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Date: Mon, 28 Jan 2019 06:54:07 -0800
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH 2/2] mm: Consider subtrees in memory.events
Message-ID: <20190128145407.GP50184@devbig004.ftw2.facebook.com>
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To: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>, Chris Down <chris@chrisdown.name>, Andrew Morton <akpm@linux-foundation.org>, Roman Gushchin <guro@fb.com>, Dennis Zhou <dennis@kernel.org>, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kernel-team@fb.com

Hello,

On Mon, Jan 28, 2019 at 03:52:10PM +0100, Michal Hocko wrote:
> > All .events files generate aggregated stateful notifications.  For
> > anyone to do anything, they'd have to remember the previous state to
> > identify what actually happened.  Being hierarchical, it'd of course
> > need to walk down when an event triggers.
> 
> And how do you do that in a raceless fashion?

Hmm... I'm having trouble imagining why this would be a problem.  How
would it race?

Thanks.

-- 
tejun