@@ -6369,6 +6369,22 @@ nfs4_anylock_blockers(struct nfs4_client *clp)
return false;
}
+static void nfsd4_drop_conns(struct nfsd_net *nn, struct nfs4_client *clp)
+{
+ struct svc_xprt *xprt;
+
+ /* stop requeueing callback in nfsd4_run_cb_work */
+ nfsd4_kill_callback(clp);
+
+ spin_lock_bh(&nn->nfsd_serv->sv_lock);
+ list_for_each_entry(xprt, &nn->nfsd_serv->sv_tempsocks, xpt_list) {
+ if (rpc_cmp_addr((struct sockaddr *)&clp->cl_addr,
+ (struct sockaddr *)&xprt->xpt_remote))
+ svc_xprt_deferred_close(xprt);
+ }
+ spin_unlock_bh(&nn->nfsd_serv->sv_lock);
+}
+
static void
nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
struct laundry_time *lt)
@@ -6376,10 +6392,13 @@ nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
unsigned int maxreap, reapcnt = 0;
struct list_head *pos, *next;
struct nfs4_client *clp;
+ struct list_head conn_reaplist;
+ bool drop;
maxreap = (atomic_read(&nn->nfs4_client_count) >= nn->nfs4_max_clients) ?
NFSD_CLIENT_MAX_TRIM_PER_RUN : 0;
INIT_LIST_HEAD(reaplist);
+ INIT_LIST_HEAD(&conn_reaplist);
spin_lock(&nn->client_lock);
list_for_each_safe(pos, next, &nn->client_lru) {
clp = list_entry(pos, struct nfs4_client, cl_lru);
@@ -6387,16 +6406,22 @@ nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
goto exp_client;
if (!state_expired(lt, clp->cl_time))
break;
+ drop = false;
if (!atomic_read(&clp->cl_rpc_users)) {
- if (clp->cl_state == NFSD4_ACTIVE)
+ if (clp->cl_state == NFSD4_ACTIVE) {
atomic_inc(&nn->nfsd_courtesy_clients);
+ drop = true;
+ }
clp->cl_state = NFSD4_COURTESY;
}
if (!client_has_state(clp))
goto exp_client;
if (!nfs4_anylock_blockers(clp))
- if (reapcnt >= maxreap)
+ if (reapcnt >= maxreap) {
+ if (drop)
+ list_add(&clp->cl_conn_lru, &conn_reaplist);
continue;
+ }
exp_client:
if (!mark_client_expired_locked(clp)) {
list_add(&clp->cl_lru, reaplist);
@@ -6404,6 +6429,9 @@ nfs4_get_client_reaplist(struct nfsd_net *nn, struct list_head *reaplist,
}
}
spin_unlock(&nn->client_lock);
+
+ list_for_each_entry(clp, &conn_reaplist, cl_conn_lru)
+ nfsd4_drop_conns(nn, clp);
}
static void
@@ -420,6 +420,7 @@ struct nfs4_client {
int cl_cb_state;
struct nfsd4_callback cl_cb_null;
struct nfsd4_session *cl_cb_session;
+ struct list_head cl_conn_lru;
/* for all client information that callback code might need: */
spinlock_t cl_lock;
When a v4.0 client enters courtesy state all its v4 states remain valid and its fore and back channel TCP connection remained in ESTABLISHED state until the TCP keep-alive mechanism timed out and shuts down the back channel connection. The fore channel connection remains in ESTABLISHED state between 6 - 12 minutes before the NFSv4 server's 6-minute idle timer (svc_age_temp_xprts) shuts down the idle connection. Since NFSv4.1 mount uses the same TCP connection for both fore and back channel connection there is no TCP keep-alive packet sent from the server to the client. The server's idle timer does not shutdown an idle v4.1 connection since the svc_xprt->xpt_ref is more than 1: 1 for sv_tempsocks list, one for the session's nfsd4_conn and 1 for the back channel. To conserve system resources in large configuration where there are lots of idle clients, this patch drops the fore and back channel connection of NFSv4 client as soon as it enters the courtesy state. The fore and back channel connections are automatically re-established when the courtesy client reconnects. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> --- fs/nfsd/nfs4state.c | 32 ++++++++++++++++++++++++++++++-- fs/nfsd/state.h | 1 + 2 files changed, 31 insertions(+), 2 deletions(-)