Subject: Re: [PATCH 3/3] net: core: add IFLA_STATS64 support

From: Stephen Hemminger <[email-masked]>
Date: Thu, 11 Mar 2010 14:04:06 -0800

On Thu, 11 Mar 2010 12:26:39 -0800 (PST)
David Miller <[email-masked]> wrote:

> From: Stephen Hemminger <[email-masked]>
> Date: Thu, 11 Mar 2010 12:12:39 -0800
> 
> > On Thu, 11 Mar 2010 20:57:29 +0100
> > Jan Engelhardt <[email-masked]> wrote:
> > 
> >> `ip -s link` shows interface counters truncated to 32 bit. This is
> >> because interface statistics are transported only in 32-bit quantity
> >> to userspace. This commit adds a new IFLA_STATS64 attribute that
> >> exports them in full 64 bit.
> >> 
> >> References: http://lkml.indiana.edu/hypermail/linux/kernel/0307.3/0215.html
> >> Signed-off-by: Jan Engelhardt <[email-masked]>
> >> 
> > 
> > What is the point since net_device_stats has only 32 bit counters.
> > The last time this came up the issue was is that is not possible
> > to atomically increment a 64 bit counter on most 32 bit platforms.
> 
> On 64-bit it has 64-bit counters, yet we only report 32-bit
> counters to userspace via netlink even in that case.

That make sense, but maybe we shouldn't send IFLA_STATS64 on
32bit platforms.