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[net-next,0/5] net: dsa: mv88e6xxx: Offload bridge port flags

Message ID 20210315211400.2805330-1-tobias@waldekranz.com
Headers show
Series net: dsa: mv88e6xxx: Offload bridge port flags | expand

Message

Tobias Waldekranz March 15, 2021, 9:13 p.m. UTC
Add support for offloading learning and broadcast flooding flags. With
this in place, mv88e6xx supports offloading of all bridge port flags
that are currently supported by the bridge.

Broadcast flooding is somewhat awkward to control as there is no
per-port bit for this like there is for unknown unicast and unknown
multicast. Instead we have to update the ATU entry for the broadcast
address for all currently used FIDs.

Tobias Waldekranz (5):
  net: dsa: mv88e6xxx: Provide generic VTU iterator
  net: dsa: mv88e6xxx: Remove some bureaucracy around querying the VTU
  net: dsa: mv88e6xxx: Flood all traffic classes on standalone ports
  net: dsa: mv88e6xxx: Offload bridge learning flag
  net: dsa: mv88e6xxx: Offload bridge broadcast flooding flag

 drivers/net/dsa/mv88e6xxx/chip.c | 248 +++++++++++++++++++++----------
 drivers/net/dsa/mv88e6xxx/port.c |  21 +++
 drivers/net/dsa/mv88e6xxx/port.h |   2 +
 3 files changed, 196 insertions(+), 75 deletions(-)

Comments

Vladimir Oltean March 16, 2021, 8:42 a.m. UTC | #1
On Mon, Mar 15, 2021 at 10:13:56PM +0100, Tobias Waldekranz wrote:
> @@ -2184,25 +2230,7 @@ static int mv88e6xxx_port_db_dump(struct mv88e6xxx_chip *chip, int port,

>  	if (err)

>  		return err;

>  

> -	/* Dump VLANs' Filtering Information Databases */

> -	vlan.vid = mv88e6xxx_max_vid(chip);

> -	vlan.valid = false;

> -

> -	do {

> -		err = mv88e6xxx_vtu_getnext(chip, &vlan);

> -		if (err)

> -			return err;

> -

> -		if (!vlan.valid)

> -			break;

> -

> -		err = mv88e6xxx_port_db_dump_fid(chip, vlan.fid, vlan.vid, port,

> -						 cb, data);

> -		if (err)

> -			return err;

> -	} while (vlan.vid < mv88e6xxx_max_vid(chip));

> -

> -	return err;

> +	return mv88e6xxx_vtu_walk(chip, mv88e6xxx_port_db_dump_vlan, &ctx);

>  }


Can the mv88e6xxx_port_db_dump_fid(VLAN 0) located above this call be
covered by the same mv88e6xxx_vtu_walk?
Vladimir Oltean March 16, 2021, 9:17 a.m. UTC | #2
On Mon, Mar 15, 2021 at 10:13:57PM +0100, Tobias Waldekranz wrote:
> +static int mv88e6xxx_vtu_get(struct mv88e6xxx_chip *chip, u16 vid,

> +			     struct mv88e6xxx_vtu_entry *entry)

>  {

> +	int err;

> +

>  	if (!chip->info->ops->vtu_getnext)

>  		return -EOPNOTSUPP;

>  

> -	return chip->info->ops->vtu_getnext(chip, entry);

> +	entry->vid = vid - 1;


Should the vtu_get API not work with vid 0 as well? Shouldn't we
initialize entry->vid to mv88e6xxx_max_vid(chip) in that case?

> +	entry->valid = false;

> +

> +	err = chip->info->ops->vtu_getnext(chip, entry);

> +

> +	if (entry->vid != vid)

> +		entry->valid = false;

> +

> +	return err;

>  }
Vladimir Oltean March 16, 2021, 9:39 a.m. UTC | #3
On Mon, Mar 15, 2021 at 10:14:00PM +0100, Tobias Waldekranz wrote:
> These switches have two modes of classifying broadcast:

> 

> 1. Broadcast is multicast.

> 2. Broadcast is its own unique thing that is always flooded

>    everywhere.

