Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756739Ab3DZQ12 (ORCPT ); Fri, 26 Apr 2013 12:27:28 -0400 Received: from smtp.citrix.com ([66.165.176.89]:10776 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756186Ab3DZQ10 (ORCPT ); Fri, 26 Apr 2013 12:27:26 -0400 X-IronPort-AV: E=Sophos;i="4.87,559,1363132800"; d="scan'208";a="21838434" Date: Fri, 26 Apr 2013 17:27:20 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: Stefano Stabellini , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" Subject: Re: [PATCH 8/9] xen/smp/pvhvm: Don't initialize IRQ_WORKER as we are using the native one. In-Reply-To: <1366142947-18655-9-git-send-email-konrad.wilk@oracle.com> Message-ID: References: <1366142947-18655-1-git-send-email-konrad.wilk@oracle.com> <1366142947-18655-9-git-send-email-konrad.wilk@oracle.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: 2377 Lines: 66 On Tue, 16 Apr 2013, Konrad Rzeszutek Wilk wrote: > There is no need to use the PV version of the IRQ_WORKER mechanism > as under PVHVM we are using the native version. The native > version is using the SMP API. > > They just sit around unused: > > 69: 0 0 xen-percpu-ipi irqwork0 > 83: 0 0 xen-percpu-ipi irqwork1 > > Signed-off-by: Konrad Rzeszutek Wilk Might be worth trying to make it work instead? Is it just because we don't set the apic->send_IPI_* functions to the xen specific version on PVHVM? > arch/x86/xen/smp.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c > index 22c800a..415694c 100644 > --- a/arch/x86/xen/smp.c > +++ b/arch/x86/xen/smp.c > @@ -144,6 +144,13 @@ static int xen_smp_intr_init(unsigned int cpu) > goto fail; > per_cpu(xen_callfuncsingle_irq, cpu) = rc; > > + /* > + * The IRQ worker on PVHVM goes through the native path and uses the > + * IPI mechanism. > + */ > + if (xen_hvm_domain()) > + return 0; > + > callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu); > rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR, > cpu, > @@ -167,6 +174,9 @@ static int xen_smp_intr_init(unsigned int cpu) > if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0) > unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), > NULL); > + if (xen_hvm_domain()) > + return rc; > + > if (per_cpu(xen_irq_work, cpu) >= 0) > unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); > > @@ -661,7 +671,8 @@ static void xen_hvm_cpu_die(unsigned int cpu) > unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL); > unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL); > unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL); > - unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); > + if (!xen_hvm_domain()) > + unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL); > xen_uninit_lock_cpu(cpu); > xen_teardown_timer(cpu); > native_cpu_die(cpu); > -- > 1.8.1.4 > -- 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/