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Date: Fri, 22 Jun 2018 15:10:13 +0200
From: Michal Hocko <mhocko@kernel.org>
Subject: Re: dm bufio: Reduce dm_bufio_lock contention
Message-ID: <20180622131013.GA10465@dhcp22.suse.cz>
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To: Mikulas Patocka <mpatocka@redhat.com>
Cc: jing xia <jing.xia.mail@gmail.com>, Mike Snitzer <snitzer@redhat.com>, agk@redhat.com, dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org

On Fri 22-06-18 08:44:52, Mikulas Patocka wrote:
> On Fri, 22 Jun 2018, Michal Hocko wrote:
[...]
> > Why? How are you going to audit all the callers that the behavior makes
> > sense and moreover how are you going to ensure that future usage will
> > still make sense. The more subtle side effects gfp flags have the harder
> > they are to maintain.
> 
> I did audit them - see the previous email in this thread: 
> https://www.redhat.com/archives/dm-devel/2018-June/thread.html

I do not see any mention about throttling expectations for those users.
You have focused only on the allocation failure fallback AFAIR
-- 
Michal Hocko
SUSE Labs