From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MgZrX-0001Be-M8 for qemu-devel@nongnu.org; Thu, 27 Aug 2009 03:57:39 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MgZrT-00019z-Sp for qemu-devel@nongnu.org; Thu, 27 Aug 2009 03:57:39 -0400 Received: from [199.232.76.173] (port=46985 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MgZrT-00019u-N5 for qemu-devel@nongnu.org; Thu, 27 Aug 2009 03:57:35 -0400 Received: from mx20.gnu.org ([199.232.41.8]:18988) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1MgZrT-0002tU-6Z for qemu-devel@nongnu.org; Thu, 27 Aug 2009 03:57:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]) by mx20.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MgZrS-0005SQ-4n for qemu-devel@nongnu.org; Thu, 27 Aug 2009 03:57:34 -0400 Message-ID: <4A963C66.6040300@redhat.com> Date: Thu, 27 Aug 2009 10:57:26 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH 2/2] Route IOAPIC interrupts via ISA bus References: <1249836296-13288-1-git-send-email-avi@redhat.com> <1249836296-13288-3-git-send-email-avi@redhat.com> <4A955CB4.4080205@redhat.com> <4A955D6A.9060804@redhat.com> <4A95633E.7060703@redhat.com> <4A961161.5030906@redhat.com> <4A96375D.1070005@redhat.com> In-Reply-To: <4A96375D.1070005@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: qemu-devel@nongnu.org On 08/27/2009 10:35 AM, Gerd Hoffmann wrote: >>> BTW: Seems linux doesn't use IRQ 5 even with lots of PCI devices, >>> instead it makes them share 10+11 ... >> >> We could change the defaults to include 5, but maybe it makes more sense >> to fix Linux to distribute active PCI IRQs across the resources it has >> at its disposal. > > i.e. Linux decides to stick with the defaults (starred) here ... > > ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] > ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11) > ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11) > ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11) > ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11) > > ... instead of trying to minimize IRQ sharing by using IRQ 5? Yes. And if it turns out you have two active devices and 6 inactive devices, move the two active devices to private lines and pile up the inactive ones on the leftover. > >> They'll be slow regardless. I should be easy to support msi on e1000 >> though. > > What is needed on the guest side? Looks like even 2.6.30 doesn't use > MSI for virtio-net ... virtio msi support was merged in 2.6.31. For e1000, guest support is presumably there, just need to wire it into the device. -- error compiling committee.c: too many arguments to function