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-mips/semaphore.h b/include/asm-mips/semaphore.h
new file mode 100644
index 0000000..c2c97de
--- /dev/null
+++ b/include/asm-mips/semaphore.h
@@ -0,0 +1,112 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1996 Linus Torvalds
+ * Copyright (C) 1998, 99, 2000, 01, 04 Ralf Baechle
+ * Copyright (C) 1999, 2000, 01 Silicon Graphics, Inc.
+ * Copyright (C) 2000, 01 MIPS Technologies, Inc.
+ *
+ * In all honesty, little of the old MIPS code left - the PPC64 variant was
+ * just looking nice and portable so I ripped it. Credits to whoever wrote
+ * it.
+ */
+#ifndef __ASM_SEMAPHORE_H
+#define __ASM_SEMAPHORE_H
+
+/*
+ * Remove spinlock-based RW semaphores; RW semaphore definitions are
+ * now in rwsem.h and we use the generic lib/rwsem.c implementation.
+ * Rework semaphores to use atomic_dec_if_positive.
+ * -- Paul Mackerras (paulus@samba.org)
+ */
+
+#ifdef __KERNEL__
+
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <linux/wait.h>
+#include <linux/rwsem.h>
+
+struct semaphore {
+ /*
+ * Note that any negative value of count is equivalent to 0,
+ * but additionally indicates that some process(es) might be
+ * sleeping on `wait'.
+ */
+ 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)
+{
+ 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 * sem);
+extern int __down_interruptible(struct semaphore * sem);
+extern void __up(struct semaphore * sem);
+
+static inline void down(struct semaphore * sem)
+{
+ might_sleep();
+
+ /*
+ * Try to get the semaphore, take the slow path if we fail.
+ */
+ if (unlikely(atomic_dec_return(&sem->count) < 0))
+ __down(sem);
+}
+
+static inline int down_interruptible(struct semaphore * sem)
+{
+ int ret = 0;
+
+ might_sleep();
+
+ if (unlikely(atomic_dec_return(&sem->count) < 0))
+ ret = __down_interruptible(sem);
+ return ret;
+}
+
+static inline int down_trylock(struct semaphore * sem)
+{
+ return atomic_dec_if_positive(&sem->count) < 0;
+}
+
+static inline void up(struct semaphore * sem)
+{
+ if (unlikely(atomic_inc_return(&sem->count) <= 0))
+ __up(sem);
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_SEMAPHORE_H */