thr3ads.net - Linux Ethernet Bridging - [Bridge] [RFC net-next 6/9] net: dsa: Forward offloading [May 2021]

If this information is useful, please help other people find it:
Share via:

Tobias Waldekranz

2021-Apr-26 17:04 UTC

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

Allow DSA drivers to support forward offloading from a bridge by:

- Passing calls to .ndo_dfwd_{add,del}_station to the drivers.

- Recording the subordinate device of offloaded skbs in the control
  buffer so that the tagger can take the appropriate action.

Signed-off-by: Tobias Waldekranz <tobias at waldekranz.com>
---
 include/net/dsa.h |  7 +++++++
 net/dsa/slave.c   | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index 1f9ba9889034..77d4df819299 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -119,6 +119,7 @@ struct dsa_netdevice_ops {
 
 struct dsa_skb_cb {
 	struct sk_buff *clone;
+	struct net_device *sb_dev;
 };
 
 struct __dsa_skb_cb {
@@ -828,6 +829,12 @@ struct dsa_switch_ops {
 					  const struct switchdev_obj_ring_role_mrp *mrp);
 	int	(*port_mrp_del_ring_role)(struct dsa_switch *ds, int port,
 					  const struct switchdev_obj_ring_role_mrp *mrp);
+
+	/* L2 forward offloading */
+	void *	(*dfwd_add_station)(struct dsa_switch *ds, int port,
+				    struct net_device *sb_dev);
+	void	(*dfwd_del_station)(struct dsa_switch *ds, int port,
+				    struct net_device *sb_dev);
 };
 
 #define DSA_DEVLINK_PARAM_DRIVER(_id, _name, _type, _cmodes)		\
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 77b33bd161b8..3689ffa2dbb8 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -657,6 +657,13 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb,
struct net_device *dev)
 	return dsa_enqueue_skb(nskb, dev);
 }
 
+static u16 dsa_slave_select_queue(struct net_device *dev, struct sk_buff *skb,
+				  struct net_device *sb_dev)
+{
+	DSA_SKB_CB(skb)->sb_dev = sb_dev;
+	return netdev_pick_tx(dev, skb, sb_dev);
+}
+
 /* ethtool operations *******************************************************/
 
 static void dsa_slave_get_drvinfo(struct net_device *dev,
@@ -1708,10 +1715,33 @@ static int dsa_slave_fill_forward_path(struct
net_device_path_ctx *ctx,
 	return 0;
 }
 
+static void *dsa_slave_dfwd_add_station(struct net_device *dev,
+					struct net_device *sb_dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->dfwd_add_station)
+		return ds->ops->dfwd_add_station(ds, dp->index, sb_dev);
+
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
+static void dsa_slave_dfwd_del_station(struct net_device *dev,
+				       void *sb_dev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct dsa_switch *ds = dp->ds;
+
+	if (ds->ops->dfwd_del_station)
+		ds->ops->dfwd_del_station(ds, dp->index, sb_dev);
+}
+
 static const struct net_device_ops dsa_slave_netdev_ops = {
 	.ndo_open	 	= dsa_slave_open,
 	.ndo_stop		= dsa_slave_close,
 	.ndo_start_xmit		= dsa_slave_xmit,
+	.ndo_select_queue	= dsa_slave_select_queue,
 	.ndo_change_rx_flags	= dsa_slave_change_rx_flags,
 	.ndo_set_rx_mode	= dsa_slave_set_rx_mode,
 	.ndo_set_mac_address	= dsa_slave_set_mac_address,
@@ -1734,6 +1764,8 @@ static const struct net_device_ops dsa_slave_netdev_ops =
{
 	.ndo_get_devlink_port	= dsa_slave_get_devlink_port,
 	.ndo_change_mtu		= dsa_slave_change_mtu,
 	.ndo_fill_forward_path	= dsa_slave_fill_forward_path,
+	.ndo_dfwd_add_station	= dsa_slave_dfwd_add_station,
+	.ndo_dfwd_del_station	= dsa_slave_dfwd_del_station,
 };
 
