From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [PATCH 00/16] Remove the ipv4 routing cache
Date: Fri, 27 Jul 2012 07:53:07 -0700
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Cc: David Miller <davem@davemloft.net>, alexander.duyck@gmail.com,
	netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet <eric.dumazet@gmail.com> writes:

> Now IP route cache is removed, we should make sure fib structures
> cant share cache lines with possibly often dirtied objects.
>
> On x86, kmalloc-96 cache can be source of such problems.
>
> Signed-off-by: Eric Dumazet <edumazet@google.com>


> +static inline void *fib_zalloc(size_t size)
> +{
> +	/* We want to avoid possible false sharing */
> +	return kzalloc(max_t(size_t, 128, size), GFP_KERNEL);

Why the hard coded 128 here?

It seems more portable and obvious to do 
	return kzalloc(round_up(size, L1_CACHE_BYTES), GFP_KERNEL);

> +}

Eric