From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48421) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c9mHt-0000HG-OH for qemu-devel@nongnu.org; Thu, 24 Nov 2016 00:09:34 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c9mHo-00009e-P5 for qemu-devel@nongnu.org; Thu, 24 Nov 2016 00:09:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:36490) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1c9mHo-00007h-JM for qemu-devel@nongnu.org; Thu, 24 Nov 2016 00:09:28 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 665A181235 for ; Thu, 24 Nov 2016 05:09:27 +0000 (UTC) Date: Thu, 24 Nov 2016 07:09:26 +0200 From: "Michael S. Tsirkin" Message-ID: <20161124070716-mutt-send-email-mst@kernel.org> References: <1477935706-4250-1-git-send-email-wexu@redhat.com> <1477935706-4250-2-git-send-email-wexu@redhat.com> <69ada11c-c401-b85a-66bc-78d3a0b82e2c@redhat.com> <20161124062419-mutt-send-email-mst@kernel.org> <78ce0060-9b7c-876d-22de-dd71af7df76e@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <78ce0060-9b7c-876d-22de-dd71af7df76e@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 1/2] virtio-net rsc: support coalescing ipv4 tcp traffic List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang Cc: wexu@redhat.com, qemu-devel@nongnu.org, dfleytma@redhat.com, yvugenfi@redhat.com On Thu, Nov 24, 2016 at 12:31:18PM +0800, Jason Wang wrote: >=20 >=20 > On 2016=E5=B9=B411=E6=9C=8824=E6=97=A5 12:26, Michael S. Tsirkin wrote: > > On Thu, Nov 24, 2016 at 12:17:21PM +0800, Jason Wang wrote: > > > > diff --git a/include/standard-headers/linux/virtio_net.h b/includ= e/standard-headers/linux/virtio_net.h > > > > index 30ff249..e67b36e 100644 > > > > --- a/include/standard-headers/linux/virtio_net.h > > > > +++ b/include/standard-headers/linux/virtio_net.h > > > > @@ -57,6 +57,9 @@ > > > > * Steering */ > > > > #define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */ > > > > +/* Guest can handle coalesced ipv4-tcp packets */ > > > > +#define VIRTIO_NET_F_GUEST_RSC4 41 > > > Why not use 24? > > I think we should use features >31 (virtio 1 only) for > > nice-to-have features like RSC. Feature bits <31 are > > easy to backport, so it makes more sense to use > > them for fundamental things like the MTU > > (which for some setups help fix broken networking). >=20 > Ok, I believe we need clarify this in the spec or somewhere else. There is a design considerations chapter, it can go there. --=20 MST