kolibrios-fun/drivers/include/linux/spinlock_up.h
Sergey Semyonov (Serge) e3f61693b7 ddk: update
git-svn-id: svn://kolibrios.org@4065 a494cfbc-eb01-0410-851d-a64ba20cac60
2013-10-20 23:07:47 +00:00

80 lines
2.4 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. However, we still need
* the compiler barriers, because we do not want the compiler to
* move potentially faulting instructions (notably user accesses)
* into the locked sequence, resulting in non-atomic execution.
*/
#ifdef CONFIG_DEBUG_SPINLOCK
#define __raw_spin_is_locked(x) ((x)->slock == 0)
static inline void __raw_spin_lock(raw_spinlock_t *lock)
{
lock->slock = 0;
}
static inline void
__raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags)
{
local_irq_save(flags);
lock->slock = 0;
}
static inline int __raw_spin_trylock(raw_spinlock_t *lock)
{
char oldval = lock->slock;
lock->slock = 0;
return oldval > 0;
}
static inline void __raw_spin_unlock(raw_spinlock_t *lock)
{
lock->slock = 1;
}
/*
* Read-write spinlocks. No debug version.
*/
#define __raw_read_lock(lock) do { (void)(lock); } while (0)
#define __raw_write_lock(lock) do { (void)(lock); } while (0)
#define __raw_read_trylock(lock) ({ (void)(lock); 1; })
#define __raw_write_trylock(lock) ({ (void)(lock); 1; })
#define __raw_read_unlock(lock) do { (void)(lock); } while (0)
#define __raw_write_unlock(lock) do { (void)(lock); } while (0)
#else /* DEBUG_SPINLOCK */
#define __raw_spin_is_locked(lock) ((void)(lock), 0)
/* for sched.c and kernel_lock.c: */
# define __raw_spin_lock(lock) do { (void)(lock); } while (0)
# define __raw_spin_lock_flags(lock, flags) do { (void)(lock); } while (0)
# define __raw_spin_unlock(lock) do { (void)(lock); } while (0)
# define __raw_spin_trylock(lock) ({ (void)(lock); 1; })
#endif /* DEBUG_SPINLOCK */
#define __raw_spin_is_contended(lock) (((void)(lock), 0))
#define __raw_read_can_lock(lock) (((void)(lock), 1))
#define __raw_write_can_lock(lock) (((void)(lock), 1))
#define __raw_spin_unlock_wait(lock) \
do { cpu_relax(); } while (__raw_spin_is_locked(lock))
#endif /* __LINUX_SPINLOCK_UP_H */