/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */ #ifndef __ASM_CRIS_ATOMIC__ #define __ASM_CRIS_ATOMIC__ #include <linux/compiler.h> #include <linux/types.h> #include <asm/cmpxchg.h> #include <arch/atomic.h> #include <arch/system.h> #include <asm/barrier.h> /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc.. */ #define ATOMIC_INIT(i) { (i) } #define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) /* These should be written in asm but we do it in C for now. */ #define ATOMIC_OP(op, c_op) \ static inline void atomic_##op(int i, volatile atomic_t *v) \ { \ unsigned long flags; \ cris_atomic_save(v, flags); \ v->counter c_op i; \ cris_atomic_restore(v, flags); \ } \ #define ATOMIC_OP_RETURN(op, c_op) \ static inline int atomic_##op##_return(int i, volatile atomic_t *v) \ { \ unsigned long flags; \ int retval; \ cris_atomic_save(v, flags); \ retval = (v->counter c_op i); \ cris_atomic_restore(v, flags); \ return retval; \ } #define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op) ATOMIC_OPS(add, +=) ATOMIC_OPS(sub, -=) #undef ATOMIC_OPS #undef ATOMIC_OP_RETURN #undef ATOMIC_OP #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) 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; } #endif