1 #ifndef __ASM_SH_ATOMIC_H 2 #define __ASM_SH_ATOMIC_H 3 4 /* 5 * Atomic operations that C can't guarantee us. Useful for 6 * resource counting etc.. 7 * 8 */ 9 10 #include <linux/compiler.h> 11 #include <linux/types.h> 12 #include <asm/system.h> 13 14 #define ATOMIC_INIT(i) ( (atomic_t) { (i) } ) 15 16 #define atomic_read(v) ((v)->counter) 17 #define atomic_set(v,i) ((v)->counter = (i)) 18 19 #if defined(CONFIG_GUSA_RB) 20 #include <asm/atomic-grb.h> 21 #elif defined(CONFIG_CPU_SH4A) 22 #include <asm/atomic-llsc.h> 23 #else 24 #include <asm/atomic-irq.h> 25 #endif 26 27 #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) 28 29 #define atomic_dec_return(v) atomic_sub_return(1,(v)) 30 #define atomic_inc_return(v) atomic_add_return(1,(v)) 31 32 /* 33 * atomic_inc_and_test - increment and test 34 * @v: pointer of type atomic_t 35 * 36 * Atomically increments @v by 1 37 * and returns true if the result is zero, or false for all 38 * other cases. 39 */ 40 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 41 42 #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) 43 #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) 44 45 #define atomic_inc(v) atomic_add(1,(v)) 46 #define atomic_dec(v) atomic_sub(1,(v)) 47 48 #ifndef CONFIG_GUSA_RB 49 static inline int atomic_cmpxchg(atomic_t *v, int old, int new) 50 { 51 int ret; 52 unsigned long flags; 53 54 local_irq_save(flags); 55 ret = v->counter; 56 if (likely(ret == old)) 57 v->counter = new; 58 local_irq_restore(flags); 59 60 return ret; 61 } 62 63 static inline int atomic_add_unless(atomic_t *v, int a, int u) 64 { 65 int ret; 66 unsigned long flags; 67 68 local_irq_save(flags); 69 ret = v->counter; 70 if (ret != u) 71 v->counter += a; 72 local_irq_restore(flags); 73 74 return ret != u; 75 } 76 #endif 77 78 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 79 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) 80 81 /* Atomic operations are already serializing on SH */ 82 #define smp_mb__before_atomic_dec() barrier() 83 #define smp_mb__after_atomic_dec() barrier() 84 #define smp_mb__before_atomic_inc() barrier() 85 #define smp_mb__after_atomic_inc() barrier() 86 87 #include <asm-generic/atomic.h> 88 #endif /* __ASM_SH_ATOMIC_H */ 89