From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH RFC net-next 18/18] net/ipv4: Optimization for fib_info
 lookup
Date: Tue, 4 Sep 2018 09:27:17 -0600
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References: <20180901004954.7145-1-dsahern@kernel.org>
 <20180901004954.7145-19-dsahern@kernel.org> <20180901134334.5fc199fb@xeon-e3>
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To: Stephen Hemminger <stephen@networkplumber.org>, dsahern@kernel.org
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On 9/1/18 2:43 PM, Stephen Hemminger wrote:
> On Fri, 31 Aug 2018 17:49:53 -0700
> dsahern@kernel.org wrote:
> 
>> +static inline unsigned int fib_info_hashfn_cfg(const struct fib_config *cfg)
>> +{
>> +	unsigned int mask = (fib_info_hash_size - 1);
>> +	unsigned int val = 0;
>> +
>> +	val ^= (cfg->fc_protocol << 8) | cfg->fc_scope;
> 
> Why do assignment to 0 than do initial xor?
> Why not instead just do assignment in the first statement which would be clearer.
> 

Side effect of copy-paste-adjust of the original. Will fix for the next
rfc (really need to not have 2 versions of the hashfn; need to think
through it).