1 files changed, 60 insertions, 149 deletions

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 944d75396fb3..2ac43c41c3a9 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -25,7 +25,6 @@
 #ifdef RPC_DEBUG
 #define RPCDBG_FACILITY		RPCDBG_SCHED
 #define RPC_TASK_MAGIC_ID	0xf00baa
-static int			rpc_task_id;
 #endif
 
 /*
@@ -40,7 +39,6 @@ static mempool_t	*rpc_task_mempool __read_mostly;
 static mempool_t	*rpc_buffer_mempool __read_mostly;
 
 static void			__rpc_default_timer(struct rpc_task *task);
-static void			rpciod_killall(void);
 static void			rpc_async_schedule(struct work_struct *);
 static void			 rpc_release_task(struct rpc_task *task);
 
@@ -50,23 +48,13 @@ static void			 rpc_release_task(struct rpc_task *task);
 static RPC_WAITQ(delay_queue, "delayq");
 
 /*
- * All RPC tasks are linked into this list
- */
-static LIST_HEAD(all_tasks);
-
-/*
  * rpciod-related stuff
  */
 static DEFINE_MUTEX(rpciod_mutex);
-static unsigned int		rpciod_users;
+static atomic_t rpciod_users = ATOMIC_INIT(0);
 struct workqueue_struct *rpciod_workqueue;
 
 /*
- * Spinlock for other critical sections of code.
- */
-static DEFINE_SPINLOCK(rpc_sched_lock);
-
-/*
  * Disable the timer for a given RPC task. Should be called with
  * queue->lock and bh_disabled in order to avoid races within
  * rpc_run_timer().
@@ -267,18 +255,33 @@ static int rpc_wait_bit_interruptible(void *word)
 	return 0;
 }
 
+#ifdef RPC_DEBUG
+static void rpc_task_set_debuginfo(struct rpc_task *task)
+{
+	static atomic_t rpc_pid;
+
+	task->tk_magic = RPC_TASK_MAGIC_ID;
+	task->tk_pid = atomic_inc_return(&rpc_pid);
+}
+#else
+static inline void rpc_task_set_debuginfo(struct rpc_task *task)
+{
+}
+#endif
+
 static void rpc_set_active(struct rpc_task *task)
 {
+	struct rpc_clnt *clnt;
 	if (test_and_set_bit(RPC_TASK_ACTIVE, &task->tk_runstate) != 0)
 		return;
-	spin_lock(&rpc_sched_lock);
-#ifdef RPC_DEBUG
-	task->tk_magic = RPC_TASK_MAGIC_ID;
-	task->tk_pid = rpc_task_id++;
-#endif
+	rpc_task_set_debuginfo(task);
 	/* Add to global list of all tasks */
-	list_add_tail(&task->tk_task, &all_tasks);
-	spin_unlock(&rpc_sched_lock);
+	clnt = task->tk_client;
+	if (clnt != NULL) {
+		spin_lock(&clnt->cl_lock);
+		list_add_tail(&task->tk_task, &clnt->cl_tasks);
+		spin_unlock(&clnt->cl_lock);
+	}
 }
 
 /*
@@ -818,6 +821,7 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons
 	if (tk_ops->rpc_call_prepare != NULL)
 		task->tk_action = rpc_prepare_task;
 	task->tk_calldata = calldata;
+	INIT_LIST_HEAD(&task->tk_task);
 
 	/* Initialize retry counters */
 	task->tk_garb_retry = 2;
@@ -830,7 +834,7 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons
 	task->tk_workqueue = rpciod_workqueue;
 
 	if (clnt) {
-		atomic_inc(&clnt->cl_users);
+		kref_get(&clnt->cl_kref);
 		if (clnt->cl_softrtry)
 			task->tk_flags |= RPC_TASK_SOFT;
 		if (!clnt->cl_intr)
@@ -860,9 +864,7 @@ static void rpc_free_task(struct rcu_head *rcu)
 }
 
