From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NHf03-0006hf-Lt for qemu-devel@nongnu.org; Mon, 07 Dec 2009 09:55:43 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NHezx-0006aa-8y for qemu-devel@nongnu.org; Mon, 07 Dec 2009 09:55:42 -0500 Received: from [199.232.76.173] (port=54603 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NHezw-0006a2-Ll for qemu-devel@nongnu.org; Mon, 07 Dec 2009 09:55:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53010) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NHebP-0003C4-Ex for qemu-devel@nongnu.org; Mon, 07 Dec 2009 09:30:15 -0500 Message-ID: <4B1D1171.1000701@redhat.com> Date: Mon, 07 Dec 2009 15:30:09 +0100 From: Gerd Hoffmann MIME-Version: 1.0 References: <1259137008-9669-1-git-send-email-kraxel@redhat.com> <1259137008-9669-2-git-send-email-kraxel@redhat.com> <20091207093716.GA31370@redhat.com> <4B1CD9C4.4020509@redhat.com> <20091207105950.GA3376@redhat.com> <4B1CE5D2.5080205@redhat.com> <20091207130329.GA3937@redhat.com> <4B1D0031.20705@redhat.com> <20091207141339.GC5328@redhat.com> In-Reply-To: <20091207141339.GC5328@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH 2/2] virtio: enable msi-x for console+balloon List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel@nongnu.org On 12/07/09 15:13, Michael S. Tsirkin wrote: > Gerd, any idea whether "one MSI-X vector" feature is worth pursuing? I'd rate it low priority. First because virtio-enabled guests can use virtio-net+blk. Also because with the upcoming p35 support we'll get a more modern pc emulation including a ioapic with all 24 IRQ lines being wired up, which will help reducing IRQ sharing too. MSI support (no -X) could be more intresting (for emulated devices) as it is older and thus support is more common. My T60 for example has no device with MSI-X support but 9 with MSI support. Linux turns on MSI for 7 of them (4 PCIe ports, e1000, ahci, iwl3945). cheers, Gerd