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>

1 files changed, 5 insertions, 18 deletions

diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 1f68af9db3f..b5e9948698b 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 @@ void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor)
         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 @@ void usb_kill_urb(struct urb *urb)
         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 @@ void usb_poison_urb(struct urb *urb)
         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 @@ EXPORT_SYMBOL_GPL(usb_poison_urb);
 
 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);