/* * include/asm-v850/atomic.h -- Atomic operations * * Copyright (C) 2001,02 NEC Corporation * Copyright (C) 2001,02 Miles Bader <miles@gnu.org> * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of this * archive for more details. * * Written by Miles Bader <miles@gnu.org> */ #ifndef __V850_ATOMIC_H__ #define __V850_ATOMIC_H__ #include <asm/system.h> #ifdef CONFIG_SMP #error SMP not supported #endif typedef struct { int counter; } atomic_t; #define ATOMIC_INIT(i) { (i) } #ifdef __KERNEL__ #define atomic_read(v) ((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) static inline int atomic_add_return (int i, volatile atomic_t *v) { unsigned long flags; int res; local_irq_save (flags); res = v->counter + i; v->counter = res; local_irq_restore (flags); return res; } static __inline__ int atomic_sub_return (int i, volatile atomic_t *v) { unsigned long flags; int res; local_irq_save (flags); res = v->counter - i; v->counter = res; local_irq_restore (flags); return res; } static __inline__ void atomic_clear_mask (unsigned long mask, unsigned long *addr) { unsigned long flags; local_irq_save (flags); *addr &= ~mask; local_irq_restore (flags); } #endif #define atomic_add(i, v) atomic_add_return ((i), (v)) #define atomic_sub(i, v) atomic_sub_return ((i), (v)) #define atomic_dec_return(v) atomic_sub_return (1, (v)) #define atomic_inc_return(v) atomic_add_return (1, (v)) #define atomic_inc(v) atomic_inc_return (v) #define atomic_dec(v) atomic_dec_return (v) /* * atomic_inc_and_test - increment and test * @v: pointer of type atomic_t * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all * other cases. */ #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) #define atomic_sub_and_test(i,v) (atomic_sub_return ((i), (v)) == 0) #define atomic_dec_and_test(v) (atomic_sub_return (1, (v)) == 0) #define atomic_add_negative(i,v) (atomic_add_return ((i), (v)) < 0) static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { int ret; unsigned long flags; local_irq_save(flags); ret = v->counter; if (likely(ret == old)) v->counter = new; local_irq_restore(flags); return ret; } #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) static inline int atomic_add_unless(atomic_t *v, int a, int u) { int ret; unsigned long flags; local_irq_save(flags); ret = v->counter; if (ret != u) v->counter += a; local_irq_restore(flags); return ret != u; } #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) /* Atomic operations are already serializing on ARM */ #define smp_mb__before_atomic_dec() barrier() #define smp_mb__after_atomic_dec() barrier() #define smp_mb__before_atomic_inc() barrier() #define smp_mb__after_atomic_inc() barrier() #include <asm-generic/atomic.h> #endif /* __V850_ATOMIC_H__ */