From: Ming Lei <[email protected]>
smp_mb is enough for ordering memory operations among processors,and
mb is more expensive than smp_mb for UP machine, so replace it with
smp_mb().
Signed-off-by: Ming Lei <[email protected]>
---
drivers/bluetooth/hci_usb.h | 10 +++++-----
1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/bluetooth/hci_usb.h b/drivers/bluetooth/hci_usb.h
index 1790cc8..8e65991 100644
--- a/drivers/bluetooth/hci_usb.h
+++ b/drivers/bluetooth/hci_usb.h
@@ -70,8 +70,8 @@ static inline void _urb_queue_head(struct _urb_queue *q, struct _urb *_urb)
{
unsigned long flags;
spin_lock_irqsave(&q->lock, flags);
- /* _urb_unlink needs to know which spinlock to use, thus mb(). */
- _urb->queue = q; mb(); list_add(&_urb->list, &q->head);
+ /* _urb_unlink needs to know which spinlock to use, thus smp_mb(). */
+ _urb->queue = q; smp_mb(); list_add(&_urb->list, &q->head);
spin_unlock_irqrestore(&q->lock, flags);
}
@@ -79,8 +79,8 @@ static inline void _urb_queue_tail(struct _urb_queue *q, struct _urb *_urb)
{
unsigned long flags;
spin_lock_irqsave(&q->lock, flags);
- /* _urb_unlink needs to know which spinlock to use, thus mb(). */
- _urb->queue = q; mb(); list_add_tail(&_urb->list, &q->head);
+ /* _urb_unlink needs to know which spinlock to use, thus smp_mb(). */
+ _urb->queue = q; smp_mb(); list_add_tail(&_urb->list, &q->head);
spin_unlock_irqrestore(&q->lock, flags);
}
@@ -89,7 +89,7 @@ static inline void _urb_unlink(struct _urb *_urb)
struct _urb_queue *q;
unsigned long flags;
- mb();
+ smp_mb();
q = _urb->queue;
/* If q is NULL, it will die at easy-to-debug NULL pointer dereference.
No need to BUG(). */
--
1.5.6.rc2.45.gdc92c