Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752927AbaDXIl5 (ORCPT ); Thu, 24 Apr 2014 04:41:57 -0400 Received: from mail-ob0-f169.google.com ([209.85.214.169]:39724 "EHLO mail-ob0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752457AbaDXIlx (ORCPT ); Thu, 24 Apr 2014 04:41:53 -0400 MIME-Version: 1.0 In-Reply-To: <201404240832.s3O8WHd0011014@toshiba.co.jp> References: <201404240725.s3O7PrUv003720@toshiba.co.jp> <201404240832.s3O8WHd0011014@toshiba.co.jp> Date: Thu, 24 Apr 2014 14:11:52 +0530 Message-ID: Subject: Re: [RFC 0/4] Migrate timers away from cpuset on setting cpuset.quiesce From: Viresh Kumar To: Daniel Sangorrin Cc: Thomas Gleixner , =?UTF-8?B?RnLDqWTDqXJpYyBXZWlzYmVja2Vy?= , Peter Zijlstra , Ingo Molnar , Tejun Heo , Li Zefan , Lists linaro-kernel , Linux Kernel Mailing List , Cgroups Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24 April 2014 14:01, Daniel Sangorrin wrote: > In kernel/cpuset.c:quiesce_cpuset() you are using the function > 'smp_call_function_any' which asks CPU cores in 'cpumask' to > execute the functions 'hrtimer_quiesce_cpu' and 'timer_quiesce_cpu'. > > In the case above, 'cpumask' corresponds to core 0. Since I'm forcing > the call to be executed from core 1 (by using taskset), > an inter-processor interrupt is sent to core 0 for those functions > to be executed. Ahh, I understood that now :) .. So we are setting cpuset.quiesce from CPU1 which will do a IPI to get migrate_timers called on CPU0.. I was setting quiesce from CPU0 only in my tests :) But how does this work fine on x86 then? There we should have exactly same problem, isn't it? > Ok, thank you! I see that you have already fixed the problem. I tested > your tree on ARM and now it seems to work correctly. Yeah, I just pushed your changes as well at the time I wrote last mail :) -- 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/