# Re: \[PATCH net-next v12 1/5\] net: Introduce generic failover module

- From: Stephen Hemminger \<stephen@networkplumber.org\>
- Date: 2018-05-25 22:37:47 
- List: netdev
- Page: https://ratatoskr.run/netdev/2018/05/11097380
- Thread: https://ratatoskr.run/netdev/2018/05/11097172/t.md

```text
On Thu, 24 May 2018 09:55:13 -0700
Sridhar Samudrala [ref] wrote:


> +	spin_lock(&failover_lock);

Since register is not in fast path, this should be a mutex?


> +int failover_slave_unregister(struct net_device *slave_dev)
> +{
> +	struct net_device *failover_dev;
> +	struct failover_ops *fops;
> +
> +	if (!netif_is_failover_slave(slave_dev))
> +		goto done;
> +
> +	ASSERT_RTNL();
> +
> +	failover_dev = failover_get_bymac(slave_dev->perm_addr, &fops);
> +	if (!failover_dev)
> +		goto done;

Since the slave device must have a master device set already, why not use
that instead of searching by MAC address on unregister or link change.
```