linux-kernel - Re: [patch 12/16] sched: prevent interactions with throttled entities

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]

Date:	Thu, 23 Jun 2011 13:49:19 +0200
From:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
To:	Paul Turner <pjt@...gle.com>
Cc:	linux-kernel@...r.kernel.org,
	Bharata B Rao <bharata@...ux.vnet.ibm.com>,
	Dhaval Giani <dhaval.giani@...il.com>,
	Balbir Singh <balbir@...ux.vnet.ibm.com>,
	Vaidyanathan Srinivasan <svaidy@...ux.vnet.ibm.com>,
	Srivatsa Vaddagiri <vatsa@...ibm.com>,
	Kamalesh Babulal <kamalesh@...ux.vnet.ibm.com>,
	Hidetoshi Seto <seto.hidetoshi@...fujitsu.com>,
	Ingo Molnar <mingo@...e.hu>, Pavel Emelyanov <xemul@...nvz.org>
Subject: Re: [patch 12/16] sched: prevent interactions with throttled
 entities

On Tue, 2011-06-21 at 00:17 -0700, Paul Turner wrote:
> @@ -2635,8 +2704,10 @@ static int update_shares_cpu(struct task
>  
>         raw_spin_lock_irqsave(&rq->lock, flags);
>  
> -       update_rq_clock(rq);
> -       update_cfs_load(cfs_rq, 1);
> +       if (!throttled_hierarchy(cfs_rq)) {
> +               update_rq_clock(rq);
> +               update_cfs_load(cfs_rq, 1);
> +       }
>  
>         /* 

OK, so we can't contribute to load since we're throttled, but
tg->load_weight might have changed meanwhile?

Also, update_cfs_shares()->reweight_entity() can dequeue/enqueue the
entity, doesn't that require an up-to-date rq->clock?


--
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/