| Message ID | 20240426065441.120710-2-hengqi@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio_net: support getting initial value of irq coalesce | expand |
On Fri, Apr 26, 2024 at 2:54 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > From: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82 > > Based on the description provided in the above specification, we have > enabled the virtio-net driver to support acquiring some response > information from the device via the CVQ (Control Virtqueue). > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> I wonder if we need to tweak the spec as it has: """ Upon disabling and re-enabling a transmit virtqueue, the device MUST set the coalescing parameters of the virtqueue to those configured through the VIRTIO_NET_CTRL_NOTF_COAL_TX_SET command, or, if the driver did not set any TX coalescing parameters, to 0. """ So for reset, this patch tells us the device would have a non-zero default value. But spec tolds us after vq reset, it has a zero default value ... Thanks > --- > drivers/net/virtio_net.c | 24 +++++++++++++++++------- > 1 file changed, 17 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 7176b956460b..3bc9b1e621db 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi, > * supported by the hypervisor, as indicated by feature bits, should > * never fail unless improperly formatted. > */ > -static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > - struct scatterlist *out) > +static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd, > + struct scatterlist *out, > + struct scatterlist *in) > { > - struct scatterlist *sgs[4], hdr, stat; > - unsigned out_num = 0, tmp; > + struct scatterlist *sgs[5], hdr, stat; > + u32 out_num = 0, tmp, in_num = 0; > int ret; > > /* Caller should know better */ > @@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > /* Add return status. */ > sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); > - sgs[out_num] = &stat; > + sgs[out_num + in_num++] = &stat; > > - BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > - ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); > + if (in) > + sgs[out_num + in_num++] = in; > + > + BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC); > if (ret < 0) { > dev_warn(&vi->vdev->dev, > "Failed to add sgs for command vq: %d\n.", ret); > @@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > return vi->ctrl->status == VIRTIO_NET_OK; > } > > +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > + struct scatterlist *out) > +{ > + return virtnet_send_command_reply(vi, class, cmd, out, NULL); > +} > + > static int virtnet_set_mac_address(struct net_device *dev, void *p) > { > struct virtnet_info *vi = netdev_priv(dev); > -- > 2.32.0.3.g01195cf9f >
On Tue, 7 May 2024 14:24:19 +0800, Jason Wang <jasowang@redhat.com> wrote: > On Fri, Apr 26, 2024 at 2:54 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > > > From: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82 > > > > Based on the description provided in the above specification, we have > > enabled the virtio-net driver to support acquiring some response > > information from the device via the CVQ (Control Virtqueue). > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > I wonder if we need to tweak the spec as it has: > > """ > Upon disabling and re-enabling a transmit virtqueue, the device MUST > set the coalescing parameters of the virtqueue > to those configured through the VIRTIO_NET_CTRL_NOTF_COAL_TX_SET > command, or, if the driver did not set any TX coalescing parameters, > to 0. > """ > > So for reset, this patch tells us the device would have a non-zero > default value. > > But spec tolds us after vq reset, it has a zero default value ... Maybe we add a bool or flag for driver to mark whether the user has actively configured interrupt coalescing parameters. Then we can take actions when vq reset occurs? Thanks. > > Thanks > > > > --- > > drivers/net/virtio_net.c | 24 +++++++++++++++++------- > > 1 file changed, 17 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index 7176b956460b..3bc9b1e621db 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi, > > * supported by the hypervisor, as indicated by feature bits, should > > * never fail unless improperly formatted. > > */ > > -static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > - struct scatterlist *out) > > +static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd, > > + struct scatterlist *out, > > + struct scatterlist *in) > > { > > - struct scatterlist *sgs[4], hdr, stat; > > - unsigned out_num = 0, tmp; > > + struct scatterlist *sgs[5], hdr, stat; > > + u32 out_num = 0, tmp, in_num = 0; > > int ret; > > > > /* Caller should know better */ > > @@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > /* Add return status. */ > > sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); > > - sgs[out_num] = &stat; > > + sgs[out_num + in_num++] = &stat; > > > > - BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > > - ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); > > + if (in) > > + sgs[out_num + in_num++] = in; > > + > > + BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); > > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC); > > if (ret < 0) { > > dev_warn(&vi->vdev->dev, > > "Failed to add sgs for command vq: %d\n.", ret); > > @@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > return vi->ctrl->status == VIRTIO_NET_OK; > > } > > > > +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > + struct scatterlist *out) > > +{ > > + return virtnet_send_command_reply(vi, class, cmd, out, NULL); > > +} > > + > > static int virtnet_set_mac_address(struct net_device *dev, void *p) > > { > > struct virtnet_info *vi = netdev_priv(dev); > > -- > > 2.32.0.3.g01195cf9f > > >
On Tue, May 7, 2024 at 2:56 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > On Tue, 7 May 2024 14:24:19 +0800, Jason Wang <jasowang@redhat.com> wrote: > > On Fri, Apr 26, 2024 at 2:54 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > > > > > From: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > > > As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82 > > > > > > Based on the description provided in the above specification, we have > > > enabled the virtio-net driver to support acquiring some response > > > information from the device via the CVQ (Control Virtqueue). > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > I wonder if we need to tweak the spec as it has: > > > > """ > > Upon disabling and re-enabling a transmit virtqueue, the device MUST > > set the coalescing parameters of the virtqueue > > to those configured through the VIRTIO_NET_CTRL_NOTF_COAL_TX_SET > > command, or, if the driver did not set any TX coalescing parameters, > > to 0. > > """ > > > > So for reset, this patch tells us the device would have a non-zero > > default value. > > > > But spec tolds us after vq reset, it has a zero default value ... > > Maybe we add a bool or flag for driver to mark whether the user has actively > configured interrupt coalescing parameters. Then we can take actions when > vq reset occurs? I basically mean we probably need to tweak the spec. For example say the device may have a default value for coalescing so driver need to read them. Thanks > > Thanks. > > > > > Thanks > > > > > > > --- > > > drivers/net/virtio_net.c | 24 +++++++++++++++++------- > > > 1 file changed, 17 insertions(+), 7 deletions(-) > > > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > > index 7176b956460b..3bc9b1e621db 100644 > > > --- a/drivers/net/virtio_net.c > > > +++ b/drivers/net/virtio_net.c > > > @@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi, > > > * supported by the hypervisor, as indicated by feature bits, should > > > * never fail unless improperly formatted. > > > */ > > > -static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > - struct scatterlist *out) > > > +static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd, > > > + struct scatterlist *out, > > > + struct scatterlist *in) > > > { > > > - struct scatterlist *sgs[4], hdr, stat; > > > - unsigned out_num = 0, tmp; > > > + struct scatterlist *sgs[5], hdr, stat; > > > + u32 out_num = 0, tmp, in_num = 0; > > > int ret; > > > > > > /* Caller should know better */ > > > @@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > > > /* Add return status. */ > > > sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); > > > - sgs[out_num] = &stat; > > > + sgs[out_num + in_num++] = &stat; > > > > > > - BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > > > - ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); > > > + if (in) > > > + sgs[out_num + in_num++] = in; > > > + > > > + BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); > > > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC); > > > if (ret < 0) { > > > dev_warn(&vi->vdev->dev, > > > "Failed to add sgs for command vq: %d\n.", ret); > > > @@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > return vi->ctrl->status == VIRTIO_NET_OK; > > > } > > > > > > +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > + struct scatterlist *out) > > > +{ > > > + return virtnet_send_command_reply(vi, class, cmd, out, NULL); > > > +} > > > + > > > static int virtnet_set_mac_address(struct net_device *dev, void *p) > > > { > > > struct virtnet_info *vi = netdev_priv(dev); > > > -- > > > 2.32.0.3.g01195cf9f > > > > > >
