From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [RFC][PATCH 1/2] kvm: Introduce basic MSI support in-kernel irqchips Date: Wed, 28 Mar 2012 13:09:25 +0200 Message-ID: <4F72F165.8020009@redhat.com> References: <865ef757142e5b9a670dfc9bcd8eb0ff7ab5d58b.1332371825.git.jan.kiszka@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org, qemu-devel , "Michael S. Tsirkin" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:27279 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757736Ab2C1LJa (ORCPT ); Wed, 28 Mar 2012 07:09:30 -0400 In-Reply-To: <865ef757142e5b9a670dfc9bcd8eb0ff7ab5d58b.1332371825.git.jan.kiszka@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On 03/22/2012 01:17 AM, Jan Kiszka wrote: > From: Jan Kiszka > > This patch basically adds kvm_irqchip_send_msi, a service for sending > arbitrary MSI messages to KVM's in-kernel irqchip models. > > As the current KVI API requires us to establish a static route from a s/KVI/KVM/ > pseudo GSI to the target MSI message and inject the MSI via toggling > that GSI, we need to play some tricks to make this unfortunately s/unfortunately/unfortunate/ > interface transparent. We create those routes on demand and keep them > in a hash table. Succeeding messages can then search for an existing > route in the table first and reuse it whenever possible. If we should > run out of limited GSIs, we simply flush the table and rebuild it as > messages are sent. > > This approach is rather simple and could be optimized further. However, > it is more efficient to enhance the KVM API so that we do not need this > clumsy dynamic routing over futures kernels. Two APIs are clumsier than one. wet the patch itself, suggest replacing the home grown hash with http://developer.gnome.org/glib/2.30/glib-Caches.html. -- error compiling committee.c: too many arguments to function