> 

> This driver uses the first option, making sure to load the broadcast

> address into all active databases. Because of this, we can support

> per-port broadcast flooding by (1) making sure to only set the subset

> of ports that have it enabled whenever joining a new bridge or VLAN,

> and (2) by updating all active databases whenever the setting is

> changed on a port.

> 

> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>

> ---

>  drivers/net/dsa/mv88e6xxx/chip.c | 68 +++++++++++++++++++++++++++++++-

>  1 file changed, 67 insertions(+), 1 deletion(-)

> 

> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c

> index 48e65f22641e..e6987c501fb7 100644

> --- a/drivers/net/dsa/mv88e6xxx/chip.c

> +++ b/drivers/net/dsa/mv88e6xxx/chip.c

> @@ -1950,6 +1950,18 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

>  	int err;

>  

>  	for (port = 0; port < mv88e6xxx_num_ports(chip); port++) {

> +		struct dsa_port *dp = dsa_to_port(chip->ds, port);

> +

> +		if (dsa_is_unused_port(chip->ds, port))

> +			continue;

> +

> +		if (dsa_is_user_port(chip->ds, port) && dp->bridge_dev &&

> +		    !br_port_flag_is_set(dp->slave, BR_BCAST_FLOOD))


What if dp->slave is not the bridge port, but a LAG? br_port_flag_is_set
will return false.

Speaking of, shouldn't mv88e6xxx_port_vlan_join also be called from
mv88e6xxx_port_bridge_join somehow, or are we waiting for the bridge
facility to replay VLANs added to the LAG when we emit the offload
notification for it?

> +			/* Skip bridged user ports where broadcast

> +			 * flooding is disabled.

> +			 */

> +			continue;

> +

>  		err = mv88e6xxx_port_add_broadcast(chip, port, vid);

>  		if (err)

>  			return err;

> @@ -1958,6 +1970,51 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

>  	return 0;

>  }

>  

> +struct mv88e6xxx_port_broadcast_sync_ctx {

> +	int port;

> +	bool flood;

> +};

> +

> +static int

> +mv88e6xxx_port_broadcast_sync_vlan(struct mv88e6xxx_chip *chip,

> +				   const struct mv88e6xxx_vtu_entry *vlan,

> +				   void *_ctx)

> +{

> +	const char broadcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };


MAC addresses are usually defined as unsigned char[ETH_ALEN]. You can
also use eth_broadcast_addr(broadcast) for initialization.

> +	struct mv88e6xxx_port_broadcast_sync_ctx *ctx = _ctx;

> +	u8 state;

> +

> +	if (ctx->flood)

> +		state = MV88E6XXX_G1_ATU_DATA_STATE_MC_STATIC;

> +	else

> +		state = MV88E6XXX_G1_ATU_DATA_STATE_MC_UNUSED;

> +

> +	return mv88e6xxx_port_db_load_purge(chip, ctx->port, broadcast,

> +					    vlan->vid, state);

> +}

> +

> +static int mv88e6xxx_port_broadcast_sync(struct mv88e6xxx_chip *chip, int port,

> +					 bool flood)

> +{

> +	struct mv88e6xxx_port_broadcast_sync_ctx ctx = {

> +		.port = port,

> +		.flood = flood,

> +	};

> +	struct mv88e6xxx_vtu_entry vid0 = {

> +		.vid = 0,

> +	};

> +	int err;

> +

> +	/* Update the port's private database... */

> +	err = mv88e6xxx_port_broadcast_sync_vlan(chip, &vid0, &ctx);

> +	if (err)

> +		return err;

> +

> +	/* ...and the database for all VLANs. */

> +	return mv88e6xxx_vtu_walk(chip, mv88e6xxx_port_broadcast_sync_vlan,

> +				  &ctx);

> +}

> +

>  static int mv88e6xxx_port_vlan_join(struct mv88e6xxx_chip *chip, int port,

>  				    u16 vid, u8 member, bool warn)

>  {

> @@ -5431,7 +5488,8 @@ static int mv88e6xxx_port_pre_bridge_flags(struct dsa_switch *ds, int port,

>  	struct mv88e6xxx_chip *chip = ds->priv;

