[PATCH Version 3 4/4] NFSv4.1: do not drain session on CB_RECALL_SLOT

[andros@netapp.com]

From: Andy Adamson <andros@netapp.com>

Dynamic slots allow for reducing the number of active slots without
the need to drain the session.

Signed-off-by: Andy Adamson <andros@netapp.com>
---
 fs/nfs/callback_proc.c |    6 +++++-
 fs/nfs/nfs4_fs.h       |    1 -
 fs/nfs/nfs4state.c     |   36 ------------------------------------
 3 files changed, 5 insertions(+), 38 deletions(-)

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 8039a41..4e4ee2a 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -578,8 +578,12 @@ __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
 	if (args->crsa_target_max_slots == fc_tbl->max_slots)
 		goto out;
 
+        spin_lock(&fc_tbl->slot_tbl_lock);
 	fc_tbl->target_max_slots = args->crsa_target_max_slots;
-	nfs41_handle_recall_slot(cps->clp);
+        fc_tbl->max_slots = fc_tbl->target_max_slots;
+        nfs4_reduce_slots_locked(fc_tbl);
+        cps->clp->cl_session->fc_attrs.max_reqs = fc_tbl->max_slots;
+        spin_unlock(&fc_tbl->slot_tbl_lock);
 out:
 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 	return status;
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index ff87169..a1f889a 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -22,7 +22,6 @@ enum nfs4_client_state {
 	NFS4CLNT_DELEGRETURN,
 	NFS4CLNT_LAYOUTRECALL,
 	NFS4CLNT_SESSION_RESET,
-	NFS4CLNT_RECALL_SLOT,
 	NFS4CLNT_LEASE_CONFIRM,
 	NFS4CLNT_SERVER_SCOPE_MISMATCH,
 };
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 8260865..c08fb3b 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1479,12 +1479,6 @@ void nfs4_schedule_session_recovery(struct nfs4_session *session)
 }
 EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
 
-void nfs41_handle_recall_slot(struct nfs_client *clp)
-{
-	set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
-	nfs4_schedule_state_manager(clp);
-}
-
 static void nfs4_reset_all_state(struct nfs_client *clp)
 {
 	if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
@@ -1559,8 +1553,6 @@ static int nfs4_reset_session(struct nfs_client *clp)
 		goto out;
 	}
 	clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
-	/* create_session negotiated new slot table */
-	clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
 
 	 /* Let the state manager reestablish state */
 	if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
@@ -1569,28 +1561,9 @@ out:
 	return status;
 }
 
-static int nfs4_recall_slot(struct nfs_client *clp)
-{
-	struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
-	struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
-
-	nfs4_begin_drain_session(clp);
-
-	spin_lock(&fc_tbl->slot_tbl_lock);
-	fc_tbl->max_slots = fc_tbl->target_max_slots;
-	nfs4_reduce_slots_locked(fc_tbl);
-	fc_tbl->target_max_slots = 0;
-	fc_attrs->max_reqs = fc_tbl->max_slots;
-	spin_unlock(&fc_tbl->slot_tbl_lock);
-
-	nfs4_end_drain_session(clp);
-	return 0;
-}
-
 #else /* CONFIG_NFS_V4_1 */
 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
 static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
-static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
 #endif /* CONFIG_NFS_V4_1 */
 
 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
@@ -1699,15 +1672,6 @@ static void nfs4_state_manager(struct nfs_client *clp)
 			nfs_client_return_marked_delegations(clp);
 			continue;
 		}
-		/* Recall session slots */
-		if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
-		   && nfs4_has_session(clp)) {
-			status = nfs4_recall_slot(clp);
-			if (status < 0)
-				goto out_error;
-			continue;
-		}
-
 
 		nfs4_clear_state_manager_bit(clp);
 		/* Did we race with an attempt to give us more work? */
-- 
1.7.6.4