Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759388Ab3DZK1I (ORCPT ); Fri, 26 Apr 2013 06:27:08 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:17465 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751582Ab3DZK1G (ORCPT ); Fri, 26 Apr 2013 06:27:06 -0400 X-IronPort-AV: E=Sophos;i="4.87,557,1363132800"; d="scan'208";a="20734189" Date: Fri, 26 Apr 2013 11:27:00 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Ian Campbell CC: Stefano Stabellini , "xen-devel@lists.xensource.com" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "konrad.wilk@oracle.com" Subject: Re: [PATCH v4 2/7] xen/arm: SMP support In-Reply-To: <1366966304.3142.33.camel@zakaz.uk.xensource.com> Message-ID: References: <1366831695-13214-2-git-send-email-stefano.stabellini@eu.citrix.com> <1366897221.20256.544.camel@zakaz.uk.xensource.com> <1366909184.3142.0.camel@zakaz.uk.xensource.com> <1366966304.3142.33.camel@zakaz.uk.xensource.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1863 Lines: 42 On Fri, 26 Apr 2013, Ian Campbell wrote: > On Thu, 2013-04-25 at 19:45 +0100, Stefano Stabellini wrote: > > On Thu, 25 Apr 2013, Ian Campbell wrote: > > > > > > @@ -216,6 +245,8 @@ static int __init xen_guest_init(void) > > > > > > * is required to use VCPUOP_register_vcpu_info to place vcpu info > > > > > > * for secondary CPUs as they are brought up. */ > > > > > > per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; > > > > > > + for_each_online_cpu(i) > > > > > > + xen_secondary_init(i); > > > > > > > > > > > > gnttab_init(); > > > > > > if (!xen_initial_domain()) > > > > > [...] > > > > > > @@ -244,7 +280,7 @@ static int __init xen_init_events(void) > > > > > > return -EINVAL; > > > > > > } > > > > > > > > > > > > - enable_percpu_irq(xen_events_irq, 0); > > > > > > + on_each_cpu(xen_percpu_enable_events, NULL, 0); > > > > > > > > > > It feels like there ought to be some sort of per-cpu bringup callback > > > > > which takes care of these dynamically. Maybe that doesn't matter until > > > > > we get vcpu hotplug going? > > > > > > > > I suspect there isn't one, considering that on_each_cpu is also used by > > > > kvm_vgic_hyp_init, kvm_timer_hyp_init and others. > > > > > > Could we use cpu_notifiers for this? > > > > cpu_notifiers are for cpu hotplug, not for secondary cpu bringup > > Are you sure they don't also trigger during bringup, because the > distinction is a little bit academic... My mistake, they do run on secondary cpus, but not in our case because xen_guest_init is called *after* cpu_notifiers are called. So, they are too early for Xen. -- 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/