>  	const struct mv88e6xxx_ops *ops;

>  

> -	if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD))

> +	if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |

> +			   BR_BCAST_FLOOD))

>  		return -EINVAL;

>  

>  	ops = chip->info->ops;

> @@ -5480,6 +5538,14 @@ static int mv88e6xxx_port_bridge_flags(struct dsa_switch *ds, int port,

>  			goto out;

>  	}

>  

> +	if (flags.mask & BR_BCAST_FLOOD) {

> +		bool broadcast = !!(flags.val & BR_BCAST_FLOOD);

> +

> +		err = mv88e6xxx_port_broadcast_sync(chip, port, broadcast);

> +		if (err)

> +			goto out;

> +	}

> +

>  out:

>  	mv88e6xxx_reg_unlock(chip);

>  

> -- 

> 2.25.1

>
Tobias Waldekranz March 17, 2021, 9:41 a.m. UTC | #4
On Tue, Mar 16, 2021 at 10:42, Vladimir Oltean <olteanv@gmail.com> wrote:
> On Mon, Mar 15, 2021 at 10:13:56PM +0100, Tobias Waldekranz wrote:

>> @@ -2184,25 +2230,7 @@ static int mv88e6xxx_port_db_dump(struct mv88e6xxx_chip *chip, int port,

>>  	if (err)

>>  		return err;

>>  

>> -	/* Dump VLANs' Filtering Information Databases */

>> -	vlan.vid = mv88e6xxx_max_vid(chip);

>> -	vlan.valid = false;

>> -

>> -	do {

>> -		err = mv88e6xxx_vtu_getnext(chip, &vlan);

>> -		if (err)

>> -			return err;

>> -

>> -		if (!vlan.valid)

>> -			break;

>> -

>> -		err = mv88e6xxx_port_db_dump_fid(chip, vlan.fid, vlan.vid, port,

>> -						 cb, data);

>> -		if (err)

>> -			return err;

>> -	} while (vlan.vid < mv88e6xxx_max_vid(chip));

>> -

>> -	return err;

>> +	return mv88e6xxx_vtu_walk(chip, mv88e6xxx_port_db_dump_vlan, &ctx);

>>  }

>

> Can the mv88e6xxx_port_db_dump_fid(VLAN 0) located above this call be

> covered by the same mv88e6xxx_vtu_walk?


The port's default default FID does not belong to any VLAN, so it is
never loaded in the VTU. That is why it handled separately. So, no :)
Tobias Waldekranz March 17, 2021, 9:46 a.m. UTC | #5
On Tue, Mar 16, 2021 at 11:17, Vladimir Oltean <olteanv@gmail.com> wrote:
> On Mon, Mar 15, 2021 at 10:13:57PM +0100, Tobias Waldekranz wrote:

>> +static int mv88e6xxx_vtu_get(struct mv88e6xxx_chip *chip, u16 vid,

>> +			     struct mv88e6xxx_vtu_entry *entry)

>>  {

>> +	int err;

>> +

>>  	if (!chip->info->ops->vtu_getnext)

>>  		return -EOPNOTSUPP;

>>  

>> -	return chip->info->ops->vtu_getnext(chip, entry);

>> +	entry->vid = vid - 1;

>

> Should the vtu_get API not work with vid 0 as well? Shouldn't we

> initialize entry->vid to mv88e6xxx_max_vid(chip) in that case?


Good catch. We never load VID 0 to the VTU today, but this function
should be ready for it, if that ever changes. Fixing in v2.

>> +	entry->valid = false;

>> +

>> +	err = chip->info->ops->vtu_getnext(chip, entry);

>> +

>> +	if (entry->vid != vid)

>> +		entry->valid = false;

>> +

>> +	return err;

>>  }
Tobias Waldekranz March 17, 2021, 11:14 a.m. UTC | #6
On Tue, Mar 16, 2021 at 11:39, Vladimir Oltean <olteanv@gmail.com> wrote:
> On Mon, Mar 15, 2021 at 10:14:00PM +0100, Tobias Waldekranz wrote:

>> These switches have two modes of classifying broadcast:

>> 

>> 1. Broadcast is multicast.

