#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 __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_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 */