X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=kernel%2Fkthread.c;h=36fd751a769f4839100a54e2027ad57bb38ed117;hb=255451e45345bcd19e79f25e9afc0b9e14ccb104;hp=4ab4c3766a80ddf917cb988ac9c55d48957edbc4;hpb=b4f33f6ddd0c218e12454e1379de3aaa73f2e8dc;p=cascardo%2Flinux.git

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 4ab4c3766a80..36fd751a769f 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -138,7 +138,7 @@ void *kthread_data(struct task_struct *task)
 }
 
 /**
- * probe_kthread_data - speculative version of kthread_data()
+ * kthread_probe_data - speculative version of kthread_data()
  * @task: possible kthread task in question
  *
  * @task could be a kthread task.  Return the data value specified when it
@@ -146,7 +146,7 @@ void *kthread_data(struct task_struct *task)
  * inaccessible for any reason, %NULL is returned.  This function requires
  * that @task itself is safe to dereference.
  */
-void *probe_kthread_data(struct task_struct *task)
+void *kthread_probe_data(struct task_struct *task)
 {
 	struct kthread *kthread = to_kthread(task);
 	void *data = NULL;
@@ -244,33 +244,10 @@ static void create_kthread(struct kthread_create_info *create)
 	}
 }
 
-/**
- * kthread_create_on_node - create a kthread.
- * @threadfn: the function to run until signal_pending(current).
- * @data: data ptr for @threadfn.
- * @node: task and thread structures for the thread are allocated on this node
- * @namefmt: printf-style name for the thread.
- *
- * Description: This helper function creates and names a kernel
- * thread.  The thread will be stopped: use wake_up_process() to start
- * it.  See also kthread_run().  The new thread has SCHED_NORMAL policy and
- * is affine to all CPUs.
- *
- * If thread is going to be bound on a particular cpu, give its node
- * in @node, to get NUMA affinity for kthread stack, or else give NUMA_NO_NODE.
- * When woken, the thread will run @threadfn() with @data as its
- * argument. @threadfn() can either call do_exit() directly if it is a
- * standalone thread for which no one will call kthread_stop(), or
- * return when 'kthread_should_stop()' is true (which means
- * kthread_stop() has been called).  The return value should be zero
- * or a negative error number; it will be passed to kthread_stop().
- *
- * Returns a task_struct or ERR_PTR(-ENOMEM) or ERR_PTR(-EINTR).
- */
-struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
-					   void *data, int node,
-					   const char namefmt[],
-					   ...)
+static struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data),
+						    void *data, int node,
+						    const char namefmt[],
+						    va_list args)
 {
 	DECLARE_COMPLETION_ONSTACK(done);
 	struct task_struct *task;
@@ -311,11 +288,8 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
 	task = create->result;
 	if (!IS_ERR(task)) {
 		static const struct sched_param param = { .sched_priority = 0 };
-		va_list args;
 
-		va_start(args, namefmt);
 		vsnprintf(task->comm, sizeof(task->comm), namefmt, args);
-		va_end(args);
 		/*
 		 * root may have changed our (kthreadd's) priority or CPU mask.
 		 * The kernel thread should not inherit these properties.
@@ -326,6 +300,44 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
 	kfree(create);
 	return task;
 }
+
+/**
+ * kthread_create_on_node - create a kthread.
+ * @threadfn: the function to run until signal_pending(current).
+ * @data: data ptr for @threadfn.
+ * @node: task and thread structures for the thread are allocated on this node
+ * @namefmt: printf-style name for the thread.
+ *
+ * Description: This helper function creates and names a kernel
+ * thread.  The thread will be stopped: use wake_up_process() to start
+ * it.  See also kthread_run().  The new thread has SCHED_NORMAL policy and
+ * is affine to all CPUs.
+ *
+ * If thread is going to be bound on a particular cpu, give its node
+ * in @node, to get NUMA affinity for kthread stack, or else give NUMA_NO_NODE.
+ * When woken, the thread will run @threadfn() with @data as its
+ * argument. @threadfn() can either call do_exit() directly if it is a
+ * standalone thread for which no one will call kthread_stop(), or
+ * return when 'kthread_should_stop()' is true (which means
+ * kthread_stop() has been called).  The return value should be zero
+ * or a negative error number; it will be passed to kthread_stop().
+ *
+ * Returns a task_struct or ERR_PTR(-ENOMEM) or ERR_PTR(-EINTR).
+ */
+struct task_struct *kthread_create_on_node(int (*threadfn)(void *data),
+					   void *data, int node,
+					   const char namefmt[],
+					   ...)
+{
+	struct task_struct *task;
+	va_list args;
+
+	va_start(args, namefmt);
+	task = __kthread_create_on_node(threadfn, data, node, namefmt, args);
+	va_end(args);
+
+	return task;
+}
 EXPORT_SYMBOL(kthread_create_on_node);
 
 static void __kthread_bind_mask(struct task_struct *p, const struct cpumask *mask, long state)
@@ -390,10 +402,10 @@ struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data),
 				   cpu);
 	if (IS_ERR(p))
 		return p;
+	kthread_bind(p, cpu);
+	/* CPU hotplug need to bind once again when unparking the thread. */
 	set_bit(KTHREAD_IS_PER_CPU, &to_kthread(p)->flags);
 	to_kthread(p)->cpu = cpu;
-	/* Park the thread to get it out of TASK_UNINTERRUPTIBLE state */
-	kthread_park(p);
 	return p;
 }
 
