From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gregory Haskins" Subject: Re: [PATCH 3/4] KVM: Adds ability to preempt an executing VCPU Date: Tue, 08 May 2007 08:00:20 -0400 Message-ID: <46402DF3.BA47.005A.0@novell.com> References: <20070502212713.16738.8133.stgit@novell1.haskins.net> <20070502214325.16738.42702.stgit@novell1.haskins.net> <463EF7F4.9020106@qumranet.com> <463F0AC7.BA47.005A.0@novell.com> <4640341E.6090905@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: <4640341E.6090905-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, May 8, 2007 at 4:26 AM, in message <4640341E.6090905-atKUWr5tajBWk0Htik3J/w@public.gmane.org>, Avi Kivity wrote: > Gregory Haskins wrote: >> >>> Hopefully not by setting the >>> signal number, bit by making the vcpu fd writable (userspace can attach >>> a signal to the fd if it wishes). >>> >> >> Can you provide an example of what you would like here? I am not quite sure > what you mean by making the fd writable. >> > > Making it respond to poll(2) as a writable fd. > > See http://lwn.net/Articles/226252/ for an example. It makes the fd > readable instead of writable, but it's the same mechanism. > > The larger picture is that fds and the poll() family are the closest > thing Linux has to a generic event framework. If the patchset in the > article above is accepted, fds _will_ be the generic event framework. > If something else is accepted, we'll just switch to that. > > Qemu currently depends on signals, but you can have a writable fd > generate a signal, and the mechanism for that is optional and > configurable from userspace, which is what we want anyway. Thanks for the link! I will take a look and add this for my next drop. -Greg ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/