From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757446Ab2BICCG (ORCPT ); Wed, 8 Feb 2012 21:02:06 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:49689 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756635Ab2BICCB (ORCPT ); Wed, 8 Feb 2012 21:02:01 -0500 X-Authority-Analysis: v=2.0 cv=T9kOvo2Q c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=UBy9sU4F98IA:10 a=rYfX9MgsDrgA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=VwQbUJbxAAAA:8 a=meVymXHHAAAA:8 a=G5mlRFx8bqFMbdyekpYA:9 a=g6dIRhfFkwH_jhe_7G8A:7 a=Zh68SRI7RUMA:10 a=vC3kRYu6J5IA:10 a=jeBq3FmKZ4MA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-Id: <20120209020159.095037912@goodmis.org> User-Agent: quilt/0.50-1 Date: Wed, 08 Feb 2012 20:59:27 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-rt-users Cc: Thomas Gleixner , Carsten Emde , John Kacur , stable-rt@vger.kernel.org, Lothar Wassmann Subject: [PATCH RT 1/8] genirq: Unmask oneshot irqs when thread was not woken References: <20120209015926.851312665@goodmis.org> Content-Disposition: inline; filename=0001-genirq-Unmask-oneshot-irqs-when-thread-was-not-woken.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner When the primary handler of an interrupt which is marked IRQ_ONESHOT does not wake the thread (e.g. due to a spurious interrupt) then nothing ever unmasks the interrupt line again. Handle it gracefully. Cc: stable-rt@vger.kernel.org Reported-by: Lothar Wassmann Signed-off-by: Thomas Gleixner Signed-off-by: Steven Rostedt --- kernel/irq/chip.c | 25 +++++++++++++++++++++++-- 1 files changed, 23 insertions(+), 2 deletions(-) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index dc5114b..3322a34 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -312,6 +312,24 @@ out_unlock: } EXPORT_SYMBOL_GPL(handle_simple_irq); +/* + * Called unconditionally from handle_level_irq() and only for oneshot + * interrupts from handle_fasteoi_irq() + */ +static void cond_unmask_irq(struct irq_desc *desc) +{ + /* + * We need to unmask in the following cases: + * - Standard level irq (IRQF_ONESHOT is not set) + * - Oneshot irq which did not wake the thread (caused by a + * spurious interrupt or a primary handler handling it + * completely). + */ + if (!irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) + unmask_irq(desc); +} + /** * handle_level_irq - Level type irq handler * @irq: the interrupt number @@ -344,8 +362,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) handle_irq_event(desc); - if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT)) - unmask_irq(desc); + cond_unmask_irq(desc); + out_unlock: raw_spin_unlock(&desc->lock); } @@ -399,6 +417,9 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) preflow_handler(desc); handle_irq_event(desc); + if (desc->istate & IRQS_ONESHOT) + cond_unmask_irq(desc); + out_eoi: desc->irq_data.chip->irq_eoi(&desc->irq_data); out_unlock: -- 1.7.8.3