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 <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index ffe1774..55c7006 100644 (file)
--- 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_clients;
 };
 
 /* 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 54bc704..a248ecf 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -160,6 +160,13 @@ static bool is_client_expired(struct nfs4_client *clp)
        return clp->cl_time == 0;
 }
 
+static void nfsd4_dec_courtesy_client_count(struct nfsd_net *nn,
+                                       struct nfs4_client *clp)
+{
+       if (clp->cl_state != NFSD4_ACTIVE)
+               atomic_add_unless(&nn->nfsd_courtesy_clients, -1, 0);
+}
+
 static __be32 get_client_locked(struct nfs4_client *clp)
 {
        struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
@@ -169,6 +176,7 @@ static __be32 get_client_locked(struct nfs4_client *clp)
        if (is_client_expired(clp))
                return nfserr_expired;
        atomic_inc(&clp->cl_rpc_users);
+       nfsd4_dec_courtesy_client_count(nn, clp);
        clp->cl_state = NFSD4_ACTIVE;
        return nfs_ok;
 }
@@ -190,6 +198,7 @@ renew_client_locked(struct nfs4_client *clp)
 
        list_move_tail(&clp->cl_lru, &nn->client_lru);
        clp->cl_time = ktime_get_boottime_seconds();
+       nfsd4_dec_courtesy_client_count(nn, clp);
        clp->cl_state = NFSD4_ACTIVE;
 }
 
@@ -2235,6 +2244,7 @@ __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);
+       nfsd4_dec_courtesy_client_count(nn, clp);
        free_client(clp);
        wake_up_all(&expiry_wq);
 }
@@ -4358,6 +4368,8 @@ 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_clients, 0);
 }
 
 static void init_nfs4_replay(struct nfs4_replay *rp)
@@ -5911,8 +5923,11 @@ 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_clients);
                        clp->cl_state = NFSD4_COURTESY;
+               }
                if (!client_has_state(clp))
                        goto exp_client;
                if (!nfs4_anylock_blockers(clp))