From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [PATCH] fib_trie: rescan if key is lost during dump
Date: Fri, 25 Jan 2008 09:23:00 +0100
Message-ID: <20080125082300.GA2257@ff.dom.local>
References: <20080124135112.32b5c1c7@deepthought>
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Cc: David Miller <davem@davemloft.net>, kaber@trash.net,
	netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@linux-foundation.org>
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On 24-01-2008 22:51, Stephen Hemminger wrote:
> Normally during a dump the key of the last dumped entry is used for
> continuation, but since lock is dropped it might be lost. In that case
> fallback to the old counter based N^2 behaviour.  This means the dump will end up
> skipping some routes which matches what FIB_HASH does.
> 
> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
...
> @@ -1918,35 +1931,37 @@ static int fn_trie_dump(struct fib_table
>  	struct leaf *l;
>  	struct trie *t = (struct trie *) tb->tb_data;
>  	t_key key = cb->args[2];
> +	int count = cb->args[3];
>  
>  	rcu_read_lock();

Sorry, but I lost the point: is rtnl held or not held here at the moment?
If held, how this rcu_read_lock can help? Maybe some additional comment
in the code?

Thanks,
Jarek P.