From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH][RFC] KVM: prepare user interface for smp guests Date: Mon, 30 Oct 2006 11:08:32 +0200 Message-ID: <4545C110.8080204@qumranet.com> References: <4544AD24.4040801@qumranet.com> <200610300101.11245.arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-kernel Return-path: To: Arnd Bergmann In-Reply-To: <200610300101.11245.arnd-r2nGTMty4D4@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 Arnd Bergmann wrote: > Separating the objects into different file descriptors sounds like a > good idea, but reusing an open dentry/inode with a new file and different > file operations is a rather unusual way to do it. Yes, it doesn't feel right. > Your concept of allocating > a new context on each open is already weird, but there have been other > examples of that before. > Actually that seemed to me quite natural. > I'd suggest going to a syscall-based model with your own file system right > away, even if you don't use the spufs approach but something in the middle: > > * You do a trivial nonmountable new file system with anonymous objects, > similar to eventpollfs, and hand out file descriptors to inodes in it, > for both the kvm and the vcpu objects. > * You replace the syscall you'd normally use to hand out a new kvm instance > with an ioctl on /dev/kvm, and don't allow any other operations on that > device. > > This would be a much more consistant object model, compared with other > generic kernel functionality that is not bound to an actual device. > You still have all the flexibility of a loadable module without core > kernel changes for the development phase, and can easily switch to real > syscalls when merging it into mainline. > I agree, that sounds like a good plan. I'll look into it. BTW, what does lsof show for spufs users? I thought lsof /dev/kvm would be a good way to look for virtual machines. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642