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From: Lance Yang <ioworker0@gmail.com>
Date: Mon, 3 Jun 2024 12:13:25 +0800
Message-ID: <CAK1f24mj_LFEU8mP=vGhJMWLAq1JANWqtipPwMLvYh6nrp65Dg@mail.gmail.com>
Subject: Re: [PATCH 1/1] mm/mlock: implement folio_mlock_step() using folio_pte_batch()
To: Matthew Wilcox <willy@infradead.org>
Cc: akpm@linux-foundation.org, ryan.roberts@arm.com, david@redhat.com, 
	21cnbao@gmail.com, baolin.wang@linux.alibaba.com, ziy@nvidia.com, 
	fengwei.yin@intel.com, ying.huang@intel.com, libang.li@antgroup.com, 
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
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Hi Matthew,

Thanks for taking time to review!

On Mon, Jun 3, 2024 at 11:36=E2=80=AFAM Matthew Wilcox <willy@infradead.org=
> wrote:
>
> On Mon, Jun 03, 2024 at 11:31:17AM +0800, Lance Yang wrote:
> >  {
> > -     unsigned int count, i, nr =3D folio_nr_pages(folio);
> > -     unsigned long pfn =3D folio_pfn(folio);
> > -     pte_t ptent =3D ptep_get(pte);
>
> Please don't move type declarations later in the function.  Just because
> you can doesn't mean you should.

Thanks for pointing this out, I'll adjust as you suggested.

>
> > -     if (!folio_test_large(folio))
> > +     if (likely(!folio_test_large(folio)))
> >               return 1;
>
> How likely is this now?  How likely will it be in two years time?
> Does this actually make any difference in either code generation or
> performance?

IMO, this hint could impact code generation and performance :)
But it seems that 'likely' is not necessary here. I'll remove it.

Thanks again for your time!
Lance

>