 /*
- * Create a new task for the specified client.  We have to
- * clean up after an allocation failure, as the client may
- * have specified "oneshot".
+ * Create a new task for the specified client.
  */
 struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata)
 {
@@ -870,7 +872,7 @@ struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc
 
 	task = rpc_alloc_task();
 	if (!task)
-		goto cleanup;
+		goto out;
 
 	rpc_init_task(task, clnt, flags, tk_ops, calldata);
 
@@ -878,16 +880,6 @@ struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc
 	task->tk_flags |= RPC_TASK_DYNAMIC;
 out:
 	return task;
-
-cleanup:
-	/* Check whether to release the client */
-	if (clnt) {
-		printk("rpc_new_task: failed, users=%d, oneshot=%d\n",
-			atomic_read(&clnt->cl_users), clnt->cl_oneshot);
-		atomic_inc(&clnt->cl_users); /* pretend we were used ... */
-		rpc_release_client(clnt);
-	}
-	goto out;
 }
 
 
@@ -920,11 +912,13 @@ static void rpc_release_task(struct rpc_task *task)
 #endif
 	dprintk("RPC: %5u release task\n", task->tk_pid);
 
-	/* Remove from global task list */
-	spin_lock(&rpc_sched_lock);
-	list_del(&task->tk_task);
-	spin_unlock(&rpc_sched_lock);
-
+	if (!list_empty(&task->tk_task)) {
+		struct rpc_clnt *clnt = task->tk_client;
+		/* Remove from client task list */
+		spin_lock(&clnt->cl_lock);
+		list_del(&task->tk_task);
+		spin_unlock(&clnt->cl_lock);
+	}
 	BUG_ON (RPC_IS_QUEUED(task));
 
 	/* Synchronously delete any running timer */
@@ -939,29 +933,6 @@ static void rpc_release_task(struct rpc_task *task)
 	rpc_put_task(task);
 }
 
-/**
- * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
- * @clnt: pointer to RPC client
- * @flags: RPC flags
- * @ops: RPC call ops
- * @data: user call data
- */
-struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
-					const struct rpc_call_ops *ops,
-					void *data)
-{
-	struct rpc_task *task;
-	task = rpc_new_task(clnt, flags, ops, data);
-	if (task == NULL) {
-		rpc_release_calldata(ops, data);
-		return ERR_PTR(-ENOMEM);
-	}
-	atomic_inc(&task->tk_count);
-	rpc_execute(task);
-	return task;
-}
-EXPORT_SYMBOL(rpc_run_task);
-
 /*
  * Kill all tasks for the given client.
  * XXX: kill their descendants as well?
@@ -969,44 +940,25 @@ EXPORT_SYMBOL(rpc_run_task);
 void rpc_killall_tasks(struct rpc_clnt *clnt)
 {
 	struct rpc_task	*rovr;
-	struct list_head *le;
 
-	dprintk("RPC:       killing all tasks for client %p\n", clnt);
 
+	if (list_empty(&clnt->cl_tasks))
+		return;
+	dprintk("RPC:       killing all tasks for client %p\n", clnt);
 	/*
 	 * Spin lock all_tasks to prevent changes...
 	 */
-	spin_lock(&rpc_sched_lock);
-	alltask_for_each(rovr, le, &all_tasks) {
+	spin_lock(&clnt->cl_lock);
+	list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
 		if (! RPC_IS_ACTIVATED(rovr))
 			continue;
-		if (!clnt || rovr->tk_client == clnt) {
+		if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
 			rovr->tk_flags |= RPC_TASK_KILLED;
 			rpc_exit(rovr, -EIO);
 			rpc_wake_up_task(rovr);
 		}
 	}
-	spin_unlock(&rpc_sched_lock);
-}
-
-static void rpciod_killall(void)
-{
-	unsigned long flags;
-
-	while (!list_empty(&all_tasks)) {
-		clear_thread_flag(TIF_SIGPENDING);
-		rpc_killall_tasks(NULL);
-		flush_workqueue(rpciod_workqueue);
-		if (!list_empty(&all_tasks)) {
-			dprintk("RPC:       rpciod_killall: waiting for tasks "
-					"to exit\n");
-			yield();
-		}
-	}
-
-	spin_lock_irqsave(&current->sighand->siglock, flags);
-	recalc_sigpending();
-	spin_unlock_irqrestore(&current->sighand->siglock, flags);
+	spin_unlock(&clnt->cl_lock);
 }
 