On Wed, 8 May 2024 10:20:05 +0800, Jason Wang <jasowang@redhat.com> wrote: > On Tue, May 7, 2024 at 2:56 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > > > On Tue, 7 May 2024 14:24:19 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > On Fri, Apr 26, 2024 at 2:54 PM Heng Qi <hengqi@linux.alibaba.com> wrote: > > > > > > > > From: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > > > > > As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82 > > > > > > > > Based on the description provided in the above specification, we have > > > > enabled the virtio-net driver to support acquiring some response > > > > information from the device via the CVQ (Control Virtqueue). > > > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > > > I wonder if we need to tweak the spec as it has: > > > > > > """ > > > Upon disabling and re-enabling a transmit virtqueue, the device MUST > > > set the coalescing parameters of the virtqueue > > > to those configured through the VIRTIO_NET_CTRL_NOTF_COAL_TX_SET > > > command, or, if the driver did not set any TX coalescing parameters, > > > to 0. > > > """ > > > > > > So for reset, this patch tells us the device would have a non-zero > > > default value. > > > > > > But spec tolds us after vq reset, it has a zero default value ... > > > > Maybe we add a bool or flag for driver to mark whether the user has actively > > configured interrupt coalescing parameters. Then we can take actions when > > vq reset occurs? > > I basically mean we probably need to tweak the spec. For example say > the device may have a default value for coalescing so driver need to > read them. Well, I'll post a tweak patch, and since the current virtio spec mailing list is still not ready, I'll Cc people who were previously involved in the discussion. Thanks. > > Thanks > > > > > Thanks. > > > > > > > > Thanks > > > > > > > > > > --- > > > > drivers/net/virtio_net.c | 24 +++++++++++++++++------- > > > > 1 file changed, 17 insertions(+), 7 deletions(-) > > > > > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > > > index 7176b956460b..3bc9b1e621db 100644 > > > > --- a/drivers/net/virtio_net.c > > > > +++ b/drivers/net/virtio_net.c > > > > @@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi, > > > > * supported by the hypervisor, as indicated by feature bits, should > > > > * never fail unless improperly formatted. > > > > */ > > > > -static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > - struct scatterlist *out) > > > > +static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd, > > > > + struct scatterlist *out, > > > > + struct scatterlist *in) > > > > { > > > > - struct scatterlist *sgs[4], hdr, stat; > > > > - unsigned out_num = 0, tmp; > > > > + struct scatterlist *sgs[5], hdr, stat; > > > > + u32 out_num = 0, tmp, in_num = 0; > > > > int ret; > > > > > > > > /* Caller should know better */ > > > > @@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > > > > > /* Add return status. */ > > > > sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); > > > > - sgs[out_num] = &stat; > > > > + sgs[out_num + in_num++] = &stat; > > > > > > > > - BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); > > > > - ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); > > > > + if (in) > > > > + sgs[out_num + in_num++] = in; > > > > + > > > > + BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); > > > > + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC); > > > > if (ret < 0) { > > > > dev_warn(&vi->vdev->dev, > > > > "Failed to add sgs for command vq: %d\n.", ret); > > > > @@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > return vi->ctrl->status == VIRTIO_NET_OK; > > > > } > > > > > > > > +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > > > > + struct scatterlist *out) > > > > +{ > > > > + return virtnet_send_command_reply(vi, class, cmd, out, NULL); > > > > +} > > > > + > > > > static int virtnet_set_mac_address(struct net_device *dev, void *p) > > > > { > > > > struct virtnet_info *vi = netdev_priv(dev); > > > > -- > > > > 2.32.0.3.g01195cf9f > > > > > > > > > >
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 7176b956460b..3bc9b1e621db 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi, * supported by the hypervisor, as indicated by feature bits, should * never fail unless improperly formatted. */ -static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, - struct scatterlist *out) +static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd, + struct scatterlist *out, + struct scatterlist *in) { - struct scatterlist *sgs[4], hdr, stat; - unsigned out_num = 0, tmp; + struct scatterlist *sgs[5], hdr, stat; + u32 out_num = 0, tmp, in_num = 0; int ret; /* Caller should know better */ @@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, /* Add return status. */ sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); - sgs[out_num] = &stat; + sgs[out_num + in_num++] = &stat; - BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); - ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); + if (in) + sgs[out_num + in_num++] = in; + + BUG_ON(out_num + in_num > ARRAY_SIZE(sgs)); + ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC); if (ret < 0) { dev_warn(&vi->vdev->dev, "Failed to add sgs for command vq: %d\n.", ret); @@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, return vi->ctrl->status == VIRTIO_NET_OK; } +static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, + struct scatterlist *out) +{ + return virtnet_send_command_reply(vi, class, cmd, out, NULL); +} + static int virtnet_set_mac_address(struct net_device *dev, void *p) { struct virtnet_info *vi = netdev_priv(dev);