2022-08-30 21:50:05

by Dai Ngo

Subject: [PATCH v4 1/2] NFSD: keep track of the number of courtesy clients in the system

Add counter nfs4_courtesy_client_count to nfsd_net to keep track
of the number of courtesy clients in the system.

Signed-off-by: Dai Ngo <[email protected]>
---
fs/nfsd/netns.h | 2 ++
fs/nfsd/nfs4state.c | 13 ++++++++++++-
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index ffe17743cc74..2695dff1378a 100644
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h
@@ -192,6 +192,8 @@ struct nfsd_net {

atomic_t nfs4_client_count;
int nfs4_max_clients;
+
+ atomic_t nfsd_courtesy_client_count;
};

/* Simple check to find out if a given net was properly initialized */
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index c5d199d7e6b4..eaf7b4dcea33 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -169,6 +169,8 @@ static __be32 get_client_locked(struct nfs4_client *clp)
if (is_client_expired(clp))
return nfserr_expired;
atomic_inc(&clp->cl_rpc_users);
+ if (clp->cl_state != NFSD4_ACTIVE)
+ atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);
clp->cl_state = NFSD4_ACTIVE;
return nfs_ok;
}
@@ -190,6 +192,8 @@ renew_client_locked(struct nfs4_client *clp)

list_move_tail(&clp->cl_lru, &nn->client_lru);
clp->cl_time = ktime_get_boottime_seconds();
+ if (clp->cl_state != NFSD4_ACTIVE)
+ atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);
clp->cl_state = NFSD4_ACTIVE;
}

@@ -2233,6 +2237,8 @@ __destroy_client(struct nfs4_client *clp)
if (clp->cl_cb_conn.cb_xprt)
svc_xprt_put(clp->cl_cb_conn.cb_xprt);
atomic_add_unless(&nn->nfs4_client_count, -1, 0);
+ if (clp->cl_state != NFSD4_ACTIVE)
+ atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);
free_client(clp);
wake_up_all(&expiry_wq);
}
@@ -4356,6 +4362,8 @@ void nfsd4_init_leases_net(struct nfsd_net *nn)
max_clients = (u64)si.totalram * si.mem_unit / (1024 * 1024 * 1024);
max_clients *= NFS4_CLIENTS_PER_GB;
nn->nfs4_max_clients = max_t(int, max_clients, NFS4_CLIENTS_PER_GB);
+
+ atomic_set(&nn->nfsd_courtesy_client_count, 0);
}

static void init_nfs4_replay(struct nfs4_replay *rp)
@@ -5878,8 +5886,11 @@ nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
goto exp_client;
if (!state_expired(lt, clp->cl_time))
break;
- if (!atomic_read(&clp->cl_rpc_users))
+ if (!atomic_read(&clp->cl_rpc_users)) {
+ if (clp->cl_state == NFSD4_ACTIVE)
+ atomic_inc(&nn->nfsd_courtesy_client_count);
clp->cl_state = NFSD4_COURTESY;
+ }
if (!client_has_state(clp))
goto exp_client;
if (!nfs4_anylock_blockers(clp))
--
2.9.5

2022-08-31 14:37:02

by Chuck Lever III

Subject: Re: [PATCH v4 1/2] NFSD: keep track of the number of courtesy clients in the system

> On Aug 30, 2022, at 5:48 PM, Dai Ngo <[email protected]> wrote:
>
> Add counter nfs4_courtesy_client_count to nfsd_net to keep track
> of the number of courtesy clients in the system.
>
> Signed-off-by: Dai Ngo <[email protected]>
> ---
> fs/nfsd/netns.h | 2 ++
> fs/nfsd/nfs4state.c | 13 ++++++++++++-
> 2 files changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
> index ffe17743cc74..2695dff1378a 100644
> --- a/fs/nfsd/netns.h
> +++ b/fs/nfsd/netns.h
> @@ -192,6 +192,8 @@ struct nfsd_net {
>
> atomic_t nfs4_client_count;
> int nfs4_max_clients;
> +
> + atomic_t nfsd_courtesy_client_count;

See comment for 2/2: rename this variable?


> };
>
> /* Simple check to find out if a given net was properly initialized */
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index c5d199d7e6b4..eaf7b4dcea33 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -169,6 +169,8 @@ static __be32 get_client_locked(struct nfs4_client *clp)
> if (is_client_expired(clp))
> return nfserr_expired;
> atomic_inc(&clp->cl_rpc_users);
> + if (clp->cl_state != NFSD4_ACTIVE)
> + atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);

This appears to be a common bit of logic. Create a helper for it?


> clp->cl_state = NFSD4_ACTIVE;
> return nfs_ok;
> }
> @@ -190,6 +192,8 @@ renew_client_locked(struct nfs4_client *clp)
>
> list_move_tail(&clp->cl_lru, &nn->client_lru);
> clp->cl_time = ktime_get_boottime_seconds();
> + if (clp->cl_state != NFSD4_ACTIVE)
> + atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);
> clp->cl_state = NFSD4_ACTIVE;
> }
>
> @@ -2233,6 +2237,8 @@ __destroy_client(struct nfs4_client *clp)
> if (clp->cl_cb_conn.cb_xprt)
> svc_xprt_put(clp->cl_cb_conn.cb_xprt);
> atomic_add_unless(&nn->nfs4_client_count, -1, 0);
> + if (clp->cl_state != NFSD4_ACTIVE)
> + atomic_add_unless(&nn->nfsd_courtesy_client_count, -1, 0);
> free_client(clp);
> wake_up_all(&expiry_wq);
> }
> @@ -4356,6 +4362,8 @@ void nfsd4_init_leases_net(struct nfsd_net *nn)
> max_clients = (u64)si.totalram * si.mem_unit / (1024 * 1024 * 1024);
> max_clients *= NFS4_CLIENTS_PER_GB;
> nn->nfs4_max_clients = max_t(int, max_clients, NFS4_CLIENTS_PER_GB);
> +
> + atomic_set(&nn->nfsd_courtesy_client_count, 0);
> }
>
> static void init_nfs4_replay(struct nfs4_replay *rp)
> @@ -5878,8 +5886,11 @@ nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
> goto exp_client;
> if (!state_expired(lt, clp->cl_time))
> break;
> - if (!atomic_read(&clp->cl_rpc_users))
> + if (!atomic_read(&clp->cl_rpc_users)) {
> + if (clp->cl_state == NFSD4_ACTIVE)
> + atomic_inc(&nn->nfsd_courtesy_client_count);
> clp->cl_state = NFSD4_COURTESY;
> + }
> if (!client_has_state(clp))
> goto exp_client;
> if (!nfs4_anylock_blockers(clp))
> --
> 2.9.5
>

--
Chuck Lever