sysfs: don't use global workqueue in sysfs_schedule_callback()

[~andy/linux] / fs / sysfs / file.c

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 289c43a472634e5863c356502adeea451c0da882..979e9379fb5adf48ecc7dd8e46a3000445b12f4a 100644 (file)
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -667,6 +667,7 @@ struct sysfs_schedule_callback_struct {
        struct work_struct      work;
 };
 
+static struct workqueue_struct *sysfs_workqueue;
 static DEFINE_MUTEX(sysfs_workq_mutex);
 static LIST_HEAD(sysfs_workq);
 static void sysfs_schedule_callback_work(struct work_struct *work)
@@ -715,11 +716,20 @@ int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
        mutex_lock(&sysfs_workq_mutex);
        list_for_each_entry_safe(ss, tmp, &sysfs_workq, workq_list)
                if (ss->kobj == kobj) {
+                       module_put(owner);
                        mutex_unlock(&sysfs_workq_mutex);
                        return -EAGAIN;
                }
        mutex_unlock(&sysfs_workq_mutex);
 
+       if (sysfs_workqueue == NULL) {
+               sysfs_workqueue = create_workqueue("sysfsd");
+               if (sysfs_workqueue == NULL) {
+                       module_put(owner);
+                       return -ENOMEM;
+               }
+       }
+
        ss = kmalloc(sizeof(*ss), GFP_KERNEL);
        if (!ss) {
                module_put(owner);
@@ -735,7 +745,7 @@ int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
        mutex_lock(&sysfs_workq_mutex);
        list_add_tail(&ss->workq_list, &sysfs_workq);
        mutex_unlock(&sysfs_workq_mutex);
-       schedule_work(&ss->work);
+       queue_work(sysfs_workqueue, &ss->work);
        return 0;
 }
 EXPORT_SYMBOL_GPL(sysfs_schedule_callback);