Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751741AbaB1JEu (ORCPT ); Fri, 28 Feb 2014 04:04:50 -0500 Received: from mail-oa0-f41.google.com ([209.85.219.41]:45217 "EHLO mail-oa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751114AbaB1JEn (ORCPT ); Fri, 28 Feb 2014 04:04:43 -0500 MIME-Version: 1.0 In-Reply-To: <20140115113406.GC31570@twins.programming.kicks-ass.net> References: <20140115103808.GY31570@twins.programming.kicks-ass.net> <20140115113406.GC31570@twins.programming.kicks-ass.net> Date: Fri, 28 Feb 2014 14:34:42 +0530 Message-ID: Subject: Re: [QUERY]: Is using CPU hotplug right for isolating CPUs? From: Viresh Kumar To: Peter Zijlstra , Thomas Gleixner Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= , Kevin Hilman , Vincent Guittot , Amit Kucheria , Lists linaro-kernel , Linaro Networking , Linux Kernel Mailing List , Steven Rostedt Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15 January 2014 17:04, Peter Zijlstra wrote: > On Wed, Jan 15, 2014 at 04:17:26PM +0530, Viresh Kumar wrote: >> On 15 January 2014 16:08, Peter Zijlstra wrote: >> > Nah, its just ugly and we should fix it. You need to be careful to not >> > place tasks in a cpuset you're going to unplug though, that'll give >> > funny results. >> >> Okay. So how do you suggest to get rid of cases like a work queued >> on CPU1 initially and because it gets queued again from its work handler, >> it stays on the same CPU forever. > > We should have a cpuset.quiesce control or something that moves all > timers out. What should we do here if we have a valid base->running_timer for the cpu requesting the quiesce ? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/