diff mbox series

[net-next,5/5] virtio-net: support tx netdim

Message ID ef5d159875745040e406473bd5c03e9875742ff5.1697093455.git.hengqi@linux.alibaba.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series virtio-net: support dynamic coalescing moderation | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1361 this patch: 1361
netdev/cc_maintainers success CCed 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 1386 this patch: 1386
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1388 this patch: 1388
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 84 exceeds 80 columns WARNING: line length of 85 exceeds 80 columns WARNING: line length of 86 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Heng Qi Oct. 12, 2023, 7:44 a.m. UTC
Similar to rx netdim, this patch supports adaptive tx
coalescing moderation for the virtio-net.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
---
 drivers/net/virtio_net.c | 143 ++++++++++++++++++++++++++++++++-------
 1 file changed, 119 insertions(+), 24 deletions(-)

Comments

Jason Wang Oct. 25, 2023, 3:35 a.m. UTC | #1
On Thu, Oct 12, 2023 at 3:44 PM Heng Qi <hengqi@linux.alibaba.com> wrote:
>
> Similar to rx netdim, this patch supports adaptive tx
> coalescing moderation for the virtio-net.
>
> Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
> ---
>  drivers/net/virtio_net.c | 143 ++++++++++++++++++++++++++++++++-------
>  1 file changed, 119 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 6ad2890a7909..1c680cb09d48 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -154,6 +154,15 @@ struct send_queue {
>
>         struct virtnet_sq_stats stats;
>
> +       /* The number of tx notifications */
> +       u16 calls;
> +
> +       /* Is dynamic interrupt moderation enabled? */
> +       bool dim_enabled;
> +
> +       /* Dynamic Interrupt Moderation */
> +       struct dim dim;
> +
>         struct virtnet_interrupt_coalesce intr_coal;
>
>         struct napi_struct napi;
> @@ -317,8 +326,9 @@ struct virtnet_info {
>         u8 duplex;
>         u32 speed;
>
> -       /* Is rx dynamic interrupt moderation enabled? */
> +       /* Is dynamic interrupt moderation enabled? */
>         bool rx_dim_enabled;
> +       bool tx_dim_enabled;
>
>         /* Interrupt coalescing settings */
>         struct virtnet_interrupt_coalesce intr_coal_tx;
> @@ -464,19 +474,40 @@ static bool virtqueue_napi_complete(struct napi_struct *napi,
>         return false;
>  }
>
> +static void virtnet_tx_dim_work(struct work_struct *work);
> +
> +static void virtnet_tx_dim_update(struct virtnet_info *vi, struct send_queue *sq)
> +{
> +       struct virtnet_sq_stats *stats = &sq->stats;
> +       struct dim_sample cur_sample = {};
> +
> +       u64_stats_update_begin(&sq->stats.syncp);
> +       dim_update_sample(sq->calls, stats->packets,
> +                         stats->bytes, &cur_sample);
> +       u64_stats_update_end(&sq->stats.syncp);
> +
> +       net_dim(&sq->dim, cur_sample);
> +}
> +
>  static void skb_xmit_done(struct virtqueue *vq)
>  {
>         struct virtnet_info *vi = vq->vdev->priv;
> -       struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
> +       struct send_queue *sq = &vi->sq[vq2txq(vq)];
> +       struct napi_struct *napi = &sq->napi;
> +
> +       sq->calls++;

I wonder what's the impact of this counters for netdim. As we have a
mode of orphan skb in xmit.

We need to test to see.

