From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: [RFC] Pass-through Interdomain Interrupts Sharing (HVM/Dom0) Date: Fri, 10 Aug 2007 12:21:47 +0100 Message-ID: References: <9392A06CB0FDC847B3A530B3DC174E7B0327D082@mse10be1.mse10.exchange.ms> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <9392A06CB0FDC847B3A530B3DC174E7B0327D082@mse10be1.mse10.exchange.ms> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Guy Zana , xen-devel@lists.xensource.com Cc: Alex Novik List-Id: xen-devel@lists.xenproject.org On 10/8/07 11:22, "Guy Zana" wrote: >> My thought here is a simple priority list with move-to-back >> of the frontmost domain when we deliver him the interrupt but >> he does not deassert the line either in reasonable time or by >> the time he EOIs the interrupt. This is simple generic logic >> needing no PV guest changes. > > Even if the HVM handled the interrupt successfully, it doesn't mean that the > pline will be deasserted (if another device assigned to another domain > asserted it while the HVM processed the interrupt).You can't tell whether the > HVM handled the interrupt successfully or not. How this method overcome this? It would cycle through the priority list, moving frontmost to back at each stage, until the line is deasserted. > Btw, with the method we proposed you could add PV domains to the interdomain > ISR chain, but it may not contain more than one HVM. Well, that kind of sucks doesn't it. And yet your method is significantly more complicated than my approach, at least as described in your email. Simple and more general wins the day, unless your approach handles more cases or has better performance? -- Keir