From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC] KVM Source layout Proposal to accommodate new CPU architecture Date: Thu, 27 Sep 2007 11:18:30 +0200 Message-ID: <46FB7566.9030504@qumranet.com> References: <42DFA526FC41B1429CE7279EF83C6BDC753A4E@pdsmsx415.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, virtualization To: "Zhang, Xiantao" Return-path: In-Reply-To: <42DFA526FC41B1429CE7279EF83C6BDC753A4E-wq7ZOvIWXbMAbVU2wMM1CrfspsVTdybXVpNB7YpNyf8@public.gmane.org> 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 Zhang, Xiantao wrote: > Hi Folks, > We are working on enabling KVM support on IA64 platform, and now > Linux, Windows guests get stable run and achieve reasonable performance > on KVM with Open GFW. But you know, the current KVM only considers x86 > platform, and is short of cross-architecture framework. Currently, we > have a proposal for KVM source layout to accommodate new CPU > architectures. Attached foil describes the detail. With our proposal, we > can boot x86 guests based on commit > 2e278972a11eb14f031dea242a9ed118adfa0932, also didn't see regressions. > For IA64 side, we are rebasing our code to this framework. > Main changes to current source: > 1. Add subdirectories, such as x86 and ia64 to hold arch-specific code. > 2. Split kvm_main.c to two parts. One is still called kvm_main.c, just > contains KVM common interfaces with user space, and basic KVM > infrastructure. The other one is named as kvm_arch.c under sub-directory > (eg. X86, ia64 etc), which includes arch-specific code to supplement the > functionality of kvm_main.c > 3. Add an "include" directory in drivers/kvm. Due to possibly complex > code logic in KVM source, maybe many header files need to maintain for > some architectures. If we put them under top-level include/asm-arch > directory, it may introduce much more maintain effort. So, we put it > under "drivers/kvm", and let it be effective when kernel configuration > time. > BTW, Userspace code changes are not involved in this thread. > Considering the readability, we didn't attach the diff file in the mail, > due to big changes to kvm source structure, and only post the tarball > including whole directory "drivers/kvm" instead. For comparison, I > attached kvm_main.diff as well. > > Any comments are appreciated from you! Hope to see IA64 support on KVM > earlier! > The whole drivers/kvm/ thing was just a trick to get merged quickly. I think the new layout should be something like virt/kvm/, include/linux/kvm*.h -> common code virt/lguest/ -> the other hypervisor virt/virtio/ -> shared I/O infrastructure virt/ -> the CONFIG_VIRTIALIZATION menu arch/x86/kvm/, include/asm-x86/ -> x86 specific code arch/ia64/kvm/, include/asm-ia64/ -> ia64 specific code etc. Of course, this depends on the x86 merge which is scheduled for early 2.6.24. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/