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From:   Vitaly Wool <vitaly.wool@konsulko.com>
Date:   Mon, 27 Mar 2023 08:19:56 +0200
Message-ID: <CAM4kBBKdz4oSXpACw=ntwSUi4yH7H65Bu4T+5-NSFtqmUp6SoQ@mail.gmail.com>
Subject: Re: [PATCH -next v6 2/2] mm/zswap: delay the initializaton of zswap
To:     Christoph Hellwig <hch@lst.de>
Cc:     Liu Shixin <liushixin2@huawei.com>,
        Seth Jennings <sjenning@redhat.com>,
        Dan Streetman <ddstreet@ieee.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nathan Chancellor <nathan@kernel.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
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On Thu, Mar 23, 2023 at 8:59=E2=80=AFAM Christoph Hellwig <hch@lst.de> wrot=
e:
>
> On Wed, Mar 22, 2023 at 06:17:12PM +0100, Vitaly Wool wrote:
> > On Wed, Mar 22, 2023 at 10:30=E2=80=AFAM Liu Shixin <liushixin2@huawei.=
com> wrote:
> > >
> > > Since some users may not use zswap, the zswap_pool is wasted. Save me=
mory
> > > by delaying the initialization of zswap until enabled.
> >
> > To be honest, I'm not a huge fan of this. Would enabling zswap module
> > build instead solve your problem?
>
> making zswap build modular would be a mess.  It is core MM infrastructure
> and now we'd need to start dealing with adding and removing it at
> runtime as well as module refcounting.

Since when is it a core MM infrastructure? It is basically just a
frontswap frontend.

~Vitaly