From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752245AbaHOInw (ORCPT ); Fri, 15 Aug 2014 04:43:52 -0400 Received: from service87.mimecast.com ([91.220.42.44]:35587 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750817AbaHOInv convert rfc822-to-8bit (ORCPT ); Fri, 15 Aug 2014 04:43:51 -0400 Message-ID: <53EDC89F.4020300@arm.com> Date: Fri, 15 Aug 2014 09:45:19 +0100 From: Sudeep Holla User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Neil Zhang , "linux@arm.linux.org.uk" CC: Sudeep Holla , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] arm: irq: fix the affinity when migrate a irq References: <1408087917-22603-1-git-send-email-zhangwm@marvell.com> In-Reply-To: <1408087917-22603-1-git-send-email-zhangwm@marvell.com> X-OriginalArrivalTime: 15 Aug 2014 08:43:46.0962 (UTC) FILETIME=[073C1720:01CFB865] X-MC-Unique: 114081509434901901 Content-Type: text/plain; charset=WINDOWS-1252; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Neil, On 15/08/14 08:31, Neil Zhang wrote: > Commit ffde1de64012 ("irqchip: Gic: Support forced affinity setting") > has enable the forcing cpu affinity of interrupts for gic. > > The current code of migrate_one_irq will pass the current affinity mask > to irq_set_affinity with force is true, it may select the cpu being > offlined as the target CPU again, then the interrupt won't be migrated > correctly. > I had posted similar patch [1] a while ago and the discussion[2] did not conclude. We need feedback from Thomas Gleixner. Regards, Sudeep [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-May/254838.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-June/265191.html > Signed-off-by: Neil Zhang > --- > arch/arm/kernel/irq.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c > index 2c42576..6f5a878 100644 > --- a/arch/arm/kernel/irq.c > +++ b/arch/arm/kernel/irq.c > @@ -167,11 +167,10 @@ static bool migrate_one_irq(struct irq_desc *desc) > if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity)) > return false; > > - if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) { > - affinity = cpu_online_mask; > + if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) > ret = true; > - } > > + affinity = cpu_online_mask; > c = irq_data_get_irq_chip(d); > if (!c->irq_set_affinity) > pr_debug("IRQ%u: unable to set affinity\n", d->irq); >