linux-kernel - [DISCUSSION] removing variety rq->cpu

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: <51AD4808.6020507@intel.com>
Date:	Tue, 04 Jun 2013 09:51:04 +0800
From:	Alex Shi <alex.shi@...el.com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
CC:	Paul Turner <pjt@...gle.com>, Ingo Molnar <mingo@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Borislav Petkov <bp@...en8.de>,
	Namhyung Kim <namhyung@...nel.org>,
	Mike Galbraith <efault@....de>,
	Morten Rasmussen <morten.rasmussen@....com>,
	Vincent Guittot <vincent.guittot@...aro.org>,
	Preeti U Murthy <preeti@...ux.vnet.ibm.com>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Mel Gorman <mgorman@...e.de>, Rik van Riel <riel@...hat.com>,
	Michael Wang <wangyun@...ux.vnet.ibm.com>
Subject: [DISCUSSION] removing variety rq->cpu_load ?

resend with a new subject.

> Peter,
> 
> I just tried to remove the variety rq.cpu_load, by the following patch. 
> Because forkexec_idx and busy_idx are all zero, after the patch system just keep cpu_load[0]
> and remove other values.
> I tried the patch base 3.10-rc3 and latest tip/sched/core with benchmark dbench,tbench,
> aim7,hackbench. and oltp of sysbench. Seems performance doesn't change clear.
> So, for my tested machines, core2, NHM, SNB, with 2 or 4 CPU sockets, and above tested
> benchmark. We are fine to remove the variety cpu_load. 
> Don't know if there some other concerns on other scenarios.
> 
> ---
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 590d535..f0ca983 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -4626,7 +4626,7 @@ static inline void update_sd_lb_stats(struct lb_env *env,
>         if (child && child->flags & SD_PREFER_SIBLING)
>                 prefer_sibling = 1;
>  
> -       load_idx = get_sd_load_idx(env->sd, env->idle);
> +       load_idx = 0; //get_sd_load_idx(env->sd, env->idle);
>  
>         do {
>                 int local_group;
> 
> 


-- 
Thanks
    Alex
--
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/