linux-kernel - Re: [RFC/PATCH -v2] Add sysfs control to modify a user's cpu share

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: <20071004085451.GA8108@osiris.boeblingen.de.ibm.com>
Date:	Thu, 4 Oct 2007 10:54:51 +0200
From:	Heiko Carstens <heiko.carstens@...ibm.com>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Dhaval Giani <dhaval@...ux.vnet.ibm.com>,
	Srivatsa Vaddagiri <vatsa@...ux.vnet.ibm.com>,
	Mike Galbraith <efault@....de>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Dmitry Adamushko <dmitry.adamushko@...il.com>,
	lkml <linux-kernel@...r.kernel.org>, maneesh@...ux.vnet.ibm.com,
	Andrew Morton <akpm@...ux-foundation.org>,
	Sudhir Kumar <skumar@...ux.vnet.ibm.com>
Subject: Re: [RFC/PATCH -v2] Add sysfs control to modify a user's cpu share

> > Changelog since v1:
> > 1. Added a mutex to serialize directory creation/destruction for a user in
> >    sysfs
> > 2. Added a spinlock in the task_group structure to serialize writes to
> >    tg->shares.
> > 3. Removed /proc/root_user_cpu_shares.
> > 4. Added Documentation about the group scheduler.
> 
> thanks - I have added this to the queue.
> 
> i'm wondering about the following: could not (yet) existing UIDs be made 
> configurable too? I.e. if i do this in a bootup script:
> 
>   echo 2048 > /sys/kernel/uids/500/cpu_share
> 
> this should just work too, regardless of there not being any UID 500 
> tasks yet. Likewise, once configured, the /sys/kernel/uids/* directories 
> (with the settings in them) should probably not go away either.

Shouldn't that be done via uevents? E.g. UID x gets added to the sysfs tree,
generates a uevent and a script then figures out the cpu_share and sets it.
That way you also don't need to keep the directories. No?
-
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/