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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Dai Ngo <dai.ngo@oracle.com>
CC:     "jlayton@kernel.org" <jlayton@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v5 1/4] NFSD: refactoring courtesy_client_reaper to a
 generic low memory shrinker
Thread-Topic: [PATCH v5 1/4] NFSD: refactoring courtesy_client_reaper to a
 generic low memory shrinker
Thread-Index: AQHY+jb36XA2Be0450iJEIXwUAubRK5DMegA
Date:   Thu, 17 Nov 2022 14:45:00 +0000
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> On Nov 16, 2022, at 10:44 PM, Dai Ngo <dai.ngo@oracle.com> wrote:
>=20
> Refactoring courtesy_client_reaper to generic low memory
> shrinker so it can be used for other purposes.
>=20
> Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
> ---
> fs/nfsd/nfs4state.c | 25 ++++++++++++++++---------
> 1 file changed, 16 insertions(+), 9 deletions(-)
>=20
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 836bd825ca4a..142481bc96de 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -4347,7 +4347,7 @@ nfsd4_init_slabs(void)
> }
>=20
> static unsigned long
> -nfsd_courtesy_client_count(struct shrinker *shrink, struct shrink_contro=
l *sc)
> +nfsd_lowmem_shrinker_count(struct shrinker *shrink, struct shrink_contro=
l *sc)
> {
> 	int cnt;
> 	struct nfsd_net *nn =3D container_of(shrink,
> @@ -4360,7 +4360,7 @@ nfsd_courtesy_client_count(struct shrinker *shrink,=
 struct shrink_control *sc)
> }
>=20
> static unsigned long
> -nfsd_courtesy_client_scan(struct shrinker *shrink, struct shrink_control=
 *sc)
> +nfsd_lowmem_shrinker_scan(struct shrinker *shrink, struct shrink_control=
 *sc)
> {
> 	return SHRINK_STOP;
> }
> @@ -4387,8 +4387,8 @@ nfsd4_init_leases_net(struct nfsd_net *nn)
> 	nn->nfs4_max_clients =3D max_t(int, max_clients, NFS4_CLIENTS_PER_GB);
>=20
> 	atomic_set(&nn->nfsd_courtesy_clients, 0);
> -	nn->nfsd_client_shrinker.scan_objects =3D nfsd_courtesy_client_scan;
> -	nn->nfsd_client_shrinker.count_objects =3D nfsd_courtesy_client_count;
> +	nn->nfsd_client_shrinker.scan_objects =3D nfsd_lowmem_shrinker_scan;
> +	nn->nfsd_client_shrinker.count_objects =3D nfsd_lowmem_shrinker_count;
> 	nn->nfsd_client_shrinker.seeks =3D DEFAULT_SEEKS;
> 	return register_shrinker(&nn->nfsd_client_shrinker, "nfsd-client");
> }
> @@ -6125,17 +6125,24 @@ laundromat_main(struct work_struct *laundry)
> }
>=20
> static void
> -courtesy_client_reaper(struct work_struct *reaper)
> +courtesy_client_reaper(struct nfsd_net *nn)
> {
> 	struct list_head reaplist;
> -	struct delayed_work *dwork =3D to_delayed_work(reaper);
> -	struct nfsd_net *nn =3D container_of(dwork, struct nfsd_net,
> -					nfsd_shrinker_work);
>=20
> 	nfs4_get_courtesy_client_reaplist(nn, &reaplist);
> 	nfs4_process_client_reaplist(&reaplist);
> }
>=20
> +static void
> +nfsd4_lowmem_shrinker(struct work_struct *work)

All shrinkers run due to low memory, so I think this name
is a bit redundant. How about nfsd4_state_shrinker?


> +{
> +	struct delayed_work *dwork =3D to_delayed_work(work);
> +	struct nfsd_net *nn =3D container_of(dwork, struct nfsd_net,
> +				nfsd_shrinker_work);
> +
> +	courtesy_client_reaper(nn);
> +}
> +
> static inline __be32 nfs4_check_fh(struct svc_fh *fhp, struct nfs4_stid *=
stp)
> {
> 	if (!fh_match(&fhp->fh_handle, &stp->sc_file->fi_fhandle))
> @@ -7958,7 +7965,7 @@ static int nfs4_state_create_net(struct net *net)
> 	INIT_LIST_HEAD(&nn->blocked_locks_lru);
>=20
> 	INIT_DELAYED_WORK(&nn->laundromat_work, laundromat_main);
> -	INIT_DELAYED_WORK(&nn->nfsd_shrinker_work, courtesy_client_reaper);
> +	INIT_DELAYED_WORK(&nn->nfsd_shrinker_work, nfsd4_lowmem_shrinker);
> 	get_net(net);
>=20
> 	return 0;
> --=20
> 2.9.5
>=20

--
Chuck Lever