Generic semaphore implementation

Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility.  Thanks to Peter Zijlstra for fixing the lockdep
warning.  Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 0 insertions, 142 deletions

diff --git a/include/asm-m68k/semaphore-helper.h b/include/asm-m68k/semaphore-helper.h
deleted file mode 100644
index eef30ba0b49..00000000000
--- a/include/asm-m68k/semaphore-helper.h
+++ /dev/null
@@ -1,142 +0,0 @@
-#ifndef _M68K_SEMAPHORE_HELPER_H
-#define _M68K_SEMAPHORE_HELPER_H
-
-/*
- * SMP- and interrupt-safe semaphores helper functions.
- *
- * (C) Copyright 1996 Linus Torvalds
- *
- * m68k version by Andreas Schwab
- */
-
-#include <linux/errno.h>
-
-/*
- * These two _must_ execute atomically wrt each other.
- */
-static inline void wake_one_more(struct semaphore * sem)
-{
-	atomic_inc(&sem->waking);
-}
-
-#ifndef CONFIG_RMW_INSNS
-extern spinlock_t semaphore_wake_lock;
-#endif
-
-static inline int waking_non_zero(struct semaphore *sem)
-{
-	int ret;
-#ifndef CONFIG_RMW_INSNS
-	unsigned long flags;
-
-	spin_lock_irqsave(&semaphore_wake_lock, flags);
-	ret = 0;
-	if (atomic_read(&sem->waking) > 0) {
-		atomic_dec(&sem->waking);
-		ret = 1;
-	}
-	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
-#else
-	int tmp1, tmp2;
-
-	__asm__ __volatile__
-	  ("1:	movel	%1,%2\n"
-	   "    jle	2f\n"
-	   "	subql	#1,%2\n"
-	   "	casl	%1,%2,%3\n"
-	   "	jne	1b\n"
-	   "	moveq	#1,%0\n"
-	   "2:"
-	   : "=d" (ret), "=d" (tmp1), "=d" (tmp2)
-	   : "m" (sem->waking), "0" (0), "1" (sem->waking));
-#endif
-
-	return ret;
-}
-
-/*
- * waking_non_zero_interruptible:
- *	1	got the lock
- *	0	go to sleep
- *	-EINTR	interrupted
- */
-static inline int waking_non_zero_interruptible(struct semaphore *sem,
-						struct task_struct *tsk)
-{
-	int ret;
-#ifndef CONFIG_RMW_INSNS
-	unsigned long flags;
-
-	spin_lock_irqsave(&semaphore_wake_lock, flags);
-	ret = 0;
-	if (atomic_read(&sem->waking) > 0) {
-		atomic_dec(&sem->waking);
-		ret = 1;
-	} else if (signal_pending(tsk)) {
-		atomic_inc(&sem->count);
-		ret = -EINTR;
-	}
-	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
-#else
-	int tmp1, tmp2;
-
-	__asm__ __volatile__
-	  ("1:	movel	%1,%2\n"
-	   "	jle	2f\n"
-	   "	subql	#1,%2\n"
-	   "	casl	%1,%2,%3\n"
-	   "	jne	1b\n"
-	   "	moveq	#1,%0\n"
-	   "	jra	%a4\n"
-	   "2:"
-	   : "=d" (ret), "=d" (tmp1), "=d" (tmp2)
-	   : "m" (sem->waking), "i" (&&next), "0" (0), "1" (sem->waking));
-	if (signal_pending(tsk)) {
-		atomic_inc(&sem->count);
-		ret = -EINTR;
-	}
-next:
-#endif
-
-	return ret;
-}
-
-/*
- * waking_non_zero_trylock:
- *	1	failed to lock
- *	0	got the lock
- */
-static inline int waking_non_zero_trylock(struct semaphore *sem)
-{
-	int ret;
-#ifndef CONFIG_RMW_INSNS
-	unsigned long flags;
-
-	spin_lock_irqsave(&semaphore_wake_lock, flags);
-	ret = 1;
-	if (atomic_read(&sem->waking) > 0) {
-		atomic_dec(&sem->waking);
-		ret = 0;
-	} else
-		atomic_inc(&sem->count);
-	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
-#else
-	int tmp1, tmp2;
-
-	__asm__ __volatile__
-	  ("1:	movel	%1,%2\n"
-	   "    jle	2f\n"
-	   "	subql	#1,%2\n"
-	   "	casl	%1,%2,%3\n"
-	   "	jne	1b\n"
-	   "	moveq	#0,%0\n"
-	   "2:"
-	   : "=d" (ret), "=d" (tmp1), "=d" (tmp2)
-	   : "m" (sem->waking), "0" (1), "1" (sem->waking));
-	if (ret)
-		atomic_inc(&sem->count);
-#endif
-	return ret;
-}
-
-#endif