[PATCH net-next 0/2] virtio_net: support getting initial value of irq coalesce

[PATCH net-next 0/2] virtio_net: support getting initial value of irq coalesce

[Heng Qi]

Patch 1 from Xuan: the virtnet cvq supports to get
result from the device.

Patch 2 reuses the VIRTIO_NET_CTRL_NOTF_COAL_VQ_GET cmd to
get init coalesce value.

Heng Qi (1):
  virtio_net: get init coalesce value when probe

Xuan Zhuo (1):
  virtio_net: virtnet_send_command supports command-specific-result

 drivers/net/virtio_net.c | 92 ++++++++++++++++++++++++++++++++++------
 1 file changed, 78 insertions(+), 14 deletions(-)

-- 
2.32.0.3.g01195cf9f

[PATCH net-next 1/2] virtio_net: virtnet_send_command supports command-specific-result

[Heng Qi]

From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82

The virtnet cvq supports to get result from the device.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
 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

[PATCH net-next 2/2] virtio_net: get init coalesce value when probe

[Heng Qi]

Currently, virtio-net lacks a way to obtain the default coalesce
values of the device during the probe phase. That is, the device
may have default experience values, but the user uses "ethtool -c"
to query that the values are still 0.

Therefore, we reuse VIRTIO_NET_CTRL_NOTF_COAL_VQ_GET to complete the goal.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
---
 drivers/net/virtio_net.c | 68 +++++++++++++++++++++++++++++++++++-----
 1 file changed, 61 insertions(+), 7 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 3bc9b1e621db..fe0c15819dd3 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -4623,6 +4623,46 @@ static int virtnet_validate(struct virtio_device *vdev)
 	return 0;
 }
 
+static int virtnet_get_coal_init_value(struct virtnet_info *vi,
+				       u16 _vqn, bool is_tx)
+{
+	struct virtio_net_ctrl_coal *coal = &vi->ctrl->coal_vq.coal;
+	__le16 *vqn = &vi->ctrl->coal_vq.vqn;
+	struct scatterlist sgs_in, sgs_out;
+	u32 usecs, pkts, i;
+	bool ret;
+
+	*vqn = cpu_to_le16(_vqn);
+
+	sg_init_one(&sgs_out, vqn, sizeof(*vqn));
+	sg_init_one(&sgs_in, coal, sizeof(*coal));
+	ret = virtnet_send_command_reply(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+					 VIRTIO_NET_CTRL_NOTF_COAL_VQ_GET,
+					 &sgs_out, &sgs_in);
+	if (!ret)
+		return ret;
+
+	usecs = le32_to_cpu(coal->max_usecs);
+	pkts = le32_to_cpu(coal->max_packets);
+	if (is_tx) {
+		vi->intr_coal_tx.max_usecs = usecs;
+		vi->intr_coal_tx.max_packets = pkts;
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			vi->sq[i].intr_coal.max_usecs = usecs;
+			vi->sq[i].intr_coal.max_packets = pkts;
+		}
+	} else {
+		vi->intr_coal_rx.max_usecs = usecs;
+		vi->intr_coal_rx.max_packets = pkts;
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			vi->rq[i].intr_coal.max_usecs = usecs;
+			vi->rq[i].intr_coal.max_packets = pkts;
+		}
+	}
+
+	return 0;
+}
+
 static bool virtnet_check_guest_gso(const struct virtnet_info *vi)
 {
 	return virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
@@ -4885,13 +4925,6 @@ static int virtnet_probe(struct virtio_device *vdev)
 			vi->intr_coal_tx.max_packets = 0;
 	}
 
-	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) {
-		/* The reason is the same as VIRTIO_NET_F_NOTF_COAL. */
-		for (i = 0; i < vi->max_queue_pairs; i++)
-			if (vi->sq[i].napi.weight)
-				vi->sq[i].intr_coal.max_packets = 1;
-	}
-
 #ifdef CONFIG_SYSFS
 	if (vi->mergeable_rx_bufs)
 		dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
@@ -4926,6 +4959,27 @@ static int virtnet_probe(struct virtio_device *vdev)
 
 	virtio_device_ready(vdev);
 
+	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) {
+		/* The reason is the same as VIRTIO_NET_F_NOTF_COAL. */
+		for (i = 0; i < vi->max_queue_pairs; i++)
+			if (vi->sq[i].napi.weight)
+				vi->sq[i].intr_coal.max_packets = 1;
+
+		/* The loop exits if the default value from any
+		 * queue is successfully read.
+		 */
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			err = virtnet_get_coal_init_value(vi, rxq2vq(i), false);
+			if (!err)
+				break;
+		}
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			err = virtnet_get_coal_init_value(vi, txq2vq(i), true);
+			if (!err)
+				break;
+		}
+	}
+
 	_virtnet_set_queues(vi, vi->curr_queue_pairs);
 
 	/* a random MAC address has been assigned, notify the device.
-- 
2.32.0.3.g01195cf9f

Re: [PATCH net-next 1/2] virtio_net: virtnet_send_command supports command-specific-result

[Jiri Pirko]

Tue, Apr 23, 2024 at 10:42:25AM CEST, hengqi@linux.alibaba.com wrote:
>From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
>
>As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82
>
>The virtnet cvq supports to get result from the device.

Is this a statement about current status, cause it sounds so. Could you
make it clear by changing the patch subject and description to use
imperative mood please. Command the codebase what to do.

Thanks!

>
>Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
>---
> 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
>
>

Re: [PATCH net-next 1/2] virtio_net: virtnet_send_command supports command-specific-result

[Heng Qi]

在 2024/4/23 下午6:17, Jiri Pirko 写道:
> Tue, Apr 23, 2024 at 10:42:25AM CEST, hengqi@linux.alibaba.com wrote:
>> From: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
>>
>> As the spec https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82
>>
>> The virtnet cvq supports to get result from the device.
> Is this a statement about current status, cause it sounds so. Could you
> make it clear by changing the patch subject and description to use
> imperative mood please. Command the codebase what to do.

Sure. Will add more text in v2.

>
> Thanks!
>
>> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
>> ---
>> 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
>>
>>