linux-kernel - Re: [patch 3/3] sched: move sched_avg_update() to update_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: <1282312043.2605.1033.camel@laptop>
Date:	Fri, 20 Aug 2010 15:47:23 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Suresh Siddha <suresh.b.siddha@...el.com>
Cc:	"mingo@...e.hu" <mingo@...e.hu>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"chris@...stnet.net" <chris@...stnet.net>,
	"debian00@...ceadsl.fr" <debian00@...ceadsl.fr>,
	"hpa@...or.com" <hpa@...or.com>,
	"jonathan.protzenko@...il.com" <jonathan.protzenko@...il.com>,
	"mans@...sr.com" <mans@...sr.com>,
	"psastudio@...l.ru" <psastudio@...l.ru>,
	"rjw@...k.pl" <rjw@...k.pl>,
	"stephan.eicher@....de" <stephan.eicher@....de>,
	"sxxe@....de" <sxxe@....de>,
	"thomas@...hlinux.org" <thomas@...hlinux.org>,
	"venki@...gle.com" <venki@...gle.com>,
	"wonghow@...il.com" <wonghow@...il.com>
Subject: Re: [patch 3/3] sched: move sched_avg_update() to update_cpu_load()

On Thu, 2010-08-19 at 17:51 -0700, Suresh Siddha wrote:
> 
> From: Suresh Siddha <suresh.b.siddha@...el.com>
> Subject: sched: move sched_avg_update() to update_cpu_load()
> 
> Currently sched_avg_update() (which updates rt_avg stats in the rq) is getting
> called from scale_rt_power() (in the load balance context) which doesn't take
> rq->lock.
> 
> Fix it by moving the sched_avg_update() to more appropriate update_cpu_load()
> where the CFS load gets updated aswell.
> 
> Signed-off-by: Suresh Siddha <suresh.b.siddha@...el.com>
> ---
>  kernel/sched.c      |    3 ++-
>  kernel/sched_fair.c |    2 --
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> Index: tree/kernel/sched_fair.c
> ===================================================================
> --- tree.orig/kernel/sched_fair.c
> +++ tree/kernel/sched_fair.c
> @@ -2268,8 +2268,6 @@ unsigned long scale_rt_power(int cpu)
>         struct rq *rq = cpu_rq(cpu);
>         u64 total, available;
>  
> -       sched_avg_update(rq);
> -
>         total = sched_avg_period() + (rq->clock - rq->age_stamp);
>         available = total - rq->rt_avg;
>  
> Index: tree/kernel/sched.c
> ===================================================================
> --- tree.orig/kernel/sched.c
> +++ tree/kernel/sched.c
> @@ -3182,6 +3182,8 @@ static void update_cpu_load(struct rq *t
>  
>                 this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
>         }
> +
> +       sched_avg_update(this_rq);
>  }
>  
>  static void update_cpu_load_active(struct rq *this_rq) 

breaks CONFIG_SMP=n builds..

  CC      kernel/sched.o
/usr/src/linux-2.6/kernel/sched.c: In function ‘update_cpu_load’:
/usr/src/linux-2.6/kernel/sched.c:3186: error: implicit declaration of function ‘sched_avg_update’  CC      kernel/sched.o
/usr/src/linux-2.6/kernel/sched.c: In function ‘update_cpu_load’:
/usr/src/linux-2.6/kernel/sched.c:3186: error: implicit declaration of function ‘sched_avg_update’


--
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/