mirror of
https://github.com/adulau/aha.git
synced 2024-12-29 04:06:22 +00:00
62c4f0a2d5
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
142 lines
2.7 KiB
C
142 lines
2.7 KiB
C
#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
|