From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69CCCC28CF6 for ; Wed, 1 Aug 2018 15:11:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BD70208A3 for ; Wed, 1 Aug 2018 15:11:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BD70208A3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389662AbeHAQ6E (ORCPT ); Wed, 1 Aug 2018 12:58:04 -0400 Received: from foss.arm.com ([217.140.101.70]:43854 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389557AbeHAQ6E (ORCPT ); Wed, 1 Aug 2018 12:58:04 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 188B97A9; Wed, 1 Aug 2018 08:11:55 -0700 (PDT) Received: from [10.4.13.159] (e112298-lin.emea.arm.com [10.4.13.159]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 05B2D3F5D0; Wed, 1 Aug 2018 08:11:53 -0700 (PDT) Subject: Re: [PATCH 2/4] genirq: Provide NMI management for percpu_devid interrupts To: Ricardo Neri Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, peterz@infradead.org, marc.zyngier@arm.com, mingo@kernel.org References: <1532430427-57151-1-git-send-email-julien.thierry@arm.com> <1532430427-57151-3-git-send-email-julien.thierry@arm.com> <20180801031104.GB31383@voyager> From: Julien Thierry Message-ID: <17bd4c2f-000e-3b32-49bf-b2700e74f66e@arm.com> Date: Wed, 1 Aug 2018 16:11:52 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180801031104.GB31383@voyager> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/08/18 04:11, Ricardo Neri wrote: > On Tue, Jul 24, 2018 at 12:07:05PM +0100, Julien Thierry wrote: >> Add support for percpu_devid interrupts treated as NMIs. >> >> Percpu_devid NMIs need to be setup/torn down on each CPU they target. >> >> The same restrictions as for global NMIs still apply for percpu_devid NMIs. >> >> Signed-off-by: Julien Thierry >> Cc: Thomas Gleixner >> Cc: Peter Zijlstra >> Cc: Ingo Molnar >> Cc: Marc Zyngier >> --- >> include/linux/interrupt.h | 9 +++ >> kernel/irq/manage.c | 149 ++++++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 158 insertions(+) >> >> diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h >> index 3b1a320..59d3877 100644 >> --- a/include/linux/interrupt.h >> +++ b/include/linux/interrupt.h >> @@ -168,10 +168,15 @@ struct irqaction { >> devname, percpu_dev_id); >> } >> >> +extern int __must_check >> +request_percpu_nmi(unsigned int irq, irq_handler_t handler, >> + const char *devname, void __percpu *dev); >> + >> extern const void *free_irq(unsigned int, void *); >> extern void free_percpu_irq(unsigned int, void __percpu *); >> >> extern const void *free_nmi(unsigned int irq, void *dev_id); >> +extern void free_percpu_nmi(unsigned int irq, void __percpu *percpu_dev_id); >> >> struct device; >> >> @@ -224,7 +229,11 @@ struct irqaction { >> extern void irq_wake_thread(unsigned int irq, void *dev_id); >> >> extern void disable_nmi_nosync(unsigned int irq); >> +extern void disable_percpu_nmi(unsigned int irq); > > Shouldn't this be a disable_percpu_nmi_nosync() as disable_nmi_nosync()? > The naming of the disable_percpu_irq didn't include the nosync either (and it doesn't wait for pending percpu_devid_irqs) >> extern void enable_nmi(unsigned int irq); >> +extern void enable_percpu_nmi(unsigned int irq, unsigned int type); >> +extern int ready_percpu_nmi(unsigned int irq); >> +extern void teardown_percpu_nmi(unsigned int irq); >> >> /* The following three functions are for the core kernel use only. */ >> extern void suspend_device_irqs(void); >> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c >> index 3b87143..ad41c4d 100644 >> --- a/kernel/irq/manage.c >> +++ b/kernel/irq/manage.c >> @@ -2162,6 +2162,11 @@ void enable_percpu_irq(unsigned int irq, unsigned int type) >> } >> EXPORT_SYMBOL_GPL(enable_percpu_irq); >> >> +void enable_percpu_nmi(unsigned int irq, unsigned int type) >> +{ >> + enable_percpu_irq(irq, type); >> +} >> + >> /** >> * irq_percpu_is_enabled - Check whether the per cpu irq is enabled >> * @irq: Linux irq number to check for >> @@ -2201,6 +2206,11 @@ void disable_percpu_irq(unsigned int irq) >> } >> EXPORT_SYMBOL_GPL(disable_percpu_irq); >> >> +void disable_percpu_nmi(unsigned int irq) >> +{ >> + disable_percpu_irq(irq); >> +} >> + >> /* >> * Internal function to unregister a percpu irqaction. >> */ >> @@ -2232,6 +2242,8 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_ >> /* Found it - now remove it from the list of entries: */ >> desc->action = NULL; >> >> + desc->istate &= ~IRQS_NMI; >> + >> raw_spin_unlock_irqrestore(&desc->lock, flags); >> >> unregister_handler_proc(irq, action); >> @@ -2285,6 +2297,19 @@ void free_percpu_irq(unsigned int irq, void __percpu *dev_id) >> } >> EXPORT_SYMBOL_GPL(free_percpu_irq); >> >> +void free_percpu_nmi(unsigned int irq, void __percpu *dev_id) >> +{ >> + struct irq_desc *desc = irq_to_desc(irq); >> + >> + if (!desc || !irq_settings_is_per_cpu_devid(desc)) >> + return; >> + >> + if (WARN_ON(!(desc->istate & IRQS_NMI))) >> + return; >> + >> + kfree(__free_percpu_irq(irq, dev_id)); >> +} >> + >> /** >> * setup_percpu_irq - setup a per-cpu interrupt >> * @irq: Interrupt line to setup >> @@ -2375,6 +2400,130 @@ int __request_percpu_irq(unsigned int irq, irq_handler_t handler, >> EXPORT_SYMBOL_GPL(__request_percpu_irq); >> >> /** >> + * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery >> + * @irq: Interrupt line to allocate >> + * @handler: Function to be called when the IRQ occurs. >> + * @devname: An ascii name for the claiming device >> + * @dev_id: A percpu cookie passed back to the handler function >> + * >> + * This call allocates interrupt resources and enables the >> + * interrupt on the local CPU. If the interrupt is supposed to be >> + * enabled on other CPUs, it has to be done on each CPU using >> + * enable_percpu_nmi(). >> + * >> + * Dev_id must be globally unique. It is a per-cpu variable, and >> + * the handler gets called with the interrupted CPU's instance of >> + * that variable. >> + * >> + * Interrupt lines requested for NMI delivering should have auto enabling >> + * setting disabled. >> + * >> + * If the interrupt line cannot be used to deliver NMIs, function >> + * will fail returning a negative value. >> + */ >> +int request_percpu_nmi(unsigned int irq, irq_handler_t handler, >> + const char *name, void __percpu *dev_id) >> +{ >> + struct irqaction *action; >> + struct irq_desc *desc; >> + unsigned long flags; >> + int retval; >> + >> + if (!handler) >> + return -EINVAL; >> + >> + desc = irq_to_desc(irq); >> + >> + if (!desc || !irq_settings_can_request(desc) >> + || !irq_settings_is_per_cpu_devid(desc) >> + || irq_settings_can_autoenable(desc) >> + || !irq_supports_nmi(desc)) > > Shouldn't the logical operators go at the end of the line in a multi-line > statement? Yes, I'll fix that. > >> + return -EINVAL; >> + >> + /* The line cannot already be NMI */ >> + if (desc->istate & IRQS_NMI) >> + return -EINVAL; >> + >> + action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); >> + if (!action) >> + return -ENOMEM; >> + >> + action->handler = handler; >> + action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD >> + | IRQF_NOBALANCING; > > Shouldn't IRQF_NOBALANCING be aligned with IRQF_PERCPU; > Yes, I'll fix this as well. Thanks, -- Julien Thierry