From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751405AbXBMX0G (ORCPT ); Tue, 13 Feb 2007 18:26:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751406AbXBMX0G (ORCPT ); Tue, 13 Feb 2007 18:26:06 -0500 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:33146 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751405AbXBMX0F (ORCPT ); Tue, 13 Feb 2007 18:26:05 -0500 X-Greylist: delayed 1909 seconds by postgrey-1.27 at vger.kernel.org; Tue, 13 Feb 2007 18:26:05 EST Message-ID: <45D24172.9020800@vmware.com> Date: Tue, 13 Feb 2007 14:53:38 -0800 From: Dan Hecht User-Agent: Thunderbird 1.5.0.2 (X11/20060420) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Andi Kleen , Andrew Morton , virtualization@lists.osdl.org, xen-devel@lists.xensource.com, Chris Wright , Ian Pratt , linux-kernel@vger.kernel.org Subject: Re: [patch 14/21] Xen-paravirt: Add XEN config options and disable unsupported config options. References: <20070213221729.772002682@goop.org> <20070213221830.542511707@goop.org> In-Reply-To: <20070213221830.542511707@goop.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 13 Feb 2007 22:54:10.0245 (UTC) FILETIME=[DFA03750:01C74FC1] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 02/13/2007 02:17 PM, Jeremy Fitzhardinge wrote: > The XEN config option enables the Xen paravirt_ops interface, which is > installed when the kernel finds itself running under Xen. (By some > as-yet fully defined mechanism, implemented in a future patch.) > > Xen is no longer a sub-architecture, so the X86_XEN subarch config > option has gone. > > The disabled config options are: > - PREEMPT: Xen doesn't support it > - HZ: set to 100Hz for now, to cut down on VCPU context switch rate. > This will be adapted to use tickless later. > - kexec: not yet supported > I assume you plan to eventually get all this stuff working but just want to prevent configurations that the Xen paravirt-ops isn't ready for at the moment? Instead can you do it this way: config XEN depends on PARAVIRT && !PREEMPT && HZ_100 && !DOUBLEFAULT && !KEXEC thanks, Dan > Signed-off-by: Jeremy Fitzhardinge > Signed-off-by: Ian Pratt > Signed-off-by: Christian Limpach > Signed-off-by: Chris Wright > > --- > arch/i386/Kconfig | 7 +++++-- > arch/i386/Kconfig.debug | 1 + > arch/i386/xen/Kconfig | 10 ++++++++++ > kernel/Kconfig.hz | 4 ++-- > kernel/Kconfig.preempt | 1 + > 5 files changed, 19 insertions(+), 4 deletions(-) > > =================================================================== > --- a/arch/i386/Kconfig > +++ b/arch/i386/Kconfig > @@ -192,6 +192,8 @@ config PARAVIRT > under a hypervisor, improving performance significantly. > However, when run without a hypervisor the kernel is > theoretically slower. If in doubt, say N. > + > +source "arch/i386/xen/Kconfig" > > config ACPI_SRAT > bool > @@ -298,12 +300,12 @@ config X86_UP_IOAPIC > > config X86_LOCAL_APIC > bool > - depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH > + depends on X86_UP_APIC || (((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH) > default y > > config X86_IO_APIC > bool > - depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH > + depends on X86_UP_IOAPIC || ((SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH) > default y > > config X86_VISWS_APIC > @@ -743,6 +745,7 @@ source kernel/Kconfig.hz > > config KEXEC > bool "kexec system call" > + depends on !XEN > help > kexec is a system call that implements the ability to shutdown your > current kernel, and to start another kernel. It is like a reboot > =================================================================== > --- a/arch/i386/Kconfig.debug > +++ b/arch/i386/Kconfig.debug > @@ -79,6 +79,7 @@ config DOUBLEFAULT > config DOUBLEFAULT > default y > bool "Enable doublefault exception handler" if EMBEDDED > + depends on !XEN > help > This option allows trapping of rare doublefault exceptions that > would otherwise cause a system to silently reboot. Disabling this > =================================================================== > --- /dev/null > +++ b/arch/i386/xen/Kconfig > @@ -0,0 +1,10 @@ > +# > +# This Kconfig describes xen options > +# > + > +config XEN > + bool "Enable support for Xen hypervisor" > + depends PARAVIRT > + default y > + help > + This is the Linux Xen port. > =================================================================== > --- a/kernel/Kconfig.hz > +++ b/kernel/Kconfig.hz > @@ -3,7 +3,7 @@ > # > > choice > - prompt "Timer frequency" > + prompt "Timer frequency" if !XEN > default HZ_250 > help > Allows the configuration of the timer frequency. It is customary > @@ -49,7 +49,7 @@ endchoice > > config HZ > int > - default 100 if HZ_100 > + default 100 if HZ_100 || XEN > default 250 if HZ_250 > default 300 if HZ_300 > default 1000 if HZ_1000 > =================================================================== > --- a/kernel/Kconfig.preempt > +++ b/kernel/Kconfig.preempt > @@ -35,6 +35,7 @@ config PREEMPT_VOLUNTARY > > config PREEMPT > bool "Preemptible Kernel (Low-Latency Desktop)" > + depends on !XEN > help > This option reduces the latency of the kernel by making > all kernel code (that is not executing in a critical section) >