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Subject: Re: [PATCH net-next] net: dsa: User per-cpu 64-bit statistics
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Florian Fainelli <f.fainelli@gmail.com>
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Date: Tue, 22 Aug 2017 05:56:51 -0700
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On Mon, 2017-08-21 at 17:10 -0700, Florian Fainelli wrote:

> Well if we return 1 from atomic_inc_return() and the previous value was
> zero, of course we are going to be bugging here. The idea behind the
> patch I suppose is to make sure that we always get an odd number upon
> u64_stats_update_begin()/entry, and an even number upon
> u64_stats_update_end()/exit, right?

Yes, this is right.