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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Dongliang Mu <dzm91@hust.edu.cn>
CC:     Dongliang Mu <mudongliangabcd@gmail.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] nfsd: make destory function more elegant
Thread-Topic: [PATCH] nfsd: make destory function more elegant
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Date:   Thu, 2 Jun 2022 14:30:00 +0000
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> On Jun 2, 2022, at 1:56 AM, Dongliang Mu <dzm91@hust.edu.cn> wrote:
>=20
> From: Dongliang Mu <mudongliangabcd@gmail.com>
>=20
> In init_nfsd, the undo operation of create_proc_exports_entry is:
>=20
>        remove_proc_entry("fs/nfs/exports", NULL);
>        remove_proc_entry("fs/nfs", NULL);
>=20
> This may lead to maintaince issue. Declare the undo function

"maintenance"


> destroy_proc_exports_entry based on CONFIG_PROC_FS

IIUC, the issue is that if CONFIG_PROC_FS is not set,
fs/nfsd/nfsctl.c fails to compile?


> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
> fs/nfsd/nfsctl.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>=20
> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
> index 0621c2faf242..83b34ccbef5a 100644
> --- a/fs/nfsd/nfsctl.c
> +++ b/fs/nfsd/nfsctl.c
> @@ -1450,11 +1450,21 @@ static int create_proc_exports_entry(void)
> 	}
> 	return 0;
> }
> +
> +static void destroy_proc_exports_entry(void)
> +{
> +	remove_proc_entry("fs/nfs/exports", NULL);
> +	remove_proc_entry("fs/nfs", NULL);
> +}
> #else /* CONFIG_PROC_FS */
> static int create_proc_exports_entry(void)
> {
> 	return 0;
> }
> +
> +static void destroy_proc_exports_entry(void)
> +{
> +}
> #endif
>=20
> unsigned int nfsd_net_id;
> @@ -1555,8 +1565,7 @@ static int __init init_nfsd(void)
> out_free_subsys:
> 	unregister_pernet_subsys(&nfsd_net_ops);
> out_free_exports:
> -	remove_proc_entry("fs/nfs/exports", NULL);
> -	remove_proc_entry("fs/nfs", NULL);
> +	destroy_proc_exports_entry();
> out_free_lockd:
> 	nfsd_lockd_shutdown();
> 	nfsd_drc_slab_free();
> @@ -1576,8 +1585,7 @@ static void __exit exit_nfsd(void)
> 	unregister_cld_notifier();
> 	unregister_pernet_subsys(&nfsd_net_ops);
> 	nfsd_drc_slab_free();
> -	remove_proc_entry("fs/nfs/exports", NULL);
> -	remove_proc_entry("fs/nfs", NULL);
> +	destroy_proc_exports_entry();
> 	nfsd_stat_shutdown();
> 	nfsd_lockd_shutdown();
> 	nfsd4_free_slabs();
> --=20
> 2.25.1
>=20

--
Chuck Lever