modularized controller which isn't known at kernel compile time.  Am I
>> right?
>>
>
> I think so.

I am preparing an updated version which does not need the extra 1 
pointer. Some more preprocessor magic involved :)

>> I don't think that's a bad idea but if we're doing that, can't we make
>> things even simpler?  Do we need to distinguish in-kernel and module
>> at all?
>>
>> Li, what do you think about this?
>>
>
> I'm definitely all for simplicity, but I'm not sure if we can do better in
> simplifying the code for modularized cgroup subsystem. (I guess you didn't
> mean to remove this feature?)

The new version should also be simpler to review because I don't have to 
touch the loops everywhere.

daniel



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html