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From:   JunChao Sun <sunjunchao2870@gmail.com>
Date:   Thu, 10 Nov 2022 11:44:08 +0800
Message-ID: <CAHB1NagDSOcpf8kS-K--FDUySrikT6GaFKBneFkSx-D8uyhAgA@mail.gmail.com>
Subject: Re: [PATCH] ext4: replace kmem_cache_create with KMEM_CACHE
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-ext4@vger.kernel.org, tytso@mit.edu,
        adilger.kernel@dilger.ca, jack@suse.cz
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Eric Biggers <ebiggers@kernel.org> =E4=BA=8E2022=E5=B9=B411=E6=9C=8810=E6=
=97=A5=E5=91=A8=E5=9B=9B 10:47=E5=86=99=E9=81=93=EF=BC=9A
>
> On Thu, Nov 10, 2022 at 08:53:26AM +0800, JunChao Sun wrote:
> > Yeah, maybe we should remove the SLAB_RECLAIM_ACCOUNT flag for static
> > slab, and 16828088f9e51815 ("ext4: use KMEM_CACHE instead of
> > kmem_cache_create") have done so. But should we remove
> > SLAB_RECLAIM_ACCOUNT in this patch or belong to a separate patch?
>
>
> > I'd just keep the slab flags the same in this patch.  If any flags do n=
eed to be
> > changed, that should be a separate patch.
> >
> > I think SLAB_RECLAIM_ACCOUNT is meant for for things that are directly
> > reclaimable, such as struct ext4_inode_info.  Inodes are evictable, and=
 when
> > that happens, the corresponding struct ext4_inode_info gets freed.
> >
> > bio_post_read_ctx_cache probably should use SLAB_TEMPORARY instead, sin=
ce it is
> > only used for temporary structures during I/O.
> >
> > That being said, SLAB_TEMPORARY is currently #define'd to SLAB_RECLAIM_=
ACCOUNT,
> > so currently it makes no difference in practice...

Thanks for clarifying. I will send a separate patch to remove
SLAB_RECLAIM_ACCOUNT.

>
> - Eric