Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946054AbXBPVvX (ORCPT ); Fri, 16 Feb 2007 16:51:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1946074AbXBPVvX (ORCPT ); Fri, 16 Feb 2007 16:51:23 -0500 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:40864 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946054AbXBPVvW (ORCPT ); Fri, 16 Feb 2007 16:51:22 -0500 Message-ID: <45D62759.7080006@vmware.com> Date: Fri, 16 Feb 2007 13:51:21 -0800 From: Zachary Amsden User-Agent: Thunderbird 1.5.0.9 (X11/20061206) MIME-Version: 1.0 To: Keir Fraser CC: Jeremy Fitzhardinge , xen-devel@lists.xensource.com, virtualization@lists.osdl.org, Steven Hand , linux-kernel@vger.kernel.org, Chris Wright , Andi Kleen , Andrew Morton , Ian Pratt , Christian Limpach Subject: Re: [Xen-devel] Re: [patch 14/21] Xen-paravirt: Add XEN config options and disableunsupported config options. References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1476 Lines: 34 Keir Fraser wrote: > On 16/2/07 17:46, "Jeremy Fitzhardinge" wrote: > > >> Keir Fraser wrote: >> >>> This initial patchset does not include save/restore support anyway, so in >>> fact it would be consistent to have CONFIG_PREEMPT configurable. I'm sure >>> that we are going to have some nasty bugs to fix up as a result, but we >>> can't fix them until we find them! Then we can convert our save/restore code >>> to use the freezer before submitting it for inclusion. >>> >> OK. So that makes the only config restriction the 100Hz ticks. >> > > We can extend the Xen timer interface quite easily and get rid of this one > too. In fact it doesn't *much* matter if the CONFIG_HZ differs from the Xen > ticker rate -- we modified the Linux timer ISR to handle timer interrupts at > arbitrary times already. The only drawback is that jiffies updates in burts > if CONFIG_HZ is higher than the actual tick rate, and this can affect some > calibration constants and cause Linux to print out some weird values at > start-of-day. > That's why we'd very much like to get a get_cpu_speed paravirt-op implemented. I think this would be useful to work around these problems for Xen as well. Zach - 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/