>> 2. Broadcast is its own unique thing that is always flooded

>>    everywhere.

>> 

>> This driver uses the first option, making sure to load the broadcast

>> address into all active databases. Because of this, we can support

>> per-port broadcast flooding by (1) making sure to only set the subset

>> of ports that have it enabled whenever joining a new bridge or VLAN,

>> and (2) by updating all active databases whenever the setting is

>> changed on a port.

>> 

>> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>

>> ---

>>  drivers/net/dsa/mv88e6xxx/chip.c | 68 +++++++++++++++++++++++++++++++-

>>  1 file changed, 67 insertions(+), 1 deletion(-)

>> 

>> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c

>> index 48e65f22641e..e6987c501fb7 100644

>> --- a/drivers/net/dsa/mv88e6xxx/chip.c

>> +++ b/drivers/net/dsa/mv88e6xxx/chip.c

>> @@ -1950,6 +1950,18 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

>>  	int err;

>>  

>>  	for (port = 0; port < mv88e6xxx_num_ports(chip); port++) {

>> +		struct dsa_port *dp = dsa_to_port(chip->ds, port);

>> +

>> +		if (dsa_is_unused_port(chip->ds, port))

>> +			continue;

>> +

>> +		if (dsa_is_user_port(chip->ds, port) && dp->bridge_dev &&

>> +		    !br_port_flag_is_set(dp->slave, BR_BCAST_FLOOD))

>

> What if dp->slave is not the bridge port, but a LAG? br_port_flag_is_set

> will return false.


Good point. I see two ways forward:

- My first idea was to cache a vector per switch that would act as the
  template when creating a new entry. This avoids having the driver
  layer knowing about stacked netdevs etc. But I think that Andrew is
  generally opposed to caching?

- Add a new helper at the dsa layer that takes a dp and returns the
  netdev that is attached to the bridge, if any:

  struct net_device *dsa_port_to_bridge_port(struct dsa_port *dp)

Any preference or other ideas?

> Speaking of, shouldn't mv88e6xxx_port_vlan_join also be called from

> mv88e6xxx_port_bridge_join somehow, or are we waiting for the bridge

> facility to replay VLANs added to the LAG when we emit the offload

> notification for it?


I do not think so. VLANs are always added via the .port_vlan_add
callback, no?

Potentially the bridge is of the non-filtering variety, so it could be
that no VLANs are ever added.

Or do you mean (the most confusingly named feature Marvell LinkStreet
devices) port-based VLANs? Those are setup on a bridge join via
mv88e6xxx_port_vlan_map and mv88e6xxx_pvt_map.

>> +			/* Skip bridged user ports where broadcast

>> +			 * flooding is disabled.

>> +			 */

>> +			continue;

>> +

>>  		err = mv88e6xxx_port_add_broadcast(chip, port, vid);

>>  		if (err)

>>  			return err;

>> @@ -1958,6 +1970,51 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

>>  	return 0;

>>  }

>>  

>> +struct mv88e6xxx_port_broadcast_sync_ctx {

>> +	int port;

>> +	bool flood;

>> +};

>> +

>> +static int

>> +mv88e6xxx_port_broadcast_sync_vlan(struct mv88e6xxx_chip *chip,

>> +				   const struct mv88e6xxx_vtu_entry *vlan,

>> +				   void *_ctx)

>> +{

>> +	const char broadcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

>

> MAC addresses are usually defined as unsigned char[ETH_ALEN]. You can

> also use eth_broadcast_addr(broadcast) for initialization.


I was going for uniformity with mv88e6xxx_port_add_broadcast. But I will
add a clean-up commit that fixes the existing code first, and then adds
this definition in the proper way.

