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Subject: Re: [tg_shares_up rewrite v3 09/11] sched: demand based
 update_cfs_load()
From: Peter Zijlstra <peterz@infradead.org>
To: Paul Turner <pjt@google.com>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
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Date: Fri, 12 Nov 2010 13:12:39 +0100
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On Fri, 2010-11-12 at 11:53 +0100, Peter Zijlstra wrote:
> On Thu, 2010-11-11 at 19:24 -0800, Paul Turner wrote:
> > +#ifdef CONFIG_FAIR_GROUP_SCHED
> > +       cfs_rq->load_unacc_exec_time += delta_exec;
> > +       if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window)
> > {
> > +               update_cfs_load(cfs_rq);
> > +               update_cfs_shares(cfs_rq, 0);
> 
> Why not:
> +		cfs_rq->load_unacc_exec_time -= sysctl_sched_shares_window;
> 
> (although you probably want to read the sysctl value into a local
> variable using ACCESS_ONCE() and use that for both cases).

Ah, I see why not, still that reset looks better here than in that other
function.