Re: [PATCH tip/core/rcu 8/9] net/netfilter: Replace rcu_swap_protected() with rcu_replace()

[Pablo Neira Ayuso]

On Wed, Oct 02, 2019 at 06:43:09PM -0700, paulmck@xxxxxxxxxx wrote:
> From: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
> 
> This commit replaces the use of rcu_swap_protected() with the more
> intuitively appealing rcu_replace() as a step towards removing
> rcu_swap_protected().
> 
> Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@xxxxxxxxxxxxxx/
> Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> Cc: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
> Cc: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx>
> Cc: Florian Westphal <fw@xxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: <netfilter-devel@xxxxxxxxxxxxxxx>
> Cc: <coreteam@xxxxxxxxxxxxx>
> Cc: <netdev@xxxxxxxxxxxxxxx>

Acked-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>

> ---
>  net/netfilter/nf_tables_api.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
> index d481f9b..8499baf 100644
> --- a/net/netfilter/nf_tables_api.c
> +++ b/net/netfilter/nf_tables_api.c
> @@ -1461,8 +1461,9 @@ static void nft_chain_stats_replace(struct nft_trans *trans)
>  	if (!nft_trans_chain_stats(trans))
>  		return;
>  
> -	rcu_swap_protected(chain->stats, nft_trans_chain_stats(trans),
> -			   lockdep_commit_lock_is_held(trans->ctx.net));
> +	nft_trans_chain_stats(trans) =
> +		rcu_replace(chain->stats, nft_trans_chain_stats(trans),
> +			    lockdep_commit_lock_is_held(trans->ctx.net));
>  
>  	if (!nft_trans_chain_stats(trans))
>  		static_branch_inc(&nft_counters_enabled);
> -- 
> 2.9.5
>