Thanks
Michael S. Tsirkin Oct. 25, 2023, 5:50 a.m. UTC | #2
On Wed, Oct 25, 2023 at 11:35:43AM +0800, Jason Wang wrote:
> On Thu, Oct 12, 2023 at 3:44 PM Heng Qi <hengqi@linux.alibaba.com> wrote:
> >
> > Similar to rx netdim, this patch supports adaptive tx
> > coalescing moderation for the virtio-net.
> >
> > Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
> > ---
> >  drivers/net/virtio_net.c | 143 ++++++++++++++++++++++++++++++++-------
> >  1 file changed, 119 insertions(+), 24 deletions(-)
> >
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index 6ad2890a7909..1c680cb09d48 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -154,6 +154,15 @@ struct send_queue {
> >
> >         struct virtnet_sq_stats stats;
> >
> > +       /* The number of tx notifications */
> > +       u16 calls;
> > +
> > +       /* Is dynamic interrupt moderation enabled? */
> > +       bool dim_enabled;
> > +
> > +       /* Dynamic Interrupt Moderation */
> > +       struct dim dim;
> > +
> >         struct virtnet_interrupt_coalesce intr_coal;
> >
> >         struct napi_struct napi;
> > @@ -317,8 +326,9 @@ struct virtnet_info {
> >         u8 duplex;
> >         u32 speed;
> >
> > -       /* Is rx dynamic interrupt moderation enabled? */
> > +       /* Is dynamic interrupt moderation enabled? */
> >         bool rx_dim_enabled;
> > +       bool tx_dim_enabled;
> >
> >         /* Interrupt coalescing settings */
> >         struct virtnet_interrupt_coalesce intr_coal_tx;
> > @@ -464,19 +474,40 @@ static bool virtqueue_napi_complete(struct napi_struct *napi,
> >         return false;
> >  }
> >
> > +static void virtnet_tx_dim_work(struct work_struct *work);
> > +
> > +static void virtnet_tx_dim_update(struct virtnet_info *vi, struct send_queue *sq)
> > +{
> > +       struct virtnet_sq_stats *stats = &sq->stats;
> > +       struct dim_sample cur_sample = {};
> > +
> > +       u64_stats_update_begin(&sq->stats.syncp);
> > +       dim_update_sample(sq->calls, stats->packets,
> > +                         stats->bytes, &cur_sample);
> > +       u64_stats_update_end(&sq->stats.syncp);
> > +
> > +       net_dim(&sq->dim, cur_sample);
> > +}
> > +
> >  static void skb_xmit_done(struct virtqueue *vq)
> >  {
> >         struct virtnet_info *vi = vq->vdev->priv;
> > -       struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
> > +       struct send_queue *sq = &vi->sq[vq2txq(vq)];
> > +       struct napi_struct *napi = &sq->napi;
> > +
> > +       sq->calls++;
> 
> I wonder what's the impact of this counters for netdim. As we have a
> mode of orphan skb in xmit.
> 
> We need to test to see.
> 
> Thanks

Agreed, performance patches should come with performance results.
diff mbox series

Patch

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 6ad2890a7909..1c680cb09d48 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -154,6 +154,15 @@  struct send_queue {
 
 	struct virtnet_sq_stats stats;
 
+	/* The number of tx notifications */
+	u16 calls;
+
+	/* Is dynamic interrupt moderation enabled? */
+	bool dim_enabled;
+
+	/* Dynamic Interrupt Moderation */
+	struct dim dim;
+
 	struct virtnet_interrupt_coalesce intr_coal;
 
 	struct napi_struct napi;
@@ -317,8 +326,9 @@  struct virtnet_info {
 	u8 duplex;
 	u32 speed;
 
-	/* Is rx dynamic interrupt moderation enabled? */
+	/* Is dynamic interrupt moderation enabled? */
 	bool rx_dim_enabled;
+	bool tx_dim_enabled;
 
 	/* Interrupt coalescing settings */
 	struct virtnet_interrupt_coalesce intr_coal_tx;
@@ -464,19 +474,40 @@  static bool virtqueue_napi_complete(struct napi_struct *napi,
 	return false;
 }
 
+static void virtnet_tx_dim_work(struct work_struct *work);
+
+static void virtnet_tx_dim_update(struct virtnet_info *vi, struct send_queue *sq)
+{
+	struct virtnet_sq_stats *stats = &sq->stats;
+	struct dim_sample cur_sample = {};
+
+	u64_stats_update_begin(&sq->stats.syncp);
+	dim_update_sample(sq->calls, stats->packets,
+			  stats->bytes, &cur_sample);
+	u64_stats_update_end(&sq->stats.syncp);
+
+	net_dim(&sq->dim, cur_sample);
+}
+
 static void skb_xmit_done(struct virtqueue *vq)
 {
 	struct virtnet_info *vi = vq->vdev->priv;
-	struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi;
+	struct send_queue *sq = &vi->sq[vq2txq(vq)];
+	struct napi_struct *napi = &sq->napi;
+
+	sq->calls++;
 
 	/* Suppress further interrupts. */
 	virtqueue_disable_cb(vq);
 
-	if (napi->weight)
+	if (napi->weight) {
 		virtqueue_napi_schedule(napi, vq);
-	else
+	} else {
+		if (sq->dim_enabled)
+			virtnet_tx_dim_update(vi, sq);
 		/* We were probably waiting for more output buffers. */
 		netif_wake_subqueue(vi->dev, vq2txq(vq));
+	}
 }
 
