SUNRPC: Remove rpc_clnt->cl_count

The kref now does most of what cl_count + cl_user used to do. The only
remaining role for cl_count is to tell us if we are in a 'shutdown'
phase. We can provide that information using a single bit field instead
of a full atomic counter.

Also rename rpc_destroy_client() to rpc_close_client(), which reflects
better what its role is these days.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/clnt.h

@@ -25,7 +25,6 @@ struct rpc_inode;
  */
 struct rpc_clnt {
 	struct kref		cl_kref;	/* Number of references */
-	atomic_t		cl_count;	/* Number of clones */
 	struct list_head	cl_clients;	/* Global list of clients */
 	struct list_head	cl_tasks;	/* List of tasks */
 	spinlock_t		cl_lock;	/* spinlock */
@@ -119,8 +118,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args);
 struct rpc_clnt	*rpc_bind_new_program(struct rpc_clnt *,
 				struct rpc_program *, int);
 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *);
-int		rpc_shutdown_client(struct rpc_clnt *);
-int		rpc_destroy_client(struct rpc_clnt *);
+void		rpc_shutdown_client(struct rpc_clnt *);
 void		rpc_release_client(struct rpc_clnt *);
 void		rpc_register_client(struct rpc_clnt *);
 void		rpc_unregister_client(struct rpc_clnt *);

net/sunrpc/clnt.c

@@ -121,7 +121,6 @@ static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, s
 	clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
 	if (!clnt)
 		goto out_err;
-	atomic_set(&clnt->cl_count, 1);
 	clnt->cl_parent = clnt;
 
 	clnt->cl_server = clnt->cl_inline_name;
@@ -270,7 +269,6 @@ rpc_clone_client(struct rpc_clnt *clnt)
 	new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
 	if (!new)
 		goto out_no_clnt;
-	atomic_set(&new->cl_count, 1);
 	new->cl_metrics = rpc_alloc_iostats(clnt);
 	if (new->cl_metrics == NULL)
 		goto out_no_stats;
@@ -303,8 +301,7 @@ rpc_clone_client(struct rpc_clnt *clnt)
  * Properly shut down an RPC client, terminating all outstanding
  * requests.
  */
-int
-rpc_shutdown_client(struct rpc_clnt *clnt)
+void rpc_shutdown_client(struct rpc_clnt *clnt)
 {
 	dprintk("RPC:       shutting down %s client for %s\n",
 			clnt->cl_protname, clnt->cl_server);
@@ -315,7 +312,7 @@ rpc_shutdown_client(struct rpc_clnt *clnt)
 			list_empty(&clnt->cl_tasks), 1*HZ);
 	}
 
-	return rpc_destroy_client(clnt);
+	rpc_release_client(clnt);
 }
 
 /*
@@ -363,18 +360,6 @@ rpc_release_client(struct rpc_clnt *clnt)
 	kref_put(&clnt->cl_kref, rpc_free_client);
 }
 
-/*
- * Delete an RPC client
- */
-int
-rpc_destroy_client(struct rpc_clnt *clnt)
-{
-	if (!atomic_dec_and_test(&clnt->cl_count))
-		return 1;
-	kref_put(&clnt->cl_kref, rpc_free_client);
-	return 0;
-}
-
 /**
  * rpc_bind_new_program - bind a new RPC program to an existing client
  * @old - old rpc_client

net/sunrpc/rpcb_clnt.c

@@ -380,7 +380,7 @@ void rpcb_getport(struct rpc_task *task)
 	}
 
 	child = rpc_run_task(rpcb_clnt, RPC_TASK_ASYNC, &rpcb_getport_ops, map);
-	rpc_destroy_client(rpcb_clnt);
+	rpc_release_client(rpcb_clnt);
 	if (IS_ERR(child)) {
 		status = -EIO;
 		dprintk("RPC: %5u rpcb_getport rpc_run_task failed\n",

net/sunrpc/sunrpc_syms.c

@@ -35,7 +35,6 @@ EXPORT_SYMBOL(rpc_wake_up_status);
 /* RPC client functions */
 EXPORT_SYMBOL(rpc_clone_client);
 EXPORT_SYMBOL(rpc_bind_new_program);
-EXPORT_SYMBOL(rpc_destroy_client);
 EXPORT_SYMBOL(rpc_shutdown_client);
 EXPORT_SYMBOL(rpc_killall_tasks);
 EXPORT_SYMBOL(rpc_call_sync);