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Date:   Fri, 2 Dec 2022 11:27:23 -0800 (PST)
From:   Hugh Dickins <hughd@google.com>
To:     David Rientjes <rientjes@google.com>
cc:     Matthew Wilcox <willy@infradead.org>, ye.xingchen@zte.com.cn,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/huge_memory: add TRANSPARENT_HUGEPAGE_NEVER for THP
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References: <202211301651462590168@zte.com.cn> <Y4kN9UAte0OQ6sGi@casper.infradead.org> <4a78abbc-4c07-2208-1072-af6d342c3f1a@google.com>
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On Fri, 2 Dec 2022, David Rientjes wrote:
> On Thu, 1 Dec 2022, Matthew Wilcox wrote:
> > On Wed, Nov 30, 2022 at 04:51:46PM +0800, ye.xingchen@zte.com.cn wrote:
> > > From: ye xingchen <ye.xingchen@zte.com.cn>
> > > 
> > > Sometimes we may need the /sys/kernel/mm/transparent_hugepage/enabled to
> > > default as [never] at the first time.
> > 
> > What is going wrong with THP enabled that you need to disable it?
> > 
> 
> That would be useful to know in addition to why this needs to be part of 
> .config and not simply using the kernel command line option.

There is also the puzzle of what new feature gets added by

#ifdef CONFIG_TRANSPARENT_HUGEPAGE_NEVER
#endif

Hugh