#ifndef _H8300_SEMAPHORE_HELPER_H #define _H8300_SEMAPHORE_HELPER_H /* * SMP- and interrupt-safe semaphores helper functions. * * (C) Copyright 1996 Linus Torvalds * * based on * m68k version by Andreas Schwab */ #include <linux/config.h> #include <linux/errno.h> /* * These two _must_ execute atomically wrt each other. */ static inline void wake_one_more(struct semaphore * sem) { atomic_inc((atomic_t *)&sem->sleepers); } static inline int waking_non_zero(struct semaphore *sem) { int ret; unsigned long flags; spin_lock_irqsave(&semaphore_wake_lock, flags); ret = 0; if (sem->sleepers > 0) { sem->sleepers--; ret = 1; } spin_unlock_irqrestore(&semaphore_wake_lock, flags); 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; unsigned long flags; spin_lock_irqsave(&semaphore_wake_lock, flags); ret = 0; if (sem->sleepers > 0) { sem->sleepers--; ret = 1; } else if (signal_pending(tsk)) { atomic_inc(&sem->count); ret = -EINTR; } spin_unlock_irqrestore(&semaphore_wake_lock, flags); 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; unsigned long flags; spin_lock_irqsave(&semaphore_wake_lock, flags); ret = 1; if (sem->sleepers <= 0) atomic_inc(&sem->count); else { sem->sleepers--; ret = 0; } spin_unlock_irqrestore(&semaphore_wake_lock, flags); return ret; } #endif