Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/include/asm-arm26/semaphore-helper.h b/include/asm-arm26/semaphore-helper.h
new file mode 100644
index 0000000..1d7f198
--- /dev/null
+++ b/include/asm-arm26/semaphore-helper.h
@@ -0,0 +1,84 @@
+#ifndef ASMARM_SEMAPHORE_HELPER_H
+#define ASMARM_SEMAPHORE_HELPER_H
+
+/*
+ * These two _must_ execute atomically wrt each other.
+ */
+static inline void wake_one_more(struct semaphore * sem)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&semaphore_wake_lock, flags);
+ if (atomic_read(&sem->count) <= 0)
+ sem->waking++;
+ spin_unlock_irqrestore(&semaphore_wake_lock, flags);
+}
+
+static inline int waking_non_zero(struct semaphore *sem)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&semaphore_wake_lock, flags);
+ if (sem->waking > 0) {
+ sem->waking--;
+ ret = 1;
+ }
+ spin_unlock_irqrestore(&semaphore_wake_lock, flags);
+ return ret;
+}
+
+/*
+ * waking non zero interruptible
+ * 1 got the lock
+ * 0 go to sleep
+ * -EINTR interrupted
+ *
+ * We must undo the sem->count down_interruptible() increment while we are
+ * protected by the spinlock in order to make this atomic_inc() with the
+ * atomic_read() in wake_one_more(), otherwise we can race. -arca
+ */
+static inline int waking_non_zero_interruptible(struct semaphore *sem,
+ struct task_struct *tsk)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&semaphore_wake_lock, flags);
+ if (sem->waking > 0) {
+ sem->waking--;
+ ret = 1;
+ } else if (signal_pending(tsk)) {
+ atomic_inc(&sem->count);
+ ret = -EINTR;
+ }
+ spin_unlock_irqrestore(&semaphore_wake_lock, flags);
+ return ret;
+}
+
+/*
+ * waking_non_zero_try_lock:
+ * 1 failed to lock
+ * 0 got the lock
+ *
+ * We must undo the sem->count down_interruptible() increment while we are
+ * protected by the spinlock in order to make this atomic_inc() with the
+ * atomic_read() in wake_one_more(), otherwise we can race. -arca
+ */
+static inline int waking_non_zero_trylock(struct semaphore *sem)
+{
+ unsigned long flags;
+ int ret = 1;
+
+ spin_lock_irqsave(&semaphore_wake_lock, flags);
+ if (sem->waking <= 0)
+ atomic_inc(&sem->count);
+ else {
+ sem->waking--;
+ ret = 0;
+ }
+ spin_unlock_irqrestore(&semaphore_wake_lock, flags);
+ return ret;
+}
+
+#endif