 #define MRG_CTX_HEADER_SHIFT 22
@@ -2217,6 +2248,7 @@  static void virtnet_disable_queue_pair(struct virtnet_info *vi, int qp_index)
 	napi_disable(&vi->rq[qp_index].napi);
 	xdp_rxq_info_unreg(&vi->rq[qp_index].xdp_rxq);
 	cancel_work_sync(&vi->rq[qp_index].dim.work);
+	cancel_work_sync(&vi->sq[qp_index].dim.work);
 }
 
 static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index)
@@ -2236,6 +2268,8 @@  static int virtnet_enable_queue_pair(struct virtnet_info *vi, int qp_index)
 
 	INIT_WORK(&vi->rq[qp_index].dim.work, virtnet_rx_dim_work);
 	vi->rq[qp_index].dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
+	INIT_WORK(&vi->sq[qp_index].dim.work, virtnet_tx_dim_work);
+	vi->sq[qp_index].dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 
 	virtnet_napi_enable(vi->rq[qp_index].vq, &vi->rq[qp_index].napi);
 	virtnet_napi_tx_enable(vi, vi->sq[qp_index].vq, &vi->sq[qp_index].napi);
@@ -2316,6 +2350,9 @@  static int virtnet_poll_tx(struct napi_struct *napi, int budget)
 				__netif_tx_unlock(txq);
 				__napi_schedule(napi);
 			}
+		} else {
+			if (sq->dim_enabled)
+				virtnet_tx_dim_update(vi, sq);
 		}
 	}
 
@@ -3353,24 +3390,42 @@  static int virtnet_get_link_ksettings(struct net_device *dev,
 static int virtnet_send_tx_notf_coal_cmds(struct virtnet_info *vi,
 					  struct ethtool_coalesce *ec)
 {
+	bool tx_ctrl_dim_on = !!ec->use_adaptive_tx_coalesce;
 	struct scatterlist sgs_tx;
 	int i;
 
-	vi->ctrl->coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
-	vi->ctrl->coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
-	sg_init_one(&sgs_tx, &vi->ctrl->coal_tx, sizeof(vi->ctrl->coal_tx));
-
-	if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
-				  VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
-				  &sgs_tx))
+	if (tx_ctrl_dim_on && (ec->tx_coalesce_usecs != vi->intr_coal_tx.max_usecs ||
+			       ec->tx_max_coalesced_frames != vi->intr_coal_tx.max_packets))
 		return -EINVAL;
 
-	/* Save parameters */
-	vi->intr_coal_tx.max_usecs = ec->tx_coalesce_usecs;
-	vi->intr_coal_tx.max_packets = ec->tx_max_coalesced_frames;
-	for (i = 0; i < vi->max_queue_pairs; i++) {
-		vi->sq[i].intr_coal.max_usecs = ec->tx_coalesce_usecs;
-		vi->sq[i].intr_coal.max_packets = ec->tx_max_coalesced_frames;
+	if (tx_ctrl_dim_on) {
+		if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_VQ_NOTF_COAL)) {
+			vi->tx_dim_enabled = true;
+			for (i = 0; i < vi->max_queue_pairs; i++)
+				vi->sq[i].dim_enabled = true;
+		} else {
+			return -EOPNOTSUPP;
+		}
+	} else {
+		vi->tx_dim_enabled = false;
+		for (i = 0; i < vi->max_queue_pairs; i++)
+			vi->sq[i].dim_enabled = false;
+
+		vi->ctrl->coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs);
+		vi->ctrl->coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames);
+		sg_init_one(&sgs_tx, &vi->ctrl->coal_tx, sizeof(vi->ctrl->coal_tx));
+
+		if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL,
+					  VIRTIO_NET_CTRL_NOTF_COAL_TX_SET,
+					  &sgs_tx))
+			return -EINVAL;
+
+		vi->intr_coal_tx.max_usecs = ec->tx_coalesce_usecs;
+		vi->intr_coal_tx.max_packets = ec->tx_max_coalesced_frames;
+		for (i = 0; i < vi->max_queue_pairs; i++) {
+			vi->sq[i].intr_coal.max_usecs = ec->tx_coalesce_usecs;
+			vi->sq[i].intr_coal.max_packets = ec->tx_max_coalesced_frames;
+		}
 	}
 
 	return 0;
@@ -3436,11 +3491,37 @@  static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi,
 	return 0;
 }
 
