Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751583Ab1CJInS (ORCPT ); Thu, 10 Mar 2011 03:43:18 -0500 Received: from smtp.ctxuk.citrix.com ([62.200.22.115]:25577 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751050Ab1CJInR (ORCPT ); Thu, 10 Mar 2011 03:43:17 -0500 X-IronPort-AV: E=Sophos;i="4.62,295,1297036800"; d="scan'208";a="4713400" Subject: Re: [Xen-devel] [PATCH 10/14] xen: events: maintain a list of Xen interrupts From: Ian Campbell To: Konrad Rzeszutek Wilk CC: "xen-devel@lists.xensource.com" , "linux-kernel@vger.kernel.org" , "Jeremy Fitzhardinge" , Stefano Stabellini In-Reply-To: <20110310052218.GB10574@dumpdata.com> References: <1299692459.17339.700.camel@zakaz.uk.xensource.com> <1299692486-28634-10-git-send-email-ian.campbell@citrix.com> <20110310052218.GB10574@dumpdata.com> Content-Type: text/plain; charset="UTF-8" Organization: Citrix Systems, Inc. Date: Thu, 10 Mar 2011 08:43:15 +0000 Message-ID: <1299746595.17339.722.camel@zakaz.uk.xensource.com> MIME-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3144 Lines: 89 On Thu, 2011-03-10 at 05:22 +0000, Konrad Rzeszutek Wilk wrote: > On Wed, Mar 09, 2011 at 05:41:22PM +0000, Ian Campbell wrote: > > In a PVHVM kernel not all interrupts are Xen interrupts (APIC interrupts can also be present). > > > > Currently we get away with walking over all interrupts because the > > lookup in the irq_info array simply returns IRQT_UNBOUND and we ignore > > it. However this array will be going away in a future patch so we need > > to manually track which interrupts have been allocated by the Xen > > events infrastructure. > > > > Signed-off-by: Ian Campbell > > --- > > drivers/xen/events.c | 59 +++++++++++++++++++++++++++++++++++++------------ > > 1 files changed, 44 insertions(+), 15 deletions(-) > > > > diff --git a/drivers/xen/events.c b/drivers/xen/events.c > > index cf372d4..e119989 100644 > > --- a/drivers/xen/events.c > > +++ b/drivers/xen/events.c > > @@ -56,6 +56,8 @@ > > */ > > static DEFINE_SPINLOCK(irq_mapping_update_lock); > > > > +static LIST_HEAD(xen_irq_list_head); > > + > > /* IRQ <-> VIRQ mapping. */ > > static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1}; > > > > @@ -85,7 +87,9 @@ enum xen_irq_type { > > */ > > struct irq_info > > { > > + struct list_head list; > > enum xen_irq_type type; /* type */ > > + unsigned irq; > > unsigned short evtchn; /* event channel */ > > unsigned short cpu; /* cpu bound */ > > > > @@ -135,6 +139,7 @@ static void xen_irq_info_common_init(struct irq_info *info, > > BUG_ON(info->type != IRQT_UNBOUND && info->type != type); > > > > info->type = type; > > + info->irq = irq; > > info->evtchn = evtchn; > > info->cpu = cpu; > > > > @@ -311,10 +316,11 @@ static void init_evtchn_cpu_bindings(void) > > { > > int i; > > #ifdef CONFIG_SMP > > - struct irq_desc *desc; > > + struct irq_info *info; > > > > /* By default all event channels notify CPU#0. */ > > - for_each_irq_desc(i, desc) { > > + list_for_each_entry(info, &xen_irq_list_head, list) { > > + struct irq_desc *desc = irq_to_desc(info->irq); > > cpumask_copy(desc->irq_data.affinity, cpumask_of(0)); > > } > > #endif > > @@ -397,6 +403,21 @@ static void unmask_evtchn(int port) > > put_cpu(); > > } > > > > +static void xen_irq_init(unsigned irq) > > +{ > > + struct irq_info *info; > > + struct irq_desc *desc = irq_to_desc(irq); > > + > > + /* By default all event channels notify CPU#0. */ > > + cpumask_copy(desc->irq_data.affinity, cpumask_of(0)); > > + > > + info = &irq_info[irq]; > > + > > + info->type = IRQT_UNBOUND; > > + > > + list_add_tail(&info->list, &xen_irq_list_head); > > Should we use some form of spinlock lock? Just in case > there are two drivers that are being unloaded? The callers are xen_allocate_irq_dynamic and xen_allocate_irq_gsi both of which expect to be protected by irq_mapping_update_lock already. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/