From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH RFC net-next 18/18] net/ipv4: Optimization for fib_info
 lookup
Date: Sat, 1 Sep 2018 13:43:34 -0700
Message-ID: <20180901134334.5fc199fb@xeon-e3>
References: <20180901004954.7145-1-dsahern@kernel.org>
        <20180901004954.7145-19-dsahern@kernel.org>
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Cc: netdev@vger.kernel.org, roopa@cumulusnetworks.com,
        sharpd@cumulusnetworks.com, idosch@mellanox.com,
        davem@davemloft.net, David Ahern <dsahern@gmail.com>
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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.