>> +	struct mv88e6xxx_port_broadcast_sync_ctx *ctx = _ctx;

>> +	u8 state;

>> +

>> +	if (ctx->flood)

>> +		state = MV88E6XXX_G1_ATU_DATA_STATE_MC_STATIC;

>> +	else

>> +		state = MV88E6XXX_G1_ATU_DATA_STATE_MC_UNUSED;

>> +

>> +	return mv88e6xxx_port_db_load_purge(chip, ctx->port, broadcast,

>> +					    vlan->vid, state);

>> +}

>> +

>> +static int mv88e6xxx_port_broadcast_sync(struct mv88e6xxx_chip *chip, int port,

>> +					 bool flood)

>> +{

>> +	struct mv88e6xxx_port_broadcast_sync_ctx ctx = {

>> +		.port = port,

>> +		.flood = flood,

>> +	};

>> +	struct mv88e6xxx_vtu_entry vid0 = {

>> +		.vid = 0,

>> +	};

>> +	int err;

>> +

>> +	/* Update the port's private database... */

>> +	err = mv88e6xxx_port_broadcast_sync_vlan(chip, &vid0, &ctx);

>> +	if (err)

>> +		return err;

>> +

>> +	/* ...and the database for all VLANs. */

>> +	return mv88e6xxx_vtu_walk(chip, mv88e6xxx_port_broadcast_sync_vlan,

>> +				  &ctx);

>> +}

>> +

>>  static int mv88e6xxx_port_vlan_join(struct mv88e6xxx_chip *chip, int port,

>>  				    u16 vid, u8 member, bool warn)

>>  {

>> @@ -5431,7 +5488,8 @@ static int mv88e6xxx_port_pre_bridge_flags(struct dsa_switch *ds, int port,

>>  	struct mv88e6xxx_chip *chip = ds->priv;

>>  	const struct mv88e6xxx_ops *ops;

>>  

>> -	if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD))

>> +	if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |

>> +			   BR_BCAST_FLOOD))

>>  		return -EINVAL;

>>  

>>  	ops = chip->info->ops;

>> @@ -5480,6 +5538,14 @@ static int mv88e6xxx_port_bridge_flags(struct dsa_switch *ds, int port,

>>  			goto out;

>>  	}

>>  

>> +	if (flags.mask & BR_BCAST_FLOOD) {

>> +		bool broadcast = !!(flags.val & BR_BCAST_FLOOD);

>> +

>> +		err = mv88e6xxx_port_broadcast_sync(chip, port, broadcast);

>> +		if (err)

>> +			goto out;

>> +	}

>> +

>>  out:

>>  	mv88e6xxx_reg_unlock(chip);

>>  

>> -- 

>> 2.25.1

>>
Vladimir Oltean March 17, 2021, 11:24 a.m. UTC | #7
On Wed, Mar 17, 2021 at 12:14:18PM +0100, Tobias Waldekranz wrote:
> Good point. I see two ways forward:

> 

> - My first idea was to cache a vector per switch that would act as the

>   template when creating a new entry. This avoids having the driver

>   layer knowing about stacked netdevs etc. But I think that Andrew is

>   generally opposed to caching?

> 

> - Add a new helper at the dsa layer that takes a dp and returns the

>   netdev that is attached to the bridge, if any:

> 

>   struct net_device *dsa_port_to_bridge_port(struct dsa_port *dp)

> 

> Any preference or other ideas?


I vote for dsa_port_to_bridge_port. We'll need it anyway for my software
bridging series with sandwiched net devices.

> > Speaking of, shouldn't mv88e6xxx_port_vlan_join also be called from

> > mv88e6xxx_port_bridge_join somehow, or are we waiting for the bridge

> > facility to replay VLANs added to the LAG when we emit the offload

> > notification for it?

> 

> I do not think so. VLANs are always added via the .port_vlan_add

> callback, no?


I got things mixed up in my head while thinking about it.
Yes, of course, the bridge pvid is added via .port_vlan_add as soon as
the port joins the bridge.
What I meant to say is that this sequence of events:

ip link add br0 type bridge
ip link add bond0 type bonding
ip link set bond0 master br0
ip link set lan0 master bond0

will cause lan0 to miss all sorts of information about the bridge port
switchdev objects, including the pvid. My patch series for
SWITCHDEV_BRPORT_OFFLOADED catches this case and asks for a replay.

> Potentially the bridge is of the non-filtering variety, so it could be

> that no VLANs are ever added.


That will not happen unless you set ds->configure_vlan_while_not_filtering = false,
which mv88e6xxx no longer does, so we're in the clear.

