From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59048) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZZsvf-0007Mr-Gr for qemu-devel@nongnu.org; Wed, 09 Sep 2015 23:53:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZZsvc-0006Ne-9s for qemu-devel@nongnu.org; Wed, 09 Sep 2015 23:53:43 -0400 Received: from mga02.intel.com ([134.134.136.20]:33938) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZZsvb-0006NL-VW for qemu-devel@nongnu.org; Wed, 09 Sep 2015 23:53:40 -0400 Date: Thu, 10 Sep 2015 11:57:02 +0800 From: Yuanhan Liu Message-ID: <20150910035702.GP2925@yliu-dev.sh.intel.com> References: <1441697927-16456-1-git-send-email-yuanhan.liu@linux.intel.com> <1441697927-16456-6-git-send-email-yuanhan.liu@linux.intel.com> <55F0F593.9030408@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <55F0F593.9030408@redhat.com> Subject: Re: [Qemu-devel] [PATCH 5/7] vhost_net: move vhost_net_set_vq_index ahead at vhost_net_init List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Wang Cc: mst@redhat.com, qemu-devel@nongnu.org, changchun.ouyang@intel.com On Thu, Sep 10, 2015 at 11:14:27AM +0800, Jason Wang wrote: > > > On 09/08/2015 03:38 PM, Yuanhan Liu wrote: > > So that we could use the `vq_index' as well in the vhost_net_init > > stage, which is required when adding vhost-user multiple-queue support, > > where we need the vq_index to indicate which queue pair we are gonna > > initiate. > > > > vhost-user has no multiple queue support yet, hence no queue_index set > > before. Here is a quick set to 0 at net_vhost_user_init() stage, and it > > will be set properly soon in the next patch. > > > > Signed-off-by: Yuanhan Liu > > --- > > hw/net/vhost_net.c | 16 +++++++--------- > > net/vhost-user.c | 1 + > > 2 files changed, 8 insertions(+), 9 deletions(-) > > > > diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c > > index f9441e9..141b557 100644 > > --- a/hw/net/vhost_net.c > > +++ b/hw/net/vhost_net.c > > @@ -138,6 +138,11 @@ static int vhost_net_get_fd(NetClientState *backend) > > } > > } > > > > +static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index) > > +{ > > + net->dev.vq_index = vq_index; > > +} > > + > > struct vhost_net *vhost_net_init(VhostNetOptions *options) > > { > > int r; > > @@ -167,6 +172,8 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options) > > } > > net->nc = options->net_backend; > > > > + vhost_net_set_vq_index(net, net->nc->queue_index * 2); > > + > > This breaks vhost kernel multiqueue since queue_index was not > initialized at this time. Right, thanks for pointing it out. > We do this in set_netdev() instead of setting > it in each kind of netdev. Can we move it to net_init_tap() for setting the right queue_index for each nc? Or, can we call vhost_net_set_vq_index twice, one at vhost_net_init(for vhost-user mq support), another one at vhost_net_start(for vhost kernel mq support)? Or, do you have better ideas? > > > net->dev.nvqs = 2; > > net->dev.vqs = net->vqs; > > > > @@ -196,11 +203,6 @@ fail: > > return NULL; > > } > > > > -static void vhost_net_set_vq_index(struct vhost_net *net, int vq_index) > > -{ > > - net->dev.vq_index = vq_index; > > -} > > - > > static int vhost_net_set_vnet_endian(VirtIODevice *dev, NetClientState *peer, > > bool set) > > { > > @@ -325,10 +327,6 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs, > > goto err; > > } > > > > - for (i = 0; i < total_queues; i++) { > > - vhost_net_set_vq_index(get_vhost_net(ncs[i].peer), i * 2); > > - } > > - > > r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true); > > if (r < 0) { > > error_report("Error binding guest notifier: %d", -r); > > diff --git a/net/vhost-user.c b/net/vhost-user.c > > index 93dcecd..2d6bbe5 100644 > > --- a/net/vhost-user.c > > +++ b/net/vhost-user.c > > @@ -146,6 +146,7 @@ static int net_vhost_user_init(NetClientState *peer, const char *device, > > /* We don't provide a receive callback */ > > s->nc.receive_disabled = 1; > > s->chr = chr; > > + nc->queue_index = 0; > > > > Fail to understand why this is needed. It will be set to correct value > in set_netdev(). Right, it's unnecessary. BTW, May I ask you a quick question: why set_netdev is invoked after tap init, while it is invoked before vhost-user init? --yliu > > > qemu_chr_add_handlers(s->chr, NULL, NULL, net_vhost_user_event, s); > >