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-alpha/semaphore.h b/include/asm-alpha/semaphore.h
new file mode 100644
index 0000000..eb2cbd9
--- /dev/null
+++ b/include/asm-alpha/semaphore.h
@@ -0,0 +1,153 @@
+#ifndef _ALPHA_SEMAPHORE_H
+#define _ALPHA_SEMAPHORE_H
+
+/*
+ * SMP- and interrupt-safe semaphores..
+ *
+ * (C) Copyright 1996 Linus Torvalds
+ * (C) Copyright 1996, 2000 Richard Henderson
+ */
+
+#include <asm/current.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+#include <linux/compiler.h>
+#include <linux/wait.h>
+#include <linux/rwsem.h>
+
+struct semaphore {
+ atomic_t count;
+ wait_queue_head_t wait;
+};
+
+#define __SEMAPHORE_INITIALIZER(name, n) \
+{ \
+ .count = ATOMIC_INIT(n), \
+ .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \
+}
+
+#define __MUTEX_INITIALIZER(name) \
+ __SEMAPHORE_INITIALIZER(name,1)
+
+#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
+ struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
+
+#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
+#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
+
+static inline void sema_init(struct semaphore *sem, int val)
+{
+ /*
+ * Logically,
+ * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val);
+ * except that gcc produces better initializing by parts yet.
+ */
+
+ atomic_set(&sem->count, val);
+ init_waitqueue_head(&sem->wait);
+}
+
+static inline void init_MUTEX (struct semaphore *sem)
+{
+ sema_init(sem, 1);
+}
+
+static inline void init_MUTEX_LOCKED (struct semaphore *sem)
+{
+ sema_init(sem, 0);
+}
+
+extern void down(struct semaphore *);
+extern void __down_failed(struct semaphore *);
+extern int down_interruptible(struct semaphore *);
+extern int __down_failed_interruptible(struct semaphore *);
+extern int down_trylock(struct semaphore *);
+extern void up(struct semaphore *);
+extern void __up_wakeup(struct semaphore *);
+
+/*
+ * Hidden out of line code is fun, but extremely messy. Rely on newer
+ * compilers to do a respectable job with this. The contention cases
+ * are handled out of line in arch/alpha/kernel/semaphore.c.
+ */
+
+static inline void __down(struct semaphore *sem)
+{
+ long count;
+ might_sleep();
+ count = atomic_dec_return(&sem->count);
+ if (unlikely(count < 0))
+ __down_failed(sem);
+}
+
+static inline int __down_interruptible(struct semaphore *sem)
+{
+ long count;
+ might_sleep();
+ count = atomic_dec_return(&sem->count);
+ if (unlikely(count < 0))
+ return __down_failed_interruptible(sem);
+ return 0;
+}
+
+/*
+ * down_trylock returns 0 on success, 1 if we failed to get the lock.
+ */
+
+static inline int __down_trylock(struct semaphore *sem)
+{
+ long ret;
+
+ /* "Equivalent" C:
+
+ do {
+ ret = ldl_l;
+ --ret;
+ if (ret < 0)
+ break;
+ ret = stl_c = ret;
+ } while (ret == 0);
+ */
+ __asm__ __volatile__(
+ "1: ldl_l %0,%1\n"
+ " subl %0,1,%0\n"
+ " blt %0,2f\n"
+ " stl_c %0,%1\n"
+ " beq %0,3f\n"
+ " mb\n"
+ "2:\n"
+ ".subsection 2\n"
+ "3: br 1b\n"
+ ".previous"
+ : "=&r" (ret), "=m" (sem->count)
+ : "m" (sem->count));
+
+ return ret < 0;
+}
+
+static inline void __up(struct semaphore *sem)
+{
+ if (unlikely(atomic_inc_return(&sem->count) <= 0))
+ __up_wakeup(sem);
+}
+
+#if !defined(CONFIG_DEBUG_SEMAPHORE)
+extern inline void down(struct semaphore *sem)
+{
+ __down(sem);
+}
+extern inline int down_interruptible(struct semaphore *sem)
+{
+ return __down_interruptible(sem);
+}
+extern inline int down_trylock(struct semaphore *sem)
+{
+ return __down_trylock(sem);
+}
+extern inline void up(struct semaphore *sem)
+{
+ __up(sem);
+}
+#endif
+
+#endif
