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Date: Fri, 12 Jul 2002 15:27:09 -0700
From: Andrew Morton <akpm@zip.com.au>
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To: "David S. Miller" <davem@redhat.com>
CC: alan@lxorguk.ukuu.org.uk, matts@ksu.edu, shemminger@osdl.org,
       linux-kernel@vger.kernel.org
Subject: Re: 64 bit netdev stats counter
References: <1026516053.9958.33.camel@irongate.swansea.linux.org.uk> <20020712.150607.35506145.davem@redhat.com>
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"David S. Miller" wrote:
> 
>    From: Alan Cox <alan@lxorguk.ukuu.org.uk>
>    Date: 13 Jul 2002 00:20:53 +0100
> 
>    gcc will output
> 
>                 increment low 32bit
>                 if zero
>                         increment high
> 
>    Which means we can rapidly get 2^32 out of sync
> 
> True and this equals the "fix" suggested C code involving
> two 32-bit counters that the original author posted :-)
> 

Could you make the counters per-cpu and only add them all up
in the rare case where someone wants to read the stats?

And then change all the drivers ;)

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