/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */ #ifndef __ASM_CRIS_ATOMIC__ #define __ASM_CRIS_ATOMIC__ #include #include #include /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc.. */ typedef struct { volatile int counter; } atomic_t; #define ATOMIC_INIT(i) { (i) } #define atomic_read(v) ((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) /* These should be written in asm but we do it in C for now. */ static inline void atomic_add(int i, volatile atomic_t *v) { unsigned long flags; cris_atomic_save(v, flags); v->counter += i; cris_atomic_restore(v, flags); } static inline void atomic_sub(int i, volatile atomic_t *v) { unsigned long flags; cris_atomic_save(v, flags); v->counter -= i; cris_atomic_restore(v, flags); } static inline int atomic_add_return(int i, volatile atomic_t *v) { unsigned long flags; int retval; cris_atomic_save(v, flags); retval = (v->counter += i); cris_atomic_restore(v, flags); return retval; } #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) static inline int atomic_sub_return(int i, volatile atomic_t *v) { unsigned long flags; int retval; cris_atomic_save(v, flags); retval = (v->counter -= i); cris_atomic_restore(v, flags); return retval; } static inline int atomic_sub_and_test(int i, volatile atomic_t *v) { int retval; unsigned long flags; cris_atomic_save(v, flags); retval = (v->counter -= i) == 0; cris_atomic_restore(v, flags); return retval; } static inline void atomic_inc(volatile atomic_t *v) { unsigned long flags; cris_atomic_save(v, flags); (v->counter)++; cris_atomic_restore(v, flags); } static inline void atomic_dec(volatile atomic_t *v) { unsigned long flags; cris_atomic_save(v, flags); (v->counter)--; cris_atomic_restore(v, flags); } static inline int atomic_inc_return(volatile atomic_t *v) { unsigned long flags; int retval; cris_atomic_save(v, flags); retval = ++(v->counter); cris_atomic_restore(v, flags); return retval; } static inline int atomic_dec_return(volatile atomic_t *v) { unsigned long flags; int retval; cris_atomic_save(v, flags); retval = --(v->counter); cris_atomic_restore(v, flags); return retval; } static inline int atomic_dec_and_test(volatile atomic_t *v) { int retval; unsigned long flags; cris_atomic_save(v, flags); retval = --(v->counter) == 0; cris_atomic_restore(v, flags); return retval; } static inline int atomic_inc_and_test(volatile atomic_t *v) { int retval; unsigned long flags; cris_atomic_save(v, flags); retval = ++(v->counter) == 0; cris_atomic_restore(v, flags); return retval; } static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { int ret; unsigned long flags; cris_atomic_save(v, flags); ret = v->counter; if (likely(ret == old)) v->counter = new; cris_atomic_restore(v, 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; cris_atomic_save(v, flags); ret = v->counter; if (ret != u) v->counter += a; cris_atomic_restore(v, flags); return ret != u; } #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) /* Atomic operations are already serializing */ #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 #endif