@@ -407,6 +419,10 @@ static void __kthread_unpark(struct task_struct *k, struct kthread *kthread)
 	 * which might be about to be cleared.
 	 */
 	if (test_and_clear_bit(KTHREAD_IS_PARKED, &kthread->flags)) {
+		/*
+		 * Newly created kthread was parked when the CPU was offline.
+		 * The binding was lost and we need to set it again.
+		 */
 		if (test_bit(KTHREAD_IS_PER_CPU, &kthread->flags))
 			__kthread_bind(k, kthread->cpu, TASK_PARKED);
 		wake_up_state(k, TASK_PARKED);
@@ -540,7 +556,7 @@ int kthreadd(void *unused)
 	return 0;
 }
 
-void __init_kthread_worker(struct kthread_worker *worker,
+void __kthread_init_worker(struct kthread_worker *worker,
 				const char *name,
 				struct lock_class_key *key)
 {
@@ -549,7 +565,7 @@ void __init_kthread_worker(struct kthread_worker *worker,
 	INIT_LIST_HEAD(&worker->work_list);
 	worker->task = NULL;
 }
-EXPORT_SYMBOL_GPL(__init_kthread_worker);
+EXPORT_SYMBOL_GPL(__kthread_init_worker);
 
 /**
  * kthread_worker_fn - kthread function to process kthread_worker
@@ -606,7 +622,7 @@ repeat:
 EXPORT_SYMBOL_GPL(kthread_worker_fn);
 
 /* insert @work before @pos in @worker */
-static void insert_kthread_work(struct kthread_worker *worker,
+static void kthread_insert_work(struct kthread_worker *worker,
 			       struct kthread_work *work,
 			       struct list_head *pos)
 {
@@ -619,7 +635,7 @@ static void insert_kthread_work(struct kthread_worker *worker,
 }
 
 /**
- * queue_kthread_work - queue a kthread_work
+ * kthread_queue_work - queue a kthread_work
  * @worker: target kthread_worker
  * @work: kthread_work to queue
  *
@@ -627,7 +643,7 @@ static void insert_kthread_work(struct kthread_worker *worker,
  * must have been created with kthread_worker_create().  Returns %true
  * if @work was successfully queued, %false if it was already pending.
  */
-bool queue_kthread_work(struct kthread_worker *worker,
+bool kthread_queue_work(struct kthread_worker *worker,
 			struct kthread_work *work)
 {
 	bool ret = false;
@@ -635,13 +651,13 @@ bool queue_kthread_work(struct kthread_worker *worker,
 
 	spin_lock_irqsave(&worker->lock, flags);
 	if (list_empty(&work->node)) {
-		insert_kthread_work(worker, work, &worker->work_list);
+		kthread_insert_work(worker, work, &worker->work_list);
 		ret = true;
 	}
 	spin_unlock_irqrestore(&worker->lock, flags);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(queue_kthread_work);
+EXPORT_SYMBOL_GPL(kthread_queue_work);
 
 struct kthread_flush_work {
 	struct kthread_work	work;
@@ -656,12 +672,12 @@ static void kthread_flush_work_fn(struct kthread_work *work)
 }
 
 /**
- * flush_kthread_work - flush a kthread_work
+ * kthread_flush_work - flush a kthread_work
  * @work: work to flush
  *
  * If @work is queued or executing, wait for it to finish execution.
  */
-void flush_kthread_work(struct kthread_work *work)
+void kthread_flush_work(struct kthread_work *work)
 {
 	struct kthread_flush_work fwork = {
 		KTHREAD_WORK_INIT(fwork.work, kthread_flush_work_fn),
@@ -682,9 +698,10 @@ retry:
 	}
 
 	if (!list_empty(&work->node))
-		insert_kthread_work(worker, &fwork.work, work->node.next);
+		kthread_insert_work(worker, &fwork.work, work->node.next);
 	else if (worker->current_work == work)
-		insert_kthread_work(worker, &fwork.work, worker->work_list.next);
+		kthread_insert_work(worker, &fwork.work,
+				    worker->work_list.next);
 	else
 		noop = true;
 
@@ -693,23 +710,23 @@ retry:
 	if (!noop)
 		wait_for_completion(&fwork.done);
 }
-EXPORT_SYMBOL_GPL(flush_kthread_work);
+EXPORT_SYMBOL_GPL(kthread_flush_work);
 
 /**
- * flush_kthread_worker - flush all current works on a kthread_worker
+ * kthread_flush_worker - flush all current works on a kthread_worker
  * @worker: worker to flush
  *
  * Wait until all currently executing or pending works on @worker are
  * finished.
  */
-void flush_kthread_worker(struct kthread_worker *worker)
+void kthread_flush_worker(struct kthread_worker *worker)
 {
 	struct kthread_flush_work fwork = {
 		KTHREAD_WORK_INIT(fwork.work, kthread_flush_work_fn),
 		COMPLETION_INITIALIZER_ONSTACK(fwork.done),
 	};
 
-	queue_kthread_work(worker, &fwork.work);
+	kthread_queue_work(worker, &fwork.work);
 	wait_for_completion(&fwork.done);
 }
-EXPORT_SYMBOL_GPL(flush_kthread_worker);
+EXPORT_SYMBOL_GPL(kthread_flush_worker);