1 #ifndef __ASM_SH_ATOMIC_H 2 #define __ASM_SH_ATOMIC_H 3 4 #if defined(CONFIG_CPU_J2) 5 6 #include <asm-generic/atomic.h> 7 8 #else 9 10 /* 11 * Atomic operations that C can't guarantee us. Useful for 12 * resource counting etc.. 13 * 14 */ 15 16 #include <linux/compiler.h> 17 #include <linux/types.h> 18 #include <asm/cmpxchg.h> 19 #include <asm/barrier.h> 20 21 #define ATOMIC_INIT(i) { (i) } 22 23 #define atomic_read(v) READ_ONCE((v)->counter) 24 #define atomic_set(v,i) WRITE_ONCE((v)->counter, (i)) 25 26 #if defined(CONFIG_GUSA_RB) 27 #include <asm/atomic-grb.h> 28 #elif defined(CONFIG_CPU_SH4A) 29 #include <asm/atomic-llsc.h> 30 #else 31 #include <asm/atomic-irq.h> 32 #endif 33 34 #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) 35 #define atomic_dec_return(v) atomic_sub_return(1, (v)) 36 #define atomic_inc_return(v) atomic_add_return(1, (v)) 37 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 38 #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) 39 #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) 40 41 #define atomic_inc(v) atomic_add(1, (v)) 42 #define atomic_dec(v) atomic_sub(1, (v)) 43 44 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 45 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 46 47 /** 48 * __atomic_add_unless - add unless the number is a given value 49 * @v: pointer of type atomic_t 50 * @a: the amount to add to v... 51 * @u: ...unless v is equal to u. 52 * 53 * Atomically adds @a to @v, so long as it was not @u. 54 * Returns the old value of @v. 55 */ 56 static inline int __atomic_add_unless(atomic_t *v, int a, int u) 57 { 58 int c, old; 59 c = atomic_read(v); 60 for (;;) { 61 if (unlikely(c == (u))) 62 break; 63 old = atomic_cmpxchg((v), c, c + (a)); 64 if (likely(old == c)) 65 break; 66 c = old; 67 } 68 69 return c; 70 } 71 72 #endif /* CONFIG_CPU_J2 */ 73 74 #endif /* __ASM_SH_ATOMIC_H */ 75