Re: [Bridge] [PATCH net-next v3 7/8] net: switchdev: Replace port attr set SDO with a notification

[Ido Schimmel <idosch@mellanox.com>]

On Wed, Feb 27, 2019 at 11:44:31AM -0800, Florian Fainelli wrote:
> Drop switchdev_ops.switchdev_port_attr_set. Drop the uses of this field
> from all clients, which were migrated to use switchdev notification in
> the previous patches.
> 
> Add a new function switchdev_port_attr_notify() that sends the switchdev
> notifications SWITCHDEV_PORT_ATTR_SET and calls the blocking (process)
> notifier chain.
> 
> We have one odd case within net/bridge/br_switchdev.c with the
> SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS attribute identifier that
> requires executing from atomic context, we deal with that one
> specifically.
> 
> Drop __switchdev_port_attr_set() and update switchdev_port_attr_set()
> likewise.
> 
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Reviewed-by: Ido Schimmel <idosch@mellanox.com>

One small nit that you can address in a follow-up:

> @@ -67,12 +67,18 @@ int br_switchdev_set_port_flag(struct net_bridge_port *p,
>  		.id = SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS,
>  		.u.brport_flags = mask,
>  	};
> +	struct switchdev_notifier_port_attr_info info = {
> +		.attr = &attr,
> +	};
>  	int err;
>  
>  	if (mask & ~BR_PORT_FLAGS_HW_OFFLOAD)
>  		return 0;
>  
> -	err = switchdev_port_attr_set(p->dev, &attr);
> +	/* We run from atomic context here */
> +	err = call_switchdev_notifiers(SWITCHDEV_PORT_ATTR_SET, p->dev,
> +				       &info.info, NULL);
> +	err = notifier_to_errno(err);
>  	if (err == -EOPNOTSUPP)
>  		return 0;

This check can be removed. The code below checks `err` and fails the
operation in case of error.