From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751920AbdIMVfg (ORCPT ); Wed, 13 Sep 2017 17:35:36 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:40318 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751784AbdIMVfW (ORCPT ); Wed, 13 Sep 2017 17:35:22 -0400 Message-Id: <20170913213156.431670325@linutronix.de> User-Agent: quilt/0.63-1 Date: Wed, 13 Sep 2017 23:29:54 +0200 From: Thomas Gleixner To: LKML Cc: Ingo Molnar , Peter Anvin , Marc Zyngier , Peter Zijlstra , Borislav Petkov , Chen Yu , Rui Zhang , "Rafael J. Wysocki" , Len Brown , Dan Williams , Christoph Hellwig , Paolo Bonzini , Joerg Roedel , Boris Ostrovsky , Juergen Gross , Tony Luck , "K. Y. Srinivasan" , Alok Kataria , Steven Rostedt , Arjan van de Ven Subject: [patch 52/52] x86/vector: Respect affinity mask in irq descriptor References: <20170913212902.530704676@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=x86-vector--Respect-affinity-mask-in-irq-descriptor.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The interrupt descriptor has a preset affinity mask at allocation time, which is usually the default affinity mask. The current code does not respect that mask and places the vector at some random CPU, which gets corrected later by a set_affinity() call. That's silly because the vector allocation can respect the mask upfront and place the interrupt on a CPU which is in the mask. If that fails, then the affinity is broken and a interrupt assigned on any online CPU. Signed-off-by: Thomas Gleixner --- arch/x86/kernel/apic/vector.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -249,12 +249,25 @@ static int assign_irq_vector(struct irq_ static int assign_irq_vector_any_locked(struct irq_data *irqd) { + /* Get the affinity mask - either irq_default_affinity or (user) set */ + const struct cpumask *affmsk = irq_data_get_affinity_mask(irqd); int node = irq_data_get_node(irqd); - if (node != NUMA_NO_NODE) { - if (!assign_vector_locked(irqd, cpumask_of_node(node))) - return 0; - } + if (node == NUMA_NO_NODE) + goto all; + /* Try the intersection of @affmsk and node mask */ + cpumask_and(vector_searchmask, cpumask_of_node(node), affmsk); + if (!assign_vector_locked(irqd, vector_searchmask)) + return 0; + /* Try the node mask */ + if (!assign_vector_locked(irqd, cpumask_of_node(node))) + return 0; +all: + /* Try the full affinity mask */ + cpumask_and(vector_searchmask, affmsk, cpu_online_mask); + if (!assign_vector_locked(irqd, vector_searchmask)) + return 0; + /* Try the full online mask */ return assign_vector_locked(irqd, cpu_online_mask); }