 static struct device_type dsa_type = {
@@ -1914,8 +1946,8 @@ int dsa_slave_create(struct dsa_port *port)
 	slave_dev->features = master->vlan_features | NETIF_F_HW_TC;
 	if (ds->ops->port_vlan_add && ds->ops->port_vlan_del)
 		slave_dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
-	slave_dev->hw_features |= NETIF_F_HW_TC;
-	slave_dev->features |= NETIF_F_LLTX;
+	slave_dev->hw_features |= NETIF_F_HW_TC | NETIF_F_HW_L2FW_DOFFLOAD;
+	slave_dev->features |= NETIF_F_LLTX | NETIF_F_HW_L2FW_DOFFLOAD;
 	slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
 	if (!is_zero_ether_addr(port->mac))
 		ether_addr_copy(slave_dev->dev_addr, port->mac);
-- 
2.25.1

Vladimir Oltean

2021-Apr-27 10:17 UTC

head link

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

On Mon, Apr 26, 2021 at 07:04:08PM +0200, Tobias Waldekranz
wrote:> Allow DSA drivers to support forward offloading from a bridge by:
> 
> - Passing calls to .ndo_dfwd_{add,del}_station to the drivers.
> 
> - Recording the subordinate device of offloaded skbs in the control
>   buffer so that the tagger can take the appropriate action.
> 
> Signed-off-by: Tobias Waldekranz <tobias at waldekranz.com>
> ---
>  include/net/dsa.h |  7 +++++++
>  net/dsa/slave.c   | 36 ++++++++++++++++++++++++++++++++++--
>  2 files changed, 41 insertions(+), 2 deletions(-)
> 
> diff --git a/include/net/dsa.h b/include/net/dsa.h
> index 1f9ba9889034..77d4df819299 100644
> --- a/include/net/dsa.h
> +++ b/include/net/dsa.h
> @@ -119,6 +119,7 @@ struct dsa_netdevice_ops {
>  
>  struct dsa_skb_cb {
>  	struct sk_buff *clone;
> +	struct net_device *sb_dev;
>  };
>  
>  struct __dsa_skb_cb {
> @@ -828,6 +829,12 @@ struct dsa_switch_ops {
>  					  const struct switchdev_obj_ring_role_mrp *mrp);
>  	int	(*port_mrp_del_ring_role)(struct dsa_switch *ds, int port,
>  					  const struct switchdev_obj_ring_role_mrp *mrp);
> +
> +	/* L2 forward offloading */
> +	void *	(*dfwd_add_station)(struct dsa_switch *ds, int port,
> +				    struct net_device *sb_dev);
> +	void	(*dfwd_del_station)(struct dsa_switch *ds, int port,
> +				    struct net_device *sb_dev);
>  };
>  
>  #define DSA_DEVLINK_PARAM_DRIVER(_id, _name, _type, _cmodes)		\
> diff --git a/net/dsa/slave.c b/net/dsa/slave.c
> index 77b33bd161b8..3689ffa2dbb8 100644
> --- a/net/dsa/slave.c
> +++ b/net/dsa/slave.c
> @@ -657,6 +657,13 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb,
struct net_device *dev)
>  	return dsa_enqueue_skb(nskb, dev);
>  }
>  
> +static u16 dsa_slave_select_queue(struct net_device *dev, struct sk_buff
*skb,
> +				  struct net_device *sb_dev)
> +{
> +	DSA_SKB_CB(skb)->sb_dev = sb_dev;
> +	return netdev_pick_tx(dev, skb, sb_dev);
> +}
> +
DSA_SKB_CB is going away:
https://patchwork.kernel.org/project/netdevbpf/patch/20210427042203.26258-5-yangbo.lu
at nxp.com/

Let's either negotiate with Yangbo on keeping it, or make
.ndo_select_queue a bypass towards the tagger, where it can use its own
SKB_CB structure and be more flexible in general (I think I'm leaning
towards the latter).

