From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: 64-bit net_device_stats
Date: Wed, 2 Jun 2010 14:59:12 -0700
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Cc: David Miller <davem@davemloft.net>, junchangwang@gmail.com,
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On Wed, 02 Jun 2010 22:34:29 +0100
Ben Hutchings <bhutchings@solarflare.com> wrote:

> Changing the counter types to u64 for 32-bit architectures would remove
> atomicity and expose half-updated counters to userland.  Changing the
> driver interface significantly so that atomicity is not needed would
> require changes to hundreds of drivers.

Another big issue is maintaining ABI compatibility for /proc and ioctl
interfaces. So bigger values would only be available through netlink,
and most applications using counters don't use netlink. 

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