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Message-ID: <1520356831.109662.25.camel@gmail.com>
Subject: Re: [PATCH RESEND net-next] net: Do synchronize_rcu() in
 ip6mr_sk_done() only if this is needed
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Kirill Tkhai <ktkhai@virtuozzo.com>, davem@davemloft.net,
        yoshfuji@linux-ipv6.org, netdev@vger.kernel.org
Cc: Yuval Mintz <yuvalm@mellanox.com>
Date: Tue, 06 Mar 2018 09:20:31 -0800
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On Tue, 2018-03-06 at 08:58 -0800, Eric Dumazet wrote:
> 
> To be clear, your patch is fine Kirill,
> 
> I am only sad seeing one can add a synchronize_rcu() in hot path
> without anyone complaining during code review.

lpaa2:~# time for i in {1..1000}; do unshare -n /bin/false;done

real	7m18.911s
user	0m0.185s
sys	0m2.314s

Instead of less than 10 seconds not a long time ago :/