From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gregory Haskins" Subject: Re: [PATCH] Support for in-kernel mmio handlers Date: Tue, 10 Apr 2007 07:49:25 -0400 Message-ID: <461B4176.BA47.005A.0@novell.com> References: <4613C73F.BA47.005A.0@novell.com> <4614A03C.2050707@qumranet.com> <4614C844.BA47.005A.0@novell.com> <4618AC94.3040700@qumranet.com> <461A03F3.BA47.005A.0@novell.com> <461B4319.80608@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: "Avi Kivity" Return-path: In-Reply-To: <461B4319.80608-atKUWr5tajBWk0Htik3J/w@public.gmane.org> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org >>> On Tue, Apr 10, 2007 at 3:56 AM, in message <461B4319.80608-atKUWr5tajBWk0Htik3J/w@public.gmane.org>, Avi Kivity wrote: > Gregory Haskins wrote: >> >> Note that I finally understand what you were getting at with the array of > objects thing. I didn't change it yet for the same reason that you > mentioned: reduction of churn. However, now that I understand it, I see why > you wanted it. Perhaps I will send a follow- on to this patch that uses your > idea. But for now... >> > > I will try to be more explicit in the future. > Nah, I think you explained it fine, I was just being too obtuse ;) When you first brought it up, I figured there was some secret deficiency in the linked-list implementation compared to arrays that I wasn't aware of and didn't question it. I see now that what you were getting at is that an array of objects with the range criteria in-line can be made to fit in a handful of cache-lines. Having an indirection to find the kvm_io_device* and another to find the in_range() function do not have this benefit (which both the list and the pointer-array as I have implemented suffer from this). >> --- >> >> KVM: Add support for in- kernel mmio handlers >> >> There is a near- term need for moving some of the emulation from userspace to >> the kernel (e.g. interrupt handling). This patch adds a construct for >> registering in- kernel MMIO handlers. The consumers of this interface will >> appear in a follow- on patch. >> > > > Given that the first consumer is the local apic, it makes sense to add > the vcpu- local bus first, no? I'm confused. I thought you didn't like the vpcu-local bus? I pulled it based on your feedback :) Please advise. Regards, -Greg ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV