Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752257Ab1CJFXh (ORCPT ); Thu, 10 Mar 2011 00:23:37 -0500 Received: from rcsinet10.oracle.com ([148.87.113.121]:63095 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751980Ab1CJFXT (ORCPT >); Thu, 10 Mar 2011 00:23:19 -0500 Date: Thu, 10 Mar 2011 00:22:18 -0500 From: Konrad Rzeszutek Wilk To: Ian Campbell Cc: xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org, Jeremy Fitzhardinge , Stefano Stabellini Subject: Re: [Xen-devel] [PATCH 10/14] xen: events: maintain a list of Xen interrupts Message-ID: <20110310052218.GB10574@dumpdata.com> References: <1299692459.17339.700.camel@zakaz.uk.xensource.com> <1299692486-28634-10-git-send-email-ian.campbell@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1299692486-28634-10-git-send-email-ian.campbell@citrix.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Source-IP: acsmt353.oracle.com [141.146.40.153] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090206.4D78603F.00BF,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2781 Lines: 84 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? -- 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/