diff options
| author | Ming Lei <tom.leiming@gmail.com> | 2008-09-22 19:21:51 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-09-22 19:21:51 -0700 |
| commit | ca330c5a913a9b1690c709f4cfcd6be0c8696b14 (patch) | |
| tree | 372e4320da2dea602dc9c26ff2411cd82260fedb | |
| parent | d48abfecea8513cfd2fd7e341439c1b8a28e9ff4 (diff) | |
hci_usb: replace mb with smp_mb
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 <tom.leiming@gmail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | 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 1790cc8e431..8e659914523 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(). */ |