From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH v2 1/2] x86: skip migrating IRQF_PER_CPU irq in fixup_irqs Date: Fri, 6 May 2011 09:58:28 -0400 Message-ID: <20110506135828.GC5500@dumpdata.com> References: <625BA99ED14B2D499DC4E29D8138F1505C8ED7F7E2@shsmsx502.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <625BA99ED14B2D499DC4E29D8138F1505C8ED7F7E2@shsmsx502.ccr.corp.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: "Tian, Kevin" Cc: "linux-kernel@vger.kernel.org" , "mingo@redhat.com" , "hpa@zytor.com" , "tglx@linutronix.de" , Ian Campbell , "JBeulich@novell.com" , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org On Fri, May 06, 2011 at 02:43:36PM +0800, Tian, Kevin wrote: > x86: skip migrating IRQF_PER_CPU irq in fixup_irqs > > IRQF_PER_CPU marks a irq binding to a specific cpu, and can never be > moved away from that cpu. So it shouldn't be migrated when fixup irqs > to offline a cpu. Xen pvops guest is one source using IRQF_PER_CPU ^- are called > on a set of virtual interrupts. Previously no error is observed ^^- was Which ones? Can you be more specific here of which type of virtual interrupts? spinlock? timer? > because Xen event chip silently fails the set_affinity ops, and > logically IRQF_PER_CPU should be recognized here. OK, so what if the set_affinity ops was implemented? > > Signed-off-by: Fengzhe Zhang > Signed-off-by: Kevin Tian > CC: Thomas Gleixner > CC: Ingo Molnar > CC: H. Peter Anvin > CC: Ian Campbell > CC: Jan Beulich > > --- linux-2.6.39-rc6.orig/arch/x86/kernel/irq.c 2011-05-04 10:59:13.000000000 +0800 > +++ linux-2.6.39-rc6/arch/x86/kernel/irq.c 2011-05-06 09:20:25.563963000 +0800 > @@ -249,7 +250,7 @@ void fixup_irqs(void) > > data = irq_desc_get_irq_data(desc); > affinity = data->affinity; > - if (!irq_has_action(irq) || > + if (!irq_has_action(irq) || irqd_is_per_cpu(data) || > cpumask_subset(affinity, cpu_online_mask)) { > raw_spin_unlock(&desc->lock); > continue; > -- > 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/