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 <20240325235018.2028408-4-yosryahmed@google.com> <88957a87-fe4c-448c-a22a-9052d65ab643@linux.dev>
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From: Yosry Ahmed <yosryahmed@google.com>
Date: Wed, 27 Mar 2024 15:30:41 -0700
Message-ID: <CAJD7tkbW3+4MLkkgNK=reVCZb0JY=6o7+LC_2W-gQfYdOx1PWw@mail.gmail.com>
Subject: Re: [RFC PATCH 3/9] mm: zswap: refactor limit checking from zswap_store()
To: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Andrew Morton <akpm@linux-foundation.org>, Johannes Weiner <hannes@cmpxchg.org>, 
	Nhat Pham <nphamcs@gmail.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org
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On Tue, Mar 26, 2024 at 7:42=E2=80=AFPM Chengming Zhou <chengming.zhou@linu=
x.dev> wrote:
>
> On 2024/3/26 07:50, Yosry Ahmed wrote:
> > Refactor limit and acceptance threshold checking outside of
> > zswap_store(). This code will be moved around in a following patch, so
> > it would be cleaner to move a function call around.
> >
> > Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
> > ---
> >  mm/zswap.c | 32 ++++++++++++++++----------------
> >  1 file changed, 16 insertions(+), 16 deletions(-)
> >
> > diff --git a/mm/zswap.c b/mm/zswap.c
> > index ff1975afb7e3d..6b890c8590ef7 100644
> > --- a/mm/zswap.c
> > +++ b/mm/zswap.c
> > @@ -1415,6 +1415,21 @@ static void zswap_fill_page(void *ptr, unsigned =
long value)
> >       memset_l(page, value, PAGE_SIZE / sizeof(unsigned long));
> >  }
> >
> > +static bool zswap_check_limit(void)
> > +{
> > +     unsigned long cur_pages =3D zswap_total_pages();
> > +     unsigned long thr =3D zswap_accept_thr_pages();
> > +     unsigned long max_pages =3D zswap_max_pages();
> > +
> > +     if (cur_pages >=3D max_pages) {
> > +             zswap_pool_limit_hit++;
> > +             zswap_pool_reached_full =3D true;
> > +     } else if (zswap_pool_reached_full && cur_pages <=3D thr) {
> > +             zswap_pool_reached_full =3D false;
> > +     }
> > +     return !zswap_pool_reached_full;
>
> nit: Then we use "!zswap_check_limit()" below, double negation looks comp=
lex,
> should we change to zswap_should_reject() or something?

Good point. Will rename it in the next version.

Thanks!