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From: John Baldwin <jhb@freebsd.org>
To: freebsd-hackers@freebsd.org
Date: Tue, 21 Aug 2012 09:43:08 -0400
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	(bigwig.baldwin.cx); Tue, 21 Aug 2012 10:52:56 -0400 (EDT)
Cc: freebsd-net@freebsd.org, Mitya <mitya@cabletv.dp.ua>
Subject: Re: Replace bcopy() to update ether_addr
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On Monday, August 20, 2012 10:46:12 am Mitya wrote:
> Hi.
> I found some overhead code in /src/sys/net/if_ethersubr.c and 
> /src/sys/netgraph/ng_ether.c
> 
> It contains strings, like bcopy(src, dst, ETHER_ADDR_LEN);
> When src and dst are "struct ether_addr*", and ETHER_ADDR_LEN equal 6.
> This code call every time, when we send Ethernet packet.
> On example, on my machine in invoked nearly 20K per second.
> 
> Why we are use bcopy(), to copy only 6 bytes?
> Answer - in some architectures we are can not directly copy unaligned data.
> 
> I propose this solution.
> 
> In file /usr/src/include/net/ethernet.h add this lines:
> 
> static inline void ether_addr_copy(ether_addr* src, ether_addr* dst) {
> #if defined(__i386__) || defined(__amd64__)
>      *dst = *src;
> #else
>      bcopy(src, dst, ETHER_ADDR_LEN);
> #endif
> }

Doesn't '*dst = *src' just work on all platforms?

-- 
John Baldwin