Subject: Re: [RFC] [PATCH 5/5] net: Encapsulate inner code of __sk_dst_reset

From: Eric Dumazet <[email-masked]>
Date: Thu, 15 Oct 2009 11:53:30 +0200

Krishna Kumar a écrit :
> From: Krishna Kumar <[email-masked]>
> 
> Reuse code by adding ___sk_dst_reset() which is called by
> __sk_dst_reset() and __sk_dst_check(). This new API is also
> called from IPv6 to hide the internals of __sk_dst_reset
> and the setting of sk_tx_queue_mapping.
> 
> Signed-off-by: Krishna Kumar <[email-masked]>
> ---
>  include/net/sock.h               |   13 +++++++++----
>  net/core/sock.c                  |    4 +---
>  net/ipv6/inet6_connection_sock.c |    4 +---
>  3 files changed, 11 insertions(+), 10 deletions(-)
> 
> diff -ruNp org/include/net/sock.h new/include/net/sock.h
> --- org/include/net/sock.h	2009-10-14 18:00:17.000000000 +0530
> +++ new/include/net/sock.h	2009-10-14 18:00:30.000000000 +0530
> @@ -1186,17 +1186,22 @@ sk_dst_set(struct sock *sk, struct dst_e
>  }
>  
>  static inline void
> -__sk_dst_reset(struct sock *sk)
> +___sk_dst_reset(struct sock *sk, struct dst_entry *old_dst)
>  {
> -	struct dst_entry *old_dst;
> -
>  	sk_record_tx_queue(sk, -1);
> -	old_dst = sk->sk_dst_cache;
>  	sk->sk_dst_cache = NULL;
>  	dst_release(old_dst);
>  }
>  
>  static inline void
> +__sk_dst_reset(struct sock *sk)
> +{
> +	struct dst_entry *old_dst = sk->sk_dst_cache;
> +
> +	___sk_dst_reset(sk, old_dst);
> +}
> +
> +static inline void
>  sk_dst_reset(struct sock *sk)
>  {
>  	write_lock(&sk->sk_dst_lock);
> diff -ruNp org/net/core/sock.c new/net/core/sock.c
> --- org/net/core/sock.c	2009-10-14 18:00:22.000000000 +0530
> +++ new/net/core/sock.c	2009-10-14 18:00:30.000000000 +0530
> @@ -364,9 +364,7 @@ struct dst_entry *__sk_dst_check(struct 
>  	struct dst_entry *dst = sk->sk_dst_cache;
>  
>  	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
> -		sk_record_tx_queue(sk, -1);
> -		sk->sk_dst_cache = NULL;
> -		dst_release(dst);
> +		___sk_dst_reset(sk, dst);
>  		return NULL;
>  	}
>  
> diff -ruNp org/net/ipv6/inet6_connection_sock.c new/net/ipv6/inet6_connection_sock.c
> --- org/net/ipv6/inet6_connection_sock.c	2009-10-14 18:00:17.000000000 +0530
> +++ new/net/ipv6/inet6_connection_sock.c	2009-10-14 18:00:30.000000000 +0530
> @@ -168,9 +168,7 @@ struct dst_entry *__inet6_csk_dst_check(
>  	if (dst) {
>  		struct rt6_info *rt = (struct rt6_info *)dst;
>  		if (rt->rt6i_flow_cache_genid != atomic_read(&flow_cache_genid)) {
> -			sk_record_tx_queue(sk, -1);
> -			sk->sk_dst_cache = NULL;
> -			dst_release(dst);
> +			___sk_dst_reset(sk, dst);
>  			dst = NULL;
>  		}
>  	}
> 
> 

Encapsulation seems un-necessary to me, since only use cases are
___sk_dst_reset(sk, sk->sk_dst_cache)

static inline void __sk_dst_reset(struct sock *sk)
{
	struct dst_entry *old_dst = sk->sk_dst_cache;

	sk_record_tx_queue(sk, -1);
  	sk->sk_dst_cache = NULL;
 	dst_release(old_dst);
}