[media] tm6000: Use just one lock for devlist
authorMauro Carvalho Chehab <mchehab@redhat.com>
Mon, 11 Oct 2010 12:57:34 +0000 (09:57 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Thu, 21 Oct 2010 13:36:18 +0000 (11:36 -0200)
This avoids a race condition

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/staging/tm6000/tm6000-core.c

index af41bbe..bfaaaa7 100644 (file)
@@ -644,7 +644,6 @@ void tm6000_add_into_devlist(struct tm6000_core *dev)
  */
 
 static LIST_HEAD(tm6000_extension_devlist);
-static DEFINE_MUTEX(tm6000_extension_devlist_lock);
 
 int tm6000_call_fillbuf(struct tm6000_core *dev, enum tm6000_ops_type type,
                        char *buf, int size)
@@ -668,14 +667,12 @@ int tm6000_register_extension(struct tm6000_ops *ops)
        struct tm6000_core *dev = NULL;
 
        mutex_lock(&tm6000_devlist_mutex);
-       mutex_lock(&tm6000_extension_devlist_lock);
        list_add_tail(&ops->next, &tm6000_extension_devlist);
        list_for_each_entry(dev, &tm6000_devlist, devlist) {
                ops->init(dev);
                printk(KERN_INFO "%s: Initialized (%s) extension\n",
                       dev->name, ops->name);
        }
-       mutex_unlock(&tm6000_extension_devlist_lock);
        mutex_unlock(&tm6000_devlist_mutex);
        return 0;
 }
@@ -691,10 +688,8 @@ void tm6000_unregister_extension(struct tm6000_ops *ops)
                        ops->fini(dev);
        }
 
-       mutex_lock(&tm6000_extension_devlist_lock);
        printk(KERN_INFO "tm6000: Remove (%s) extension\n", ops->name);
        list_del(&ops->next);
-       mutex_unlock(&tm6000_extension_devlist_lock);
        mutex_unlock(&tm6000_devlist_mutex);
 }
 EXPORT_SYMBOL(tm6000_unregister_extension);
@@ -703,26 +698,26 @@ void tm6000_init_extension(struct tm6000_core *dev)
 {
        struct tm6000_ops *ops = NULL;
 
-       mutex_lock(&tm6000_extension_devlist_lock);
+       mutex_lock(&tm6000_devlist_mutex);
        if (!list_empty(&tm6000_extension_devlist)) {
                list_for_each_entry(ops, &tm6000_extension_devlist, next) {
                        if (ops->init)
                                ops->init(dev);
                }
        }
-       mutex_unlock(&tm6000_extension_devlist_lock);
+       mutex_unlock(&tm6000_devlist_mutex);
 }
 
 void tm6000_close_extension(struct tm6000_core *dev)
 {
        struct tm6000_ops *ops = NULL;
 
-       mutex_lock(&tm6000_extension_devlist_lock);
+       mutex_lock(&tm6000_devlist_mutex);
        if (!list_empty(&tm6000_extension_devlist)) {
                list_for_each_entry(ops, &tm6000_extension_devlist, next) {
                        if (ops->fini)
                                ops->fini(dev);
                }
        }
-       mutex_unlock(&tm6000_extension_devlist_lock);
+       mutex_lock(&tm6000_devlist_mutex);
 }