Tobias Waldekranz

2021-May-04 14:44 UTC

head link

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

On Tue, Apr 27, 2021 at 13:17, Vladimir Oltean <olteanv at gmail.com>
wrote:> On Mon, Apr 26, 2021 at 07:04:08PM +0200, Tobias Waldekranz wrote:
>> Allow DSA drivers to support forward offloading from a bridge by:
>> 
>> - Passing calls to .ndo_dfwd_{add,del}_station to the drivers.
>> 
>> - Recording the subordinate device of offloaded skbs in the control
>>   buffer so that the tagger can take the appropriate action.
>> 
>> Signed-off-by: Tobias Waldekranz <tobias at waldekranz.com>
>> ---
>>  include/net/dsa.h |  7 +++++++
>>  net/dsa/slave.c   | 36 ++++++++++++++++++++++++++++++++++--
>>  2 files changed, 41 insertions(+), 2 deletions(-)
>> 
>> diff --git a/include/net/dsa.h b/include/net/dsa.h
>> index 1f9ba9889034..77d4df819299 100644
>> --- a/include/net/dsa.h
>> +++ b/include/net/dsa.h
>> @@ -119,6 +119,7 @@ struct dsa_netdevice_ops {
>>  
>>  struct dsa_skb_cb {
>>  	struct sk_buff *clone;
>> +	struct net_device *sb_dev;
>>  };
>>  
>>  struct __dsa_skb_cb {
>> @@ -828,6 +829,12 @@ struct dsa_switch_ops {
>>  					  const struct switchdev_obj_ring_role_mrp *mrp);
>>  	int	(*port_mrp_del_ring_role)(struct dsa_switch *ds, int port,
>>  					  const struct switchdev_obj_ring_role_mrp *mrp);
>> +
>> +	/* L2 forward offloading */
>> +	void *	(*dfwd_add_station)(struct dsa_switch *ds, int port,
>> +				    struct net_device *sb_dev);
>> +	void	(*dfwd_del_station)(struct dsa_switch *ds, int port,
>> +				    struct net_device *sb_dev);
>>  };
>>  
>>  #define DSA_DEVLINK_PARAM_DRIVER(_id, _name, _type, _cmodes)		\
>> diff --git a/net/dsa/slave.c b/net/dsa/slave.c
>> index 77b33bd161b8..3689ffa2dbb8 100644
>> --- a/net/dsa/slave.c
>> +++ b/net/dsa/slave.c
>> @@ -657,6 +657,13 @@ static netdev_tx_t dsa_slave_xmit(struct sk_buff
*skb, struct net_device *dev)
>>  	return dsa_enqueue_skb(nskb, dev);
>>  }
>>  
>> +static u16 dsa_slave_select_queue(struct net_device *dev, struct
sk_buff *skb,
>> +				  struct net_device *sb_dev)
>> +{
>> +	DSA_SKB_CB(skb)->sb_dev = sb_dev;
>> +	return netdev_pick_tx(dev, skb, sb_dev);
>> +}
>> +
>
> DSA_SKB_CB is going away:
>
https://patchwork.kernel.org/project/netdevbpf/patch/20210427042203.26258-5-yangbo.lu
at nxp.com/
>
> Let's either negotiate with Yangbo on keeping it, or make
> .ndo_select_queue a bypass towards the tagger, where it can use its own
> SKB_CB structure and be more flexible in general (I think I'm leaning
> towards the latter).
Thus far, Yangbo is a tough negotiator, giving me the silent treatment:

https://lore.kernel.org/netdev/87y2d2noe5.fsf at waldekranz.com/

:)

That memset is giving me a hard time. I have just disabled it on my
branch at the moment. Any ideas on how to get rid of it without breaking
timestamping?

Linux Ethernet Bridging - May 2021 - [Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading

[Bridge] [RFC net-next 6/9] net: dsa: Forward offloading