From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757724Ab2FFRw1 (ORCPT ); Wed, 6 Jun 2012 13:52:27 -0400 Received: from mga14.intel.com ([143.182.124.37]:63532 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752667Ab2FFRwZ convert rfc822-to-8bit (ORCPT ); Wed, 6 Jun 2012 13:52:25 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="152460033" From: "Iyer, Sundar" To: "tglx@linutronix.de" CC: "linux-kernel@vger.kernel.org" , "lethal@linux-sh.org" , "arjan@linux.intel.com" , "Monroy, German" Subject: RE: [PATCH v2] x86/irq: handle chained interrupts during IRQ migration Thread-Topic: [PATCH v2] x86/irq: handle chained interrupts during IRQ migration Thread-Index: AQHNPkQDApkIwRsebESeNTDprZRGRpbtnVkQ Date: Wed, 6 Jun 2012 17:52:21 +0000 Message-ID: <2FABAEF0D3DCAF4F9C9628D6E2F968451D8329@BGSMSX102.gar.corp.intel.com> References: <1338370137-18929-1-git-send-email-sundar.iyer@intel.com> In-Reply-To: <1338370137-18929-1-git-send-email-sundar.iyer@intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.223.10.10] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, Any comments on this version? Or do you suggest to add a new flag in the accessors and set it? Thanks >-----Original Message----- >From: Iyer, Sundar >Sent: Wednesday, May 30, 2012 2:59 PM >To: tglx@linutronix.de >Cc: linux-kernel@vger.kernel.org; lethal@linux-sh.org; arjan@linux.intel.com; Iyer, >Sundar; Monroy, German >Subject: [PATCH v2] x86/irq: handle chained interrupts during IRQ migration > >Chained interrupt handlers dont have an irqaction and hence are not handled during >migrating interrupts when some cores go offline. > >Handle this by introducing a irq_is_chained() check which is based on the the very least >NOREQUEST, NOPROBE, and NOTHREAD flags being set for such interrupts. >fixup_irq() can then handle such interrupts and not skip them over. > >Change-Id: I011de8bee98c1702a362deb06106845ca7bcad61 >Signed-off-by: Sundar Iyer >--- >v1: use accessors instead of new variables to identify chained irqs >v2: use a mask of NOREQUEST, NOPROBE, and NOTHREAD accessor flags as per >Paul M > > arch/x86/kernel/irq.c | 6 ++++-- > include/linux/irqdesc.h | 11 +++++++++++ > 2 files changed, 15 insertions(+), 2 deletions(-) > >diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c index 6c0802e..acd7949 100644 >--- a/arch/x86/kernel/irq.c >+++ b/arch/x86/kernel/irq.c >@@ -249,8 +249,10 @@ void fixup_irqs(void) > > data = irq_desc_get_irq_data(desc); > affinity = data->affinity; >- if (!irq_has_action(irq) || irqd_is_per_cpu(data) || >- cpumask_subset(affinity, cpu_online_mask)) { >+ /* include IRQs who have no action, but are chained */ >+ if ((!irq_has_action(irq) && irq_is_chained(irq)) || >+ irqd_is_per_cpu(data) || >+ cpumask_subset(affinity, cpu_online_mask)) { > raw_spin_unlock(&desc->lock); > continue; > } >diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h index 2d921b3..8d5eb42 >100644 >--- a/include/linux/irqdesc.h >+++ b/include/linux/irqdesc.h >@@ -120,6 +120,17 @@ static inline int irq_has_action(unsigned int irq) > return desc->action != NULL; > } > >+/* >+ * Test to see if the IRQ is chained; it would not be requested and >+hence >+ * very miinimum _IRQ_NOREQUEST, _IRQ_NOPROBE, _IRQ_NOTHREAD would be >+set */ static inline int irq_is_chained(unsigned int irq) { >+ struct irq_desc *desc = irq_to_desc(irq); >+ return !(desc->status_use_accessors & >+ (IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOTHREAD)); } >+ > /* caller has locked the irq_desc and both params are valid */ static inline void >__irq_set_handler_locked(unsigned int irq, > irq_flow_handler_t handler) >-- >1.7.1