 /*
@@ -1018,28 +970,27 @@ rpciod_up(void)
 	struct workqueue_struct *wq;
 	int error = 0;
 
+	if (atomic_inc_not_zero(&rpciod_users))
+		return 0;
+
 	mutex_lock(&rpciod_mutex);
-	dprintk("RPC:       rpciod_up: users %u\n", rpciod_users);
-	rpciod_users++;
-	if (rpciod_workqueue)
-		goto out;
-	/*
-	 * If there's no pid, we should be the first user.
-	 */
-	if (rpciod_users > 1)
-		printk(KERN_WARNING "rpciod_up: no workqueue, %u users??\n", rpciod_users);
+
+	/* Guard against races with rpciod_down() */
+	if (rpciod_workqueue != NULL)
+		goto out_ok;
 	/*
 	 * Create the rpciod thread and wait for it to start.
 	 */
+	dprintk("RPC:       creating workqueue rpciod\n");
 	error = -ENOMEM;
 	wq = create_workqueue("rpciod");
-	if (wq == NULL) {
-		printk(KERN_WARNING "rpciod_up: create workqueue failed, error=%d\n", error);
-		rpciod_users--;
+	if (wq == NULL)
 		goto out;
-	}
+
 	rpciod_workqueue = wq;
 	error = 0;
+out_ok:
+	atomic_inc(&rpciod_users);
 out:
 	mutex_unlock(&rpciod_mutex);
 	return error;
@@ -1048,59 +999,19 @@ out:
 void
 rpciod_down(void)
 {
+	if (!atomic_dec_and_test(&rpciod_users))
+		return;
+
 	mutex_lock(&rpciod_mutex);
-	dprintk("RPC:       rpciod_down sema %u\n", rpciod_users);
-	if (rpciod_users) {
-		if (--rpciod_users)
-			goto out;
-	} else
-		printk(KERN_WARNING "rpciod_down: no users??\n");
+	dprintk("RPC:       destroying workqueue rpciod\n");
 
-	if (!rpciod_workqueue) {
-		dprintk("RPC:       rpciod_down: Nothing to do!\n");
-		goto out;
+	if (atomic_read(&rpciod_users) == 0 && rpciod_workqueue != NULL) {
+		destroy_workqueue(rpciod_workqueue);
+		rpciod_workqueue = NULL;
 	}
-	rpciod_killall();
-
-	destroy_workqueue(rpciod_workqueue);
-	rpciod_workqueue = NULL;
- out:
 	mutex_unlock(&rpciod_mutex);
 }
 
-#ifdef RPC_DEBUG
-void rpc_show_tasks(void)
-{
-	struct list_head *le;
-	struct rpc_task *t;
-
-	spin_lock(&rpc_sched_lock);
-	if (list_empty(&all_tasks)) {
-		spin_unlock(&rpc_sched_lock);
-		return;
-	}
-	printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
-		"-rpcwait -action- ---ops--\n");
-	alltask_for_each(t, le, &all_tasks) {
-		const char *rpc_waitq = "none";
-
-		if (RPC_IS_QUEUED(t))
-			rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
-
-		printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
-			t->tk_pid,
-			(t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1),
-			t->tk_flags, t->tk_status,
-			t->tk_client,
-			(t->tk_client ? t->tk_client->cl_prog : 0),
-			t->tk_rqstp, t->tk_timeout,
-			rpc_waitq,
-			t->tk_action, t->tk_ops);
-	}
-	spin_unlock(&rpc_sched_lock);
-}
-#endif
-
 void
 rpc_destroy_mempool(void)
 {