> Or do you mean (the most confusingly named feature Marvell LinkStreet

> devices) port-based VLANs? Those are setup on a bridge join via

> mv88e6xxx_port_vlan_map and mv88e6xxx_pvt_map.


Nope, I wasn't thinking about PVTs.

> >> +			/* Skip bridged user ports where broadcast

> >> +			 * flooding is disabled.

> >> +			 */

> >> +			continue;

> >> +

> >>  		err = mv88e6xxx_port_add_broadcast(chip, port, vid);

> >>  		if (err)

> >>  			return err;

> >> @@ -1958,6 +1970,51 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

> >>  	return 0;

> >>  }

> >>  

> >> +struct mv88e6xxx_port_broadcast_sync_ctx {

> >> +	int port;

> >> +	bool flood;

> >> +};

> >> +

> >> +static int

> >> +mv88e6xxx_port_broadcast_sync_vlan(struct mv88e6xxx_chip *chip,

> >> +				   const struct mv88e6xxx_vtu_entry *vlan,

> >> +				   void *_ctx)

> >> +{

> >> +	const char broadcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

> >

> > MAC addresses are usually defined as unsigned char[ETH_ALEN]. You can

> > also use eth_broadcast_addr(broadcast) for initialization.

> 

> I was going for uniformity with mv88e6xxx_port_add_broadcast. But I will

> add a clean-up commit that fixes the existing code first, and then adds

> this definition in the proper way.


Thanks.
Andrew Lunn March 18, 2021, 1:50 a.m. UTC | #8
On Wed, Mar 17, 2021 at 12:14:18PM +0100, Tobias Waldekranz wrote:
> On Tue, Mar 16, 2021 at 11:39, Vladimir Oltean <olteanv@gmail.com> wrote:

> > On Mon, Mar 15, 2021 at 10:14:00PM +0100, Tobias Waldekranz wrote:

> >> These switches have two modes of classifying broadcast:

> >> 

> >> 1. Broadcast is multicast.

> >> 2. Broadcast is its own unique thing that is always flooded

> >>    everywhere.

> >> 

> >> This driver uses the first option, making sure to load the broadcast

> >> address into all active databases. Because of this, we can support

> >> per-port broadcast flooding by (1) making sure to only set the subset

> >> of ports that have it enabled whenever joining a new bridge or VLAN,

> >> and (2) by updating all active databases whenever the setting is

> >> changed on a port.

> >> 

> >> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>

> >> ---

> >>  drivers/net/dsa/mv88e6xxx/chip.c | 68 +++++++++++++++++++++++++++++++-

> >>  1 file changed, 67 insertions(+), 1 deletion(-)

> >> 

> >> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c

> >> index 48e65f22641e..e6987c501fb7 100644

> >> --- a/drivers/net/dsa/mv88e6xxx/chip.c

> >> +++ b/drivers/net/dsa/mv88e6xxx/chip.c

> >> @@ -1950,6 +1950,18 @@ static int mv88e6xxx_broadcast_setup(struct mv88e6xxx_chip *chip, u16 vid)

> >>  	int err;

> >>  

> >>  	for (port = 0; port < mv88e6xxx_num_ports(chip); port++) {

> >> +		struct dsa_port *dp = dsa_to_port(chip->ds, port);

> >> +

> >> +		if (dsa_is_unused_port(chip->ds, port))

> >> +			continue;

> >> +

> >> +		if (dsa_is_user_port(chip->ds, port) && dp->bridge_dev &&

> >> +		    !br_port_flag_is_set(dp->slave, BR_BCAST_FLOOD))

> >

> > What if dp->slave is not the bridge port, but a LAG? br_port_flag_is_set

> > will return false.

> 

> Good point. I see two ways forward:

> 

> - My first idea was to cache a vector per switch that would act as the

>   template when creating a new entry. This avoids having the driver

>   layer knowing about stacked netdevs etc. But I think that Andrew is

>   generally opposed to caching?


Hi Tobias

What i'm mostly against is dynamic memory allocation. If you can
allocate the space for this vector during probe, i have no problems
with that.

     Andrew