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Date: Fri, 23 Feb 2018 12:43:30 -0500 (EST)
Message-Id: <20180223.124330.1637118557891234954.davem@davemloft.net>
To: eric.dumazet@gmail.com
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Subject: Re: [PATCH v2 net] net_sched: gen_estimator: fix broken estimators
 based on percpu stats
From: David Miller <davem@davemloft.net>
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 22 Feb 2018 19:45:27 -0800

> From: Eric Dumazet <edumazet@google.com>
> 
> pfifo_fast got percpu stats lately, uncovering a bug I introduced last
> year in linux-4.10.
> 
> I missed the fact that we have to clear our temporary storage
> before calling __gnet_stats_copy_basic() in the case of percpu stats.
> 
> Without this fix, rate estimators (tc qd replace dev xxx root est 1sec
> 4sec pfifo_fast) are utterly broken.
> 
> Fixes: 1c0d32fde5bd ("net_sched: gen_estimator: complete rewrite of rate estimators")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
> v2: Perform the zeroing in est_fetch_counters() instead of caller(s)

Applied and queued up for -stable.