Subject: Re: [PATCH -next] net/hsr: using kfree_rcu() to simplify the code

From: Arvid Brodin <[email-masked]>
Date: Tue, 17 Dec 2013 01:56:01 +0100

Looks good to me, feel free to add 

Acked-by: Arvid Brodin <[email-masked]>

Nice to have others look at the code! :)

On 2013-12-16 07:05, Wei Yongjun wrote:
> From: Wei Yongjun <[email-masked]>
> 
> The callback function of call_rcu() just calls a kfree(), so we
> can use kfree_rcu() instead of call_rcu() + callback function.
> 
> Signed-off-by: Wei Yongjun <[email-masked]>
> ---
>  net/hsr/hsr_framereg.c | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
> 
> diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
> index 003f5bb..a758963 100644
> --- a/net/hsr/hsr_framereg.c
> +++ b/net/hsr/hsr_framereg.c
> @@ -127,11 +127,6 @@ int hsr_create_self_node(struct list_head *self_node_db,
>  	return 0;
>  }
>  
> -static void node_entry_reclaim(struct rcu_head *rh)
> -{
> -	kfree(container_of(rh, struct node_entry, rcu_head));
> -}
> -
>  
>  /* Add/merge node to the database of nodes. 'skb' must contain an HSR
>   * supervision frame.
> @@ -175,7 +170,7 @@ struct node_entry *hsr_merge_node(struct hsr_priv *hsr_priv,
>  	if (node && !ether_addr_equal(node->MacAddressA, hsr_sp->MacAddressA)) {
>  		/* Node has changed its AddrA, frame was received from SlaveB */
>  		list_del_rcu(&node->mac_list);
> -		call_rcu(&node->rcu_head, node_entry_reclaim);
> +		kfree_rcu(node, rcu_head);
>  		node = NULL;
>  	}
>  
> @@ -183,7 +178,7 @@ struct node_entry *hsr_merge_node(struct hsr_priv *hsr_priv,
>  	    !ether_addr_equal(node->MacAddressB, hsr_ethsup->ethhdr.h_source)) {
>  		/* Cables have been swapped */
>  		list_del_rcu(&node->mac_list);
> -		call_rcu(&node->rcu_head, node_entry_reclaim);
> +		kfree_rcu(node, rcu_head);
>  		node = NULL;
>  	}
>  
> @@ -192,7 +187,7 @@ struct node_entry *hsr_merge_node(struct hsr_priv *hsr_priv,
>  	    !ether_addr_equal(node->MacAddressA, hsr_ethsup->ethhdr.h_source)) {
>  		/* Cables have been swapped */
>  		list_del_rcu(&node->mac_list);
> -		call_rcu(&node->rcu_head, node_entry_reclaim);
> +		kfree_rcu(node, rcu_head);
>  		node = NULL;
>  	}
>  
> @@ -416,7 +411,7 @@ void hsr_prune_nodes(struct hsr_priv *hsr_priv)
>  			hsr_nl_nodedown(hsr_priv, node->MacAddressA);
>  			list_del_rcu(&node->mac_list);
>  			/* Note that we need to free this entry later: */
> -			call_rcu(&node->rcu_head, node_entry_reclaim);
> +			kfree_rcu(node, rcu_head);
>  		}
>  	}
>  	rcu_read_unlock();
> 

-- 
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