77 lines
2.1 KiB
C
77 lines
2.1 KiB
C
#ifndef __LINUX_SPINLOCK_UP_H
|
|
#define __LINUX_SPINLOCK_UP_H
|
|
|
|
#ifndef __LINUX_SPINLOCK_H
|
|
# error "please don't include this file directly"
|
|
#endif
|
|
|
|
/*
|
|
* include/linux/spinlock_up.h - UP-debug version of spinlocks.
|
|
*
|
|
* portions Copyright 2005, Red Hat, Inc., Ingo Molnar
|
|
* Released under the General Public License (GPL).
|
|
*
|
|
* In the debug case, 1 means unlocked, 0 means locked. (the values
|
|
* are inverted, to catch initialization bugs)
|
|
*
|
|
* No atomicity anywhere, we are on UP.
|
|
*/
|
|
|
|
#ifdef CONFIG_DEBUG_SPINLOCK
|
|
#define arch_spin_is_locked(x) ((x)->slock == 0)
|
|
|
|
static inline void arch_spin_lock(arch_spinlock_t *lock)
|
|
{
|
|
lock->slock = 0;
|
|
}
|
|
|
|
static inline void
|
|
arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags)
|
|
{
|
|
local_irq_save(flags);
|
|
lock->slock = 0;
|
|
}
|
|
|
|
static inline int arch_spin_trylock(arch_spinlock_t *lock)
|
|
{
|
|
char oldval = lock->slock;
|
|
|
|
lock->slock = 0;
|
|
|
|
return oldval > 0;
|
|
}
|
|
|
|
static inline void arch_spin_unlock(arch_spinlock_t *lock)
|
|
{
|
|
lock->slock = 1;
|
|
}
|
|
|
|
/*
|
|
* Read-write spinlocks. No debug version.
|
|
*/
|
|
#define arch_read_lock(lock) do { (void)(lock); } while (0)
|
|
#define arch_write_lock(lock) do { (void)(lock); } while (0)
|
|
#define arch_read_trylock(lock) ({ (void)(lock); 1; })
|
|
#define arch_write_trylock(lock) ({ (void)(lock); 1; })
|
|
#define arch_read_unlock(lock) do { (void)(lock); } while (0)
|
|
#define arch_write_unlock(lock) do { (void)(lock); } while (0)
|
|
|
|
#else /* DEBUG_SPINLOCK */
|
|
#define arch_spin_is_locked(lock) ((void)(lock), 0)
|
|
/* for sched.c and kernel_lock.c: */
|
|
# define arch_spin_lock(lock) do { (void)(lock); } while (0)
|
|
# define arch_spin_lock_flags(lock, flags) do { (void)(lock); } while (0)
|
|
# define arch_spin_unlock(lock) do { (void)(lock); } while (0)
|
|
# define arch_spin_trylock(lock) ({ (void)(lock); 1; })
|
|
#endif /* DEBUG_SPINLOCK */
|
|
|
|
#define arch_spin_is_contended(lock) (((void)(lock), 0))
|
|
|
|
#define arch_read_can_lock(lock) (((void)(lock), 1))
|
|
#define arch_write_can_lock(lock) (((void)(lock), 1))
|
|
|
|
#define arch_spin_unlock_wait(lock) \
|
|
do { cpu_relax(); } while (arch_spin_is_locked(lock))
|
|
|
|
#endif /* __LINUX_SPINLOCK_UP_H */
|