Received-SPF: pass (google.com: domain of linux-ext4-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
From:   Andreas Dilger <adilger@dilger.ca>
Mime-Version: 1.0 (1.0)
Subject: Re: [RFCv1 20/72] libext2fs: avoid too much memory allocation in case fs_num_threads
Date:   Fri, 18 Nov 2022 07:37:13 -0600
Message-Id: <A7D7B449-6BBF-4FAC-81A1-4738BD0271DD@dilger.ca>
References: <5ae4498b906ea4adffcca5546e2c9deba39dd05a.1667822611.git.ritesh.list@gmail.com>
Cc:     Theodore Ts'o <tytso@mit.edu>, linux-ext4@vger.kernel.org,
        Harshad Shirwadkar <harshadshirwadkar@gmail.com>,
        Wang Shilong <wshilong@ddn.com>,
        Andreas Dilger <adilger.kernel@dilger.ca>, Li Xi <lixi@ddn.com>
In-Reply-To: <5ae4498b906ea4adffcca5546e2c9deba39dd05a.1667822611.git.ritesh.list@gmail.com>
To:     "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Precedence: bulk

On Nov 7, 2022, at 06:24, Ritesh Harjani (IBM) <ritesh.list@gmail.com> wrote=
:
>=20
> =EF=BB=BFFrom: Wang Shilong <wshilong@ddn.com>
>=20
> e2fsck init memory according to filesystem inodes/dir numbers
> recorded in the superblock, this should be aware of filesystem
> number of threads, otherwise, oom can happen.
>=20
> So in case of fs->fs_num_threads, this patch controls the amount of
> memory consumed for running multiple threads in e2fsck.
>=20
> Signed-off-by: Wang Shilong <wshilong@ddn.com>
> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>

Reviewed-by: Andreas Dilger <adilger@dilger.ca>

> ---
> lib/ext2fs/dblist.c | 2 ++
> lib/ext2fs/icount.c | 4 ++++
> 2 files changed, 6 insertions(+)
>=20
> diff --git a/lib/ext2fs/dblist.c b/lib/ext2fs/dblist.c
> index 5568b8ec..c19e17bc 100644
> --- a/lib/ext2fs/dblist.c
> +++ b/lib/ext2fs/dblist.c
> @@ -58,6 +58,8 @@ static errcode_t make_dblist(ext2_filsys fs, ext2_ino_t s=
ize,
>        if (retval)
>            goto cleanup;
>        dblist->size =3D (num_dirs * 2) + 12;
> +        if (fs->fs_num_threads)
> +            dblist->size /=3D fs->fs_num_threads;
>    }
>    len =3D (size_t) sizeof(struct ext2_db_entry2) * dblist->size;
>    dblist->count =3D count;
> diff --git a/lib/ext2fs/icount.c b/lib/ext2fs/icount.c
> index 766eccca..48665c7e 100644
> --- a/lib/ext2fs/icount.c
> +++ b/lib/ext2fs/icount.c
> @@ -237,6 +237,8 @@ errcode_t ext2fs_create_icount_tdb(ext2_filsys fs EXT2=
FS_NO_TDB_UNUSED,
>     * value.
>     */
>    num_inodes =3D fs->super->s_inodes_count - fs->super->s_free_inodes_cou=
nt;
> +    if (fs->fs_num_threads)
> +        num_inodes /=3D fs->fs_num_threads;
>=20
>    icount->tdb =3D tdb_open(fn, num_inodes, TDB_NOLOCK | TDB_NOSYNC,
>                   O_RDWR | O_CREAT | O_TRUNC, 0600);
> @@ -288,6 +290,8 @@ errcode_t ext2fs_create_icount2(ext2_filsys fs, int fl=
ags, unsigned int size,
>        if (retval)
>            goto errout;
>        icount->size +=3D fs->super->s_inodes_count / 50;
> +        if (fs->fs_num_threads)
> +            icount->size /=3D fs->fs_num_threads;
>    }
>=20
>    bytes =3D (size_t) (icount->size * sizeof(struct ext2_icount_el));
> --=20
> 2.37.3
>=20