Subject: Re: [PATCH net-next 09/10] can: use __dev_get_by_index instead of dev_get_by_index to find interface

From: Oliver Hartkopp <[email-masked]>
Date: Tue, 14 Jan 2014 17:11:26 +0100

On 14.01.2014 08:41, Ying Xue wrote:
> As cgw_create_job() is always under rtnl_lock protection,
> __dev_get_by_index() instead of dev_get_by_index() should be used to
> find interface handler in it having us avoid to change interface
> reference counter.
> 
> Cc: Oliver Hartkopp <[email-masked]>
> Signed-off-by: Ying Xue <[email-masked]>

Thanks for the simplification!

Acked-by: Oliver Hartkopp <[email-masked]>

> ---
>  net/can/gw.c |   15 +++++----------
>  1 file changed, 5 insertions(+), 10 deletions(-)
> 
> diff --git a/net/can/gw.c b/net/can/gw.c
> index 88c8a39..ac31891 100644
> --- a/net/can/gw.c
> +++ b/net/can/gw.c
> @@ -839,21 +839,21 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
>  	if (!gwj->ccgw.src_idx || !gwj->ccgw.dst_idx)
>  		goto out;
>  
> -	gwj->src.dev = dev_get_by_index(&init_net, gwj->ccgw.src_idx);
> +	gwj->src.dev = __dev_get_by_index(&init_net, gwj->ccgw.src_idx);
>  
>  	if (!gwj->src.dev)
>  		goto out;
>  
>  	if (gwj->src.dev->type != ARPHRD_CAN)
> -		goto put_src_out;
> +		goto out;
>  
> -	gwj->dst.dev = dev_get_by_index(&init_net, gwj->ccgw.dst_idx);
> +	gwj->dst.dev = __dev_get_by_index(&init_net, gwj->ccgw.dst_idx);
>  
>  	if (!gwj->dst.dev)
> -		goto put_src_out;
> +		goto out;
>  
>  	if (gwj->dst.dev->type != ARPHRD_CAN)
> -		goto put_src_dst_out;
> +		goto out;
>  
>  	gwj->limit_hops = limhops;
>  
> @@ -862,11 +862,6 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
>  	err = cgw_register_filter(gwj);
>  	if (!err)
>  		hlist_add_head_rcu(&gwj->list, &cgw_list);
> -
> -put_src_dst_out:
> -	dev_put(gwj->dst.dev);
> -put_src_out:
> -	dev_put(gwj->src.dev);
>  out:
>  	if (err)
>  		kmem_cache_free(cgw_cache, gwj);
>