Re: [PATCH] net: ipv4: route.c: Remove unnecessary {else} if()

2021-03-23 Thread David Ahern
subject line should have net-next as the target branch


On 3/23/21 4:20 AM, Yejune Deng wrote:
> Put if and else if together, and remove unnecessary judgments, because
> it's caller can make sure it is true. And add likely() in
> ipv4_confirm_neigh().
> 
> Signed-off-by: Yejune Deng 
> ---
>  net/ipv4/route.c | 18 +++---
>  1 file changed, 7 insertions(+), 11 deletions(-)
> 
> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
> index fa68c2612252..f4ba07c5c1b1 100644
> --- a/net/ipv4/route.c
> +++ b/net/ipv4/route.c
> @@ -440,7 +440,7 @@ static void ipv4_confirm_neigh(const struct dst_entry 
> *dst, const void *daddr)
>   struct net_device *dev = dst->dev;
>   const __be32 *pkey = daddr;
>  
> - if (rt->rt_gw_family == AF_INET) {
> + if (likely(rt->rt_gw_family == AF_INET)) {
>   pkey = (const __be32 *)>rt_gw4;
>   } else if (rt->rt_gw_family == AF_INET6) {
>   return __ipv6_confirm_neigh_stub(dev, >rt_gw6);
> @@ -814,19 +814,15 @@ static void ip_do_redirect(struct dst_entry *dst, 
> struct sock *sk, struct sk_buf
>  
>  static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
>  {
> - struct rtable *rt = (struct rtable *)dst;
> + struct rtable *rt = container_of(dst, struct rtable, dst);
>   struct dst_entry *ret = dst;
>  
> - if (rt) {
> - if (dst->obsolete > 0) {
> - ip_rt_put(rt);
> - ret = NULL;
> - } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
> -rt->dst.expires) {
> - ip_rt_put(rt);
> - ret = NULL;
> - }
> + if (dst->obsolete > 0 || rt->dst.expires ||
> + (rt->rt_flags & RTCF_REDIRECTED)) {
> + ip_rt_put(rt);
> + ret = NULL;
>   }
> +
>   return ret;
>  }
>  
> 

This should be 2 separate patches since they are unrelated changes.

For the ipv4_negative_advice, the changelog should note that
negative_advice handler is only called when dst is non-NULL hence the
'if (rt)' check can be removed.


[PATCH] net: ipv4: route.c: Remove unnecessary {else} if()

2021-03-23 Thread Yejune Deng
Put if and else if together, and remove unnecessary judgments, because
it's caller can make sure it is true. And add likely() in
ipv4_confirm_neigh().

Signed-off-by: Yejune Deng 
---
 net/ipv4/route.c | 18 +++---
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index fa68c2612252..f4ba07c5c1b1 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -440,7 +440,7 @@ static void ipv4_confirm_neigh(const struct dst_entry *dst, 
const void *daddr)
struct net_device *dev = dst->dev;
const __be32 *pkey = daddr;
 
-   if (rt->rt_gw_family == AF_INET) {
+   if (likely(rt->rt_gw_family == AF_INET)) {
pkey = (const __be32 *)>rt_gw4;
} else if (rt->rt_gw_family == AF_INET6) {
return __ipv6_confirm_neigh_stub(dev, >rt_gw6);
@@ -814,19 +814,15 @@ static void ip_do_redirect(struct dst_entry *dst, struct 
sock *sk, struct sk_buf
 
 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
 {
-   struct rtable *rt = (struct rtable *)dst;
+   struct rtable *rt = container_of(dst, struct rtable, dst);
struct dst_entry *ret = dst;
 
-   if (rt) {
-   if (dst->obsolete > 0) {
-   ip_rt_put(rt);
-   ret = NULL;
-   } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
-  rt->dst.expires) {
-   ip_rt_put(rt);
-   ret = NULL;
-   }
+   if (dst->obsolete > 0 || rt->dst.expires ||
+   (rt->rt_flags & RTCF_REDIRECTED)) {
+   ip_rt_put(rt);
+   ret = NULL;
}
+
return ret;
 }
 
-- 
2.29.0