From patchwork Thu Sep 24 09:32:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 7254721 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 37700BEEC1 for ; Thu, 24 Sep 2015 09:37:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 34C4120954 for ; Thu, 24 Sep 2015 09:37:32 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2D3A720932 for ; Thu, 24 Sep 2015 09:37:31 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zf2wT-0004d3-B2; Thu, 24 Sep 2015 09:35:53 +0000 Received: from szxga02-in.huawei.com ([119.145.14.65]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zf2wP-0003O5-5V for linux-arm-kernel@lists.infradead.org; Thu, 24 Sep 2015 09:35:51 +0000 Received: from 172.24.1.49 (EHLO szxeml427-hub.china.huawei.com) ([172.24.1.49]) by szxrg02-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id CTF71490; Thu, 24 Sep 2015 17:32:31 +0800 (CST) Received: from localhost (10.177.19.219) by szxeml427-hub.china.huawei.com (10.82.67.182) with Microsoft SMTP Server id 14.3.235.1; Thu, 24 Sep 2015 17:32:21 +0800 From: Yang Yingliang To: , Subject: [RFC PATCH v6 1/3] genirq: introduce CONFIG_GENERIC_IRQ_MIGRATION and kernel/irq/cpuhotplug.c Date: Thu, 24 Sep 2015 17:32:13 +0800 Message-ID: <1443087135-17044-2-git-send-email-yangyingliang@huawei.com> X-Mailer: git-send-email 1.9.5.msysgit.1 In-Reply-To: <1443087135-17044-1-git-send-email-yangyingliang@huawei.com> References: <1443087135-17044-1-git-send-email-yangyingliang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.19.219] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150924_023550_105509_DFB3977F X-CRM114-Status: GOOD ( 22.82 ) X-Spam-Score: -4.2 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Russell King - ARM Linux , Marc Zyngier , Will Deacon , Hanjun Guo , Yang Yingliang , Thomas Gleixner , Jiang Liu Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add migrating interrupts code to a new file kernel/irq/cpuhotplug.c and make it depends on CONFIG_GENERIC_IRQ_MIGRATION. So we can use it to migrate interrupts, before cpu is offline. 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 --- include/linux/irq.h | 2 ++ kernel/irq/Kconfig | 4 +++ kernel/irq/Makefile | 1 + kernel/irq/cpuhotplug.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 75 insertions(+) create mode 100644 kernel/irq/cpuhotplug.c diff --git a/include/linux/irq.h b/include/linux/irq.h index 11bf092..45cc729 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -452,6 +452,8 @@ extern int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *cpumask, bool force); extern int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info); +extern void irq_migrate_all_off_this_cpu(void); + #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_PENDING_IRQ) void irq_move_irq(struct irq_data *data); void irq_move_masked_irq(struct irq_data *data); diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 9a76e3b..3b48dab 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -30,6 +30,10 @@ config GENERIC_IRQ_LEGACY_ALLOC_HWIRQ config GENERIC_PENDING_IRQ bool +# Support for generic irq migrating off cpu before the cpu is offline. +config GENERIC_IRQ_MIGRATION + bool + # Alpha specific irq affinity mechanism config AUTO_IRQ_AFFINITY bool diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index d121235..2fc9cbd 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -5,5 +5,6 @@ obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o +obj-$(CONFIG_GENERIC_IRQ_MIGRATION) += cpuhotplug.o obj-$(CONFIG_PM_SLEEP) += pm.o obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c new file mode 100644 index 0000000..8f2e9c0 --- /dev/null +++ b/kernel/irq/cpuhotplug.c @@ -0,0 +1,68 @@ +#include +#include +#include + +#include "internals.h" + +static bool migrate_one_irq(struct irq_desc *desc) +{ + struct irq_data *d = irq_desc_get_irq_data(desc); + const struct cpumask *affinity = d->common->affinity; + 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_warn_ratelimited("IRQ%u: unable to set affinity\n", d->irq); + } else { + int r = irq_do_set_affinity(d, affinity, false); + if (r) + pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n", d->irq, r); + } + + 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 irq_migrate_all_off_this_cpu(void) +{ + unsigned int irq; + struct irq_desc *desc; + unsigned long flags; + + local_irq_save(flags); + + for_each_active_irq(irq) { + bool affinity_broken; + + desc = irq_to_desc(irq); + 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", + irq, smp_processor_id()); + } + + local_irq_restore(flags); +}