USB: mark "reject" field of struct urb as atomic_t
It is enough to protect accesses to reject field of urb
by marking it as atomic_t,also it is the only reason of
existence of usb_reject_lock,so remove the lock to make
code more clean.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 1f68af9..b5e9948 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -10,7 +10,6 @@
#define to_urb(d) container_of(d, struct urb, kref)
-static DEFINE_SPINLOCK(usb_reject_lock);
static void urb_destroy(struct kref *kref)
{
@@ -131,9 +130,7 @@
urb->anchor = anchor;
if (unlikely(anchor->poisoned)) {
- spin_lock(&usb_reject_lock);
- urb->reject++;
- spin_unlock(&usb_reject_lock);
+ atomic_inc(&urb->reject);
}
spin_unlock_irqrestore(&anchor->lock, flags);
@@ -565,16 +562,12 @@
might_sleep();
if (!(urb && urb->dev && urb->ep))
return;
- spin_lock_irq(&usb_reject_lock);
- ++urb->reject;
- spin_unlock_irq(&usb_reject_lock);
+ atomic_inc(&urb->reject);
usb_hcd_unlink_urb(urb, -ENOENT);
wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0);
- spin_lock_irq(&usb_reject_lock);
- --urb->reject;
- spin_unlock_irq(&usb_reject_lock);
+ atomic_dec(&urb->reject);
}
EXPORT_SYMBOL_GPL(usb_kill_urb);
@@ -606,9 +599,7 @@
might_sleep();
if (!(urb && urb->dev && urb->ep))
return;
- spin_lock_irq(&usb_reject_lock);
- ++urb->reject;
- spin_unlock_irq(&usb_reject_lock);
+ atomic_inc(&urb->reject);
usb_hcd_unlink_urb(urb, -ENOENT);
wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0);
@@ -617,14 +608,10 @@
void usb_unpoison_urb(struct urb *urb)
{
- unsigned long flags;
-
if (!urb)
return;
- spin_lock_irqsave(&usb_reject_lock, flags);
- --urb->reject;
- spin_unlock_irqrestore(&usb_reject_lock, flags);
+ atomic_dec(&urb->reject);
}
EXPORT_SYMBOL_GPL(usb_unpoison_urb);