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From: Suresh Siddha <suresh.b.siddha@intel.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>,
	Ingo Molnar <mingo@elte.hu>,
	Peter Zijlstra <peterz@infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Andi Kleen <ak@linux.intel.com>,
	Venki Pallipadi <venki@google.com>
Subject: Re: [Patch] Idle balancer: cache align nohz structure to improve idle load balancing scalability
Date: Wed, 19 Oct 2011 22:57:44 -0700	[thread overview]
Message-ID: <1319090264.14569.1.camel@sbsiddha-mobl2> (raw)
In-Reply-To: <1319084319.8416.38.camel@edumazet-laptop>

On Wed, 2011-10-19 at 21:18 -0700, Eric Dumazet wrote:
> > +	atomic_t load_balancer ____cacheline_aligned;
> > +	atomic_t first_pick_cpu ____cacheline_aligned;
> > +	atomic_t second_pick_cpu ____cacheline_aligned;
> > +	cpumask_var_t idle_cpus_mask ____cacheline_aligned;
> >  	cpumask_var_t grp_idle_mask;
> >  	unsigned long next_balance;     /* in jiffy units */
> >  } nohz ____cacheline_aligned;
> > 
> 
> Dont you increase cache footprint, say for an Uniprocessor machine ?
> 
> (CONFIG_SMP=n)
> 
> ____cacheline_aligned_in_smp seems more suitable in this case.

I believe this code is already under ifdef CONFIG_SMP.

thanks,
suresh



  reply	other threads:[~2011-10-20  5:58 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-19 21:45 [Patch] Idle balancer: cache align nohz structure to improve idle load balancing scalability Tim Chen
2011-10-20  4:18 ` Eric Dumazet
2011-10-20  5:57   ` Suresh Siddha [this message]
2011-10-20  6:43     ` Eric Dumazet
2011-10-20 17:19   ` Tim Chen
2011-10-20  4:24 ` Andi Kleen
2011-10-20 12:26   ` Venki Pallipadi
2011-10-20 17:31     ` Suresh Siddha
2011-10-20 17:38     ` Peter Zijlstra
     [not found]     ` <4FF5AC937153B0459463C1A88EB478F20135D6ECB5@orsmsx505.amr.corp.intel.com>
2011-11-01 23:52       ` Suresh Siddha
2011-11-02 13:04         ` Srivatsa Vaddagiri
2011-11-02 13:54         ` Srivatsa Vaddagiri
2011-11-02 15:13           ` Suresh Siddha
2011-11-14  9:32         ` Peter Zijlstra
2011-11-14 19:37           ` Suresh Siddha

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