From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754057Ab1H2P2l (ORCPT <rfc822;w@1wt.eu>);
	Mon, 29 Aug 2011 11:28:41 -0400
Received: from merlin.infradead.org ([205.233.59.134]:37574 "EHLO
	merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1754022Ab1H2P2j convert rfc822-to-8bit (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 29 Aug 2011 11:28:39 -0400
Subject: Re: [PATCH 13/32] nohz: Adaptive tick stop and restart on nohz
 cpuset
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Anton Blanchard <anton@au1.ibm.com>, Avi Kivity <avi@redhat.com>,
        Ingo Molnar <mingo@elte.hu>, Lai Jiangshan <laijs@cn.fujitsu.com>,
        "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
        Paul Menage <menage@google.com>,
        Stephen Hemminger <shemminger@vyatta.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Tim Pepper <lnxninja@linux.vnet.ibm.com>
Date: Mon, 29 Aug 2011 17:28:09 +0200
In-Reply-To: <1313423549-27093-14-git-send-email-fweisbec@gmail.com>
References: <1313423549-27093-1-git-send-email-fweisbec@gmail.com>
	 <1313423549-27093-14-git-send-email-fweisbec@gmail.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8BIT
X-Mailer: Evolution 3.0.2- 
Message-ID: <1314631689.2816.91.camel@twins>
Mime-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, 2011-08-15 at 17:52 +0200, Frederic Weisbecker wrote:
> +bool cpuset_nohz_can_stop_tick(void)
> +{
> +       struct rq *rq;
> +
> +       rq = this_rq();
> +
> +       /* More than one running task need preemption */
> +       if (rq->nr_running > 1)
> +               return false;
> +
> +       return true;
> +} 

int sched_needs_cpu(int cpu), seems the right name, matches the existing
{rcu,printk,arch}_needs_cpu() functions.