[linux.git] / include / asm-m68k / semaphore-helper.h

#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
Commit	Line	Data
1da177e4 LT	1	#ifndef _M68K_SEMAPHORE_HELPER_H
	2	#define _M68K_SEMAPHORE_HELPER_H
	3
	4	/*
	5	* SMP- and interrupt-safe semaphores helper functions.
	6	*
	7	* (C) Copyright 1996 Linus Torvalds
	8	*
	9	* m68k version by Andreas Schwab
	10	*/
	11
1da177e4 LT	12	#include <linux/errno.h>
	13
	14	/*
	15	* These two _must_ execute atomically wrt each other.
	16	*/
	17	static inline void wake_one_more(struct semaphore * sem)
	18	{
	19	atomic_inc(&sem->waking);
	20	}
	21
	22	#ifndef CONFIG_RMW_INSNS
	23	extern spinlock_t semaphore_wake_lock;
	24	#endif
	25
	26	static inline int waking_non_zero(struct semaphore *sem)
	27	{
	28	int ret;
	29	#ifndef CONFIG_RMW_INSNS
	30	unsigned long flags;
	31
	32	spin_lock_irqsave(&semaphore_wake_lock, flags);
	33	ret = 0;
	34	if (atomic_read(&sem->waking) > 0) {
	35	atomic_dec(&sem->waking);
	36	ret = 1;
	37	}
	38	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
	39	#else
	40	int tmp1, tmp2;
	41
	42	__asm__ __volatile__
	43	("1: movel %1,%2\n"
	44	" jle 2f\n"
	45	" subql #1,%2\n"
	46	" casl %1,%2,%3\n"
	47	" jne 1b\n"
	48	" moveq #1,%0\n"
	49	"2:"
	50	: "=d" (ret), "=d" (tmp1), "=d" (tmp2)
	51	: "m" (sem->waking), "0" (0), "1" (sem->waking));
	52	#endif
	53
	54	return ret;
	55	}
	56
	57	/*
	58	* waking_non_zero_interruptible:
	59	* 1 got the lock
	60	* 0 go to sleep
	61	* -EINTR interrupted
	62	*/
	63	static inline int waking_non_zero_interruptible(struct semaphore *sem,
	64	struct task_struct *tsk)
	65	{
	66	int ret;
	67	#ifndef CONFIG_RMW_INSNS
	68	unsigned long flags;
	69
	70	spin_lock_irqsave(&semaphore_wake_lock, flags);
	71	ret = 0;
	72	if (atomic_read(&sem->waking) > 0) {
	73	atomic_dec(&sem->waking);
	74	ret = 1;
	75	} else if (signal_pending(tsk)) {
76	atomic_inc(&sem->count);
77	ret = -EINTR;
78	}
79	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
80	#else
81	int tmp1, tmp2;
82
83	__asm__ __volatile__
84	("1: movel %1,%2\n"
85	" jle 2f\n"
86	" subql #1,%2\n"
87	" casl %1,%2,%3\n"
88	" jne 1b\n"
89	" moveq #1,%0\n"
90	" jra %a4\n"
91	"2:"
92	: "=d" (ret), "=d" (tmp1), "=d" (tmp2)
93	: "m" (sem->waking), "i" (&&next), "0" (0), "1" (sem->waking));
94	if (signal_pending(tsk)) {
95	atomic_inc(&sem->count);
96	ret = -EINTR;
97	}
98	next:
99	#endif
100
101	return ret;
102	}
103
104	/*
105	* waking_non_zero_trylock:
106	* 1 failed to lock
107	* 0 got the lock
108	*/
109	static inline int waking_non_zero_trylock(struct semaphore *sem)
110	{
111	int ret;
112	#ifndef CONFIG_RMW_INSNS
113	unsigned long flags;
114
115	spin_lock_irqsave(&semaphore_wake_lock, flags);
116	ret = 1;
117	if (atomic_read(&sem->waking) > 0) {
118	atomic_dec(&sem->waking);
119	ret = 0;
120	} else
121	atomic_inc(&sem->count);
122	spin_unlock_irqrestore(&semaphore_wake_lock, flags);
123	#else
124	int tmp1, tmp2;
125
126	__asm__ __volatile__
127	("1: movel %1,%2\n"
128	" jle 2f\n"
129	" subql #1,%2\n"
130	" casl %1,%2,%3\n"
131	" jne 1b\n"
132	" moveq #0,%0\n"
133	"2:"
134	: "=d" (ret), "=d" (tmp1), "=d" (tmp2)
135	: "m" (sem->waking), "0" (1), "1" (sem->waking));
136	if (ret)
137	atomic_inc(&sem->count);
138	#endif
139	return ret;
140	}
141
142	#endif