+static void virtnet_tx_dim_work(struct work_struct *work)
+{
+	struct dim *dim = container_of(work, struct dim, work);
+	struct send_queue *sq = container_of(dim,
+					     struct send_queue, dim);
+	struct virtnet_info *vi = sq->vq->vdev->priv;
+	struct net_device *dev = vi->dev;
+	struct dim_cq_moder update_moder;
+	int qnum = sq - vi->sq, err;
+
+	update_moder = net_dim_get_tx_moderation(dim->mode, dim->profile_ix);
+	if (update_moder.usec != vi->sq[qnum].intr_coal.max_usecs ||
+	    update_moder.pkts != vi->sq[qnum].intr_coal.max_packets) {
+		rtnl_lock();
+		err = virtnet_send_tx_ctrl_coal_vq_cmd(vi, qnum,
+						       update_moder.usec,
+						       update_moder.pkts);
+		if (err)
+			pr_debug("%s: Failed to send dim parameters on txq%d\n",
+				 dev->name, (int)(sq - vi->sq));
+		rtnl_unlock();
+	}
+
+	dim->state = DIM_START_MEASURE;
+}
+
 static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi,
 					  struct ethtool_coalesce *ec,
 					  u16 queue)
 {
-	bool rx_ctrl_dim_on;
+	bool rx_ctrl_dim_on, tx_ctrl_dim_on;
 	u32 max_usecs, max_packets;
 	int err;
 
@@ -3462,11 +3543,23 @@  static int virtnet_send_notf_coal_vq_cmds(struct virtnet_info *vi,
 			return err;
 	}
 
-	err = virtnet_send_tx_ctrl_coal_vq_cmd(vi, queue,
-					       ec->tx_coalesce_usecs,
-					       ec->tx_max_coalesced_frames);
-	if (err)
-		return err;
+	tx_ctrl_dim_on = !!ec->use_adaptive_tx_coalesce;
+	max_usecs = vi->sq[queue].intr_coal.max_usecs;
+	max_packets = vi->sq[queue].intr_coal.max_packets;
+	if (tx_ctrl_dim_on && (ec->tx_coalesce_usecs != max_usecs ||
+			       ec->tx_max_coalesced_frames != max_packets))
+		return -EINVAL;
+
+	if (tx_ctrl_dim_on) {
+		vi->sq[queue].dim_enabled = true;
+	} else {
+		vi->sq[queue].dim_enabled = false;
+		err = virtnet_send_tx_ctrl_coal_vq_cmd(vi, queue,
+						       ec->tx_coalesce_usecs,
+						       ec->tx_max_coalesced_frames);
+		if (err)
+			return err;
+	}
 
 	return 0;
 }
@@ -3579,6 +3672,7 @@  static int virtnet_get_coalesce(struct net_device *dev,
 		ec->tx_max_coalesced_frames = vi->intr_coal_tx.max_packets;
 		ec->rx_max_coalesced_frames = vi->intr_coal_rx.max_packets;
 		ec->use_adaptive_rx_coalesce = vi->rx_dim_enabled;
+		ec->use_adaptive_tx_coalesce = vi->tx_dim_enabled;
 	} else {
 		ec->rx_max_coalesced_frames = 1;
 
@@ -3637,6 +3731,7 @@  static int virtnet_get_per_queue_coalesce(struct net_device *dev,
 		ec->tx_max_coalesced_frames = vi->sq[queue].intr_coal.max_packets;
 		ec->rx_max_coalesced_frames = vi->rq[queue].intr_coal.max_packets;
 		ec->use_adaptive_rx_coalesce = vi->rq[queue].dim_enabled;
+		ec->use_adaptive_tx_coalesce = vi->sq[queue].dim_enabled;
 	} else {
 		ec->rx_max_coalesced_frames = 1;
 
@@ -3762,7 +3857,7 @@  static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info)
 
 static const struct ethtool_ops virtnet_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES |
-		ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_USE_ADAPTIVE_RX,
+		ETHTOOL_COALESCE_USECS | ETHTOOL_COALESCE_USE_ADAPTIVE,
 	.get_drvinfo = virtnet_get_drvinfo,
 	.get_link = ethtool_op_get_link,
 	.get_ringparam = virtnet_get_ringparam,