Message-ID: <4774907D.5070806@cn.fujitsu.com>
Date: Fri, 28 Dec 2007 13:58:21 +0800
From: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
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To: David Miller <davem@davemloft.net>
CC: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: fib6_del_route has redundant code
References: <477353B6.6000102@cn.fujitsu.com> <20071227.211808.221171928.davem@davemloft.net>
In-Reply-To: <20071227.211808.221171928.davem@davemloft.net>
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>> I think the following code in fib6_del_route in the latest kernel is useless.
>> 1125         if (fn->leaf == NULL && fn->fn_flags&RTN_TL_ROOT)
>> 1126                 fn->leaf = &ip6_null_entry;
>>
>> ip6_null_entry will never be unlinked from fn->leaf now, that is,
>> fn->leaf == NULL will never meet.
> 
> I think you are right, but if it is true the next block of
> code is dead too:
> 
> 	/* If it was last route, expunge its radix tree node */
> 	if (fn->leaf == NULL) {
> 		fn->fn_flags &= ~RTN_RTINFO;
> 		rt6_stats.fib_route_nodes--;
> 		fn = fib6_repair_tree(fn);
> 	}
> 
Dave,

I think this block of code can't be removed, because just the root(default route)
fn->leaf always has ip6_null_entry on it. The normal fn->leaf becomes NULL when last
route has been deleted, the radix tree should be expunged.

> But I am not completely convinced that all of these lines
> of code can be removed :-)
> 
> 

-- 


Regards
Gui Jianfeng
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Gui Jianfeng
Development Dept.I
Nanjing Fujitsu Nanda Software Tech. Co., Ltd.(FNST)
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