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Date: Tue, 4 Oct 2011 09:43:32 +0400
From: Glauber Costa <glommer@parallels.com>
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To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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Subject: Re: [PATCH v4 4/8] per-cgroup tcp buffers control
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On 10/04/2011 05:16 AM, KAMEZAWA Hiroyuki wrote:
> It seems memcg->tcp.tcp_memory_pressure has no locks and not atomic.
>
> no problematic race ?
>
> Thanks,
> -Kame
Well,

prior to this patch, it was a global variable. And nobody complained so 
far...

My impression is that the only thing that really needs to be atomic is
the memory accounting, which is already. If we miss a memory pressure 
condition entry, we'll get to it next time.