From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753320AbbIQFfe (ORCPT ); Thu, 17 Sep 2015 01:35:34 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:22028 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbbIQFfd (ORCPT ); Thu, 17 Sep 2015 01:35:33 -0400 From: Yang Yingliang To: , CC: Yang Yingliang , Jiang Liu , Thomas Gleixner , "Marc Zyngier" , Mark Rutland , "Will Deacon" , Russell King - ARM Linux , Hanjun Guo Subject: [RFC PATCH v4 4/4] arm: fix a migrating irq bug when hotplug cpu Date: Thu, 17 Sep 2015 13:19:26 +0800 Message-ID: <1442467166-1460-5-git-send-email-yangyingliang@huawei.com> X-Mailer: git-send-email 1.9.5.msysgit.1 In-Reply-To: <1442467166-1460-1-git-send-email-yangyingliang@huawei.com> References: <1442467166-1460-1-git-send-email-yangyingliang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.177.19.219] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When cpu is disabled, all irqs will be migratged to another cpu. In some cases, a new affinity is different, it needed to be coppied to irq's affinity. But if the type of irq is LPI, it's affinity will not be coppied because of irq_set_affinity's return value. Fix it by using irq_do_set_affinity. And migrating interrupts is a core code matter, so use the generic function move_irqs() to migrate interrupts in kernel/irq/migration.c. Cc: Jiang Liu Cc: Thomas Gleixner Cc: Marc Zyngier Cc: Mark Rutland Cc: Will Deacon Cc: Russell King - ARM Linux Cc: Hanjun Guo Signed-off-by: Yang Yingliang --- arch/arm/Kconfig | 1 + arch/arm/include/asm/irq.h | 1 - arch/arm/kernel/irq.c | 62 ---------------------------------------------- arch/arm/kernel/smp.c | 2 +- 4 files changed, 2 insertions(+), 64 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 72ad724..bffba78 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1492,6 +1492,7 @@ config NR_CPUS config HOTPLUG_CPU bool "Support for hot-pluggable CPUs" depends on SMP + select GENERIC_IRQ_MIGRATION help Say Y here to experiment with turning CPUs off and on. CPUs can be controlled through /sys/devices/system/cpu. diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h index be1d07d..882bf98 100644 --- a/arch/arm/include/asm/irq.h +++ b/arch/arm/include/asm/irq.h @@ -24,7 +24,6 @@ #ifndef __ASSEMBLY__ struct irqaction; struct pt_regs; -extern void migrate_irqs(void); extern void asm_do_IRQ(unsigned int, struct pt_regs *); void handle_IRQ(unsigned int, struct pt_regs *); diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c index 5ff4826..78abea8 100644 --- a/arch/arm/kernel/irq.c +++ b/arch/arm/kernel/irq.c @@ -31,7 +31,6 @@ #include #include #include -#include #include #include #include @@ -136,64 +135,3 @@ int __init arch_probe_nr_irqs(void) return nr_irqs; } #endif - -#ifdef CONFIG_HOTPLUG_CPU -static bool migrate_one_irq(struct irq_desc *desc) -{ - struct irq_data *d = irq_desc_get_irq_data(desc); - const struct cpumask *affinity = irq_data_get_affinity_mask(d); - struct irq_chip *c; - bool ret = false; - - /* - * If this is a per-CPU interrupt, or the affinity does not - * include this CPU, then we have nothing to do. - */ - 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; - ret = true; - } - - c = irq_data_get_irq_chip(d); - if (!c->irq_set_affinity) - pr_debug("IRQ%u: unable to set affinity\n", d->irq); - else if (c->irq_set_affinity(d, affinity, false) == IRQ_SET_MASK_OK && ret) - cpumask_copy(irq_data_get_affinity_mask(d), affinity); - - return ret; -} - -/* - * The current CPU has been marked offline. Migrate IRQs off this CPU. - * If the affinity settings do not allow other CPUs, force them onto any - * available CPU. - * - * Note: we must iterate over all IRQs, whether they have an attached - * action structure or not, as we need to get chained interrupts too. - */ -void migrate_irqs(void) -{ - unsigned int i; - struct irq_desc *desc; - unsigned long flags; - - local_irq_save(flags); - - for_each_irq_desc(i, desc) { - bool affinity_broken; - - raw_spin_lock(&desc->lock); - affinity_broken = migrate_one_irq(desc); - raw_spin_unlock(&desc->lock); - - if (affinity_broken) - pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n", - i, smp_processor_id()); - } - - local_irq_restore(flags); -} -#endif /* CONFIG_HOTPLUG_CPU */ diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 48185a7..262ead7 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -218,7 +218,7 @@ int __cpu_disable(void) /* * OK - migrate IRQs away from this CPU */ - migrate_irqs(); + move_irqs(); /* * Flush user cache and TLB mappings, and then remove this CPU -- 2.5.0