2.6.26-rc1-git7

 kernel

diff --git a/kernel/semaphore.c b/kernel/semaphore.c
index 5c2942e..5e41217 100644
--- a/kernel/semaphore.c
+++ b/kernel/semaphore.c
@@ -54,10 +54,9 @@ void down(struct semaphore *sem)
    unsigned long flags;
 
    spin_lock_irqsave(&sem->lock, flags);
-   if (likely(sem->count > 0))
-      sem->count--;
-   else
+   if (unlikely(!sem->count))
       __down(sem);
+   sem->count--;
    spin_unlock_irqrestore(&sem->lock, flags);
 }
 EXPORT_SYMBOL(down);
@@ -77,10 +76,10 @@ int down_interruptible(struct semaphore *sem)
    int result = 0;
 
    spin_lock_irqsave(&sem->lock, flags);
-   if (likely(sem->count > 0))
-      sem->count--;
-   else
+   if (unlikely(!sem->count))
       result = __down_interruptible(sem);
+   if (!result)
+      sem->count--;
    spin_unlock_irqrestore(&sem->lock, flags);
 
    return result;
@@ -103,10 +102,10 @@ int down_killable(struct semaphore *sem)
    int result = 0;
 
    spin_lock_irqsave(&sem->lock, flags);
-   if (likely(sem->count > 0))
-      sem->count--;
-   else
+   if (unlikely(!sem->count))
       result = __down_killable(sem);
+   if (!result)
+      sem->count--;
    spin_unlock_irqrestore(&sem->lock, flags);
 
    return result;
@@ -157,10 +156,10 @@ int down_timeout(struct semaphore *sem, long jiffies)
    int result = 0;
 
    spin_lock_irqsave(&sem->lock, flags);
-   if (likely(sem->count > 0))
-      sem->count--;
-   else
+   if (unlikely(!sem->count))
       result = __down_timeout(sem, jiffies);
+   if (!result)
+      sem->count--;
    spin_unlock_irqrestore(&sem->lock, flags);
 
    return result;
@@ -179,9 +178,8 @@ void up(struct semaphore *sem)
    unsigned long flags;
 
    spin_lock_irqsave(&sem->lock, flags);
-   if (likely(list_empty(&sem->wait_list)))
-      sem->count++;
-   else
+   sem->count++;
+   if (unlikely(!list_empty(&sem->wait_list)))
       __up(sem);
    spin_unlock_irqrestore(&sem->lock, flags);
 }
@@ -192,7 +190,6 @@ EXPORT_SYMBOL(up);
 struct semaphore_waiter {
    struct list_head list;
    struct task_struct *task;
-   int up;
 };
 
 /*
@@ -205,33 +202,34 @@ static inline int __sched __down_common(struct semaphore *sem, long state,
 {
    struct task_struct *task = current;
    struct semaphore_waiter waiter;
+   int ret = 0;
 
-   list_add_tail(&waiter.list, &sem->wait_list);
    waiter.task = task;
-   waiter.up = 0;
+   list_add_tail(&waiter.list, &sem->wait_list);
 
    for (;;) {
-      if (state == TASK_INTERRUPTIBLE && signal_pending(task))
-         goto interrupted;
-      if (state == TASK_KILLABLE && fatal_signal_pending(task))
-         goto interrupted;
-      if (timeout <= 0)
-         goto timed_out;
+      if (state == TASK_INTERRUPTIBLE && signal_pending(task)) {
+         ret = -EINTR;
+         break;
+      }
+      if (state == TASK_KILLABLE && fatal_signal_pending(task)) {
+         ret = -EINTR;
+         break;
+      }
+      if (timeout <= 0) {
+         ret = -ETIME;
+         break;
+      }
       __set_task_state(task, state);
       spin_unlock_irq(&sem->lock);
       timeout = schedule_timeout(timeout);
       spin_lock_irq(&sem->lock);
-      if (waiter.up)
-         return 0;
+      if (sem->count > 0)
+         break;
    }
 
- timed_out:
-   list_del(&waiter.list);
-   return -ETIME;
-
- interrupted:
    list_del(&waiter.list);
-   return -EINTR;
+   return ret;
 }
 
 static noinline void __sched __down(struct semaphore *sem)
@@ -258,7 +256,5 @@ static noinline void __sched __up(struct semaphore *sem)
 {
    struct semaphore_waiter *waiter = list_first_entry(&sem->wait_list,
                   struct semaphore_waiter, list);
-   list_del(&waiter->list);
-   waiter->up = 1;
    wake_up_process(waiter->task);
 }