| Message ID | 20120404091954.GA3776@redhat.com |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On (Wed) 04 Apr 2012 [12:19:55], Michael S. Tsirkin wrote: > disable_cb is just an optimization: it > can not guarantee that there are no callbacks. Even then, what's the harm in keeping it? If indeed there's an attempt to raise an interrupt after the host has been notified, it will be suppressed. Also, disable_cb seems to be used elsewhere in the virtio_net.c file, to suit similar purposes. Amit -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 03, 2012 at 04:29:59PM +0530, Amit Shah wrote: > On (Wed) 04 Apr 2012 [12:19:55], Michael S. Tsirkin wrote: > > disable_cb is just an optimization: it > > can not guarantee that there are no callbacks. > > Even then, what's the harm in keeping it? If indeed there's an > attempt to raise an interrupt after the host has been notified, it > will be suppressed. It won't. It's not a guarantee, e.g. with event index on it does nothing at all. > Also, disable_cb seems to be used elsewhere in the virtio_net.c file, > to suit similar purposes. > > Amit Where? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Apr 04, 2012 at 12:19:54PM +0300, Michael S. Tsirkin wrote: > disable_cb is just an optimization: it > can not guarantee that there are no callbacks. > > I didn't yet figure out whether a callback > in freeze will trigger a bug, but disable_cb > won't address it in any case. So let's remove > the useless calls as a first step. > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Looks like this isn't in the 3.5 pull request - just lost in the shuffle? disable_cb is advisory so can't be relied upon. > --- > drivers/net/virtio_net.c | 5 ----- > 1 files changed, 0 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 019da01..971931e5 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1182,11 +1182,6 @@ static int virtnet_freeze(struct virtio_device *vdev) > { > struct virtnet_info *vi = vdev->priv; > > - virtqueue_disable_cb(vi->rvq); > - virtqueue_disable_cb(vi->svq); > - if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) > - virtqueue_disable_cb(vi->cvq); > - > netif_device_detach(vi->dev); > cancel_delayed_work_sync(&vi->refill); > > -- > 1.7.9.111.gf3fb0 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 28 May 2012 15:53:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > On Wed, Apr 04, 2012 at 12:19:54PM +0300, Michael S. Tsirkin wrote: > > disable_cb is just an optimization: it > > can not guarantee that there are no callbacks. > > > > I didn't yet figure out whether a callback > > in freeze will trigger a bug, but disable_cb > > won't address it in any case. So let's remove > > the useless calls as a first step. > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > Looks like this isn't in the 3.5 pull request - > just lost in the shuffle? > disable_cb is advisory so can't be relied upon. I always (try to?) reply as I accept patches. This one did slip by, but it's harmless so no need to push AFAICT. Applied. Thanks! Rusty. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi all, On Wed, 30 May 2012 19:41:47 +0930 Rusty Russell <rusty@rustcorp.com.au> wrote: > > On Mon, 28 May 2012 15:53:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > > On Wed, Apr 04, 2012 at 12:19:54PM +0300, Michael S. Tsirkin wrote: > > > disable_cb is just an optimization: it > > > can not guarantee that there are no callbacks. > > > > > > I didn't yet figure out whether a callback > > > in freeze will trigger a bug, but disable_cb > > > won't address it in any case. So let's remove > > > the useless calls as a first step. > > > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > > > Looks like this isn't in the 3.5 pull request - > > just lost in the shuffle? > > disable_cb is advisory so can't be relied upon. > > I always (try to?) reply as I accept patches. > > This one did slip by, but it's harmless so no need to push AFAICT. > > Applied. This patch exists in two trees in linux-next already ... Davem's net tree (so presumably he will send it to Linus shortly) and Michael's vhost tree (is that tree needed any more?). Presumably it is now also in the rr tree?
On Thu, May 31, 2012 at 06:35:08PM +1000, Stephen Rothwell wrote: > Hi all, > > On Wed, 30 May 2012 19:41:47 +0930 Rusty Russell <rusty@rustcorp.com.au> wrote: > > > > On Mon, 28 May 2012 15:53:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > > > On Wed, Apr 04, 2012 at 12:19:54PM +0300, Michael S. Tsirkin wrote: > > > > disable_cb is just an optimization: it > > > > can not guarantee that there are no callbacks. > > > > > > > > I didn't yet figure out whether a callback > > > > in freeze will trigger a bug, but disable_cb > > > > won't address it in any case. So let's remove > > > > the useless calls as a first step. > > > > > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > > > > > Looks like this isn't in the 3.5 pull request - > > > just lost in the shuffle? > > > disable_cb is advisory so can't be relied upon. > > > > I always (try to?) reply as I accept patches. > > > > This one did slip by, but it's harmless so no need to push AFAICT. > > > > Applied. > > This patch exists in two trees in linux-next already ... Davem's net tree > (so presumably he will send it to Linus shortly) and Michael's vhost tree > (is that tree needed any more?). Yes and I dropped the patch from there, just did not push yet. > Presumably it is now also in the rr > tree? > > -- > Cheers, > Stephen Rothwell sfr@canb.auug.org.au -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 31, 2012 at 11:47:17AM +0300, Michael S. Tsirkin wrote: > On Thu, May 31, 2012 at 06:35:08PM +1000, Stephen Rothwell wrote: > > Hi all, > > > > On Wed, 30 May 2012 19:41:47 +0930 Rusty Russell <rusty@rustcorp.com.au> wrote: > > > > > > On Mon, 28 May 2012 15:53:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > > > > On Wed, Apr 04, 2012 at 12:19:54PM +0300, Michael S. Tsirkin wrote: > > > > > disable_cb is just an optimization: it > > > > > can not guarantee that there are no callbacks. > > > > > > > > > > I didn't yet figure out whether a callback > > > > > in freeze will trigger a bug, but disable_cb > > > > > won't address it in any case. So let's remove > > > > > the useless calls as a first step. > > > > > > > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > > > > > > > Looks like this isn't in the 3.5 pull request - > > > > just lost in the shuffle? > > > > disable_cb is advisory so can't be relied upon. > > > > > > I always (try to?) reply as I accept patches. > > > > > > This one did slip by, but it's harmless so no need to push AFAICT. > > > > > > Applied. > > > > This patch exists in two trees in linux-next already ... Davem's net tree > > (so presumably he will send it to Linus shortly) and Michael's vhost tree > > (is that tree needed any more?). > > Yes and I dropped the patch from there, just did not push yet. pushed. There's usually not too much in my tree but it helps me a lot that it's in linux-next. > > Presumably it is now also in the rr > > tree? > > > > -- > > Cheers, > > Stephen Rothwell sfr@canb.auug.org.au > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 019da01..971931e5 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1182,11 +1182,6 @@ static int virtnet_freeze(struct virtio_device *vdev) { struct virtnet_info *vi = vdev->priv; - virtqueue_disable_cb(vi->rvq); - virtqueue_disable_cb(vi->svq); - if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) - virtqueue_disable_cb(vi->cvq); - netif_device_detach(vi->dev); cancel_delayed_work_sync(&vi->refill);
disable_cb is just an optimization: it can not guarantee that there are no callbacks. I didn't yet figure out whether a callback in freeze will trigger a bug, but disable_cb won't address it in any case. So let's remove the useless calls as a first step. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- drivers/net/virtio_net.c | 5 ----- 1 files changed, 0 insertions(+), 5 deletions(-)