netdev - Re: [PATCH net-next] x86: bpf_jit: small optimization in emit_bpf_tail

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Date:   Thu, 31 Aug 2017 11:58:14 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     eric.dumazet@...il.com
Cc:     netdev@...r.kernel.org, ast@...nel.org, daniel@...earbox.net
Subject: Re: [PATCH net-next] x86: bpf_jit: small optimization in
 emit_bpf_tail_call()

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Thu, 31 Aug 2017 04:53:42 -0700

> From: Eric Dumazet <edumazet@...gle.com>
> 
> Saves 4 bytes replacing following instructions :
> 
> lea rax, [rsi + rdx * 8 + offsetof(...)] 
> mov rax, qword ptr [rax]
> cmp rax, 0
> 
> by :
> 
> mov rax, [rsi + rdx * 8 + offsetof(...)] 
> test rax, rax
> 
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>

Applied.