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From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: ndo_get_stats and rtnl_netlink
Date: Mon, 10 Sep 2012 21:15:14 +0200
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Cc: Shlomo Pongartz <shlomop@mellanox.com>, netdev@vger.kernel.org
To: Or Gerlitz <or.gerlitz@gmail.com>
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On Mon, 2012-09-10 at 22:10 +0300, Or Gerlitz wrote:
> On Mon, Sep 10, 2012 at 12:09 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> 
> > RTNL locking is not needed to fetch stats, and would be overkill.
> > Each driver has its own way to protect/gather its stats.
> 
> FWIW, again, when dev_get_stats is called from rtnl_fill_ifinfo e.g as
> of invocation
> of "ip link show <interface>, there IS RTNL locking, is that a problem?
> 
> Or.

Why should it be a problem ?

A dev_get_stats() is not allowed to sleep, so its not allowed to use
RTNL by itself.

So caller might use RTNL, we dont care at all.