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Date:   Sun, 29 May 2022 10:58:18 +0800
From:   Muchun Song <songmuchun@bytedance.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     bh1scw@gmail.com, Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Roman Gushchin <roman.gushchin@linux.dev>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/slub: replace alloc_pages with folio_alloc
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On Sat, May 28, 2022 at 05:27:11PM +0100, Matthew Wilcox wrote:
> On Sun, May 29, 2022 at 12:11:58AM +0800, bh1scw@gmail.com wrote:
> > From: Fanjun Kong <bh1scw@gmail.com>
> > 
> > This patch will use folio allocation functions for allocating pages.
> 
> That's not actually a good idea.  folio_alloc() will do the
> prep_transhuge_page() step which isn't needed for slab.
>

You mean folio_alloc() is dedicated for THP allocation?  It is a little
surprise to me.  I thought folio_alloc() is just a variant of alloc_page(),
which returns a folio struct instead of a page.  Seems like I was wrong.
May I ask what made us decide to do this?

Thanks.