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Subject: Re: [RFC PATCH] mm, oom: allow oom reaper to race with exit_mmap
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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Michal Hocko wrote:
> > I wonder why you prefer timeout based approach. Your patch will after all
> > set MMF_OOM_SKIP if operations between down_write() and up_write() took
> > more than one second.
> 
> if we reach down_write then we have unmapped the address space in
> exit_mmap and oom reaper cannot do much more.

So, by the time down_write() is called, majority of memory is already released, isn't it?

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Subject: Re: [RFC PATCH] mm, oom: allow oom reaper to race with exit_mmap
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
References: <20170626130346.26314-1-mhocko@kernel.org>
	<201706271952.FEB21375.SFJFHOQLOtVOMF@I-love.SAKURA.ne.jp>
	<20170627112650.GK28072@dhcp22.suse.cz>
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Michal Hocko wrote:
> > I wonder why you prefer timeout based approach. Your patch will after all
> > set MMF_OOM_SKIP if operations between down_write() and up_write() took
> > more than one second.
> 
> if we reach down_write then we have unmapped the address space in
> exit_mmap and oom reaper cannot do much more.

So, by the time down_write() is called, majority of memory is already released, isn't it?

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