NFS: Lock the slot table from a single place during setup sequence
authorAnna Schumaker <Anna.Schumaker@Netapp.com>
Tue, 10 Jan 2017 21:13:27 +0000 (16:13 -0500)
committerAnna Schumaker <Anna.Schumaker@Netapp.com>
Mon, 30 Jan 2017 18:14:50 +0000 (13:14 -0500)
Rather than implementing this twice for NFS v4.0 and v4.1

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
fs/nfs/nfs4proc.c

index dcb2f73c7d4c9a4d6c76c7b5ae5b27f0be63e109..681cb5e77da2ee600357b7227418d22a0833cef4 100644 (file)
@@ -629,7 +629,6 @@ static int nfs40_setup_sequence(struct nfs4_slot_table *tbl,
 {
        struct nfs4_slot *slot;
 
-       spin_lock(&tbl->slot_tbl_lock);
        if (nfs4_slot_tbl_draining(tbl) && !args->sa_privileged)
                goto out_sleep;
 
@@ -639,13 +638,10 @@ static int nfs40_setup_sequence(struct nfs4_slot_table *tbl,
                        task->tk_timeout = HZ >> 2;
                goto out_sleep;
        }
-       spin_unlock(&tbl->slot_tbl_lock);
 
        slot->privileged = args->sa_privileged ? 1 : 0;
        args->sa_slot = slot;
        res->sr_slot = slot;
-
-       rpc_call_start(task);
        return 0;
 
 out_sleep:
@@ -654,7 +650,6 @@ out_sleep:
                                NULL, RPC_PRIORITY_PRIVILEGED);
        else
                rpc_sleep_on(&tbl->slot_tbl_waitq, task, NULL);
-       spin_unlock(&tbl->slot_tbl_lock);
        return -EAGAIN;
 }
 
@@ -889,7 +884,6 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
 
        task->tk_timeout = 0;
 
-       spin_lock(&tbl->slot_tbl_lock);
        if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state) &&
            !args->sa_privileged) {
                /* The state manager will wait until the slot table is empty */
@@ -905,7 +899,6 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
                dprintk("<-- %s: no free slots\n", __func__);
                goto out_sleep;
        }
-       spin_unlock(&tbl->slot_tbl_lock);
 
        slot->privileged = args->sa_privileged ? 1 : 0;
        args->sa_slot = slot;
@@ -922,7 +915,6 @@ static int nfs41_setup_sequence(struct nfs4_session *session,
         */
        res->sr_status = 1;
        trace_nfs4_setup_sequence(session, args);
-       rpc_call_start(task);
        return 0;
 out_sleep:
        /* Privileged tasks are queued with top priority */
@@ -931,7 +923,6 @@ out_sleep:
                                NULL, RPC_PRIORITY_PRIVILEGED);
        else
                rpc_sleep_on(&tbl->slot_tbl_waitq, task, NULL);
-       spin_unlock(&tbl->slot_tbl_lock);
        return -EAGAIN;
 }
 
@@ -984,19 +975,27 @@ int nfs4_setup_sequence(const struct nfs_client *client,
                        struct nfs4_sequence_res *res,
                        struct rpc_task *task)
 {
-#if defined(CONFIG_NFS_V4_1)
        struct nfs4_session *session = nfs4_get_session(client);
-#endif /* CONFIG_NFS_V4_1 */
+       struct nfs4_slot_table *tbl  = session ? &session->fc_slot_table :
+                                                 client->cl_slot_tbl;
+       int ret;
 
        /* slot already allocated? */
        if (res->sr_slot != NULL)
                goto out_start;
 
+       spin_lock(&tbl->slot_tbl_lock);
+
 #if defined(CONFIG_NFS_V4_1)
        if (session)
-               return nfs41_setup_sequence(session, args, res, task);
+               ret = nfs41_setup_sequence(session, args, res, task);
+       else
 #endif /* CONFIG_NFS_V4_1 */
-       return nfs40_setup_sequence(client->cl_slot_tbl, args, res, task);
+               ret = nfs40_setup_sequence(client->cl_slot_tbl, args, res, task);
+
+       spin_unlock(&tbl->slot_tbl_lock);
+       if (ret < 0)
+               return ret;
 
 out_start:
        rpc_call_start(task);