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Date:   Tue, 8 Jan 2019 09:20:32 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Qian Cai <cai@lca.pw>
Cc:     akpm@linux-foundation.org, Pavel.Tatashin@microsoft.com,
        mingo@kernel.org, mgorman@techsingularity.net,
        iamjoonsoo.kim@lge.com, tglx@linutronix.de, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] mm/page_owner: fix for deferred struct page init
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On Mon 07-01-19 20:53:08, Qian Cai wrote:
> 
> 
> On 1/7/19 1:43 PM, Michal Hocko wrote:
> > On Fri 04-01-19 15:18:08, Qian Cai wrote:
> > [...]
> >> Though, I can't see any really benefit of this approach apart from "beautify"
> > 
> > This is not about beautifying! This is about making the code long term
> > maintainable. As you can see it is just too easy to break it with the
> > current scheme. And that is bad especially when the code is broken
> > because of an optimization.
> > 
> 
> Understood, but the code is now fixed. If there is something fundamentally
> broken in the future, it may be a good time then to create a looks like
> hundred-line cleanup patch for long-term maintenance at the same time to fix
> real bugs.

Yeah, so revert = fix and redisign the thing to make the code more
robust longterm + allow to catch more allocation. I really fail to see
why this has to be repeated several times in this thread. Really.

-- 
Michal Hocko
SUSE Labs