Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754706Ab2KSSoa (ORCPT ); Mon, 19 Nov 2012 13:44:30 -0500 Received: from webmail.solarflare.com ([12.187.104.25]:32588 "EHLO webmail.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754074Ab2KSSo2 (ORCPT ); Mon, 19 Nov 2012 13:44:28 -0500 Message-ID: <1353350661.4156.0.camel@bwh-desktop.uk.solarflarecom.com> Subject: Re: [rfc net-next v6 2/3] virtio_net: multiqueue support From: Ben Hutchings To: "Michael S. Tsirkin" CC: Rusty Russell , Jason Wang , , , , , , , Date: Mon, 19 Nov 2012 18:44:21 +0000 In-Reply-To: <20121118091354.GA31775@redhat.com> References: <1351591403-23065-1-git-send-email-jasowang@redhat.com> <1351591403-23065-3-git-send-email-jasowang@redhat.com> <87y5igyhyg.fsf@rustcorp.com.au> <20121113064026.GA27416@redhat.com> <1353112529.2743.83.camel@bwh-desktop.uk.solarflarecom.com> <20121118091354.GA31775@redhat.com> Organization: Solarflare Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 (3.2.3-3.fc16) Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-Originating-IP: [10.17.20.137] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2313 Lines: 56 On Sun, 2012-11-18 at 11:13 +0200, Michael S. Tsirkin wrote: > On Sat, Nov 17, 2012 at 12:35:29AM +0000, Ben Hutchings wrote: > > On Tue, 2012-11-13 at 08:40 +0200, Michael S. Tsirkin wrote: > > > On Mon, Nov 05, 2012 at 11:38:39AM +1030, Rusty Russell wrote: > > > > > @@ -924,11 +1032,10 @@ static void virtnet_get_ringparam(struct net_device *dev, > > > > > { > > > > > struct virtnet_info *vi = netdev_priv(dev); > > > > > > > > > > - ring->rx_max_pending = virtqueue_get_vring_size(vi->rvq); > > > > > - ring->tx_max_pending = virtqueue_get_vring_size(vi->svq); > > > > > + ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq); > > > > > + ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq); > > > > > ring->rx_pending = ring->rx_max_pending; > > > > > ring->tx_pending = ring->tx_max_pending; > > > > > - > > > > > } > > > > > > > > This assumes all vqs are the same size. I think this should probably > > > > check: for mq mode, use the first vq, otherewise use the 0th. > > > > > > For rx_pending/tx_pending I think what is required here is the > > > actual number of outstanding buffers. > > > Dave, Eric - right? > > > > > > So this should be the total over all rings and to be useful, > > > rx_max_pending/tx_max_pending should be the total too. > > > > So far as I know, all current implementations use the number of > > descriptors per ring here. virtio_net should be consistent with this. > > > > Ben. > > Problem is, it could in theory be different between rings. I guess we > could use the maximum. > > What's the right thing to do for rx_pending - I am guessing > we want the current outstanding packets right? The 'max_pending' fields are for the maximum ring sizes supported; the 'pending' fields are for the current ring sizes. The current number of descriptors pending is not included (would be a bit pointless). Ben. -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/