[PATCH net-next] ipv6: addrconf: don't evaluate keep_addr_on_down twice

[PATCH net-next] ipv6: addrconf: don't evaluate keep_addr_on_down twice

[Ivan Vecera]

The addrconf_ifdown() evaluates keep_addr_on_down state twice. There
is no need to do it.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Ivan Vecera <cera@cera.cz>
---
 net/ipv6/addrconf.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 78cef00c9596..f40e25fd15ee 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3612,8 +3612,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 	struct net *net = dev_net(dev);
 	struct inet6_dev *idev;
 	struct inet6_ifaddr *ifa, *tmp;
-	int _keep_addr;
-	bool keep_addr;
+	bool keep_addr = false;
 	int state, i;
 
 	ASSERT_RTNL();
@@ -3639,15 +3638,18 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 
 	}
 
-	/* aggregate the system setting and interface setting */
-	_keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
-	if (!_keep_addr)
-		_keep_addr = idev->cnf.keep_addr_on_down;
-
 	/* combine the user config with event to determine if permanent
 	 * addresses are to be removed from address hash table
 	 */
-	keep_addr = !(how || _keep_addr <= 0 || idev->cnf.disable_ipv6);
+	if (!how && !idev->cnf.disable_ipv6) {
+		/* aggregate the system setting and interface setting */
+		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
+
+		if (!_keep_addr)
+			_keep_addr = idev->cnf.keep_addr_on_down;
+
+		keep_addr = (_keep_addr > 0);
+	}
 
 	/* Step 2: clear hash table */
 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
@@ -3697,11 +3699,6 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 		write_lock_bh(&idev->lock);
 	}
 
-	/* re-combine the user config with event to determine if permanent
-	 * addresses are to be removed from the interface list
-	 */
-	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
-
 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
 		struct rt6_info *rt = NULL;
 		bool keep;
-- 
2.16.1

Re: [PATCH net-next] ipv6: addrconf: don't evaluate keep_addr_on_down twice

[David Ahern]

On 4/24/18 1:31 AM, Ivan Vecera wrote:
> The addrconf_ifdown() evaluates keep_addr_on_down state twice. There
> is no need to do it.
> 
> Cc: David Ahern <dsahern@gmail.com>
> Signed-off-by: Ivan Vecera <cera@cera.cz>
> ---
>  net/ipv6/addrconf.c | 23 ++++++++++-------------
>  1 file changed, 10 insertions(+), 13 deletions(-)

Looks right to me.

Acked-by: David Ahern <dsahern@gmail.com>

But  ...

> @@ -3697,11 +3699,6 @@ static int addrconf_ifdown(struct net_device *dev, int how)
>  		write_lock_bh(&idev->lock);
>  	}
>  
> -	/* re-combine the user config with event to determine if permanent
> -	 * addresses are to be removed from the interface list
> -	 */
> -	keep_addr = (!how && _keep_addr > 0 && !idev->cnf.disable_ipv6);
> -
>  	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
>  		struct rt6_info *rt = NULL;
>  		bool keep;
> 

you need to rebase to top of tree. That is 'struct fib6_info *rt' now so
the patch does not apply cleanly using git am.