From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [RFC] bpf: change bpf syacall to use u64 temp variables
Date: Mon, 19 Oct 2015 10:55:22 +0200
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To: yalin wang <yalin.wang2010@gmail.com>, ast@kernel.org,
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On 10/19/2015 09:10 AM, yalin wang wrote:
> This patch change map_lookup_elem() and map_update_elem() function
> to use u64 temp variable if the key_size or value_size is less than
> u64, we don't need use kmalloc() for these small variables.
>
> Signed-off-by: yalin wang <yalin.wang2010@gmail.com>

 From an application PoV that has to make the bpf(2) syscall, how
much do we actually gain from this? I'm curious, did you perform
some benchmarks that show a noticeable difference?